miR-148a-3p调节胃癌多重耐药的机制研究

发布时间：2018-06-30 10:59

本文选题：miR-148a-3p + 胃癌　；参考：《蚌埠医学院》2015年硕士论文

【摘要】：背景:胃癌属于全世界高发的恶性肿瘤之一,我国胃癌发病率占恶性肿瘤中占首位,死亡率占所有恶性肿瘤中占第四位,其临床治疗方法通常是手术切除合并放化疗为主。然而,随着化疗在肿瘤病患中的不断开展,多药耐药问题日益凸显。有研究报道,耐药是胃癌患者死亡的主要原因。因此,研究胃癌耐药是医务工作人员亟需解决的问题。Micro RNAs是一组含量丰富,长度为20各碱基左右的单链非编码小RNA。它通过与靶基因mRNA的3,-非编码区互补配对,直接诱导靶基因mRNA降解或抑制其蛋白质合成,从而在细胞分化、凋亡、增值、新陈代谢等生命过程发挥重要作用。已有大量文献报道上调或下调肿瘤耐药相关的miRNA分子可逆转肿瘤耐药。我们参考国内外相关文献,得出miR-148a-3p与胃癌耐药相互关系尚没有报道,因此我们展开以下实验。目的:探究miR-148a-3p调节胃癌多重耐药作用机制方法:1.QRT-PCR检测比较耐药细胞系SGC7901/ADR与其亲本细胞SGC7901之间miR-148a-3p表达差异。2.采用瞬时转染miR-148a-3p mimic和inhibitor,分别上调SGC7901/ADR细胞miR-148a-3p表达量,下调SGC7901细胞miR-148a-3p表达量。通过体外MTT药敏实验检测miR-148a-3p对其细胞耐药的影响,流式细胞技术检测miR-148a-3p对细胞凋亡情况的影响。3.深入研究miR-148a-3p调节胃癌多重耐药可能的机制。结果:1.耐药细胞SGC7901/ADR中miR-148a-3p表达量低于其亲本细胞SGC7901。2.上调SGC7901/ADR细胞中miR-148a-3p表达量后,可增加耐药细胞对化疗药物的敏感性,增加细胞凋亡百分比;下调SGC7901细胞中miR-148a-3p表达后,可降低SGC7901细胞对化疗药物的敏感性,并减少细胞凋亡百分比。3.Western-blot及q RT-PCR结果显示ERBB3可能是miR-148a-3p的靶基因之一。用siRNA降低SGC7901/ADR细胞中ERBB3表达后,其对化疗药物的敏感性增加。4.Western-blot结果显示,下调SGC7901/ADR细胞中ERBB3表达后,p-Akt表达水平降低。结论:miR-148a-3p可能通过作用于其靶基因ERBB3,介导ERBB3/PI3K/Akt信号通路调节胃癌多重耐药。
[Abstract]:Background: gastric cancer is one of the most common malignant tumors in the world. The incidence of gastric cancer is the first and the mortality rate is the fourth among all malignant tumors in China. The clinical treatment of gastric cancer is usually surgical resection combined with radiotherapy and chemotherapy. However, with the continuous development of chemotherapy in cancer patients, the problem of multi-drug resistance has become increasingly prominent. Drug resistance is reported to be the leading cause of death in patients with gastric cancer. Therefore, the study of drug resistance in gastric cancer is an urgent problem for medical workers. Micro RNAs are a group of single-stranded non-coding small RNAs with rich contents and about 20 bases in length. It directly induces the degradation of target gene mRNA or inhibits its protein synthesis by complementing with the 3- non-coding region of target gene mRNA, thus plays an important role in cell differentiation, apoptosis, proliferation, metabolism and other life processes. A large number of literatures have reported that up-regulating or down-regulating miRNA molecules associated with tumor resistance can reverse drug resistance. The relationship between miR-148a-3p and gastric cancer resistance has not been reported, so we have carried out the following experiments. Aim: to investigate the mechanism of miR-148a-3p in regulating multidrug resistance in gastric cancer cell line SGC7901 / ADR and its parent cell line SGC7901. Methods: 1. The expression of miR-148a-3p in gastric cancer cell line SGC7901 / ADR was compared with that of its parent cell line SGC7901. Transient transfection of miR-148a-3p mimic and inhibitor were used to up-regulate the expression of miR-148a-3p and down-regulate the expression of miR-148a-3p in SGC7901 cells. The effect of miR-148a-3p on cell resistance was detected by MTT assay in vitro, and the effect of miR-148a-3p on cell apoptosis was detected by flow cytometry. To study the possible mechanism of miR-148a-3p regulating multidrug resistance in gastric cancer. The result is 1: 1. The expression of miR-148a-3p in SGC7901 / ADR was lower than that in SGC7901.2. After upregulation of miR-148a-3p expression in SGC7901 / ADR cells, the sensitivity of resistant cells to chemotherapeutic drugs and the percentage of apoptosis were increased, and the sensitivity of SGC7901 cells to chemotherapeutic drugs was decreased after down-regulating the expression of miR-148a-3p in SGC7901 cells. The results of Western-blot and Q RT-PCR showed that ERBB3 might be one of the target genes of miR-148a-3p. The sensitivity of ERBB3 in SGC7901 / ADR cells was increased with siRNA. 4. Western-blot results showed that the expression of ERBB3 decreased after down-regulation of ERBB3 expression in SGC7901 / ADR cells. Conclusion it is possible that the multidrug resistance of gastric cancer is mediated by the ERBB3 / PI3K / Akt signaling pathway mediated by the action of the target gene ERBB3: miR-148a-3p.
【学位授予单位】：蚌埠医学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R735.2

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