Cytotoxicity effects of Citrullus colocynthis on Hep2 and L929 cell lines

In this study, we investigated in vitro anti-tumoral effects of whole extract from bitter melon on human caucasian larynx carcinoma cell line (Hep2) and normal mouse fibroblast cell line (L929) by MTT assay. Hep2 and L929 cell lines were maintained in RPMI-1640 culture medium. Bitter melon extract was prepared by 75% ethanol. The number of 5x104 cell/ml were incubated in the presence or absence of the different concentrations (100, 50, 25, 2.5, 0.25, 0.025μg/ml) of bitter melon extract into 6 well tissue culture plates. The plant extract cytotoxicity screening was performed by using 3-(4,5-dimethyl thiazol-2y1)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay. Inhibitory concentration at 50% (IC50) was determined by plotting of the extract concentration against the optical density (OD) at 570nm from MTT assay. There was a dose dependent cytotoxicity effect on Hep2 cells. At the highest concentration (100μg/ml), the plant extract completely inhibited the growth of cells and these effects gradually decreased as the dose reduced. After 48 hours incubation of the Hep2 cells at concentration of 100 μ g/ml with the extract, viability of the cells were only 26% in compare to the L929 control cells. IC50 for Hep2 cell line was 27 μ g/ml. The plant extract showed no effect on L929 cell viability and characteristics. From this study it can be suggested that whole extract from bitter melon has a dose dependent cytotoxicity effect on Hep2 cell line. Therefore, this compound may be used for inhibition of the growth of cancer cells such as human larynx carcinoma.