Background: Although immune checkpoint inhibitors (ICIs), especially programmed cell death protein 1 (PD-1)/programmed death ligand 1 (PD-L1) axis blockers, exhibit prominent antitumor effects against numerous malignancies, their benefit for patients with prostate cancer (PCa) has been somewhat marginal. This study aimed to assess the feasibility of B7-H3 or HHLA2 as alternative immunotherapeutic targets in PCa.

Methods: Immunohistochemistry was performed to evaluate the expression pattern of PD-L1, B7-H3 and HHLA2 and the infiltration of CD8⁺ and Foxp3⁺ lymphocytes in 239 PCa tissues from two independent cohorts. The correlations between B7-H3 and HHLA2 and clinicopathological features, including the presence of CD8⁺ and Foxp3⁺ tumor-infiltrating lymphocytes (TILs), were explored.

Results: HHLA2 expression was much higher than PD-L1 expression but lower than B7-H3 expression in PCa tissues. High expression of both B7-H3 and HHLA2 was significantly associated with higher Gleason score and tumor stage, lymph node metastasis and dismal overall survival (OS) and cancer-specific survival (CSS). Moreover, a high B7 score, defined as high B7-H3 expression and/or high HHLA2 expression, was an independent prognostic predictor for PCa. Of note, a high B7 score was negatively correlated with CD8⁺ TILs. Importantly, a new immune classification, based on the B7 score and CD8⁺ TILs, successfully stratified OS and CSS in PCa.

Conclusions: Both B7-H3 and HHLA2 have a critical impact on the immunosuppressive microenvironment, and the B7 score could be used as an independent prognostic factor for PCa. The B7 score combined with CD8⁺ TILs could be used as a new immune classification to stratify the risk of death, especially cancer-related death, for patients with PCa. These findings may provide insights that could improve response to immune-related comprehensive therapy for PCa in the future.

Keywords: costimulatory and inhibitory T-cell receptors; prostatic neoplasms; tumor biomarkers; tumor microenvironment.

Background and objective: Gastric adenocarcinoma (GAC) is one of the most common malignancies. Increasing data have indicated a correlation between soluble B7-H3 (sB7-H3) levels and tumor malignancies. In this study, we aim to investigate the level of soluble B7-H3 in serum of GAC patients. Further, we analyze the correlation between sB7-H3 level and tissue B7-H3 expression and explore the clinical evaluation value of sB7-H3 associated with pathological characteristics and prognosis of GAC patients.

Methods: One hundred and twenty-eight serum and tissue samples of GAC 20 serum and tissue samples of gastritis patients and 77 serum, 5 tissue samples of healthy controls were collected. The serum levels of sB7-H3 were detected by Enzyme-linked immunosorbent assay (ELISA), while the expression of membrane B7-H3 (mB7-H3) and Ki67 were evaluated by immunohistochemistry. The correlation between sB7-H3 and mB7-H3, sB7-H3 and Ki67, sB7-H3 or mB7-H3 and clinical features were analyzed by Pearson's Chi-square test.

Results: Both serum level of sB7-H3 and tissue B7-H3 of GAC patients were significantly higher than those of gastritis patients and healthy controls. sB7-H3 level was correlated with total B7-H3 expression in tissues (r= 0.2801, P= 0.0014). Notably, the concentration of sB7-H3 was correlated with its expression of membrane form in tumor cells (r= 0.3251, P= 0.002) while not in stromal cells (r= 0.07676, P= 0.3891). Moreover, the levels of sB7-H3 in patients with TNM stage III/IV or with Infiltration depth T3/T4 or with lymph node metastasis were significantly higher than those of patients with TNM stage I/II (P= 0.0020) or with Infiltration depth T1/T2 (P= 0.0169) or with no lymph node metastasis (P= 0.0086). Tumor B7-H3 score, but not stromal B7-H3 score, in patients with TNM stage III/IV or with lymph node metastasis was significantly higher than those with TNM stage I/II (P= 0.0150) or with no lymph node metastasis (P= 0.182).

Conclusions: Soluble B7-H3 level may reflect the tissue B7-H3 expression on tumor cells of GAC tissues. Elevated level of sB7-H3 in serum suggests poor clinical pathological characteristics of GAC patients.

