The role of B7-H4 in ovarian cancer immunotherapy: current status, challenges, and perspectives.

Immunotherapy stands as a critical and auspicious therapeutic approach in the fight against cancer nowadays. Immune checkpoint inhibitors, in particular, have garnered widespread employment and delivered groundbreaking therapeutic outcomes across various malignancies. However, the efficacy is unsatisfactory in the ovarian cancer. The pressing concerns of the substantial non-response rate require immediate attention. The pursuit of novel targets and the formulation of synergistic combination therapy approaches are imperative for addressing this challenge. B7-H4, a member of the B7 family of co-inhibitory molecules, exhibits high expression levels in ovarian cancer, correlating closely with tumor progression, drug resistance, and unfavorable prognosis. B7-H4 has the potential to serve as a valuable biomarker for evaluating the immune response of patients. Recent investigations and preclinical trials focusing on B7-H4 in the context of ovarian cancer immunotherapy highlight its emergence as a promising immunotherapeutic target. This review aims to discuss these findings and anticipate the future prospects of leveraging B7-H4 in ovarian cancer immunotherapy and targeted therapy.

Multiplexed Spatial Imaging at the Single-Cell Level Reveals Mutually Exclusive Expression of B7 Family Proteins.

Targeting novel inhibitory ligands beyond anti-PD-1 and PD-L1 and CTLA-4 therapies is essential for the next decade of the immunotherapy era. Agents for the B7 family molecules B7-H3, B7-H4, and B7-H5 are emerging in clinical trial phases; therefore, further accumulation of evidence from both clinical and basic aspects is vital. Here, we applied a 7-color multiplexed imaging technique to analyze the profile of B7 family B7-H3/B7-H4/B7-H5 expression, in addition to PD-L1, and the spatial characteristics of immune cell infiltrates in urothelial carcinoma (UC). The results revealed that B7-H3 and B7-H4 were mainly expressed on tumor cells and B7-H5 on immune cells in UC, and most of the B7-H3/B7-H4/B7-H5-positive cells were mutually exclusive with PD-L1-positive cells. Also, the expression of B7-H4 was elevated in patients with advanced pathologic stages, and high B7-H4 expression was a significant factor affecting overall mortality following surgery in UC. Furthermore, spatial analysis revealed that the distance from the B7-H4+ cells to the nearest CD8+ cells was markedly far compared with other B7 family-positive tumor cells. Interestingly, the distance from B7-H4+ cells to the nearest CD8+ cells was significantly farther in patients dying from cancer after surgery or immune checkpoint inhibitors compared with cancer survivors; thus, high B7-H4 expression in tumor cells may inhibit CD8 infiltration into the tumor space and that B7-H4-positive cells form a specific spatial niche. In summary, we performed a comprehensive evaluation of B7 family member expression and found that the spatial distribution of B7-H4 suggests the potentially useful role of combination blockade with both B7-H4 and the current anti-PD-1/PD-L1 axis in the treatment of UC.

Tuning Immune-Cold Tumor by Suppressing USP10/B7-H4 Proteolytic Axis Reinvigorates Therapeutic Efficacy of ADCs.

Tuning immune-cold tumor hot has largely attracted attention to improve cancer treatment, including immunotherapy and antibody-drug conjugates (ADCs). Utilizing multiomic analyses and experimental validation, this work identifies a pivotal role for the USP10/B7-H4 proteolytic axis in mediating the interplay between tumor immune responses and ADC efficacy, particularly for sacituzumab govitecan (SG) in treating triple negative breast cancers (TNBCs). Mechanistically, the inhibition of autocrine motility factor receptor (AMFR)-mediated ubiquitylation of B7-H4 by the deubiquitinase USP10 leads to the stabilization of B7-H4, which suppresses tumor immune activity and reduces SG treatment effectiveness. Pharmacological inhibition of USP10 promotes the degradation of B7-H4, enhancing tumor immunogenicity and consequently improving the tumor-killing efficacy of SG. In preclinical TNBC models, suppression of USP10/B7-H4 proteolytic axis is effective in increasing SG killing efficacy and reducing tumor growth, especially for the tumors with the USP10high/B7-H7high signature. Collectively, these findings uncover a novel strategy for targeting the immunosuppressive molecule B7-H4 for cancer therapy.

