MACC1通过调控MCT1表达影响胃癌化疗敏感性

MACC1 Affected the Chemosensitivity of Gastric Cancer by Regulating MCT1 Expression

目的 探讨结肠癌转移相关基因-1(metastasis-associated in colon cancer 1,MACC1)调控靶基因单羧酸转运蛋白1(monocarboxylate transporter 1,MCT1)在胃癌化疗敏感性中的作用。方法 使用基因表达谱交互分析(gene expression profile interactive analysis, GEPIA)胃癌组织和癌旁组织中MACC1的表达,并分析MACC1的表达与胃癌患者总生存期(overall survival, OS)的相关性。将AGS细胞(胃腺癌细胞)分为载体组(Vector组)和MACC1过表达质粒组(MACC1组),以及将顺铂耐药胃腺癌细胞(cisplatin-resistant gastric adenocarcinoma cells, AGS/DDP)分为MACC1敲低组(si-MACC1组)和对照组(si-NC组)。采用实时荧光定量逆转录聚合酶链反应(real-time quantitative reverse transcription polymerase chain reaction, RT-PCR)和Western blot检测AGS细胞中MACC1、MCT1的表达。通过细胞计数试剂盒8(cell-counting kit-8,CCK-8)法分析细胞活力。通过双荧光素酶报告基因测定和染色质免疫沉淀(chromatin immunoprecipitation, ChIP)评估MACC1和MCT1的关系。构建体内腹膜内肿瘤模型研究MACC1的表达对AGS/DDP的影响。结果 MACC1在胃癌组织和AGS细胞中的表达异常高,并且MACC1高表达的胃癌患者预后较差。与Vector组相比,MACC1组的细胞活力和MCT1表达显著增加(P<0.05)。与si-NC组相比,si-MACC1组的细胞活力和MCT1表达显著降低(P<0.05),说明敲低MCT1基因可逆转MACC1诱导的顺铂耐药。相反,当MACC1在顺铂耐药的胃癌细胞中被敲低时,上调MCT1重新激活胃癌细胞中的顺铂耐药。双荧光素酶报告基因测定和ChIP分析表明MCT1是MACC1的下游基因,MACC1在转录水平正调控MCT1的表达。在体内实验中,MACC1敲低可以增强胃癌细胞对顺铂的敏感性。结论 MCT1是MACC1的下游基因,与顺铂耐药有关。靶向MACC1使胃癌细胞对顺铂敏感。

Objective To investigate the role of metastasis-associated in colon cancer 1(MACC1) regulating target gene monocarboxylate transporter 1(MCT1) in the chemosensitivity of gastric cancer. Methods MACC1 expression in gastric cancer and non-gastric cancer tissues of gastric cancer patients was analyzed by gene expression profile interaction analysis(GEPIA), and the correlation of MACC1 expression with overall survival(OS) in gastric cancer patients was analyzed. AGS cells(gastric adenocarcinoma cell) were divided into Vector group(Vector) and MACC1 overexpression plasmid group(MACC1), and cisplatin-resistant gastric adenocarcinoma cells(AGS/DDP) were divided into MACC1 knockdown group(si-MACC1) and control group(si-NC). The expressions of MACC1 and MCT1 in AGS were detected by real-time quantitative reverse transcription polymerase chain reaction(RT-PCR) and Western blot. Cell viability was analyzed by cell-counting kit-8(CCK-8). The relationship between MACC1 and MCT1 was assessed by dual-luciferase reporter gene assay and chromatin immunoprecipitation(ChIP). The effect of MACC1 expression on AGS/DDP was studied by vector construction of intraperitoneal tumor model in vivo. Results MACC1 expression was abnormally high in gastric cancer tissues and AGS cells, and gastric cancer patients with high MACC1 expression had poor prognosis. Compared with Vector group, cell viability and MCT1 expression in MACC1 group significantly increased(P<0.05);compared with the si-NC group, the cell viability and MCT1 expression of the si-MACC1 group significantly decreased(P<0.05), which indicated that the knockdown of MCT1 gene could reverse cisplatin resistance induced by MACC1. Conversely, when MACC1 was knocked down in cisplatin-resistant gastric cancer cells, upregulating of MCT1 reactivated cisplatin resistance in gastric cancer cells. The dual-luciferase reporter gene assay and ChIP analysis suggested MCT1 was downstream gene of MACC1, and MACC1 positively regulated the expression of MCT1 at the transcriptional level. In vivo experiment, MACC1 knockdown could enhance the sensitivity of gastric cancer cells to cisplatin. Conclusion MCT1, downstream gene of MACC1, is associated with cisplatin resistance. Targeting MACC1 sensitizes gastric cancer cells to cisplatin.