Proto-oncogenes

What role do proto-oncogenes play in cell division?

Proto-oncogenes initiate mitosis, and gain-of-function mutations in these genes can result in oncogenes, contributing to cancer.

How many copies of an oncogene are required for cancer development?

Only one copy of an oncogene is needed for cancer development.

What is the role of tumor suppressor genes in the cell cycle?

Tumor suppressor genes stop mitosis if DNA damage is detected or if proper cell signaling has not occurred.

How do mutations in tumor suppressor genes contribute to cancer?

Loss of function mutations in tumor suppressor genes can lead to cancer, and both copies of the gene must be mutated for cancer to develop (two-hit hypothesis).

What are tumor-associated antigens?

Tumor-associated antigens are overexpressed or inappropriately expressed proteins found in tumor cells.

What are tumor-specific antigens?

Tumor-specific antigens are antigens expressed exclusively by tumor cells, often including virus-encoded proteins.