Cell cycle & tumor suppressors
What are the stages of the cell cycle?
G1 (G0) -> S -> G2 -> Mitosis
What is P53?
Enzyme of chromosome 27 that checks everything for errors in cell prodcuction.
What is apoptosis?
Programmed cell death.
What is metastasis?
The process of cancer cells breaking away and moving to other parts of the body.
What is the definition of Angiogenesis?
When tumors causes the development of new blood vessels to the tumor in order to receive more nutrients.
What are the tumor suppressors?
Cyclin and CDK.
What are the checkpoints in the cell cycle for Cyclin and CDK?
Late G1 phase, mid-S phase, and mid-G2 phase.
What is one trigger of apoptosis?
Cell shrinkage, fragmentation of cell DNA, cell breakage, other errors during production of a cell.
What does MMP do?
Degrades the collagenous extracellular matrix and goes through basement membrane surrounding the tumor allowing access to the lymph system and blood stream.
In VEGF, what does GF stand for?
Growth factor.
What do tumor suppressors do to suppress tumors?
They phosphorylate enzyme to ensure organelles have been properly replicated.
Where in the cell cycle are P53 checkpoints?
Beginning of S-phase and before mitosis/late-G2 phase.
What pathways facilitate apoptosis?
Intrinsic and extrinsic pathway.
What is MMP and where does it come from?
Matrix metalloproteinase enzyme; secreted by malignant cells.
What are chimeric antibodies?
What happens in G0 phase and G1 phase?
G0- Resting phase (where cells don't die or grow)
G1- cell growth/replication
If P53 finds an error right before mitosis, what does it do?
It sends a signal to commence apoptosis.
What do cancer cells do to stop apoptosis?
They inhibit their intrinsic and extrinsic pathways.
How do malignant cells travel?
They migrate by breaking cell membrane vessels.
What stimulates the growth of blood vessels towards the tumor?
Secretion of VEGF to the tumor.
What happens in S phase and G2 phase?
S- DNA synthesis
G2- More cell growth
What inhibits cyclin and CDK?
P21, P27, P57 (repair signals).
What problem is causes by the inhibition of apoptosis?
Unregulated cell growth.
What do the aggressive malignant cells do?
They enter blood vessels and travel to other organs.
What is the process of Angiogenesis?
Malignant cells excrete VEGF -> Blood cells want VEGF so they grow towards the tumor -> VEGF stimulates growth of blood vessels