Cell Cycle and Cancer

• Proteins responding to internal and external cell events regulate the phases of the cell cycle.
• The G1 phase is when cells grow, repair DNA damage, and prepare for replication.
• G2 phase is where proteins are made that will be used during mitosis
• During S-phase, DNA synthesis occurs.
• Mitosis is the division of chromosomes into two daughter nuclei.
• Cytokinesis is where cytoplasm divides into two new cells
• Cancer involves the uncontrolled growth of cells
• Tumor cells need additional oxygen and nutrients.
• Tumor cells release tumor angiogenesis factors (TAF)
• Angiogenesis is the growth of new blood vessels.
• Carcinogens cause cancer.
• P53 is a cell cycle regulating protein. It is responsible for stopping growth if there is a problem with DNA.
• Cyclins are proteins that cause the cell to continue with the cell cycle. They give a signal to move on to the next page.
• P3 controls the expression of cyclins.
• Metastasis is the spread of cancer cells from the original site of cancer to other parts of the body.
• Leukemia and lymphoma get into the lymphatic/circulatory system and now can spread anywhere.
• Cancer treatments include the tumor being surgically removed, radiation therapy, and chemotherapy
• During apoptosis, the cell shrinks and pulls away from neighbors. The surface of the cell appears to boil, fragments breaking away in bubbles. DNA in nucleus condensed and breaks into fragments. Then the nucleus disintegrates, following with the cell.
• Apoptotic bodies contain enzymes that digest the cell's own contents.
• As an organism grows, new cells must be created.
• Necrosis is the premature death of cells and living tissue.
• As a cell grows, if it gets too big, it is hard to get enough materials into cell to meet cells needs.
• Stem cells - a special type of cell - non-specialized cells that divide to produce various specialized cells (ex: bone narrow cells which produces red and white blood cells)
• Cell differentiation - process by which stem cells become more specialized