Impact of the Immunomodulatory Factor Soluble B7-H4 in the Progress of Preeclampsia by Inhibiting Essential Functions of Extravillous Trophoblast Cells.

A key aspect of preeclampsia pathophysiology is the reduced invasiveness of trophoblasts and the impairment of spiral artery remodelling. Understanding the causes of altered trophoblast function is critical to understand the development of preeclampsia. B7-H4, a checkpoint molecule, controls a wide range of processes, including T-cell activation, cytokine release, and tumour progression. Our previous findings indicated that B7-H4 levels are elevated in both maternal blood and placental villous tissue during the early stages of preeclampsia. Here, we investigated the function of B7-H4 in trophoblast physiology. Recombinant B7-H4 protein was used to treat human SGHPL-5 extravillous trophoblast cells. Biological functions were investigated using MTT, wound healing, and transwell assays. Signalling pathways were analysed by immunoblotting and immunofluorescence. The functionality of B7-H4 was further confirmed by immunoblotting and immunohistochemical analysis in placental tissues from control and preeclamptic patients following therapeutic plasma exchange (TPE) or standard of care treatment. This study showed that B7-H4 inhibited the proliferation, migration, and invasion capacities of SGHPL-5 extravillous cells while promoting apoptosis by downregulating the PI3K/Akt/STAT3 signalling pathway. These results were consistently confirmed in placental tissues from preterm controls compared to early-onset preeclamptic placental tissues from patients treated with standard of care or TPE treatment. B7-H4 may play a role in the development of preeclampsia by inhibiting essential functions of extravillous trophoblast cells during placental development. One possible mechanism by which TPE improves pregnancy outcomes in preeclampsia is through the elimination of B7-H4 amongst other factors.

Differential Immune Checkpoint Protein Expression in HNSCC: The Role of HGF/MET Signaling.

Although inhibitors targeting the PD1/PD-L1 immune checkpoint are showing comparably good outcomes, a significant percentage of head and neck squamous cell carcinoma (HNSCC) patients do not respond to treatment. Apart from using different treatment strategies, another possibility would be to target other immune checkpoints operating in these non-responding tumors. To obtain an overview of which checkpoint ligands are expressed on HNSCC tumor cells and if these ligands are affected by HGF/MET signaling, we used mRNA sequencing and antibody-based techniques for identifying checkpoint ligands in six HNSCC tumor cell lines. Furthermore, we compared our results to mRNA sequencing data. From the checkpoint ligands we investigated, VISTA was expressed the highest at the RNA level and was also the most ubiquitously expressed. PD-L2 and B7-H3 were expressed comparably lower and were not present in all cell lines to the same extent. B7-H4, however, was only detectable in the Detroit 562 cell line. Concerning the effect of HGF on the ligand levels, PD-L2 expression was enhanced with HGF stimulation, whereas other checkpoint ligand levels decreased with stimulation. B7-H4 levels in the Detroit 562 cell line drastically decreased with HGF stimulation. This is of interest because both the checkpoint ligand and the growth factor are reported to be connected to epithelial-mesenchymal transition in the literature.

B7H4 Role in Solid Cancers: A Review of the Literature.

