VAMP8 facilitates cellular proliferation and temozolomide resistance in human glioma cells
VAMP8 facilitates cellular proliferation and temozolomide resistance in human glioma cells
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VAMP8 促进人胶质瘤细胞的细胞增殖和替莫唑胺耐药性
DOI：
10.1093/neuonc/nou219
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发表时间：
2015-03-01
期刊：
影响因子：
15.9
通讯作者：
Lu, Daru
中科院分区：
文献类型：
--
作者：
Chen, Yuanyuan;Meng, Delong;Lu, Daru
背景恶性胶质瘤是成人常见的致死性原发性脑肿瘤。在这里，我们确定了一种新的癌蛋白，囊泡相关膜蛋白8（VAMP 8），并研究其在胶质瘤的肿瘤发生和化疗耐药性的作用。采用定量PCR和Western blot检测基因和蛋白的表达。采用Pearson卡方检验对282例胶质瘤标本和12例正常对照进行组织学分析。使用对数秩检验和考克斯比例风险回归进行生存分析。使用细胞计数试剂盒-8进行细胞增殖和细胞毒性测定。共聚焦显微镜和Western blot检测细胞自噬。VAMP 8在人脑胶质瘤标本中显著过表达，可能成为胶质瘤患者预后和治疗预测的潜在新标志物。VAMP 8的过表达促进了细胞在体外和体内的增殖，而VAMP 8的敲低则通过将细胞周期阻滞在G 0/G1期来减弱胶质瘤的生长。此外，VAMP 8通过提高自噬蛋白的表达水平和自噬体的数量而有助于替莫唑胺（TMZ）抗性。通过siRNA介导的自噬相关基因5（ATG 5）或突触融合蛋白17（STX 17）的敲低进一步抑制自噬可逆转VAMP 8过表达细胞对TMZ的耐药性，而VAMP 8的沉默可削弱胶质瘤细胞的自噬通量并减轻TMZ耐药性。我们的研究结果确定VAMP 8作为一种新的癌基因，通过促进胶质瘤细胞增殖和治疗耐药性。以VAMP 8为靶点可能成为治疗胶质瘤的一种潜在的治疗方案。
Background. Malignant glioma is a common and lethal primary brain tumor in adults. Here we identified a novel oncoprotein, vesicle-associated membrane protein 8 (VAMP8), and investigated its roles in tumorigenisis and chemoresistance in glioma.Methods. The expression of gene and protein were determined by quantitative PCR and Western blot, respectively. Histological analysis of 282 glioma samples and 12 normal controls was performed by Pearson's chi-squared test. Survival analysis was performed using the log-rank test and Cox proportional hazards regression. Cell proliferation and cytotoxicity assay were conducted using Cell Counting Kit-8. Autophagy was detected by confocal microscopy and Western blot.Results. VAMP8 was significantly overexpressed in human glioma specimens and could become a potential novel prognostic and treatment-predictive marker for glioma patients. Overexpression of VAMP8 promoted cell proliferation in vitro and in vivo, whereas knockdown of VAMP8 attenuated glioma growth by arresting cell cycle in the G0/G1 phase. Moreover, VAMP8 contributed to temozolomide (TMZ) resistance by elevating the expression levels of autophagy proteins and the number of autophagosomes. Further inhibition of autophagy via siRNA-mediated knockdown of autophagy-related gene 5 (ATG5) or syntaxin 17 (STX17) reversed TMZ resistance in VAMP8-overexpressing cells, while silencing of VAMP8 impaired the autophagic flux and alleviated TMZ resistance in glioma cells.Conclusion. Our findings identified VAMP8 as a novel oncogene by promoting cell proliferation and therapeutic resistance in glioma. Targeting VAMP8 may serve as a potential therapeutic regimen for the treatment of glioma.