Keywords: Gastric adenocarcinoma; membrane B7-H3; prognosis; soluble B7-H3.

B7-H3 and B7-H4 play an inhibitory role in T-cell function by limiting proliferation and cytokine production. Information about B7-H3 and B7-H4 expression in ductal carcinoma in situ (DCIS) remains uncertain. The objective of this study was to evaluate the expression levels of B7-H3 and B7-H4 in DCIS and their associations with clinicopathologic features and T-cell infiltration. B7-H3 and B7-H4 mRNA and protein expression levels in 8 pairs of DCIS tissues and matched normal adjacent tissues were examined by RNAscope in situ hybridization and immunohistochemistry analysis. Immunohistochemical staining of B7-H3, B7-H4, CD3, and CD8 was performed for 79 DCIS samples using tissue microarray. RNAscope in situ hybridization and immunohistochemistry analysis revealed that expression levels of B7-H3 and B7-H4 in DCIS tissues were higher than those in corresponding normal tissues. B7-H3 and B7-H4 mRNA and protein appeared to be mainly expressed in DCIS carcinoma cells. High B7-H3 and B7-H4 expression was observed in 58 (73.4%) and 62 (78.5%) cases with DCIS, respectively. High B7-H3 expression was significantly associated with high-nuclear grade and presence of comedo-type necrosis (both P<0.05). B7-H3 expression in HR/HER2 subtype was higher than that in HR/HER2 subtype (P<0.05). B7-H3 and B7-H4 expression levels were negatively related to the density of CD3 and CD8 T-cell infiltrates. B7-H3 and B7-H4 may play an important role in immune surveillance mechanisms of DCIS. They might be useful targets to develop immune-based therapy to alter or prevent DCIS progression.

Ductal carcinoma in situ (DCIS) will account for 62,930 cases of breast cancer in 2019. DCIS is a pre-invasive lesion which may not progress to invasive carcinoma, yet surgery remains the mainstay treatment. Molecular imaging of a specific marker for DCIS grade for detection and active surveillance are critically needed to reduce potential overtreatment. First, breast cancer marker B7-H3 (CD276) expression was evaluated by immunohistochemical staining in 123 human specimens including benign epithelium (H-score 10.0 ± 8.2) and low (20.8 ± 17.7), intermediate (87.1 ± 69.5), and high (159.1 ± 87.6) grade DCIS, showing a positive association with DCIS nuclear grade (P < 0.001, AUC 0.96). Next, a murine DCIS model was combined with ultrasound molecular imaging of B7-H3 targeted microbubbles to differentiate normal glands from those harboring DCIS (n = 100, FVB/N-Tg(MMTVPyMT)634Mul, AUC 0.89). Finally, photoacoustic and fluorescence molecular imaging with an anti-B7-H3 antibody-indocyanine green conjugate were utilized for DCIS detection (n = 53). Molecular imaging of B7-H3 expression may allow for active surveillance of DCIS.

Clinical studies with adoptive immunotherapy using allogeneic natural killer (NK) cells showed feasibility, but also limitation regarding the transfused absolute cell numbers. First promising results with peripheral blood mononuclear cells (PBMCs) as feeder cells to improve the final cell number need further optimization and investigation of the unknown controlling mechanism in the cross-talk to NK cells. We investigated the influence of irradiated autologous PBMCs to boost NK cell proliferation in the presence of OKT3 and IL-2. Our findings demonstrate a requirement for receptor-ligand interactions between feeders and NK cells to produce soluble factors that can sustain NK cell proliferation. Thus, both physical contact between feeder and NK cells, and soluble factors produced in consequence, are required to fully enhance NK cell ex vivo proliferation. This occurred with an indispensable role of the cross-talk between T cells, monocytes, and NK cells, while B cells had no further influence in supporting NK cell proliferation under these co-culture conditions. Moreover, gene expression analysis of highly proliferating and non-proliferating NK cells revealed important phenotypic changes on 5-day cultured NK cells. Actively proliferating NK cells have reduced Siglec-7 and -9 expression compared with non-proliferating and resting NK cells (day 0), independently of the presence of feeder cells. Interestingly, proliferating NK cells cultured with feeder cells contained increased frequencies of cells expressing RANKL, B7-H3, and HLA class II molecules, particularly HLA-DR, compared with resting NK cells or expanded with IL-2 only. A subset of HLA-DR expressing NK cells, co-expressing RANKL, and B7-H3 corresponded to the most proliferative population under the established co-culture conditions. Our results highlight the importance of the crosstalk between T cells, monocytes, and NK cells in autologous feeder cell-based ex vivo NK cell expansion protocols, and reveal the appearance of a highly proliferative subpopulation of NK cells (HLA-DR+RANKL+B7-H3+) with promising characteristics to extend the therapeutic potential of NK cells.

