MiR-4733-5p promotes gallbladder carcinoma progression via directly targeting kruppel like factor 7

Gallbladder carcinoma (GBC) is highly aggressive with poor prognosis. Accumulating reports show that miRNAs play critical roles in tumor progression. Previous studies have identified several miRNAs that promoted or inhibited GBC cell proliferation and/or metastasis. Here, we used the Gene Expression Omnibus (GEO) dataset to identify dysregulated miRNAs in GBC, followed by validating the upregulation of the miR-4733-5p and downregulation of kruppel-like factor 7 (KLF7) in GBC biopsies by quantitative real-time PCR (RT-qPCR), in situ hybridization (ISH) staining, and immunohistochemistry (IHC) assays. GBC cell proliferation and invasion capacities mediated by miR-4733-5p were evaluated by a series of function assays in vitro, including CCK-8, colony formation assay, wound healing assay and transwell assay. Xenograft tumor model found that miR-4733-5p promoted GBC tumor growth in vivo. This study clarified that miR-4733-5p was upregulated in GBC and promoted GBC cell proliferation via directly binding to 3’ untranslated region (UTR) of KLF, which was downregulated and prohibited the proliferation and migration of GBC cells.

胆囊癌（Gallbladder carcinoma, GBC）侵袭性极强且预后不良。已有大量研究证实，微小RNA（miRNAs）在肿瘤进展过程中发挥关键调控作用。既往研究已鉴定出若干可促进或抑制胆囊癌细胞增殖与/或转移的微小RNA。本研究借助基因表达综合数据库（Gene Expression Omnibus, GEO）数据集，筛选出胆囊癌组织中差异表达的微小RNA；随后通过实时定量聚合酶链反应（quantitative real-time PCR, RT-qPCR）、原位杂交（ISH）染色及免疫组化（IHC）实验，验证了胆囊癌活检组织中miR-4733-5p的上调表达与krüppel样因子7（KLF7）的下调表达。本研究通过CCK-8实验、集落形成实验、划痕愈合实验及Transwell实验等一系列体外功能实验，评估了miR-4733-5p介导的胆囊癌细胞增殖与侵袭能力；通过异种移植瘤模型证实，miR-4733-5p可在体内促进胆囊癌肿瘤生长。本研究明确：miR-4733-5p在胆囊癌中呈上调表达，可通过直接结合KLF的3'非翻译区（3' untranslated region, UTR）促进胆囊癌细胞增殖；而该KLF分子本身呈下调表达，可抑制胆囊癌细胞的增殖与迁移。