Neoplasia Flashcards
Three main traits of neoplasia which differentiates it from hyperplasia or repair
Unregulated
Irreversible
Monoclonal - derived from single mother cell unlike hyperplasia - multiple cells dividing
Methods of determining clonality of uterus and B cells
Uterus -G6PD isoforms
B cell - Ig light chain phenotype
Structure of papillary growth
Epithelium, connective tissue core, and central blood vessel
Aflatoxins (from aspergillus) are associated with what neoplasia
Hepatocellular carcinoma
Alkylating agents in chemotherapy increase risk for what neoplasia
Leukemia/lymphoma
Alcohol increases risk with which carcinoma
Squamous cell ca of oropharynx and upper esophagus pancreatic and hepatocellular
Arsenic increases risk for what neoplasia
Squamous cell CA of skin, lung cancer, angiosarcoma of liver
Asbestos increases risk for what neoplasia
Lung carcinoma and mesothelioma
Cigarette smoke is associated with which cancer
Carcinoma of oropharynx, esophagus, lung, kidney, and bladder
Nitrosamines in smoked foods is associated with which carcinoma
Stomach carcinoma
Napthylamine from cigarette smoke increases risk for which neoplasia
Urothelial carcinoma of bladder
Vinyl chloride used to make PVC pipes increases risk for which neoplasia
Angiosarcoma
Nickel, chromium, beryllium, and silica are all associated with what neoplasia
Lung carcinoma
Epstein Barr Virus is associated with which cancers
Nasopharyngeal carcinoma
Burkitt lymphona
CNS lymphoma in AIDS
HHV-8 (Human Herpes Virus 8) is associated with?
Kaposi Sarcoma
Four types of oncogenes
Growth factor
Growth factor receptor
signal transducer
cell cycle regulator
The signal transducer RAS is activated when bound with ___ and deactivated when bound with ___
activated - GTP
deactivated - GDP. Growth factor changes GDP to GTP
Function of p53
Regulates cell cycle from G1 to S
If DNA is mutated, p53 upregulates DNA repair enzymes or induces apoptosis
How does p53 send signal to destroy cell
By activation of BAX, which destroys Bcl2 in mitochondria, causing leakage of cytochrome c and triggering caspaces for apoptosis
How many copies of p53 must be knocked out for tumor formation?
2
Germline mutation of p53 which is associated with increased risk of carcinomas and sarcomas
Li-Fraumeni Syndrome
Function of Rb
Rb is bound to E2F, when Rb is phosphorylated, E2F is released and E2F is required for G1 to S
What phosphorylates Rb?
CyclinD/CDK4 complex
How does tumor avoid immune surveillance
Downregulate MHC I to avoid CD8 destruction
Mechanism of tumor spread
Downregulation of E-cadherin
Cells attach to laminin and destroy BM
Cells attach to fibronectin in ECM and spread locally
Invasion in vessel or lymphatics
Function of E cadherin
Keeps cells tight together and prevent them from escaping basement membrane
In general, which malignancy spreads hematogenous and which spreads lymphatics
Carcinoma - lymph
sarcoma - vessels
Name four carcinomas which spread primarily hematogenously
Kidney, Liver, Choriocarcinoma, Follicular CA thyroid
High nuclear to cytoplasm ration is characteristic of benign or malignant tumors?
Malignant
Low nuclear to cytoplasm ration is characteristic of benign or malignant tumors?
Benign
Vimentin is characteristic of which type of tumors
Mesenchymal origin (sarcoma)
Desmin is characteristic of which type of tumors
Muscle
GFAP is characteristic of which type of tumors
Neuroglia
S-100 is characteristic of which type of tumors
Melanoma
Chromogranin is characteristic of which type of tumors
Neuroendocrine cells (small cell CA of lung, carcinoid)
Mutated gene found in melanomas
p16
Marker associated with cell adhesion and enables malignant cells to metastasize
CD44