Anti-cancer immunotherapies entirely changed the therapeutic approach to oncological patients. However, despite the undeniable success of anti-PD-1, PD-L1, and CTLA-4 antibody treatments, their effectiveness is limited either by certain types of malignancies or by the arising problem of cancer resistance. B7H4 (aliases B7x, B7H4, B7S1, VTCN1) is a member of a B7 immune checkpoint family with a distinct expression pattern from classical immune checkpoint pathways. The growing amount of research results seem to support the thesis that B7H4 might be a very potent therapeutic target. B7H4 was demonstrated to promote tumour progression in immune "cold" tumours by promoting migration, proliferation of tumour cells, and cancer stem cell persistence. B7H4 suppresses T cell effector functions, including inflammatory cytokine production, cytolytic activity, proliferation of T cells, and promoting the polarisation of naïve CD4 T cells into induced Tregs. This review aimed to summarise the available information about B7H4, focusing in particular on clinical implications, immunological mechanisms, potential strategies for malignancy treatment, and ongoing clinical trials.

Progestogen-driven B7-H4 contributes to onco-fetal immune tolerance.

Immune tolerance mechanisms are shared in cancer and pregnancy. Through cross-analyzing single-cell RNA-sequencing data from multiple human cancer types and the maternal-fetal interface, we found B7-H4 (VTCN1) is an onco-fetal immune tolerance checkpoint. We showed that genetic deficiency of B7-H4 resulted in immune activation and fetal resorption in allogeneic pregnancy models. Analogously, B7-H4 contributed to MPA/DMBA-induced breast cancer progression, accompanied by CD8+ T cell exhaustion. Female hormone screening revealed that progesterone stimulated B7-H4 expression in placental and breast cancer cells. Mechanistically, progesterone receptor (PR) bound to a newly identified -58 kb enhancer, thereby mediating B7-H4 transcription via the PR-P300-BRD4 axis. PR antagonist or BRD4 degrader potentiated immunotherapy in a murine B7-H4+ breast cancer model. Thus, our work unravels a mechanistic and biological connection of a female sex hormone (progesterone) to onco-fetal immune tolerance via B7-H4 and suggests that the PR-P300-BRD4 axis is targetable for treating B7-H4+ cancer.

The deubiquitinase USP2a promotes tumor immunosuppression by stabilizing immune checkpoint B7-H4 in lung adenocarcinoma harboring EGFR-activating mutants.

B7-H4 is an immune checkpoint crucial for inhibiting CD8+ T-cell activity. A clinical trial is underway to investigate B7-H4 as a potential immunotherapeutic agent. However, the regulatory mechanism of B7-H4 degradation via the ubiquitin-proteasome pathway (UPP) remains poorly understood. In this study, we discovered that proteasome inhibitors effectively increased B7-H4 expression, while EGFR-activating mutants promoted B7-H4 expression through the UPP. We screened B7-H4 binding proteins by co-immunoprecipitation and mass spectrometry and found that USP2a acted as a deubiquitinase of B7-H4 by removing K48- and K63-linked ubiquitin chains from B7-H4, leading to a reduction in B7-H4 degradation. EGFR mutants enhanced B7-H4 stability by upregulating USP2a expression. We further investigated the role of USP2a in tumor growth in vivo. Depletion of USP2a in L858R/LLC cells inhibited tumor cell proliferation, consequently suppressing tumor growth in immune-deficient nude mice by destabilizing downstream molecules such as Cyclin D1. In an immune-competent C57BL/6 mouse tumor model, USP2a abrogation facilitated infiltration of CD95+CD8+ effector T cells and hindered infiltration of Tim-3+CD8+ and LAG-3+CD8+ exhausted T cells by destabilizing B7-H4. Clinical lung adenocarcinoma samples showed a significant correlation between B7-H4 abundance and USP2a expression, indicating the contribution of the EGFR/USP2a/B7-H4 axis to tumor immunosuppression. In summary, this study elucidates the dual effects of USP2a in tumor growth by stabilizing Cyclin D1, promoting tumor cell proliferation, and stabilizing B7-H4, contributing to tumor immunosuppression. Therefore, USP2a represents a potential target for tumor therapy.

