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The transcription factor forkhead box protein O1 (FoxO1) is closely related to the occurrence and development of ovarian cancer (OC), however its role and molecular mechanisms remain unclear. Herein, we found that FoxO1 was highly expressed in clinical samples of OC patients and was significantly correlated with poor prognosis. FoxO1 knockdown inhibited the proliferation of OC cells in vitro and in vivo. ChIP‐seq combined with GEPIA2 and Kaplan–Meier database analysis showed that structural maintenance of chromosome 4 (SMC4) is a downstream target of FoxO1, and FoxO1 promotes SMC4 transcription by binding to its −1400/−1390 bp promoter. The high expression of SMC4 significantly blocked the tumor inhibition effect of FoxO1 knockdown. Furtherly, FoxO1 increased SMC4 mRNA abundance by transcriptionally activating methyltransferase‐like 14 (METTL14) and increasing SMC4 m6A methylation on its coding sequence region. The Cancer Genome Atlas dataset analysis confirmed a significant positive correlation between FoxO1, SMC4, and METTL14 expression in OC. In summary, this study revealed the molecular mechanisms of FoxO1 regulating SMC4 and established a clinical link between the expression of FoxO1/METTL14/SMC4 in the occurrence of OC, thus providing a potential diagnostic target and therapeutic strategy. [ABSTRACT FROM AUTHOR]

Acute aortic dissection (AAD) is one of the most common fatal diseases noted in vascular surgery. Human monocytes circulate in dynamic equilibrium and display a considerable heterogeneity. However, the role of monocytes in AAD remains elusive. In our recent study, we firstly obtained blood samples from 22 patients with Stanford type B AAD and 44 age-, sex-, and comorbidity-matched control subjects. And the monocyte proportions were evaluated by flow cytometry. Results showed that the percentage of total CD14+ monocytes in the blood samples of Stanford AAD patients was increased significantly compared with that of normal volunteers (P < 0.0005), and the absolute numbers of CD14brightCD16+ and CD14brightCD16- monocytes both increased significantly regardless of the percentage of PBMC or CD14+ cells, while CD14dimCD16+ monocytes displayed the opposite tendency. However, the percentage of CD14+ cells and its three subsets demonstrated no correlation with D-dimer (DD) and C-reactive protein (CRP). Then, blood mononuclear cell (PBMC) samples were collected by Ficoll density gradient centrifugation, followed with CD14+ magnetic bead sorting. After the purity of CD14+ cells was validated over 90%, AAD-related genes were concentrated in CD14+ monocytes. There were no significant differences observed with regard to the mRNA expression levels of MMP1 (P = 0.0946), MMP2 (P = 0.3941), MMP9 (P = 0.2919), IL-6 (P = 0.4223), and IL-10 (P = 0.3375) of the CD14+ monocytes in Stanford type B AAD patients compared with those of normal volunteers. The expression levels of IL-17 (P < 0.05) was higher in Stanford type B AAD patients, while the expression levels of TIMP1(P<0.05), TIMP2(P<0.01), TGF-β1 (P < 0.01), SMAD3 (P < 0.01), ACTA2 (P < 0.001), and ADAMTS-1 (P < 0.001) decreased. The data suggested that monocytes might play an important role in the development of Stanford type B AAD. Understanding of the production, differentiation, and function of monocyte subsets might dictate future therapeutic avenues for Stanford type B AAD treatment and can aid the identification of novel biomarkers or potential therapeutic targets for decreasing inflammation in AAD. [ABSTRACT FROM AUTHOR]

