Question

'Cancer' may be described as a progressive disease. What are some of the changes that may be observed in cells, and their sites in the body, which lead to cancer? Why is this important to understand?

Answer 1

• Cancer is one of the most deadly disease of Human beings and also the major cause of death all over the world.
• As we know cell division, cell growth and cell differentiation is highly controlled and regulated in any organism. A variety of hormones and factors are involved in the regulation of these complicated processes.
• But in these cancer cells, there is breakdown of these regulatory mechanisms which leads to the the uncontrolled growth of these cells leading to the tumor and hence causing cancer condition.

Now let us discuss how cancer cells are different from normal cells.

1. Contact inhibition:-  Normal cells show the process of contact inhibition, i.e. Cells come in contact with each other and inhibits their uncontrolled growth. But cancer cells have lost this property and as a result cancerous cells just continue to divide nad show uncontrolled division.
2. Cell repair and cell death:- Normal cells, if damaged are sent for repair or they undergo apoptosis when they are old or get damaged. But cancer cells do not go into repair or apoptosis leading to the proliferation of damaged cells which in turn leads to production of damaged protein.
3. Metastasis:- As we know normal cells stick to each other at one location but cancer cells " float away" to locations nearby, through blood or lymph. As they arrive to new location they start to grow, forming new tumors.
4. Cell shape and size:- Cancer cells and Normal cells may look different in shape and size from each other. Cancer cells may look small or big in size as compared to normal cells. Their shape also changes from that of regular cells.

Organs in which cancer cells occurs also show irregular functions like if cancer is in hormone producing organ then it will either produce excess hormone or no hormone which will lead to abnormal functioning of body. Similarly due to Cancer of WBCs i.e. leukemia, the Number of WBCs (White Blood Cells) are increased many folds but still they do not function properly leading to person more prone to infections.

It is very important to study about cancer cells So that one should know the nature of cancer cells and how they are different from other normal cells. In order to kill cancer cells it must be known how to distinguish between cancer and normal cells.