Nuclear receptor estrogen-related receptor gamma suppresses colorectal cancer aggressiveness by regulating Wnt/ß-catenin signaling.

Colorectal cancer (CRC) is the predominant cause of cancer-related death worldwide, because of the lack of effective therapeutic targets. Estrogen-related receptor gamma (ESRRG), which belongs to the family of nuclear receptors, functions as an important element regulating gene transcription. In our report, we identified ESRRG as a potential tumor suppressor. The decreased level of ESRRG was initially observed in CRC and was highly associated with a poor prognosis. ESRRG overexpression abrogated cell growth and metastasis in vitro and in vivo. Mechanistically, ESRRG repressed the epithelial-to-mesenchymal transition process and antagonized Wnt signaling by regulating ß-catenin degradation. In addition, significant ESRRG hypermethylation was found in CRC and inversely correlated with its expression. Consistently, the expression of ESRRG was induced after treatment with DNA demethylating agent 5-aza-2'-deoxycytidine. Taken together, these findings define a tumor-suppressive role of ESRRG in CRC, providing a potential novel therapeutic approach for this cancer.

Dysfunction of peripheral regulatory T cells predicts lung injury after cardiopulmonary bypass.

Lung injury caused by cardiopulmonary bypass (CPB) increases the mortality after cardiac surgery. Previous studies have shown that regulatory T cells (Tregs) play a protective role during CPB, but the correlation between Tregs and CPB-induced lung injury remains unclear. Here, we conducted a prospective study about Treg cells in patient receiving CPB. Treg cells were collected from patients before the CPB operation (pre-CPB Tregs), and the effect of pre-CPB Tregs on the occurrence of CPB-induced lung injury was evaluated. Data showed that the baseline level of Treg cells in peripheral blood were lower in patients who developed lung injury after CPB, compared to those who did not develop lung injury after CPB. Function analyses revealed that pre-CPB Tregs from CPB-induced lung injury patients presented decreased ability in suppressing the proliferation and IFN-γ production of CD4 and CD8 T cell. Also, pre-surgery levels of TGF- ß and IL-10 were markedly lower in lung injury patients than in non-lung injury patients. In addition, PD-1 and Tim-3 expression on pre-CPB Tregs were significantly lower in CPB-induced lung injury patients than the CPB patients without lung injury. Above all, we found impaired peripheral Treg responses in CPB-induced lung injury patients, indicating a potential role of Treg cells in the early diagnosis of CPB-induced lung injury.

Identification and functional analysis of lncRNAs and mRNAs between tumorigenesis and metastasis in CRC.

The role of long non-coding RNAs (lncRNAs) in colorectal cancer (CRC) tumorigenesis and metastasis remains poorly characterized. The aim of this study was to identify novel lncRNAs and their functions in CRC progression. Through microarray analysis of paired normal colorectal mucosa (NM), primary tumor (PT), and metastatic lymph node (MLN) tissues, lncRNA and mRNA expression patterns were identified. Further bioinformatic analyses were performed to compare the biological functions of lncRNAs between tumorigenesis and metastasis of CRC, which was further verified by TCGA-COAD and GSE82236. The expression of lncRNA MIR29B2CHG93 in paired CRC tissues was detected in a cohort of CRC patients. The effects of lncRNA MIR29B2CHG93 on proliferation, migration, and invasion were determined by in vitro experiments. We found that tumorigenesis-associated lncRNAs predominantly participated in the regulation of the EMT/P53/PI3K-Akt/KRAS signaling pathway as well as the processes related to cell cycle and cell mitosis, while metastasis-associated lncRNAs mainly regulated blood vessel morphogenesis and immune-related biological processes. Compared to the TCGA and GSE datasets, seven tumorigenesis-associated lncRNAs and eight metastasis-associated lncRNAs were identified. LncRNA MIR29B2CHG93 knockdown remarkably suppressed tumor growth and metastasis in vitro, which acted as a tumor promoter in CRC. The lncRNA MIR29B2CHG93 was significantly upregulated in CRC tissues and was indicator of unfavorable clinical outcome in CRC. These results revealed novel lncRNAs that provide new insights for an in-depth understanding of CRC progression. In particular, this study identified a novel lncRNA MIR29B2CHG93 in CRC progression, which might be a potential biomarker for diagnosis, prognosis and metastasis-prediction in CRC.

