Cell Cycle Question 2

Cancer can result from a variety of different mutational events. Which of the following is LEAST likely to result in the initiation of a cancerous tumor?

A receptor mutation results in activation of a cell-division pathway in the absence of the appropriate ligand.

A mutation results in the loss of the ability to produce a tumor-suppressor protein.

A defect in a cell-cycle checkpoint prevents a cell from entering the S phase.

At the anaphase checkpoint, separation of chromatids occurs without all centromeres being attached to kinetochore microtubules from both poles.