Molecular Mechanisms of Oncogenesis

Oncogenesis is the process of transformation of normal cells into malignant cells. It is often initiated by a variety of exogenous environmental and lifestyle variables but can also be due to wide range of endogenous genetic, metabolic, and molecular elements. Proto-oncogenes, tumor-suppressor genes, and other genes that directly or indirectly regulate cell division, metabolism, genome integrity, and cell death are mutated through the complicated multistep molecular events that lead to oncogenesis. The abilities of cells to produce their own mitogenic signals, reject growth-inhibitory signals, dodge apoptosis, acquire vasculature, and multiply without bounds are a few characteristics of cancer cells. Such cellular mechanisms involved in oncogenesis and their molecular mechanisms have been discussed in this chapter.