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The PDF version of the Atlas of Genetics and Cytogenetics in Oncology and Haematology is a reissue of the original articles published in collaboration with the Institute for Scientific and Technical Information (INstitut de l’Information Scientifique et Technique - INIST) of the French National Center for Scientific Research (CNRS) on its electronic publishing platform I-Revues. Online and PDF versions of the Atlas of Genetics and Cytogenetics in Oncology and Haematology are hosted by INIST-CNRS.


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Atlas Genet Cytogenet Oncol Haematol. 2015; 19(4)


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Editorial Board Sreeparna Banerjee (Ankara, Turkey) Solid Tumours Section Alessandro Beghini (Milan, Italy) Genes Section Anne von Bergh (Rotterdam, The Netherlands) Genes / Leukaemia Sections Judith Bovée (Leiden, The Netherlands) Solid Tumours Section Vasantha Brito-Babapulle (London, UK) Leukaemia Section Charles Buys (Groningen, The Netherlands) Deep Insights Section Antonio Cuneo (Ferrara, Italy) Leukaemia Section Paola Dal Cin (Boston, Massachussetts) Genes / Solid Tumours Section Brigitte Debuire (Villejuif, France) Deep Insights Section Marc De Braekeleer (Brest, France) Genes / Leukaemia Sections François Desangles (Paris, France) Leukaemia / Solid Tumours Sections Enric Domingo-Villanueva (London, UK) Solid Tumours Section Ayse Erson (Ankara, Turkey) Solid Tumours Section Richard Gatti (Los Angeles, California) Cancer-Prone Diseases / Deep Insights Sections Ad Geurts van Kessel (Nijmegen, The Netherlands) Cancer-Prone Diseases Section Oskar Haas (Vienna, Austria) Genes / Leukaemia Sections Anne Hagemeijer (Leuven, Belgium) Deep Insights Section Nyla Heerema (Colombus, Ohio) Leukaemia Section Jim Heighway (Liverpool, UK) Genes / Deep Insights Sections Sakari Knuutila (Helsinki, Finland) Deep Insights Section Lidia Larizza (Milano, Italy) Solid Tumours Section Lisa Lee-Jones (Newcastle, UK) Solid Tumours Section Edmond Ma (Hong Kong, China) Leukaemia Section Roderick McLeod (Braunschweig, Germany) Deep Insights / Education Sections Cristina Mecucci (Perugia, Italy) Genes / Leukaemia Sections Fredrik Mertens (Lund, Sweden) Solid Tumours Section Konstantin Miller (Hannover, Germany) Education Section Felix Mitelman (Lund, Sweden) Deep Insights Section Hossain Mossafa (Cergy Pontoise, France) Leukaemia Section Stefan Nagel (Braunschweig, Germany) Deep Insights / Education Sections Florence Pedeutour (Nice, France) Genes / Solid Tumours Sections Elizabeth Petty (Ann Harbor, Michigan) Deep Insights Section Susana Raimondi (Memphis, Tennesse) Genes / Leukaemia Section Mariano Rocchi (Bari, Italy) Genes Section Alain Sarasin (Villejuif, France) Cancer-Prone Diseases Section Albert Schinzel (Schwerzenbach, Switzerland) Education Section Clelia Storlazzi (Bari, Italy) Genes Section Sabine Strehl (Vienna, Austria) Genes / Leukaemia Sections Nancy Uhrhammer (Clermont Ferrand, France) Genes / Cancer-Prone Diseases Sections Dan Van Dyke (Rochester, Minnesota) Education Section Roberta Vanni (Montserrato, Italy) Solid Tumours Section Franck Viguié (Paris, France) Leukaemia Section José Luis Vizmanos (Pamplona, Spain) Leukaemia Section Thomas Wan (Hong Kong, China) Genes / Leukaemia Sections Adriana Zamecnikova (Kuwait) Leukaemia Section



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Table of contents

Gene Section

RNASET2 (ribonuclease T2) 240 Francesco Acquati

ATMIN (ATM interactor) 245 Jörg Heierhorst

CEBPA (CCAAT/enhancer binding protein (C/EBP), alpha) 249 Tian V Tian, Thomas Graf

EEF1A1 (eukaryotic translation elongation factor 1 alpha 1) 256 Bruna Scaggiante, Alessandra Bosutti

HOXC8 (homeobox C8) 266 Shuang Huang, Yong Li

MIR200C (microRNA 200c) 270 Merve Mutlu, Özge Saatçi, Umar Raza, Erol Eyüpoglu, Emre Yurdusev, Özgür Sahin

PDSS2 (prenyl (decaprenyl) diphosphate synthase, subunit 2) 286 Ping Chen, Qi Chen

PYCARD (PYD and CARD domain containing) 291 Jeffrey H Dunn, Mayumi Fujita

TRIM27 (tripartite motif containing 27) 302 Georgia Zoumpoulidou, Sibylle Mittnacht

Leukaemia Section

t(10;11)(p12;q23) KMT2A/NEBL 308 Claus Meyer, Mariana Emerenciano, Maria S Pombo-de-Oliveira, Rolf Marschalek

Solid Tumour Section

Lung: Translocations in Adenocarcinoma 311 Jean-Loup Huret



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RNASET2 (ribonuclease T2) Francesco Acquati

Dept of Theoretical and Applied Sciences, University of Insubria - Varese, Italy (FA)

Published in Atlas Database: June 2014

Online updated version : http://AtlasGeneticsOncology.org/Genes/RNASET2ID518ch6q27.html DOI: 10.4267/2042/56433

This article is an update of : Acquati F, Campomenosi P. RNASET2 (ribonuclease T2). Atlas Genet Cytogenet Oncol Haematol 2007;11(3):219-221. This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 2.0 France Licence. © 2015 Atlas of Genetics and Cytogenetics in Oncology and Haematology

Abstract Review on RNASET2, with data on DNA/RNA, on the protein encoded and where the gene is implicated.

Identity Other names: RNASE6PL, RP11-514O12.3, bA514O12.3

HGNC (Hugo): RNASET2

Location: 6q27

Local order: Telomeric to RPS6KA2, centromeric to FGFR1OP.

Note: This gene represents the first human member of the Rh/T2/S-glycoprotein family of extracellular ribonucleases. It belongs to the recently defined class of tumor-antagonizing genes, based on its ability to suppress tumor growth in vivo, but not in vitro. It is likely involved in the pathogenesis of several human neoplasias (both solid and haematological) such as ovarian cancer, melanoma and non-Hodgkin lymphoma. Mutations in this gene have also been recently described in children affected by a rare congenital neurological defect. Moreover, GWAS studies have recently reported the association of gene variants mapping close to the RNASET2 gene with susceptibilty to a few autoimmune disorders.

RNASET2 (ribonuclease T2) Acquati F


I-IX: RNASET2 exons; Red boxes: CAS I and CAS II catalytic sites; Dark green boxes: untranslated regions.

DNA/RNA Description The RNASET2 gene has been mapped in the peritelomeric region of the long arm of human chromosome 6 (6q27), which has been consistently reported to be rearreanged in several human neoplasias. It's coding region is split in 9 exons, spanning approximatly 27 kb of genomic DNA. The translation initiation codon is located in exon 1 and the stop codon in exon 9. Exons III and VI encode the two CAS motifs (Catalytic Active Sites) responsible for the ribonuclease activity of the RNASET2 protein. However, the catalytic activity of the RNASET2 protein is apparently not required for some biological functions, as described for other members of the T2-Rh-S RNase gene family.

Transcription The RNASET2 gene is transcribed in the telomere-to-centromere orientation to produce an ubiquitously expressed mRNA approximately 1,4 kb in length. EST clones representing splice variants of the same gene have been described. Transcription of this gene is rather ubiquitous, with highest expression levels being reported in spleen, pancreas and leukocytes.

Pseudogene A processed pseudogene showing 85% identity with RNASET2 mRNA maps to chromosome

7p11.2. The expression pattern of this pseudogene is not known.

Protein Description The aminoacid sequence of RNASET2 depicts a typical member of the highly conserved Rh7T2/S family of extracellular, acid ribonucleases. The X-ray structure of the protein was recently reported, showing the occurrence of the α+β core fold typically observed in other members of the Rh/T2/S protein family. The catalytic activity of the protein was shown to be significantly inhibited by zinc and copper ions.

Expression In normal human tissues, the RNASET2 protein has been detected in pancreas, stomach, small intestine, colon, salivary glands, liver, thyroid, adrenal glands, lymphoid organs, lungs, melanocytes, ovarian surface and Fallopian tube epithelium. Expression of the RNASET2 protein has also been detected in several human ovarian cancer cell lines and in some melanoma, prostate, pancreatic and breast carcinoma cell lines.

Localisation The full-length RNASET2 protein contains 256 aminoacids and displays an apparent MW of 36 kDa in its secreted form. Two 31 and 27 kDa C-terminal proteolytic products have also been observed intracellularly in several human cancer cell lines.

The RNASET2 protein contains 256 aminoacids. Gold box: signal peptide for secretion (residues 1-24); Gray box: catalytic fold; Red boxes: Conserved Active Sites (CAS I-II); Yellow boxes: putative N-glycosilation sites.



The extracellular RNASET2 protein is detected in cell culture supernatants as the full lenght 36 kDa forms. The intracellular localization pattern of the RNASET2 protein suggests a localization in the secretory compartments (endoplasmic reticulum and Golgi apparatus) but also in lysosomes and processing bodies (P-bodies).

Function Biochemical function: RNASET2 is an acid ribonuclease with optimal activity at pH 5 and preferential cleavage of poly-A and poly-U homo-polyribonucleotides. Biological function: RNASET2 behaves as a tumor antagonizing gene in ovarian cancer models, since experimental manipulation of this gene's expression levels in human ovarian cancer cell lines is associated with a significant change in their tumorigenic and metastasizing potential in vivo. The oncosuppressive role of this protein in ovarian cancer models is associated with a marked recruitment of cells form the monocyte/macrophage lineage within the tumor mass. In an experimental model of colorectal cancer, recombinant RNASET2 was also found to display a marked oncosuppressive activity. Strikingly, in both models the ribonuclease catalytic activity was apparently dispensable for RNASET2 to play such antioncogenic role. A role for in vivo tumor suppression for RNASET2 has also been established in a model of malignant melanoma. Moreover, the human RNASET2 gene has been recently implicated in sperm motility and stress-induced apoptosis in melanocytes. Recent investigations carried out on RNASET2 orthologs have suggested several additional biological roles for this gene family, such as in vivo priming of dendritic cells for Th2-helper response, inhibition of angiogenesis in vivo, ribosomal RNA decay in plants and CNS physiology.

Homology The primary sequenze of RNASET2 shows strong homology to the Rh/T2/S family of secreted ribonucleases.

Mutations Note Epigenetics: The RNASET2 gene has been reported to be frequently down-regulated in several human ovarian cancer cell lines and primary tumors. The underlying molecular mechanism is currently unknown.

Germinal A common exon-9 missense C708T germline mutation has been described but no evidence for an

association of this allele with human cancer was found. A missense mutation (550T>C ; C184R) and a 2,5 kb deletion spanning exon 2 were found to segregate in families affected with cystic leukoencephalopathy.

Somatic A few common polymorphisms in exons 1, 8 and 9 have been described. In general, coding mutations are rarely found in tumor samples.

