Proteomic analysis of DZIP3 interactome and its role in proliferation and metastasis in gastric cancer cells.

Gastric cancer is a serious malignant tumor in the world, accounting for the third cause of cancer death worldwide. The pathogenesis of gastric cancer is very complex, in which epigenetic inheritance plays an important role. In our study, we found that DZIP3 was significantly up-regulated in gastric cancer tissues as compared to adjacent normal tissue, which suggested it may be play a crucial part in gastric cancer. To clarify the mechanism of it, we further analyzed the interacting proteome and transcriptome of DZIP3. An association between DZIP3 and some epigenetic regulators, such as CUL4B complex, was verified. We also present the first proteomic characterization of the protein-protein interaction (PPI) network of DZIP3. Then, the transcriptome analysis of DZIP3 demonstrated that knockdown DZIP3 increased a cohort of genes, including SETD7 and ZBTB4, which have essential role in tumors. We also revealed that DZIP3 promotes proliferation and metastasis of gastric cancer cells. And the higher expression of DZIP3 is positively associated with the poor prognosis of several cancers. In summary, our study revealed a mechanistic role of DZIP3 in promoting proliferation and metastasis in gastric cancer, supporting the pursuit of DZIP3 as a potential target for gastric cancer therapy.

Efficacy and Safety of Tofacitinib in Patients with Polymyalgia Rheumatica (EAST PMR): An open-label randomized controlled trial.

BACKGROUND: Polymyalgia rheumatica (PMR) is a common inflammatory disease in elderly persons whose mechanism of pathogenesis has not been elucidated. Glucocorticoids are the main first-line treatments but result in numerous side effects. Therefore, there is a need to explore pathogenetic factors and identify possible glucocorticoid-sparing agents. We aimed to study the pathogenetic features of the disease and assess the efficacy and safety of Janus tyrosine kinase (JAK)-inhibitor tofacitinib in patients with PMR. METHODS AND FINDINGS: We recruited treatment-naïve PMR patients from the First Affiliated Hospital, Zhejiang University School of Medicine, between September 2020 and September 2022. In the first cohort, we found that the gene expression patterns of peripheral blood mononuclear cells (PBMCs) in 11 patients (10 female, 1 male, age 68.0 ± 8.3) with newly diagnosed PMR were significantly different from 20 healthy controls (17 female, 3 male, age 63.7 ± 9.8) by RNA sequencing. Inflammatory response and cytokine-cytokine receptor interaction were the most notable pathways affected. We observed marked increases in expression of IL6R, IL1B, IL1R1, JAK2, TLR2, TLR4, TLR8, CCR1, CR1, S100A8, S100A12, and IL17RA, which could trigger JAK signaling. Furthermore, tofacitinib suppressed the IL-6R and JAK2 expression of CD4+T cells from patients with PMR in vitro. In the second cohort, patients with PMR were randomized and treated with tofacitinib or glucocorticoids (1/1) for 24 weeks. All PMR patients underwent clinical and laboratory examinations at 0, 4, 8, 12, 16, 20, and 24 weeks, and PMR activity disease scores (PMR-AS) were calculated. The primary endpoint was the proportion of patients with PMR-AS ≤10 at weeks 12 and 24. Secondary endpoints: PMR-AS score, c-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) at weeks 12 and 24. Thirty-nine patients with newly diagnosed PMR received tofacitinib, and 37 patients received glucocorticoid. Thirty-five patients (29 female, 6 male, age 64.4 ± 8.4) and 32 patients (23 female, 9 male, age 65.3 ± 8.7) patients completed the 24-week intervention, respectively. There were no statistically significant differences in primary or secondary outcomes. At weeks 12 and 24, all patients in both groups had PMR-AS <10. PMR-AS, CRP, and ESR were all significantly decreased in both groups. No severe adverse events were observed in either group. Study limitations included the single-center study design with a short observation period. CONCLUSIONS: We found that JAK signaling was involved in the pathogenesis of PMR. Tofacitinib effectively treated patients with PMR as glucocorticoid does in this randomized, monocenter, open-label, controlled trial (ChiCTR2000038253). TRIAL REGISTRATION: This investigator-initiated clinical trial (IIT) had been registered on the website (http://www.chictr.org.cn/, ChiCTR2000038253).

