What is the role of an oncogene?

An oncogene is a type of gene that has the potential to cause cancer when it becomes mutated or expressed at high levels. The primary role of an oncogene is to promote uncontrolled cell growth and division, which can lead to the development of tumors. When an oncogene is overactive due to mutations or amplification, it can function constantly to stimulate the cell cycle, bypassing the normal regulatory mechanisms that keep cell proliferation in check.

In normal cells, proto-oncogenes help regulate cell division and growth. However, when these genes become oncogenes, they can drive the transformation of normal cells into cancerous cells by promoting excessive cell proliferation, inhibiting apoptosis (programmed cell death), or enhancing the ability of cells to invade other tissues. This misregulation is a key factor in tumorigenesis.

The other roles represented in the choices do not align with the function of oncogenes. For instance, while apoptosis is a normal process that removes damaged or unnecessary cells, oncogenes typically act against this process when over-activated. DNA repair is specifically associated with tumor suppressor genes, which actually work to prevent uncontrolled growth. Regulation of the cell cycle can involve both oncogenes and tumor suppressor genes, but oncogen