In vitro anticancer activity of PI3K alpha selective inhibitor BYL719 in head and neck cancer

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• Head and neck cancers (HNC) are a significant global health concern.
• Dysregulation of the PI3K/AKT/mTOR pathway is implicated in HNC development and progression.
• Targeting PI3K offers a potential therapeutic strategy for HNC.

Purpose of the Study:

• To evaluate the antiproliferative activity of BYL719, a PI3K p110α inhibitor, in HNC cell lines.
• To assess the efficacy of BYL719 as a single agent and in combination with dacomitinib, an EGFR inhibitor.
• To investigate the molecular mechanisms underlying BYL719's effects in HNC.

Main Methods:

• Six human HNC cell lines were utilized, including two PIK3CA-mutant and four PIK3CA wild-type lines.
• Cell viability and proliferation were assessed following treatment with BYL719 and dacomitinib.
• Cell cycle distribution and apoptosis were analyzed using flow cytometry.
• Western blotting was employed to examine the expression of key signaling proteins (p-mTOR, p-AKT, p-S6).

Main Results:

• PIK3CA-mutant HNC cell lines demonstrated greater sensitivity to BYL719 compared to PIK3CA wild-type lines.
• BYL719 treatment led to dose-dependent G0/G1 cell cycle arrest and increased apoptosis.
• BYL719 effectively downregulated downstream signaling pathways, evidenced by reduced p-mTOR, p-AKT, and p-S6 levels.
• The combination therapy's efficacy requires further investigation.

Conclusions:

• BYL719 exhibits significant antiproliferative effects in HNC cell lines, particularly those with PIK3CA mutations.
• BYL719 induces cell cycle arrest and apoptosis, supporting its potential as a targeted therapy for HNC.
• BYL719, as a PI3K alpha selective blocker, holds promise for HNC treatment, either alone or combined with other agents like dacomitinib.