Strategic targeting of the PI3K-NFκB axis in cisplatin-resistant NSCLC

Susan Heavey1, Peter Godwin1, Anne-Marie Baird2

  • 1Thoracic Oncology Research Group; Institute of Molecular Medicine; Trinity Centre for Health Sciences; St. James's Hospital; Dublin, Ireland.

Insights

Nuclear factor-kappa B (NFκB) inhibition shows promise for overcoming chemoresistance in non-small cell lung cancer (NSCLC). Targeting NFκB, not PI3K-mTOR, significantly enhanced treatment effects in cisplatin-resistant NSCLC cells.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • Chemoresistance in non-small cell lung cancer (NSCLC) significantly limits treatment efficacy, contributing to poor patient survival rates.
  • Increased phosphoinositide 3-kinase (PI3K) signaling is linked to aggressive NSCLC and worse prognosis.
  • Understanding resistance mechanisms is crucial for developing effective therapeutic strategies.

Purpose of the Study:

  • To investigate the therapeutic potential of targeting the PI3K-NFκB axis in cisplatin-resistant NSCLC.
  • To identify vulnerabilities in chemoresistant NSCLC cells by comparing gene expression profiles.
  • To evaluate the efficacy of dual PI3K-mTOR inhibitor (GDC-0980) and NFκB translocation inhibitor (DHMEQ) in resistant cells.

Main Methods:

  • Generated cisplatin-resistant NSCLC cell lines through prolonged drug exposure.
  • Compared gene expression of PI3K and NFκB pathway-related genes using gene arrays, qRT-PCR, DNA sequencing, western blot, and immunofluorescence.
  • Assessed inhibitor effects on cell proliferation and viability using BrdU assay and multiparameter viability assay.

Main Results:

  • NFKBIA was overexpressed 12-fold in cisplatin-resistant cells without mutations in key exons.
  • Corresponding overexpression of IκBα was observed in resistant cells.
  • DHMEQ treatment significantly enhanced anti-proliferative and viability effects in resistant cells, whereas GDC-0980 showed no significant difference compared to parent cells.

Conclusions:

  • NFκB pathway dysregulation, specifically NFKBIA overexpression, is implicated in cisplatin resistance in NSCLC.
  • Targeted inhibition of NFκB translocation with DHMEQ is a more promising strategy than PI3K-mTOR inhibition for overcoming chemoresistance in NSCLC.
  • Further research into NFκB as a therapeutic target could improve treatment outcomes for chemoresistant NSCLC.