Aberrant expression of B7-H4 and B7-H5 contributes to the development of cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (CSCC) is the second most common malignant tumor of the skin. B7 homolog 4 (B7-H4) and B7-H5 (B7 homolog 5) are associated with a variety of tumors. Investigate the potential role of B7-H4 and B7-H5 in regulating the tumorigenesis and progression of CSCC. B7-H4 and B7-H5 transcriptome data were collected from GEO and TCGA databases and subjected to bioinformatical analysis by protein-protein interaction (PPI) network, functional enrichment analysis, immune analysis, and drug-gene interaction prediction analysis. We characterized the expression of B7-H4 and B7-H5 in carcinoma tissues of CSCC patients by immunohistochemistry. Meanwhile, the clinical correlation of B7-H4 and B7-H5 in CSCC was explored by statistical analysis. B7-H4 and B7-H5 genes were under-expressed in CSCC and correlated with tumor staging. According to GO and KEGG Pathway enrichment analysis, B7-H4, and B7-H5 can regulate the proliferation and activation of T cells, lymphocytes, and monocytes, and the expression of cytokines, such as IL-6 and IL-10, in CSCC. B7-H4 and B7-H5 are also jointly involved in the occurrence and development of CSCC via the JAK-STAT and Notch signaling pathways. We found that B7-H4 and B7-H5 proteins were abnormally highly expressed in CSCC tissue and correlated with tumor size and stage. Our findings offer new insights into the pathogenesis of CSCC and suggest that B7-H4 and B7-H5 are novel tissue biomarkers and promising therapeutic targets for CSCC.

Dehydroepiandrosterone attenuated the immune escape of oral squamous cell carcinoma through NF-κB p65/miR-15b-5p/B7-H4 axis.

OBJECTIVES: We aimed to explore the effects and mechanisms of action of dehydroepiandrosterone (DHEA) on immune evasion of oral squamous cell carcinoma (OSCC) to provide evidence for enhancing the effect of immunotherapy. MATERIALS AND METHODS: A xenograft mouse model and immunohistochemistry were used to reveal the patterns of tumor-infiltrating lymphocytes (TILs). The CAL27 and SCC VII cell lines were used for the in vitro study. Western blotting, qPCR, immunofluorescence, and flow cytometry were used to evaluate the expression of B7-H4. Recombinant mouse B7-H4 protein (rmB7-H4) and PG490, an inhibitor of NF-κB p65 were used for the "rescue study." Gain- and loss-of-function, luciferase reporter, and chromatin immunoprecipitation assays were performed to verify this mechanism. RESULTS: DHEA inhibited tumor growth in an OSCC xenograft mouse model, increased CD8 + cells, and decreased FOXP3 + cells in TILs. DHEA reduced the expression of B7-H4 in CAL27 and SCC VII cells RmB7-H4 reverses the effect of DHEA on tumor growth and TIL patterns. DHEA increased the expression of miR-15b-5p and activated its transcriptional factor NF-κB p65. Further experiments demonstrated that miR-15b-5p inhibited B7-H4 expression by binding to its 3'-UTR regions, and NF-κB p65 activated miR-15b transcription. PG490 reversed the effects of DHEA on tumor growth, antitumor immunity in the OSCC xenograft model, and the expression/phosphorylation of NF-κB p65, miR-15b-5p, and B7-H4. CONCLUSIONS: This study indicates that DHEA attenuates the immune escape of OSCC cells by inhibiting B7-H4 expression, providing new insights for cancer immunotherapy.

B7-H4 reduces the infiltration of CD8+T cells and induces their anti-tumor dysfunction in gliomas.

