Oncogenesis

- Proto-oncogenes found in normal human genomes, have a central role in signal transduction pathway that control cell growth and differentiation
- Mutated proto-oncogenes are called oncogenes (gain of function mutation)
- Examples:
  - Ras oncogenes - rhabdomyosarcoma, sporadic tumor (colon and lungs)
  - c-myc - Burkitt lymphoma
  - N-myc - neuroblastoma
  - SRC - sarcoma

- Tumor suppressor gene requires both copies mutation before tumorigenesis occurs. Mutation results in loss of function
- Examples;
  - NF-1 - neurofibroma
  - BRCA-1 - breast and ovarian cancer
  - Rb - retinoblastoma
  - VHL - von Hippel Lindau
  - p53 - Li Fraumeni syndrome