Biology of Cancer Flashcards
DNA damage is not a mutation until when?
Translation
HNPCC is due to what type of DNA defect?
Mismatch repair
Ataxia telangiectasia is due to what type of DNA defect?
ATM gene - DNA damage recognition
BRCA-1,2 (predisposition to breast cancer) is due to what kind of DNA defect?
repair by homologous recombination
Xeroderma pigmentosum is due to what kind of DNA defect?
Nucelotide excision repair (NER)
These cells are anchor independent, resistant to senescence, and resistant to apoptosis
Malignant cells
This results from gain of function mutations of a growth promoting gene
Oncogene
Normal genes that encode growth-inhibiting products that show loss of function in cancer cells
Tumor suppressor genes
c-onc refers to
proto-oncogenes
Ras stimulates what pathway, which in turn activates transcription?
MAP kinase cascade
When Ras remains activated, how does this effect the cell cycle?
Mitosis is activated and remains activated
What is bound to Ras to activate it?
GTP
What is the tumor suppressor that is responsible for turning off the Ras complex?
NF-1 (neurofibromin)
Rb binds to what protein to arrest the cell cycle from inappropriate proliferation?
E2F
Tumor Suppressor Gene for Retinoblastoma
Rb
Rb regulates what cell cycle checkpoint?
G1/S
Transcription factor that regulates cell cycle, DNA repair, and programmed cell death
p53
What is the most frequent mutation leading to cancer?
p53
Li Fraumeni syndrome is a genetic defect in what transcription factor?
p53
This factor determines breast cancer prognosis
p27
Low levels of p27 in breast cancer patients show what kind of outcome?
poor
Sporadic colon cancer is due to a mutation in what?
APC (adenomatous polyposis coli)
The death receptor pathway is activated by
initiator and execution caspases
Philadelphia Chromosome is due to a rearrangement in what 2 chromosomes
9:22
95% of all CML patients contain what?
The Philadelphia Chromosome
The Philadelphia Chromosome translocation creates a fusion of what two proteins?
bcr-abl
abl is what type of proto-oncogene?
tyrosine kinase
The presence of c-myc gene puts a patient at a greater risk for what myeloproliferative disease?
Burkitt’s Lymphoma
The N-myc gene is present in what disease?
Neuroblastoma
The proto-oncogene occurs as double-minutes when activated
N-myc
Methotrexate targets what synthesis?
thymidylate synthase in purine synthesis
Cyclophosphamide and cisplatin are what kind of DNA damaging agent?
Alkylating agents
Alklyating agents, used in cancer treatment, damage DNA so heavily it triggers what?
Apoptosis
Gleevac (Imatinib) binds what oncogenic protein and inactivates it?
bcr-abl tyrosine kinase
Gleevac would be used to treat what disease?
CML