TACE responser NDRG1 acts as a guardian against ferroptosis to drive tumorgenesis and metastasis in HCC.

BACKGROUND: The treatment efficacy of transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) varies widely between individuals. The aim of this study was to identify subtype landscapes and responser related to TACE, and further clarify the regulatory effect and corresponding mechanism of NDRG1 on HCC tumorgenesis and metastasis. METHODS: The principal component analysis (PCA) algorithm was used to construct a TACE response scoring (TRscore) system. The random forest algorithm was applied to identify the TACE response-related core gene NDRG1 of HCC, and its role in the prognosis of HCC was explored. The role of NDRG1 in the progression and metastasis of HCC and functional mechanism were confirmed using several experimental methods. RESULTS: Based on the GSE14520 and GSE104580 cohorts, we identified 2 TACE response-related molecular subtypes for HCC with significant differences in clinical features, and the TACE prognosis of Cluster A was significantly better than that of Cluster B (p < 0.0001). We then established the TRscore system and found that the low TRscore group showed a higher probability of survival and a lower rate of recurrence than the high TRscore group (p < 0.05) in both the HCC and TACE-treated HCC cohorts within the GSE14520 cohort. NDRG1 was determined to be the the hub gene associated with the TACE response of HCC and its high expression suggested a poor prognosis. Furthermore, The suppression of NDRG1 konckdown in tumorgenesis and metastasis of HCC was clarified in both vivo and vitro, which was importantly achieved through inducing ferroptosis in HCC cells, especially contributing to RLS3-induced ferroptosis. CONCLUSION: The constructed TACE response-related molecular subtypes and TRscores can specifically and accurately predict TACE prognosis for HCC. In addition, the TACE response-related hub gene NDRG1 may act as a guardian against ferroptosis to drive tumorgenesis and metastasis in HCC, which laid a new foundation for the development of new potential targeted therapy strategies to improve disease prognosis in HCC patients.

SMYD3 associates with the NuRD (MTA1/2) complex to regulate transcription and promote proliferation and invasiveness in hepatocellular carcinoma cells.

BACKGROUND: SMYD3, a member of the SET and MYND domain-containing (SMYD) family, is a histone methyltransferase (HMT) and transcription factor that plays an important role in transcriptional regulation in human carcinogenesis. RESULTS: Using affinity purification and mass spectrometry assays to identify SMYD3-associated proteins in hepatocellular carcinoma (HCC) cells, we found several previously undiscovered SMYD3-interacting proteins, including the NuRD (MTA1/2) complex, the METTL family, and the CRL4B complex. Transcriptomic analysis of the consequences of knocking down SMYD3, MTA1, or MTA2 in HCC cells showed that SMYD3/NuRD complex targets a cohort of genes, some of which are critically involved in cell growth and migration. qChIP analyses showed that SMYD3 knockdown led to a significant reduction in the binding of MTA1 or MTA2 to the promoters of IGFBP4 and led to a significant decrease in H4K20me3 and a marked increase in H4Ac at the IGFBP4 promoter. In addition, we demonstrated that SMYD3 promotes cell proliferation, invasion, and tumorigenesis in vivo and in vitro and found that its expression is markedly upregulated in human liver cancer. Knockdown of MTA1 or MTA2 had the same effect as knockdown of SMYD3 on proliferation and invasion of hepatocellular carcinoma cells. Catalytic mutant SMYD3 could not rescue the phenotypic effects caused by knockdown of SMYD3. Inhibitors of SMYD3 effectively inhibited the proliferation and invasiveness of HCC cells. CONCLUSIONS: These findings revealed that SMYD3 could transcriptionally repress a cohort of target genes expression by associating with the NuRD (MTA1/2) complex, thereby promoting the proliferation and invasiveness of HCC cells. Our results support the case for pursuing SMYD3 as a practical prognostic marker or therapeutic target against HCC.

Piperlongumine synergistically enhances the antitumour activity of sorafenib by mediating ROS-AMPK activation and targeting CPSF7 in liver cancer.