Costimulatory molecule B7-H3 is a new member of the B7 immunoregulatory family identified in 2001. Although B7-H3 mRNA is widely detected in a variety of lymphoid and nonlymphoid organs, but the B7-H3 protein is distributed limitedly, generally absent or low expressed in normal tissues. The triggering receptor expressed on myeloid cell (TREM)-like transcript 2 (TLT-2) is a possible receptor for B7-H3, but it is not confirmed. B7-H3 has an important immunologic function having costimulatory or coinhibitory immunoregulatory effects in adaptive immune responses, but its exact mechanism remains contentious. The recent studies reported that aberrant overexpression of B7-H3 was found in a wide range of solid cancer tissues and cells, and associated with more advanced disease and poor prognosis, and directly performed nonimmunological functions in oncogenesis. However, more and more studies demonstrate that B7-H3 also plays an important role in progression of hematologic malignancies. The overexpression of B7-H3 is significantly associated with the malignant degree, relapse, progression and prognosis in haematological malignancies. Thus, B7-H3 represents a novel diagnostic marker and potential therapeutic target for cancers. The immunotherapy targeting to B7-H3 become one of the hotspots of recent researches, and some monoclonal antibodies have already entered into clinical trials. This review summarizes the available data on the relationship between B7-H3 and hematologic malignancies, and further focusing on B7-H3 as a potential therapeutic target in these tumors.

Human retinal pigment epithelial (RPE) cells derived from induced pluripotent stem (iPS) cells have immunosuppressive properties. However, RPE cells are also known as immunogenic cells, and they have major histocompatibility complex expression and produce inflammatory proteins, and thus experience immune rejection after transplantation. In this study, to confirm the immunological properties of IPS-RPE cells, we examined whether human RPE cells derived from iPS cells could suppress or stimulate inflammatory T cells from uveitis patients via costimulatory signals. We established T cells from patients with active uveitis as target cells and used iPS-RPE cells as effector cells. As a result, cultured iPS-RPE cells inhibited cell proliferation and the production of IFN-γ by activated uveitis CD4⁺ T cells, especially Th1-type T cells. In contrast, iPS-RPE cells stimulated T cells of uveitis patients. The iPS-RPE cells constitutively expressed B7-H1/CD274 and B7-DC/CD273, and suppressed the activation of T cells via the PD-1 receptor. iPS-RPE expressed these negative costimulatory molecules, especially when RPE cells were pretreated with recombinant IFN-γ. In addition, iPS-RPE cells also expressed B7-H3/CD276 costimulatory molecules and activated uveitis T cells through the B7-H3-TLT-2 receptor. Thus, cultured iPS-derived retinal cells can suppress or activate inflammatory T cells in vitro through costimulatory interactions.

Keywords: costimulatory molecules; iPS cells; retinal pigment epithelial cells; stimulation; suppression; uveitis.

OBJECTIVE

To reveal the clinical significance of B7-H3 costimulatory molecule in myasthenia gravis (MG) patients by analyzing membranous B7-H3 (mB7-H3) and soluble B7-H3 (sB7-H3) expressions.

METHODS

We collected peripheral blood samples of 35 MG patients and 44 health controls (HC) and detected the expression of mB7-H3 on peripheral blood mononuclear cells (PBMCs) using flow cytometry. ELISA was performed to analyze the levels of sB7-H3 in plasma samples from MG patients and HC.