B7-H4 is a promising immune checkpoint molecule in tumor immunotherapy. Our previous study showed that high B7-H4 expression was strongly correlated with deficiency in tumor infiltrated lymphocytes (TILs) in glioma patients. On this basis, we investigated the impact of B7-H4 on CD8+TILs in gliomas and the associated molecular mechanism here. B7-H4-positive tumor samples (n=129) from our glioma cohort were used to assess B7-H4 expression and CD8+TIL quantification by immunohistochemistry. CD8+TILs from five glioma patients cultured with B7-H4 protein were used to evaluate anti-tumor dysfunction by flow cytometry and ELISpot. An orthotopic murine glioma model was used to investigate the role of B7-H4 in glioma CD8+TILs by immunohisto- chemistry and flow cytometry. CD8+TILs from glioma patients cultured with B7-H4 protein were used to explore the potential molecular mechanism by RNA sequencing and western blot. Our results showed that glioma CD8+TIL density was negatively correlated with B7-H4 expression both in glioma patient cohort (P < 0.05) and orthotopic glioma murine model (P < 0.01). B7-H4 also lowered the expression of CD137 and CD103 (P < 0.05 for both) in glioma CD8+TILs and reduced their secretion of the anti-tumor cytokines IFN-γ and TNF-α (P < 0.01 for both) in a dose-dependent manner. Furthermore, B7-H4 was found to induce early dysfunction of glioma CD8+TILs by downregulating the phosphorylation of AKT and eNOS (P < 0.05 for both). In conclusion, B7-H4 reduced the infiltration of glioma CD8+TILs and induced an anti-tumor dysfunction phenotype. B7-H4 may also impair the anti-tumor function of glioma CD8+TILs via the AKT-eNOS pathway. These results indicated that B7-H4 may serve as a potential target in future glioma immunotherapy.

Prognostic Value of B7H4 Expression in Patients with Solid Cancers: A Systematic Review and Meta-Analysis.

V-set domain-containing T-cell activation inhibitor 1 (aliases VTCN1, B7H4) participates in tumour immune escape by delivering inhibitory signals to T cells. The purpose of this article was to assess the B7H4 prognostic value in solid cancers. Three databases were searched for relevant articles. The main endpoints were overall survival (OS), disease-specific survival (DSS), progression-free survival (PFS), recurrence-free survival (RFS), and disease-free survival (DFS). Appropriate hazard ratios (HRs) were pooled. The R studio software (version 4.0.3) was used for data analysis. Thirty-one studies met the inclusion criteria. High expression of B7H4 was associated with worse OS (HR = 1.52, 95% CI: 1.37-1.68) but not with DSS (HR = 1.14, 95% CI: 0.49-2.63), RFS (HR = 1.77, 95% CI: 0.75-4.18), DFS (HR = 1.29, 95% CI: 0.8-2.09), or PFS (HR = 1.71, 95% CI: 0.91-3.2) in patients with solid cancers. High expression of B7H4 is associated with a poorer prognosis in patients with solid cancers. B7H4 is a promising prognostic biomarker and immunotherapeutic target for various solid cancers because of its activity in cancer immunity and tumourigenesis.

Interferon-γ in the tumor microenvironment promotes the expression of B7H4 in colorectal cancer cells, thereby inhibiting cytotoxic T cells.

The bioactivity of interferon-γ (IFN-γ) in cancer cells in the tumor microenvironment (TME) is not well understood in the current immunotherapy era. We found that IFN-γ has an immunosuppressive effect on colorectal cancer (CRC) cells. The tumor volume in immunocompetent mice was significantly increased after subcutaneous implantation of murine CRC cells followed by IFN-γ stimulation, and RNA sequencing showed high expression of B7 homologous protein 4 (B7H4) in these tumors. B7H4 promotes CRC cell growth by inhibiting the release of granzyme B (GzmB) from CD8+ T cells and accelerating apoptosis in CD8+ T cells. Furthermore, interferon regulatory factor 1 (IRF1), which binds to the B7H4 promoter, is positively associated with IFN-γ stimulation-induced expression of B7H4. The clinical outcome of patients with CRC was negatively related to the high expression of B7H4 in cancer cells or low expression of CD8 in the microenvironment. Therefore, B7H4 is a biomarker of poor prognosis in CRC patients, and interference with the IFN-γ/IRF1/B7H4 axis might be a novel immunotherapeutic method to restore the cytotoxic killing of CRC cells.

Clinical significance of blocking novel immune checkpoint B7-H4 in urothelial carcinoma of bladder as a potential therapeutic target.

