Department of Pathology, Chongqing Medical University, Chongqing, People's Republic of China.
PLoS One. 2013 Apr 23;8(4):e60369. doi: 10.1371/journal.pone.0060369. Print 2013.
Gastric cancer is the most frequent gastrointestinal tumor in adults and is the most lethal form of human cancer. Despite of the improvements in treatments, the underlying mechanism of gastric carcinogenesis is not well known. To define novel modulators that regulate susceptibility to tumorgenesis, we focused on miR-219-2-3p.
Quantitative RT-PCR was employed to investigate the level of miR-219-2-3p in gastric cancer (GC) tissues (n = 113) and their matched adjacent normal tissues (n = 113). In vitro cell proliferation, apoptosis assays, cell migration, and invasion assays were performed to elucidate biological effects of miR-219-2-3p. Since silencing of miRNA by promoter CpG island methylation may be an important mechanism in tumorgenesis, GC cells were treated with 5-aza-2'-deoxycytidine and trichostatin A, and expression changes of miR-219-2-3p were subsequently examined by quantitative RT-PCR. Finally, the methylation status of CpG island upstream of miR-219-2-3p was analyzed by methylation-specific PCR in GC tissues (n = 22).
miR-219-2-3p was down-regulated in GC and cell lines. In addition, the experiments documented the lower expression of miR-219-2-3p in GC specimens with higher grade and later stage tumors. Meanwhile, miR-219-2-3p exerted antiproliferative, proapoptotic, and antimetastatic roles and reduced levels of p-ERK1/2 in GC cells. Furthermore, 5-aza-2'-deoxycytidine and trichostatin A increased the expression (~2 fold) of miR-219-2-3p in GC cells. By methylation-specific PCR, DNA methylation in the upstream region of miR-219-2-3p was detected in both adjacent normal tissues and cancer tissues. As expected, the methylation level was considerably higher in the miR-219-2-3p down-regulated group than up-regulated group.
miR-219-2-3p is potentially involved in gastric cancer progression and metastasis by regulating ERK1/2-related signal pathways, which may provide a novel therapeutic strategy for treatment of gastric cancer. Methylation mechanism may be involved in modulating the expression level of miR-219-2-3p in gastric cancer.
胃癌是成人最常见的胃肠道肿瘤，也是人类癌症中最致命的形式。尽管治疗方法有所改进，但胃癌发生的潜在机制仍不清楚。为了确定新的调节因子来调节肿瘤易感性，我们专注于 miR-219-2-3p。
采用定量 RT-PCR 检测胃癌（GC）组织（n=113）及其配对的相邻正常组织（n=113）中 miR-219-2-3p 的水平。进行体外细胞增殖、凋亡、迁移和侵袭实验，以阐明 miR-219-2-3p 的生物学效应。由于 miRNA 因启动子 CpG 岛甲基化而沉默可能是肿瘤发生的重要机制，因此用 5-氮杂-2'-脱氧胞苷和曲古抑菌素 A 处理 GC 细胞，随后通过定量 RT-PCR 检测 miR-219-2-3p 的表达变化。最后，通过甲基化特异性 PCR 分析 GC 组织中 miR-219-2-3p 上游 CpG 岛的甲基化状态（n=22）。
miR-219-2-3p 在 GC 和细胞系中下调。此外，实验记录了 GC 标本中 miR-219-2-3p 表达水平较低的肿瘤分级和晚期肿瘤。同时，miR-219-2-3p 在 GC 细胞中发挥抗增殖、促凋亡和抗转移作用，并降低 p-ERK1/2 的水平。此外，5-氮杂-2'-脱氧胞苷和曲古抑菌素 A 可使 GC 细胞中 miR-219-2-3p 的表达增加（约 2 倍）。通过甲基化特异性 PCR，在相邻正常组织和癌症组织中均检测到 miR-219-2-3p 上游区域的 DNA 甲基化。正如预期的那样，下调组的甲基化水平明显高于上调组。
miR-219-2-3p 通过调节 ERK1/2 相关信号通路参与胃癌的进展和转移，这可能为胃癌的治疗提供新的治疗策略。甲基化机制可能参与调节胃癌中 miR-219-2-3p 的表达水平。
