Background The caspase-associated recruitment domain-containing protein (CARP) is expressed in almost all tissues. Recently, the tumor-suppressive function of CARP was discovered and attracted increasing attention. This study aimed to investigate the role of CARP in the carcinogenesis of human gastric carcinoma. Methodology/Principal Findings Compared with normal gastric tissue, the downregulation of CARP expression was observed in gastric carcinoma tissue by cDNA array and tissue microarray assay. In vitro, the gastric carcinoma cell line (BGC-823) was stably transfected with pcDNA3.1B-CARP or plus CARP siRNA, and we used MTT, flow cytometry, cell migration on type I collagen, cell-matrix adhesion assay and western blot analysis to investigate the potential anti-tumor effects of CARP. The data showed that overexpressing CARP suppressed the malignancy of gastric carcinoma BGC-823 cell line, including significant increases in apoptosis, as well as obvious decreases in cell proliferation, migration, adhesion ability, and tumor growth. The tumor-suppressive effects of CARP were almost restored by siRNA-directed CARP silence. In addition, overexpression of CARP induced G1 arrest, decreased the expressions of cyclin E and CDK2, and increased the expressions of p27, p53 and p21. In vivo, the tumor-suppressive effect of CARP was also verified. A single-nucleotide polymorphism (SNP) genotype of CARP (rs2297882) was located in the Kozak sequence of the CARP gene. The reporter gene assay showed that rs2297882 TT caused an obvious downregulation of activity of CARP gene promoter in BGC-823 cells. Furthermore, the association between rs2297882 and human gastric carcinoma susceptibility was analyzed in 352 cases and 889 controls. It displayed that the TT genotype of rs2297882 in the CARP gene was associated with an increased risk of gastric carcinoma. Conclusions/Significance CARP is a potential tumor suppressor of gastric carcinoma and the rs2297882 C>T phenotype of CARP may serve as a predictor of gastric carcinoma.
<p>(A) Representative IHC staining images showing the expressions of SLAMF7 and CCL2 in HCC samples. Scale bar: 200 μm (left) and 20 μm (right). (B) The prognostic prediction performances of SLAMF7 in combination with CCL2 for OS and DFS in our Fudan LCI HCC cohort.</p>
<p>(A) Immunoblot assays showing the phosphorylated or non-phosphorylated ERK1/2, p38, and JNK proteins in the indicated HCC cells. (B) Flow cytometry analyses of CD80 and CD206 expressions in THP-1-differentiated macrophages cocultured with the indicated HCC cells. (C) Chemotaxis assays showing the effect of supernatants from the indicated coculture systems on the migration abilities of THP-1-differentiated macrophages. Scale bar: 100 μm. (D) qPCR and ELISA analyses of CCL2 transcriptional and secretory levels in the indicated HCC cells. (E) Immunoblot assays of phosphorylated or non-phosphorylated ERK1/2, p38, and JNK proteins in the indicated HCC cells. (F) ChIP-qPCR analyses of ATF2 binding to the CCL2 gene promoter in HCC cell lines with SLAMF7 overexpression and knockdown. (G) Immunoblot assays of SLAMF7, and ATF2 protein levels in the indicated HCC cells. **P<0.01, and ***P<0.001, Student’s t test. Experiments were repeated three time and results were present as the mean ± SD.</p>
Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are severe inflammatory lung diseases. Methylprednisolone (MP) is a common drug against inflammation in clinic. In this study, we aim to investigate the protective effect of MP on ALI and potential mechanisms. Male BABL/c mice were injected through tail vein using lipopolysaccharide (LPS, 5 mg/kg) with or without 5 mg/kg MP. Lung mechanics, tissue injury and inflammation were examined. Macrophage subsets in the lung were identified by flow cytometry. Macrophages were cultured from bone marrow of mice with or without MP. Then, we analyzed and isolated the subsets of macrophages. These isolated macrophages were then co-cultured with CD4+ T cells, and the percentage of regulatory T cells (Tregs) was examined. The expression of IL-10 and TGF-β in the supernatant was measured. The Tregs immunosuppression function was examined by T cell proliferation assay. To disclose the mechanism of the induction of Tregs by M2c, we blocked IL-10 or/and TGF-β using neutralizing antibody. Respiratory physiologic function was significantly improved by MP treatment. Tissue injury and inflammation were ameliorated in the MP-treated group. After MP treatment, the number of M1 decreased and M2 increased in the lung. In in vitro experiment, MP promoted M2 polarization rather than M1. We then induced M1, M2a and M2c from bone marrow cells. M1 induced more Th17 while M2 induced more CD4+CD25+Fxop3+ Tregs. Compared with M2a, M2c induced more Tregs, and this effect could be blocked by anti-IL-10 and anti-TGF-β antibodies. However, M2a and M2c have no impact on Tregs immunosuppression function. In conclusion, MP ameliorated ALI by promoting M2 polarization. M2, especially M2c, induced Tregs without any influence on Tregs immunosuppression function.
