Based on what you read in this chapter, Why do most cancers require the mutation of multiple genes?

Key Concepts

Multistep Carcinogenesis

Multistep carcinogenesis is the process by which cancer develops through a series of genetic mutations over time. Initially, a single mutation may give a cell a growth advantage, but subsequent mutations are often required to enable further growth, invasion, and metastasis. This concept highlights that cancer is not caused by a single genetic change but rather a cumulative effect of multiple alterations in various genes.

Oncogenes and Tumor Suppressor Genes

Oncogenes and tumor suppressor genes play crucial roles in regulating cell growth and division. Oncogenes, when mutated, can promote uncontrolled cell proliferation, while tumor suppressor genes normally inhibit cell division and promote apoptosis. The interplay between these two types of genes is essential in cancer development, as mutations in both can lead to the transformation of normal cells into cancerous ones.

Genetic Instability

Genetic instability refers to an increased tendency of the genome to acquire mutations, which can result from defects in DNA repair mechanisms. This instability can lead to a higher frequency of mutations in critical genes, contributing to cancer progression. As cells divide, the accumulation of these mutations can create a diverse population of cancer cells, each with different characteristics and behaviors.