title: Evaluating the cytotoxic effects of the water extracts of four anticancer herbs against human malignant melanoma cells.
abstract: Malignant melanoma (MM) is the most dangerous type of skin cancer, killing more than 1,100 people each year in Canada. Prognosis for late stage and recurrent MM is extremely poor due to insensitivity to chemotherapy drugs, and thus many patients seek complementary and alternative medicines. In this study, we examined four commonly used anticancer herbs in traditional Chinese medicine,Hedyotis diffusa,Scutellaria barbata,Lobelia chinensis, andSolanum nigrum, for their in vitro antitumor effects toward human MM cell line A-375. The crude water extract ofS. nigrum(1 g of dry herb in 100 mL water) and its 2-fold dilution caused 52.8%±13.0% and 17.3%±2.7% cytotoxicity in A-375 cells, respectively (P<0.01). The crude water extract ofH. diffusacaused 11.1%±12.4% cytotoxicity in A-375 cells with no statistical significance (P>0.05). Higher concentrated formulation might be needed forH. diffusato exert its cytotoxic effect against A-375 cells. No cytotoxicity was observed in A-375 cells treated with crude water extract ofS. barbataandL. chinensis. Further high performance liquid chromatography-tandem mass spectroscopy analysis of the herbal extracts implicated thatS. nigrumandH. diffusamight have adopted the same bioactive components for their cytotoxic effects in spite of belonging to two different plant families. We also showed that the crude water extract ofS. nigrumreduced intracellular reactive oxygen species generation in A-375 cells, which may lead to a cytostatic effect. Furthermore, synergistic effect was achieved when crude water extract ofS. nigrumwas coadministered with temozolomide, a chemotherapy drug for skin cancer.
authors.affiliation: Drug Discovery and Development Research Group, College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK; Department of Biomedical and Molecular Sciences, Queen's University, Cancer Biology & Genetics Division, Queen's Cancer Research Institute, Kingston, ON, Canada.
authors.forename: Binbing
authors.initials: B
authors.lastname: Ling
authors.affiliation: Drug Discovery and Development Research Group, College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK.
authors.forename: Deborah
authors.initials: D
authors.lastname: Michel
authors.affiliation: Drug Discovery and Development Research Group, College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK.
authors.forename: Meena Kishore
authors.initials: MK
authors.lastname: Sakharkar
authors.affiliation: Drug Discovery and Development Research Group, College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, SK.
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
mesh_terms: D018906:Antineoplastic Agents, Alkylating / Q000494:pharmacology; D000972:Antineoplastic Agents, Phytogenic / Q000302:isolation & purification / Q000494:pharmacology*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology; D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology; D045744:Cell Line, Tumor; D002851:Chromatography, High Pressure Liquid; D003606:Dacarbazine / Q000031:analogs & derivatives / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D032064:Hedyotis / Q000737:chemistry; D006801:Humans; D029746:Lobelia / Q000737:chemistry; D008545:Melanoma / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008517:Phytotherapy; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D010946:Plants, Medicinal; D017382:Reactive Oxygen Species / Q000378:metabolism; D031363:Scutellaria / Q000737:chemistry; D012878:Skin Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D032324:Solanum nigrum / Q000737:chemistry; D012997:Solvents / Q000737:chemistry*; D053719:Tandem Mass Spectrometry; D000077204:Temozolomide; D014867:Water / Q000737:chemistry*
chemical_list: D018906:Antineoplastic Agents, Alkylating; D000972:Antineoplastic Agents, Phytogenic; D000975:Antioxidants; D010936:Plant Extracts; D017382:Reactive Oxygen Species; D012997:Solvents; D014867:Water; D003606:Dacarbazine; D000077204:Temozolomide
keywords: HPLC-MS/MS; cytotoxicity; herbal extract; malignant melanoma; reactive oxygen species