RESUMO
OBJECTIVE: To investigate the effect of curcumin on indoleamine 2, 3 -dioxygenase (IDO) expression induced by IFN-gamma in cancer cells. METHODS: A431, HeLa, HepG2, CNE2 cells were treated with curcumin for 24 hours, then the cell proliferation was detected by methyl thiazolyl tetrazolium (MTF) assay. The effects of curcumin on IDO expression induced by IFN-gamma in these cancer cells were demonstrated by Western blot. The transcription of interferon responsive factor-1 (IRF-1), which was a key transcription factor regulating IDO expression, was analyzed by reverse transcription polymerase chain reaction (RT-PCR) under the treatment of curcumin. RESULTS: Curcumin inhibited the expression of IDO in these cancer cells. However, curcumin did not inhibit the transcription of IRF-1 in cancer cells. CONCLUSION: Curcumin could inhibit the expression of IDO in cancer cells.