Implicated in Ovarian cancer Note Loss of expression or downregulation of RNASET2 occurs in a significant fraction of human ovarian cancer cell lines and primary ovarian tumours. Moreover, the genomic region (chromosome 6q27) where the RNASET2 genes maps has been reported to be frequently deleted or otherwise rearranged in a high fraction of ovarian cancer samples. However, no mutation in the RNASET2 gene have been described so far in human ovarian cancer samples. Therefore, this gene seems to be involved in tumor suppression mainly by means of its downregulation at the transcript/protein level in this cancer type. When overexpressed by gene transfer experiments in human ovarian cancer cell lines displaying a low level of endogenous mRNA, RNASET2 strongly suppresses the tumorigenic and metastatic potential of these cell lines in a murine xenogratf model in vivo. The same observation was reported following a complementary experiment, i.e. by knocking-down RNASET2 expression in a poorly aggressive ovarian cancer cell line expressing high levels of endogenous RNASET2. In both in vivo models, RNASET2-mediated tumor suppression was associated with a marked recruitment of cells from the monocyte/macrophage lineage in the tumor mass. Further experiments have demonstrated a direct chemotactic role for cells from the monocyte/macrophage carried out by the RNASET2 protein. Very recently, downregulation of RNASET2 expression has been associated with resistance to cis-platin and carboplatin in ovarian cancer cells and tissues.

Malignant melanoma Note Besides ovarian carcinoma, the chromosome region 6q27 (where the RNASET2 genes maps) has been reported to be frequently deleted or rearranged in malignant melanoma. Downregulation of RNASET2 has also been reported in cell lines representing this cancer type. Overexpression of RNASET2 in the human melanoma-derived SK-



MEL28 cell line was associated with a significant suppression of tumor growth in vivo (in a xenograft model with immunocompromised mice), but not in vitro, supporting the notion of RNASET2 as a tumor-antagonizing gene whose oncosuppressive action is carried out asimmetrically, i.e. only in the context of a complex tissue architecture where a significant cross-talk between cancer cells and the stromal compartment take place. Moreover, the T2 RNase protein encoded from the Aspergillus niger ortholog gene has been shown to inhibit human melanoma cell growth and metastasis in a xenograft model. The underlying oncosuppressive mechanism in this model was the inhibition of tumor angiogenesis by means of competitive inhibition with angiogenin.

Colorectal cancer Note In an HT29 human colon cancer-derived xenograft experimental model, human recombinant RNASET2 was shown to greatly suppress tumor growth in vivo independent from its catalytic activity. Tumor angiogenesis was mainly affected by recombinant RNASET2 injection in this cancer model.

Anaplastic large cell lymphoma Note More recently, screening of a protein microarray with sera from anaplastic large cell lymphoma (ALCL) patients identified RNASET2 as an ALK-negative ALCL-associated antigen.

Cystic leukoencephalopathy Disease Several loss-of function mutations have been reported in probands affected by cystic leukoencephalopathy, an autosomal recessive disorder whose clinical and radiological phenotype is indistinguishable with respect to the pattern of brain abnormalities observed in people suffering from congenital cytomegalovirus infection. Affected people develop several neurologic abnormalities in the early post-natal period, including psychomotor defects, seizures and sensorineural hearing impairment, characterized by a diagnostic MRI pattern.

Cytogenetics Six independent mutations in the RNASET2 gene have been reported in both familial and sporadic cases affected by cystic leukoencephalopathy. All mutations are predicted to result in a loss of function phenotype.

Abnormal protein The C184R mutant RNASET2 protein expressed from the 550T>C allele showed defective intracellular trafficking, likely due to impaired protein folding or stability.

Autoimmune disorders Disease Genome-wide association studies have recently implicated the RNASET2 locus in the susceptibility for a few autoimmune disorder, such as vitiligo, Crohns' disease and Graves' disease.

References Trubia M, Sessa L, Taramelli R. Mammalian Rh/T2/S-glycoprotein ribonuclease family genes: cloning of a human member located in a region of chromosome 6 (6q27) frequently deleted in human malignancies. Genomics. 1997 Jun 1;42(2):342-4

Acquati F, Morelli C, Cinquetti R, Bianchi MG, Porrini D, Varesco L, Gismondi V, Rocchetti R, Talevi S, Possati L, Magnanini C, Tibiletti MG, Bernasconi B, Daidone MG, Shridhar V, Smith DI, Negrini M, Barbanti-Brodano G, Taramelli R. Cloning and characterization of a senescence inducing and class II tumor suppressor gene in ovarian carcinoma at chromosome region 6q27. Oncogene. 2001a Feb 22;20(8):980-8

Acquati F, Nucci C, Bianchi MG, Gorletta T, Taramelli R. Molecular cloning, tissue distribution, and chromosomal localization of the human homolog of the R2/Th/Stylar ribonuclease gene family. Methods Mol Biol. 2001b;160:87-101

Acquati F, Possati L, Ferrante L, Campomenosi P, Talevi S, Bardelli S, Margiotta C, Russo A, Bortoletto E, Rocchetti R, Calza R, Cinquetti R, Monti L, Salis S, Barbanti-Brodano G, Taramelli R. Tumor and metastasis suppression by the human RNASET2 gene. Int J Oncol. 2005 May;26(5):1159-68

Campomenosi P, Salis S, Lindqvist C, Mariani D, Nordström T, Acquati F, Taramelli R. Characterization of RNASET2, the first human member of the Rh/T2/S family of glycoproteins. Arch Biochem Biophys. 2006 May 15;449(1-2):17-26

Monti L, Rodolfo M, Lo Russo G, Noonan D, Acquati F, Taramelli R. RNASET2 as a tumor antagonizing gene in a melanoma cancer model. Oncol Res. 2008;17(2):69-74

Henneke M, Diekmann S, Ohlenbusch A, Kaiser J, Engelbrecht V, Kohlschütter A, Krätzner R, Madruga-Garrido M, Mayer M, Opitz L, Rodriguez D, Rüschendorf F, Schumacher J, Thiele H, Thoms S, Steinfeld R, Nürnberg P, Gärtner J. RNASET2-deficient cystic leukoencephalopathy resembles congenital cytomegalovirus brain infection. Nat Genet. 2009 Jul;41(7):773-5

Quan C, Ren YQ, Xiang LH, Sun LD, Xu AE, Gao XH, Chen HD, Pu XM, Wu RN, Liang CZ, Li JB, Gao TW, Zhang JZ, Wang XL, Wang J, Yang RY, Liang L, Yu JB, Zuo XB, Zhang SQ, Zhang SM, Chen G, Zheng XD, Li P, Zhu J, Li YW, Wei XD, Hong WS, Ye Y, Zhang Y, Wu WS, Cheng H, Dong PL, Hu DY, Li Y, Li M, Zhang X, Tang HY, Tang XF, Xu SX, He SM, Lv YM, Shen M, Jiang HQ, Wang Y, Li K, Kang XJ, Liu YQ, Sun L, Liu ZF, Xie SQ, Zhu CY, Xu Q, Gao JP, Hu WL, Ni C, Pan TM, Li Y, Yao S, He CF, Liu YS, Yu ZY, Yin XY, Zhang FY, Yang S, Zhou Y, Zhang XJ. Genome-wide association study for vitiligo identifies susceptibility loci at 6q27 and the MHC. Nat Genet. 2010 Jul;42(7):614-8

Acquati F, Bertilaccio S, Grimaldi A, Monti L, Cinquetti R, Bonetti P, Lualdi M, Vidalino L, Fabbri M, Sacco MG, van Rooijen N, Campomenosi P, Vigetti D, Passi A, Riva C, Capella C, Sanvito F, Doglioni C, Gribaldo L, Macchi P,



Sica A, Noonan DM, Ghia P, Taramelli R. Microenvironmental control of malignancy exerted by RNASET2, a widely conserved extracellular RNase. Proc Natl Acad Sci U S A. 2011 Jan 18;108(3):1104-9

Haud N, Kara F, Diekmann S, Henneke M, Willer JR, Hillwig MS, Gregg RG, Macintosh GC, Gärtner J, Alia A, Hurlstone AF. rnaset2 mutant zebrafish model familial cystic leukoencephalopathy and reveal a role for RNase T2 in degrading ribosomal RNA. Proc Natl Acad Sci U S A. 2011 Jan 18;108(3):1099-103

Chu X, Pan CM, Zhao SX, Liang J, Gao GQ, Zhang XM, Yuan GY, Li CG, Xue LQ, Shen M, Liu W, Xie F, Yang SY, Wang HF, Shi JY, Sun WW, Du WH, Zuo CL, Shi JX, Liu BL, Guo CC, Zhan M, Gu ZH, Zhang XN, Sun F, Wang ZQ, Song ZY, Zou CY, Sun WH, Guo T, Cao HM, Ma JH, Han B, Li P, Jiang H, Huang QH, Liang L, Liu LB, Chen G, Su Q, Peng YD, Zhao JJ, Ning G, Chen Z, Chen JL, Chen SJ, Huang W, Song HD. A genome-wide association study identifies two new risk loci for Graves' disease. Nat Genet. 2011 Aug 14;43(9):897-901

Patel S, Chen H, Monti L, Gould E, Haralambieva E, Schmid J, Toomey D, Woessmann W, Roncador G, Hatton CS, Liggins AP, Taramelli R, Banham AH, Acquati F, Murphy D, Pulford K. RNASET2--an autoantigen in anaplastic large cell lymphoma identified by protein array

analysis. J Proteomics. 2012 Sep 18;75(17):5279-92

Acquati F, Lualdi M, Bertilaccio S, Monti L, Turconi G, Fabbri M, Grimaldi A, Anselmo A, Inforzato A, Collotta A, Cimetti L, Riva C, Gribaldo L, Ghia P, Taramelli R. Loss of function of Ribonuclease T2, an ancient and phylogenetically conserved RNase, plays a crucial role in ovarian tumorigenesis. Proc Natl Acad Sci U S A. 2013 May 14;110(20):8140-5

Yang SK, Hong M, Zhao W, Jung Y, Baek J, Tayebi N, Kim KM, Ye BD, Kim KJ, Park SH, Lee I, Lee EJ, Kim WH, Cheon JH, Kim YH, Jang BI, Kim HS, Choi JH, Koo JS, Lee JH, Jung SA, Lee YJ, Jang JY, Shin HD, Kang D, Youn HS, Liu J, Song K. Genome-wide association study of Crohn's disease in Koreans revealed three new susceptibility loci and common attributes of genetic susceptibility across ethnic populations. Gut. 2014 Jan;63(1):80-7

Wang Q, Jiang M, Wu J, Ma Y, Li T, Chen Q, Zhang X, Xiang L. Stress-induced RNASET2 overexpression mediates melanocyte apoptosis via the TRAF2 pathway in vitro. Cell Death Dis. 2014 Jan 23;5:e1022

This article should be referenced as such:

Acquati F. RNASET2 (ribonuclease T2). Atlas Genet Cytogenet Oncol Haematol. 2015; 19(4):240-244.

