miR-190b promotes colorectal cancer progression through targeting forkhead box protein P2

microRNA-190b (miR-190b) is abnormally expressed in multiple types of cancer, however, its role in colorectal cancer (CRC) is largely unknown. In the present study, it was demonstrated that miR-190b expression was upregulated in CRC cell lines compared with the normal epithelial colon cell line. Knockdown of miR-190b decreased proliferation, colony formation and invasion, and increased apoptosis of CRC cells. Furthermore, forkhead box protein P2 (FOXP2) was predicted as a target of miR-190b and further validated by luciferase activity reporter assay and western blotting. Rescue experiments showed that knockdown of FOXP2 reversed the inhibitory effects of miR-190b inhibitor on the behavior of the CRC cell lines. Taken together, the present study demonstrated the oncogenic role of miR-190b in CRC through regulation of FOXP2 expression.

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title: MicroRNA biogenesis pathways in cancer
abstract: MicroRNAs (miRNAs) are critical regulators of gene expression. Amplification and overexpression of individual 'oncomiRs' or genetic loss of tumour suppressor miRNAs are associated with human cancer and are sufficient to drive tumorigenesis in mouse models. Furthermore, global miRNA depletion caused by genetic and epigenetic alterations in components of the miRNA biogenesis machinery is oncogenic. This, together with the recent identification of novel miRNA regulatory factors and pathways, highlights the importance of miRNA dysregulation in cancer.

title: Up-regulation of miR-190b promoted growth, invasion, migration and inhibited apoptosis of Wilms' tumor cells by repressing the PTEN expression.
abstract: Wilms' tumor (WT) is the most common malignant tumor in the children's urogenital system. MiR-190b was found to participate in the development and progression of several cancers. However, the molecular mechanism of miR-190b in WT is still unclear.



We detected the miR-190b in WT tissue samples compared to adjacent normal samples as well as in WT patients' blood sample compared to normal volunteers using qRT-PCR. With over-expression and knockdown of miR-190b in WT-derived cell line SK-NEP-1, we next studied cell proliferation, cell circle, apoptosis, invasion and migration abilities change caused by miR-190b ectopic expression. Dual-luciferase assay and Western-blot analysis were used to explain the mechanism of miR-190b in WT.



MiR-190b was over-expressed in WT tissue and blood samples compared to normal group, relatively. Up-regulation of miR-190b in SK-NEP-1 cells significantly increased the growth and decreased the apoptosis of cells, while its down-regulation reduced cell proliferation and promoted cell apoptosis of SK-NEP-1. Also, cell invasion and migration abilities were significantly improved after miR-190b over-expression. Moreover, PTEN was proved to be a direct target of miR-190b and its protein level was remarkably decreased after miR-190b up-regulation.



miR-190b over-expressed in WT and promoted cell proliferation, invasion and migration while reduced cell apoptosis of WT cells by repressing PTEN repression, which might provide a potential target for WT diagnosis and therapy.

title: MicroRNA-190b inhibits tumor cell proliferation and induces apoptosis by regulating Bcl-2 in U2OS osteosarcoma cells.
abstract: Osteosarcoma (OS) is one of the most prevalent malignancies in bone with no established therapy so far. This study was aimed to clarify the role of miR-190b in tumor cell growth of OS. The miR-190b mimic, inhibitor and miR-control were transfected into human OS U2OS cells. Then U2OS cell proliferation was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and bromodeoxyuridine (BrdU) incorporation assay. The apoptotic U2OS cells were detected by flow cytometry. Additionally, cell-cycle regulators p27, p21 and apoptosis factors B-cell lymphoma-2 (Bcl-2), Bcl-2 associated X (Bax), caspase-3 were examined by western blotting. Overexpressing miR-190b observably reduced cell viability, BrdU-positive cells (both P < 0.05) and caused strong accumulation of cell-cycle inhibitor p27 in U2OS cells compared with the miR-control, whereas the miR-190b inhibitor exerted opposite effects. Further, a marked increase of 18% rate of apoptotic cells by the overexpressing miR-190b (P < 0.01) and 4% decrease by miR-190b inhibitor (P < 0.05) were detected. The protein expressions of Bcl-2 were downregulated, Bax, pro-caspase-3 and active caspase-3 were upregulated by overexpressing miR-190b in U2OS cell line, while miR-190b inhibitor achieved opposite effects. The present study demonstrates that miR-190b inhibits tumor cell proliferation and induces apoptosis by regulating Bcl-2 in U2OS cells, which points to miR-190b as a novel oncosuppressor for OS. The identified tumor suppressive capacity of miR-190b provides novel avenues for achieving better OS therapy.

title: MicroRNA-190b confers radio-sensitivity through negative regulation of Bcl-2 in gastric cancer cells
abstract: ObjectivesTo determine the role of miR-190b in radio-sensitivity of gastric cancer (GC).ResultsIn radio-resistant GC cells, down-regulation of miR-190b and up-regulation of Bcl-2 were observed. The protein expression of Bcl-2 was negatively regulated by miR-190b. Overexpression of miR-190b significantly decreased cell viability and enhanced radio-sensitivity of GC cells. Of note, these effects of miR-190b on GC cells radio-sensitivity were abolished by Bcl-2.ConclusionmiR-190b confers radio-sensitivity of GC cells, possibly via negative regulation of Bcl-2.

title: Genetic Characteristics of Mitochondrial DNA Was Associated with Colorectal Carcinogenesis and Its Prognosis
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title: MiR-452 promotes an aggressive colorectal cancer phenotype by regulating a Wnt/β-catenin positive feedback loop
abstract: BackgroundAberrant activation of Wnt/β-catenin signaling pathway is considered to be an important issue in progression and metastasis of various human cancers, especially in colorectal cancer (CRC). MiR-452 could activate of Wnt/β-catenin signaling. But the mechanism remains unclear.MethodsThe expression of miR-452 in CRC and normal tissues was detected by real-time quantitative PCR. The effect of miR-452 on CRC growth and invasion was conducted by functional experiments in vitro and in vivo. Bioinformatics and cell luciferase function studies verified the direct regulation of miR-452 on the 3’-UTR of the GSK3β, which leads to the activation of Wnt/β-catenin signaling.ResultsMiR-452 was upregulated in CRC compared with normal tissues and was correlated with clinical significance. The luciferase reporter system studies affirmed the direct regulation of miR-452 on the 3’-UTR of the GSK3β, which activate the Wnt/β-catenin signaling. The ectopic upregulation of miR-452 significantly inhibited the expression of GSK3β and enhanced CRC proliferation and invasion in vitro and in vivo. Meanwhile, knockdown of miR-452 significantly recovered the expression of GSK3β and attenuated Wnt/β-catenin-mediated cell metastasis and proliferation. More important, T-cell factor/lymphoid enhancer factor (TCF/LEF) family of transcription factors, which are crucial downstream molecules of the Wnt/β-catenin signaling pathway was verified as a valid transcription factor of miR-452’s promoter.ConclusionsOur findings first demonstrate that miR-452-GSK3β-LEF1/TCF4 positive feedback loop induce CRC proliferation and migration.

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title: microRNA‑196b promotes cell migration and invasion by targeting FOXP2 in hepatocellular carcinoma.
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