Dose-response curve of E. longifolia crude extract and Tamoxifen against malignant cells (HM3KO, Hela, HepG2 and CaOV3) and non-malignant cells (CCD11114sk and Chang's liver). E. longifolia crude extract showed a higher toxicity towards HepG2 cells compared to the other cell lines used in the experiment. Non-malignant cells, Chang's Liver and CCD11114sk were not significantly affected by the crude extract and no IC50 was evident (a). Tamoxifen showed a cytotoxic effects on all of the cell lines used in the experiment including non-malignant cells, Chang's liver and CCD11114sk (b). The values of graph represent mean ± S.D of three independent experiments. P < 0.05.