Urothelial Carcinoma of Bladder is complex disease with high mortality and recurrence rates. Current standard regimes have exhibited anti-tumor activity but still, a proportion of patients are non-responsive or in-eligible to receive such treatments. Immune checkpoints have emerged as potential class of therapeutics to be tested in UCB patients. Clinical trials targeting PD-1/PD-L1 axis have been tested in UCB but still a proportion of patients are non-responsive to it which stresses upon identifying new targets. New immune checkpoint B7-H4 has been shown to negatively regulate T cell activity in cancer and is a poor prognostic factor in various solid tumors. In this study we assessed the novel immune checkpoint B7-H4 status in UCB patients. We observed elevated expression of B7-H4 and PD-L1 on CD8+ T cells in circulation of UCB patients. Relative mRNA expression and immunohistochemistry displayed upregulation in bladder tumor tissue. Increased expression of B7-H4 along with PD-L1 in periphery and tumor of UCB patients highlights involvement of B7-H4 in disease progression. Combinatorial blocking of B7-H4 and PD-L1 enhanced IFN-γ and granzyme B in CD8+ T cells functional T cell immune response in UCB patients. Also, B7-H4 was significantly associated with clinico-pathological parameters. Our findings highlight B7-H4 as potential therapeutic target for treatment of UCB patients in future after further validation.

An analysis of placental chorionic villous and decidual basalis tissue immunoreactivity in patients after cesarean section due to a placenta accreta spectrum disorder and elective cesarean section followed by the depressed mood.

An analysis of placental chorionic villous and decidual basalis tissue immunoreactivity in patients after cesarean section due to a placenta accreta spectrum disorder and elective cesarean section followed by a depressed mood. RESEARCH BACKGROUND: Over the past few years, interest in investigating immune dysfunction in patients with psychiatric disorders has increased. B7-H4 is a molecule with immunosuppressive properties that seems to play a key role in establishing maternal tolerance against fetal antigens. The aim of this study was to compare the B7-H4 immunoreactivity levels in patients after cesarean section. METHODS: Placental and decidual tissue samples were obtained from 49 women who delivered at Bielanski Hospital in Warsaw between 2009 and 2015. Fifteen of the patients developed postpartum depression and 14 had a diagnosis of placenta accreta spectrum. The control group consisted of 20 healthy patients on whom cesarean section was performed due to breech presentation at term. RESULTS: The highest levels of B7-H4 immunoreactivity were found in the placental chorionic villous and decidual basalis tissue samples of the patients who later developed postpartum depression, while the lowest levels were found in the samples of those patients with a placenta accreta spectrum disorder. The difference between the B7-H4 immunoreactivity levels of these two groups was statistically significant. The B7-H4 expression levels were statistically significantly higher in the women in the postpartum depression group than in the control group. CONCLUSION: Postpartum depression follows a disturbance of the suppressive milieu responsible for rebalancing the maternal immune system after the initial cytotoxic activation during labor.

Analysis of B7-H4 Expression Across Salivary Gland Carcinomas Reveals Adenoid Cystic Carcinoma-Specific Prognostic Relevance.

