miR-206 inhibits renal cell cancer growth by targeting GAK

Renal cell cancer (RCC) remains one of the most lethal types of cancer in adults. MicroRNAs (miRNAs) play key roles in the pathogenesis of RCC. The role of miR-206 in RCC has not been fully understood. The purpose of this study was to examine the role of miR-206 in the regulation of proliferation and metastasis of RCC and the possible mechanism. miR-206 expression was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in RCC cell lines (786-O and OS-RC-2 cells) and clinical samples. MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] method, colony formation and transwell assay were used to detect the tumor-suppressing ability of miR-206 in RCC. Luciferase assay was performed to verify the precise target of miR-206. The results showed that the expression of miR-206 was significantly down-regulated in RCC tissues and cells. The expression level of cyclin G-associated kinase (GAK), a master regulator of tumor proliferation and metastasis, was up-regulated with the decrease in miR-206 in RCC tissues as well as RCC cell lines. In addition, the miR-206 inhibitor promoted the proliferation, migration and invasion of 786-O and OS-RC-2 cells. Bioinformatics combined with luciferase and Western blot assays revealed that miR-206 inhibited the expression of GAK. Moreover, miR-206 regulates RCC cell growth partly through targeting GAK. Our study indicated that miR-206 functions as a tumor suppressor in regulating the proliferation, migration and invasion of RCC by directly targeting GAK, and it holds promises as a potential therapeutic target for RCC.

The multiple functions of RNA helicases as drivers and regulators of gene expression

RNA helicases comprise the largest family of enzymes involved in the metabolism of mRNAs, the processing and fate of which rely on their packaging into messenger ribonucleoprotein particles (mRNPs). In this Review, we describe how the capacity of some RNA helicases to either remodel or lock the composition of mRNP complexes underlies their pleiotropic functions at different steps of the gene expression process. We illustrate the roles of RNA helicases in coordinating gene expression steps and programmes, and propose that RNA helicases function as molecular drivers and guides of the progression of their mRNA substrates from one RNA-processing factory to another, to a productive mRNA pool that leads to protein synthesis or to unproductive mRNA pools that are stored or degraded.

miR-590-3p suppresses cancer cell migration, invasion and epithelial-mesenchymal transition in glioblastoma multiforme by targeting ZEB1 and ZEB2

Invasion and migration of glioblastoma multiforme (GBM) is a multistep process and an important phenotype that causes this disease to invade surrounding tissues in the brain. The purpose of this study was to determine the role of miR-590-3p in regulation of epithelial mesenchymal transition (EMT) and metastasis of GBM cells. Expression levels of miR-590-3p in 15 GBM specimens with adjacent tissues and five GBM cell lines were assessed by quantitative RT-PCR. We found that miR-590-3p was down-regulated in detected GBM tissue samples and all of the GBM cell lines. In addition, Ectopic expression of miR-590-3p suppressed and miR-590-3p-in promoted EMT, migration, and invasion in U87MG and A172 cells. Bioinformatics coupled with luciferase and Western blot assays also revealed that miR-590-3p inhibited expression of ZEB1 and ZEB2, which are master regulators of tumor metastasis. Our study first indicates that miR-590-3p functions as a suppressor of GBM EMT and metastasis by targeting ZEB1 and ZEB2, and it may be a therapeutic target for metastatic GBM.