Gene Section Review



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ATMIN (ATM interactor) Jörg Heierhorst

St. Vincent's Institute of Medical Research, and Department of Medicine St Vincent's Hospital, The University of Melbourne, 9 Princes Street, Fitzroy, Victoria 3065, Australia (JH)

Published in Atlas Database: July 2014

Online updated version : http://AtlasGeneticsOncology.org/Genes/ATMINID45745ch16q23.html DOI: 10.4267/2042/56434

This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 2.0 France Licence. © 2015 Atlas of Genetics and Cytogenetics in Oncology and Haematology

Abstract Review on ASCIZ/ATMIN, with data on DNA/RNA, on the protein encoded and where the gene is implicated.

Keywords Apoptosis, dynein, DNA damage, transcription factor, lung

Identity Other names: ASCIZ, ZNF822

HGNC (Hugo): ATMIN

Location: 16q23.2

Local order: Gene orientation: centromere -5' ASCIZ/ATMIN 3'-telomere. ASCIZ/ATMIN is flanked towards the centromere by CENPN (in the same transcriptional orientiation) and towards the telomere by C16orf46 in opposite transcriptional orientation (NCBI Gene view, gene ID 23300, version 3-Jun-2014).

Note: The gene was originally reported to encode an ATM-substrate Chk2-interacting Zinc-finger protein and referred to by the name ASCIZ in NCBI/Genbank, before the official gene name was changed to ATMIN by HGNC.

DNA/RNA Description The human ASCIZ/ATMIN gene contains five exons over 11497 bases. The main transcript results from splicing of exon A, parts of exon C, and exons D and E and gives rise to the "full-length" protein containing 823 amino acids with four Zinc-fingers. Two alternative transcripts - comprising either exon B, part of exon C and exons D and E, or a longer exon C and exons D and E - give rise to a shorter 667-residue protein with only two Zinc-fingers. The mouse ASCIZ gene structure may be simpler with only four exons and single main mRNA encoding an 818-residue protein similar to the human 4-Zinc-finger product.

Transcription In Northern and Western blot experiments, the two main isoforms of ASCIZ/ATMIN are expressed at relatively similar levels in a wide range of human tissues and all cancer-derived cell lines tested (McNees et al., 2005). Northern blots of various mouse tissues also indicate relatively similar expression levels in a wide range of organs (Jurado et al., 2010).

Diagram 1. Genomic context of the human ASCIZ/ATMIN gene. Numbers indicate the nucleotide positions on chromosome 16 (location 16q23.2). Arrows indicate the 5' to 3' orientation of each gene. Modified from NCBI Map Viewer.

ATMIN (ATM interactor) Heierhorst J


Diagram 2. ASCIZ/ATMIN gene structure and main alternative splice isforms. ASCIZ/ATMIN contains 5 exons (A-E, center) that are spliced to two main open reading frames based on NCBI AceView. The lower splice isoform accounts for ~85% of transcripts collected in NCBI AceView and encodes an 823 amino acid residue protein with four N-terminal Zinc-fingers. The upper splice isoforms represent ~15% of transcripts and encodes a 667 residue protein with two N-terminal Zinc-fingers. Protein coding sequences are indicated by black boxes; non-coding exon sequences are indicated by open boxes; the grey part of exon C contains coding sequences when spliced into the 4-Zinc-finger transcript, but is out-of-frame as part of the 2-Zinc-finger transcript. The asterisk indicates an in-frame stop-codon in the 5'-UTR of the 2-Zinc-finger isoform. The scale bar on top represents 1 kb per notch.

Pseudogene Two ASCIZ/ATMIN pseudogenes have been detected on chromosome 9 (LOC643342) and chromosome 12 (LOC100418940).

Protein Note The human ASCIZ protein occurs in two isoforms. The more abundant long isoform contains 823 amino acid residues with a mass of 88.3 kDa. The shorter isoform contains 667 residues with a mass of 72.3 kDa. The two isoforms are identical except that the first 156 residues (including the first two Zinc fingers) of the longer form are missing in the shorter protein. Mouse ASCIZ contains 818 amino acids and is generally similar to the longer human isoform. Human and mouse ASCIZ exhibit atypical electrophoretic mobility on SDS-PAGE Western blots with an apparent mass of ~115 kDa rather than the predicted ~88 kDa (McNees et al., 2005). The aberrant mobility is unlikely to be caused by post-translational modifications, as similar mobility retardation is also observed with bacterially

expressed recombinant fragments encompassing the SQ/TQ cluster.

Description ASCIZ contains four (or two in the shorter isoform) C2H2 Zinc-fingers at the N-terminus, a so-called core domain, and a C-terminal transcription activation domain. Human ASCIZ contains 20 potential ATM/ATR kinase phosphorylation sites, most of which are clustered in an SQ/TQ cluster domain coinciding with the transcription activation domain (Heierhorst et al., 2011). 11 of these sites are TQT motifs and represent binding sites for the DYNLL1 protein (Rapali et al., 2011; Jurado et al., 2012a).

Expression Based on Western blots, the ASCIZ protein is ubiquitously expressed at similar levels in all mouse tissues, with slightly higher levels in brain and testis (Jurado et al., 2010). Protein expression has not been systematically analysed in human tissues but is expected to be similar to mRNA expression profiles by Northern blots suggesting ubiquitous expression (McNees et al., 2005).

Diagram 3. Topology of the ASCIZ protein. Only the long form is depicted. The shorter form is identical except for lack of the N-terminal 156 residues including the first two Zinc fingers (ZF). Lollipops indicate the 20 SQ/TQ motifs that are potential ATM/ATR kinase phosphorylation sites, including the 11 TQT motif DYNLL1-binding sites in the transcription activation domain.



Localisation The ASCIZ protein is predominantly, if not exclusively, located to the nucleus but not the nucleolus (McNees et al., 2005; Kanu and Behrens, 2007). The protein forms discrete sub-nuclear foci after treatment with methylating and oxidating DNA base damaging agents (McNees et al., 2005; Rapali et al., 2011).

Function ASCIZ was originally identified as an ATM/ATR-substrate and Chk2-interacting protein involved in the DNA base damage response (McNees et al., 2005), and later independently re-isolated as an ATM-interacting protein (Kanu and Behrens, 2007). However, based on recent genetic analyses its main role seems to involve essential developmental functions such as a Zinc-finger transcription factor (Heierhorst et al., 2011). Knockout mice that completely lack Asciz/Atmin die late during gestation (Jurado et al., 2010; Kanu et al., 2010) and exhibit a range of severe organogenesis defects, including most strikingly a complete absence of lungs (Jurado et al., 2010). An N-ethyl-N-nitrosourea (ENU)-generated mouse mutant, gasping-6, that contains a missense mutations of a Zinc-chelating Cys residue in the third Zinc-finger domain of Asciz/Atmin also dies during late gestation with overall similar phenotypic defects to the Asciz/Atmin null mice, including absent or hypomorphic lungs (Goggolidou et al., 2014). Conditional Asciz/Atmin KO mice generated using B lympoid-specific Cd19-Cre (Loizou et al., 2011) or Mb1-Cre (Jurado et al., 2012b) have reduced peripheral B cell numbers due to increased apoptotic cell death during B cell development in the bone marrow. The most highly downregulated gene in Asciz-deficient cells is the dynein light chain subunit Dynll1 (Jurado et al., 2012a). Strikingly, DYNLL1 protein can in turn bind to about a dozen individual sites - mostly encompassing TQT motifs - in the ASCIZ transcription activation domain (Rapali et al., 2011; Jurado et al., 2012a) and thereby inhibit its transcriptional activity in a concentration-dependent manner (Jurado et al., 2012a), which provides a feedback mechanism to maintain stable DYNLL1 protein levels. The ability of ASCIZ to regulate expression of and bind to the DYNLL1-like dynein light chain (called Cutup) is conserved in Drosophila (Zaytseva et al., 2014). The importance of DYNLL1 as an ASCIZ target is highlighted by findings that B cell developmental defects in conditional Mb1-Cre Asciz KO mice can be rescued by ectopic expression of DYNLL1, or simultaneous KO of the pro-apoptotic protein Bim whose activity is inhibited by DYNLL1 (Jurado et

al., 2012b). Likewise, in Drosophila, RNAi knockdown of ASCIZ or Cutup lead to similar developmental defects, which in case of dASCIZ RNAi can be rescued by Cutup overexpression (Zaytseva et al., 2014). The role of ASCIZ in DNA damage responses remains unclear. Loss of ASCIZ leads to increased cell death in response to methylating or oxidating DNA damage in human, mouse and chicken cells (McNees et al., 2005; Oka et al., 2008; Jurado et al., 2010; Kanu et al., 2010), and increased basal IgV gene conversion rates in the chicken DT40 B cell line (Oka et al., 2008). ASCIZ focus formation in response to methylating agents depends on DYNLL1 (Jurado et al., 2012a), but it is not known whether this also involves its transcription factor function. The B cell developmental defect of conditional Asciz/Atmin KO mice could not be rescued by deletion of tp53 or complementation with a pre-arranged B cell receptor transgene (Jurado et al., 2012b), supporting a DNA damage-independent mechanism as cause of the B cell deficiency. ASCIZ was earlier reported to be required for ATM protein stability (and thus termed ATMIN) (Kanu and Behrens, 2007), but this was shown to be incorrect in several subsequent studies (Jurado et al., 2010; Loizou et al., 2011; Zhang et al., 2012). ASCIZ was reported to regulate ATM activation by DNA damage-independent chromatin perturbations (Kanu and Behrens, 2007; Zhang et al., 2012) but this was not confirmed in another study (Jurado et al., 2010).

Homology ASCIZ protein sequences are highly conserved amongst all vertebrates from fish to mammals (Kanu and Behrens, 2007; Jurado et al., 2012a). The ASCIZ protein is structurally and functionally conserved in Drosophila, where it also contains four N-terminal Zinc-fingers and a TQT-rich C-terminal transcription activation domain, condensed into only 388 amino acid residues (Zaytseva et al., 2014).

Mutations Note No specific disease-associated mutations of ASCIZ/ATMIN have so far been reported in humans, but an Asciz/Atmin mis-sense mutation has recently been identified as the cause of the gasping6 (Gpg6) ENU mouse mutant (Goggolidou et al., 2014).

Germinal The gasping6 mouse mutation was isolated in an ENU mutagenesis screen (Ermakov et al., 2009). Asciz/Atmingpg6 mice exhibit exencephaly, edema and absent or small lungs (Ermakov et al., 2009)



and a modest kidney cell polarity defect (Goggolidou et al., 2014). Gpg6 mice contain a point mutation that converts the canonical fourth Zinc-chelating Cys residue in the third Zinc-finger domain to a non-chelating Ser residue (Goggolidou et al., 2014). Dynll1 was the most highly reduced mRNA amongst the analyzed transcripts in affected kidneys (Goggolidou et al., 2014).

Implicated in B cell lymphoma Note Cd19-Cre conditional Asciz/Atmin deletion has been reported to cause B cell lymphoma in ~40% of mice (whose genetic background was not specified) before 1 year of age (Loizou et al., 2011), but deletion via Mb1-Cre (which is more efficient than Cd19-Cre during early B lympoid stages) in C57BL/6 mice did not lead to B cell lymphoma until at least 2 years of age (Jurado et al., 2012b). Irrespective of genetic background, no lymphomas were observed when Asciz/Atmin was deleted in earlier haematopoietic stem/progenitor cells via Mx1-Cre (Jurado et al., 2012b) or Vav2-Cre (Cremona and Behrens, 2014).

