MicroRNA-494-3p Exacerbates Renal Epithelial Cell Dysfunction by Targeting SOCS6 under High Glucose Treatment.

BACKGROUND: Diabetic nephropathy is a common complication of the kidneys induced by diabetes and is the main cause of end-stage renal disease. MicroRNA-494-3p was reported to be upregulated in renal tissues collected from db/db mice, but its specific role in diabetic nephropathy was still unclear. This study aimed to explore the effect of miR-494-3p on renal fibrosis using an in vitro cell model of diabetic nephropathy. METHODS: After human renal tubular epithelial cells (HK-2) were treated with high glucose (HG), the viability and apoptosis of cells were examined by CCK-8 assays and flow cytometry analyses. Additionally, protein levels of fibronectin, collagen I, collagen III, collagen IV, and epithelial-mesenchymal transition (EMT) markers in HG-induced HK-2 cells were quantified by Western blotting. miR-494-3p expression in HK-2 cells was detected by reverse-transcription quantitative polymerase chain reaction. The binding relation between miR-494-3p and the messenger RNA suppressor of cytokine signaling 6 (SOCS6) was detected by luciferase reporter assays. RESULTS: HG reduced cell viability and enhanced cell apoptosis in a time- or concentration-dependent manner. Additionally, HG induced collagen accumulation and triggered the EMT process. miR-494-3p was upregulated in HG-treated HK-2 cells. miR-494-3p inhibition alleviated HG-induced cell dysfunction. Mechanistically, miR-494-3p bound with SOCS6 and negatively regulated SOCS6 expression. Moreover, silencing SOCS6 rescued the suppressive effect of miR-499-5p inhibition on HG-induced cell dysfunction. CONCLUSION: miR-494-3p aggravates renal fibrosis, EMT process, and cell apoptosis by targeting SOCS6, suggesting that the miR-494-3p/SOCS6 axis may become a potential strategy for the treatment of diabetic nephropathy.

Inhibition of miR-1298-5p attenuates sepsis lung injury by targeting SOCS6.

Sepsis is one of the leading causes of morbidity and mortality and a major cause of acute lung injury (ALI). carried by exosomes play a role in a variety of diseases. However,there are not many studies of exosomal miRNAs in sepsis and sepsis lung injury.miR-1298-5p and suppressor of cytokine signaling 6 (SOCS6) were silenced or overexpressed in human bronchial epithelial cells (BEAS-2B). PKH-67 Dye was used to trace exosome endocytosis. Cell permeability was evaluated by measuring trans-epithelial electrical resistance (TEER) and FITC dextran flux. ELISA kits were used for cytokine detection. Quantitative RT-PCR and western blots were used to evaluate gene expression. miR-1298-5p was elevated in exosomes from patients with sepsis lung injury (Sepsis_exo). Treatment of BEAS-2B cells using Sepsis_exo significantly inhibited cell proliferation, and induced cell permeability and inflammatory response. miR-1298-5p directly targeted SOCS6. Overexpressing SOCS6 reversed miR-1298-5p-induced cell permeability and inflammatory response. Inhibition of STAT3 blocked SOCS6-silencing caused significant increase of cell permeability and inflammation. Exosomes isolated from patients of sepsis lung injury increased cell permeability and inflammatory response in BEAS-2B cells through exosomal miR-1298-5p which targeted SOCS6 via STAT3 pathway. The findings highlight the importance of miR-1298-5p/SOCS6/STAT3 axis in sepsis lung injury and provide new insights into therapeutic strategies for sepsis lung injury.

Phosphorylation regulates cullin-based ubiquitination in tumorigenesis.

Cullin-RING ligases (CRLs) recognize and interact with substrates for ubiquitination and degradation, and can be targeted for disease treatment when the abnormal expression of substrates involves pathologic processes. Phosphorylation, either of substrates or receptors of CRLs, can alter their interaction. Phosphorylation-dependent ubiquitination and proteasome degradation influence various cellular processes and can contribute to the occurrence of various diseases, most often tumorigenesis. These processes have the potential to be used for tumor intervention through the regulation of the activities of related kinases, along with the regulation of the stability of specific oncoproteins and tumor suppressors. This review describes the mechanisms and biological functions of crosstalk between phosphorylation and ubiquitination, and most importantly its influence on tumorigenesis, to provide new directions and strategies for tumor therapy.

