It is important for cells to regulate the expression of oncogenes and tumor suppressor genes to prevent the development of malignancies. Oncogenes are genes that when mutated or overexpressed, promote cell proliferation and tumor formation. In contrast, tumor suppressor genes normally inhibit cell growth and division, preventing the development of cancer. By regulating the expression of both oncogenes and tumor suppressor genes, it ensures that cell growth does not lead to uncontrolled proliferation. Tumor suppressor genes are involved in repairing DNA damage, and inducing cell death when necessary. Dysregulation of these genes can result in genomic instability due to the accumulation of mutations.