RESULTS

There was no significant difference in the expressions of mB7-H3 on T lymphocytes, monocytes or B cells between MG patients and HC. However, the level of sB7-H3 from MG patients was (2.166±0.958) ng/mL, significantly lower than that from HC (3.379±0.768) ng/mL. The level of sB7-H3 in general MG (GMG) patients (1.664±0.699) ng/mL was lower than that in ocular MG (OMG) patients (2.396±0.985) ng/mL. In MG patients complicated with abnormal thymus, the level of sB7-H3 was (1.593±0.441) ng/mL, also lower than that in MG patients with normal thymus (2.364±1.014) ng/mL. In addition, a significant negative correlation was found between the levels of sB7-H3 and QMGS in MG patients (r=-0.4189, P=0.012), but sB7-H3 was not associated with mB7-H3 in MG patients.

CONCLUSIONS

In MG patients, down-regulation of sB7-H3 is finely correlated to the severity of the disease. Its different expression levels in various types of MG patients indicate that this costimulatory molecule may be involved in the immunopathogenesis of MG.

Although a number of studies have revealed the important roles of miR-34a in cancer, the regulatory roles of miR-34a in cancer immune response remain largely unknown. Our present study demonstrated a mechanism underlying miR-34a-mediated cancer immune evasion via a SIRT1/NF-κB/B7-H3/TNF-α axis. miR-34a upregulated B7-H3, an important immune checkpoint molecule, through direct inhibition of SIRT1 and consequent acetylation of NF-κB subunit p65 (a-p65), which promoted B7-H3 transcription by direct binding to its promoter. The elevated B7-H3 induced production of pro-inflammatory cytokines including TNF-α. This was further confirmed in the colon of Mir34a-deficient mice, where Sirt1 expression was boosted, and the expressions of a-p65, B7h3, and Tnf were repressed. Consequently, the in vivo inhibitory activity of miR-34a on colorectal cancer (CRC) was eradicated by the reinforced B7-H3 and TNF-α. In conclusion, our study uncovered an etiological mechanism underlying miR-34a-mediated CRC immune evasion through inhibition of SIRT1 and promotion of NF-κB/B7-H3/TNF-α axis.

Keywords: B7-H3; Colorectal cancer; Immune evasion; miR-34a.

Background: B7-H3 is an important immunomodulatory molecule, and clinical studies have confirmed that its expression level is closely correlated with prostate cancer prognosis. However, the mechanism of its biological action is unclear.

Methods: An engineered cell line overexpressing B7-H3 was constructed. Cell apoptosis, growth and proliferation assays in vitro and an animal model in vivo were performed to analyze the role and possible mechanism of B7-H3 in promoting prostate cancer progression.

Results: Compared with the control cell line (Mock-RM-1), the B7-H3-overexpressing prostate cancer cell line (B7-H3-RM-1) showed no significant growth differences in vitro, whereas the in vivo tumorigenesis rate of B7-H3-RM-1 was significantly higher than that of Mock-RM-1. These results suggest that B7-H3indirectly, rather than directly, promotes prostate cancer progression. Further analysis revealed that significantly higher levels of myeloid-derived suppressor cells (MDSCs) accumulated in vivo in B7-H3-RM-1 tumor-bearing mice than in Mock-RM-1 mice. In vitro and in vivo experiments showed that B7-H3-RM-1 cells significantly antagonized MDSC apoptosis. To further confirm the role of MDSCs in B7-H3-mediated prostate cancer progression, model mice were pretreated with cyclophosphamide before inoculation to clear immune cells and achieve myelo suppression. The results showed no significant differences in tumor growth between the B7-H3-RM-1 group and the Mock-RM-1 group.

Conclusions: We found, for the first time, that B7-H3 can antagonize MDSC apoptosis, leading to MDSC accumulation in the tumor microenvironment and thereby promoting prostate cancer progression.

Keywords: B7-H3; MDSC; apoptosis; prostate cancer.