Embryonic development/organogenesis Note Germline mutations of Asciz/Atmin in mice lead to late embryonic lethality (Jurado et al., 2010; Kanu et al., 2010; Goggolidou et al., 2014). Mice exhibit exencephaly, complete absence of lungs in the Asciz null mutation or a combination of absent and small lungs in the Asciz/Atmingpg6 point mutant, cardiac defects with oedema, and kidney defects.

Haematopoiesis/B cell development Note Conditional Asciz/Atmin deletion during early B cell developmental stages in mice in the bone marrow leads to peripheral B cell deficiency, which is more severe with Mb1-Cre (Jurado et al., 2012b) than Cd19-Cre (Loizou et al., 2011). Pan-haematopoietic inducible Asciz/Atmin deletion in adolescent mice via Mx1-Cre also leads to a statistically significant but modest and well tolerated anemia (Jurado et al., 2012b).

References McNees CJ, Conlan LA, Tenis N, Heierhorst J. ASCIZ regulates lesion-specific Rad51 focus formation and apoptosis after methylating DNA damage. EMBO J. 2005 Jul 6;24(13):2447-57

Kanu N, Behrens A. ATMIN defines an NBS1-independent pathway of ATM signalling. EMBO J. 2007 Jun

20;26(12):2933-41

Oka H, Sakai W, Sonoda E, Nakamura J, Asagoshi K, Wilson SH, Kobayashi M, Yamamoto K, Heierhorst J, Takeda S, Taniguchi Y. DNA damage response protein ASCIZ links base excision repair with immunoglobulin gene conversion. Biochem Biophys Res Commun. 2008 Jun 27;371(2):225-9

Ermakov A, Stevens JL, Whitehill E, Robson JE et al.. Mouse mutagenesis identifies novel roles for left-right patterning genes in pulmonary, craniofacial, ocular, and limb development. Dev Dyn. 2009 Mar;238(3):581-94

Jurado S, Smyth I, van Denderen B et al.. Dual functions of ASCIZ in the DNA base damage response and pulmonary organogenesis. PLoS Genet. 2010 Oct 21;6(10):e1001170

Kanu N, Penicud K, Hristova M, Wong B, Irvine E, Plattner F, Raivich G, Behrens A. The ATM cofactor ATMIN protects against oxidative stress and accumulation of DNA damage in the aging brain. J Biol Chem. 2010 Dec 3;285(49):38534-42

Heierhorst J, Smyth I, Jurado S. A breathtaking phenotype: unexpected roles of the DNA base damage response protein ASCIZ as a key regulator of early lung development. Cell Cycle. 2011 Apr 15;10(8):1222-4

Loizou JI, Sancho R, Kanu N, Bolland DJ, Yang F, Rada C, Corcoran AE, Behrens A. ATMIN is required for maintenance of genomic stability and suppression of B cell lymphoma. Cancer Cell. 2011 May 17;19(5):587-600

Rapali P, García-Mayoral MF, Martínez-Moreno M, Tárnok K, Schlett K, Albar JP, Bruix M, Nyitray L, Rodriguez-Crespo I. LC8 dynein light chain (DYNLL1) binds to the C-terminal domain of ATM-interacting protein (ATMIN/ASCIZ) and regulates its subcellular localization. Biochem Biophys Res Commun. 2011 Oct 28;414(3):493-8

Jurado S, Conlan LA, Baker EK, Ng JL, Tenis N, Hoch NC, Gleeson K, Smeets M, Izon D, Heierhorst J. ATM substrate Chk2-interacting Zn2+ finger (ASCIZ) Is a bi-functional transcriptional activator and feedback sensor in the regulation of dynein light chain (DYNLL1) expression. J Biol Chem. 2012a Jan 27;287(5):3156-64

Jurado S, Gleeson K, O'Donnell K, Izon DJ, Walkley CR, Strasser A, Tarlinton DM, Heierhorst J. The Zinc-finger protein ASCIZ regulates B cell development via DYNLL1 and Bim. J Exp Med. 2012b Aug 27;209(9):1629-39

Zhang T, Penicud K, Bruhn C, Loizou JI, Kanu N, Wang ZQ, Behrens A. Competition between NBS1 and ATMIN controls ATM signaling pathway choice. Cell Rep. 2012 Dec 27;2(6):1498-504

Cremona CA, Behrens A. ATM signalling and cancer. Oncogene. 2014 Jun 26;33(26):3351-60

Goggolidou P, Hadjirin NF, Bak A, Papakrivopoulou E, Hilton H, Norris DP, Dean CH. Atmin mediates kidney morphogenesis by modulating Wnt signaling. Hum Mol Genet. 2014 Oct 15;23(20):5303-16

Zaytseva O, Tenis N, Mitchell N, Kanno S, Yasui A, Heierhorst J, Quinn LM. The novel zinc finger protein dASCIZ regulates mitosis in Drosophila via an essential role in dynein light-chain expression. Genetics. 2014 Feb;196(2):443-53


Heierhorst J. ATMIN (ATM interactor). Atlas Genet Cytogenet Oncol Haematol. 2015; 19(4):245-248.

Gene Section Review



INIST-CNRS

OPEN ACCESS JOURNAL

CEBPA (CCAAT/enhancer binding protein (C/EBP), alpha) Tian V Tian, Thomas Graf

Gene Regulation, Stem Cells and Cancer Programme, Centre for Genomic Regulation (CRG), Dr Aiguader 88, 08003 Barcelona, Spain (TVT), Universitat Pompeu Fabra (UPF), Dr Aiguader 88, 08003 Barcelona, Spain (TG)


Online updated version : http://AtlasGeneticsOncology.org/Genes/CEBPAID40050ch19q13.html DOI: 10.4267/2042/56435

This article is an update of : Smith LL. CEBPA (CCAAT enhancer binding protein alpha). Atlas Genet Cytogenet Oncol Haematol 2006;10(4):218-221. This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 2.0 France Licence. © 2015 Atlas of Genetics and Cytogenetics in Oncology and Haematology

Abstract Review on CEBPA, with data on DNA/RNA, on the protein encoded and where the gene is implicated.

Identity Other names: C/EBPa, CEBP

HGNC (Hugo): CEBPA

Location: 19q13.1

DNA/RNA Description Human C/EBPα is an intronless gene located on the minus strand of chromosome 19q.

Transcription The C/EBPa mRNA (RNA messenger) consists of a short 5' unstranslated region (5'-UTR), a unique protein coding sequence (CDS) and a long 3'-UTR (Hendricks-Taylor et al., 1992).

Protein Description Human C/EBPα mRNA gives rise to two protein products by using two different translation starting sites (Figure 1 and 2) (Calkhoven et al., 2000). Compared to full-length C/EBPA protein, P42, the shorter P30 isoform lacks N-terminal 117 amino acids (Lin et al., 1993). As a transcription factor, C/EBPA protein consists of DNA-binding domain (DBD) in its carboxyl-terminal (C-terminal), which is conserved between C/ebp family members (Leutz et al., 2011). The highly conserved C-terminus includes the basic DNA binding leucine zipper domain (bZip). The bZip domain in turn consists of a basic region that represents the DNA binding domain (DBD), the fork domain and the leucine zipper domain (LZ). The bZip domain is indispensable for homodimerization and heterodimerization with other members of the C/EBP family.

Figure 1: Human C/EBPa mRNA.

CEBPA (CCAAT/enhancer binding protein (C/EBP), alpha) Tian TV, Graf T


Figure 2: C/EBPa protein domains and interactions.

This region is also involved in the interaction with other transcription factors (e.g. E2F, PU.1, c-JUN, RUNX1 and ETS1) (McNagny et al., 1998; Yamaguchi et al., 1999; Ramji and Foka, 2002; Nerlov, 2004; Koschmieder et al., 2005; Leutz et al., 2011). The N-terminus of C/EBPa consists of three transactivation domains (TA), which can interact with components of the transcriptional machinery (e.g. CBP/P300, TBP/TFIIB) (Nerlov and Ziff, 1995; Kovacs et al., 2003; Schwartz et al., 2003), cell cycle regulators (e.g. E2F, CDK2, CDK4) (Porse et al., 2001; Porse et al., 2006) and chromatin remodellers (e.g. SWI/SNF) (Pedersen et al., 2001).

Expression C/EBPa is mainly expressed in terminally differentiated cells, such as mature adipocytes and myelomonocytic cells. C/EBPa is also found expressed in skin, intestine, lung, adrenal gland, mammary gland, ovary, prostate, placenta (Oh and Smart, 1998; Birkenmeier et al., 1989).

Localisation C/EBPa protein is localized in nucleus.

Function C/EBPa homozygous null mice lack white adipose tissues (Wang et al., 1995), as well as mature granulocytes and granulocyte-macrophage precursors (Zhang et al., 1997; Heath et al., 2004). In addition, forced expression of C/EBPa can direct uncommitted progenitors to differentiate into adipocytes and granulocytes (Freytag et al., 1994; Radomska et al., 1998; Nerlov et al., 1998). Further studies suggest that C/EBPa plays important roles in lineage determination by activating lineage-specific genes (Nerlov, 2004; Graf and Enver, 2009). In hematopoiesis, C/EBPa is one of the key factors driving myeloid cell differentiation from hematopoietic stem cells by interacting with other proteins, such as the ETS family transcription factor PU.1, the ATP dependent chromatin remodeling complex SWI/SNF, the DNA modifying enzyme TET2 (McNagny et al., 1998; Koschmieder et al., 2005; Leutz et al., 2011; Kallin et al., 2012).

Ectopic expression of C/EBPa leads to cell cycle arrest via direct interaction with the key cell cycle regulators CDK2/4 and E2F (Porse et al., 2001; Porse et al., 2006). The N-terminal truncated form of C/EBPa, P30, has been shown to act as a dominant negative regulator of the full-length form, P42. Modulation of P30 expression level in mice can alter normal adipogenesis and granulopoiesis (Kirstetter et al., 2008). Notably, ectopic expression of C/EBPa in B and T-lymphocyte precursors results in transdifferentiation into functional macrophages (Xie et al., 2004; Laiosa et al., 2006; Bussmann et al., 2009; Di Tullio et al., 2011; Kallin et al., 2012). Interestingly, C/EBPa mediated conversion of B lymphoma cells into macrophages impairs significantly its tumorigenicity, providing a novel strategy for lymphoma treatment (Rapino et al., 2013). Moreover, a recent study showed that transient C/EBPa expression is also capable of facilitating the conversion of B cells into induced pluripotent stem cells (iPS cells) (Di Stefano et al., 2014). Moreover, C/EBPa has been shown involved in lung development and airway epithelial differentiation (Cassel et al., 2000a; Cassel et al., 2000b; Cassel et al., 2002). The conditional deletion of C/EBPa gene in respiratory epithelium results in respiratory arrest and death soon after birth. This phenotype is associated with proliferation of immature type II alveolar cells, which causes epithelial expansion and loss of air space (Martis et al., 2006; Basseres et al., 2006).

Homology C/EBPa belongs to the CCAAT/enhancer binging protein family and is highly conserved across vertebrate species. Sequence alignments show that C/EBP members share several conserved regions including the bZip and transactivation domains (Leutz et al., 2011).