Sorafenib, a multikinase inhibitor, is the first-line agent for advanced liver cancer. Sorafenib strongly inhibits both cell proliferation and tumour angiogenesis. However, the development of drug resistance hampers its anticancer efficacy. To improve the antitumour activity of sorafenib, we demonstrate that piperlongumine (PL), an alkaloid isolated from the fruits and roots of Piper longum L., enhances the cytotoxicity of sorafenib in HCCLM3 and SMMC7721 cells using the cell counting kit-8 test. Flow cytometry analysis indicated that PL and sorafenib cotreatment induced robust reactive oxygen species (ROS) generation and mitochondrial dysfunction, thereby increasing the number of apoptotic cells and the ratio of G2/M phase cells in both HCCLM3 and SMMC7721 cells. Furthermore, AMP-protein kinase (AMPK) signalling was activated by excess ROS accumulation and mediated growth inhibition in response to PL and sorafenib cotreatment. RNA-sequencing analysis indicated that PL treatment disrupted RNA processing in HCCLM3 cells. In particular, PL treatment decreased the expression of cleavage and polyadenylation specificity factor 7 (CPSF7), a subunit of cleavage factor I, in a time- and concentration-dependent manner in HCCLM3 and SMMC7721 cells. CPSF7 knockdown using a gene interference strategy promoted growth inhibition of PL or sorafenib monotherapy, whereas CPSF7 overexpression alleviated the cytotoxicity of sorafenib in cultured liver cancer cells. Finally, PL and sorafenib coadministration significantly reduced the weight and volume of HCCLM3 cell xenografts in vivo. Taken together, our data indicate that PL displays potential synergistic antitumour activity in combination with sorafenib in liver cancer.

Post-translational modifications in T cells in systemic erythematosus lupus.

Systemic erythematosus lupus (SLE) is a classic autoimmune disease characterized by multiple autoantibodies and immune-mediated tissue damage. The aetiology of this disease is still unclear. A new drug, belimumab, which acts against the B-lymphocyte stimulator (BLyS), can effectively improve the condition of SLE patients, but it cannot resolve all SLE symptoms. The discovery of novel, precise therapeutic targets is urgently needed. It is well known that abnormal T-cell function is one of the most crucial factors contributing to the pathogenesis of SLE. Protein post-translational modifications (PTMs), including phosphorylation, glycosylation, acetylation, methylation, ubiquitination and SUMOylation have been emphasized for their roles in activating protein activity, maintaining structural stability, regulating protein-protein interactions and mediating signalling pathways, in addition to other biological functions. Summarizing the latest data in this area, this review focuses on the potential roles of diverse PTMs in regulating T-cell function and signalling pathways in SLE pathogenesis, with the goal of identifying new targets for SLE therapy.

Microfluid-based soft metasurface for tunable optical activity in THz wave.

Metasurfaces are usually planar structures and do not possess intrinsic chirality and therefore hardly generate optical activity. Here we realized a tunable optical activity in a terahertz wave through a microfluid-based soft metasurface. The meta-atom is a chiral structured microchannel made of soft polydimethylsiloxane and injected with the liquid metal Galinstan. A microfluid pressure system is bonded to the metasurface to reconfigure all meta-atoms simultaneously. By pumping glycerol liquid into the pressure system, the metasurface is deformed from a planar structure to a three dimensional one, which manifests intrinsic chirality for optical activity realization. By controlling the injected glycerol volume, a polarization rotation from 0°to 14° at 0.19 THz is demonstrated. The soft metasurface with tunable optical activity can be flexibly applied in various applications such as polarization microscopy, bio-detection and material analysis, etc.

USP9X promotes apoptosis in cholangiocarcinoma by modulation expression of KIF1Bß via deubiquitinating EGLN3.

