Hypericum perforatum L. (St. John's wort) is a medicinal plant used for many pathologies, especially for the treatment of mild to moderate @entity308 . In the present study we have investigated the cytotoxic activity of the locally collected (Epirus region) Hypericum perforatum L. against cultured @entity1 and @entity150 cell lines. The lipophilic extract of the herb, prepared using @entity8144 , induced apoptosis displaying LC(50) values at concentrations as low as 4 and 5 microg/mL. A fraction of this extract displayed 60 % cell growth inhibition at a concentration of 0.95 microg/mL. Evaluating the importance of various biologically active components of the extract, it was found that hypericins ( @entity19486 , @entity55882 , etc.) were identified only in the methanolic (lipophobic) extract of the herb, and not in the active lipophilic extract. In addition, @entity22738 concentrations in the lipophilic extract and its most active fraction, were 0.94 microg/mL, and 0.17 microg/mL, respectively, while the active cytotoxic concentration of pure hyperforin appeared in the range of 1.8 microg/mL - 5.0 microg/mL. Therefore, pure hyperforin does not seem to contribute significantly to the @entity137 activity. Chlorophylls were identified in low, not significantly different, concentrations in all extracts and fractions and were not correlated to the biological activity. Owing to the combination of significant cytotoxic activity, natural abundance and low @entity137 , the lipophilic extract of Hypericum perforatum holds the promise of being an interesting, new, antiproliferative agent against @entity150 that deserves further investigation.

The lipophilic extract of Hypericum perforatum exerts significant cytotoxic activity against XXXX and NBT-II @entity150 cells.

@entity1 :: ('9606', 'Species') :: ['T24'] @entity308 :: ('MESH:D003866', 'Disease') :: ['depression'] @entity22738 :: ('MESH:C001654', 'Chemical') :: ['hyperforin'] @entity137 :: ('MESH:D064420', 'Disease') :: ['toxicity', 'cytotoxicity'] @entity8144 :: ('MESH:C004544', 'Chemical') :: ['petroleum ether'] @entity150 :: ('MESH:D001749', 'Disease') :: ['NBT-II bladder cancer', 'bladder cancer'] @entity55882 :: ('MESH:C056602', 'Chemical') :: ['pseudohypericin'] @entity19486 :: ('MESH:C004965', 'Chemical') :: ['hypericin']
@entity1 :: (9606,Species) :: ['T24']
