Neuregulin-1-Mediated Autocrine Signaling Underlies Sensitivity to HER2 Kinase Inhibitors in a Subset of Human Cancers

SummaryHER2 kinase inhibitors, such as lapatinib, have demonstrated clinical efficacy in HER2-amplified breast cancers. By profiling nearly 700 human cancer cell lines, we identified a subset of non-HER2 amplified cancer cells with striking sensitivity to HER2 kinase inhibition—particularly from head and neck tumors. These cells were found to depend on a neuregulin-1 (NRG1)-mediated autocrine loop driving HER3 activation, which can be disrupted by lapatinib. Elevated NRG1 expression and activated HER3 are strongly associated with lapatinib sensitivity in vitro, and these biomarkers were enriched in a subset of primary head and neck cancer samples. The findings suggest that patients with NRG1-driven tumors lacking HER2 amplification may derive significant clinical benefit from HER2:HER3-directed therapies.

► A tumor cell line screen revealed non-HER2 amplified, lapatinib-sensitive cell lines
► Lapatinib-sensitive cell lines exhibit NRG1-driven autocrine survival signaling
► Elevated NRG1 expression and HER3 activation were observed in head and neck tumors
► NRG1-driven cancers may benefit from HER2:HER3-targeted therapies