Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
8 Cards in this Set
- Front
- Back
|
Three changes to eukaryotic cells to become tumorigenic?
Mutations or abnormal activation of what causes tumor formation? Mutations in what leads to loss of growth control? |
immortalization - indefinite growth
transformation - loss of regulation metastasis - invade normal tissue proto-oncogenes tumor suppressors |
|
|
Oncogenes - example and activity of:
1. Growth factors 2. GF receptors 3. Signal transducers 4. Transcriptional factors 5. apoptosis regulators |
1. sis- causes PDGF activation
2. Erb B, B2 - seen in breast ca - HER2 - normally on/off, but mutations cause always on 3. functions between GFR and nucleus - Abl - tyrosine kinase (CML), Ras - many cancers 4. act on DNA, control gene transcription - Myc - various cancers 5. when abnormal, prevents apoptosis - Bcl-2 - lymphoma cells |
|
|
Most well-known tumor suppressor gene:
p53 is involved in what? Inherited p53 abnormality: |
p53 - also BRCA1, BRCA2, APC, RB1
cell "suicide" genes - controls apoptosis Li-Fraumeni syndrome (LFS) |
|
|
How do transforming retroviruses work in tumors?
What controls transcription of viral genome? Who discovered the first viral oncogene (src)? Viruses associated with cancer: |
carry cellular genes - post infection, viral RNA transcribed into dsDNA and integrated into genome
LTR sequences Dr. Peyton Rous - 1970 HIV - immunosuppression HTLV-1 - etiologic agent of adult T-cell leukemia |
|
|
HTLV-1:
potent trans-activator of proviral transcription: Why are DNA virus infections and tumors so uncommon? When do they usually happen? |
Tax protein
no survival benefit, causes immune reaction, non-immune responses usually seen in impaired T-cell function |
|
|
Most common mutation in human cancer?
Best known example of anti-apoptosis mechanism in tumors? Causes papillomas, warts, condyloma: Infection with what virus is implicated in increased risk of liver cancer: How is HBV replication unique? |
p53
E1B-19K protein - blocks p53-dependent apoptosis papillomaviruses Hep B virus uses RNA reverse transcriptase |
|
|
Implicated in Burkitt's, post-transplant lymphoma, Hodgkin's, nasopharyngeal carcinoma:
Most common childhood cancer in parts of Africa: Tumorigenic characteristics of EBV? LMP1 mimics what receptor? |
EBV
Burkitt's lymphoma most potent transforming agent known for human cells; carries at least 1 classic oncogene (LMP1 - latent membrane protein 1) TNF receptor |
|
|
Burkitt's lymphoma incidence often coincides with what disease?
CTL response is often directed at what? Defining chromosomal translocation associated with Burkitt's: |
malaria
EBNA-3 proteins c-myc oncogene (8q24) - no regulation of cell proliferation |