FLRT2 functions as Tumor Suppressor gene inactivated by promoter methylation in Colorectal Cancer.

Colorectal cancer (CRC) is a leading cause of cancer death worldwide. Epigenetic alterations, especially DNA methylation, contribute to the initiation and progression of CRC. To identify novel methylated tumor suppressors in CRC, MethylRAD-Seq screening was performed. As the result, FLRT2 was found to be preferentially methylated. In the present study, we aimed to elucidate the epigenetic regulations and biological functions of FLRT2 in CRC. Significant FLRT2 hypermethylation was initially confirmed in CRC samples and cell lines. Meanwhile, downregulated expression of FLRT2 was observed in CRC, which is probably attributed to promoter methylation of FLRT2. Consistently, the expression of FLRT2 was restored after treatment with DNA demethylating agent 5-AZA. FLRT2 overexpression resulted in impaired cell viability and colony formation. Additionally, FLRT2 overexpression led to a reduction in cell migration and cell invasion. Furthermore, we also observed that FLRT2 induced cell cycle arrest. Mechanistically, these effects were associated with the downregulation of phosphor-AKT, phosphor-ERK, CDK2, Cyclin A, and MMP2, and upregulation of P21. Taken together, these results define a tumor-suppressor role of FLRT2 with epigenetic silencing in the pathogenesis of CRC. Moreover, FLRT2 promoter methylation may be a useful epigenetic biomarker for the prevention and treatment of CRC.

Correction to: Exosomes derived from atorvastatin-modified bone marrow dendritic cells ameliorate experimental autoimmune myasthenia gravis by up-regulated levels of IDO/Treg and partly dependent on FasL/Fas pathway.

After the publication of the original article [1], it came to the authors' attention that there was an error in the originally published version of Fig. 5b. The image of CD4+CD25+ T cells of the statin-Dex group was unintentionally replaced with the image of CD4+CD25+ T cells from the control group. The correct version of Fig. 5b is published in this Erratum.

Secretory Clusterin Mediates Oxaliplatin Resistance via the Gadd45a/PI3K/Akt Signaling Pathway in Hepatocellular Carcinoma.

Purpose: Systemic therapy has often been used for patients with advanced hepatocellular carcinoma (HCC). However, due to drug resistance, the use of cytotoxic chemotherapy in the treatment of patients with advanced HCC has typically demonstrated low response rates. Secretory clusterin (sCLU) is expressed in aggressive late-stage tumors and associated with resistance to chemotherapy, including that in HCC cases. The present research aimed to investigate the biological role of sCLU in HCC. Methods: sCLU expression in HCC and normal tissues was examined using immunohistochemical staining, followed by analysis of the correlation between sCLU expression and clinical indicators. In addition, the role and internal mechanism of sCLU in cell proliferation and apoptosis were investigated in HCC cells. Results: sCLU expression was significantly upregulated in HCC tissues; and was associated with histological grade and poor overall survival. The levels of sCLU were significantly increased in Bel7402, SMMC7721 and resistant HCC cells (Bel7404-OR). Inhibiting the activity of sCLU enhanced the chemosensitivity of Bel7402 and SMMC7721 cells. Downregulation of sCLU could increase the expression of Gadd45a in HCC cells. Overexpression of sCLU contributed to drug resistance in Bel7402, SMMC7721 and Bel7404-OR cells; whereas, overexpression of Gadd45a alone overcame drug resistance in the cells above. No significant expression changes of sCLU and Gadd45a were observed in HCC cells after the interference of a selective inhibitor of the PI3K/Akt signaling pathway. However, regulation of the expression of Gadd45a could influence the phosphorylation level of Akt; and further regulate the expression of Bcl-2 and Bax proteins involved in the mitochondrial apoptosis pathways. Conclusions: The results demonstrate that sCLU/Gadd45a/PI3K/Akt signaling represents a novel pathway that could regulate drug resistance in a one-way manner in HCC cells.

