Inside "Cancer Genes":

@CancerQuest on Twitter:

Related to this page:

Test your knowledge on Cancer Genes

Topics you may also like:

BRCA Function

An Introduction to Tumor Suppressors

Was this page helpful? | What did you like most? How can we make it better?

CancerQuest > Introduction to Cancer Biology > Cancer Genes > An Introduction to Tumor Suppressors > Tumor Suppressors: BRCA Introduction

Tumor Suppressors: BRCA Introduction

The BRCA proteins have multiple functions. One important role is in the repair of DNA damage. They have also been implicated in the regulation of gene expression. The BRCA-1 gene is associated with the activation of another tumor suppressor, p53, and its target gene p21. BRCA proteins also interact with transcription factors and other transcription components to control the activity of several other genes.⁽¹⁾ When the BRCA genes are non-functional, DNA repair and gene regulation are compromised. The increase in DNA damage can lead to the generation of cells that accumulate mutations in key genes, leading to cancer cell formation. Cells lacking functional BRCA genes often suffer from chromosomal breaks, severe aneuploidy, and may contain too many centrosomes.  All of these defects interfere with normal cell division and cell function.

At the molecular level, the structure of the BRCA-1 and -2 genes provides an explanation for their susceptibility to mutation. They contain a very high proportion of repetitive DNA, which is rare in human genes. The repetitive DNA can lead to genomic instability and rearrangements. ⁽¹⁾

Several lines of work have demonstrated that loss of BRCA gene products is associated with the development of sporadic and inherited cancer.⁽¹⁾

References for this page:

1. Welcsh PL, King MC. "BRCA-1 and BRCA-2 and the Genetics of Breast and Ovarian Cancer." Human Molecular Genetics (2001). 10(7): 705-713. [http://hmg.oupjournals.org/cgi/content/full/10/7/705] [PUBMED]
2. Narod SA, Boyd J. "Current Understanding of Epidemiology and Clinical Implications of BRCA-1 and BRCA-2 Mutations for Ovarian Cancer." Current Opinion in Obstetrics and Gynecology (2002). 14: 19-26. [PUBMED]