Although programmed cell death protein 1/programmed death-ligand 1 (PD-1/PD-L1) and cytotoxic T lymphocyte antigen-4 (CTLA-4) have been successfully applied in the treatment of tumors, their efficiency is still not high enough. New immune targets need to be identified in order to seek alternative treatment strategies for patients with refractory tumors. Immune targets can be divided into stimulating and inhibiting molecules according to their function after receptor-ligand binding. We herein present a compendious summary of emerging immune targets in gynecologic tumors. These targets included coinhibitory molecules, such as T cell immunoglobulin-3 (TIM-3), T cell immunoglobulin and ITIM domain (TIGIT), lymphocyte activation gene-3 (LAG-3), V-type immunoglobulin domain-containing suppressor of T cell activation (VISTA), and B7-H3 and B7-H4, and co-stimulatory molecules, such as CD27, OX40, 4-1BB, CD40, glucocorticoid-induced tumor necrosis factor receptor (GITR) and inducible co-stimulator (ICOS). In this review, the characteristics and preclinical/clinical progress of gynecological malignancies are briefly discussed. However, the potential mechanisms and interactions of immune targets need to be elucidated in further studies.

Keywords: T cell receptors; antigen presenting cells; gynecologic neoplasms; immunotherapy; molecular targeted therapy.

BACKGROUND

B7-H3, a member of the B7 family of the Ig superfamily of proteins, has been detected in the epididymis, which is a storage organ related to sperm maturation. However, the characteristics of its expression in different regions of the epididymis remain unknown. Our aim was to investigate the expression of B7-H3 in the caput, corpus, and cauda of the epididymis.

METHODS

We extracted epididymis specimens from adult male C57BL/6 mice. The expression of B7-H3 was then measured with immunohistochemistry, enzyme-linked immunosorbent assay (ELISA) and western blotting.

RESULTS

B7-H3 protein was predominantly detected on the membrane and in the cytoplasm of the principal cells in the epididymis. Moreover, the level of B7-H3 in the corpus of the mouse epididymis was significantly higher than that in the caput (p < 0.05) or the cauda of the epididymis (P < 0.05). However, there was no remarkable difference in the level of B7-H3 between the caput and the cauda (p>> 0.05).

CONCLUSIONS

The caput, corpus, and cauda of the mouse epididymis all expressed B7-H3 protein. However, the levels of B7-H3 were different in the three regions of the epididymis.

The aim of this study was to investigate the role of B7-H3 in prognosis of congenital heart disease (CHD) children patients. A total of 65 CHD patients within age 3-12 years who went to our hospital were included during August 2011 to December 2012. Demographic data including age, sex, weight, clinical basic information such as New York Heart Association (NYHA) class, pathological type were collected. Blood samples were collected and serum levels of B7-H3, C-reactive protein (CRP), N-Terminal Pro-Brain Natriuretic Peptide (NT-pro-BNP), and High-sensitivity Troponin T (hsTnT) were determined by enzyme-linked immunosorbent assay (ELISA). Characteristics including age, gender, weight, pathological type, NYHA class, and serum levels of hsTnT and CRP showed no significant difference between deceased and survival patients. However, serum levels of B7-H3 and NT-pro-BNP were significantly higher in deceased patients compared survival patients. Patients with high expressed B7-H3 had higher risks for total major cardiovascular events (MACE) occurrence compared with the lower group. Among the MACE events, significant difference was observed in rates of death, new onset of arrhythmias, and surgical, but not in NYHA class worsening and percutaneous intervention. Patients with higher levels if B7-H3 had significantly higher risk for mortality in the 5-year follow-up compared with the lower group, logic analysis was also conducted and results showed that B7-H3 might be an independent risk factor for 5-year mortality for CHD patients. B7-H3 was up-regulated in dead CHD patients, and serum levels of B7-H3 were related to long-term MACE and 5-year mortality of CHD patients.