Enhanced glycolysis contributes to the pathogenesis of experimental autoimmune neuritis.

BACKGROUND: With the recognition of the key roles of cellular metabolism in immunity, targeting metabolic pathway becomes a new strategy for autoimmune disease treatment. Guillain-Barré syndrome (GBS) is an acute immune-mediated inflammatory demyelinating disease of the peripheral nervous system, characterized by inflammatory cell infiltration. These inflammatory cells, including activated macrophages, Th1 cells, and Th17 cells, generally undergo metabolic reprogramming and rely mainly on glycolysis to exert functions. This study aimed to explore whether enhanced glycolysis contributed to the pathogenesis of experimental autoimmune neuritis (EAN), a classic model of GBS. METHODS: Preventive and therapeutic treatments with glycolysis inhibitor, 2-deoxy-D-glucose (2-DG), were applied to EAN rats. The effects of treatments were determined by clinical scoring, weighting, and tissue examination. Flow cytometry and ELISA were used to evaluate T cell differentiation, autoantibody level, and macrophage functions in vivo and in vitro. RESULTS: Glycolysis inhibition with 2-DG not only inhibited the initiation, but also prevented the progression of EAN, evidenced by the improved clinical scores, weight loss, inflammatory cell infiltration, and demyelination of sciatic nerves. 2-DG inhibited the differentiation of Th1, Th17, and Tfh cells but enhanced Treg cell development, accompanied with reduced autoantibody secretion. Further experiments in vitro proved glycolysis inhibition decreased the nitric oxide production and phagocytosis of macrophages and suppressed the maturation of dendritic cells (DC). CONCLUSION: The effects of glycolysis inhibition on both innate and adaptive immune responses and the alleviation of animal clinical symptoms indicated that enhanced glycolysis contributed to the pathogenesis of EAN. Glycolysis inhibition may be a new therapy for GBS.

Toll-like receptor 9 antagonist suppresses humoral immunity in experimental autoimmune myasthenia gravis.

Recent studies have demonstrated the important role of toll-like receptor 9 (TLR9) signalling in autoimmune diseases, but its role in myasthenia gravis (MG) has not been fully established. We show herein that blocking TLR9 signalling via the suppressive oligodeoxynucleotide (ODN) H154 alleviated the symptoms of experimental autoimmune myasthenia gravis (EAMG). With the downregulation of dendritic cells (DCs), TLR9 interruption reduced follicular helper T cells (Tfh) and germinal centre (GC) B cells, leading to decreased antibody production. In addition, TLR9+ B cells as well as total B cells in the spleen were inhibited by H154. These findings highlight the critical role of TLR9 in EAMG and suggest that the inhibition of the TLR9 pathway might be a potential pharmacological strategy for the treatment of myasthenia gravis.

Statins reduce the expressions of Tim-3 on NK cells and NKT cells in atherosclerosis.

3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitors (statins) have an immuno-regulatory effect in addition to lowing-lipids. Accumulated evidence showed that the expressions of T cell immunoglobulin- and mucin-domain-containing molecule-3 (Tim-3) on natural killer (NK) cells increased in atherosclerotic patients and animal models. In this study, 14 patients treated with rosuvastatin and 12 patients with atorvastatin for more than 3 months were included and 20 patients without statins treatment as control. Both statins treatment reduced the expressions of Tim-3 on NK cells and their subtypes, natural killer T (NKT) cells and CD3+ T cells, and increased the proportions of NKT cells among peripheral blood mononuclear cells, accompanied by the decreased levels of total cholesterol, low density lipoprotein, and increased ratios of high density lipoprotein to cholesterol. These may contribute to the functions of statins in the treatment of atherosclerosis.

ONX-0914, a selective inhibitor of immunoproteasome, ameliorates experimental autoimmune myasthenia gravis by modulating humoral response.

