Let-7b-5p inhibits proliferation and motility in squamous cell carcinoma cells through negative modulation of KIAA1377.

Abstract

KIAA1377 has been found to be linked with lymph node metastasis in esophageal squamous cell carcinoma (SCC) in our previous study; however, the regulation of KIAA1377 remains far from understood. Herein, to understand the regulation of KIAA1377 from the angle of microRNA (miRNA)-messenger RNA (mRNA) modulation in the setting of SCC cells, the basal level of KIAA1377 was determined by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis in KYSE-150 and HeLa cells; biological roles of KIAA1377 contributing in the proliferation, migration, and invasion were evaluated using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT), wound-healing and Transwell assays, respectively, after KIAA1377 was knocked out mediated by the CRISPR-Cas9 system. Bioinformatic prediction revealed that let-7b-5p was a putative miRNA regulating KIAA1377, which was ensuingly validated by the luciferase reporter assay; after which, variation of KIAA1377 expression was further verified by qRT-PCR and western blot analysis. Moreover, the biological roles of let-7b-5p in proliferation, migration, and invasion of KYSE-150 and HeLa cells were also evaluated. It was exhibited that KIAA1377 was able to promote the proliferation and motility of both KYSE-150 and HeLa cells, which can be reverted by re-expression of let-7b-5p. The luciferase reporter assay verified that let-7b-5p can diametrically target KIAA1377. Collectively, our data demonstrated that let-7b-5p can directly but negatively regulate KIAA1377 in SCC cell lines, Ecal109, and HeLa cells.