Head and neck squamous cell carcinoma (HNSCC) has been found to be a complex group of malignancies characterized by their profound immunosuppression and high aggressiveness. In most cases of advanced HNSCC, treatment fails to obtain total cancer cure. Efforts are needed to develop new therapeutic approaches to improve HNSCC outcomes. In this light, T-cells "immune checkpoint" has attracted much attention in cancer immunotherapy. It has been broadly accepted that inhibitory T-cell immune checkpoints contribute to tumor immune escape through negative immune regulatory signals (cytotoxic T-lymphocyte-associated antigen 4 [CTLA-4], programmed cell death 1 [PD-1], B7-H3, and B7-H4, etc). Current data suggest that PD-1 and CTLA-4 receptors can inhibit T-cell receptors and T-cell proliferation. Blockade of PD-1/PD-L1 and/or CTLA-4/CD28 pathways has shown promising tumor outcomes in clinical trials for advanced solid tumors like melanoma, renal cell cancer, and non-small cell lung cancer. The present review attempts to explore what is known about PD-1/PD-L1 and CTLA-4/CD28 pathways with a focus on HNSCC. We further discuss how these pathways can be manipulated with therapeutic intent.

Cervical cancer is a deadly disease. Some microRNAs are involved in tumor invasion and metastasis. Decreased expression of microRNA-199a has been correlated with tumorigenesis. In our study, the quantitative real-time polymerase chain reaction results indicated that microRNA-199a was expressed at lower levels in cervical cancer tissues, and the expression level of B7-H3 was significantly increased compared with that in the adjacent normal tissues, and the expression levels of B7-H3 and microRNA-199a in cervical cancer tissues and in adjacent normal tissues were inversely correlated. We also found that the expression of microRNA-199a was downregulated in cervical cancer cell lines when compared to immortalized cells. In this study, B7-H3 was identified as a novel target of microRNA-199a in cervical cancer. TargetScan (http://www.targetscan.org/) bioinformatics analysis was used to predict that the 3'-untranslated region of B7-H3 is a direct target of microRNA-199a. The result was also verified by the luciferase reporter assay. MicroRNA-199a could directly target the 3'-untranslated region of B7-H3, but the specific signaling pathways that were involved in regulating B7-H3 expression remained unclear. To clarify whether the suppressive effect of microRNA-199a was mediated through B7-H3, a series of experiments were performed. We found that the overexpression of microRNA-199a inhibited cell proliferation, migration, and invasion via direct binding to B7-H3. Epithelial-mesenchymal transition is a major factor involved in cervical cancer metastasis. Quantitative real-time polymerase chain reaction and western blot results indicated that microRNA-199a inhibits tumor progression in cervical cancer by targeting B7-H3. The microRNAs regulatory network is quite complex. We further examined the effect of microRNA-199a on the AKT/mTOR signaling pathway. We explored the regulatory role of microRNA-199a and first demonstrated that highly expressed microRNA-199a inhibits tumor growth and activates the AKT/mTOR signaling pathway by targeting B7-H3 in vivo and in vitro. Our findings not only provide a better understanding of the pathogenesis of cervical cancer but also provide novel findings and theoretical support for potential targeted therapeutic tools for cervical cancer.

Keywords: B7-H3; MiR-199a; cervical cancer; migration; proliferation.

BACKGROUND

T cells have been shown to play a role in the etiopathogenesis of periodontal disease. B7-H3, a costimulatory molecule, is found to be associated with regulation of T cell function in some tumoral tissues, as well as autoimmune and inflammatory diseases.

OBJECTIVE

The aim of this study was to investigate the expression of B7-H3 molecule in healthy and diseased gingival tissue samples.

METHODS

Gingival samples were taken from 2 groups (A and B) representing periodontal health and periodontal disease, respectively. These were paraffinized and processed to carry out immunostaining to identify B7-H3 expression. The slides were then examined under light microscope to assess the positive staining in epithelium and connective tissue. The intensity of positive staining in epithelium and the number of positive cells in the connective tissue were evaluated. Statistical analysis was done using kappa analysis and independent t-test.

RESULTS

Kappa analysis revealed good inter-examiner agreement for both the groups (group A: 0.718; group B: 0.797). Intensity of staining in the epithelium ranged from intense to moderate for both the groups. In the connective tissue, there was a statistically insignificant decrease (p value= 0.415) in the number of positive cells from group A (mean labeling index: 50.28±26.09) to group B (mean labeling index= 41.37±25.29).

CONCLUSIONS

B7-H3 molecule has been found to be expressed in gingival tissue samples; however, it showed a statistically insignificant decrease in periodontal disease group compared to healthy group.

