BET抑制剂JQ1协同组蛋白去乙酰化酶抑制剂SAHA抗骨肉瘤的实验研究

Synergistic effect and molecular mechanism of BET inhibitor JQ1 and HDAC inhibitor SAHA on osteosarcoma

目的探讨溴结构域及外端结构域(BET)抑制剂JQ1联合组蛋白去乙酰化酶抑制剂伏立诺他(SAHA)抗骨肉瘤的作用及相关分子机制。方法 JQ1单用、SAHA单用及JQ1联合SAHA分别处理骨肉瘤细胞SJSA1和MNNG/HOS后,利用MTT法结合药物协同指数(CI)检测药物对细胞的生长抑制作用并评定协同效果,克隆形成检测生长抑制作用,流式细胞仪检测细胞凋亡,Western blot法检测相关蛋白表达水平的改变。结果 JQ1联合SAHA协同抑制骨肉瘤细胞系SJSA1和MNNG/HOS生长,克隆形成及流式细胞仪检测证明JQ1联合SAHA能够协同抑制骨肉瘤生长并促进其凋亡,并明显上调Bax、下调Bcl-2蛋白的表达。结论 JQ1联合SAHA能够协同抑制骨肉瘤细胞生长、诱导其凋亡,其中Bax/Bcl-2可能是重要的靶点。

Objective To study the anti-tumor effect and molecular mechanism of bromodomain and extra-terminal domain（BET） inhibitor JQ1 combinded with histone deacetylase inhibitor（HDACI） suberoylanilide hydroxamic acid（SAHA）.Methods MTT assay and drug combination index were used to evaluate the synergistic effect of JQ1 and SAHA on anti-proliferation in osteosarcoma cell lines SJSA1 and MNNG/HOS. Flow cytometry and clone formation were used to detect theapoptosis. In the end,underlying molecular mechanisms were explored by Western blot. Results The results of MTT assaysand drug combination index suggested that JQ1 and SAHA inhibited tumor proliferation synergistically in SJSA1 and MNNG/HOS. Flow cytometry and clone formation confirmed the antitumor effect. Furthermore,this combined pharmacotherapysignificantly induced up regulation of Bax and down regulation of Bcl-2. Conclusions Combing JQ1 and SAHA possessedsynergistically anti-tumor effect and induced apoptosis in ostesosarcoma. Bax/Bcl-2 might be a potent target in this process.