miR-338-3p在恶性肿瘤中的表达异常及其表观遗传组蛋白的修饰位点

Objective: To evaluate the expression of miR-338-3p among various types of cancers and investigate the histone modification sites of epigenetics. Methods: The data of miR-338-3p expression profile among 15 cancer types were obtained from TCGA Pan-Cancer database (The Cancer Genome Atlas). The expression of miR-338-3p in 45 normal tissues and 366 malignancy tissues of gastric cancer was analyzed. The potential histone modification site in miR-338-3p promoter region was predicated with CRCH37 (Genome Reference Consortium). Chromatin immune coprecipitation (ChIP) and PCR were adopted to detect the modification sites of histone. Results: Compared with its counterpart, the miR-338-3p in colon adenocarcinoma, kidney renal clear cell carcinoma and liver hepatocellular carcinoma showed a significantly higher expression (P<0.05), but a significantly lower one in esophageal carcinoma, head and neck squamous cell carcinoma, kidney chromophobe, kidney renal papillary cell carcinoma, lung squamous cell carcinoma and thyroid carcinoma cancer (P<0.05). miR-338-3p expression was decreased in 45 normal gastric tissues compared with in 366 gastric cancer tissues. H3K9m2 and H3K4m3 were considered as two potential sites of histone modification of epigenetics which might induce the down-regulation of miR-338-3p in gastric cancer. Conclusion: miR-338-3p expression was decreased in gastric cancer and closely associated with two potential sites of histone modification of H3K9m2 and H3K4m3.