Expression analysis of inhibitory B7 family members in Alzheimer's disease.

Alzheimer's disease (AD) is a global health problem due to its complexity, which frequently makes the development of treatment methods extremely difficult. Therefore, new methodologies are necessary to investigate the pathophysiology of AD and to treat AD. The interaction of immune modulation and neurodegeneration has added new dimensions in current knowledge of AD etiology and offers an attractive opportunity for the discovery of novel biomarkers and therapies. Using quantitative polymerase chain reaction, we compared the expression levels of inhibitory B7 family members (B7-1, B7-2, B7-H1, B7-DC, B7-H3, B7-H4, B7-H5, B7-H7, and ILDR2), as immune regulators, in the peripheral blood of late-onset AD (LOAD) patients (n = 50) and healthy individuals (n = 50). The levels of B7-2, B7-H4, ILDR2, and B7-DC expression were significantly higher in-patient blood samples than in control blood samples. Furthermore, we discovered a substantial positive correlation between all gene expression levels. In addition, the current study indicated that ILDR2, B7-H4, B7-2, and B7-DC might serve as diagnostic biomarkers to identify LOAD patients from healthy persons. The present work provides additional evidence for the significance of inhibitory B7 family members to the etiology of LOAD.

Exosomal B7-H4 from irradiated glioblastoma cells contributes to increase FoxP3 expression of differentiating Th1 cells and promotes tumor growth.

BACKGROUND: Glioblastoma (GBM) is the most common and aggressive form of primary brain tumor. Although numerous postoperative therapeutic strategies have already been developed, including radiotherapy, tumors inevitably recur after several years of treatment. The coinhibitory molecule B7-H4 negatively regulates T cell immune responses and promotes immune escape. Exosomes mediate intercellular communication and initiate immune evasion in the tumor microenvironment (TME). OBJECTIVE: This study aimed to determine whether B7-H4 is upregulated by radiation and loaded into exosomes, thus contributing to immunosuppression and enhancing tumor growth. METHODS: Iodixanol density-gradient centrifugation and flow cytometry were used to verify exosomal B7-H4. Naïve T cells were differentiated into Th1 cells, with or without exosomes. T cell-secreted cytokines and markers of T cell subsets were measured. Mechanistically, the roles of B7-H4, and ALIX in GBM were analyzed using databases and tissue samples. Co-immunoprecipitation, and pull-down assays were used to tested the direct interactions between ATM and ALIX or STAT3. In vitro ATM kinase assays, western blotting, and site-directed mutation were used to assess ATM-mediated STAT3 phosphorylation. Finally, the contribution of exosomal B7-H4 to immunosuppression and tumor growth was investigated in vivo. RESULTS: Exosomes from irradiated GBM cells decreased the anti-tumor immune response of T cell in vitro and in vivo via delivered B7-H4. Mechanistically, irradiation promoted exosome biogenesis by increasing the ATM-ALIX interaction. Furthermore, the ATM-phosphorylated STAT3 was found to directly binds to the B7-H4 promoter to increase its expression. Finally, the radiation-induced increase in exosomal B7-H4 induced FoxP3 expression during Th1 cell differentiation via the activated STAT1 pathway. In vivo, exosomal B7-H4 decreased the radiation sensitivity of GBM cells, and reduced the survival of GBM mice model. CONCLUSION: This study showed that radiation-enhanced exosomal B7-H4 promoted immunosuppression and tumor growth, hence defining a direct link between irradiation and anti-tumor immune responses. Our results suggest that co-administration of radiotherapy with anti-B7-H4 therapy could improve local tumor control and identify exosomal B7-H4 as a potential tumor biomarker.

Altered Levels of Negative Costimulatory Molecule V-Set Domain-Containing T-Cell Activation Inhibitor-1 (VTCN1) and Metalloprotease Nardilysin (NRD1) are Associated with Generalized Active Vitiligo.

