Anticancer effects of various Iranian native medicinal plants on human tumor cell lines.

In this study the antineoplastic activity of methanolic extracts of six medicinal plants that are native to Iran, including Galium mite, Ferulago angulata, Stachys obtusicrena, Cirsium bracteosum and Echinophora cinerea was investigated. Different tumor cell lines were exposed to the extracts and cytotoxic analysis using MTT colorimetric assay was performed. Quantification of percentage of cells undergoing apoptotic changes by flow cytometry, and DNA fragmentation analysis on sensitive cell lines was then carried out. Results obtained indicated that almost all of the extracts more or less had the capacity to decrease the proliferation of tumor cells. Among the plants, the highest activity against K562 leukemia cell line was found for E. cinerea and C. bracteosum with IC50 less than 20 microg/ml followed by G. mite with IC50 of 39.8 microg/ml. F. angulata and E. cinerea, mostly inhibited Jurkat cells proliferation (IC50 less than 8 microg/ml). Fifty percent inhibition of Fen bladder cell carcinoma due to exposure to F. angulata and E. cinerea was found at concentrations of nearly 180 microg/ml. A549, a lung carcinoma cell, was mostly affected by S. obtusicrena (IC50 more than 200 microg/ml). In flow cytometry analysis, C. bracteosum, E. cinerea, F. angulata and S. obtusicrena extracts demonstrated no remarkable effects on the cell cycle profile of K562 and Jurkat cells. Moreover, in DNA fragmentation analysis of treated cells, no ladder formation was detected. In contrary, G. mite caused more than 40% apoptosis in the K562 and Jurkat cells. In DNA fragmentation analysis G. mite extract produced ladder formation in these cells. In conclusion, these results indicated that the extracts used in this study have anti tumor activity particularly against the leukemia cell lines and that apoptosis is the possible cause of cell death observed due to the extract of G. mite.