Safety of herbal medicine use during chemotherapy in patients with ovarian cancer: a ''bedside-to-bench'' approach

In this study, we explored herbal supplements used by patients during chemotherapy and test for herbdrug interactions and response of cancer cells to treatment. Patients with gynecological cancer referred to a complementary and integrative medicine (CIM) service were asked about their use of herbal medicine during chemotherapy. The leading five clinically relevant herbs selected for cytotoxicity analysis included the following: wheatgrass (Triticum aestivum), European mistletoe (Viscum album), ginger (Zingiber officinale), Ephedra (Ephedra campylopoda), and Oriental mistletoe (Viscum cruciatum). Cytotoxicity was examined using XTT assays in cisplatin-sensitive and resistant ovarian cancer cell lines (A2780, A2780CisR), and non-cancer kidney cells (HEK293). The effect of the selected herbs on carboplatin and paclitaxel cytotoxicity was tested as well. Pro-apoptotic effects were tested using Poly( ADP-ribose) polymerase (PARP) cleavage. Of 98 patients referred to the CIM service, 42 (42.9%) reported using/intending to use herbal products during chemotherapy. European mistletoe and ginger exhibited significant anti-cancer activity in cisplatin-sensitive and resistant ovarian cells. Wheatgrass and ephedra reduced cytotoxicity of carboplatin on cisplatinsensitive ovarian cancer cells, while ginger, European and Oriental mistletoe increased chemosensitivity in both cancer cell lines. Wheatgrass, European mistletoe, and ginger increased sensitivity to cisplatin-resistant cells treated with carboplatin and paclitaxel. No effect was observed with the addition of any of the herbs on noncancerous embryonic kidney cells (HEK-293). Herbal medicine use by patients with ovarian cancer may influence anti-cancer activity of chemotherapy. Integrative physicians can provide ''bedside-to-bench'' guidance on the safety of these products.