How can the role of epigenetics in cancer be reconciled with the idea that cancer is caused by the accumulation of genetic mutations in tumor-suppressor genes and proto-oncogenes?

Key Concepts

Epigenetics

Epigenetics refers to the study of changes in gene expression that do not involve alterations to the underlying DNA sequence. These changes can be influenced by environmental factors and can affect how genes are turned on or off. In cancer, epigenetic modifications can lead to the silencing of tumor-suppressor genes or the activation of oncogenes, contributing to tumor development.

Genetic Mutations

Genetic mutations are permanent alterations in the DNA sequence that can lead to changes in protein function. In cancer, mutations often occur in tumor-suppressor genes, which normally prevent uncontrolled cell growth, or in proto-oncogenes, which promote cell division. The accumulation of these mutations is a key factor in the progression of cancer, leading to the transformation of normal cells into malignant ones.

Tumor-Suppressor Genes and Proto-Oncogenes

Tumor-suppressor genes are responsible for regulating cell division and preventing tumor formation, while proto-oncogenes promote cell growth and division. When mutations occur in these genes, they can disrupt normal cellular functions, leading to cancer. Understanding the interplay between genetic mutations in these genes and epigenetic modifications is crucial for comprehending the multifaceted nature of cancer development.