Caspase recruitment domain‐containing protein 9 (CARD9) is an adaptor protein and highly expressed in myeloid cells. Our previous study demonstrates a critical protective effect of CARD9 in the development of colitis‐associated colon cancer. Nevertheless, the effect of CARD9 in lung cancer remains unclear. Here, using a mouse Lewis lung cancer model, we found the tumor burden of CARD9−/− mice was much heavier than that in wild‐type (WT) mice. More myeloid‐derived suppressor cells (MDSCs) were accumulated and less cytotoxicity T lymphocyte was found in tumor tissues of CARD9−/− mice, compared to WT mice. Depleting MDSCs using anti‐Gr1 antibody can significantly decrease tumor burden in CARD9−/− mice. Furthermore, the noncanonical nuclear factor‐kappaB (NF‐κB) pathway was activated in CARD9−/− mice‐derived MDSCs. Deficiency of CARD9 enhanced expression of indoleamine 2,3‐dioxygenase (IDO) in MDSCs via noncanonical NF‐κB pathway. Moreover, correlations between CARD9 expressions and MDSCs relative genes (IDO, iNOS‐2 and arginase 1 [ARG‐1]) were further confirmed in tumor tissues from lung cancer patients. Taken together, we showed a CARD9‐NF‐κB‐IDO pathway in MDSCs which can inhibit the suppressive function of MDSCs and prevent lung cancer development. What's new? Myeloid‐derived suppressor cells (MDSCs) play a critical role in enabling tumor immune escape. Factors capable of counteracting MDSC activity in the tumor microenvironment remain largely unknown. Here, the authors identify caspase recruitment domain‐containing protein 9 (CARD9), a myeloid cell adaptor protein, as an inhibitor of MDSCs and indoleamine 2,3‐dioxygenase (IDO), an immunosuppressive enzyme produced by MDSCs. In mice, CARD deficiency was associated with increased lung tumor size and impaired immune response. Non‐canonical NF‐kB pathway signaling and IDO expression were enhanced in CARD‐deficient cells. The findings suggest that CARD9 is an important immune regulator in the lung tumor microenvironment. [ABSTRACT FROM AUTHOR]

Macrophages have variable functional phenotypes, high diversity, and plasticity and are involved in the pathogenesis of sepsis-induced liver injury. Alteration of macrophage polarization through activated (M1) macrophage to alternatively activated (M2) macrophage has emerged as a potential therapeutic strategy. This study was designed to explore the effect of a benzenediamine analog FC-99 on macrophage polarization in vitro and lipopolysaccharide- (LPS-) induced liver injury followed by the underlying mechanisms. For in vitro experiments, FC-99 inhibited M1-related macrophage factors and promoted M2-related markers induced by IL-4 in the mouse macrophage cell line RAW264.7. Moreover, FC-99-induced macrophages polarized to M2 phenotype which could be repressed by a PPAR-γ inhibitor but not STAT6 siRNA knockdown, indicating FC-99-induced M2 macrophage polarization through PPAR-γ rather than STAT6 signal. In LPS-induced septic mice, FC-99 pretreated mice displayed lower expression of M1 markers together with the increased M2 marker CD206 and improvement of liver injury. These findings illustrated that FC-99 could promote M2 macrophage polarization via PPAR-γ signaling and seemed to be a potential therapeutic candidate for inflammatory liver injury. [ABSTRACT FROM AUTHOR]

Accumulating evidence has shown that mammalian target of rapamycin (mTOR) pathway and myeloid‐derived suppressor cells (MDSCs) are involved in pathogenesis of inflammatory bowel diseases (IBDs). INK128 is a novel mTOR kinase inhibitor in clinical development. However, the exact roles of MDSCs and INK128 in IBD are unclear. Here, we showed that the INK128 treatment enhanced the resistance of mice to dextran sodium sulfate (DSS)–induced colitis and inhibited the differentiation of MDSCs into macrophages. Moreover, interferon (IFN)‐α level was elevated in INK128‐treated colitis mice. When stimulated with IFN‐α in vitro, MDSCs showed a superior immunosuppression activity. Of note, the regulatory T cells (Tregs) increased but Th1 cells decreased in INK128‐treated colitis mice. These results indicate that mTOR inhibitor INK128 attenuates DSS‐induced colitis via Treg expansion promoted by MDSCs. Our work provides a new evidence that INK128 is potential to be a therapeutic drug on DSS‐induced colitis via regulating MDSCs as well as maintaining Treg expansion. Mammalian target of rapamycin inhibitor INK128 attenuates dextran sodium sulfate–induced colitis by promotion of myeloid‐derived suppressor cells on regulatory T‐cell expansion. [ABSTRACT FROM AUTHOR]