Mutations Note Mutations of the C/EBPα gene have been detected in 7%-15% of Acute Myeloid Leukemia (AML) (Pabst et al., 2001b; Preudhomme et al., 2002;



Barjesteh van Waalwijk van Doorn-Khosrovani et al., 2003; Snaddon et al., 2003; Frohling et al., 2004; Lin et al., 2005), around 4% of Myelodysplastic Syndrome (MDS) and Chronic Myeloid Leukemia (CML) (Shih et al., 2005). In addition, two familial cases of AML harboring C/EBPA mutations have been reported (Smith et al., 2004; Renneville et al., 2009).

Germinal Germ line mutations of C/EBPα have been described for two familial cases of AML. In one Inherited acute myeloid leukemia case, a heterozygous deletion of cytosine 212 has been reported (Smith et al., 2004). Recently, the second family contained a heterozygous insertion of cytosine at nucleotide 217 (Renneville et al., 2009). These mutations result in frameshifts, leading to a premature termination of full-length C/EBPa P42 isoform translation. Nonetheless, the alternative C/EBPa P30 isoform translation could be potentially privileged. P30 isoform has dominant-negative activity on the full-length P42 isoform.

Somatic It has been shown that 7%-15% of AML harbor somatic mutations of the C/EBPα gene (Pabst et al., 2001b; Preudhomme et al., 2002; Barjesteh van Waalwijk van Doorn-Khosrovani et al., 2003; Snaddon et al., 2003; Frohling et al., 2004; Lin et al., 2005). In addition, C/EBPα mutations have been detected in MDS and CML patient samples. These mutations can be basically divided into two categories: C-terminal in-frame ins/del mutations altering C/EBPA DNA-binding activities, and N-terminal out-of-frame ins/del mutations impairing translation of full-length P42 isoform and leading aberrant expression of P30 isoform, which has dominant-negative activity on P42 isoform. The majority of leukemias with biallelic C/EBPA mutations harbor one allele with C-terminal mutations and the other one with N-terminal mutations. Tumors with homozygous N'-terminal or C'-terminal mutations are relatively rare.

Implicated in Acute myeloid leukemia (AML) Disease Mutations in C/EBPα have been identified in 7-15% of AML cases (Pabst et al., 2001b; Preudhomme et al., 2002; Barjesteh van Waalwijk van Doorn-Khosrovani et al., 2003; Snaddon et al., 2003; Frohling et al., 2004; Lin et al., 2005). A meta-analysis of a cohort of 1175 patients reported that C/EBPα mutations are preferentially identified in M1, M2 and M4 FAB subtypes and associated with normal karyotype (Leroy et al., 2005).

Prognosis It has been shown that AML patients harboring C/EBPα mutations have favorable prognosis (Preudhomme et al., 2002).

Abnormal protein C-terminal in-frame ins/del mutations can alter C/EBPa DNA-binding activities, and N-terminal out-of-frame ins/del mutations impairing translation of full-length P42 isoform and leading to aberrant expression of P30 isoform, which has dominant-negative activity on P42 isoform (Leroy et al., 2005).

Oncogenesis Mouse models harboring biallelic (C-terminal and N-terminal) C/EBPα mutations suggested that the co-existence of these mutations can increase the proliferation of long-term hematopoietic stem cells (LT-HSC) and override normal HSC homeostasis, leading to expansion of premalignant HSC (Kirstetter et al., 2008; Bereshchenko et al., 2009). Moreover, the fusion oncoproteins AML1-ETO (t(8;21)), CBFb-HYH11 (inv(16)) and PML-RARa (t(15;17)) suppress C/EBPA mRNA expression and/or protein activity in AML (Pabst et al., 2001a; Truong et al., 2003; Cilloni et al., 2003).

B cell precursor acute lymphoblastic leukemia (BCP-ALL) Note t(14;19)(q32;q13)

Disease It has been reported that C/EBPa is involved in several cases of BCP-ALL, although the prevalence of C/EBPa involved translocation need to be determined using larger cohorts (Chapiro et al., 2006; Akasaka et al., 2007; Jeffries et al., 2014). In these BCP-ALL cases, C/EBPa is aberrantly expressed by juxtaposition to the immunoglobulin gene enhancer upon its rearrangement with the immunoglobulin heavy-chain locus.

Oncogenesis Aberrant expression of C/EBPa in BCP-ALL samples harboring t(14;19)(q32;q13) suggests that C/EBPa may have oncogenic function in this disease, which is in contrast to its onco-suppressor role in AML (Chapiro et al., 2006). Further biological studies need to be performed to clarify this hypothesis.

Non-small-cell lung cancer Disease The chromosomal region including C/EBPa was reported deleted in 50% stage II and IIIA lung adenocarcinomas (Girard et al., 2000). However, mutations of C/EBPa in lung cancer are rare. It has been as well reported that an upstream promoter region of the C/EBPa gene is hypermethylated in



approximately 65% of primary lung tumors (Tada et al., 2006). These evidences suggest that C/EBPa is a tumor suppressor in non-small-cell lung cancer.

Oncogenesis Ectopic expression of C/EBPa in lung cancer cell lines results in significant growth arrest (Halmos et al., 2002; Costa et al., 2007). A transcriptional analysis identified that differentiation associated gene FoxA2 is a direct target gene of C/EBPa in lung cancer cell line (Halmos et al., 2004). Recently, using urethane-induced lung cancer model, it has been shown that C/EBPa expression is extinguished through p38alpha MAP kinase inactivation, leading to tumor progression (Sato et al., 2013), confirming a tumor suppressor role of C/EBPa in lung cancer.

Skin squamous cell carcinoma Disease Although C/EBPa expression has been found in human precancerous skin lesions (Actinic Keratoses) and normal epidermis, its expression is undetectable in invasive squamous cell carcinoma samples (Thompson et al., 2011), suggesting a possible role as a tumor-suppressor in skin cancer.

Oncogenesis In normal epidermis, C/EBPa expression is located in basal and suprabasal keratinocytes (Maytin and Habener, 1998; Thompson et al., 2011). Forced C/EBPa expression in a skin cancer cell line inhibits cell proliferation (Shim et al., 2005). Moreover, C/EBPa-null mice are highly susceptible to 7,12-dimethylbenz[a]anthracene- and UVB-induced skin tumor development (Loomis et al., 2007; Thompson et al., 2011). Notably, It has been shown that down-regulation of C/EBPa in skin cancer cells is associated with oncogenic Ras activation (Shim et al., 2005; Loomis et al., 2007).

Prostate cancer Disease It has been shown that C/EBPa expression is down-regulated in prostate cancer sample comparing to normal prostate tissue (Yin et al., 2006). Interestingly, one study showed that C/EBPa expression is sequestered in cytosol, which could impair its transcription factor activity (Zhang et al., 2008). Although further studies need to be performed with larger prostate cancer cohorts for confirmation, these observations suggest an emerging tumor suppressor role of C/EBPa in prostate cancer.

Oncogenesis C/EBPa is mainly expressed in basal layer in normal prostate. In most prostate adenocarcinoma samples, its expression level is low (Yin et al., 2006; Zhang et al., 2008). Forced expression of C/EBPa in prostate cancer cell lines can inhibit

PSA (Prostate Specific Antigen) expression and regulate negatively androgen receptor (AR) signaling (Chattopadhyay et al., 2006; Yin et al., 2006; Zhang et al., 2010). In addition, in AR-negative prostate cancer cell lines, ectopically expressed C/EBPA protein can physically interact with Ku proteins (Ku70, Ku80) and Poly [ADP-ribose] polymerase 1 (PARP-1), conferring prostate cancer cells an increased sensitivity to DNA-damaging agents (Yin and Glass, 2006).

Hepatocellular carcinoma Disease The expression of C/EBPa is reduced in hepatocellular carcinoma samples and higher expression of C/EBPa in hepatocellular carcinoma reversibly correlated with the tumor size and clinical stage (Tomizawa et al., 2003).

Oncogenesis Forced C/EBPa expression in hepatoma cell lines impairs proliferation and tumorigenicity (Watkins et al., 1996). Liver specific C/EBPa knock-in mice are resistant, at least partially, to diethylnitrosamine-induced hepatocellular carcinoma formation. These observations suggest a tumor suppressor role of C/EBPa in hepatocellular carcinoma (Tan et al., 2005).

Head and neck squamous cell cancer Disease It has been reported that C/EBPa expression is down-regulated in squamous cell cancers in head and neck region. This down-regulation correlates with the degree of C/EBPa promoter methylation (Bennett et al., 2007).

References Birkenmeier EH, Gwynn B, Howard S, Jerry J, Gordon JI, Landschulz WH, McKnight SL. Tissue-specific expression, developmental regulation, and genetic mapping of the gene encoding CCAAT/enhancer binding protein. Genes Dev. 1989 Aug;3(8):1146-56

Hendricks-Taylor LR, Bachinski LL, Siciliano MJ, Fertitta A, Trask B, de Jong PJ, Ledbetter DH, Darlington GJ. The CCAAT/enhancer binding protein (C/EBP alpha) gene (CEBPA) maps to human chromosome 19q13.1 and the related nuclear factor NF-IL6 (C/EBP beta) gene (CEBPB) maps to human chromosome 20q13.1. Genomics. 1992 Sep;14(1):12-7

Lin FT, MacDougald OA, Diehl AM, Lane MD. A 30-kDa alternative translation product of the CCAAT/enhancer binding protein alpha message: transcriptional activator lacking antimitotic activity. Proc Natl Acad Sci U S A. 1993 Oct 15;90(20):9606-10

Freytag SO, Paielli DL, Gilbert JD. Ectopic expression of the CCAAT/enhancer-binding protein alpha promotes the adipogenic program in a variety of mouse fibroblastic cells. Genes Dev. 1994 Jul 15;8(14):1654-63

Nerlov C, Ziff EB. CCAAT/enhancer binding protein-alpha amino acid motifs with dual TBP and TFIIB binding ability



co-operate to activate transcription in both yeast and mammalian cells. EMBO J. 1995 Sep 1;14(17):4318-28

Wang ND, Finegold MJ, Bradley A, Ou CN, Abdelsayed SV, Wilde MD, Taylor LR, Wilson DR, Darlington GJ. Impaired energy homeostasis in C/EBP alpha knockout mice. Science. 1995 Aug 25;269(5227):1108-12

Watkins PJ, Condreay JP, Huber BE, Jacobs SJ, Adams DJ. Impaired proliferation and tumorigenicity induced by CCAAT/enhancer-binding protein. Cancer Res. 1996 Mar 1;56(5):1063-7

Zhang DE, Zhang P, Wang ND, Hetherington CJ, Darlington GJ, Tenen DG. Absence of granulocyte colony-stimulating factor signaling and neutrophil development in CCAAT enhancer binding protein alpha-deficient mice. Proc Natl Acad Sci U S A. 1997 Jan 21;94(2):569-74

Maytin EV, Habener JF. Transcription factors C/EBP alpha, C/EBP beta, and CHOP (Gadd153) expressed during the differentiation program of keratinocytes in vitro and in vivo. J Invest Dermatol. 1998 Mar;110(3):238-46

McNagny KM, Sieweke MH, Döderlein G, Graf T, Nerlov C. Regulation of eosinophil-specific gene expression by a C/EBP-Ets complex and GATA-1. EMBO J. 1998 Jul 1;17(13):3669-80