BACKGROUND: Vitiligo is characterized by depigmented macules on the skin caused due to autoimmune destruction of melanocytes. V-set domain-containing T-cell activation inhibitor-1 (VTCN1) is a negative costimulatory molecule that plays a vital role in suppressing autoimmunity and tuning immune response. Nardilysin (NRD1), a metalloproteinase, cleaves membrane-tethered VTCN1 resulting in the shedding of soluble-VTCN1 (sVTCN1). However, the role of VTCN1 and NRD1 in vitiligo pathogenesis is unexplored. OBJECTIVES AND METHODS: This study was aimed to (i) Investigate the association of VTCN1 intronic polymorphisms (rs10923223 T/C and rs12046117 C/T) with vitiligo susceptibility in Gujarat population by using Polymerase Chain Reaction- Restriction Fragment Length Polymorphism (PCR-RFLP) (ii) Estimate VTCN1 & NRD1 transcript levels from peripheral blood mononuclear cells (PBMCs) and skin samples of vitiligo patients by real-time PCR, (iii) Estimate sVTCN1 and NRD1 protein levels from plasma by ELISA and (iv) Estimate VTCN1 protein levels in the skin samples of vitiligo patients by immunofluorescence. RESULTS: The analysis revealed increased VTCN1 and NRD1 transcript levels in the skin (p = .039, p = .021 respectively), increased sVTCN1 and NRD1 levels (p = .026, p = .015 respectively) in the plasma, and decreased VTCN1 protein levels (p = .0002) in the skin of vitiligo patients as compared to healthy controls. The genetic analysis revealed no significant association of VTCN1 intronic polymorphisms rs10923223 T/C and rs12046117 C/T with vitiligo susceptibility in Gujarat population (p = .359, p = .937, respectively). CONCLUSIONS: The present study revealed altered VTCN1 and NRD1 expressions in the blood and skin of vitiligo patients, suggesting their potential role in the development and progression of Vitiligo.

Aryl Hydrocarbon Receptor Directly Regulates VTCN1 Gene Expression in MCF-7 Cells.

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that mediates the toxicity of dioxins and polycyclic aromatic hydrocarbons. Recent studies have suggested that AhR is involved in cancer immunity. In the present study, we examined whether AhR regulates the expression of immune checkpoint genes in breast cancer cells. We discovered that the mRNA expression of V-set domain containing T cell activation inhibitor 1 (VTCN1) that negatively regulates T cell immunity was upregulated by AhR agonists in breast cancer cell lines, MCF-7 and T47D. Furthermore, AhR knockout or knockdown experiments clearly demonstrated that upregulation of VTCN1 gene expression by 3-methylcholanthrene was AhR dependent. Luciferase reporter and chromatin immunoprecipitation assays revealed that this upregulation of VTCN1 gene expression was induced by the recruitment of AhR to the AhR responsive element in the VTCN1 gene promoter in MCF-7 cells. Taken together, AhR directly regulates VTCN1 gene expression in MCF-7 cells.

Silencing of B7-H4 induces intracellular oxidative stress and inhibits cell viability of breast cancer cells via downregulating PRDX3.

Breast cancer (BC) is the most common malignancy in women worldwide, accounting for 15.5% of total cancer deaths. B7-H4 belongs to the B7 family members and plays an important role in the development of a variety of cancers, while Peroxiredoxin III (PRDX3) is an antioxidant protein found in mitochondria. Aberrant expression of B7-H4 or PRDX3 has been implicated in the tumorigenesis of various cancers. However, the functional roles of B7-H4 and PRDX3 in BC and the underlying mechanisms remain unclear. In this research, we found that silencing of B7-H4 by siRNA could lead to not only cell viability inhibition but also the downregulation of PRDX3 in MCF-7 and T47D cells. In order to reveal the roles of PRDX3 in the B7-H4 pathway, we firstly transfected siRNA specifically targeting PRDX3 into MCF-7 and T47D cells, and the results showed that silencing of PRDX3 also inhibited the viability of MCF-7 and T47D cells significantly, accompanied by the increase of reactive oxygen species (ROS) levels. Then we overexpressed the expression of PRDX3 by transfecting PRDX3 expression plasmids into B7-H4 knocking-down cells of MCF-7 and T47D. The results showed that compared with the control groups (MCF-7 or T47D/siNC+pcDNA3.1 vector), cell viabilities were significantly inhibited in RNAi groups (MCF-7 or T47D/siB7-H4+pcDNA3.1 vector), and mildly inhibited in revertant groups (MCF-7 or T47D/siB7-H4+pcDNA3.1 PRDX3), meanwhile, ROS levels significantly elevated in RNAi groups and had no significant changes in revertant groups. All these results indicate that silencing of B7-H4 increases intracellular ROS levels and affects cell viability by modulating the expression of PRDX3 in BC cells, which may provide a potential strategy and therapeutic target for the treatment of BC.

