Most cancers require at least two mutations: 1) one in an oncogene, which encodes proteins that trigger cell division, and 2) one in a tumor suppressor gene, whose protein products, in their unmutated form, play a key role in preventing the cell cycle from progressing if the DNA is damaged or in the absence of specific cues. Which class of proteins might be considered tumor suppressors?
A) Cdk inhibitors
B) cyclins
C) growth factor receptors
D) microtubules
E) transcription factors

Question

Quizplus · Accepted Answer

Cdk (cyclin-dependent kinase) inhibitors are proteins that can halt the cell cycle, thereby acting as a checkpoint against uncontrolled cell division. This function aligns with the role of tumor suppressors, which prevent the cell cycle from progressing under conditions of DNA damage or in the absence of specific growth signals.

Most Cancers Require at Least Two Mutations: 1) One in an Oncogene