丙戊酸钠联合三氧化二砷诱导多发性骨髓瘤RPMI 8226细胞凋亡及其机制研究

本研究旨在探索丙戊酸钠联合三氧化二砷对多发性骨髓瘤RPMI8226细胞凋亡的影响及其相关机制.利用CCK-8法检测不同浓度的丙戊酸钠、三氧化二砷单药和两药联合应用对RPMI 8226细胞增殖的抑制作用.采用流式细胞术检测细胞凋亡情况.半定量RT-PCR和Western blot分别检测各组BCL-2、BAX、caspase-8及caspase-9的mRNA和蛋白表达水平的变化.结果表明：丙戊酸钠及三氧化二砷均可抑制RPMI 8226细胞增殖,两者联合应用有协同作用（Q值大于1.15）.联合用药组RPMI 8226细胞凋亡率较单药组明显增加（P＜0.05）.与丙戊酸钠或三氧化二砷单药组相比,联合用药组RPMI 8226细胞BCL-2 mRNA及蛋白表达水平下降,BAX、caspase-8及caspase-9mRNA及蛋白表达水平上调.结论：丙戊酸钠和三氧化二砷有协同抑制RPMI 8226细胞增殖和诱导凋亡的作用,这可能与BCL-2表达下调,BAX、caspase-8及caspase-9表达上调有关.

Apoptosis-inducing Effect of Valproic Acid Combined with Arsenic Trioxide on RPMI 8226 Cells and Its Mechanism

This study was aimed to investigate the apoptosis-inducing effect of valproic acid （VPA） combined with arsenic trioxide（ATO） on human multiple myeloma RPMI 8226 cells and its mechanism. The cell proliferation of RPMI 8226 cells was assayed by CCK-8 method. The cell apoptosis were detected by flow cytometry. Semiquantitative RT- PCR and Western blot were applied respectively to detect the mRNA and protein expression level of BCL-2, BAX, caspase-8 and caspase-9 gene. The results showed that both the VPA and ATO inhibited RPMI 8226 cell proliferation. The combination of ATO and VPA has synergistic effect （Q values greater than 1.15）. The RPMI 8226 cell apoptosis rate in combined drug group was significantly higher than that in single drug group （ P 〈 0.05 ）. The mRNA and protein expressions of BCL-2 gene in combined drug group decreased, while the mRNA and protein expressions of BAX, caspase-8 and caspase-9 significantly increased, compared with single drug group（ P 〈 0.05 ）. It is concluded that VPA can enhance the sensitivity of RPMI 8226 cells to ATO-induced apoptosis, which may be associated with decreasing the BCL-2 expression and increasing the BAX, caspase-8 and caspase-9 gene expression.