Chapter 2: The Nature of Cancer of tumors are of epithelial origin.

- These types of tumors are called .

List the 5 functions of epithelial cells:1. 2. 3. 4.5.

The , also called the basement membrane, is a specialized ECM meshwork that sit on top of and anchor to.

The exists beneath the and provides the bulk of tissues and organs.

Epithelial cells derive from which of the 3 embryonic germ layers? (Check all that apply)Ectoderm Mesoderm Endoderm

The term polarized explains that the apical side and basal side of epithelial cells have different functions.

- The apical side faces the . - The basal side is in contact with .

Tight junctions, adherens and desmosomes join epithelial cells to .

True/False: Tight junctions between epithelial cells completely seal off one compartment from another.

The proteins used to form tight junctions are and .

Compare and contrast adherens junctions to desmosomes:

Cadherins provide a positive/negative regulation of growth and allow for communication between cells.

Hemidesmosomes anchor epithelial cells to the basal lamina.

Cells don’t attach directly to collagen, they attach to which attaches to cells and also to collagen.

Integrins are that allow cells to communicate between and of the cell by signal transduction. They also interact with the .

- If the ability of a normal cell’s integrins to bind with its ligands was blocked, the cell would proliferating because it no longer has contact with the .

Match the following term with its definition:

Hyperplastic a) normal phenotype but increased number of cellsMetaplastic b) normal phenotype but in wrong locationMetastatic c) less differentiated and more proliferativeNeoplastic d) dedifferentiated, proliferative and invasiveDysplastic e) capable of forming a new tumor

Fill in the progression of cancer development:

Fill in the missing terms:

Neoplastic = = = = “Cancer”

*Intraepithelial neoplasia=dysplasia…meaning, the cells are decreasingly differentiated and increasingly more proliferative, however, they haven’t broken through the basal lamina and into the stroma, remaining in the epithelial space and thus, dysplastic.

Tumors derive from cell(s), making them .-Observations support this theory, however, definitive proof has not been found because cancers develop gradually over time and cancer cells are genetically unstable.

All of cancer cells descend from the cell in which the occurred.

Put the following words under the correct term:Anchorage-dependent, contact-inhibited, immortal, mitogen-dependent, refractile, round, tumorigenic

Normal Cells Transformed Cells

Which factor has a greater influence on cancer rates—genetics or environment? (What study supports this?)

The was developed to determine mutagenic a substance was. The scientist that developed this is .

- A more sophisticated version of the Ames test was developed to determine how mutagenic these substances are in our body after being broken down by the . Thus, this test used substances that have been worked on by liver . * Prior to Ames’ work, Yamagiwa recognized that certain compounds were capable of inducing cancer in rabbits when applied repeatedly.

Chapter 3: Tumor Viruses

Describe the protocol that Peyton Rous used for inducing sarcomas in chickens:

A focus formed in tissue culture is the equivalent of a .

List 4 characteristics of transformed cells:1. 2. 3. 4.

“Nude mice” essentially have no system. This allows them to cells from different species.

For a virus to transform cells, it must its own DNA into the host cells genome.- An RNA virus does this by

A retrovirus contains , which converts their genomes into double stranded DNA.

True/False: The src proto-oncogene is apparently found in all multicellular eukaryotes.

Explain how src became part of the viral genome.

Why/how does this lead to tumorigenesis?

While src is over expressed in chicken carcinomas, src is/is not commonly deregulated in human cancers.

What are the 2 changes that can occur that make a proto-oncogene become an oncogene?1. 2.

A proto-oncogene is a eukaryotic cell, that when deregulated, becomes an .

What process does the following describe? - DNA from a transformed cell is inserted into a normal cell by gene transfer (transfection)

Insertional mutagenesis explains how infection may first present with a typical viral phenotype and later, over time, become .

The integration of a virus upstream of myc will result in the up regulation of that gene and lead to .