87 research outputs found
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Speaking out about gender imbalance in invited speakers improves diversity.
Omissions of qualified women scientists from major meeting programs continue to occur despite a surge in articles indicating persistent gender-discriminatory practices in hiring and promotion, and calls for gender balance in conference organizing committees
Socs3 expression in myeloid cells modulates the pathogenesis of dextran sulfate sodium (DSS)-induced colitis
IntroductionMyeloid cells play a critical role in the pathogenesis of Inflammatory Bowel Diseases (IBDs), including Ulcerative Colitis (UC) and Crohn’s Disease (CD). Dysregulation of the JAK/STAT pathway is associated with many pathological conditions, including IBD. Suppressors Of Cytokine Signaling (SOCS) are a family of proteins that negatively regulate the JAK/STAT pathway. Our previous studies identified that mice lacking Socs3 in myeloid cells developed a hyper-activated phenotype of macrophages and neutrophils in a pre-clinical model of Multiple Sclerosis.MethodsTo better understand the function of myeloid cell Socs3 in the pathogenesis of colitis, mice with Socs3 deletion in myeloid cells (Socs3ΔLysM) were utilized in a DSS-induced colitis model.ResultsOur results indicate that Socs3 deficiency in myeloid cells leads to more severe colitis induced by DSS, which correlates with increased infiltration of monocytes and neutrophils in the colon and increased numbers of monocytes and neutrophils in the spleen. Furthermore, our results demonstrate that the expression of genes related to the pathogenesis and diagnosis of colitis such as Il1β, Lcn2, S100a8 and S100a9 were specifically enhanced in Socs3-deficient neutrophils localized to the colon and spleen. Conversely, there were no observable differences in gene expression in Ly6C+ monocytes. Depletion of neutrophils using a neutralizing antibody to Ly6G significantly improved the disease severity of DSS-induced colitis in Socs3-deficient mice.DiscussionThus, our results suggest that deficiency of Socs3 in myeloid cells exacerbates DSS-induced colitis and that Socs3 prevents overt activation of the immune system in IBD. This study may provide novel therapeutic strategies to IBD patients with hyperactivated neutrophils
MicroRNA-31 is required for astrocyte specification
Previously, we determined microRNA-31 (miR-31) is a noncoding tumor suppressive gene frequently deleted in glioblastoma (GBM); miR-31 suppresses tumor growth, in part, by limiting the activity of NF-ÎşB. Herein, we expand our previous studies by characterizing the role of miR-31 during neural precursor cell (NPC) to astrocyte differentiation. We demonstrate that miR-31 expression and activity is suppressed in NPCs by stem cell factors such as Lin28, c-Myc, SOX2 and Oct4. However, during astrocytogenesis, miR-31 is induced by STAT3 and SMAD1/5/8, which mediate astrocyte differentiation. We determined miR-31 is required for terminal astrocyte differentiation, and that the loss of miR-31 impairs this process and/or prevents astrocyte maturation. We demonstrate that miR-31 promotes astrocyte development, in part, by reducing the levels of Lin28, a stem cell factor implicated in NPC renewal. These data suggest that miR-31 deletions may disrupt astrocyte development and/or homeostasis
Loss of the Promyelocytic Leukemia Protein in Gastric Cancer: Implications for IP-10 Expression and Tumor-Infiltrating Lymphocytes
Gastric cancer is one of the most common causes of cancer-related mortality worldwide. Expression of the tumor suppressor, promyelocytic leukemia (PML) protein, is reduced or abolished in gastric carcinomas, in association with an increased level of lymphatic invasion, development of higher pTNM staging, and unfavorable prognosis. Herein, we investigated the relationship between the extent of tumor-infiltrating lymphocytes and the status of PML protein expression in advanced gastric carcinoma. We observed higher numbers of infiltrating T-cells in gastric carcinoma tissues in which PML expression was reduced or abolished, compared to tissues positive for PML. The extent of T-cell migration toward culture supernatants obtained from interferon-gamma (IFN-Îł-stimulated gastric carcinoma cell lines was additionally affected by expression of PML in vitro. Interferon-gamma-inducible protein 10 (IP-10/CXCL10) expression was increased in gastric carcinoma tissues displaying reduced PML levels. Moreover, both Pml knockout and knockdown cells displayed enhanced IP-10 mRNA and protein expression in the presence of IFN-Îł. PML knockdown increased IFN-Îł-mediated Signal Transducer and Activator of Transcription-1 (STAT-1) binding to the IP-10 promoter, resulting in elevated transcription of the IP-10 gene. Conversely, PML IV protein expression suppressed IP-10 promoter activation. Based on these results, we propose that loss of PML protein expression in gastric cancer cells contributes to increased IP-10 transcription via enhancement of STAT-1 activity, which, in turn, promotes lymphocyte trafficking within tumor regions
The Immune Regulatory Role of Protein Kinase CK2 and Its Implications for Treatment of Cancer
Protein Kinase CK2, a constitutively active serine/threonine kinase, fulfills its functions via phosphorylating hundreds of proteins in nearly all cells. It regulates a variety of cellular signaling pathways and contributes to cell survival, proliferation and inflammation. CK2 has been implicated in the pathogenesis of hematologic and solid cancers. Recent data have documented that CK2 has unique functions in both innate and adaptive immune cells. In this article, we review aspects of CK2 biology, functions of the major innate and adaptive immune cells, and how CK2 regulates the function of immune cells. Finally, we provide perspectives on how CK2 effects in immune cells, particularly T-cells, may impact the treatment of cancers via targeting CK2
Viral Exploitation of Host SOCS Protein Functionsâ–ż
Over the past decade, a family of host proteins known as suppressors of cytokine signaling (SOCS) have emerged as frequent targets of viral exploitation. Under physiologic circumstances, SOCS proteins negatively regulate inflammatory signaling pathways by facilitating ubiquitination and proteosomal degradation of pathway machinery. Their expression is tightly regulated to prevent excessive inflammation while maintaining protective antipathogenic responses. Numerous viruses, however, have developed mechanisms to induce robust host SOCS protein expression following infection, essentially “hijacking” SOCS function to promote virus survival. To date, SOCS proteins have been shown to inhibit protective antiviral signaling pathways, allowing viruses to evade the host immune response, and to ubiquitinate viral proteins, facilitating intracellular viral trafficking and progeny virus assembly. Importantly, manipulation of SOCS proteins not only facilitates progression of the viral life cycle but also powerfully shapes the presentation of viral disease. SOCS proteins can define host susceptibility to infection, contribute to peripheral disease manifestations such as immune dysfunction and cancer, and even modify the efficacy of therapeutic interventions. Looking toward the future, it is clear that a better understanding of the role of SOCS proteins in viral diseases will be essential in our struggle to modulate and even eliminate the pathogenic effects of viruses on the host
IL-4-Activated STAT-6 Inhibits IFN-Îł-Induced CD40 Gene Expression in Macrophages/Microglia
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