Objective:To investigate the effects of Crocin on proliferation regulation after silencing PLCεgene expression by RNAi interference in human bladder cancer cells BIU-87.Methods:BIU-87 cells were transfected with plasmid pGenesil-PLCε.The experiment was designed as five groups to compared with each other

they were non-transfected cells as control group

pGenesil-NP negative plasmid transfected group

pGenesil-PLCεplasmid transfected group

Crocin group

pGenesil-PLCεplasmid transfected together with Crocin group.The influence on proliferation of every group was determined by methyl thiazolyl tetrazolium(MTT).The expression of PLCεmRNA of BIU-87 cells after transfection with the plasmid pGenesil-PLCεwas observed by RT-PCR.RT-PCR and Western-blot were used to detect cyclin D1 and PCNA expression. Results:78.06% mRMA of PLCεwas reduced clearly after transfected with plasmid pGenesil-PLCεin BIU-87 cells. pGenesil-PLCεplasmid transfected together with crocin group could enhance the inhibitive effect of Crocin on proliferation up to 45.30% at 48h

which was strikingly compared with the pGenesil-PLCεplasmid transfected group and the Crocin group (P<0.01).Both RT-PCR and western-blot indicated that the expression of PCNA

CyclinD1 both in mRNA and protein were markedly decreased in the RNAi together with Crocin group compared with the RNAi group(P<0.05).Compared with the Crocin group

The expression of PCNA both in mRNA and protein were reduced remarkably(P<0.05)

the expression of CyclinD1 protein was decreased clearly(P<0.05)in the RNAi together with Crocin group

but the expression of CyclinD1 mRNA had no significant difference between the two groups(P>0.05).Conclution:RNAi PLCεtogether with Crocin can enhance the inhibit effect of Crocin

they can further reduce PC NA

CyclinD1 expressionthe was the mechanism.