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Type 2 diabetes is preceded by a defective insulin response, yet our knowledge of the precise mechanisms is incomplete. Here, we investigate how insulin resistance alters skeletal muscle signaling and how exercise partially counteracts this effect. We measured parallel phenotypes and phosphoproteomes of insulin-resistant (IR) and insulin-sensitive (IS) men as they responded to exercise and insulin (n = 19, 114 biopsies), quantifying over 12,000 phosphopeptides in each biopsy. Insulin resistance involves selective and time-dependent alterations to signaling, including reduced insulin-stimulated mTORC1 and non-canonical signaling responses. Prior exercise promotes insulin sensitivity even in IR individuals by "priming" a portion of insulin signaling prior to insulin infusion. This includes MINDY1 S441, which we show is an AKT substrate. We found that MINDY1 knockdown enhances insulin-stimulated glucose uptake in rat myotubes. This work delineates the signaling alterations in IR skeletal muscle and identifies MINDY1 as a regulator of insulin action. [Display omitted] • Insulin resistance primarily alters non-canonical insulin signaling • mTORC1 substrates were most defective in insulin resistance • Exercise counteracts insulin signaling defects, including MINDY1 S441 • MINDY1 negatively regulates rat myotube insulin action, and S441 is an AKT substrate Needham et al. studied the impact of insulin resistance on signaling responses to insulin and exercise in human skeletal muscle biopsies, including MINDY1 phosphorylation, which was lower in insulin resistance and primed by prior exercise. Their experiments show that MINDY1 is a target of AKT and negatively regulates insulin action. [ABSTRACT FROM AUTHOR]

Background/Aim: Leukaemia is a malignant disease of blood cells found in the bone marrow, which can be divided into acute lymphocytic leukaemia and myelocytic leukaemia. Current management of acute leukaemia still uses chemo therapy as the main therapy but has many side effects, therefore a new approach is needed to identify genetic factors involved in leukaemia. The aim of this study was to investigate gene variations that have potential pathogenic properties in leukaemia. Methods: This study used genome-wide association study (GWAS) data obtained from the National Human Genome Research Institute (NHGRI) to search for genomic variants associated with leukaemia. The data was then screened using SNPnexus to detect potentially protein-damaging variants. Furthermore, the gene expression of these variants was analysed using the GTEx portal. Results: Of the 2115 genomic variants found, four were deleterious, namely rs12140153, rs140386498, rs757110 and rs2066827, representing four different genes, namely PATJ, MINDY1, ABCC8 and CDKN1B. Alterations in the expression of PATJ, MINDY1, CDKN1B and ABCC8 genes affect the brain and leukaemia development. PATJ maintains brain cell integrity, MINDY1 regulates gene expression, CDKN1B controls the cell cycle and ABCC8 regulates glucose levels. Their deregulation is associated with neurological dysfunction and leukaemia. Variation in allele frequencies showed differences between continents, with rs757110 and rs2066827 having higher expression than rs12140153 and rs140386498. Variant gene expression also varied between tissues, with rs757110 and rs2066827 showing higher expression than rs12140153 and rs140386498. Conclusion: This study successfully identified four genomic variants by harnessing a genomic and bioinformatic database, which are associated with leukemia and demonstrated variations in gene distribution and expression across different populations and tissues. [ABSTRACT FROM AUTHOR]

The novel deubiquitinase enzyme, motif interacting with ubiquitin-containing novel DUB family-1 (MINDY1), is highly expressed in liver cancer tissues and plays a crucial role in maintaining the stemness of liver cancer cells. Programmed death ligand-1 (PD-L1) is an immunosuppressive molecule overexpressed by tumour cells. The potential role of MINDY1 in inhibiting the stemness of liver cancer cells by deubiquitinating PD-L1 has not yet been reported. To investigate the mechanism by which MINDY1 mediates immune escape in liver cancer through the regulation of PD-L1 ubiquitination, we examined the expression levels of MINDY1 and PD-L1 in liver cancer and adjacent tissues from 50 hepatocellular carcinoma (HCC) patients using protein imprinting and immunohistochemistry. We analyzed the relationship between the expression levels of MINDY1 and PD-L1 in liver cancer tissues and their correlation with the 5-year tumor-free survival rates of patients. Subsequently, MINDY1 expression was knocked down in Huh7 cells using small interfering RNA (siRNA) interference or upregulated through transfection with a MINDY1 overexpression plasmid. The effects of MINDY1 knockdown or overexpression on the proliferation, apoptosis, migration, and invasion of HCC cells, as well as the regulation of PD-L1 binding and ubiquitination, were assessed. The 5-year tumor-free survival rates were significantly lower in both the high MINDY1 expression group and the high PD-L1 expression group (χ2 = 4.919 and 13.158, respectively). A significant difference in survival was observed between the high and low MINDY1 expression groups (χ2= 27.415). MINDY1 was found to directly interact with PD-L1, with MINDY1 gene knockdown promoting PD-L1 ubiquitination and MINDY1 overexpression inhibiting PD-L1 ubiquitination. All comparisons yielded statistically significant results (P < 0.05). In conclusion, MINDY1 inhibits the malignant progression of liver cancer by inhibiting PD-L1 ubiquitination and mediating immune escape.