BACKGROUND: Cholangiocarcinoma represents the second most common primary liver malignancy. The incidence rate has constantly increased over the last decades. Cholangiocarcinoma silent nature limits early diagnosis and prevents efficient treatment. METHODS: Immunoblotting and immunohistochemistry were used to assess the expression profiling of USP9X and EGLN3 in cholangiocarcinoma patients. ShRNA was used to silence gene expression. Cell apoptosis, cell cycle, CCK8, clone formation, shRNA interference and xenograft mouse model were used to explore biological function of USP9X and EGLN3. The underlying molecular mechanism of USP9X in cholangiocarcinoma was determined by immunoblotting, co-immunoprecipitation and quantitative real time PCR (qPCR). RESULTS: Here we demonstrated that USP9X is downregulated in cholangiocarcinoma which contributes to tumorigenesis. The expression of USP9X in cholangiocarcinoma inhibited cell proliferation and colony formation in vitro as well as xenograft tumorigenicity in vivo. Clinical data demonstrated that expression levels of USP9X were positively correlated with favorable clinical outcomes. Mechanistic investigations further indicated that USP9X was involved in the deubiquitination of EGLN3, a member of 2-oxoglutarate and iron-dependent dioxygenases. USP9X elicited tumor suppressor role by preventing degradation of EGLN3. Importantly, knockdown of EGLN3 impaired USP9X-mediated suppression of proliferation. USP9X positively regulated the expression level of apoptosis pathway genes de through EGLN3 thus involved in apoptosis of cholangiocarcinoma. CONCLUSION: These findings help to understand that USP9X alleviates the malignant potential of cholangiocarcinoma through upregulation of EGLN3. Consequently, we provide novel insight into that USP9X is a potential biomarker or serves as a therapeutic or diagnostic target for cholangiocarcinoma.

Risk of macrophage activation syndrome in patients with adult-onset Still's disease with skin involvement: A retrospective cohort study.

BACKGROUND: Small case series and case reports indicated that atypical persistent pruritic eruptions (PPEs), another type of skin lesions seen in adult-onset Still's disease (AOSD), imply a worse prognosis than typical evanescent rashes. OBJECTIVE: To investigate clinical characteristics and macrophage activation syndrome (MAS) occurrence in AOSD with PPEs. METHODS: A retrospective cohort study analyzed 150 patients with AOSD with rashes at the First Affiliated Hospital of Zhejiang University from January 2013 to December 2019. RESULTS: Patients with AOSD with PPEs had higher lactate dehydrogenase (492.00 U/L vs 382.00 U/L; P < .001) and ferritin (6944.10 ng/ml vs 4286.60 ng/ml; P = .033), and lower fibrinogen (5.05 g/L vs 5.77 g/L; P = .014) than those with evanescent rashes. Patients with AOSD with PPEs had a higher incidence (17.4% vs 3.1%, P = .006) and cumulative event rate for MAS (P = .008) and tended to receive high-dose glucocorticoid (36% vs 20.3%; P = .036). Multivariate analysis indicated that PPEs (hazard ratio [HR], 5.519; 95% confidence interval [CI], 1.138-26.767; P = .034), aspartate aminotransferase of greater than 120 U/L (HR, 8.084; 95% CI, 1.728-37.826; P = .008), and splenomegaly (HR, 21.152; 95% CI, 2.263-197.711; P = .007) were independent risk factors for MAS. LIMITATIONS: Single-center, retrospective nature, small sample size. CONCLUSION: PPEs indicated increased severity and MAS occurrence versus evanescent rashes. PPEs, aspartate aminotransferase of greater than 120 U/L, and splenomegaly were risk factors for MAS in AOSD with skin involvement.

Aminooxyacetic acid attenuates post-infarct cardiac dysfunction by balancing macrophage polarization through modulating macrophage metabolism in mice.

Excessive activation of pro-inflammatory M1 macrophages following acute myocardial infarction (MI) aggravates adverse cardiac remodelling and heart dysfunction. There are two break points in the tricarboxylic acid cycle of M1 macrophages, and aspartate-arginosuccinate shunt compensates them. Aminooxyacetic acid (AOAA) is an inhibitor of aspartate aminotransferase in the aspartate-arginosuccinate shunt. Previous studies showed that manipulating macrophage metabolism may control macrophage polarization and inflammatory response. In this study, we aimed to clarify the effects of AOAA on macrophage metabolism and polarization and heart function after MI. In vitro, AOAA inhibited lactic acid and glycolysis and enhanced ATP levels in classically activated M1 macrophages. Besides, AOAA restrained pro-inflammatory M1 macrophages and promoted anti-inflammatory M2 phenotype. In vivo, MI mice were treated with AOAA or saline for three consecutive days. Remarkably, AOAA administration effectively inhibited the proportion of M1 macrophages and boosted M2-like phenotype, which subsequently attenuated infarct size as well as improved post-MI cardiac function. Additionally, AOAA attenuated NLRP3-Caspase1/IL-1ß activation and decreased the release of IL-6 and TNF-α pro-inflammatory cytokines and reciprocally increased IL-10 anti-inflammatory cytokine level in both ischaemic myocardium and M1 macrophages. In conclusion, short-term AOAA treatment significantly improves cardiac function in mice with MI by balancing macrophage polarization through modulating macrophage metabolism and inhibiting NLRP3-Caspase1/IL-1ß pathway.

