Cytotoxicity of some Cameroonian spices and selected medicinal plant extracts

Ethnopharmacological relevance: Several medicinal plants and spices are used traditionally to treat cancers in Cameroon. Aim: Methanol extracts from thirty-four spices and plants, with related ethnobotanical use were investigated for their in vitro cytotoxicity on the human pancreatic cancer cell line MiaPaCa-2, leukemia CCRF-CEM cells and their multidrug resistant (MDR) subline CEM/ADR5000, and the normal human umbilical vein endothelial cells (HUVECs). In addition the anti-angiogenic properties of the most active extracts were investigated. Material and methods: The MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay was used for cytotoxic studies and the CAM-assay (chicken-chorioallantoic-membrane-assay) for anti-angiogenesis test. Results: The results of the cytotoxicity tests indicated that, when tested at 20 mu g/ml, extracts from Xylopia aethiopica, Echinops giganteus, Imperata cylindrica. Dorstenia psilirus and Piper capense were able to inhibit more that 50% the proliferation of the three tested cancer cells (MiaPaCa-2, CEM/ADR5000 CCRF-CEM). The lowest IC50 values of 6.86 mu g/ml on MiaPaCa-2 and 3.91 mu g/ml on CCRF-CEM cells were obtained with X. aethiopica, while the corresponding value of 6.56 mu g/ml was obtained with P. capense on CEM/ADR5000 cells. Against leukemia cells, no cross-resistance was observed with I. cylindrica, P. capense and Zinziber officinalis. Extracts from D. psilirus and E. giganteus were able to inhibit angiogenesis by more than 50% in quail embryo. Conclusion: The overall results of the present study provide supportive data on the use of some Cameroonian plants for cancer treatment. (C) 2011 Elsevier Ireland Ltd. All rights reserved.