Despite public awareness of its deleterious effects, smoking remains a major cause of death. Indeed, it is a risk factor for atherothrombotic complications and in line with this, the introduction of smoking ban in public areas reduced smoking-associated cardiovascular complications. Nonetheless, smoking remains a major concern, and molecular mechanisms by which it causes cardiovascular disease are not known. Peripheral blood monocytes from healthy smokers displayed increased JNK2 and tissue factor (TF) gene expression compared to non-smokers (n=15, p<0.05). Similarly, human aortic endothelial cells exposed to cigarette smoke total particulate matter (CS-TPM) revealed increased TF expression mediated by JNK2 (n=4; p<0.05). Wild-type and JNK2-/- mice were exposed to cigarette smoke for two weeks after which arterial thrombosis was investigated. Wild-type mice exposed to smoke displayed reduced time to thrombotic arterial occlusion (n=8; p<0.05) and increased tissue factor activity (n=7; p<0.05) as compared to wild-type controls (n=6), while JNK2-/-mice exposed to smoke maintained an unaltered thrombotic potential (n=8; p=NS) and tissue factor activity (n=8) comparable to that of JNK2-/- and wild-type controls (n=6; p=NS). Smoking caused an increased production of reactive oxygen species (ROS) in wild-type but not in JNK2-/- mice (n=7; p<0.05 for wild-type mice and n=5-6; p=NS for JNK2-/- mice). In conclusion, the MAP kinase JNK2 mediates cigarette smoke-induced TF activation, arterial thrombosis and ROS production. These results underscore a major role of JNK2 in smoke-mediated thrombus formation and may offer an attractive target to prevent smoke-related thrombosis in those subjects which do not manage quitting.
Human life expectancy has been significantly extended, which poses major challenges to our healthcare and social systems. Aging-associated cognitive impairment is attributed to endothelial dysfunction in the cardiovascular system and neurological dysfunction in the central nervous system. The central nervous system is considered an immune-privileged tissue due to the exquisite protection provided by the blood-brain barrier. The present review provides an overview of the structure and function of blood-brain barrier, extending the cell components of blood-brain barrier from endothelial cells and pericytes to astrocytes, perivascular macrophages and oligodendrocyte progenitor cells. In particular, the pathological changes in the blood-brain barrier in aging, with special focus on the underlying mechanisms and molecular changes, are presented. Furthermore, the potential preventive/therapeutic strategies against aging-associated blood-brain barrier disruption are discussed.
<div>Abstract<p>Immune checkpoint inhibitors have limited efficacy in hepatocellular carcinoma (HCC). Macrophages are the most abundant immune cells in HCC, suggesting that a better understanding of the intrinsic processes by which tumor cells regulate macrophages could help identify strategies to improve response to immunotherapy. As signaling lymphocytic activation molecule (SLAM) family members regulate various immune functions, we investigated the role of specific SLAM receptors in the immunobiology of HCC. Comparison of the transcriptomic landscapes of immunotherapy-responsive and nonresponsive patients with advanced HCC identified SLAMF7 upregulation in immunotherapy-responsive HCC, and patients with HCC who responded to immunotherapy also displayed higher serum levels of SLAMF7. Loss of Slamf7 in liver-specific knockout mice led to increased hepatocarcinogenesis and metastasis, elevated immunosuppressive macrophage infiltration, and upregulated PD-1 expression in CD8<sup>+</sup> T cells. HCC cell-intrinsic SLAMF7 suppressed MAPK/ATF2-mediated CCL2 expression to regulate macrophage migration and polarization <i>in vitro</i>. Mechanistically, SLAMF7 associated with SH2 domain-containing adaptor protein B (SHB) through its cytoplasmic 304 tyrosine site to facilitate the recruitment of SHIP1 to SLAMF7 and inhibit the ubiquitination of TRAF6, thereby attenuating MAPK pathway activation and <i>CCL2</i> transcription. Pharmacological antagonism of the CCL2/CCR2 axis potentiated the therapeutic effect of anti–PD-1 antibody in orthotopic HCC mouse models with low SLAMF7 expression. In conclusion, this study highlights SLAMF7 as a regulator of macrophage function and a potential predictive biomarker of immunotherapy response in HCC. Strategies targeting CCL2 signaling to induce macrophage repolarization in HCC with low SLAMF7 might enhance the efficacy of immunotherapy.</p>Significance:<p>CCL2 upregulation caused by SLAMF7 deficiency in hepatocellular carcinoma cells induces immunosuppressive macrophage polarization and confers resistance to immune checkpoint blockade, providing potential biomarkers and targets to improve immunotherapy response in patients.</p></div>
Abstract: Background: BK virus nephropathy (BKN) is recognized as a cause of graft loss in renal transplant patients. This may be related to the introduction of new and potent immunosuppressive regimens. In Japan, our experience regarding its prevalence, clinical significance, and outcome is still limited. In this study, our primary purpose is to outline the prevalence, outcome, and clinical characteristics of BKN as observed at Osaka University Hospital. Methods: We retrospectively analyzed 112 biopsy specimens from 87 renal transplant patients. All transplantations were from living donors. Of the 112 biopsy specimens, 71 were from protocol biopsies and 41 were from episode biopsies. Calcineurin inhibitors and corticosteroid were used in all patients (tacrolimus 32 and cyclosporin 55). In addition, azathioprine was used in 43 patients, mizoribine was used in 24 patients, and mycophenolate mofetil was used in 20 patients. BKN was diagnosed by light microscopic examination and a positive immunohistochemical staining of anti‐SV40 antibody in a biopsy specimen. In order to investigate the outcome and potential risk factors of patients with different histological staging, we divided the patients into groups A (mild histological change) and B (moderate or severe histological change). Results: Of the 87 patients, six were diagnosed with BKN. There were no significant differences between BKN patients and non‐BKN patients, except for the number of patients with graft loss (p < 0.001). Of the six BKN patients, three were in group A, and three were in group B. We recognized a significant difference between group A and group B in terms of anti‐rejection treatment including glucocorticoid, tacrolimus trough levels of over 8 ng/mL, episode of acute rejection within 1‐month post‐transplantation, and the time period between transplantation and BKN diagnosis. Conclusions: This is the first report of BKN in Japanese renal allograft recipients. In our hospital, the prevalence, risk factors, and outcome were similar to those previously for non‐Japanese recipients.