Co-inhibitory Molecule B7 Superfamily Member 1 Expressed by Tumor-Infiltrating Myeloid Cells Induces Dysfunction of Anti-tumor CD8+ T Cells.

The molecular mechanisms whereby CD8+ T cells become "exhausted" in the tumor microenvironment remain unclear. Programmed death ligand-1 (PD-L1) is upregulated on tumor cells and PD-1-PD-L1 blockade has significant efficacy in human tumors; however, most patients do not respond, suggesting additional mechanisms underlying T cell exhaustion. B7 superfamily member 1 (B7S1), also called B7-H4, B7x, or VTCN1, negatively regulates T cell activation. Here we show increased B7S1 expression on myeloid cells from human hepatocellular carcinoma correlated with CD8+ T cell dysfunction. B7S1 inhibition suppressed development of murine tumors. Putative B7S1 receptor was co-expressed with PD-1 but not T cell immunoglobulin and mucin-domain containing-3 (Tim-3) at an activated state of early tumor-infiltrating CD8+ T cells, and B7S1 promoted T cell exhaustion, possibly through Eomes overexpression. Combinatorial blockade of B7S1 and PD-1 synergistically enhanced anti-tumor immune responses. Collectively, B7S1 initiates dysfunction of tumor-infiltrating CD8+ T cells and may be targeted for cancer 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.

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.

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.

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.

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.

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.

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.

The third group of the B7-CD28 immune checkpoint family: HHLA2, TMIGD2, B7x, and B7-H3.

The B7-CD28 family of ligands and receptors play important roles in T-cell co-stimulation and co-inhibition. Phylogenetically they can be divided into three groups. The recent discovery of the new molecules (B7-H3 [CD276], B7x [B7-H4/B7S1], and HHLA2 [B7H7/B7-H5]/TMIGD2 [IGPR-1/CD28H]) of the group III has expanded therapeutic possibilities for the treatment of human diseases. In this review, we describe the discovery, structure, and function of B7-H3, B7x, HHLA2, and TMIGD2 in immune regulation. We also discuss their roles in important pathological states such as cancers, autoimmune diseases, transplantation, and infection. Various immunotherapeutical approaches are emerging including antagonistic monoclonal antibodies and agonistic fusion proteins to inhibit or potentiate these molecules and pathways in cancers and autoimmune diseases.

B7H4 expression in tumor cells impairs CD8 T cell responses and tumor immunity.

B7 homolog 4 (B7H4) is considered a negative regulator of immune responses, but the immunoregulatory role of B7H4 in the tumor microenvironment is not clear. Here, we assessed B7H4 expression cell types in human breast cancer tissues and addressed its potential mechanisms in the CD8 T cell immune response. The results from flow cytometry and immunohistochemistry demonstrated that B7H4 was highly expressed in 26 out of 30 (86.7%) breast invasive ductal carcinomas, and B7H4 surface expression on tumor cells was inversely correlated with CD8 T lymphocytes infiltration (p < 0.0001). In vivo, B7H4-overexpressing tumor cells showed enhanced tumor growth in immunocompetent mice with impaired CD8 T cell infiltration of the tumor. Further investigation showed that activation and expansion of CD8 T cells within the lymph nodes were suppressed in B7H4-overexpessing tumor-bearing mice. An in vitro killing assay showed that the cytotoxicity of CD8 T cells was inhibited in B7H4-overexpressing tumor cells. These findings suggest that B7H4 in tumor cells is a negative regulator of CD8 T cell activation, expansion and cytotoxicity, indicating that tumor cell-associated B7H4 might be a target for T cell-based cancer immunotherapy.

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.

B7-H4, a promising target for immunotherapy.

The coinhibitory molecule B7-H4, an important member of the B7 family, is abnormally expressed in tumors, inflammation and autoimmune diseases. B7-H4 negatively regulates T cell immune response and promotes immune escape by inhibiting the proliferation, cytokine secretion, and cell cycle of T cells. Moreover, B7-H4 plays an extremely important role in tumorigenesis and tumor development including cell proliferation, invasion, metastasis, anti-apoptosis, etc. In addition, B7-H4 has the other biological functions, such as protection against type 1 diabetes (T1D) and islet cell transplantation. Therefore, B7-H4 has been identified as a novel marker or a therapeutic target for the treatment of tumors, inflammation, autoimmune diseases, and organ transplantation. Here, we summarized the expression profiles, physiological and pathological functions, and regulatory mechanisms of B7-H4, the signaling pathways involved, as well as B7-H4-based immunotherapy.