Polyvinyl alcohol: a high-resolution hydrogel resist for humidity-sensitive micro-/nanostructure.

A high-resolution nanopatterning technique is desirable with the present rapid development of hydrogel nanodevices. Here, we demonstrate that polyvinyl alcohol (PVA), a popular polymeric hydrogel, can function as the negative-tone resist for electron beam lithography (EBL) with a resolution capability as narrow as 50 nm half-pitch. Furthermore, the hydrophilic groups of PVA are stable after EBL exposure, and thus the pattern still shows rapid responsivity to humidity change. An aqueous nanopatterning process including dissolution, spin-coating and development is setup, which is friendly for organic device fabrication free of organic solvent. This high-resolution nanopatterning technique with PVA is helpful for the design and realization of hydrogel-related nanodevices in the future.

PD-1+CXCR5-CD4+T cells are correlated with the severity of systemic lupus erythematosus.

OBJECTIVES: PD-1+CXCR5-CD4+T peripheral helper (Tph) cells, a recently identified T cell subset, are proven to promote B cell responses and antibody production in rheumatoid arthritis, but their role in the pathogenesis of SLE is unknown. We explored the role of Tph in lupus disease development. METHODS: This cohort study included 68 patients with SLE and 41 age- and sex-matched healthy individuals. The frequency of PD-1+CXCR5-CD4+T cells was analysed in peripheral blood by flow cytometry. Inducible T-cell costimulator, CD38, MHC-II, IL-21, CXCR3 and CCR6 expression were measured in Tph cells. Comparisons between the two groups were performed, and correlations between Tph cells and other parameters were investigated. RESULTS: We revealed a markedly expanded population of Tph cells (8.31 ± 5.45 vs 2.86 ± 1.31%, P < 0.0001) in the circulation of patients with SLE (n = 68), compared with healthy controls (n = 41). Tph cells were much higher in the active group than in the inactive group (14.21 ± 5.21 vs 5.49 ± 2.52%, P < 0.0001). Tph cells were significantly associated with SLEDAI score (r = 0.802), ESR (r = 0.415), IgG (r = 0.434), C3 (r = -0.543), C4 (r = -0.518) and IL-21 level (r = 0.628), and ANA titre (r = 0.272). Furthermore, Tph cells were much higher in lupus patients with arthritis, nephritis, rash, alopecia, pleuritis, pericarditis and haematological involvement. Tph cells were associated with CD138+/CD19+ plasma cells (r = 0.518). Furthermore, MHC-II, inducible T-cell costimulator, CD38, and IL-21 expression were all higher in Tph cells from SLE patients compared with healthy controls. CXCR3+CCR6-Tph (Tph1) cells were expanded in the SLE patients. CONCLUSION: Our data show that relative number of Tph cells is correlated with disease measures in patients with SLE, suggesting an important role in lupus disease development.

Well-being and health-related quality of life in new-generation migrant workers in Zhejiang province, China.