Silencing of B7H4 Represses the Development of Oral Squamous Cell Carcinoma Through Promotion of M1 Macrophage Polarization.

PURPOSE: Tumor-associated macrophages can support oral squamous cell carcinoma (OSCC) progression, and overexpression of the immunomodulator B7H4 correlates with poor prognosis of OSCC patients. We performed this study to assess the effect of B7H4 silencing on macrophage polarization and explore the potential mechanism of B7H4 during OSCC progression. METHODS: Short hairpin RNA targeting B7H4 was used to knock down B7H4. The predictor variable was B7H4 expression level, and the outcome variables were SCC9 cell growth and metastasis, M1/M2 macrophage ratio, and anti-programmed death-1 (PD-1)/STAT3 pathway-related protein levels. These were measured through real-time qPCR, Western blot analysis, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MTT), 5-ethynyl-2'-deoxyuridine assay, and transwell assay. In addition, a tumor xenograft mouse model was used to examine the effect of B7H4 silencing (+/- Colivelin, an activator of STAT3) on tumor growth and macrophage polarization. RESULTS: The expression of B7H4 in OSCC cell lines was more than 2-fold compared with that in human normal oral keratinocytes via real-time qPCR and Western blot analysis. Knockdown of B7H4 repressed the proliferation, migration, and invasion of SCC9 cells, which were detected by 5-ethynyl-2'-deoxyuridine and transwell assay, as well as reduced PD-1/STAT3 pathway-related protein levels, promoted M1 macrophage polarization, and inhibited M2 polarization. In vivo research demonstrated that B7H4 silencing also inhibited the growth of tumor xenograft and increased the M1/M2 ratio in an OSCC mouse model. Colivelin reversed the inhibitory effects of B7H4 knockdown on OSCC progression and reversed macrophage polarization both in vitro and in vivo. CONCLUSIONS: B7H4 is upregulated during OSCC progression. Its downregulation may promote M1 macrophage polarization and inhibit M2 macrophage polarization via deactivating the PD-1/STAT3 pathway, thus restraining OSCC development.

B7-H4 expression promotes non-small cell lung cancer progression via AMPK/mTOR signaling.

Several studies have demonstrated that B7-H4 is highly expressed in a variety of cancers and often affects tumor development. However, its role in cancer stemness and epithelial-to-mesenchymal transition (EMT) in non-small cell lung cancer (NSCLC) has not been reported. Here, we investigated the relationship between B7-H4 expression and cancer stemness and EMT by immunohistochemistry in 106 NSCLC tissues obtained from patients. The results confirmed that B7-H4 is highly expressed in NSCLC tissues and closely correlated with the expression of EMT-related proteins (Snail, Vimentin) and cancer stemness-related proteins (SOX2, SOX9, and CD44). Immunofluorescence assay indicated that B7-H4 colocalized with SOX2 and SOX9 in the nuclei of NSCLC cells. Additionally, upon knocking down B7-H4, the expression of SOX2, SOX9, and CD44, as well as of Snail and Vimentin was inhibited, whereas E-cadherin expression was enhanced in NSCLC cells. Meanwhile, inhibiting the expression of B7-H4 resulted in reduced invasion and migration ability of NSCLC cells. Mechanistically, silencing B7-H4 activated the adenosine monophosphate-activated protein kinase /mammalian target of rapamycin signaling, which in turn, negatively regulated cell proliferation, stemness, and migration. In conclusion, our results suggest that B7-H4 expression is high in NSCLC tissues, and it has an effect on EMT and cancer stemness. This further suggests that B7-H4 has a potential role in promoting the progression of NSCLC and thereby could be a potential therapeutic target in NSCLC treatment.