B7-H4 is a potential prognostic biomarker of prostate cancer.

B7-H4 is a member of B7 family which regulates immune responses by delivering costimulatory signals. However, it negatively regulates T cell-mediated immunity and may play an important role in tumor immune evasion. Although several studies have been reported that expression of B7-H4 is elevated in the several types of human cancer with a poor clinical outcome, its clinical significance in the prostate cancer (PCa) has not been well studied. In this study, we investigated the clinical significance of B7-H4 in human PCa and determined if B7-H4 expression is associated with the cancer cell stemness in PCa. Our studies show that expression of B7-H4 is correlated with the pathologic tumor (pT) stage and the clinical stage of PCa. The Kaplan-Meier survival analysis revealed that PCa patients with high expression of B7-H4 exhibits a shorter overall survival (OS) rate. Univariate and multivariate Cox regression analysis indicated that B7-H4 is an independent poor prognostic factor of PCa. In addition, the expression of B7-H4 is correlated with the cancer cell stemness associated genes expression in PCa. Further, our studies show that B7-H4 regulates cancer cell stemness associated genes expression and effects on the cell cycle and PI3K/Akt signaling related genes expression in PCa. These results indicate that B7-H4 expression is associated with cancer cell stemness, and B7-H4 is a potential prognostic biomarker and a therapeutic target of PCa.

B7-H3 and B7-H4 Expression in Breast Cancer and Their Association with Clinicopathological Variables and T Cell Infiltration.

OBJECTIVES: B7-H3 and B7-H4 proteins are expressed in breast cancer tissues, but their relationships with respect to tumor immune surveillance and outcomes in breast cancer are not conclusive. METHODS: We first examined B7-H3 and B7-H4 mRNA expression in the Genotype-Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) datasets. Next, mRNA and protein expression were assessed by RNAscope in situ hybridization (ISH) and immunohistochemistry in 10 pairs of breast cancer and matched normal tissues. Immunohistochemical staining of B7-H3, B7-H4, CD3, and CD8 was performed in tissue microarray slides containing 198 breast cancer samples. Association of B7-H3 and B7-H4 expression with survival was verified using the publicly accessible BreastMark tool. RESULTS: B7-H3 and B7-H4 mRNA expression were significantly higher in breast cancer samples in the TCGA dataset than in normal breast tissues in the GTEx dataset. RNAscope ISH and immunohistochemistry showed that B7-H3 and B7-H4 mRNA and protein appeared to be mainly expressed in cancer cells. Expression of B7-H3 and B7-H4 tended to be associated with low-density scores of stromal tumor-infiltrating lymphocytes (TILs) as well as molecular subtypes. Expressions of B7-H3 and B7-H4 were negatively correlated with stromal CD3+ and CD8+ T cell infiltration density. B7-H3 and B7-H4 expression was not associated with survival, which was verified by BreastMark analysis. CONCLUSION: Expression levels of B7-H3 and B7-H4 were independent of clinical outcomes of breast cancer. There was an inverse relationship between the expression of B7-H3 and B7-H4 in breast cancer and the density of stromal TILs and CD8+ T lymphocytes. This inverse relationship may represent a promising target in the field of breast cancer immunotherapy.

Negative roles of B7-H3 and B7-H4 in the microenvironment of cervical cancer.

Although persistent human papilloma virus (HPV) infection exerts a crucial influence on cervical carcinogenesis, other factors are also involved in its development, such as intraepithelial lesions and cervical cancer. B7-H3 and B7-H4, which have been reported to be co-regulatory ligands in the B7 family, had been found to be overexpressed in cervical cancer and correlated with adverse clinicopathological features and poor prognosis in our previous studies. In this study, we sought to explore the effects of B7-H3 and B7-H4 on the cervical microenvironment. Among several immune cytokines, interleukin-10 (IL-10) and transforming growth factor (TGF) ß1 stand out as important immunosuppressive factors. Our studies found that IL-10 expression increased with pathological change levels and significantly correlated with cervical cancer differentiation (P < 0.05). TGF-ß1 correlated with lymph node metastasis (LNM) (P < 0.01). Expression of B7-H3 and B7-H4 positively correlated with the expression of IL-10 and TGF-ß1. After co-culture, we found that overexpression of B7-H3 and B7-H4 in cervical cancer cell lines resulted in activation of the cell cycle and decreased apoptosis of U-937 cells. In addition, the contents of IL-10 and TGF-ß1, as well as their protein expression levels, increased in co-culture supernatants in U-937 cells, suggesting regulation by the p-JAK2/STAT3 pathway. The in vivo results demonstrated that with the increasing expression of B7-H3/B7-H4, the expression of IL-10 and TGF-ß1 also increased significantly. Overall, the expression of B7-H3 and B7-H4 favored an immunosuppressive microenvironment by promoting the production of IL-10 and TGF-ß1, thereby resulting in progression of cervical carcinogenesis.

