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Correlating phosphatidylinositol 3-kinase inhibitor efficacy with signaling pathway status: in silico and biological

Shingo Dan1, Mutsumi Okamura, Mariko Seki

  • 1Division of Molecular Pharmacology, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo, Japan.

Cancer Research
|June 10, 2010
PubMed

Insights

Predicting cancer drug efficacy is possible by analyzing pathway member status. Phospho-Akt levels and KRAS/BRAF mutations correlate with phosphatidylinositol 3-kinase (PI3K) inhibitor effectiveness, aiding biomarker discovery.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • The phosphatidylinositol 3-kinase (PI3K) pathway is frequently hyperactivated in human cancers.
  • Targeting the PI3K pathway with inhibitors is a promising therapeutic strategy currently in clinical trials.

Purpose of the Study:

  • To investigate whether the efficacy of PI3K pathway inhibitors can be predicted by the activation status of pathway components.
  • To identify reliable predictive biomarkers for PI3K inhibitor response in cancer.

Main Methods:

  • Examined mutation, expression, and phosphorylation of PI3K and Ras pathway members in 39 human cancer cell lines (JFCR39).
  • Assessed in vitro efficacy of 25 PI3K inhibitors and conventional drugs.
  • Constructed an integrated database (JFCR39-DB) of pathway status and drug efficacies.
  • Performed in silico analysis to correlate pathway member status with drug efficacy, validated in vivo using tumor xenografts.

Main Results:

  • Phospho-Akt levels strongly correlated with PI3K inhibitor efficacy.
  • KRAS/BRAF mutations correlated with PI3K inhibitor inefficacy.
  • PIK3CA mutations and PTEN loss did not show significant correlations with efficacy.
  • Correlations were validated in vivo, confirming biomarker potential.

Conclusions:

  • The JFCR39-DB database is a valuable tool for identifying predictive biomarkers of PI3K inhibitor efficacy.
  • Phospho-Akt and KRAS/BRAF mutations serve as potential predictive biomarkers for PI3K pathway-targeted therapies.
  • Understanding pathway activation status is crucial for optimizing cancer treatment strategies.

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