槲皮素通过生长抑制特异性基因5调节微小RNA-23a-3p和磷脂酰肌醇3激酶/蛋白激酶B信号通路抑制垂体神经内分泌肿瘤的增殖机制

Quercetin inhibits the proliferation of pituitary neuroendocrine tumors by regulating miR-23a-3p and PI3K/AKT signaling pathway through GAS5

目的:探讨槲皮素对垂体神经内分泌肿瘤(PitNETs)生长的抑制作用及其可能机制。方法:通过Starbase工具预测生长抑制特异性基因5(GAS5)与微小RNA-23a-3p(miR-23a-3p)结合情况,双荧光素酶报告实验和RNA免疫沉淀测定GAS5和miR-23a-3p之间的结合关系。体外培养人垂体瘤细胞系RC-4B/C,分为对照组(Control)、槲皮素组(Quercetin)、GAS5抑制组(Si-GAS5)和槲皮素+si-GAS5组(Quercetin+si-GAS5),对比分析槲皮素对GAS5、miR-23a-3p及磷脂酰肌醇3激酶(PI3K)/蛋白激酶B(AKT)信号通路的影响,以及人垂体瘤复苏细胞(RC-4B/C)生长和侵袭能力的影响。结果:Starbase工具预测GAS5与miR-23a-3p结合,双荧光素酶报告实验和RNA免疫沉淀测定揭示了GAS5和miR-23a-3p之间的直接结合。槲皮素促进GAS5的表达,抑制miR-23a-3p和PI3K/AKT的表达,抑制RC-4B/C细胞的增殖和侵袭(均P<0.05);下调GAS5、miR-23a-3p表达增多,促进RC-4B/C细胞的增殖和侵袭(均P<0.05);槲皮素可以逆转GAS5下调引起的miR-23a-3p、PI3K/AKT表达增加,抑制RC-4B/C细胞的增殖和侵袭(均P<0.05)。结论:槲皮素可能通过促进GAS5表达竞争性抑制miR-23a-3p,降低了PI3K/AKT,抑制垂体神经内分泌肿瘤的生长。

Objective:To investigate the inhibitory effect of quercetin on the growth of pituitary neuroendocrine tumors and its possible mechanism.Methods:Starbase tool was used to predict the combination of growth arrest-specific transcripts(GAS5)with miR-23a-3p.Dual luciferase assay and RNA immunoprecipitation were used to determine the binding relationship between GAS5 and miR-23a-3p.Human pituitary tumor cell line RC-4B/C was cultured in vitro and divided into control group(control group),quercetin group(quercetin group),GAS5 inhibition group(si-GAS5 group)and quercetin+si-GAS5 group.The effects of quercetin on GAS5,miR-23a-3p and PI3K/AKT signaling pathway,as well as the effects on the growth and invasion ability of RC-4B/C tumor cells were compared and analyzed.Results:The Starbase tool predicted GAS5 binding to miR-23a-3p,and dual luciferase reporting assay and RNA immunoprecipitation assay revealed the direct binding between GAS5 and miR-23a-3p.Quercetin promoted the expression of GAS5,inhibited the expression of miR-23a-3p and PI3K/AKT,and inhibited the proliferation and invasion of RC-4B/C cells(P<0.05).Down-regulated GAS5 and increased miR-23a-3p expression promoted the proliferation and invasion of RC-4B/C cells(all P<0.05).Quercetin could reverse the increased expression of miR-23a-3p and PI3K/AKT caused by GAS5 downregulation,and inhibit the proliferation and invasion of RC-4B/C cells(all P<0.05).Conclusion:Quercetin may competitively inhibit miR-23a-3p by promoting GAS5 expression,reduce PI3K/AKT,and inhibit the growth of pituitary neuroendocrine tumors.