The management of multiple primary cancers, an event not so infrequent in oncology practice, is a critical issue due to the lack of literature. In this study, we reported the case of a patient with non-small cell metastatic lung cancer (NSCLC) and pancreatic ductal adenocarcinoma (PDAC) who received gefitinib in combination with gemcitabine plus nab-paclitaxel and with mFOLFOX6 in first and second line, respectively. It achieved a progression-free survival and a28-months overall survival (OS) for NSCLC and PFS-1 and OS of 20 and 13 months, respectively for PDAC. Moreover, the combination of gefitinib and chemotherapy treatmentsshowed a good safety profile. Given the insignificant frequency of this case, we performed a molecular characterization of both neoplasms with the aim to investigate the existence of particular activated pathways and/or similar immunological mutations. It is interesting to note that two neoplasms shared a common mutation ofthe B7-H3 gene, with the consecutive impairment of its expressed protein. In both PDAC and NSCLC, the expression of this protein was associated with a worse survival rate. Since B7-H3 is an anti-apoptotic protein, the reduction of its expression or function should justify a pro-apoptotic activity with a leading justification of the long survival of the patient considered in this report.

Objective To investigate the expression and biological significance of costimulatory molecule B7-H6, a member of B7 family, in glioma stem like cells (GSLCs). Methods In virtue of the ability of forming neurospheres in vitro , GSLCs were isolated from U87 cells by cell sub-cloning. Real-time quantitative PCR and flow cytometry were performed to detect the expressions of stem cell related markers (c-myc, Sox2, CD133, nestin, and CXCR4), as well as the expressions of B7 family molecules. The different doses of adriamycin, carboplatin, cisplatin, were used to treat GSLCs for testing their chemotherapy-resistance. After the expression of B7-H6 in GSLCs was knockdown by siRNA, CCK-8 method was used to detect cell proliferation. Results GSLCs were successfully isolated from U87 cells, which formed neurospheres in vitro . The expressions of multiple stem cell markers were up-regulated and the GSLCs showed enhanced chemo therapy-resistance. B7 family members, B7-H1, B7-H3, B7-H4 and B7-H6 were expressed in GSLCs. Compared with primary U87 cells, GSLCs presented with a remarkably increased expression of B7-H6 on cell membrane. When B7-H6 was silenced by siRNA, cell proliferation was inhibited along with the decrease of c-myc expression. Conclusion The expression of B7-H6 is up-regulated in U87-derived GSLCs, which is associated with the biological characteristics of GSLCs.

Surgical stress initiates a series of host hormone, metabolism and immune responses, which predominantly affect the homeostatic mechanism of patients with major surgery. B7-H3 is a co-stimulatory molecule and has been shown to participate in both adaptive and innate immune responses. In this study we evaluated the clinical significance of plasma B7-H3 levels in pediatric patients with different types of operation and degrees of surgical stress.

A total of 48 children received pediatric general and cardiac surgery were recruited into this study. Based on the surgical stress scoring, children were divided into moderate stress (n = 14) and severe stress (n = 34) groups. Plasma B7-H3 levels were assessed at selected time points: before surgery, immediately after surgery, at day 1, day 3, and day 7 after surgery. Correlations between plasma B7-H3 levels and surgical stress scores were also examined.

Plasma B7-H3 levels were significantly decreased in all 48 pediatric patients after surgery compared to the B7-H3 level before surgery (p < 0.01). Children with general surgery showed significant decreases in plasma B7-H3 immediately after surgery, and at day 3 and day 7 after surgery (p < 0.05, p < 0.01), whereas children with cardiac surgery showed reduced plasma B7-H3 immediately after surgery and at day 3 after surgery (p < 0.05). Plasma B7-H3 in cardiac surgery group was dropped much lower than that in general surgery group at day 1 (p < 0.05) and day 3 (p < 0.01) after surgery. Significantly reduced plasma B7-H3 was observed in the severe stress group, but not in the moderate stress group, immediately after surgery and at day 3 after surgery (p < 0.05), and severe stress group had significantly lower plasma B7-H3 levels than moderate stress group at day 1, day 3, and day 7 after surgery (p < 0.05). Furthermore, plasma B7-H3 levels at day 1 (p = 0.01) and day 3 (p = 0.025) after surgery correlated negatively with surgical stress scores.

