What role do tumor-suppressor genes play in the regulation of cell growth?

What role do tumor-suppressor genes play in the regulation of cell growth?

• A. They promote cell division
• B. They repair DNA damage
• C. They inactivate growth-promoting factors
• D. They accelerate apoptosis

Answer: (C)

Tumor-suppressor genes play a crucial role in regulating cell growth by inactivating growth-promoting factors. These genes encode proteins that are involved in controlling the cell cycle and ensuring that cells do not grow and divide uncontrollably. When functioning properly, tumor-suppressor genes can effectively halt the transition of a cell from one phase of the cell cycle to another, allowing time for DNA repair or inducing apoptosis if the damage is irreparable. Inactivation of growth-promoting factors helps to maintain a balance in cell proliferation, preventing excessive growth that could lead to tumor formation. For instance, the well-known tumor-suppressor gene p53 is responsible for regulating the cell cycle and can trigger cell arrest to allow for DNA repair, thereby inhibiting potential cancer development. The other options do have related functions but do not specifically highlight the primary role of tumor-suppressor genes in the context of growth regulation. While repair of DNA damage is a crucial process where tumor-suppressor genes may have a role, it is not their direct contribution to growth regulation. Similarly, promoting cell division and accelerating apoptosis do not align with the fundamental function of tumor-suppressor genes, which is more about controlling and inhibiting excessive growth rather than promoting or hast

Tumor-suppressor genes play a crucial role in regulating cell growth by inactivating growth-promoting factors. These genes encode proteins that are involved in controlling the cell cycle and ensuring that cells do not grow and divide uncontrollably. When functioning properly, tumor-suppressor genes can effectively halt the transition of a cell from one phase of the cell cycle to another, allowing time for DNA repair or inducing apoptosis if the damage is irreparable.

Inactivation of growth-promoting factors helps to maintain a balance in cell proliferation, preventing excessive growth that could lead to tumor formation. For instance, the well-known tumor-suppressor gene p53 is responsible for regulating the cell cycle and can trigger cell arrest to allow for DNA repair, thereby inhibiting potential cancer development.

The other options do have related functions but do not specifically highlight the primary role of tumor-suppressor genes in the context of growth regulation. While repair of DNA damage is a crucial process where tumor-suppressor genes may have a role, it is not their direct contribution to growth regulation. Similarly, promoting cell division and accelerating apoptosis do not align with the fundamental function of tumor-suppressor genes, which is more about controlling and inhibiting excessive growth rather than promoting or hast