Cancer cells differ from normal cells in many ways.
The most widely recognized characteristic of the cancer cell is its uncontrolled cell division. I will deal here with the changes that occur in the cell cycle, to illustrate some of the ways in which normal cells become cancer cells. The Cell Cycle Cells actively cycle and divide at various times during the life of an organism. At the beginning of an organism's life, cells divide rapidly to support tissue and organ growth. When the organism reaches maturation, most cell types stop cell division and enter a resting phase known as G0.