cancer2

• Bcl2 protein

  inhibit apoptosis
• bax protein

  triggers apoptosis
• overexpression of bcl2

  cause too much inhibition of apoptosis even in cancerous cells
• mutation of rb gene (eg of tumor suppressor)

  both copies of rb gene leads to complete loss of tumor suppressor activity leading to cancer
• RB gene

  fuctions at your G1/S checkpoint

  at g1 phase it binds to e2f

  addition of phosphate group to rb releases ur e2f

  free e2f signals cells to divide g1-s phase
• in rb mutant

  rb does not bind to e2f at all

  causing constant transcription leading to increase cell division
• TP53 (tumor supressor)

  controlls G1-S checkpoint

  low conc at end of G1

  if now DNA damge it allow cell to got to s
• APC adenomatous polyposis coli

  Tumor supressor that controls cell to cell contact and growth inhibition
• Xeroderma pigmentosum

  DNA repair defect cause more mutation n increased cancer risks
• familial breast cancer

  brac1 or 2 mutation can defect in dna repair proteins
• Hereditary non polyposis colon cance

  mutation in mismatch DNA repair genes
• Natural carcinogens

  Aflatoxin - mold on bread

  Nitrosamines-meat perservative, pesticides and antibiotics