全反式视黄酸调控乳腺癌细胞的增殖及机制研究

STUDY ON THE EFFECT ALL-TRANS RETINOIC ACID ON PROLIFERATION OF BREAST CANCER MDA-MB-231 CELLS AND UNDERLYING MECHANISM

目的研究全反式视黄酸(ATRA)对人乳腺癌MDA-MB-231细胞增殖及ATRA与X射线照射对视黄醇类X受体α(RXRα)表达水平的影响。方法 MTT法检测细胞增殖,Western blot检测RXRα表达水平。结果 ATRA浓度在100～1000 nmol/L,72 h可抑制细胞的增殖。观察不同时间100 nmol/L的ATRA作用,24 h内,促进MDA-MB-231细胞的增殖,而作用48 h后,可抑制细胞的增殖。ATRA在100～1000 nmol/L范围内可诱导RXRα的表达,且存在浓度依赖性。100 nmol/L的ATRA作用24 h即可诱导RXRα的表达,并且存在时间依赖性。X射线照射未能诱导RXRα的表达。结论 100～1000 nmol/L的ATRA作用48 h即可抑制MDA-MB-231细胞增殖,且其对MDA-MB-231细胞RXRα蛋白表达存在浓度和时间依赖性,为ATRA用于临床乳腺癌的治疗提供了理论基础,也提示RXRα可能是ATRA抑制乳腺癌细胞增殖的机制之一。

Objective To study the effect of all-trans retinoic acid（ATRA） on proliferation of breast cancer MDA-MB-231 cells,and its mechanism.Method Cell proliferation was evaluated by MTT assay,and protein expression of RXRα was determined by Western blot.Results ATRA 100-1000 nmol/L at 72 h inhibited the growth in dose dependent manner.After being treated with 100 nmol/L ATRA for less than 24h,obvious proliferation of MDA-MB-231 cells was observed,but showed inhibition when more than 48 h.Within 100-1000 nmol/L,ATRA could induce the expression of RXRα in concentration-dependent manner.After acting for 24 h,100 nmol/L ATRA could induce the expression of RXRα in time-dependent manner.X-ray irradiation at the rate of 0.5Gy/min could not induce the expression of RXRα.Conclusion ATRA 100-1000 nmol/L could inhibit proliferation of MDA-MB-231 cells after action for 48 h.The effect of ATRA on RXRα expression was concentration and time-dependent.RXRα might be the mechanism that ATRA regulated proliferation of MDA-MB-231 cells,and it provided the basis for ATRA to be used in clinic.