miR-24-3p stimulates migration, invasion and proliferation of prostate cancer cells by targeting suppressor of cytokine signaling 6
INTERNATIONAL JOURNAL OF CLINICAL AND EXPERIMENTAL PATHOLOGY
Authors: Lin, Yang; Cao, Huifang; Tian, Yuxin; Yang, Xinping; Zhou, Changdong; Zhang, Qifu
Abstract
Prostate cancer is among the most widespread malignancies affecting men in the world. Its aggressive evolution has been associated with altered expression of suppressor of cytokine signaling 6 (SOCS6) but very little is known about the mechanism by which this alteration occurs. The purpose of this study was to explore the role of SOCS6 in prostate cancer cells and the involvement of its regulating microRNA (miR), miR-24-3p. Prostate cancer cell lines were used to determine the transcription level of miR-24-3p and SOCS6 by quantitative reverse-transcriptase-polymerase chain reaction (qRT-PCR) and Western blot. Cell proliferation and cell migration assays were done- to determine the effect of miR-24-3p mimics and inhibitors on cell proliferation, invasion and migration. Luciferase reporter assay with SOCS6 3'-UTR was performed to confirm the control of SOCS6 expression by the miR. The results showed that miR-24-3p was up-regulated in prostate cancer cells whereas SOCS6 protein was downregulated. Overexpression of miR-24-3p in prostate cancer cells promoted cell proliferation, inhibited apoptosis, and increased cell migration and invasion. Luciferase reporter assays showed that SOCS6 is a direct target of its negative regulator miR-24-3p and overexpression of SOCS6 reverses the effects of miR-24-3p on the metastatic phenotype of prostate cancer cells. These results show case miR-24-3p up-regulation in prostate cancer and a mechanism for inhibition of SOCS6 expression. Thus, the miR-24-3p/SOCS6 pathway could be a relevant avenue for prostate cancer treatment.
Downregulation of microRNA-431 by human interferon-beta inhibits viability of medulloblastoma and glioblastoma cells via upregulation of SOCS6
INTERNATIONAL JOURNAL OF ONCOLOGY
Authors: Tanaka, Takeshi; Arai, Makoto; Jiang, Xia; Sugaya, Shigeru; Kanda, Tatsuo; Fujii, Katsunori; Kita, Kazuko; Sugita, Katsuo; Imazeki, Fumio; Miyashita, Toshiyuki; Kaneda, Atsushi; Yokosuka, Osamu
Abstract
miRNAs are small non-coding RNAs that inhibit gene expression by cleaving or hindering the translation of target mRNAs. In this study, we focused on miR-431, which mediated inhibition of cell viability by human interferon-beta (HuIFN-beta). We aimed to demonstrate an antineoplastic effect of HuIFN-beta via miR-431 expression against medulloblastoma and glioblastoma, because HuIFN-beta is frequently used in adjuvant therapy of these tumors. Addition of HuIFN-beta to medulloblastoma and glioblastoma cells reduced viability, significantly decreased miR-431 expression, upregulated expression of SOCS6 (putative miR-431 target genes) and inhibited Janus kinase (JAK) 1 and signal transducer and activator of transcription (STAT) 2. The mitogen-activated protein kinase (MAPK) pathway, but not the phosphoinositide 3-kinase (PI3K)-Akt pathway, was downregulated in medulloblastoma cells, whereas the PI3K-Akt pathway, but not the MAPK pathway, was downregulated in glioblastoma cells. Addition of HuIFN-beta and transient transfection with miR-431 to medulloblastoma and glioblastoma cells did not reduce viability, downregulated expression of SOCS6, and concomitantly activated the JAK1 and STAT2. We propose that, in medulloblastoma and glioblastoma cells, HuIFN-beta decreases miR-431 expression and upregulates SOCS6 expression, and consequently inhibit cell proliferation by suppressing the JAK-STAT signaling pathway.