YAP1 Gene Amplification is a Marker for Cetuximab Resistance in Head and Neck Cancer
(English)Manuscript (preprint) (Other academic)
The epidermal growth factor receptor (EGFR) is commonly overexpressed in head and neck squamous cell carcinomas (HNSCC). The monoclonal antibody cetuximab (Erbitux®) inhibits its signaling and has been approved for treatment of HNSCC. However, since many patients do not benefit from cetuximab treatment, predictive biomarkers of cetuximab response are required. The present study aims at finding novel markers of cetuximab resistance.
The intrinsic cetuximab sensitivity of 35 HNSCC cell lines was determined, and revealed a great variation in the response between cell lines. Five cell lines (14%) were cetuximab sensitive, and 12 (34%) were resistant. Interestingly, two cell lines proliferated after cetuximab treatment.
10 cell lines (five cetuximab sensitive and five cetuximab resistant) were selected for gene copy number array analysis on the Affymetrix SNP 6.0 platform. 39 protein coding genes were amplified in cetuximab resistant cells and normal in sensitive cells, all present on genomic regions 11q22.1 or 5p13-15. Five genes were selected for quantitative PCR verification, namely, YAP1 and TRPC6 (11q22.1) and PDCD6, TPPP, and PTGER4 (5p13-15). An extended panel of totally 10 cetuximab resistant and 10 sensitive cell lines verified that YAP1 amplified cells are cetuximab resistant.
YAP1 gene amplification was highly correlated to the YAP1 mRNA expression, which was significantly higher in cetuximab resistant cells than in sensitive. YAP1 downregulation resulted in increased cetuximab sensitivity in one of two cetuximab resistant cell lines investigated and growth inhibition in another. We conclude that YAP1 is a marker for cetuximab resistance in head and neck cancer.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-76151OAI: oai:DiVA.org:liu-76151DiVA: diva2:512754