Computationally predicted SARS-COV-2 encoded microRNAs target NFKB, JAK/STAT and TGFB signaling pathways.

Recently an outbreak that emerged in Wuhan, China in December 2019, spread to the whole world in a short time and killed >1,410,000 people. It was determined that a new type of beta coronavirus called severe acute respiratory disease coronavirus type 2 (SARS-CoV-2) was causative agent of this outbreak and the disease caused by the virus was named as coronavirus disease 19 (COVID19). Despite the information obtained from the viral genome structure, many aspects of the virus-host interactions during infection is still unknown. In this study we aimed to identify SARS-CoV-2 encoded microRNAs and their cellular targets. We applied a computational method to predict miRNAs encoded by SARS-CoV-2 along with their putative targets in humans. Targets of predicted miRNAs were clustered into groups based on their biological processes, molecular function, and cellular compartments using GO and PANTHER. By using KEGG pathway enrichment analysis top pathways were identified. Finally, we have constructed an integrative pathway network analysis with target genes. We identified 40 SARS-CoV-2 miRNAs and their regulated targets. Our analysis showed that targeted genes including NFKB1, NFKBIE, JAK1-2, STAT3-4, STAT5B, STAT6, SOCS1-6, IL2, IL8, IL10, IL17, TGFBR1-2, SMAD2-4, HDAC1-6 and JARID1A-C, JARID2 play important roles in NFKB, JAK/STAT and TGFB signaling pathways as well as cells' epigenetic regulation pathways. Our results may help to understand virus-host interaction and the role of viral miRNAs during SARS-CoV-2 infection. As there is no current drug and effective treatment available for COVID19, it may also help to develop new treatment strategies.

CgSOCS6 negatively regulates the expression of CgIL17s and CgDefh1 in the pacific oyster Crassostrea gigas.

As a family of negatively feedback regulating factors, the suppressor of cytokine signaling (SOCS) can depress cytokine signal transduction, and eventually modulate growth, development, differentiation, and immune response. In the present study, a SOCS homologue (designated as CgSOCS6) was identified from oyster Crassostrea gigas. The open reading frame of CgSOCS6 cDNA was of 1167 bp encoding a peptide of 388 amino acid residues with a central Src homology 2 (SH2) domain, a conserved C-terminal SOCS box, and a nucleus localization sequence (NLS) in its N-terminus. The deduced amino acid sequence of CgSOCS6 shared 37.9-45.5% similarity with other SOCS6/7 family members. In the unrooted phylogenetic tree, CgSOCS6 was clustered with EsSOCS6 from Chinese mitten crab Eriocheir sinensis and assigned into the SOCS6/7 group. The mRNA transcripts of CgSOCS6 were constitutively distributed in all the tested tissues, with the highest level in hemocytes. After lipopolysaccharide (LPS) stimulation, the mRNA expression of CgSOCS6 in hemocytes was significantly up-regulated to the highest level at 6 h (8.48-fold compared to the control group, p < 0.01), and then kept at a relatively higher level from 12 h to 72 h. CgSOCS6 protein could be translocated into the hemocyte nucleus after LPS stimulation. The mRNA expressions of interleukin 17-4 (CgIL17-4), CgIL17-5, and defensin (CgDefh1) in the hemocytes of CgSOCS6-knockdown oysters increased significantly (2.55-fold, 2.68-fold, 4.68-fold of that in EGFP-RNAi oysters, p < 0.05, p < 0.05, p < 0.001, respectively) after LPS stimulation. These findings suggested that CgSOCS6 was involved in the oyster immune response by regulating the expressions of CgIL17-4, CgIL17-5, and CgDefh1.

miR-494 inhibits cervical cancer cell proliferation through upregulation of SOCS6 expression.