Myeloid-derived suppressor cells ( MDSCs), including granulocytic (G)- MDSCs and monocytic (M)- MDSCs, play a critical role in tumor-induced T cell tolerance. MDSC immunosuppressive function and differentiation are significantly promoted in patients and B-cell lymphoma model mice. However, the mechanisms regulating these processes remain largely unclear. In the present study, we observed increased micro RNA (miR)-30a expression both in G- MDSCs and in M- MDSCs from B cell lymphoma model mice. After transfection with miR-30a mimics, the differentiation and suppressive capacities of MDSCs were significantly increased via up-regulation of arginase-1. Moreover, we showed that the 3′- UTR of suppressor of cytokine signaling 3 ( SOCS3) mRNA is a direct target of miR-30a. Decreased SOCS3 expression and activated Janus kinase-signal transducer and activator of transcription 3 signaling promote MDSC differentiation and suppressive activities. These findings provide new insights into the molecular mechanisms underlying MDSC expansion and function during B cell lymphoma development. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) possess the ability to modulate the immune response, and their abnormalities are related to several diseases. We previously reported that miR-30a expression significantly increased in the maternal–fetal interface during preeclampsia (PE), but the effects of miR-30a on the immunoregulatory characteristics of MSCs are unclear. In this study, we determined that miR-30a over-expression inhibited the IL-1β-elicited activation of the nuclear factor κB (NF-κB) and JNK signaling pathways and the production of IL-6, cyclooxygenase 2 (COX2) and IL-8 by targeting transforming growth factor-β-activated kinase 1 binding protein 3 (TAB3) in MSCs. Moreover, the over-expression of miR-30a also impaired MSCs’ anti-inflammatory effects on macrophages. These data demonstrated that miR-30a in MSCs may participate in the immune dysregulation of the maternal–fetal interface during PE. [ABSTRACT FROM AUTHOR]

Background and Purpose: Sepsis is a clinical condition characterized by overwhelming systemic inflammation with high mortality rate and high prevalence, but effective treatment is still lacking. Toll-like receptor 3 (TLR3) is an endogenous sensor, thought to regulate the amplification of immune response during sepsis. Modulators of TLR3 have an advantage in the treatment of sepsis. Here, we aimed to explore the mechanism of a monosubstituted 1,2-benzenediamine derivative FC-99 {N(1) -[(4-methoxy)methyl]-4-methyl-1,2-benzenediamine}on modulating TLR3 expression and its therapeutic potential on mouse model of sepsis.Experimental Approach: Cells were pretreated with FC-99 followed by poly(I:C) or IFN-α stimulation; TLR3 and other indicators were assayed. Female C57BL/6 mice were subjected to sham or caecal ligation puncture (CLP) surgery after i.p. injection of vehicle or FC-99; serum and tissues were collected for further experiments.Key Results: FC-99 suppressed inflammatory response induced by poly(I:C) with no effect on cell viability or uptake of poly(I:C). FC-99 also inhibited TLR3 expression induced by not only poly(I:C) but also by exogenous IFN-α. This inhibition of FC-99 was related to the poly(I:C)-evoked IRF3/IFN-α/JAK/STAT1 signalling pathway. In CLP-induced model of sepsis, FC-99 administration decreased mice mortality and serum levels of inflammatory factors, attenuated multiple organ dysfunction and enhanced bacterial clearance. Accordingly, systemic and local expression of TLR3 was reduced by FC-99 in vivo.Conclusion and Implications: FC-99 reversed TLR3 expression and ameliorate CLP-induced sepsis in mice. Thus, FC-99 will be a potential therapeutic candidate for sepsis. [ABSTRACT FROM AUTHOR]

