Objective:To study the effect of Crocin on the expression of VEGF-C in transitional cell carcinoma of bladder (TCCB) T24 cell. Methods:T24 cells were treated with Crocin. MTT assay was adopted to determine the inhibition rate for selecting the best effect time and concentration of Crocin. The reverse transcription polymerase chain reaction(RT-PCR) and cDNA microarray were used to evaluate VEGF-C mRNA expression of T24 cells at around the best effect time and as the Crocin concentration reached the best. Results:The growth of T24 cells was inhibited significantly(P<0.05) at 3mmol/L Crocin when treated for 48h. And there was a marked positive correlation between Crocin concentration

time and inhibition rate. RT-PCR showed that VEGF-C mRNA expression in Crocin treated group was significantly lower than that of the control group. The cDNA microarray analysis was coincided well with the RT-PCR data. Conclusion:Crocin inhibits the proliferation of T24 cells and the mechanism might be decreasing tumor angiogenesis by down-regulating the expression of VEGF-C.