Department of Thoracic Surgery, First Affiliated Hospital of Anhui Medical University, 218 Jixi Rd, Hefei, 230022, Anhui, People's Republic of China.
Mol Cell Biochem. 2018 Jun;443(1-2):139-149. doi: 10.1007/s11010-017-3218-3. Epub 2017 Nov 1.
In human esophageal squamous cell carcinoma (ESCC), miR-34a was downregulated and could inhibit in vitro cell proliferation and migration. However, the underlying mechanism was not clear yet. The expression levels of mRNA and protein were detected by quantitative real-time PCR or western blotting, respectively. MiR-34a was knocked down or overexpressed and transfected into human ESCC cell lines ECA109 and TE-13, respectively. Cell migration and wound healing assays were used to examine the effect on migration and invasion in vitro. Animal models were used to examine the role of miR-34a in metastasis in vivo. Luciferase assay was carried out to validate the potential target of miR-34a. CD44 was upregulated and miR-34a was downregulated in ESCC tissues and cell lines. The linear regression analysis showed that CD44 expression was negatively correlated with the level of miR-34a. Luciferase assay showed that miR-34a interacted with a putative binding site in the CD44 3'UTR. MiR-34a was found to negatively regulate the expression of CD44. In vitro experiment showed that miR-34a overexpression inhibited ESCC cell invasion and migration; whereas miR-34a knockdown showed reversed results. MiR-34a also inhibited esophagus tumor growth and metastasis in vivo; whereas miR-34a knockdown showed reversed results. Finally, we found that CD44 knockdown reversed the effects of miR-34a knockdown on ESCC cell invasion and migration in vitro. MiRNA-34a suppresses invasion and metastatic in ESCC by regulating CD44.
在人类食管鳞状细胞癌（ESCC）中，miR-34a 下调，可抑制体外细胞增殖和迁移。然而，其潜在机制尚不清楚。通过定量实时 PCR 或 Western blot 分别检测 mRNA 和蛋白质的表达水平。敲低或过表达 miR-34a，并分别转染到人类 ESCC 细胞系 ECA109 和 TE-13 中。采用细胞迁移和划痕愈合实验检测体外迁移和侵袭的影响。采用动物模型检测 miR-34a 在体内转移中的作用。进行荧光素酶实验以验证 miR-34a 的潜在靶标。ESCC 组织和细胞系中 CD44 上调，miR-34a 下调。线性回归分析表明 CD44 的表达与 miR-34a 的水平呈负相关。荧光素酶实验表明 miR-34a 与 CD44 3'UTR 中的一个假定结合位点相互作用。发现 miR-34a 负调控 CD44 的表达。体外实验表明 miR-34a 过表达抑制 ESCC 细胞侵袭和迁移；而 miR-34a 敲低则显示出相反的结果。miR-34a 还抑制体内食管肿瘤的生长和转移；而 miR-34a 敲低则显示出相反的结果。最后，我们发现 CD44 敲低逆转了 miR-34a 敲低对 ESCC 细胞体外侵袭和迁移的影响。miRNA-34a 通过调节 CD44 抑制 ESCC 的侵袭和转移。
