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


METHODS
In vitro study.


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


METHODS
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.


RESULTS
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.


CONCLUSIONS
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.
Heiduschka
Gregor
G
Department of Otorhinolaryngology-Head and Neck Surgery, Medical University of Vienna, Vienna, Austria.
Erovic
Boban M
BM
Vormittag
Laurenz
L
Skoda
Christiane
C
Martinek
Helga
H
Brunner
Markus
M
Ehrenberger
Klaus
K
Thurnher
Dietmar
D
D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology; D002452:Cell Count; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000187:drug effects / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D006258:Head and Neck Neoplasms / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology; D006801:Humans; D006888:Hydroxycholesterols / Q000494:pharmacology*; D007150:Immunohistochemistry
D006888:Hydroxycholesterols; C011724:cholest-5-en-3 beta,7 alpha-diol; D051546:Cyclooxygenase 2