Elevated expression of B7 homolog 4 is associated with disease progression in upper urinary tract urothelial carcinoma.

BACKGROUND: B7 homolog 4 (B7-H4) is a negative regulator of immune responses, but its immunoregulatory role in the tumor microenvironment of upper urinary tract urothelial carcinoma (UTUC) remains unclear. METHODS: We measured the immunohistochemical expression of B7-H4, CD8 and T cell intracellular antigen 1 (TIA-1), a marker of activated CD8, in 133 patients with UTUC who underwent nephroureterectomy. We also studied the relationship between B7-H4, CD8 and TIA-1 expression and clinicopathological characteristics. RESULTS: B7-H4 was mainly expressed on the surface in tumor cells, while CD8 and TIA-1 were often expressed in tumor-infiltrating lymphocytes. Elevated expression of B7-H4 in tumor cells was associated with a poorer histological grade, higher pT stage, regional lymph node metastasis, lymphovascular invasion, poorer response of recurrent metastatic lesions to systemic chemotherapy and shorter overall survival. Expression of CD-8 or TIA-1 alone did not correlate directly with clinicopathological characteristics, but among the patients with higher B7-H4 expression in the primary tumors, those with higher CD8 or TIA-1 expression had a better response to systemic chemotherapy, and longer survival, than these with lower CD8 or TIA-1 expression. Cox multivariate regression analysis revealed that higher expression of B7-H4 was associated with shorter overall survival. CONCLUSIONS: These findings suggest that B7-H4 expression in the tumor microenvironment influences the progression of UTUC through cancer immunity and metabolic activity. Tumor cell-associated B7-H4 might be a potential target for cancer immunotherapies.

The immunogenomic landscape of resected intrahepatic cholangiocarcinoma.

BACKGROUND AND AIMS: Cholangiocarcinoma (CCA) is a deadly and highly therapy-refractory cancer of the bile ducts, with early results from immune checkpoint blockade trials showing limited responses. Whereas recent molecular assessments have made bulk characterizations of immune profiles and their genomic correlates, spatial assessments may reveal actionable insights. APPROACH AND RESULTS: Here, we have integrated immune checkpoint-directed immunohistochemistry with next-generation sequencing of resected intrahepatic CCA samples from 96 patients. We found that both T-cell and immune checkpoint markers are enriched at the tumor margins compared to the tumor center. Using two approaches, we identify high programmed cell death protein 1 or lymphocyte-activation gene 3 and low CD3/CD4/inducible T-cell costimulator specifically in the tumor center as associated with poor survival. Moreover, loss-of-function BRCA1-associated protein-1 mutations are associated with and cause elevated expression of the immunosuppressive checkpoint marker, B7 homolog 4. CONCLUSIONS: This study provides a foundation on which to rationally improve and tailor immunotherapy approaches for this difficult-to-treat disease.

Mifepristone inhibited the expression of B7-H2, B7-H3, B7-H4 and PD-L2 in adenomyosis.

BACKGROUND: The immune mechanism was shown to be involved in the development of adenomyosis. The aim of the current study was to evaluate the expression of the immune checkpoints B7-H2, B7-H3, B7-H4 and PD-L2 in adenomyosis and to explore the effect of mifepristone on the expression of these immune checkpoints. METHODS: The expression of B7-H2, B7-H3, B7-H4 and PD-L2 in normal endometria and adenomyosis patient samples treated with or without mifepristone was determined by immunohistochemistry analysis. RESULTS: In adenomyosis patient samples, the expression of B7-H2, B7-H3 and B7-H4 was increased in the eutopic and ectopic endometria compared with normal endometria, both in the proliferative and secretory phases. Moreover, the expression of B7-H2 and B7-H3 was higher in adenomyotic lesions than in the corresponding eutopic endometria, both in the proliferative and secretory phases. The expression of PD-L2 was higher in adenomyotic lesions than in normal endometria in both the proliferative and secretory phases. In the secretory phase but not the proliferative phase, the expression of B7-H4 and PD-L2 in adenomyotic lesions was significantly higher than that in the corresponding eutopic endometria. In normal endometria and eutopic endometria, the expression of B7-H4 was elevated in the proliferative phase compared with that in the secretory phase, while in the ectopic endometria, B7-H4 expression was decreased in the proliferative phase compared with the secretory phase. In addition, the expression of B7-H2, B7-H3, B7-H4 and PD-L2 was significantly decreased in adenomyosis tissues after treatment with mifepristone. CONCLUSIONS: The expression of the immune checkpoint proteins B7-H2, B7-H3, B7-H4 and PD-L2 is upregulated in adenomyosis tissues and is downregulated with mifepristone treatment. The data suggest that B7 immunomodulatory molecules are involved in the pathophysiology of adenomyosis.

