BACKGROUND

Chemoresistance is a major obstacle to successful chemotherapy for human non-small cell lung cancer (NSCLC). Astragaloside IV, the component of Astragalus membranaceus, has been reported to exhibit anti-inflammation, anti-cancer and immunoregulatory properties. In the present study, we investigated the role of astragaloside IV in the chemoresistance to cisplatin in NSCLC cells.

METHODS

We established astragaloside IV-suppressed NSCLC cell lines including A549, HCC827, and NCI-H1299 and evaluated their sensitivity to cisplatin in vitro. In addition, we examined the mRNA and protein levels of B7-H3 in response to cisplatin-based chemotherapy.

RESULTS

We showed that high doses of astragaloside IV (10, 20, 40 ng/ml) inhibited NSCLC cell growth, whereas low concentrations of astragaloside IV (1, 2.5, 5 ng/ml) had no obvious cytotoxicity on cell viability. Moreover, combined treatment with astragaloside IV significantly increased chemosensitivity to cisplatin in NSCLC cells. On the molecular level, astragaloside IV co-treatment significantly inhibited the mRNA and protein levels of B7-H3 in the presence of cisplatin. In addition, ectopic expression of B7-H3 diminished the sensitization role of astragaloside IV in cellular responses to cisplatin in NSCLC cells.

CONCLUSIONS

These results demonstrate that astragaloside IV enhances chemosensitivity to cisplatin via inhibition of B7-H3 and that treatment with astragaloside IV and inhibition of B7-H3 serve as potential therapeutic approach for lung cancer patients.

Co-inhibitory signaling from B and T lymphocyte attenuator (BTLA) can suppress lymphocyte activation and maintain peripheral tolerance. However, the expression and anatomical distribution of BTLA and its ligand, herpesvirus entry mediator (HVEM), in rheumatoid arthritis (RA) synovium have not been reported. In this study, we analyzed the expression of HVEM and BTLA in RA synovium by immunohistochemistry, and our results showed that both factors were observed in all four cases of RA samples. At the cellular level, both HVEM and BTLA were found on the cell membrane and in the cytoplasm. Fluorescence dual staining demonstrated that HVEM was chiefly on CD3(+) T cells, CD68(+) macrophages, and to a lesser extent was found on CD31(+) endothelial cells. Similarly, the expression of BTLA was observed on infiltrated CD3(+) T cells and CD68(+) macrophages. The co-expression of HVEM and BTLA with some members of the B7 family in these sections was also analyzed, and the results showed that HVEM antigen was also found on B7-H3(+) capillaries, while it was absent on B7-H1(+), B7-DC(+), B7-H4(+), and Z39Ig(+) cells. Interestingly, BTLA was observed on B7-H1(+), B7-H4(+), and HVEM(+) cells in the synovium. The characteristic expression and distribution of BTLA/HVEM in the synovium indicated that their signaling probably affects the pathogenesis of RA, and a clear understanding of their functional roles may further elucidate the pathogenesis of this disease.

Although PD-L1/PD-1 blockade therapy has been approved to treat many types of cancers, the majority of patients with solid tumors do not respond well, but the underlying reason remains unclear. Here, we studied ovarian cancer (OvCa), a tumor type generally resistant to current immunotherapies, to investigate PD-1-independent immunosuppression. We found that PD-L1 was not highly expressed in the tumor microenvironment (TME) of human OvCa. Instead, B7-H3, another checkpoint molecule, was highly expressed by both tumor cells and tumor-infiltrating antigen-presenting cells (APCs), which correlated with T-cell exhaustion in patients. Using ID8 OvCa mouse models, we found that B7-H3 expressed on tumor cells, but not host cells, had a dominant role in suppressing antitumor immunity. Therapeutically, B7-H3 blockade, but not PD-1 blockade, prolonged the survival of ID8 tumor-bearing mice. Collectively, our results demonstrate that tumor-expressed B7-H3 inhibits the function of CD8⁺ T cells and suggest that B7-H3 may be a target in patients who are not responsive to PD-L1/PD-1 inhibition, particularly OvCa patients.