BACKGROUND: The purpose of this study is to evaluate the reliability and validity of the multiple happiness questionnaire (MHQ) in new-generation migrant workers (NGMW), to compare the difference of well-being and Health-Related Quality of Life (HRQOL) in NGMW with first-generation migrant workers (FGMW) and urban workers (UW), and to explore the relationship between well-being and HRQOL and analyze influential factors to well-being in NGMW in Zhejiang province, China. METHODS: By stratified sampling, 542 NGMW, 226 FGMW and 200 UW had completed the questionnaires in 2018. Cronbach's alpha coefficient (a) for internal consistency of the multiple happiness questionnaire (MHQ) was used. Factor analysis was applied for construct validity. Scores of well-being and HRQOL were compared between NGMW and control groups. Spearman's correlation was performed to clarify the relationship between well-being and HRQOL in NGMW. Multiple linear regression analytical methods were used to adjust confounding effects and to identify the variables that were associated with well-being. RESULTS: MHQ had good internal consistency (Cronbach's alpha overall was 0.960, subscales ranged from 0.754 to 0.957) and structural validity based on factor analysis. Except for life satisfaction and altruism commitment, there was a positive correlation between well-being and HRQOL in NGMW. There were significant differences in psychological well-being (PWB), health concern, subjective vitality, physical component summary (PCS) and mental component summary (MCS) between NGMW and FGMW. Compared to UW, NGMW's general well-being (GWB), subjective well-being (SWB), life satisfaction, positive relation and altruism commitment scores were lower and their negative affect was higher. The GWB score was related to MCS, PCS, self-reported social status, marital status, age and monthly income. CONCLUSION: The results suggest that the MHQ is a reliable and valid measure for well-being in NGMW. There is a significant difference in well-being and HRQOL between NGMW and control groups. Well-being is higher in NGMW than in FGMW, but is lower than in UW. Well-being is related with HRQOL and may be affected by MCS, PCS, self-reported social status, marital status, age and monthly income in NGMW.

Hypercapnia downregulates hypoxia-induced lysyl oxidase expression in pulmonary artery smooth muscle cells via inhibiting transforming growth factor ß1 signalling.

Hypoxic pulmonary arterial hypertension is characterized by elevated pulmonary vascular resistance and remodelling. Transforming growth factor-ß1 (TGF-ß1 ) is the master regulator in cellular response to hypoxia which can directly target lysyl oxidase (LOX). This study aimed to determine whether hypercapnia attenuates hypoxic pulmonary hypertension via regulating TGF-ß1 and LOX signalling. We found that exposure to hypercapnia ameliorated the increase in mean pulmonary artery pressure (mPAP) and ratio of right ventricle to left ventricle plus septum (RV/(LV + S)) induced by hypoxia but had no effect on mPAP and RV/(LV + S) in normoxia-exposed control. In addition, exposure to hypoxia upregulated the mRNA and protein levels of LOX and TGF-ß1 in rat PASMCs both in vivo and in vitro, but these effects were abrogated by concurrent exposure to hypercapnia. The downregulation of LOX in rat PASMCs induced by hypercapnia was reversed by the administration with TGF-ß1 , while TGF-ß1 knockdown repressed the upregulation of LOX in hypoxia-exposed rat PASMCs. In conclusion, hypoxia upregulates LOX and TGF-ß1 expression in PASMCs and contributes to pulmonary hypertension. Hypercapnia downregulates hypoxia-induced LOX expression and alleviates hypoxia-associated pulmonary hypertension via inhibiting TGF-ß1 signalling. SIGNIFICANCE OF THE STUDY: Hypoxia-induced upregulation of TGF-ß1 , PDGF, and HIF-1α plays a pivotal role in PAH, but molecular mechanism of how hypoxia regulates LOX expression is not clear. In the present study, we showed that mRNA and protein expression levels of LOX were substantially increased when TGF-ß1 was induced by hypoxia, and the effects were reversed by TGF-ß1 knockdown. Our study indicates that TGF-ß1 is implicated in the regulation of LOX.

Nicotine induces endothelial dysfunction and promotes atherosclerosis via GTPCH1.

Smoking is a major preventable risk factor for atherosclerosis. However, the causative link between cigarette smoke and atherosclerosis remains to be established. The objective of this study is to characterize the role of GTP cyclohydrolase 1 (GTPCH1), the rate-limiting enzyme for de novo tetrahydrobiopterin (BH4) synthesis, in the smoking-accelerated atherosclerosis and the mechanism involved. In vitro, human umbilical vein endothelial cells were treated with nicotine, a major component of cigarette smoke, which reduced the mRNA and protein levels of GTPCH1 and led to endothelial dysfunction. GTPCH1 overexpression or sepiapterin could attenuate nicotine-reduced nitric oxide and -increased reactive oxygen species levels. Mechanistically, human antigen R (HuR) bound with the adenylateuridylate-rich elements of the GTPCH1 3' untranslated region and increased its stability; nicotine inhibited HuR translocation from the nucleus to cytosol, which downregulated GTPCH1. In vivo, nicotine induced endothelial dysfunction and promoted atherosclerosis in ApoE-/- mice, which were attenuated by GTPCH1 overexpression or BH4 supplement. Our findings may provide a novel and promising approach to atherosclerosis treatment.