Accumulating evidence shows that the immunoproteasome participates in the immune response, beyond its initial role in the protein degradation. Here, we tested the effects of the selective immunoproteasome inhibitor, ONX-0914, on experimental autoimmune myasthenia gravis (EAMG). We found that ONX-0914 ameliorated the severity of ongoing EAMG by reducing the autoantibody affinity, accompanied with decreased Tfh cells and antigen presenting cells. Also it reduced the percentage of Th17 cells and inhibited the secretion of IL-17. Our data indicated ONX-0914 may bring benefit for MG therapy.

Caspase-1 inhibitor regulates humoral responses in experimental autoimmune myasthenia gravis via IL-6- dependent inhibiton of STAT3.

We have previously demonstrated that Cysteinyl aspartate-specific proteinase-1 (caspase-1) inhibitor ameliorates experimental autoimmune myasthenia gravis (EAMG) by inhibited cellular immune response, via suppressing DC IL-1 ß, CD4+ T and γdT cells IL-17 pathways. In this study, we investigated the effect of caspase-1 inhibitor on humoral immune response of EAMG and further explore the underlying mechanisms. An animal model of MG was induced by region 97-116 of the rat AChR α subunit (R97-116 peptide) in Lewis rats. Rats were treated with caspase-1 inhibitor Ac-YVAD-cmk intraperitoneally (i.p.) every second day from day 13 after the first immunization. Flow cytometry, western blot, immunofluorescence, and enzyme-linked immunosorbent assay (ELISA) were performed to evaluate the neuroprotective effect of caspase-1 inhibitor on humoral immune response of EAMG. The results showed that caspase-1 inhibitor reduced the relative affinity of anti-R97-116 IgG, suppressed germinal center response, decreased follicular helper T cells, and increased follicular regulatory T cells and regulatory B cells. In addition, we found that caspase-1 inhibitor inhibited humoral immunity response in EAMG rats via suppressing IL-6-STAT3-Bcl-6 pathways. These results suggest that caspase-1 inhibitor ameliorates EAMG by regulating humoral immune response, thus providing new insights into the development of myasthenia gravis and other autoimmune diseases therapies.

N-myc downstream-regulated gene 1 inhibits the proliferation and invasion of hepatocellular carcinoma cells via the regulation of integrin ß3.

N-myc downstream-regulated gene 1 (NDRG1) is a multifunctional protein associated with carcinogenesis and tumor progression. The function of NDRG1 in hepatocellular carcinoma (HCC) cells remains controversial. The present study investigated the role of NDRG1 in HCC as well as its molecular mechanism using a range of techniques, including western blot analysis, cellular proliferation test, wound healing assay and Transwell assay. In HCC, the levels of NDRG1 expression were highest in the cytoplasm, followed by the membrane, and were lowest in the nucleus. NDRG1 was revealed to inhibit the proliferation and invasion of BEL7402 cells, which facilitated the hypothesis that NDRG1 expression levels may be lower in cell line with a high metastatic potential compared with those in cell lines with a low metastatic potential. However, the present study identified that NDRG1 expression was higher in detached BEL7402 cells and MHCC-97H cells compared with that in attached BEL7402 cells and MHCC-97L cells. Thus, this finding was contrary to what was expected, suggesting that NDRG1 overexpression in the HCC with a high metastatic potential may be the compensatory mechanism. The human HCC BEL7402 cell line demonstrated a significant increase in the capability of motility, invasion and cellular proliferation following NDRG1-short hairpin RNA transfection. Integrin ß3 (ITGB3) protein expression was increased in NDRG1-downregulated BEL7402 cells and SMMC7721 cells compared with that in the control cells. The present study suggested that NDRG1 may be a potential anti-tumor target for the treatment of patients with HCC. A potential mechanism for these roles of NDRG1 is by regulating ITGB3 expression; however, this requires additional investigation.

Parthenolide inhibits the initiation of experimental autoimmune neuritis.

