| Cancer |
| What is Cancer? |
| Because there is mutation in the DNA of a cell, this phenomenon causes cell to proliferate uncontrollably. Another reason could be, environmental factors induces stress to the DNA of one's. These factors like heat, radiation etc. causes the DNA to mutate. Hence, causing cell to once again proliferate uncontrollably. |
| How come epithelial cells are more prone to cancer? |
| So far, the reason is still inconclusive. But, one thing is for sure, is that epithelial cells proliferate more compared too non-epithelial cells; like the muscle cells, nervous tissue etc. There are also other factors contributing to this phenomenon. One of it is, due to the nature of epithelial cells - needing to constantly proliferate, there is a lack of cell cycle control mechanisms. |
| What are the mechanisms? |
| Cell cycle is controlled by the following factors: Cyclin - proteins involved in cell cycle progression, which form a complex with your CDK to activate protein kinase function. CDK (cyclin dependant kinase) - a group of protein kinase involved in the relgulation of cell cycle, binding to cycling forming a complex. CDKi (cycling dependent inhibitor) - Binds to cyclin/cdk complex and inhibits the activity. there are about 7 types of CDKi in homosapiens, grouped into 3 categories; Cip, Kip & INK4. |
| How mechanism affects epithelial cells proliferation? |
| Epithelial cells should have cyclin/cdk complex and CDKi for cell proliferation and regulation. But why the proness to cancer? It is because epithelial cells are constantly proliferating, this makes the cell more susceptible to mutation which in turn leading to cancer. Because of this, the CDKi in epithelial cells are naturally lower (because the cells are always proliferating) compared to other cells. That is why, when the epithelial cells undergo mutation or any sort of damage and starts to proliferate uncontrollably, since there is not enough CDKi to inhibit the unwanted growth of the cells. |
| Other factors that regulate cell proliferation. |
| Contact inhibition is another mechanism which regulates the cell proliferation. Normal cells should stop growing when there are no longer space to grow, this is due to the cell able to recognize it's surrounding. If a cell fails to respond to contact inhibition, it would cause them to just continue proliferating uncontrollably. An example would be, breast epithelial cells which fail to senesce are very prone to develop into aggressive breast cancer. |
| Credits: Dr Khair researcher (RP) Dr Chew Xuan Hui assistant researcher(RP) Dr Ashraf Ali senior editor (RP) Special thanks Dr Sanaul Chowdhury MD, PhD |
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| Dr Elaine researcher (RP) Dr Mei Yan researcher (RP) |
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