During malignant transformation, cells undergo several critical changes:
Loss of Cell Cycle Control: Normal cells have tightly regulated cell cycles. Cancer cells often have mutations in genes that control cell division, such as the p53 or RB1 genes. Apoptosis Evasion: Cancer cells evade programmed cell death, which allows them to survive longer than normal cells. Mutations in the BCL-2 family of genes are often involved in this process. Increased Proliferation: Cancer cells often exhibit increased proliferation due to mutations in oncogenes like RAS or MYC. Angiogenesis: Tumors stimulate the formation of new blood vessels to supply nutrients and oxygen, often through the secretion of growth factors like VEGF. Invasion and Metastasis: Cancer cells lose their adherence properties and gain the ability to invade surrounding tissues and spread to distant sites.