TGF-ß-Induced Regulatory T Cells Directly Suppress B Cell Responses through a Noncytotoxic Mechanism.

Foxp3(+) regulatory T cells (Treg) playing a crucial role in the maintenance of immune tolerance and prevention of autoimmune diseases consist of thymus-derived naturally occurring CD4(+)Foxp3(+) Treg cells (nTreg) and those that can be induced ex vivo with TGF-ß (iTreg). Although both Treg subsets share similar phenotypes and functional characteristics, they also have potential biologic differences on their biology. The role of iTreg in regulating B cells remains unclear so far. The suppression assays of Treg subsets on activation, proliferation, and Abs production of B cells were measured using a Treg and B cell coculture system in vitro. Transwell and Ab blockade experiments were performed to assess the roles of cell contact and soluble cytokines. Treg were adoptively transferred to lupus mice to assess in vivo effects on B cells. Like nTreg, iTreg subset also directly suppressed activation and proliferation of B cells. nTreg subset suppressed B cell responses through cytotoxic manner related to expression of granzyme A, granzyme B, and perforin, whereas the role of iTreg subset on B cells did not involve in cytotoxic action but depending on TGF-ß signaling. Furthermore, iTreg subset can significantly suppress Ab produced by lupus B cells in vitro. Comparison experiments using autoantibodies microarrays demonstrated that adoptive transfer of iTreg had a superior effect than nTreg subset on suppressing lupus B cell responses in vivo. Our data implicate a role and advantage of iTreg subset in treating B cell-mediated autoimmune diseases, boosting the translational potential of these findings.

Interactions between interleukin-6 and myeloid-derived suppressor cells drive the chemoresistant phenotype of hepatocellular cancer.

Emerging evidence implicates an important role for myeloid-derived suppressor cells (MDSCs) in tumor growth, angiogenesis and metastasis. However, limited knowledge is known about the function of MDSCs in response to chemotherapies. In this study, we find that drug-resistant hepatocellular cancer (HCC) cells-derived conditioned medium significantly enhances the expansion and immunosuppressive function of MDSCs compared to their parental sensitive cells, which is demonstrated by increased level of arginase, nitric oxide (NO), and reactive oxygen species (ROS). Next, we reveal that drug-resistant HCC cells-derived IL-6 activated MDSCs, which is demonstrated by using an anti-IL-6 neutralizing antibody that caused a reduced MDSC immunosuppressive activity. More importantly, the depletion of MDSC via the administration of anti-Gr-1 antibody or the blockade of IL-6 signaling sensitized 5-FU-resistant H22 hepatoma to chemotherapy in the immunocompetent C57BL/6N mice. In primary human HCC, IL-6 expression levels strongly correlate with an MDSC phenotype and chemotherapy response in HCC patients. In conclusion, these results describe a role of IL-6 in the drug resistance in HCC chemotherapy and suggest that MDSC-targeting treatments may be potential therapeutic strategy for HCC chemoresistance.

In vitro induction of T regulatory cells by a methylated CpG DNA sequence in humans: Potential therapeutic applications in allergic and autoimmune diseases.