Plasma B7-H3 levels were decreased significantly in children subjected to pediatric general and cardiac surgery, which is closely associated with the severity of surgical stress. The negative correlation of plasma B7-H3 levels at day 1 and day 3 after surgery with surgical stress scoring implicates that the plasma B7-H3 level might be a useful biomarker for monitoring stress intensity during pediatric surgery.

Background: CD276 is an immune checkpoint molecule. Elevated CD276 expression by urothelial carcinoma is associated with poor prognosis, but little is known about its expression across different tumor stages. We therefore investigated CD276 expression in bladder cancer (BC) cells and in tissue samples of BC stages from pT2 to pT4.

Methods: CD276 expression was explored in 4 urothelial cancer cell lines and 4 primary normal urothelial cell populations by quantitative RT-PCR, Western blot and flow cytometry. CD276 was investigated in bladder tumors from 98 patients by immunohistochemistry using a score (0-300) incorporating both, staining intensity and area of CD276 staining. Normal appearing urothelium in the bladder of the same patients served as controls.

Results: The urothelial carcinoma cell lines expressed significantly higher levels of CD276 on transcript (p < 0.006), total protein levels (p < 0.005), and on the cell surface (p < 0.02) when compared to normal urothelial cells. In pT2-T4 tumor tissue samples, CD276 was overexpressed (median score 185) when compared to corresponding healthy tissues from the same patients (median score 50; p < 0.001). No significant differences in CD276 expression were recorded in late, locally advanced ≥ pT3a tumors (median score 185) versus organ-confined < pT3a tumors (median score 190), but it was significantly lower in the normal urothelial tissue associated with ≥ pT3a tumors (median score 40) versus < pT3a tumors (median score 80; p < 0.05).

Conclusion: CD276 expression is significantly elevated in urothelial carcinoma cells in all stages but varies between individuals considerably. Reduced CD276 expression in normal urothelial cells may imply that these cells would be protected from CD276-mediated immuno therapies.

Keywords: B7-H3; Bladder tumor stages; CD276; Immune check-point protein; Urothelial carcinoma.

OBJECTIVE

To investigate the role of B7-H3 in the immune reaction of corneal transplantation in mice

METHODS

Experimental study. Thirty Corneas of C57BL/6 mice were orthotopically transplanted into the eyes of BALB/c mice, and graft survival was assessed on the basis of Sonoda's standard. When the RI grade was ≥ 2, rejection was acknowledged and brought into the rejected group(R), and the others into the accepted group (A); 8 BALB/c Corneas into their own eyes belonged to isografts (I) ; In addition, 8 normal BALB/c mice were the control group (C) . At last, three eyes in each group (C, I, A, R groups) were used for HE staining and IHC of B7-H3, and there were five eyes in each group for qPCR to detect B7-H3 mRNA expression. Repeated-measures analysis of variance (factorial analysis) followed by LSD test were used for post hoc analysis for expression differences of B7-H3 mRNA between groups.

RESULTS

There were 9 accepted grafts and 21 rejected grafts in 30 mice, and transplantation survival rate was 30% in the allograft group, while all grafts were transparent, and transplantation survival rate was 100% in the isografts. IHC results showed that B7-H3 was expressed on the corneal epithelium, endothelium and iris-ciliary body of both normal corneas and Isografts; B7-H3 expression increased in the accepted group and decreased in the rejected group . The results of qPCR conformed to the IHC; Repeated-measures analysis of variance (factorial analysis) followed by LSD test were used for post hoc analysis for differences between groups (F = 429.546) . there was a low B7-H3 mRNA expression in the R group (3.89 ± 0.037) and high expression in the A group (5.04 ± 0.058); and C (4.30 ± 0.023) ,I (4.33 ± 0.031) groups had no significant difference (P = 0.387) ;But there was a significant difference between group R and C (P = 0.003)or group A and C(P = 0.001).

CONCLUSIONS

All above show that B7-H3 may play an important role in the maintenance of ocular immune privilege.

[This corrects the article DOI: 10.7150/jca.37255.].