Silencing of monocarboxylate transporters via small interfering ribonucleic acid inhibits glycolysis and induces cell death in malignant glioma: An in vitro study
Silencing of monocarboxylate transporters via small interfering ribonucleic acid inhibits glycolysis and induces cell death in malignant glioma: An in vitro study
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DOI：
10.1227/01.neu.0000143034.62913.59
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发表时间：
2004-12-01
期刊：
影响因子：
4.8
通讯作者：
Sloan, AE
中科院分区：
文献类型：
--
作者：
Mathupala, SP;Parajuli, P;Sloan, AE
目的：糖酵解依赖性是恶性肿瘤的一个标志。因此，这些肿瘤产生更多的乳酸，乳酸通过单羧酸转运蛋白（MCT）从细胞中流出。我们假设：1）MCT在恶性肿瘤中的表达可能不同于正常组织的数量，亚型，或两者兼而有之;和2）沉默MCT的表达将诱导细胞内酸化，导致增殖减少和/或增加细胞death.METHODS：我们定量表达的MCT亚型在人多形性胶质母细胞瘤和胶质瘤衍生的细胞系通过Western印迹分析。丰富的或特定的胶质瘤，然后在模型U-87 MG胶质瘤细胞系通过小干扰核糖核酸介导的基因沉默和测试的抑制乳酸外流，细胞内pH值的变化，减少增殖，和/或诱导细胞death.RESULTS：MCT 1和2的主要亚型表达在人多形性胶质母细胞瘤和胶质瘤衍生的细胞系。相反，MCT 3是正常脑中主要表达的同种型。MCT 1和2特异性小干扰核糖核酸将U-87 MG细胞中这些亚型的表达降低至几乎不可检测的水平，并使乳酸外排单独降低30%，联合降低85%，同时使细胞内pH值降低0.6个单位（细胞内H+增加4倍）。延长沉默的两个MCT分别减少75%和92%的组合，作为测量表型和流式细胞仪analysis.CONCLUSION：MCT靶向显着降低了由凋亡和坏死介导的U-87 MG细胞的生存能力。这表明该策略可能是治疗恶性胶质瘤患者的一种有用的治疗途径。
OBJECTIVE: Dependence on glycolysis is a hallmark of malignant tumors. As a consequence, these tumors generate more lactate, which is effluxed from cells by monocarboxylate transporters (MCTs). We hypothesized that 1) MCT expression in malignant tumors may differ from normal tissue in quantity, isoform, or both; and 2) silencing MCT expression would induce intracellular acidification, resulting in decreased proliferation and/or increased cell death.METHODS: We quantified expression of MCT isoforms in human glioblastoma multiforme and glioma-derived cells lines by Western blot analysis. MCTs that were abundant or specific to glioma then were targeted in the model U-87 MG glioma cell line via small interfering ribonucleic acid-mediated gene silencing and tested for inhibition of lactate efflux, intracellular pH changes, reduced proliferation, and/or induction of cell death.RESULTS: MCT 1 and 2 were the primary isoforms expressed in human glioblastoma multiforme and glioma-derived cell lines. In contrast, MCT 3 was the predominantly expressed isoform in normal brain. Small interfering ribonucleic acid specific for MCT 1 and 2 reduced expression of these isoforms in U-87 MG cells to barely detectable levels and reduced lactate efflux by 30% individually and 85% in combination, with a concomitant decrease of intracellular pH by 0.6 units (a fourfold increase in intracellular H+). Prolonged silencing of both MCTs reduced viability by 75% individually and 92% in combination, as measured by both phenotypic and flow cytometric analyses.CONCLUSION: MCT targeting significantly reduced the viability of U-87 MG cells mediated by both apoptosis and necrosis. This indicates that the strategy may be a useful therapeutic avenue for treatment of patients with malignant glioma.