A growing body of evidence suggests the anti-inflammatory and antitumor effects of parthenolide (PAR). Here we show that PAR treatment inhibits the initiation of experimental autoimmune neuritis (EAN), suppresses the production of TNF-α, IFN-γ, IL-1ß and IL-17, and decreases Th1 and Th17 cells at early time point. However, such anti-inflammatory effect vanishes later and PAR impedes the recovery of EAN in late phase, which is accompanied with inhibited apoptosis of inflammatory cells. Our results indicate that PAR plays dual roles in EAN and it is not proper to be applied in autoimmune diseases of nervous system.

Astilbin ameliorates experimental autoimmune myasthenia gravis by decreased Th17 cytokines and up-regulated T regulatory cells.

Astilbin, a major bioactive compound extracted from Rhizoma smilacis glabrae (RSG), has been reported to possess immunosuppressive properties. Our study first evaluated the effect of astilbin on experimental autoimmune myasthenia gravis (EAMG) in Lewis rats. The results showed that astilbin could attenuate the severity of EAMG by decreasing antigen-specific autoantibodies with up-regulation of regulatory T cells and down-regulation of Th17 cells. In addition to, astilbin also reduced the efficiency of the antigen presenting cells on which the expression of MHC class II decreased. These results suggest that astilbin might be a candidate drug for immunoregulation of EAMG, and provide us new treatment ideas for human myasthenia gravis (MG).

ROCK inhibitor abolishes the antibody response in experimental autoimmune myasthenia gravis.

The Rho/Rho kinase (ROCK) pathway serves as molecular switches in many biological processes including the immune response. ROCK inhibitors lead to amelioration of some autoimmune diseases. The present study was designed to define whether a selective ROCK inhibitor, fasudil, was effective in experimental autoimmune myasthenia gravis (EAMG) and investigate the underlying mechanisms. Here we found fasudil effectively attenuated the development of ongoing EAMG. Fasudil abolished the antibody production and function by decreasing follicular helper T cells and CD19(+) B cells, especially germinal center B cells. Moreover, fasudil reduced the expression of CD80 on lymph node mononuclear cells. These findings suggest the inhibition of ROCK might be a potential therapeutic strategy for antibody-mediated autoimmune diseases.

Curcumin ameliorates experimental autoimmune myasthenia gravis by diverse immune cells.

Curcumin is a traditional Asian medicine with diverse immunomodulatory properties used therapeutically in the treatment of many autoimmune diseases. However, the effects of curcumin on myasthenia gravis (MG) remain undefined. Here we investigated the effects and potential mechanisms of curcumin in experimental autoimmune myasthenia gravis (EAMG). Our results demonstrated that curcumin ameliorated the clinical scores of EAMG, suppressed the expression of T cell co-stimulatory molecules (CD80 and CD86) and MHC class II, down-regulated the levels of pro-inflammatory cytokines (IL-17, IFN-γ and TNF-α) and up-regulated the levels of the anti-inflammatory cytokine IL-10, shifted the balance from Th1/Th17 toward Th2/Treg, and increased the numbers of NKR-P1(+) cells (natural killer cell receptor protein 1 positive cells, including NK and NKT cells). Moreover, the administration of curcumin promoted the differentiation of B cells into a subset of B10 cells, increased the anti-R97-166 peptide IgG1 levels and decreased the relative affinity indexes of anti-R97-116 peptide IgG. In summary, curcumin effectively ameliorate EAMG, indicating that curcumin may be a potential candidate therapeutic agent for MG.

Activation of the adenosine A2A receptor exacerbates experimental autoimmune neuritis in Lewis rats in association with enhanced humoral immunity.

Accumulated evidence demonstrated that Adenosine A2A receptor (A2AR) is involved in the inflammatory diseases. In the present study, we showed that a selective A2AR agonist, CGS21680, exacerbated experimental autoimmune neuritis in Lewis rats induced with bovine peripheral myelin. The exacerbation was accompanied with reduced CD4(+)Foxp3(+) T cells, increased CD4(+)CXCR5(+) T cells, B cells, dendritic cells and antigen-specific autoantibodies, which is possibly due to the inhibition of IL-2 induced by CGS21680. Combined with previous studies, our data indicate that the effects of A2AR stimulation in vivo are variable in different diseases. Caution should be taken in the use of A2AR agonists.