Molecular subgroups and B7-H4 expression levels predict responses to dendritic cell vaccines in glioblastoma: an exploratory randomized phase II clinical trial.

Dendritic cell (DC)-based vaccination is a promising approach for active-specific immunotherapy, but is currently of limited efficacy. The safety and effectiveness of a DC vaccine (DCV) loaded with glioblastoma stem cell-like (GSC) antigens was assessed in glioblastoma multiforme (GBM) patients. In this double-blind, placebo-controlled phase II clinical trial, 43 GBM patients were randomized after surgery at a 1:1 ratio to receive either DCV (n = 22) or normal saline placebo (n = 21). Overall survival (OS) and progression-free survival (PFS) were analysed. Participants were stratified into different molecular subgroups based on the mutation (MT) status of isocitrate dehydrogenase (IDH1/2) and telomerase reverse transcriptase (TERT). Plasma cytokine levels, tumor-infiltrating lymphocyte numbers and immune co-inhibitory molecules PD-L1 and B7-H4 were also assessed. Multivariate Cox regression analysis revealed that DCV treatment significantly prolonged OS (p = 0.02) after adjusting for IDH1 and TERT promoter MT and B7-H4 expression, primary vs recurrent GBM. Among IDH1wild type (WT) TERTMT patients, DCV treatment significantly prolonged OS (p < 0.01) and PFS (p = 0.03) and increased plasma levels of cytokines CCL22 and IFN-γ compared with placebo. Patients with low B7-H4 expression showed significantly prolonged OS (p = 0.02) after DCV treatment. Therefore, IDH1WTTERTMT and low B7-H4 expression identified subgroups of GBM patients more responsive to GSC DCV-based specific active-immunotherapy.

B7-H3 and B7-H4 expression in phyllodes tumors of the breast detected by RNA in situ hybridization and immunohistochemistry: Association with clinicopathological features and T-cell infiltration.

Phyllodes tumors are rare biphasic breast tumors with the potential for both local recurrence and distant metastasis. The aberrant expression of B7-H3 and B7-H4 B7 molecules could be potential targets for future development of immunotherapeutic approaches. This work was undertaken to evaluate the expression of B7-H3 and B7-H4 in phyllodes tumors and assess the association with the grade and clinical behavior of phyllodes tumors. In addition, the roles of B7-H3 and B7-H4 in the regulation of tumor immune surveillance were evaluated by assessing the relationship between B7-H3/B7-H4 expression and T-cell infiltration. The messenger RNA and protein expression of B7-H3/B7-H4 were determined by RNAscope in situ hybridization and immunohistochemistry, respectively, in 101 phyllodes tumors (60 benign, 26 borderline, and 15 malignant) using a tissue microarray. Immunohistochemistry for CD3 and CD8 was also performed. B7-H3 messenger RNA and protein appeared to be concentrated mainly in the stromal compartment of phyllodes tumors. However, B7-H4 messenger RNA and protein were undetectable in the stromal compartment of phyllodes tumors. Stromal B7-H3 messenger RNA and protein expression were noted in 10 (16.7%) and 31 (51.7%) of 60 benign phyllodes tumors, 12 (46.1%) and 20 (76.9%) of 26 borderline phyllodes tumors, and 10 (66.7%) and 13 (86.7%) of 15 malignant phyllodes tumors, respectively. Stromal B7-H3 messenger RNA and protein expression increased as phyllodes tumors progressed from benign to borderline and finally to the malignant grade (Pearson's R = 0.411, p < 0.001 and Pearson's R = 0.293, p = 0.003, respectively). The recurrence rate was higher in the stromal B7-H3 messenger RNA or protein-positive group than in the negative group, but this difference was not significant. Stromal B7-H3 protein expression inversely correlated with the densities of CD3+ and CD8+ T-cell infiltrates ( p = 0.001 and p = 0.027, respectively). These results suggest that B7-H3 is involved in the progression of phyllodes tumors and may contribute to their immune surveillance.