Question

Explain how the abnormal cell division of cancerous cells escapes normal cell cycle controls.

Answer 1

Ans.

• Cancer can be desbribed as a condition of uncontrolled cell division and growth.
• The behaviours of these cancerous cells differ from the normal cells of the body.
• Majority of these differences are reelated with the behaviour of celll division.
• As an example, in comparison to the normal cells, cancer cells are able to multiply even in the absence of growth factors or growth stimulating signal.
• Normal cells require growth factors for their growth.
• The development and progression of cancer is generally associated with a series of modification in the regulators of cell cycle.
• For example, cell cycle inhibitors prevent cell division under harsh growth condition and any malfunction of these inhibitors may lead to cancer.
• In the same manner, overativity of positive regulators of cell division can also lead to cancer.
• Tumor suppressor gene is an example of cell cycle inhibitor and proto-oncogenes are example of the cell cycle promotor.
• Mostly, gene mutations in the cell cycle regulators are responsible for these alteration in their activities.
• Therefore, by ignoring these checkpoints and signals, cancer cells keep dividing without any control.
• This can lead to the production of cells in an overabundant quantity and may form tumors.