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Cards In This Set
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ErbB2 mutations can be especially helpful to cancer cells because ___?
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It interacts with Ras, which is also often mutated
Ras then signals to two different pathways: MAPkinase pathway PI# Kinase (--> PKB) pathwas so double the signalling from a non stimulated receptor |
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List 7 mechanisms by which cancer cells acquire insensitivity to Antigrowth Signals
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1. Down regulation of TGF B receptors (Tumor supressor)
2) Expression of mutant receptors 3. Deletions in Smad 4 (tumor suppressor, without this cell has hard time differentiating) 4. Deletions in Ink4A/B 5. Mutations in CDK4 render is unresponsive to Ink4A/B (so cell can go through synthesis, leading to proliferation) 6. loss of Rb/inactivation of Rb 7. Blocking terminal differentiation signals |
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Ink4A/B
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In = inhibition of cyclin 4A and 4B
-Same as p15/p16? -how related to p53? |
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What are some of the downstream signalling effects of Smad4?
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 Becomes a transcription factor to promote p15/p16 (InkA/B) production Also binds to promotor for plasminogen activator inhibitor thereby preventing plasminogen from aiding in the breakdown of connective tissue/ the ECM |
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What are some of the upstream signalling effectors that affect Smad4?
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TGF B receptors --> Smad3-->Smad3-P --> Smad4--> Smad4-P
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TGF B positively regulates ___?
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Ink4a/b production
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What changes may cancer make to the following proteins:
1. Ink4's or Rb 2. CDK4 3. CyclinD |
1. loss of Ink4's or Rb
2. Mutation of CDK4 can't interact with p16 3. Overexpression of CycD |
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What do Thelper cells display on their surface?
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CD4+
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What are the real surveillance cells for cancer?
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Macrophages (inate!) they directly interact with Thelper cellsCalled the "immunological synapse" because so important
-oldest type of cell in terms of evolution in our immune ss |
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Innate immune cells have receptors that are sensitive to
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Change in shape, allows them to detect pathogenic antigens or damage or danger
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E2F
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 Activator of transcription of proteins needed for DNA synthesis |
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Rb binds to ___?
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 E2F, thereby repressing expression of proteins needed for DNA synthesis |
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P16
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 Inhibits CyclinD/CDK4 (thereby preventing it from releasing E2F from Rb) |
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Which cells are CD8+?
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T Cytotoxic lymphocytes (Tc Cells)
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CD4+ cells release
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Cytokines, which bring in CD8+ and NK cells, which have receptors in response to the information that the macrophage presented to the Thelper cells. It can then recognize abberant cells and cause proapoptitic signals, followed by phagotization
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