0.00.10.20.30.40.50.60.70.80.91.0

0 6 12 18 24 30 36 42

<24/<24 (n=24)<24/≥24 (n=27)

≥24/≥24 (n=8)

ICAM-1, GRP-78 and NFkB gene polymorphisms associated with clinical outcome in patients with ICAM-1, GRP-78 and NFkB gene polymorphisms associated with clinical outcome in patients with metastatic colorectal cancer treated with first line 5-FU or capecitabine in combination with metastatic colorectal cancer treated with first line 5-FU or capecitabine in combination with

oxaliplatin and bevacizumab (FOLFOX/BV or XELOX/BV)oxaliplatin and bevacizumab (FOLFOX/BV or XELOX/BV)Philipp C. Manegold, Anthony B. El-Khoueiry Georg Lurje, Harpreet Singh, Dongyun Yang,

Wu Zhang, Yan Ning, Alexandra Pohl, Heung M. Chang, Jabi Shriki, Syma Iqbal, and Heinz-Josef Lenz

Department of Medical Oncology, University of Southern California/Norris Comprehensive Cancer Center, Los Angeles, CA

VEGF-targeted, anti-angiogenic therapy has significantly improved therapeutic success in metastatic colorectal cancer (mCRC) patients. However, no predictive or prognostic molecular markers have been identified in association with VEGF-targetd therapy.We evaluated polymorphisms of genes involved in the angiogenesis, cell proliferation, and cell-cell or cell-matrix interaction as potential predictors of clinical outcome in patients with mCRC who received bevacizumab (BV) as part of their frontline therapy. Including: VEGF, VEGF receptor 2, neuropilin 1, epidermal growth factor receptor, Interleukin 6 and 8, adrenomedullin, leptin, fibroblast growth factor receptor 4, tissue factor, matrix metalloproteinases 2,7,9, intercellular adhesion molecule-1 (ICAM-1), glucose related protein 78 (GRP78), and nuclear factor kappa b (NFkB).

Results

Abstract ID: 4134

≥24/≥24: 15.5 months (95% CI: 8.3-20.9+)<24/≥24: 13.9 months (95% CI: 13.0-38.6)<24/<24: 7.8 months (95% CI: 5.3-15.4)(Log-rank, p=0.023)

GRP78 C/T-SNP (rs12009) ►T/T = lower probability of response vs. C/T, C/C = favorable response (p=0.027)

◄ ICAM-1 C/T-SNP (codon K469E, exon 6) T/T = lower probability of response vs. C/T, C/C = favorable response (p=0.032)

A total of 59 patients with metastatic colon cancer treated who received first-line treatment with FOLFOX or XELOX in combination with bevacizumab at the University of Southern California are included in this study (see table). All patients gave informed consent. Patient information was collected through prospective database review and retrospective chart review. The end point of this study was to identify molecular predictors of clinical outcome including response rate and progression free survival (PFS). The PFS was determined by calculating the difference between the date of first treatment and the date of last follow-up appointment or date of progression of disease. Peripheral blood samples were collected from each patient and genomic DNA was extracted from white blood cells using the QiaAmp kit (Qiagen, Valencia, CA). PCR-RFLP assays were performed on genomic DNA extracted from the blood of all 59 patients as previously described.

Genomic polymorphisms of effectors related to inflammatory response, apoptosis and angiogenesis predict clinical outcome in mCRC patients treated with FOLFOX/BV or XELOX/BV.

Baseline characteristics of mCRC patients, n=59Characteristics Frequency Percentage

Median age 56 yrs 29-81 yrs (range)

Gender

Female 23 39

Male 36 61

Treatment

FOLFOX/BV 21 35.6

XELOX/BV 38 64.4

Median follow-up 17.9 months 3.3-28.7 (range)

Progression free survival (PFS) 13.7 months 95% CI: 8.3-16.5

Response

Complete Response (CR) 2 3.4

Partial Response (PR) 35 59.3

Stable Disease (SD) 18 30.5

Progressive Disease (PD) 4 6.8

Introduction Discussion

Est

imat

ed p

rob

abili

ty o

f P

FS

Months since start of FOLFOX/BV or XELOX/BV

NFkB - CA-repeats at 4q23-24 and Progression Free Survival

GRP78 - single nucleotide polymorphism

C/C (n=9) C/T (n=25) T/T (n=25)0

102030405060708090

100

PR66.7%

CR22.2%

SD 11.1%

SD28.0%

PR64.0%

PR52.0%

SD40.0%

PD 8.0%PD 8.0%

The

rape

utic

res

pons

e [%

]

ICAM-1 - single nucleotide polymorphism

C/C (n=11) C/T (n=31) T/T (n=17)0

102030405060708090

100

CR18.2%

PR54.5%

SD18.2%

PD 9.1%

PR71.0%

SD25.8%

PD 3.2%

PR41.2%

SD47.0%

PD 11.8%

The

rape

utic

res

pons

e [%

]

The transcription factor family NFkB has been implicated in cell proliferation and angiogenesis. The main function of NFkB in tumors is to prevent apoptosis and to promote VEGF independent angiogenesis in response to chemotherapy and oxidative stress. Thus, NFkB dependent stress responses have been suggested to mediate resistance of tumors to anti-angiogenic therapy, chemotherapy and radiotherapy [1]. ICAM-1 is pivotal for leukocyte-endothelial cell interaction and initiation of leukocyte-transmigration through the blood vessel wall. The sustained influence of angiogenic growth factor VEGF leads to its down-regulation which results in anergy of the tumor microvasculatur to inflammatory stimuli. Its microvascular anergy might protect the tumor from the host immune response. Anti-angiogenic therapy can reverse the microvascular anergy by normalizing the ICAM-1 expression levels and might therefore promote the host immune response to the tumor. Increased leukocyte infiltration in tumors has been associated with favorable clinical outcome in colorectal cancer patients [2,3]. GRP78 (glucose-regulated protein 78) is a key survival factor in development and cancer. GRP78 expression is induced by cellular stress (glucose starvation, hypoxia) and inhibits pro-apoptotic effectors caspase-7, BIK, and prevents cytochrome c release. High expression levels of GRP78 have been previously associated with poor prognosis in colorectal cancer patients [4,5].

References

Methods

Conclusion

1. De Martin R, Hoeth M et al.(2000) Arterioscler Thromb Vasc Biol 20:e83-e882. Griffioen AW (2008) Cancer Immunol Immunother DOI 10.1007/s00262-008-0524-33. Baeten CI, Castermans K et al. (2006) Clin Gastroenterol Hepatol 4:1351-13574. Lee AS (2007) Cancer Res 67:3496-34995. Xing X, Lai M et al. (2006) Clinica Chimica Acta 364:308-315

Our study on molecular markers in mCRC treated with FOLFOX/Bv or XELOX/Bv revealed significant association of polymorphisms within the CA-repeat sequence at locus 4q23-24 of the NFkB gene with progression free survival (Fig. 1). The single nucelotide polymorphisms within the genes of ICAM-1 (Fig. 2) and GRP78 (Fig. 3) were found to be significantly associated with therapeutic response.

Fig. 1

Fig. 2 Fig. 3