Synergistic Effect of Fluconazole and Calcium Channel Blockers against Resistant Candida albicans.

Candidiasis has increased significantly recently that threatens patients with low immunity. However, the number of antifungal drugs on the market is limited in comparison to the number of available antibacterial drugs. This fact, coupled with the increased frequency of fungal resistance, makes it necessary to develop new therapeutic strategies. Combination drug therapy is one of the most widely used and effective strategy to alleviate this problem. In this paper, we were aimed to evaluate the combined antifungal effects of four CCBs (calcium channel blockers), amlodipine (AML), nifedipine (NIF), benidipine (BEN) and flunarizine (FNZ) with fluconazole against C. albicans by checkerboard and time-killing method. In addition, we determined gene (CCH1, MID1, CNA1, CNB1, YVC1, CDR1, CDR2 and MDR1) expression by quantitative PCR and investigated the efflux pump activity of resistant candida albicans by rhodamine 6G assay to reveal the potential mechanisms. Finally, we concluded that there was a synergy when fluconazole combined with the four tested CCBs against resistant strains, with fractional inhibitory concentration index (FICI) <0.5, but no interaction against sensitive strains (FICI = 0.56 ~ 2). The mechanism studies revealed that fluconazole plus amlodipine caused down-regulating of CNA1, CNB1 (encoding calcineurin) and YVC1 (encoding calcium channel protein in vacuole membrane).

Exosomes derived from atorvastatin-modified bone marrow dendritic cells ameliorate experimental autoimmune myasthenia gravis by up-regulated levels of IDO/Treg and partly dependent on FasL/Fas pathway.

BACKGROUND: Previously, we have demonstrated that spleen-derived dendritic cells (DCs) modified with atorvastatin suppressed immune responses of experimental autoimmune myasthenia gravis (EAMG). However, the effects of exosomes derived from atorvastatin-modified bone marrow DCs (BMDCs) (statin-Dex) on EAMG are still unknown. METHODS: Immunophenotypical characterization of exosomes from atorvastatin- and dimethylsulfoxide (DMSO)-modified BMDCs was performed by electron microscopy, flow cytometry, and western blotting. In order to investigate whether statin-DCs-derived exosomes (Dex) could induce immune tolerance in EAMG, we administrated statin-Dex, control-Dex, or phosphate-buffered saline (PBS) into EAMG rats via tail vein injection. The tracking of injected Dex and the effect of statin-Dex injection on endogenous DCs were performed by immunofluorescence and flow cytometry, respectively. The number of Foxp3(+) cells in thymuses was examined using immunocytochemistry. Treg cells, cytokine secretion, lymphocyte proliferation, cell viability and apoptosis, and the levels of autoantibody were also carried out to evaluate the effect of statin-Dex on EAMG rats. To further investigate the involvement of FasL/Fas in statin-Dex-induced apoptosis, the underlying mechanisms were studied by FasL neutralization assays. RESULTS: Our data showed that the systemic injection of statin-Dex suppressed the clinical symptoms of EAMG rats. These statin-Dex had immune regulation functions in immune organs, such as the spleen, thymus, and popliteal and inguinal lymph nodes. Furthermore, statin-Dex exerted their immunomodulatory effects in vivo by decreasing the expression of CD80, CD86, and MHC class II on endogenous DCs. Importantly, the therapeutic effects of statin-Dex on EAMG rats were associated with up-regulated levels of indoleamine 2,3-dioxygenase (IDO)/Treg and partly dependent on FasL/Fas pathway, which finally resulted in decreased synthesis of anti-R97-116 IgG, IgG2a, and IgG2b antibodies. CONCLUSIONS: Our data suggest that atorvastatin-induced immature BMDCs are able to secrete tolerogenic Dex, which are involved in the suppression of immune responses in EAMG rats. Importantly, our study provides a novel cell-free approach for the treatment of autoimmune diseases.