Nerlov C, McNagny KM, Döderlein G, Kowenz-Leutz E, Graf T. Distinct C/EBP functions are required for eosinophil lineage commitment and maturation. Genes Dev. 1998 Aug 1;12(15):2413-23

Oh HS, Smart RC. Expression of CCAAT/enhancer binding proteins (C/EBP) is associated with squamous differentiation in epidermis and isolated primary keratinocytes and is altered in skin neoplasms. J Invest Dermatol. 1998 Jun;110(6):939-45

Radomska HS, Huettner CS, Zhang P, Cheng T, Scadden DT, Tenen DG. CCAAT/enhancer binding protein alpha is a regulatory switch sufficient for induction of granulocytic development from bipotential myeloid progenitors. Mol Cell Biol. 1998 Jul;18(7):4301-14

Yamaguchi Y, Nishio H, Kishi K, Ackerman SJ, Suda T. C/EBPbeta and GATA-1 synergistically regulate activity of the eosinophil granule major basic protein promoter: implication for C/EBPbeta activity in eosinophil gene expression. Blood. 1999 Aug 15;94(4):1429-39

Calkhoven CF, Müller C, Leutz A. Translational control of C/EBPalpha and C/EBPbeta isoform expression. Genes Dev. 2000 Aug 1;14(15):1920-32

Cassel TN, Nordlund-Möller L, Andersson O, Gustafsson JA, Nord M. C/EBPalpha and C/EBPdelta activate the clara cell secretory protein gene through interaction with two adjacent C/EBP-binding sites. Am J Respir Cell Mol Biol. 2000a Apr;22(4):469-80

Cassel TN, Suske G, Nord M. C/EBP alpha and TTF-1 synergistically transactivate the Clara cell secretory protein gene. Ann N Y Acad Sci. 2000b;923:300-2

Girard L, Zöchbauer-Müller S, Virmani AK, Gazdar AF, Minna JD. Genome-wide allelotyping of lung cancer identifies new regions of allelic loss, differences between small cell lung cancer and non-small cell lung cancer, and loci clustering. Cancer Res. 2000 Sep 1;60(17):4894-906

Pabst T, Mueller BU, Harakawa N, Schoch C, Haferlach T, Behre G, Hiddemann W, Zhang DE, Tenen DG. AML1-ETO downregulates the granulocytic differentiation factor C/EBPalpha in t(8;21) myeloid leukemia. Nat Med. 2001a Apr;7(4):444-51

Pabst T, Mueller BU, Zhang P, Radomska HS, Narravula S, Schnittger S, Behre G, Hiddemann W, Tenen DG. Dominant-negative mutations of CEBPA, encoding CCAAT/enhancer binding protein-alpha (C/EBPalpha), in acute myeloid leukemia. Nat Genet. 2001b Mar;27(3):263-70

Pedersen TA, Kowenz-Leutz E, Leutz A, Nerlov C. Cooperation between C/EBPalpha TBP/TFIIB and SWI/SNF recruiting domains is required for adipocyte differentiation. Genes Dev. 2001 Dec 1;15(23):3208-16

Porse BT, Pedersen TA, Xu X, Lindberg B, Wewer UM, Friis-Hansen L, Nerlov C. E2F repression by C/EBPalpha is required for adipogenesis and granulopoiesis in vivo. Cell. 2001 Oct 19;107(2):247-58

Cassel TN, Berg T, Suske G, Nord M. Synergistic transactivation of the differentiation-dependent lung gene Clara cell secretory protein (secretoglobin 1a1) by the basic region leucine zipper factor CCAAT/enhancer-binding protein alpha and the homeodomain factor Nkx2.1/thyroid transcription factor-1. J Biol Chem. 2002 Oct 4;277(40):36970-7

Halmos B, Huettner CS, Kocher O, Ferenczi K, Karp DD, Tenen DG. Down-regulation and antiproliferative role of C/EBPalpha in lung cancer. Cancer Res. 2002 Jan 15;62(2):528-34

Preudhomme C, Sagot C, Boissel N, Cayuela JM, Tigaud I, de Botton S, Thomas X, Raffoux E, Lamandin C, Castaigne S, Fenaux P, Dombret H. Favorable prognostic significance of CEBPA mutations in patients with de novo acute myeloid leukemia: a study from the Acute Leukemia French Association (ALFA). Blood. 2002 Oct 15;100(8):2717-23

Ramji DP, Foka P. CCAAT/enhancer-binding proteins: structure, function and regulation. Biochem J. 2002 Aug 1;365(Pt 3):561-75

Barjesteh van Waalwijk van Doorn-Khosrovani S, Erpelinck C, Meijer J, van Oosterhoud S, van Putten WL, Valk PJ, Berna Beverloo H, Tenen DG, Löwenberg B, Delwel R. Biallelic mutations in the CEBPA gene and low CEBPA expression levels as prognostic markers in intermediate-risk AML. Hematol J. 2003;4(1):31-40

Cilloni D, Carturan S, Gottardi E, Messa F, Messa E, Fava M, Diverio D, Guerrasio A, Lo-Coco F, Saglio G. Down-modulation of the C/EBPalpha transcription factor in core binding factor acute myeloid leukemias. Blood. 2003 Oct 1;102(7):2705-6

Kovács KA, Steinmann M, Magistretti PJ, Halfon O, Cardinaux JR. CCAAT/enhancer-binding protein family members recruit the coactivator CREB-binding protein and trigger its phosphorylation. J Biol Chem. 2003 Sep 19;278(38):36959-65

Schwartz C, Beck K, Mink S, Schmolke M, Budde B, Wenning D, Klempnauer KH. Recruitment of p300 by C/EBPbeta triggers phosphorylation of p300 and modulates coactivator activity. EMBO J. 2003 Feb 17;22(4):882-92

Snaddon J, Smith ML, Neat M, Cambal-Parrales M, Dixon-McIver A, Arch R, Amess JA, Rohatiner AZ, Lister TA, Fitzgibbon J. Mutations of CEBPA in acute myeloid leukemia FAB types M1 and M2. Genes Chromosomes Cancer. 2003 May;37(1):72-8

Tomizawa M, Watanabe K, Saisho H, Nakagawara A, Tagawa M. Down-regulated expression of the CCAAT/enhancer binding protein alpha and beta genes in human hepatocellular carcinoma: a possible prognostic



marker. Anticancer Res. 2003 Jan-Feb;23(1A):351-4

Truong BT, Lee YJ, Lodie TA, Park DJ, Perrotti D, Watanabe N, Koeffler HP, Nakajima H, Tenen DG, Kogan SC. CCAAT/Enhancer binding proteins repress the leukemic phenotype of acute myeloid leukemia. Blood. 2003 Feb 1;101(3):1141-8

Fröhling S, Schlenk RF, Stolze I, Bihlmayr J, Benner A, Kreitmeier S, Tobis K, Döhner H, Döhner K. CEBPA mutations in younger adults with acute myeloid leukemia and normal cytogenetics: prognostic relevance and analysis of cooperating mutations. J Clin Oncol. 2004 Feb 15;22(4):624-33

Halmos B, Bassères DS, Monti S, D'Aló F, Dayaram T, Ferenczi K, Wouters BJ, Huettner CS, Golub TR, Tenen DG. A transcriptional profiling study of CCAAT/enhancer binding protein targets identifies hepatocyte nuclear factor 3 beta as a novel tumor suppressor in lung cancer. Cancer Res. 2004 Jun 15;64(12):4137-47

Heath V, Suh HC, Holman M, Renn K, Gooya JM, Parkin S, Klarmann KD, Ortiz M, Johnson P, Keller J. C/EBPalpha deficiency results in hyperproliferation of hematopoietic progenitor cells and disrupts macrophage development in vitro and in vivo. Blood. 2004 Sep 15;104(6):1639-47

Nerlov C. C/EBPalpha mutations in acute myeloid leukaemias. Nat Rev Cancer. 2004 May;4(5):394-400

Smith ML, Cavenagh JD, Lister TA, Fitzgibbon J. Mutation of CEBPA in familial acute myeloid leukemia. N Engl J Med. 2004 Dec 2;351(23):2403-7

Xie H, Ye M, Feng R, Graf T. Stepwise reprogramming of B cells into macrophages. Cell. 2004 May 28;117(5):663-76

Koschmieder S, Rosenbauer F, Steidl U, Owens BM, Tenen DG. Role of transcription factors C/EBPalpha and PU.1 in normal hematopoiesis and leukemia. Int J Hematol. 2005 Jun;81(5):368-77

Leroy H, Roumier C, Huyghe P, Biggio V, Fenaux P, Preudhomme C. CEBPA point mutations in hematological malignancies. Leukemia. 2005 Mar;19(3):329-34

Lin LI, Chen CY, Lin DT, Tsay W, Tang JL, Yeh YC, Shen HL, Su FH, Yao M, Huang SY, Tien HF. Characterization of CEBPA mutations in acute myeloid leukemia: most patients with CEBPA mutations have biallelic mutations and show a distinct immunophenotype of the leukemic cells. Clin Cancer Res. 2005 Feb 15;11(4):1372-9

Shih LY, Huang CF, Lin TL, Wu JH, Wang PN, Dunn P, Kuo MC, Tang TC. Heterogeneous patterns of CEBPalpha mutation status in the progression of myelodysplastic syndrome and chronic myelomonocytic leukemia to acute myelogenous leukemia. Clin Cancer Res. 2005 Mar 1;11(5):1821-6

Shim M, Powers KL, Ewing SJ, Zhu S, Smart RC. Diminished expression of C/EBPalpha in skin carcinomas is linked to oncogenic Ras and reexpression of C/EBPalpha in carcinoma cells inhibits proliferation. Cancer Res. 2005 Feb 1;65(3):861-7

Tan EH, Hooi SC, Laban M, Wong E, Ponniah S, Wee A, Wang ND. CCAAT/enhancer binding protein alpha knock-in mice exhibit early liver glycogen storage and reduced susceptibility to hepatocellular carcinoma. Cancer Res. 2005 Nov 15;65(22):10330-7

Bassères DS, Levantini E, Ji H, Monti S, Elf S, Dayaram T, Fenyus M, Kocher O, Golub T, Wong KK, Halmos B, Tenen DG. Respiratory failure due to differentiation arrest and expansion of alveolar cells following lung-specific loss

of the transcription factor C/EBPalpha in mice. Mol Cell Biol. 2006 Feb;26(3):1109-23

Chapiro E, Russell L, Radford-Weiss I, Bastard C, Lessard M, Struski S, Cave H, Fert-Ferrer S, Barin C, Maarek O, Della-Valle V, Strefford JC, Berger R, Harrison CJ, Bernard OA, Nguyen-Khac F. Overexpression of CEBPA resulting from the translocation t(14;19)(q32;q13) of human precursor B acute lymphoblastic leukemia. Blood. 2006 Nov 15;108(10):3560-3

Chattopadhyay S, Gong EY, Hwang M, Park E, Lee HJ, Hong CY, Choi HS, Cheong JH, Kwon HB, Lee K. The CCAAT enhancer-binding protein-alpha negatively regulates the transactivation of androgen receptor in prostate cancer cells. Mol Endocrinol. 2006 May;20(5):984-95

