These recent findings indicate that potential etiological causes result in inducing genetic alterations in cells. In tumorigenesis, three types of genes are involved. they are:
1. Proto-oncogene: These are normal genes, but whenever they undergo any mutation or their expression is increased, they develop into an oncogene, hence converting the normal cell into a malignant type as well as that With uncontrolled proliferation of a particular type of cell. Oncogenes show activation, which predicts disease. One group of proto-oncogenes becomes disorganized when mutated and sends signals for uncontrolled division of cells while the other group of proto-oncogenes controls programmed death or apoptosis. Ras, Wnt, Myk, Erk, Trk are some important proto-oncogenes. 2. Onco-suppressor genes: They are actually onco-ducking genes or tumor suppressing genes that can induce apoptosis or programmed death. This is done regularly within the cell. Disruption of these genes by mutation has been implicated in preventing programmed cell death of cancer cells as well as senescent cells and thus causing them to grow uncontrolled. There are three types of gene onco-suppressors. Care-taker genes then have a function within the cell, ensuring DNA repair, genomic stability and subsequently, when mutated, allowing mutations to accumulate. Gatekeeper genes directly regulate cell growth by eliciting checkpoint events through inhibition of cell cycle progression or induction of apoptosis. Finally, land pattern genes regulate development by contributing to the surrounding environment. When mutated, it can create an environment that promotes uncontrolled proliferation. Tumor suppressor genes or the proteins they encode may exert suppressive effects on cell cycle regulation or promote apoptosis or both. 3. DNA Repair Genes: Effective DNA repair is the backbone of cancer-free survival. These are a group of genes that are responsible for the repair of DNA damage, caused either by endogenous sources such as free radicals or exogenous sources such as UV radiation. When too many DNA damages and/or mutations accumulate in a cell, the cell loses the ability to repair DNA and may undergo one of three possible fates: 1. Senescence 2. Apoptosis 3. Dysregulation Cell division, which can lead to tumor formation, which can be cancer. By alteration or mutation of any DNA repair gene, inactivation of other tumor suppressor genes will occur, and activation of oncogenes will become possible. The DNA repair ability of a cell is critical to the normal function of that organism.