Previous studies showed that B7-H3 (CD276), a cytokine involved in the activation of T lymphocytes, regulates murine bone formation. However, the role of B7-H3 in bone formation is barely understood. Herewith, we report, that stimulation of B7-H3 promotes the differentiation of human marrow stromal cells (hMSCs) to osteoblasts. With 4H7, a new monoclonal antibody against human B7-H3, we have identified B7-H3 is located on the surface of human marrow stromal cells. Evermore, we have found that increase of B7-H3 levels are correlated with the differentiation course of hMSCs. Stimulation of B7-H3 with 4H7 antibody considerably increases the numbers of osteoblasts generated from the hMSCs in the presence of inducing medium containing dexamethasone, sodium β-glycerophosphate and l-ascorbic acid. 4H7 treatments significantly increase osteoblast markers including alkaline phosphatase (ALP), and osteocalcin (OC) after day 7 and day 14 of the inducing hMSCs differentiation. The numbers of mineralized nodules of osteoblasts have been remarkly increased after 21 days of induced differentiation of hMSCs. However, stimulation effects of 4H7 antibody on membrane B7-H3 has been eliminated by addition of B7-H3Fc fusion protein. These results indicate 4H7 antibody specifically stimulates the membrane B7-H3 and directs the differentiation of hMSCs. Furthermore, our study also shows that stimulation of B7-H3 increases the expression of osteoprotein (OPG), and decreases the expression of its cognate ligand, the receptor activator of nuclear factor kappaB ligand (RANKL).

B7-H3, a member of the B7 family of molecules, is expressed in certain types of human cancer and is important in tumor development and progression. Although several studies have reported that the expression of B7-H3 is correlated with poor outcomes in patients with cancer, its exact role in cancer remains unknown. In the present study, the expression levels of B7-H3 in the pathological specimens of 105 patients treated for non-small cell lung cancer (NSCLC) were examined by immunohistochemistry. A high expression level of B7-H3 was observed in 46.9% of the 105 NSCLC tissue specimens. These patients demonstrated a more advanced tumor grade and a shorter survival time. In addition, we also examined the levels of tumor-associated macrophages (TAMs) in NSCLC tissues and observed that the levels were positively correlated with the expression of B7-H3, and that higher levels of macrophages were associated with lower levels of infiltrating T cells and a shorter survival time. These results demonstrated that TAMs are important in the evasion of tumor immune surveillance in NSCLC. Furthermore, through knockdown of B7-H3 by RNA interference, we observed that soluble B7-H3 was capable of inducing macrophages to express higher levels of macrophage mannose receptor (MMR) and lower levels of human leukocyte antigen (HLA)-DR, as well as higher levels of interleukin-10 (IL-10) and lower levels of IL-1β in vitro. These observations are characteristic of an anti-inflammatory/reparatory (alternative/M2) phenotype. Therefore, our data suggests that B7-H3 proteins are involved in the progression of NSCLC by inducing the development of monocytes into anti-inflammatory cells.

The costimulatory molecules B7-H3 and B7-H4 are overexpressed in a variety of human tumors and have been hypothesized as possible biomarkers and immunotherapeutic targets. Despite this potential, the predominating uncertainty about their functional implication in tumor-host interaction hampers their evaluation as a target for cancer therapy. By means of a highly physiologic, spontaneous tumor model in mice, we establish a causal link between B7-H3 and host tumor control and found B7-H4 to be redundant.

B7-H3 is a transmembrane protein and a member of the B7 family of immune regulatory ligands. It exerts both inhibitory and stimulatory effects on the activation of T cells. We investigated the expression of B7-H3 in invasive squamous cell carcinoma (ISCC) of the uterine cervix by immunohistochemistry, and aimed to determine whether expression of this factor is involved in the progression of the morphologic spectrum from normal cervical epithelia to cervical intraepithelial neoplasia and cervical ISCC. In addition, we sought to examine the relation of B7-H3 to the abundance of tumor-infiltrating and tumor-associated CD8(+) lymphocytes and to the evidence of phosphohistone H3, which is a core histone protein detected during mitosis. B7-H3 immunostaining was scored with regard to quantity and intensity of positively stained cells, and was noted in membranous and cytoplasmic patterns in epithelial cells and on endothelia of stromal blood vessels. Compared with those in intraepithelial neoplasias, immunoscores were significantly increased in ISCC (P<0.0001 for epithelial and endothelial expression, respectively). High scoring was associated with International Federation of Gynecology and Obstetrics stages IB and higher. Immunoscores of epithelial and endothelial B7-H3 expression were correlated significantly (P=0.0358). Epithelial and endothelial expression of B7-H3 was inversely related with CD8(+) tumor-infiltrating lymphocyte (P<0.0001). Moderate/strong B7-H3 epithelial as well as endothelial expression was mutually increased with intermediate/strong phosphohistone H3 scores (P=0.0396 and P=0.0483, respectively). There was no statistical relation with survival; however, no patient with negative scoring died of her tumor. Our results indicate that B7-H3 expression in cervical ISCC may play an important role in overcoming CD8(+) T-cell immunoregulation to acquire aggressive growth.

