The process of multi-step carcinogenesis can be broadly divided into three stages: initiation, promotion, and progression.
Initiation Initiation is the first stage where a normal cell undergoes a genetic mutation. This mutation can be triggered by various factors such as exposure to carcinogens, radiation, or inherited genetic defects. The mutation usually involves critical genes like oncogenes and tumor suppressor genes.
Promotion During the promotion stage, the initiated cells are stimulated to proliferate. This stage is influenced by various promoters, which are agents that do not directly cause DNA damage but enhance cell proliferation. Chronic inflammation and hormonal imbalances often act as promoters.
Progression The final stage, progression, involves further genetic and epigenetic changes that lead to increased malignancy. This stage is characterized by the acquisition of invasive properties and the ability to metastasize, making the cancer more aggressive and harder to treat.