Granulocyte-Macrophage Colony-Stimulating Factor-Activated Neutrophils Express B7-H4 That Correlates with Gastric Cancer Progression and Poor Patient Survival.

Neutrophils are prominent components of gastric cancer (GC) tumors and exhibit distinct phenotypes in GC environment. However, the phenotype, regulation, and clinical relevance of neutrophils in human GC are presently unknown. Here, immunohistochemistry, real-time PCR, and flow cytometry analyses were performed to examine levels and phenotype of neutrophils in samples from 41 patients with GC, and also isolated, stimulated, and/or cultured neutrophils for in vitro regulation assays. Finally, we performed Kaplan-Meier plots for overall survival by using the log-rank test to evaluate the clinical relevance of neutrophils and their subsets. In our study, neutrophils in tumor tissues were significantly higher than those in nontumor tissues and were positively associated with tumor progression but negatively correlated with GC patient survival. Most intratumoral neutrophils showed an activated CD54+ phenotype and expressed high-level immunosuppressive molecule B7-H4. Tumor tissue culture supernatants from GC patients induced neutrophils to express CD54 and B7-H4 in both time-dependent and dose-dependent manners. Locally enriched CD54+ neutrophils and B7-H4+ neutrophils positively correlated with increased granulocyte-macrophage colony-stimulating factor (GM-CSF) detection ex vivo, and in vitro GM-CSF induced the expression of CD54 and B7-H4 on neutrophils in a time-dependent and dose-dependent manner. Moreover, GC tumor-derived GM-CSF activated neutrophils and induced neutrophil B7-H4 expression via Janus kinase (JAK)-signal transducer and activator of transcription 3 (STAT3) signaling pathway activation. Furthermore, higher intratumoral B7-H4+ neutrophil percentage/number was found in GC patients with advanced tumor node metastasis stage and reduced overall survival following surgery. Our results illuminate a novel regulating mechanism of B7-H4 expression on tumor-activated neutrophils in GC, suggesting that functional inhibition of these novel GM-CSF-B7-H4 pathways may be a suitable therapeutic strategy to treat the immune tolerance feature of GC.

B7-H4 induces epithelial-mesenchymal transition and promotes colorectal cancer stemness.

B7-H4 is a unique negative regulator of T cells that is typically significantly overexpressed in various carcinomas and is associated with poor prognosis. However, the effects of B7-H4 expression on epithelial-mesenchymal transition (EMT) and cancer stemness of colorectal cancer (CRC) are not entirely clear. In the present study, we used tissue samples from 98 patients with CRC and CRC cell lines to determine the clinicopathological significance of B7-H4 in CRC and its effects on CRC stemness. We performed immunohistochemical staining; immunofluorescence imaging; western blotting; and tumor sphere formation, wound healing, transwell migration, and in vivo tumorigenesis assays. B7-H4 expression was upregulated in CRC tissues and was associated with lymph node metastasis, distant metastasis, clinical stage, a shorter overall survival rate, and disease-free survival rate. Cox regression analyses indicated that B7-H4 is an independent poor prognostic factor for CRC. In addition, B7-H4 expression was correlated with the expression of EMT-related proteins and cancer stemness-related proteins. Moreover, immunohistochemical and immunofluorescence analyses revealed that B7-H4 was correlated with CD133 and CD44 expression levels in both CRC tissues and HT29 and HCT116 cell lines. Conversely, B7-H4 knockdown downregulated the expression of EMT- and cancer stemness-related proteins, while inhibiting tumor spheroid formation, cell migration, and invasion of CRC cell lines. These results indicate that B7-H4 can promote EMT and may be a novel stem cell marker, suggesting its potential as a prognostic biomarker for CRC.

miRNA-506-3p Directly Regulates rs10754339 (A/G) in the Immune Checkpoint Protein B7-H4 in Breast Cancer.