Laiosa CV, Stadtfeld M, Xie H, de Andres-Aguayo L, Graf T. Reprogramming of committed T cell progenitors to macrophages and dendritic cells by C/EBP alpha and PU.1 transcription factors. Immunity. 2006 Nov;25(5):731-44

Martis PC, Whitsett JA, Xu Y, Perl AK, Wan H, Ikegami M. C/EBPalpha is required for lung maturation at birth. Development. 2006 Mar;133(6):1155-64

Porse BT, Pedersen TA, Hasemann MS, Schuster MB, Kirstetter P, Luedde T, Damgaard I, Kurz E, Schjerling CK, Nerlov C. The proline-histidine-rich CDK2/CDK4 interaction region of C/EBPalpha is dispensable for C/EBPalpha-mediated growth regulation in vivo. Mol Cell Biol. 2006 Feb;26(3):1028-37

Tada Y, Brena RM, Hackanson B, Morrison C, Otterson GA, Plass C. Epigenetic modulation of tumor suppressor CCAAT/enhancer binding protein alpha activity in lung cancer. J Natl Cancer Inst. 2006 Mar 15;98(6):396-406

Yin H, Glass J. In prostate cancer cells the interaction of C/EBPalpha with Ku70, Ku80, and poly(ADP-ribose) polymerase-1 increases sensitivity to DNA damage. J Biol Chem. 2006 Apr 28;281(17):11496-505

Yin H, Radomska HS, Tenen DG, Glass J. Down regulation of PSA by C/EBPalpha is associated with loss of AR expression and inhibition of PSA promoter activity in the LNCaP cell line. BMC Cancer. 2006 Jun 14;6:158

Akasaka T, Balasas T, Russell LJ, Sugimoto KJ, Majid A, Walewska R, Karran EL, Brown DG, Cain K, Harder L, Gesk S, Martin-Subero JI, Atherton MG, Brüggemann M, Calasanz MJ, Davies T, Haas OA, Hagemeijer A, Kempski H, Lessard M, Lillington DM, Moore S, Nguyen-Khac F, Radford-Weiss I, Schoch C, Struski S, Talley P, Welham MJ, Worley H, Strefford JC, Harrison CJ, Siebert R, Dyer MJ. Five members of the CEBP transcription factor family are targeted by recurrent IGH translocations in B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Blood. 2007 Apr 15;109(8):3451-61

Bennett KL, Hackanson B, Smith LT, Morrison CD, Lang JC, Schuller DE, Weber F, Eng C, Plass C. Tumor suppressor activity of CCAAT/enhancer binding protein alpha is epigenetically down-regulated in head and neck squamous cell carcinoma. Cancer Res. 2007 May 15;67(10):4657-64

Costa DB, Li S, Kocher O, Feins RH, Keller SM, Schiller JH, Johnson DH, Tenen DG, Halmos B. Immunohistochemical analysis of C/EBPalpha in non-small cell lung cancer reveals frequent down-regulation in stage II and IIIA tumors: a correlative study of E3590. Lung Cancer. 2007 Apr;56(1):97-103

Loomis KD, Zhu S, Yoon K, Johnson PF, Smart RC. Genetic ablation of CCAAT/enhancer binding protein alpha



in epidermis reveals its role in suppression of epithelial tumorigenesis. Cancer Res. 2007 Jul 15;67(14):6768-76

Kirstetter P, Schuster MB, Bereshchenko O, Moore S, Dvinge H, Kurz E, Theilgaard-Mönch K, Månsson R, Pedersen TA, Pabst T, Schrock E, Porse BT, Jacobsen SE, Bertone P, Tenen DG, Nerlov C. Modeling of C/EBPalpha mutant acute myeloid leukemia reveals a common expression signature of committed myeloid leukemia-initiating cells. Cancer Cell. 2008 Apr;13(4):299-310

Zhang J, Wilkinson JE, Gonit M, Keck R, Selman S, Ratnam M. Expression and sub-cellular localization of the CCAAT/enhancer binding protein alpha in relation to postnatal development and malignancy of the prostate. Prostate. 2008 Aug 1;68(11):1206-14

Bereshchenko O, Mancini E, Moore S, Bilbao D, Månsson R, Luc S, Grover A, Jacobsen SE, Bryder D, Nerlov C. Hematopoietic stem cell expansion precedes the generation of committed myeloid leukemia-initiating cells in C/EBPalpha mutant AML. Cancer Cell. 2009 Nov 6;16(5):390-400

Bussmann LH, Schubert A, Vu Manh TP, De Andres L, Desbordes SC, Parra M, Zimmermann T, Rapino F, Rodriguez-Ubreva J, Ballestar E, Graf T. A robust and highly efficient immune cell reprogramming system. Cell Stem Cell. 2009 Nov 6;5(5):554-66

Graf T, Enver T. Forcing cells to change lineages. Nature. 2009 Dec 3;462(7273):587-94

Renneville A, Mialou V, Philippe N, Kagialis-Girard S, Biggio V, Zabot MT, Thomas X, Bertrand Y, Preudhomme C. Another pedigree with familial acute myeloid leukemia and germline CEBPA mutation. Leukemia. 2009 Apr;23(4):804-6

Zhang J, Gonit M, Salazar MD, Shatnawi A, Shemshedini L, Trumbly R, Ratnam M. C/EBPalpha redirects androgen receptor signaling through a unique bimodal interaction. Oncogene. 2010 Feb 4;29(5):723-38

Di Tullio A, Vu Manh TP, Schubert A, Castellano G, Månsson R, Graf T. CCAAT/enhancer binding protein alpha (C/EBP(alpha))-induced transdifferentiation of pre-B

cells into macrophages involves no overt retrodifferentiation. Proc Natl Acad Sci U S A. 2011 Oct 11;108(41):17016-21

Leutz A, Pless O, Lappe M, Dittmar G, Kowenz-Leutz E. Crosstalk between phosphorylation and multi-site arginine/lysine methylation in C/EBPs. Transcription. 2011 Jan-Feb;2(1):3-8

Thompson EA, Zhu S, Hall JR, House JS, Ranjan R, Burr JA, He YY, Owens DM, Smart RC. C/EBPα expression is downregulated in human nonmelanoma skin cancers and inactivation of C/EBPα confers susceptibility to UVB-induced skin squamous cell carcinomas. J Invest Dermatol. 2011 Jun;131(6):1339-46

Kallin EM, Rodríguez-Ubreva J, Christensen J, Cimmino L, Aifantis I, Helin K, Ballestar E, Graf T. Tet2 facilitates the derepression of myeloid target genes during CEBPα-induced transdifferentiation of pre-B cells. Mol Cell. 2012 Oct 26;48(2):266-76

Rapino F, Robles EF, Richter-Larrea JA, Kallin EM, Martinez-Climent JA, Graf T. C/EBPα induces highly efficient macrophage transdifferentiation of B lymphoma and leukemia cell lines and impairs their tumorigenicity. Cell Rep. 2013 Apr 25;3(4):1153-63

Sato A, Yamada N, Ogawa Y, Ikegami M. CCAAT/enhancer-binding protein-α suppresses lung tumor development in mice through the p38α MAP kinase pathway. PLoS One. 2013;8(2):e57013

Di Stefano B, Sardina JL, van Oevelen C, Collombet S, Kallin EM, Vicent GP, Lu J, Thieffry D, Beato M, Graf T. C/EBPα poises B cells for rapid reprogramming into induced pluripotent stem cells. Nature. 2014 Feb 13;506(7487):235-9

Jeffries SJ, Jones L, Harrison CJ, Russell LJ. IGH@ translocations co-exist with other primary rearrangements in B-cell precursor acute lymphoblastic leukemia. Haematologica. 2014 Aug;99(8):1334-42


Tian TV, Graf T. CEBPA (CCAAT/enhancer binding protein (C/EBP), alpha). Atlas Genet Cytogenet Oncol Haematol. 2015; 19(4):249-255.

Gene Section Review



INIST-CNRS

OPEN ACCESS JOURNAL

EEF1A1 (eukaryotic translation elongation factor 1 alpha 1) Bruna Scaggiante, Alessandra Bosutti

Department of Life Sciences, University of Trieste, Italy (BS), Department of Medical, Surgical and Health Sciences, University of Trieste, Italy (AB)


Online updated version : http://AtlasGeneticsOncology.org/Genes/EEF1A1ID40407ch6q13.html DOI: 10.4267/2042/56436

This article is an update of : Scaggiante B, Manzini G. EEF1A1 (eukaryotic translation elongation factor 1 alpha 1). Atlas Genet Cytogenet Oncol Haematol 2010;14(4):377-382. This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 2.0 France Licence. © 2015 Atlas of Genetics and Cytogenetics in Oncology and Haematology

Abstract Review on EEF1A1, with data on DNA/RNA, on the protein encoded and where the gene is implicated.

Identity Other names: CCS-3, CCS3, EF1A, EEF1A, EEF-1, GRAF-1EF, LENG7, PTI1

HGNC (Hugo): EEF1A1

Location: 6q13

Local order Distal to LOC100129409, proximal to SLC17A5.

DNA/RNA Description 8 exons, 7 introns (1st intron within 5'UTR), plus a rare optional exon within first intron as found in several ESTs (e.g. emb-CR981691.1, dbj-DC388133.1, dbj-DC406334.1). Presumably a second promoter, about 800 nt upstream of the most common transcription start,

provides an alternative first exon about 320 nt long, as deduced from some ESTs at NCBI (e.g. dbj-DC316623.1, gb-BU173251.1, dbj-DC358918.1). Introns number 2, 3, 4, 6 are phase 0 (between codons), introns number 5, 7 are phase 1 (between 1st and 2nd base of codon). A validated C-G non-synonimous polymorphism has been reported at 1st position of codon 382 (Arg-Gly), plus a few single-hit non-synonimous and some synonymous within CDS. Several others within 3'UTR and introns (SNP source).

Transcription The main processed mRNA encompasses exons 1, 2, 3, 4, 5, 6, 7, 8, this last can be in short or long form. In a few cases also exon 1' is retained. In a few cases exons 1 (and 1') are substituted by the alternative exon from a putative upstream minor promoter, as described above. Moreover, a quite high number of processed transcripts that, after exons 1 and 2, retain intron 2, which introduces a stop codon 22 residues downstream of exon 2 are found (see for instance some of the many ESTs: dbj-DC389722.1, dbj-DC341899.1, dbj-DC414491.1).

Box = exon (blue = 5'UTR, yellow = CDS, light blue = rare optional exon, red = 3'UTR, light red = extended 3'UTR to a downstream polyA signal); line = intron.

EEF1A1 (eukaryotic translation elongation factor 1 alpha 1) Scaggiante B, Bosutti A


Upper boxes, alternating colours: exons (coding part only); lower boxes: protein domains.

