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Pharmacogenomic profiling of the PI3K/PTEN pathway in sporadic breast cancer

Issar Nassiri1, Mehri Faghihi2, Manoochehr Tavassoli1

  • 1Division of Genetics, Dept. of Biology, Faculty of Science, Medical University of Isfahan, Isfahan, Iran.

Iranian Biomedical Journal
|May 28, 2009
PubMed
Abstract

Insights

Genetic variations in the PTEN gene were investigated in Iranian breast cancer patients. Mutations in PTEN were identified in 7% of samples, highlighting its role in breast cancer development and potential therapeutic strategies.

Area of Science:

  • Oncology
  • Genetics
  • Pharmacogenomics

Background:

  • Breast cancer is a prevalent global cancer in women.
  • Pharmacogenomics aids in tailoring chemotherapy based on individual genetic profiles.
  • PTEN gene anomalies are implicated in phosphatidylinositol 3 kinase pathways in breast cancer.

Purpose of the Study:

  • To investigate the role of the tumor suppressor PTEN/MMAC1 gene in Isfahanian breast cancer patients.
  • To identify and characterize PTEN gene mutations in breast cancer.
  • To understand the implications of PTEN mutations for targeted therapies.

Main Methods:

  • PTEN gene mutations were analyzed in 72 breast cancer tumors.
  • Techniques included polymerase chain reaction, single strand conformation polymorphism, Heteroduplex mobility assay, and DNA sequencing.
  • Detection and characterization of mutations were performed.

Main Results:

  • Nucleotide substitutions in the PTEN gene were detected in 7% (5/72) of breast cancer samples.
  • Specific mutations identified include p.D92N, p.C105W, p.D107N, p.A121P, and p.R130Q.
  • A novel mutation, p.D107N, was identified in this study.

Conclusions:

  • Loss of PTEN function, through mutation or reduced expression, occurs in nearly half of sporadic breast tumors.
  • PTEN mutations are significant for developing novel therapeutics targeting breast cancer.
  • Understanding PTEN's role is crucial for optimizing the biological efficacy of cancer treatments.
Keywords:
Breast cancerPharmacogenomicRapamycinSomatic mutation

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