It is unclear how microRNA (miR)-494 inhibits the proliferation of cervical cancer cells by altering the expression of SOCS6. Therefore, the present study aimed to investigate the molecular mechanism underlying miR-494 regulation of suppressor of cytokine signaling 6 (SOCS6) in human cervical cancer samples and the human cervical cancer HeLa cell line. The expression of miR-494 was determined using reverse transcription-quantitative polymerase chain reaction. In addition, TargetScan was used to predict miR-494 target genes and the luciferase reporter assay was used to determine whether SOCS6 was a direct target of miR-494. The results of the present study demonstrated that compared with the cervical intraepithelial neoplasia and normal cervical tissues, the miR-494 expression level in cervical cancer samples was significantly decreased (P<0.01). In addition, compared with normal cervical tissue, miR-494 expression level was significantly decreased in cervical intraepithelial lesions (P<0.05). Furthermore, the expression of miR-494 was associated with patients with or without lymph node metastasis, clinical stage and depth of stromal invasion (P<0.01); however, miR-494 expression was not identified to be associated with age, tumor size and menopausal status (P>0.05). Transfection of a miR-494 mimic significantly increased the expression level of miR-494 in HeLa cells (P<0.01), and anti-miR-494 transfection decreased the expression of miR-494 (P<0.01). An MTT proliferation assay and Boyden chamber invasion ability assay revealed that miR-494 mimic transfection significantly inhibited the proliferation, and invasion ability of HeLa cells (P<0.01), whereas anti-miR-494 transfection significantly increased the proliferation and invasion ability (P<0.05). SOCS6 was predicted, using bioinformatics, to be the target gene of miR-494 and this was validated using a luciferase reporter assay. Western blot analysis revealed that transfection of miR-494 significantly increased the expression of SOCS6 in HeLa cells, and transfection of anti-miR-494 significantly decreased the expression of SOCS6. Therefore, the results of the present study demonstrated that miR-494 expression in cervical cancer was significantly decreased. Exhibiting a decreased expression level of miR-494 may result in enhanced proliferative and invasive abilities of HeLa cell, thus contributing to the occurrence, and development of cervical cancer.

SOCS6 Functions as a Tumor Suppressor by Inducing Apoptosis and Inhibiting Angiogenesis in Human Prostate Cancer.

BACKGROUND: Our previous studies revealed that the downregulation of Suppressor of cytokine signaling 6 (SOCS6) was correlated with malignant progression of human prostate cancer (PCa). AIMS: In the current study, we aimed to investigate the tumor suppressive roles of SOCS6 and the underlying mechanisms in PCa. METHODS: SOCS6 expression in PCa and non-cancerous prostate tissues was compared by immunohistochemistry. Statistical associations of SOCS6 expression with various clinicopathological features and patients prognosis were evaluated. In addition, we investigated SOCS6's functions by overexpressing it in vitro (cell apoptosis, migration and invasion assays) and in vivo (tumor formation, angiogenesis and apoptosis). Moreover, SOCS6-regulated genes were identified by nextgeneration RNA-sequencing analysis, followed by pathway enrichment analysis and in vitro experimental validation. RESULTS: SOCS6 downregulation was significantly associated with advanced clinical stage (P=0.029) and positive lymph node metastasis (P=0.013) in PCa patients. We also identified SOCS6 as an independent prognostic factor for disease-free survival in PCa patients (P=0.045). Moreover, overexpression of SOCS6 inhibited PCa cell invasion, migration, tumor xenografts growth and angiogenesis, but induced PCa cell apoptosis (P values <0.05). Mechanically, we revealed that SOCS6 expression may induce cell apoptosis coincident with down-regulation of Bcl2 and Hspa1a, and may suppress tumor angiogenesis with downregulation of F7, Fak3 and Frzb. CONCLUSION: These findings suggest that the reduced expression of SOCS6 may be predictive of unfavorable prognosis in PCa. Thus, SOCS6 may serve as a tumor suppressor and a novel therapeutic target for this cancer.