What is Cancer?

How it occurs and cell cycle regulation

What is Cancer?• Cancer = cellular growth disorder that occurs

when cell divide uncontrollably.- Cause carcinogenesis, formation of cancer cells

• Tumor = mass of cancerous cellsCan be:

1. Benign = noncancerous2. Malignant = cancerous and may

spread (metastasis)* Tumors may also promote angiogenesis, the formation of new blood vessels

Metastasis video

How Does Cancer Start?* Cell cycle is regulated by a set of proteins called cyclins.

• They make sure necessary steps completed at each checkpoint.

* Cancer originates when a cell continues to go through cycle even when it shouldn’t.

Cancer Genes• Cancer caused by mutations in genes that

regulate cell cycle.

1. Proto-oncogenes (over 100 known)- proteins that promote cell cycle- mutations lead to oncogenes,

promote cell growth regardless of circumstances.

2. Tumor Suppressor genes (12 known)- proteins that inhibit cell cycle- mutations lead to cell cycle not

stopping even when it should. (p53 and Rb genes)

Can We Find a Cure?Treatments include:

1. Chemotherapy2. Radiation therapy3. Targeted therapy4. Transplantation

For more info on treatments: http://www.cancer.gov/cancertopics/treatment/types-of-treatment

* Key is to find genes linked to cell cycle and develop treatments for their loss or function. (p53 gene linked to over half of all human cancers)