In the present study, we investigated the effects of technetium-99 conjugated with methylene diphosphonate (99 Tc-MDP), an agent used in radionuclide therapy, on receptor activator of nuclear factor-κ B ligand (RANKL)-induced osteoclastogenesis and explored the underlying mechanisms., The murine macrophage cell line RAW264.7 and bone marrow-derived-macrophages from C57 BL/6 mice (BMM) were used as models for osteoclastogenesis in vitro. The expression of some key factors in RANKL (50 ng/mL)-induced osteoclastogenesis in RAW264.7 cells was investigated by flow cytometry and real-time reverse transcription-polymerase chain reaction (RT-PCR). To detect multinucleated osteoclast formation, RAW264.7 cells were induced with RANKL for 4 days, whereas BMM were induced by 50 ng/mL RANKL and 20 ng/mL macrophage colony-stimulating factor for 7 days, before being stained with tartrate-resistant acid phosphatase., Osteoclastogenesis was evaluated using the osteoclast markers CD51, matrix metalloproteinase (MMP)-9 and cathepsin K. At 0.01 μg/mL, 99 Tc- MDP significantly inhibited RANKL-induced osteoclastogenesis without any cytotoxicity. In addition, 99 Tc-MDP abolished the appearance of multinucleated osteoclasts., Real-time RT- PCR analysis of transcription factor expression revealed that 99 Tc-MDP inhibited the expression of c-Fos and nuclear factor of activated T cells. In addition, 99 Tc-MDP inhibited the expression of the inflammatory factors interleukin ( IL)-6, tumour necrosis factor-α and IL-1β. Finally, 99 Tc-MDP inhibited the activation of mitogen-activated protein kinases in RAW264.7 cells following RANKL stimulation., In conclusion, 99 Tc-MDP possesses anti-osteoclastogenic activity against RANKL-induced osteoclast formation. [ABSTRACT FROM AUTHOR]

Objective The human immune system exhibits sexual dimorphism in autoimmune diseases such as systemic lupus erythematosus (SLE). Female sex hormones, including 17β-estradiol, are strongly implicated in the gender bias in SLE. CD40 is a costimulatory molecule and plays a crucial role in modulating the immune response of effector cells. We have previously shown that 17β-estradiol up-regulated CD40 expression and altered minichromosome maintenance protein 6 (MCM6) gene expression in dendritic cells (DCs). The mechanism of the correlation between CD40 and MCM6 in the presence of 17β-estradiol remains unknown. This study was undertaken to elucidate this mechanism and to explain the role of MCM6 in the gender bias in SLE. Methods Bone marrow-derived DCs transfected with small interfering RNA (siRNA) for MCM6 were treated with 17β-estradiol in the absence or presence of CpG. The expression levels of costimulatory molecules, activity of MAPKs, and levels of MCM6 protein were measured. Moreover, the functions of DCs, including proliferation, apoptosis, endocytosis, and cytokine production, were analyzed. In addition, levels of messenger RNA for MCM6 were detected in DCs purified from SLE patients. Results Regardless of the presence or absence of CpG, 17β-estradiol induced CD40 expression via the activation of p38 and JNK, but not ERK. The activation of p38 and JNK enhanced MCM6 expression, which then induced CD40 expression. Suppression of MCM6 in DCs abolished the up-regulation of 17β-estradiol-induced CD40 expression. Importantly, MCM6 expression was significantly increased in SLE patients compared with healthy controls. Conclusion Our findings indicate that 17β-estradiol induces CD40 expression in DCs via p38 and JNK MAPKs in an MCM6-dependent manner. MCM6 may be a critical mediator of sex-based differences in autoimmune disease. [ABSTRACT FROM AUTHOR]

