This study was carried out to evaluate cytotoxic effects of Houttuynia cordata THUNB extracts on A549 (lung cancer), MDA-MB231 (breast cancer), SNU-C4 (colon cancer) and B16 (mouse melanoma) cell lines. We have determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazoliumbromide (MTT) assay. The 150 ㎍/㎖ concentration of methanol extract (63.81 %) of Houttuynia cordata THUNB was shown significantly antitoxic activity on A549 cell lines. The order of cytotoxicity fractions of methanol from Houttuynia cordata THUNB extracts against cancer cell lines in vitro is as follows : hexane fraction layer > chloroform fraction layer > ethyl acetate fraction layer > buthanol fraction layer > water fraction layer. These results suggest that the hexane fraction of methanol extract from Houttuynia cordata THUNB extract may be a valuable choice for the development of antitumor agents.
