Flashcards in CH3 - Principles of Neoplasia Deck (169)
Squamous cell carcinoma of skin, lung cancer, and angiosarcoma of liver. Arsenic is present in cigarette smoke.
Lung carcinoma and mesothelioma. Exposure to asbestos is more likely to lead to lung cancer than mesothelioma.
Carcinoma of oropharynx, esophagus, lung, kidney, and bladder. Most common carcinogen worldwide; polycyclic hydrocarbons are particularly carcinogenic.
Stomach carcinoma, Found in smoked foods, responsible for high rate of stomach carcinoma in japan
Urothelial carcinoma of bladder. Derived from cigarette smoke
Angiosarcoma of liver, occupational exposure; used to make polyvinyl chlurkle (PVC) for use in pipes
Nickel, chromium, beryllium, or silica
Lung carcinoma Occupational exposure
EBV, HHV-8, HBV and HCV, HTLV-1, High-risk HPV
Nasopharyngeal carcinoma, Burkitt lymphoma and CNS lymphoma in AIDS
HBV and HCV
Adult T-cell leukemia/lymphoma
High-risk HPV (e.g. subtypes 16, 18, 31, 33)
Squamous cell carcinoma of vulva, vagina, anus, and cervix; adenocarcinoma of cervix
(nuclear reactor accidents and radiotherapy) AML, CML and papillary carcinoma of the thyroid. Generates hydroxyl free radicals.
Non Ionizing (UVB sunlight is most common source)
Basal cell carcinoma, squamous cell carcinoma, and melanoma of skin
Non Ionizing radiation results in?
formation of pyrimidine dimers in DNA, which are normally excised by restriction endonuclease
Ras Receptor binding causes
GDP to be replaced with GTP, activating ras.
What does activated ras do?
sends growth signals to the nucleus
How is Ras deactivated?
inactivates itself by cleaving GTP to GDP; this is augmented by GTPase activating protein
inhibits the activity of GTPase activating protein. This prolongs the activated state of ras, resulting in increased growth signals.
Cell cycle regulators mediate what?
progression through the cell cycle (e.g. cyclin and cyclin-dependent kinase).
Cyclins and cyclin-dependent kinases (CDKs) do what?
form a complex which phosphorylates proteins that drive the cell through the cell cycle.
The cyclin D / CDK4 complex does what?
phosphorylates the retinoblastoma protein, which promotes progression through the G-S checkpoint
What do tumor supressor genes do?
Regulate cell growth decreasing (suppress) the risk of tumor formation;
What are some classic examples of tumor supressor genes?
p53 and Rb (retinoblastoma)
What does p53 regulate?
progression of the cell cycle from G to S phase
In response to DNA damage, what does p53 do?
slows the cell cycle and upregulales DNA repair enzymes.
Platelet-derived growth factor, overexpression, autocrine loop, astrocytoma
FRBB2 [HER2f neu]
Epidermal growth factor receptor, Amplification mechanism, Subset of breast carcinomas