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Oncogenic mutations of PIK3CA in human cancers

Yardena Samuels1, Victor E Velculescu

  • 1The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University Medical Institutions, Baltimore, Maryland 21231, USA.

Cell Cycle (Georgetown, Tex.)
|October 7, 2004
PubMed

Insights

Frequent mutations in the PIK3CA gene, encoding a key component of phosphatidylinositol 3-kinases (PI3Ks), were found in various human cancers. These PIK3CA gene alterations may serve as important diagnostic and therapeutic targets in oncology.

Area of Science:

  • Oncology
  • Molecular Biology
  • Genetics

Background:

  • Phosphatidylinositol 3-kinases (PI3Ks) are crucial regulators of cellular signaling pathways.
  • Genetic alterations in signaling molecules are common in human cancers.

Purpose of the Study:

  • To investigate genetic alterations in the PI3K gene family in human cancers.
  • To identify specific PI3K genes that are frequently mutated in various cancer types.

Main Methods:

  • Sequence analysis of the PI3K gene family.
  • Identification and characterization of mutations within the PIK3CA gene.

Main Results:

  • The PIK3CA gene, encoding the p110alpha catalytic subunit of PI3K, was frequently mutated in colon, breast, brain, and lung cancers.
  • Mutations predominantly clustered in the helical and catalytic domains of the PI3K protein.
  • At least one hotspot mutation was observed to enhance PI3K kinase activity.

Conclusions:

  • PIK3CA is one of the most highly mutated oncogenes identified in human cancers.
  • The frequent genetic alterations and functional impact of PIK3CA mutations suggest its role in cancer development.
  • PIK3CA represents a potential diagnostic and therapeutic target for various human cancers.

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