7beta-hydroxycholesterol induces apoptosis and regulates cyclooxygenase 2 in head and neck squamous cell carcinoma

To determine whether treatment with 7beta-hydroxycholesterol (7beta-HC) would trigger cell death in head and neck squamous cell carcinoma (HNSCC) cell lines in a dose-dependent fashion.

In vitro study.

The study included HNSCC cell lines SCC9, SCC25, CAL27, and FaDu.

We treated HNSCC cell lines with increasing doses of 7beta-HC. Proliferation assays were performed to assess cell viability after treatment. Western blots were carried out to evaluate cyclooxygenase (COX)-1 and -2 expression levels.

Using proliferation assays and immunocytochemical analysis, we detected significant growth inhibition via apoptosis in 4 different HNSCC cell lines after treatment with 7beta-HC (P < .001). The 50% inhibitory concentration levels were between 13.19 and 20.79 micromol/L after 72 hours. Western analysis indicated that COX-2, but not COX-1, levels were suppressed after treatment.

Treatment with 7beta-HC resulted in suppression of HNSCC growth in vitro. Our data warrant further investigations for the potential use of 7beta-HC as a cytotoxic agent in head and neck cancer.