Cancer cells often have hundreds of mutations. What are the first few starting mutations that give growth advantage to a cancer cell called?
A) Driver mutations
B) Passenger mutations
C) Carrier mutations
D) Indirect mutations
E) Induced mutations
The correct answer and explanation is:
The correct answer is A) Driver mutations.
Driver mutations are the initial mutations that provide cancer cells with a growth advantage. These mutations are crucial because they directly contribute to the transformation of normal cells into cancerous cells. These mutations typically occur in genes that regulate cell growth, division, and survival. The mutations can affect oncogenes, tumor suppressor genes, or genes involved in DNA repair mechanisms. Driver mutations play a key role in cancer development and progression by enabling cells to bypass normal growth controls, resist cell death, or promote other characteristics of cancer cells, such as increased angiogenesis (formation of new blood vessels) or metastasis (spread to other tissues).
These mutations are typically selected for during cancer progression, as they confer a survival or proliferative advantage to the cancer cells. For example, mutations in the TP53 gene (which codes for the tumor suppressor protein p53) are common driver mutations. When this gene is mutated, cells lose their ability to repair DNA damage or undergo apoptosis, allowing for the accumulation of further genetic mutations.
Passenger mutations, on the other hand, are mutations that accumulate in cancer cells but do not provide a selective advantage. These mutations are generally considered “passengers” because they do not directly contribute to cancer development but instead occur as a result of the genetic instability associated with the tumor. While they may be numerous, passenger mutations are not the driving force behind cancer growth.
The identification of driver mutations is crucial for understanding cancer biology and for developing targeted therapies that specifically address these key mutations in the cancer cells.