Additive antitumor effects of celecoxib and simvastatin on head and neck squamous cell carcinoma in vitro.

Lipid-lowering statins as well as non-steroidal anti-inflammatory drugs (NSAIDs) have been reported to possess cancer-protective effects in many epidemiologic cohort studies. However, the underlying mechanisms of these findings are mostly unknown. To evaluate possible additive antitumor effects of statins and NSAIDs in vitro, PJ-41 and HLaC78 head and neck squamous cell carcinoma cells (HNSCC) were treated with 40 µM celecoxib, 50 µM simvastatin or a combination of both. Analysis of tumor viability, proliferation, apoptosis, cell cycle changes and secretion of interleukin-6 (IL-6) and interleukin-8 (IL-8) was conducted via MTT assay, Annexin V-propidium iodide test, cell cycle analysis, colony assay and enzyme-linked immunosorbent assay (ELISA). Celecoxib and simvastatin alone as well as a combined treatment showed a significant reduction in tumor cell viability, proliferation and secretion of IL-6 and IL-8 compared to the control group. The combined treatment even proved to have significantly greater effects. We postulate that simvastatin and celecoxib have additive antitumor effects on HNSCC in vitro, which warrants further investigation.