B7-H4 (VTCN1), a member of the B7 family, is overexpressed in several types of cancer. Here we investigated the pattern of expression of B7-H4 in salivary gland carcinomas (SGC) and assessed its potential as a prognostic marker and therapeutic target. Immunohistochemistry (IHC) analyses were performed in a cohort of 340 patient tumors, composed of 124 adenoid cystic carcinomas (ACC), 107 salivary duct carcinomas (SDC), 64 acinic cell carcinomas, 36 mucoepidermoid carcinomas (MEC), 9 secretory carcinomas (SC), as well as 20 normal salivary glands (controls). B7-H4 expression was scored and categorized into negative (<5% expression of any intensity), low (5%-70% expression of any intensity or >70% with weak intensity), or high (>70% moderate or strong diffuse intensity). The associations between B7-H4 expression and clinicopathologic characteristics, as well as overall survival, were assessed. Among all tumors, B7-H4 expression was more prevalent in ACC (94%) compared with those of SC (67%), MEC (44%), SDC (32%), and acinic cell carcinomas (0%). Normal salivary gland tissue did not express B7-H4. High expression of B7-H4 was found exclusively in ACC (27%), SDC (11%), and MEC (8%). In SDC, B7-H4 expression was associated with female gender (P = .002) and lack of androgen receptor expression (P = .012). In ACC, B7-H4 expression was significantly associated with solid histology (P < .0001) and minor salivary gland primary (P = .02). High B7-H4 expression was associated with a poorer prognosis in ACC, regardless of clinical stage and histologic subtype. B7-H4 expression was not prognostic in the non-ACC SGC evaluated. Our comparative study revealed distinct patterns of B7-H4 expression according to SGC histology, which has potential therapeutic implications. B7-H4 expression was particularly high in solid ACC and was an independent prognostic marker in this disease but not in the other SGC assessed.

[Effect of miR-125b on T Cell Activation in Aplastic Anemia by Targetting B7-H4].

OBJECTIVE: To investigate the effect of miR-125b on T cell activation in patients with aplastic anemia (AA) and its molecular mechanism. METHODS: A total of 30 AA patients were enrolled in department of hematology, Binzhou Medical University Hospital from January 2018 to October 2021, as well as 15 healthy individuals as healthy control (HC) group. Peripheral blood mononuclear cells (PBMCs) were isolated, in which the levels of miR-125b and B7-H4 mRNA were detected by RT-qPCR. Immunomagnetic beads were used to separate naive T cells and non-naive T cells from AA patients and healthy people to detect the levels of miR-125b and B7-H4 mRNA. Lentivirus LV-NC inhibitor and LV-miR-125b inhibitor were transfected into cells, and T cell activation was detected by flow cytometry. The dual-luciferase reporter gene assay was used to detect the targetting relationship between miR-125b and B7-H4. RT-qPCR and Western blot were used to detect the levels of miR-125b, CD40L, ICOS, IL-10 mRNA and B7-H4 protein. RESULTS: Compared with HC group, the expression of miR-125b was up-regulated but B7-H4 mRNA was down-regulated in PBMCs of AA patients (P <0.05), and the proportions of CD4+CD69+ T cells and CD8+CD69+ T cells in PBMCs of AA patients were higher (P <0.05). The expression of miR-125b was significantly up-regulated but B7-H4 mRNA was down-regulated in both naive T cells and non-naive T cells of AA patients (P <0.05), and non-naive T cells was more significant than naive T cells (P <0.05). Compared with NC inhibitor group, the expression of miR-125b was significantly decreased, the expression level of CD69 on CD4+ and CD8+ T cells in PBMCs was also significantly decreased, while the luciferase activity was significantly increased after co-transfection of miR-125b inhibitor and B7-H4-3'UTR-WT in the miR-125b inhibitor group (P <0.05). Compared with NC inhibitor group, the mRNA and protein levels of B7-H4 were significantly increased in the miR-125b inhibitor group (P <0.05). Compared with miR-125b inhibitor+shRNA group, the expression levels of CD69 on CD4+ and CD8+ T cells were significantly increased, and the levels of CD40L, ICOS and IL-10 mRNA were also significantly increased in the miR-125b inhibitor+sh-B7-H4 group (P <0.05). CONCLUSION: MiR-125b may promote T cell activation by targetting B7-H4 in AA patients.

A SOX9-B7x axis safeguards dedifferentiated tumor cells from immune surveillance to drive breast cancer progression.

