Question

1) (2 pt) Two unrelated individuals are diagnosed with skin cancer. Do both of these people have the exact same disease? - explain using a cell cycle explanation of what cancer is. Reflect on your Answer to #1 : going ½ point each, WHY you think yo answer deserves to get these points

Answer 1

No, both of them may not have the same exact type of skin cancer. There are three type of skin cancers -

• Basal-cell skin cancer (BCC) - They slowly and damage the tissue around it but they do not spread to distant areas or result in death.
• Squamous-cell skin cancer (SCC) - They form a hard lump with a scaly top that spread.
• Melanoma - a mole that has changed in size, shape, color, has irregular edges, has more than one color, is itchy or bleeds.

Cancer is caused by uncontrolled cell division. Tumor development and progression are linked to a series of changes in the activity of cell cycle regulators.

Mutations in positive regulators (proto-oncogene) of cell cycle overactivates the cell division to become oncogenic. Proto-oncogenes are genes that normally help cells grow. When critical functions are altered and malfunctioning, activated oncogenes can cause those cells to proliferate out of control.

Mutations in negative regulators (tumor supperssors gene) will inactivate them and cells grow out of contol leading to cancer. Tumor suppressor genes are normal genes that slow down cell division, repair DNA mistakes, or cause apoptosis or programmed cell death.