The right answer is Growth rate.
To increase its rate of growth and multiply constantly, cancer cells bypass many regulations of cell proliferation, which leads them to proliferate uncontrollably. These cells have several solutions to prevent senescence.
For a cell to proliferate, the critical point it must pass through the cell cycle is the restriction point maintained by the Rb protein. Proliferation signals must be sustained to inactivate this control point as the rest of the cell cycle progresses without external stimulation. To proliferate excessively, the cancer cells thus overactivate the cell proliferation signals to pass the restriction point as quickly as possible. They use several strategies to over-activate these signals.
