Question

So im confused about whether the 'oncogenes' are already in our body or the virus that invade our cells make them out of 'proto-oncogenes'. which one is it, or neither? also is it the same for 'tumor-suppressor(recessive oncogenes)' ? After i can figure out these, im wondering what are the importance of oncogene and tumor suppressor genes in cancer development? Thank you so much for your help!

Answer 1

Cellular differentiation is normally an orderly process that progresses from a state of immaturity to a state of maturity.Because all body cells are derived from the fertilised ova,all the cells have the potential to perform all body functions.As cells differentiate,this potential is repressed and the mature cell is capable of performing only specific functions.Two types of normal genes that can be affected by mutation are protooncogenes and tumor suppressor genes.Protooncogenes are normal cellular genes that are important regulators of normal cellular processes.Protooncogenes promote growth,whereas tumor suppressor genes,such as the gene for the tumor protein p53,suppress growth.Mutations that alter the the expression of protooncogenes can activate them to function as oncogenes.The protooncogene has been described as the genetic look that keeps the cell in its mature functioning state.When this lock is unlocked,as may occur through exposure to carcinogens or oncogenic viruses,genetic alterations and mutations occur.Tumor suppressor genes function to regulate cell growth.Mutations that alter tumor suppressor genes render them inactive ,resulting in a loss of their tumor-suppressing action.