BACKGROUND: Allergic and autoimmune diseases comprise a group of inflammatory disorders caused by aberrant immune responses in which CD25+ Forkhead box P3-positive (FOXP3+) T regulatory (Treg) cells that normally suppress inflammatory events are often poorly functioning. This has stimulated an intensive investigative effort to find ways of increasing Tregs as a method of therapy for these conditions. One such line of investigation includes the study of how ligation of Toll-like receptors (TLRs) by CpG oligonucleotides (ODN) results in an immunostimulatory cascade that leads to induction of T-helper (Th) type 1 and Treg-type immune responses. OBJECTIVE: The present study investigated the mechanisms by which calf thymus mammalian double-stranded DNA (CT-DNA) and a synthetic methylated DNA CpG ODN sequence suppress in vitro lymphoproliferative responses to antigens, mitogens, and alloantigens when measured by [3H]-thymidine incorporation and promote FoxP3 expression in human CD4+ T cells in the presence of transforming growth factor (TGF) beta and interleukin-2 (IL-2). METHODS: Lymphoproliferative responses of peripheral blood mononuclear cells from four healthy subjects or nine subjects with systemic lupus erythematosus to CT-DNA or phytohemagglutinin (PHA) was measured by tritiated thymidine ([3H]-TdR) incorporation expressed as a stimulation index. Mechanisms of immunosuppressive effects of CT-DNA were evaluated by measurement of the degree of inhibition to lymphoproliferative responses to streptokinase-streptodornase, phytohemagglutinin (PHA), concanavalin A (Con A), pokeweed mitogen (PWM), or alloantigens by a Con A suppressor assay. The effects of CpG methylation on induction of FoxP3 expression in human T cells were measured by comparing inhibitory responses of synthetic methylated and nonmethylated 8-mer CpG ODN sequences by using cell sorting, in vitro stimulation, and suppressor assay. RESULTS: Here, we showed that CT-DNA and a synthetic methylated DNA 8-mer sequence could suppress antigen-, mitogen-, and alloantigen-induced lymphoproliferation in vitro when measured by [3H]-thymidine. The synthetic methylated DNA CpG ODN but not an unmethylated CpG ODN sequence was shown to promote FoxP3 expression in human CD4+ T cells in the presence of TGF beta and IL-2. The induction of FoxP3+ suppressor cells is dose dependent and offers a potential clinical therapeutic application in allergic and autoimmune and inflammatory diseases. CONCLUSION: The use of this methylated CpG ODN offers a broad clinical application as a novel therapeutic method for Treg induction and, because of its low cost and small size, should facilitate delivery via nasal, respiratory, gastrointestinal routes, and/or by injection, routes of administration important for vaccine delivery to target sites responsible for respiratory, gastrointestinal, and systemic forms of allergic and autoimmune disease.

Inflammation negatively regulates FOXP3 and regulatory T-cell function via DBC1.

Forkhead box P3 (FOXP3)-positive Treg cells are crucial for maintaining immune homeostasis. FOXP3 cooperates with its binding partners to elicit Treg cells' signature and function, but the molecular mechanisms underlying the modulation of the FOXP3 complex remain unclear. Here we report that Deleted in breast cancer 1 (DBC1) is a key subunit of the FOXP3 complex. We found that DBC1 interacts physically with FOXP3, and depletion of DBC1 attenuates FOXP3 degradation in inflammatory conditions. Treg cells from Dbc1-deficient mice were more resistant to inflammation-mediated abrogation of Foxp3 expression and function and delayed the onset and severity of experimental autoimmune encephalomyelitis and colitis in mice. These findings establish a previously unidentified mechanism regulating FOXP3 stability during inflammation and reveal a pathway for potential therapeutic modulation and intervention in inflammatory diseases.

Follistatin-like 1 protects cardiomyoblasts from injury induced by sodium nitroprusside through modulating Akt and Smad1/5/9 signaling.

Cardiac cell apoptosis provoked by excessive sodium nitroprusside (SNP) toxicity, a potent vasodilator, limited its clinical application. Effective means for protection against SNP-induced cardiotoxicity would be highly needed. This study investigated the effects of Follistatin-like 1 (FSTL1) on the injury induced by SNP in rat cardiomyoblast H9c2 cells. First, expression of FSTL is attenuated following SNP treatment. SNP challenge significantly increases cardiac cell death, which is attenuated by FSTL1 pretreatment. Additionally, knockdown of endogenous FSTL1 enhances SNP-induced cell apoptosis. Furthermore, FSTL1 pretreatment partially inhibits SNP-induced NO generation. LY294002 and BMP4 completely abolish cytoprotective role of FSTL1 against SNP challenge, indicating both activation of Akt and inhibition of BMP/Smad1/5/9 signaling are involved in this cellular process. Lastly, FSTL1-mediated cytoprotection is independent of Smad2/3 signaling, as SB525334 fails to remove its protective role. Taken together, these results indicated that FSTL1 protects the SNP-induced injury in cardiac H9c2 cells through, at least in part, the activation of Akt and inhibition of Smad1/5/9 signaling.