BACKGROUND: B7-H4 is a novel immune checkpoint protein that negatively regulates T cell activation and function. It is overexpressed in many malignant tumors, including Breast Cancer (BC). It was reported that the presence of the single nucleotide polymorphism rs10754339 (A/G) within the 3' UTR of the B7-H4 gene has a great influence on the risk and progression of BC as well as lymph node metastasis. On the other hand, mounting evidence demonstrated the potential of miR-506-3p to be employed in the diagnosis and treatment of a wide range of human malignancies. It is frequently down-regulated in BC despite its tumor suppressor role. Moreover, Myc, E2F and Rb proteins are key players in cell cycle regulation. In BC, the CDK-RB-E2F axis is extensively deregulated by several genetic mutations. Additionally, the potent proto-oncogene Myc is highly expressed in BC. AIM: The main aims of the study were to investigate the potential role of miR-506-3p in the regulation of B7-H4 SNP rs10754339 (A/G) in BC and to uncover the influence of miR-506-3p on cell cycle and tumor progression in BC cell lines. METHODS: This study employed different BC cell lines, including MDA-MB-231 and MCF7 cells. Several bioinformatics analysis was performed to identify the miRNA that could potentially target B7-H4 SNP rs10754339 (A/G). To confirm the binding Relative luciferase activity was measured using Dual Luciferase Reporter Assay. Transfection experiments were performed using miR-506-3p oligonucleotides using lipofection technique. Furthermore, vital cell cycle regulatory proteins such as cMyc, Rb, and E2F were transfected into BC cells using superfect. Finally, several functional analysis experiments were performed, such as MTT and wound healing assays. RESULTS: miR-506-3p down-regulates the disease-associated rs10754339 "G" allele in B7-H4 gene. It also inhibits cell cycle progression by simultaneously regulating important cell cycle proteins, including RB, E2F and c-Myc. Moreover, miR-506-3p decreased cellular viability and migration capacity of MDA-MB-231 TNBC cells and hormone receptor positive MCF-7 cells. CONCLUSION: miR-506-3p is a potential tumor suppressor miRNA in BC that has a potential role in regulating B7-H4 SNP rs10754339 (A/G).

Comprehensive analysis of a 14 immune-related gene pair signature to predict the prognosis and immune features of gastric cancer.

BACKGROUND: As a new method for predicting tumor prognosis, the predictive effect of immune-related gene pairs (IRGPs) has been confirmed in several cancers, but there is no comprehensive analysis of the clinical significance of IRGPs in gastric cancer (GC). METHOD: Clinical and gene expression profile data of GC patients were obtained from the GEO database. Based on the ImmPort database, differentially expressed immune-related gene (DEIRG) events were determined by a comparison of GC samples and adjacent normal samples. Cox proportional regression was used to construct an IRGP signature, and its availability was validated using three external validation datasets. In addition, we explored the association between clinical data and immune features and established a nomogram to predict outcomes in GC patients. RESULT: A total of 88 DEIRGs were identified in GC from the training set, which formed 3828 IRGPs. Fourteen overall survival (OS)-related IRGPs were used to construct the prognostic signature. As a result, patients in the high-risk group exhibited poorer OS compared to those in the low-risk group. In addition, the fraction of CD8+ T cells, plasma cells, CD4 memory activated T cells, and M1 macrophages was higher in the high-risk group. Expression of two immune checkpoints, CD276 and VTCN1, was significantly higher in the high-risk group as well. Based on the independent prognostic factors, a nomogram was established and showed excellent performance. CONCLUSION: The 14 OS-related IRGP signature was associated with OS, immune cells, and immune checkpoints in GC patients, and it could provide the basis for related immunotherapy.

