OBJECTIVETo investigate the effect of Luteolin alone or combination with chemotherapentic drugs on the cytoxicity of cancer cells.

METHODSCultured A549, Hela, MCF-7, AGS, MGC-803, Caco2 and HepG2 cells were treated with Luteolin or the combination of Luteolin with other chemotherapeutic agents (Bexarotene, Cisplatin and Bleomycin). Cell viability was measured by MTS assay and IC(50) was calculated.

RESULTSThe IC(50) of Bexarotene to Hela cells was 2 micromol/L, but with the combination of 5 micromol/L of Luteolin that reduced to 0.2 micromol/L. However, the combination of Bexarotene and Luteolin did not show significant benefit in MGC-803, HepG2 cells, Caco2 and MCF-7 cells. The IC(50) of Cisplatin to Hela cells was over 30 micromol/L,but it decreased to 3 micromol/L in the presence of 5 micromol/L Luteolin; Luteolin also sensitized Cisplatin in MGC-803, HepG2 and A549 cells studied. The IC(50) of Bleomycin to Hela cells was over 100 micromol/L, but it was about 1 micromol/L in the presence of 5 micromol/L Luteolin. A549 cells were resistant to Bleomycin with an IC(50) of 100 micromol/L, 10 micromol/L Luteolin greatly enhanced the cytotoxicity of Bleomycin to the cells with the IC(50) of about 10 micromol/L. The inhibitions of MGC-803, HepG2, A549 and AGS cells didn't change by combination of Luteolin.

CONCLUSIONLow concentration of Luteolin has little toxic effect on the cancer cell lines tested in the study, but it can sensitize chemotherapeutic drugs in various cancer cell lines.