Pseudogene About 20 complete or approximately complete intronless pseudogenes, likely generated by retrotransposition, a few of them exempt from frameshifs and with only a few missenses, are present throughout the genome. Two of them harbour a few hundreds nt long insert each, not related to introns of the expressed gene. All of them show a higher homology to EEF1A1 than to EEF1A2. Most of the pseudogenes find an orthologous counterpart within the chimpanzee genome. EEF1AL3 (9q34) (highly homologous); EEF1AL4 (7p15.3) (highly homologous but with 1 frameshift); EEF1AL5-LOC390924 (19q13.12) (contains a 502 nt insert); EEF1AL6 (3q27.1); EEF1AL7 (4q24); EEF1AL8-LOC100132804 (7q35); EEF1AL9 (1p21.3); EEF1AL10-LOC644604 (2q12); EEF1AL11 (5p15.1) (rather highly homologous); EEF1AL12-LOC647167 (1q31.3); EEF1AL13-LOC100130211 (Xq21.2) (lacking about 300 initial codifying nt); LOC124199 (16p12.1) (contains a 307 nt insert); LOC387845 (12p12.3); LOC389223 (4q28.3); LOC401717 (12q12); LOC442709 (7q21.13) (harbours a 21 nt deletion); LOC645693 (15q21.2); LOC645715 (3p22.1); LOC646612 (3q22.3) (lacking about 120 initial codifying nt); LOC728672 (12p12.3); LOC100128082 (5p12).

Protein Note The major form of the protein is 462 residues long, composed by three domains, as shown by the diagram, that relates also the protein domains (lower bar) with mRNA coding exons (upper bar).

Description 462 residues, theoretical MW: 50140.8 Da, theoretical isoelectric point: 9.7. eEF1A1 is one of the alpha subunit forms of the elongation factor 1 complex, that interacts with aminoacylated tRNA and delivers it to the A site of the ribosome during the elongation phase of protein synthesis. The other form is eEF1A2, encoded by a different gene, EEF1A2, located in chromosome 20.

Expression EEF1A1 is constitutively expressed in all tissues, with the exception of adult brain, heart and skeletal muscle, where EEF1A2 expression is found.

Localisation Mostly cytoplasmic, but also nuclear.

Function Canonical function: aa-tRNA delivery to ribosome in mRNA translation The eukaryotic elongation factor 1A (eEF1A1, formerly EF-1alpha or eEF1A) protein belongs to the G-protein superfamily, is one of most abundantly expressed protein in mammalian cells and participates to mRNA translation. It carries aminoacyl-tRNA (aa-tRNA) to the A site of the ribosome as a ternary complex eEF1A1-GTP-aa-tRNA. In mammalian, it is ubiquitously expressed with exception of skeletal muscle, heart and brain where during terminal differentiation eEF1A2 is produced (Knudsen et al., 1993). Moonlighting functions: cytoskeletal remodelling, protein folding and degradation, cell signalling modulation, control of cell growth, apoptosis and cell cycle 1) eEF1A1 and cytoskeletal remodelling. The most relevant non canonical function of eEF1A1 is the modulation of cytoskeleton organization. eEF1A has activity on microtubule severing and bundling. It has a specific site to bind actin that is different from that for the binding of aa-tRNA (Gross and Kinzy, 2005). eEF1A binding to F-actin is modulated by Rho/Rho-kinase pathway. Phosphorylation by Rho kinase decreases the binding of eEF1A1 to F-actin and F-actin bundling. Myosin phosphatase acts in antagonist fashion on eEF1A1 to modulate actin cytoskeletal organization (Izawa et al., 2000). 2) eEF1A1 and protein degradation and folding. eEF1A controls translational fidelity by binding to incorrectly folded proteins but not to correctly folded ones. The incorrectly folded proteins are then directed to degradation pathway (Hotokezaka et al., 2002). eEF1A plays a role in recognition and degradation of co-translationally damaged and ubiquitylated proteins promoting their translocation



to proteasome through interaction with proteasome subunit Rpt1 (Chuang and Madura, 2005). eEF1A exhibits chaperone-like activity by promoting renaturation of enzymes such as aminoacyl-tRNA synthetases, likely contributing to maintain the efficiency of translational machinery (Lukash et al., 2004). eEF1A1 takes part in the aggregosome formation upon proteosome failure by activating heat shock response to degrade uncorrected folded proteins, to favor clearance of protein aggregates and to protect cell from proteotoxicity by favoring autophagy (Meriin et al., 2012). 3) eEF1A1 and control of cell cycle, growth and death. eEF1A as ribonucleoprotein complex, containing a non-coding RNA, binds to and mediates activation of heat-shock transcription factor 1 (HSF1) to protect the cell from heat-shock (Shamovsky et al., 2006). Induction of the non-constitutive eEF1A1 expression in cardiomyocytes as response to lipotoxic ER-stress promotes cell death likely by activation of eEF1A1-dependent cytoskeletal modifications triggering apoptosis (Borradaile et al., 2006). eEF1A1 interacts with the HDM2 gene product at a binding site for eEF1A1 overlaps with that for p53. In normal cells eEF1A1 could promote cell apoptosis by preventing p53 sequestration by HDM2 (Frum et al., 2007). Likely both eEF1A1 and eEF1A2 interacts with the zinc finger protein ZPR1 in response to mitogenic stimuli, redistributing eEF1A1/2 and ZPR1 in the nucleus. This interaction is essential for normal cell proliferation and growth. Thus the interaction eEF1A1/2-ZPR1 is required for normal cell cycle progression (Mishra et al., 2007). eEF1A1 is an interactor of Bood POZ containing gene type 2 (BPOZ-2) that promotes eEF1A1 ubiquitylation and degradation via 26S proteasome. BPOZ-2 inhibits GTP binding to eEF1A1 thus preventing translation. BOPZ-2 is transcriptionally activated by phosphate and tensin homologue deleted on chromosome 10 (PTEN). It has been suggested that PTEN exerts growth inhibition effects in cells not only by antagonizing PI3K-Akt signalling pathway, but also inducing BPOZ-2 expression to degrade eEF1A1. In this manner, in normal cells, the transition from growing to resting phases is mediated by BPOZ-2/eEF1A1 interaction, thus leading to prevention of translation and induction of eEF1A1 degradation by 26S proteasome pathway (Koiwai et al., 2008). eEF1A1 is implicated in a novel cell cycle check-point to prevent tetraploidy in binucleated cells. In tetraploids, cell death, preventing aneuploidy malignancies, is mainly controlled in a caspase-independent manner by the down-regulation of eEF1A1 levels. eEF1A1 mRNA accumulates in specialized P bodies to reduce the expression of the proteins. The prominent signal in the eEF1A1 mRNA for its translational repression

and degradation is in the 5'-UTR. Exogenous expression of eEF1A1 inhibits cell death in tetraploids. Notably, exogenous expression of eEF1A2 whose mRNA 5'-UTR differs from that of eEF1A1 inhibits cell death in tetraploids, thus suggesting another mechanism by which eEF1A2 could promote tumour development (Kobayashi and Yonehara, 2009). Cell adhesion to the extracellular matrix is an essential biological event for cell survival and proliferation in multicellular organisms. Disruption of integrin-mediated cell adhesion leads to a specific type of apoptosis known as anoikis in most non-transformed cells. Recent evidences show eEF1A to act as a membrane receptor for the cryptic anti-adhesive site of fibronectin, which contributes to cell regulation, including anoikis, through negative modulation of cell anchorage. Possibly, the membrane-resident eEF1A may interact with beta1-integrins inactivating their functions in cell adhesion (Itagaki et al., 2012). Down-regulation of eEF1A1 seems to be specific to senescence. Changes in eEF1A expression levels has been proposed also as promising marker for the detection of cellular cancer senescence induced by a variety of treatments, such as ionizing radiation (Byun et al., 2009). 4) eEF1A1 and cell signalling modulation. Besides eEF1A2, in adult mouse neurons eEF1A1 is expressed too and it is able to regulate the recycle of M4 muscarinic acetylcholine receptors (mAChR). Thus, eEF1A1 plays a role in locomotor activity of neurons (McClatchy et al., 2006). eEF1A1 modulates the activities of sphingosine kinases (SK1 and SK2). Phosphorylated and non-phosphorylated eEF1A1 forms interact with phosphorylated and non phosphorylated SK1 and SK2 and this results in an increased enzymatic activity of both SK1 and SK2. In this respect, overexpression of eEF1A1 in quiescent cells has been suggested to play a role in oncogenesis by increasing SK1 and SK2 activities (Leclercq et al., 2008). eEF1A1 is involved in the regulation of vascular function mediated by TNF-alpha. eEF1A1 binds to 3'-UTR of the endothelial nitric oxide synthase (eNOS) to regulate post-translational eNOS mRNA stability. In the human endothelial cell line HUVEC, TNF-alpha-mediated eNOS mRNA destabilization involves eEF1A1 to reduce eNOS mRNA levels (Yan et al., 2008). The different phosphorylation pattern between eEF1A1 and eEF1A2 especially at tyrosine levels has been suggested to determine structural differences of the two isoforms. In particular, eEF1A1 behaves a more extended structure with respect to the more compact one of eEF1A2 (Negrutskii et al., 2012). Phosphorylation of eEF1A1 on serine (S21) and threonine (T88) residues by Raf kinases regulates



eEF1A1 stability. The in vitro phosphorylation of S21 residue in both eEF1A1 and eEF1A2 proteins by Raf kinases is suggested to cause conformational change in the proteins thus impairing GDP/GTP exchange factor interaction and switching the proteins from the protein biosynthesis to the non-canonical functions. Although S21 phosphorylation has not been found in vivo, in eEF1A constructs transfected COS 7 cells, S21 and T88 mutants showed that these sites affect proteins stability. Interestingly, eEF1A1 has a unique phosphorylation site on threonine and tyrosine (T88 and Y86, respectively). Furthermore, phosphorylation deficiency at S21 decreased protein half-time and increased cell apoptosis. Thus modulation of eEF1A1 phosphorylation at S21 is proposed to be implicated in cell proliferation and apoptosis regulation (Sanges et al., 2012). eEF1A1 is involved also in cytokine cell signaling. In particular, TGFβ1 signalling regulates cell proliferation by acting on TβR-I that phosphorylates eEF1A1 at the Ser300 located in the domain for aa-tRNA binding. This impairs protein synthesis and leads to a lower proliferation rate of the cells. Worth of note that this effect is exerted directly on mRNA translation without transcriptional activation (Lin and Souchelnytskyi, 2011). eEF1A1 is also a component of the ribonucleoprotein complex in the transcript-selective translational regulatory pathway mediated by the TGFβ-activated translational element (BAT). BAT is a 33-nt structural RNA element in the 3'-UTR of disabled-2 (Dab2) and interleukin like EMT inducer (ILEI). Dab2 and ILEI are two mRNAs mediating epithelial to mesenchymal transition. TGFβ-induced EMT is essential during embryonic development. In BAT element, eEF1A1 interacts with hnRNP E1 to inhibit translation, blocking the progression of the 80S ribosome by preventing eEF1A1 release from A site following hydrolysis of GTP. In this way the translation is inhibited by the stall at the eEF1A1-dependent elongation stage. Thus eEF1A1 and hnRNP E1 play a fundamental role in EMT by repressing specific gene expression (Hussey et al., 2011). In U343 glioma cells eEF1A1 was found to be the target of heteroalkylketones, compounds that lower interleukin-6 (IL-6) activity in chronic inflammation. By this finding, eEF1A1 was shown to play a critical role in chronic inflammation sustaining IL-6 activity by forming a complex with STAT3 and PKCδ that promotes phosphorylation of STAT3 at serine 727. This in turn triggers NF-kB/STAT3 interaction enhancing IL-6 expression (Schulz et al., 2014). In neurons, both

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