CURCUMIN DOES NOT ALTER THE PHORBOL ESTER EFFECT ON CELL-CELL TRANSFER OF LUCIFER YELLOW CH

Curcumin, the dietary pigment responsible for the yellow color of curr y, has been reported to be a potent inhibitor of tumor promotion in mo use epidermis. Since most tumor promoters inhibit cell-cell communicat ion, we have examined the effect of curcumin on the reduction of gap j unctional intercellular communication induced by the phorbol ester pho rbol-12,13-dibutyrate (PDBu) in BALB/c 3T3 cells. Treatment of cells w ith 50 mu M curcumin slightly inhibited the dye coupling evaluated by intercellular transfer of a fluorescent dye Lucifer Yellow CH; however , lower concentrations of curcumin did not affect the level of interce llular communication. Addition of 200 nM PDBu caused a rapid reduction of dye coupling, which was not altered by either pretreatment or simu ltaneous curcumin addition.