Inhibition of B7-H4 promotes hepatocellular carcinoma cell apoptosis and autophagy through the PI3K signaling pathway.

B7-H4 and autophagy can regulate or be induced by the PI3K signaling pathway. However, the association between B7-H4 and autophagy in hepatocellular carcinoma (HCC)remains unclear. The aim of this work was to investigate whether B7-H4 regulates autophagy via the PI3K signaling pathway in HCC cells. Here, western blotting was used to measure the expression of the related proteins involved in changes in of autophagy and apoptosis, such as LC3, P62, cleaved caspase 3, cleaved PARP, BCL-2, and BAX in Huh7 and Hep3B cells. Additionally, PI3K/AKT/mTOR signaling pathway proteins were measured. Cell counting kit-8 and flow cytometry were used to analyze the effects of B7-H4 siRNA interference on cell proliferation with the interference of B7-H4 siRNA. We found that B7-H4 siRNA increased HCC cell apoptosis and autophagy, and reduced cell proliferation. Moreover, the apoptosis-related proteins cleaved caspase 3, cleaved PARP and BAX were increased and Bcl-2 was decreased after B7-H4 siRNA interference. The expression level of the autophagy-related protein LC3Ⅱ was upregulated, while expression of the autophagy adaptor P62 expression was decreased in B7-H4 siRNA-pretreated cells. Furthermore, our data revealed that B7-H4 regulated apoptosis and autophagy through the PI3K signaling pathway in HCC cells. Therefore, these results suggested that B7-H4 plays an important role in HCC progression by affecting cell apoptosis and autophagy.

[Knockdown of B7-H4/VTCN1 promotes apoptosis and autophagy of Huh7 cells by inhibiting phosphorylation of JNK].

Objective To investigate the effects of co-stimulatory molecule B7-H4/VTCN1 on apoptosis and autophagy of hepatocellular carcinoma (HCC) cells and the potential signaling pathways. Methods After Huh7 cells were treated by B7-H4 siRNA, CCK-8 assay was used to detect the cell proliferation. Cell apoptosis was measured by flow cytometry. The protein expression levels of cleaved caspase-3 (c-caspase-3), Bcl2, LC3, P62, JNK and phosphorylated JNK (p-JNK) were examined by Western blot analysis. The autophagosome was observed by monodansylcadaverine (MDC) assay. Results After the knockdown of B7-H4, the apoptosis and autophagy of HCC cells increased, and cell proliferation decreased. Moreover, the expression levels of c-caspase-3 and LC3 II went up, while the expression levels of Bcl2 and P62 went down. Furthermore, the phosphorylation of JNK was also inhibited, and autophagosome was visible. Conclusion Knockdown of B7-H4 promotes the apoptosis and autophagy in HCC cells, which may be related to the inhibited phosphorylation of JNK.

Clinical significance of changes in AFP, HTATIP2/TIP30, B7-H4 and inflammatory cytokines after transcatheter arterial chemoembolization.

PURPOSE: To explore the clinical significance of changes in alpha-fetoprotein (AFP), HIV-1 TAT interactive protein 2/TAT interactive protein 30 (HTATIP2/TIP30), B7-H4 and inflammatory cytokines after transcatheter arterial chemoembolization (TACE). METHODS: A total of 84 hepatocellular carcinoma (HCC) patients admitted to the Department of Hepatobiliary Surgery and the Department of Interventional Radiology of our hospital from January 1, 2017 to December 31, 2018 were randomly enrolled and divided into an experimental group and a control group according to treatment methods. The expression levels of AFP mRNA, HTATIP2/TIP30, B7-H4 and inflammatory cytokines were detected before and after treatment, the short-term efficacy was followed up and analyzed, and the correlation between the two was statistically analyzed. RESULTS: The AFP expression level in the two groups of patients was lower after treatment than before treatment, this reduction being more obvious in the experimental group (receiving TACE) than in the control group. Although the levels of serum HTATIP2/TIP30 and B7-H4 were decreased after treatment in both groups, and they were lower after treatment than those before treatment in the control group, lower levels were registered in the control group. Both groups of patients had lower expression levels of tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6) after treatment compared with those before treatment, this decrease being more significant in the experimental group than in the control group. Moreover, the total short-term efficacy rate and the improvement rate of the quality of life were higher in the experimental group than in the control group, although no statistical difference in the survival rate was found between the two groups after 1-year follow-up. The serum level of B7-H4 in the group with good efficacy was lower than in the group with poor efficacy before treatment, and it declined in both groups after treatment, with a lower level in the former than in the latter. Furthermore, the group with good efficacy had a lower level of serum HTATIP2/TIP30 than the group with poor efficacy, while both groups had a decreased level after treatment, with a lower level in the former than in the latter. CONCLUSION: Interventional therapy for primary HCC has good short-term efficacy. It can reduce the levels of serum HTATIP2/TIP30, B7-H4, AFP and inflammation-related indexes, improve the liver function and the patients' quality of life.