Objective Methods Results Conclusion Myeloid‐derived suppressor cells (MDSCs) contribute to the pathogenesis of systemic lupus erythematosus (SLE), in part due to promoting the survival of plasma cells. FoxO1 expression in monocytic MDSCs (M‐MDSCs) exhibits a negative correlation with the SLE Disease Activity Index score. This study aimed to investigate the hypothesis that M‐MDSC–specific FoxO1 deficiency enhances aberrant B cell function in aggressive SLE.We used GEO data sets and clinical cohorts to verify the clinical significance of FoxO1 expression and circulating M‐MDSCs. Using Cre‐LoxP technology, we generated myeloid FoxO1 deficiency mice (mFoxO1−/−) to establish murine lupus–prone models. The transcriptional stage was assessed by integrating chromatin immunoprecipitation (ChIP)–sequencing with transcriptomic analysis, luciferase reporter assay, and ChIP–quantitative polymerase chain reaction. Methylated RNA immunoprecipitation sequencing, RNA sequencing, and CRISPR‐dCas9 were used to identify N6‐adenosine methylation (m6A) modification. In vitro B cell coculture experiments, capmatinib intragastric administration, m6A‐modulated MDSCs adoptive transfer, and sample validation of patients with SLE were performed to determine the role of FoxO1 on M‐MDSCs dysregulation during B cell autoreacted with SLE.We present evidence that low FoxO1 is predominantly expressed in M‐MDSCs in both patients with SLE and lupus mice, and mice with myeloid FoxO1 deficiency (mFoxO1−/−) are more prone to B cell dysfunction. Mechanically, FoxO1 inhibits mesenchymal‐epithelial transition factor protein (Met) transcription by binding to the promoter region. M‐MDSCs FoxO1 deficiency blocks the Met/cyclooxygenase2/prostaglandin E2 secretion pathway, promoting B cell proliferation and hyperactivation. The Met antagonist capmatinib effectively mitigates lupus exacerbation. Furthermore, alkB homolog 5 (ALKBH5) targeting catalyzes m6A modification on FoxO1 messenger RNA in coding sequences and 3' untranslated regions. The up‐regulation of FoxO1 mediated by ALKBH5 overexpression in M‐MDSCs improves lupus progression. Finally, these correlations were confirmed in untreated patients with SLE.Our findings indicate that effective inhibition of B cells mediated by the ALKBH5/FoxO1/Met axis in M‐MDSCs could offer a novel therapeutic approach to manage SLE. [ABSTRACT FROM AUTHOR]

We have investigated the effects of technetium‐99 conjugated with methylene diphosphonate (99Tc‐MDP), an agent for radionuclide therapy, on receptor activator of nuclear factor‐κB ligand (RANKL)‐induced osteoclastogenesis, and explored its underlying mechanisms. A murine macrophage cell line RAW264.7 and bone marrow derived‐macrophages from C57BL/6 mice (BMMs) were used as models for osteoclastogenesis in vitro. The expression of some key factors in RANKL (50 ng/ml)‐induced osteoclastogenesis from RAW264.7 was investigated by flow cytometry and real‐time RT‐PCR. To detect multinucleated osteoclast formation, RAW264.7 was induced with RANKL for four days and BMMs were induced by RANKL (50 ng/ml) and macrophage colony‐stimulating factor (M‐CSF, 20 ng/ml) for seven days, and the cells were then stained with tartrate‐resistant acid phosphatase (TRAP). Osteoclast markers including CD51, matrix metalloproteinases 9 (MMP9) and Cathepsin K were used to evaluate osteoclastogenesis. 99Tc‐MDP (0.01 μg/ml) significantly inhibited RANKL‐induced osteoclastogenesis without any cytotoxicity. 99Tc‐MDP also dramatically abolished the appearance of multinucleated osteoclasts. Expressions of transcription factors, c‐Fos and nuclear factor of activated T‐cells (NFATc1), as well as inflammatory factors induced by RANKL were measured by real‐time RT‐PCR. 99Tc‐MDP inhibited the expressions of c‐Fos, NFATc1 and inflammatory factors such as interleukin 6 (IL‐6), tumor necrosis factor α (TNF‐α) and interleukin 1β (IL‐1β). Moreover, 99Tc‐MDP also inhibited the activation of mitogen‐activated protein kinases (MAPKs) in RAW264.7 cells under RANKL stimulation. In conclusion, 99Tc‐MDP possesses anti‐osteoclastogenic activity on RANKL‐induced osteoclast formation.© 2012 The Authors Clinical and Experimental Pharmacology and Physiology © 2012 Blackwell Publishing Asia Pty Ltd [ABSTRACT FROM AUTHOR]