Cancer Cells
Cancer results from uncontrolled cell division:
- Normal cells stay in the G1 stage of the cell cycle until they are given a specific signal to enter the S phase, in which the DNA replicates and the cell prepares for division. Cancer cells enter the S phase without waiting for a signal.
- Normal cells are mortal. This means that they can divide about 50 times and then they lose the ability to die. Cancer cells escape this process of mortality: they are immortal and can divide endlessly.