Use of a human embryonic stem cell model to discover GABRP, WFDC2, VTCN1 and ACTC1 as markers of early first trimester human trophoblast.

Human placental development during early pregnancy is poorly understood. Many conceptuses are lost at this stage. It is thought that preeclampsia, intrauterine growth restriction and other placental syndromes that manifest later in pregnancy may originate early in placentation. Thus, there is a need for models of early human placental development. Treating human embryonic stem cells (hESCs) with BMP4 (bone morphogenic protein 4) plus A83-01 (ACTIVIN/NODAL signaling inhibitor) and PD173074 (fibroblast growth factor 2 or FGF2 signaling inhibitor) (BAP conditions) induces differentiation to the trophoblast lineage (hESCBAP), but it is not clear which stage of trophoblast differentiation these cells resemble. Here, comparison of the hESCBAP transcriptome to those of trophoblasts from human blastocysts, trophoblast stem cells and placentas collected in the first-third trimester of pregnancy by principal component analysis suggests that hESC after 8 days BAP treatment most resemble first trimester syncytiotrophoblasts. To further test this hypothesis, transcripts were identified that are expressed in hESCBAP but not in cultures of trophoblasts isolated from term placentas. Proteins encoded by four genes, GABRP (gamma-aminobutyric acid type A receptor subunit Pi), WFDC2 (WAP four-disulfide core domain 2), VTCN1 (V-set domain containing T-cell activation inhibitor 1) and ACTC1 (actin alpha cardiac muscle 1), immunolocalized to placentas at 4-9 weeks gestation, and their expression declined with gestational age (R2 = 0.61-0.83). None are present at term. Expression was largely localized to syncytiotrophoblast of both hESCBAP cells and placental material from early pregnancy. WFDC2, VTCN1 and ACTC1 have not previously been described in placenta. These results support the hypothesis that hESCBAP represent human trophoblast analogous to that of early first trimester and are a tool for discovery of factors important to this stage of placentation.

Insulin-like growth factor-1 receptor induces immunosuppression in lung cancer by upregulating B7-H4 expression through the MEK/ERK signaling pathway.

The Insulin-like growth factor-1/Insulin-like growth factor-1 receptor (IGF1/IGF1R) axis contributes to immunosuppression during tumor progression; however, the underlying mechanism remains unclear. In the present study, we found that IGF1 stimulation or IGF1R overexpression (IGF1R-OE) could upregulate the expression of B7-H4, while IGF1R inhibition downregulated B7-H4 in both A549 and SPC-A-1 lung cancer cell lines. IGF1R-OE conferred the inhibition of CD8+ T cells by cancer cells in vitro, and induction of B7-H4 expression was mediated by the activation of the MEK/ERK1/2 signaling pathway. The in vitro findings were further confirmed in vivo using a Lewis lung cancer mouse model. IGF1R-OE promoted tumor growth and inhibited tumor infiltration by CD8+ T cells in the mouse model. However, this effect was suppressed when B7-H4 was knocked down in IGF1R-OE cells. Our findings suggest that IGF1R could induce immunosuppression in lung cancer by upregulating the expression of B7-H4 through the MEK/ERK pathway. B7-H4 may therefore be a potential therapeutic target for lung cancer immunotherapy.