FTY720 exerts its chemosensitization effect in HCT-8 and HCT-8/5-Fu cell lines by promoting cell apoptosis and inhibiting P-gp and MRP1, which could be applied as a potential co-adjuvant therapeutic modality.

A bstractThe early grow th response gene-1 (Egr-1) is a tum or suppressor which plays an im portant role in cell growth, differentiation and apoptosis. Egr-1 has been shown to be down-regulated in m any types of tum or tissues. Trifluoperazine (TFP), a phenothiazine class of antipsychotics, restored serum -induced Egr-1 expression in several cancer cell lines. W e investigated the effect of Egr-1 expression on the TFP-induced inhibition of cell growth. Ectopic expression of Egr-1 enhanced the TFP-induced antiproliferative activity and downregulated cyclin D1 level in U87M G gliom a cells. Our results suggest that antipsychotics TFP exhibits antiproliferative activity through up-regulation of Egr-1.