Enhanced cytotoxicity and apoptosis by thymoquinone in combination with zoledronic acid in hormone- and drug-resistant prostate cancer cell lines.

Purpose: Thymoquinone (TQ), an active ingredient of black seed oil (Nigella Sativa), has been shown to possess cytotoxic activity against a variety of cancer cell lines. Our purpose was to investigate if the cytotoxic and apoptotic effect of zoledronic acid (ZA) can be enhanced by the addition of the TQ in hormone- and drug-refractory prostate cancer cells PC-3 and DU-145.

Methods: XTT cell proliferation assay was used to assess cytotoxicity; DNA fragmentation and caspase 3/7 activity were also measured.