Week 8

when cells grow into or detach and crawl into adjoining tissue.

• Cell becomes less responsive or unresponsive to external differentiation and death signals • Cell becomes more responsive to survival, growth and division signals (such as EGF) • ability to disperse (metastasize) • increased mutation (evade regulation)

epidermal growth factor - protein that stimulates cell growth and differentiation by binding to its receptor, EGFR.

unrepaired DNA damage is the signal

Excess cells and virus-infected cells are detected by other cells and signalled to die by apoptosis

tumor suppressor gene encodes p53 protein

• Detect and respond to DNA damage • Stop cell proliferation (division and growth) to permit time for DNA repair • If DNA repair fails, they induce or initiate cell death

p53, pRb, p21

mutated genes that can cause cancer by causing cells to grow and divide uncontrollably

their masses kda/ kilodaltons

retinoblastoma protein

p53 inhibitor

complex process that activates the tumor suppressor protein p53 in response to DNA damage

X-rays, gamma rays & alpha particles

“kinases” & “phosphorylation” • Kinases add PO4- (phosphate) to proteins

kinases that phosphorylate p53 gene

EGF binding to EGF-R causes shape change that lets EGF-R bind to and transfer phosphate from ATP to itself

phosphatases remove phosphates

mitogen activated kinase

helps treatment (invasion and metastasis)

ATP and GTP

proteins that later the frequency with which a gene is transcribed (expressed)

cancer cell invasion and metastasis