The present work tested organic solvents to prepare an extract with anticancer properties from a polyherbal mixture containing Nigella sativa (seeds), Hemidesmus indicus (roots) and Smilax glabra (rhizomes). We evaluate anticancer effects in non-small-cell lung cancer cells (NCI-H292), and discuss optimization for pharmaceutical use in the context of efficacy, yield and toxicity.Using different organic solvents, six extracts were prepared from the polyherbal mixture. Based on the cytotoxic effects of these extracts on NCI-H292 cells and normal lung cells (MRC-5), as evaluated by the sulphorhodamine B assay, the total ethyl acetate (T-EA) extract was selected for further analysis. The possible anticancer mechanisms were assessed by evaluating the extract's effects on apoptosis (through fluorescent microscopic analysis, DNA fragmentation analysis, caspase 3/7 assay and analysis of expression levels of apoptosis-related genes p53, Bax, survivin, Hsp70 and Hsp90), colony formation and antioxidant activity.The extract had cytotoxic effects against NCI-H292 cells in a time- and dose-dependent manner. Significant antioxidant activity and inhibition of colony formation were also observed. The expression level of caspase 3/7 significantly (P < 0.001) increased in NCI-H292 cells treated with 50 μg/mL of the extract. The same dosage led to a significant increase in expression levels of Bax and p53 (P < 0.05 and P < 0.01 respectively), accompanied by a significant decrease (P < 0.0001) in survivin, Hsp 70 and Hsp 90.T-EA extract of the above polyherbal mixture has cytotoxicity against NCI-H292 cells via induction of apoptosis, antioxidant effects and inhibition of colony formation.
