Anti-leukemic activities of alcoholic extracts of two traditional Indian medicinal plants.

The present work aimed to investigate the anticancer in vitro activity of two plants commonly used in traditional Indian medicine: Zingiber officinale Roscoe and Nerium oleander L. The extracts of these plants were tested in vitro on several human leukemic cell lines, K562, THP-1, MOLT-4 and Jurkat. Cell growth inhibition was observed for both plant extracts with 50% inhibitory concentration (IC50) values ranging between 1 and 28 μg/mL using SRB (sulphorodamine B) and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assays. Enhanced cell growth inhibition was observed when the extracts were combined with imatinib. Exposed cells showed cell cycle arrest, DNA damage and cytochrome c release, indicating that the mechanism of cytotoxicity could be via mitochondrial mediated apoptotic pathways. Combination of the extracts of these plants with standard cancer treatment may be a way of enhancing responses. Clinical studies in patients with chronic myeloid leukemia are planned at our center.