Antiproliferative effects of pereskiopsis diguetii, caralluma speciosa and euphorbia ritchiei hydroalcoholic extract

Abstract

To date, cancers remain to be global health problem. The toxicity and the emergence of chemotherapy resistance of currently prescribed anticancer agents highlight the need for the discovery and the development of novel anticancer drugs. The previous successes in the discovery of anticancer agents and other biologically active compounds from diverse types of flora support the value of plants as natural resources for the screening of novel drugs. However, the pharmacological data of succulent plants are largely limited. Objectives: Here, we screened hydroalcoholic extracts of selected succulent plants for potential anticancer activities against four cancer cell lines including colorectal cancer cell line HT29, hepatocellular carcinoma cell line HepG2, head-and-neck cancer cell line HN22, and cervical cancer cell line HeLa. Materials and Methods: Crude extracts were obtained from fresh specimens using 95% ethanol as solvent, concentrated using a rotary evaporator, and dissolved in dimethyl sulfoxide. 50–500 mg/ml of extracts were first evaluated for cytotoxicity through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay at 48 or 72 h. The extracts showing cytotoxicity were further examined through flow cytometry for cell cycle distribution. Results: Pereskiopsis diguetii (F.A.C. Weber) Britton and Rose, a member of Cactaceae family, exhibited cytotoxic effects against HT29, HepG2, and HN22. Caralluma speciosa (N.E.Br.) N.E.Br., a member of Apocynaceae family, exhibited cytotoxic activities toward HT29 and HN22 cells. Euphorbia ritchiei (P. R. O. Bally) Bruyns exhibited cytotoxic effects against HepG2, HN22, and HeLa. Flow cytometry analysis revealed that these extracts altered cell cycle profile of the majority of the susceptible cancer cell lines, suggesting that these extracts likely exhibited antiproliferative or pro-apoptotic activities. Conclusion: Together, our results pinpointed these succulents as potential candidates for further investigations which may lead to the discovery of novel anticancer agents.