Abstract Background Bladder cancer is one of the most commonly diagnosed urological malignant tumor. The Hippo tumor suppressor pathway is highly conserved in mammals and plays an important role in carcinogenesis. YAP is one of major key effectors of the Hippo pathway. However, the mechanism supporting abnormal YAP expression in bladder cancer remains to be characterized. Methods Western blot was used to measure the expression of MINDY1 and YAP, while the YAP target genes were measured by real-time PCR. CCK8 assay was used to detect the cell viability. The xeno-graft tumor model was used for in vivo study. Protein stability assay was used to detect YAP protein degradation. Immuno-precipitation assay was used to detect the interaction domain between MINDY1 and YAP. The ubiquitin-based Immuno-precipitation assays were used to detect the specific ubiquitination manner happened on YAP. Results In the present study, we identified MINDY1, a DUB enzyme in the motif interacting with ubiquitin-containing novel DUB family, as a bona fide deubiquitylase of YAP in bladder cancer. MINDY1 was shown to interact with, deubiquitylate, and stabilize YAP in a deubiquitylation activity-dependent manner. MINDY1 depletion significantly decreased bladder cancer cell proliferation. The effects induced by MINDY1 depletion could be rescued by further YAP overexpression. Depletion of MINDY1 decreased the YAP protein level and the expression of YAP/TEAD target genes in bladder cancer, including CTGF, ANKRD1 and CYR61. Conclusion In general, our findings establish a previously undocumented catalytic role for MINDY1 as a deubiquitinating enzyme of YAP and provides a possible target for the therapy of bladder cancer.

Background: Bladder cancer is one of the most commonly diagnosed urological malignant tumor. The Hippo tumor suppressor pathway is highly conserved in mammals and plays an important role in carcinogenesis. YAP is one of major key effectors of the Hippo pathway. However, the mechanism supporting abnormal YAP expression in bladder cancer remains to be characterized. Methods: Western blot was used to measure the expression of MINDY1 and YAP, while the YAP target genes were measured by real-time PCR. CCK8 assay was used to detect the cell viability. The xeno-graft tumor model was used for in vivo study. Protein stability assay was used to detect YAP protein degradation. Immuno-precipitation assay was used to detect the interaction domain between MINDY1 and YAP. The ubiquitin-based Immuno-precipitation assays were used to detect the specific ubiquitination manner happened on YAP. Results: In the present study, we identified MINDY1, a DUB enzyme in the motif interacting with ubiquitin-containing novel DUB family, as a bona fide deubiquitylase of YAP in bladder cancer. MINDY1 was shown to interact with, deubiquitylate, and stabilize YAP in a deubiquitylation activity-dependent manner. MINDY1 depletion significantly decreased bladder cancer cell proliferation. The effects induced by MINDY1 depletion could be rescued by further YAP overexpression. Depletion of MINDY1 decreased the YAP protein level and the expression of YAP/TEAD target genes in bladder cancer, including CTGF, ANKRD1 and CYR61. Conclusion: In general, our findings establish a previously undocumented catalytic role for MINDY1 as a deubiquitinating enzyme of YAP and provides a possible target for the therapy of bladder cancer. [ABSTRACT FROM AUTHOR]

Objective: To explore the key deubiquitinating enzymes that maintain the stemness of liver cancer stem cells and provide new ideas for targeted liver cancer therapy. Methods: The high-throughput CRISPR screening technology was used to screen the deubiquitinating enzymes that maintain the stemness of liver cancer stem cells. RT-qPCR and Western blot were used to analyze gene expression levels. Stemness of liver cancer cells was detected by spheroid-formation and soft agar colony formation assays. Tumor growth in nude mice was detected by subcutaneous tumor-bearing experiments. Bioinformatics and clinical samples were examined for the clinical significance of target genes. Results: MINDY1 was highly expressed in liver cancer stem cells. The expression of stem markers, the self-renewal ability of cells, and the growth of transplanted tumors were significantly reduced and inhibited after knocking out MINDY1, and its mechanism of action may be related to the regulation of the Wnt signaling pathway. The expression level of MINDY1 was higher in liver cancer tissues than that in adjacent tumors, which was closely related to tumor progression, and its high expression was an independent risk factor for a poor prognosis of liver cancer. Conclusion: The deubiquitinating enzyme MINDY1 promotes stemness in liver cancer cells and is one of the independent predictors of poor prognosis in liver cancer.

Embryonic stem cells have the ability to self-renew or differentiate and these processes are under tight control. We previously reported that the polyamine regulator AMD1 is critical for embryonic stem cell self-renewal. The polyamines putrescine, spermidine, and spermine are essential organic cations that play a role in a wide array of cellular processes. Here, we explore the essential role of the polyamines in the promotion of self-renewal and identify a new stem cell regulator that acts downstream of the polyamines: MINDY1. MINDY1 protein levels are high in embryonic stem cells (ESCs) and are dependent on high polyamine levels. Overexpression of MINDY1 can promote ESC self-renewal in the absence of the usually essential cytokine Leukemia Inhibitory Factor (LIF). MINDY1 protein is prenylated and this modification is required for its ability to promote self-renewal. We go on to show that Mindy1 RNA is targeted for repression by mir-710 during Neural Precursor cell differentiation. Taken together, these data demonstrate that high polyamine levels are required for ESC self-renewal and that they function, in part, through promotion of high MINDY1 levels. Stem Cells 2018;36:1170-1178., (© 2018 The Authors Stem Cells published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.)