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The PIK3CA gene is mutated with high frequency in human breast cancers

Kurtis E Bachman1, Pedram Argani, Yardena Samuels

  • 1The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Department of Oncology, Baltimore, Maryland 21231, USA. kbachman1@yahoo.com

Cancer Biology & Therapy
|July 16, 2004
PubMed

Insights

Somatic mutations in the PIK3CA gene, a key regulator of cell growth, are common in breast cancer. These findings highlight PIK3CA as a significant oncogene in epithelial carcinogenesis.

Area of Science:

  • Oncology
  • Molecular Biology
  • Genetics

Background:

  • Phosphatidylinositol 3-kinases (PI3Ks) regulate fundamental cellular processes like growth and proliferation.
  • Somatic mutations in PIK3CA, encoding the p110alpha subunit of PI3K, have been implicated in various human cancers.

Purpose of the Study:

  • To investigate the frequency and location of PIK3CA somatic mutations in breast cancer specimens.
  • To determine the role of PIK3CA mutations in the development of epithelial cancers, specifically breast cancer.

Main Methods:

  • Analysis of DNA from 53 breast cancer samples to identify somatic mutations.
  • Sequencing of the PIK3CA gene, with a focus on the kinase domain.

Main Results:

  • Somatic mutations in PIK3CA were identified in 13 out of 53 breast cancers (25%).
  • The majority of these PIK3CA mutations were concentrated within the kinase domain of the gene.

Conclusions:

  • PIK3CA is the most frequently mutated oncogene identified in this cohort of breast cancers.
  • The high mutation rate supports a critical role for PIK3CA in the pathogenesis of epithelial cancers, including breast cancer.

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