Question

Cancer is not a contagious disease instead, it is an error in cellular regulation.
Why is it that cancer can spread so quickly throughout a living organism?

• A. Some cancer cells can produce their own growth factor to pass cell cycle checkpoints.
• B. Cancer cells reproduce by going through the phases of the cell cycle in the wrong sequence.
• C. Cancer cells are developed by natural selection due to overuse of antibiotics.
• D. Cancer cells spend most of their time in the G${}_0$ phase of the cell cycle.

Answer 1

The correct option is A Some cancer cells can produce their own growth factor to pass cell cycle checkpoints.

Cell cycles are regulated by cyclins and Cyclin dependent kinases (CDK). In cancer cells this regulatory mechanism is lost, thus the cells divide or proliferate in an uncontrolled manner after a certain stage, they produce growth factors and respond to them in an autocrine manner. Since, they are the body cells they are not destroyed by the immune system. They are capable of separating from the parent tumor and establishing else where in the body, a process called metastasis.

So, the correct answer is 'Some cancer cells can produce their own growth factor to pass cell cycle checkpoints'