Effect Of HSP90β On The Leukemia Cell Line HL60 Induced By ATRA

Objective: Multidrug resistance (MDR) is a major causing of the chemotherapy failure in leukemia patients. In this study, we investigated the expression difference of heat shock protein 90β(HSP90β) mRNA and protein between all-trans retinoic acid(ATRA) sensitive leukemia cell line HL60 and its resistant cell line HL60/ATRA to explore the effect of HSP90βon the ATRA multidrug resistance in leukemia.Methods: HL60/ATRA cell line was constructed by increasing ATRA concentration stepwisely and intermittently. The proliferation and sensitivity to anticancer drugs (VCR, CTX, VP-16, ADM) of HL60 and HL60/ATRA were tested by MTT assay. The cell cycle was analyzed using flow cytometry (FCM). The expression of HSP90βin HL60 cells and HL60/ATRA cells was detected with RT-PCR(reverse transcription PCR) and Western blot.Results: HL60/ATRA was successfully constructed. The transcription and protein expression of HSP90βin HL60/ATRA cells was higher than that of HL60 cells statistically (P<0.01). The proliferation and cell cycle indicate that there is not statistical significance(P>0.05) ; The drug resistant index of HL60/ATRA cells to VCR, CTX, VP-16 and ADM increased to 10.74, 5.51, 4.01 , 3.24, compared with HL60 cells respectively.Conclusion: ATRA could induce the high expression of HSP90βin HL60 cells. The sensitivity to anticancer drugs of HL60/ATRA induced by ATRA was decreased, but drug resistance was increased, which inferred us that HSP90βmay play an important role in the development of ATRA multidrug resistance.