Pharmacological profiling of kinase dependency in cell lines across triple-negative breast cancer subtypes

Lauren S Fink1, Alexander Beatty1, Karthik Devarajan2

  • 1Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania.

Insights

Triple-negative breast cancer (TNBC) subtypes do not predict kinase inhibitor sensitivity. Instead, PTEN mutation status and epidermal growth factor signaling dependence identify TNBCs sensitive to specific kinase inhibitors, guiding targeted therapy development.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • Triple-negative breast cancer (TNBC) lacks targeted therapies due to heterogeneity and absence of common drivers.
  • Kinase signaling is implicated in TNBC, but effective therapeutic targets remain elusive.
  • Gene expression-based TNBC subtypes were proposed to predict sensitivity to kinase inhibitors.

Purpose of the Study:

  • To evaluate the correlation between TNBC subtypes and sensitivity to kinase inhibitors.
  • To identify alternative predictors of kinase inhibitor response in TNBC.
  • To discover novel kinase inhibitors with selective toxicity for TNBC subsets.

Main Methods:

  • Screening of a diverse panel of TNBC cell lines representing six subtypes against numerous small molecule kinase inhibitors.
  • Unsupervised clustering of cell lines based on growth inhibition data.
  • Correlation analysis between TNBC subtypes, gene expression, mutation status (e.g., PTEN), and response to kinase inhibition.

Main Results:

  • TNBC subtype did not correlate with sensitivity to kinase inhibitors.
  • Unsupervised clustering revealed TNBC cell lines segregated based on dependence on epidermal growth factor signaling and PTEN mutation status.
  • Specific kinase inhibitors demonstrated selective toxicity against TNBC groups defined by these features.
  • Diverse sensitivity to kinase inhibition was observed across TNBC cell lines, reflecting disease heterogeneity.

Conclusions:

  • Gene expression-based TNBC subtypes are poor predictors of kinase inhibitor response.
  • PTEN mutation status and signaling pathway dependence are more effective biomarkers for predicting sensitivity to specific kinase inhibitors in TNBC subsets.
  • Targeted therapy development for TNBC should consider mutation status and signaling dependencies over gene expression subtypes.