How dedifferentiated stem-like tumor cells evade immunosurveillance remains poorly understood. We show that the lineage-plasticity regulator SOX9, which is upregulated in dedifferentiated tumor cells, limits the number of infiltrating T lymphocytes in premalignant lesions of mouse basal-like breast cancer. SOX9-mediated immunosuppression is required for the progression of in situ tumors to invasive carcinoma. SOX9 induces the expression of immune checkpoint B7x/B7-H4 through STAT3 activation and direct transcriptional regulation. B7x is upregulated in dedifferentiated tumor cells and protects them from immunosurveillance. B7x also protects mammary gland regeneration in immunocompetent mice. In advanced tumors, B7x targeting inhibits tumor growth and overcomes resistance to anti-PD-L1 immunotherapy. In human breast cancer, SOX9 and B7x expression are correlated and associated with reduced CD8+ T cell infiltration. This study, using mouse models, cell lines, and patient samples, identifies a dedifferentiation-associated immunosuppression mechanism and demonstrates the therapeutic potential of targeting the SOX9-B7x pathway in basal-like breast cancer.

The Methylation in B7-H4 and BTLA Genes are Associated with the Risk of Pulmonary Tuberculosis.

Background: The important roles of B7 homologous body 4 (B7-H4), B and T lymphocyte attenuator (BTLA) in patients with pulmonary tuberculosis (PTB) have been reported. This study aims to evaluate the association among B7-H4 and BTLA genes polymorphism, methylation and PTB susceptibility. Methodology: Here, we assessed the possible relationship of 10 single nucleotide polymorphisms (SNPs) in B7-H4, BTLA genes with PTB susceptibility in a Chinese population (496 PTB patients and 502 controls) by SNPscan technique. Then, the B7-H4, BTLA genes methylation levels among 98 PTB patients and 97 controls were detected using MethylTarget technique. Results: This study found no significant differences in allele and genotype frequencies of B7-H4 gene rs10754339, rs10801935, rs10923223, rs1937956, rs3738414, BTLA gene rs1982809, rs2971205, rs75368388, rs9288953 variants between PTB patients and controls. Haplotype analysis suggested that the lower frequencies of B7-H4 AATTG haplotype, BTLA GATT haplotype and the higher frequency of BTLA AGTC haplotype were found in PTB patients when compared with controls. We also found that the frequency of BTLA gene rs9288953 C allele was significantly increased in PTB patients with drug resistance. Moreover, the methylation levels of B7-H4 and BTLA genes in PTB patients were greater than that in controls, and rs10754339 variant in B7-H4 gene could affect its methylation level in PTB patients. Conclusion: B7-H4, BTLA genes polymorphism might not affect PTB susceptibility, while the abnormal methylation levels of B7-H4, BTLA genes were associated with the genetic background of PTB.

Expression of B7-H4 in endometrial cancer and its impact on patients' prognosis.

OBJECTIVES: The aim of the study was to evaluate the B7-H4 expression in endometrial cancer cells and to investigate its relationship with patient prognosis and clinicopathological features of the disease. MATERIAL AND METHODS: We performed a single-center, retrospective cohort study that included endometrial cancer patients treated between 2012 and 2019. B7-H4 expression in specimens obtained from 63 patients was examined by immunohistochemical staining. The evaluation of B7H4 immunoreactivity was assessed using Immunoreactivity Scoring (IRS) system. RESULTS: B7-H4 reactivity was observed in all, except one, endometrial cancer patients (98%). Staining intensity: no reaction in one case, weak in 16 (24%) patients, moderate in 25 (37%), and strong in 22 (35%). Twenty-nine (46%) patients showed B7-H4 immunoreactivity in more than 60% of cells, while, in 18 (29%) cases and 16 (25%) patients, the percentages were 30-60% and < 30% respectively. Median IRS was 2 (range 0-6). We found a significantly worse overall survival (OS) rate for patients with high versus low B7-H4 IRS (p = 0.03), however, in multivariate analysis, the difference in patient survival was close to the significance level (p = 0.052). B7-H4 expression was not related to histopathological type of the tumor, tumor grade, lymph node metastases, or the FIGO stage of the disease. CONCLUSIONS: Our result suggests that B7-H4 expression might be a useful prognostic factor in endometrial cancer.