B7-H3, which has been reported to be a co-regulatory ligand of the B7 family, can suppress T cell-mediated immunity and has also been reported to be expressed in many malignancies. In this study, we found that B7-H3 was primarily expressed in the cytoplasm of cervical cancer cells and was associated with deep stromal invasion (P=0.0013). The disease-free survival data showed that cervical cancer patients whose tumours were positive for B7-H3 expression had higher mortality rates compared with patients whose tumours lacked B7-H3 expression (P=0.0317), representing an advantage over P16 (P=0.3486). In contrast, the level of serum B7-H3 was low in cases of cervical intraepithelial neoplasia and cervical cancer. The silencing of B7-H3 in the SiHa, CaSki and H8 cell lines inhibited cell proliferation and enhanced apoptosis, while the over-expression of B7-H3 in HeLa cells showed inverse changes. These changes were partially due to the regulation of cell cycle- and apoptosis-related proteins, such as E2F, P21, P16, PARP-1, Caspase-8, Bax, Bcl-2 and Bcl-xl. The results of in vivo experiments revealed that the knockdown of B7-H3 in tumour cells suppressed SiHa cell growth in nude mice. Overall, B7-H3 is involved in the development and progression of cervical intraepithelial neoplasia and cervical cancer through its effects on the cell cycle and apoptosis, which are mediated via the E7/Rb pathway. B7-H3 also has the potential to be a useful prognostic marker for patients with cervical cancer.

B7-H3, a member from B7-family co-stimulatory ligands, plays an important role in adaptive immune responses. In addition, recent studies also demonstrated that B7-H3 could be highly expressed in various types of human cancers, and its expression level was significantly associated with cancer patients' clinicopathological parameters and postoperative prognoses. As of now, the exact role of B7-H3 expression in human esophageal cancer still remains elusive. In the present study, we characterized the B7-H3 expression in the human esophageal cancer cell line Eca-109 and TE-1, and in 174 cases of human esophageal cancer tissues, and to analyze its clinical implications and its correlation to T cell infiltration. By using the RNA interference method to down-regulate the B7-H3 expression in human esophageal cancer cell line Eca-109, we further studied the contribution of high B7-H3 expression to the biological features of this malignancy. Our results showed that B7-H3 was highly expressed in the cell line Eca-109 and TE-1, the high expression level of B7-H3 in esophageal cancer tissues was significantly associated with tumor invasion and patient's poor survival. Moreover, the higher B7-H3 expression was significantly and inversely correlated to the CD3(+)T cells infiltration in tumor nest of esophageal cancer tissues. We successfully constructed the recombinant lentivirus of siRNA targeting B7-H3, and the cellular studies showed that the down regulation of B7-H3 expression could suppress the proliferation, colony formation, migration and invasion in Eca-109 cells, which was consistent with the finding from the clinical sample cohort study. Collectively, the high B7-H3 expression was involved in the cancer progression of human esophageal cancer, and might contributed to the negative regulation of T-cell mediated antitumor response in tumor microenvironment, and the proliferation and mobility of esophageal cancer cells. The detailed mechanism and the potential value of clinical use targeting B7-H3 against human esophageal cancer merit further investigation.

B7-H3 is a tumor-promoting glycoprotein that is expressed at low levels in most normal tissues, but is overexpressed in various human cancers which is associated with disease progression and poor patient outcome. Although numerous publications have reported the correlation between B7-H3 and cancer progression in many types of cancers, mechanistic studies on how B7-H3 regulates cancer malignancy are rare, and the mechanisms underlying the role of B7-H3 in drug resistance are almost unknown. Here we report a novel finding that upregulation of B7-H3 increases the breast cancer stem cell population and promotes cancer development. Depletion of B7-H3 in breast cancer significantly inhibits the cancer stem cells. By immunoprecipitation and mass spectrometry, we found that B7-H3 is associated with the major vault protein (MVP) and activates MEK through MVP-enhancing B-RAF and MEK interaction. B7-H3 expression increases stem cell population by binding to MVP which regulates the activation of the MAPK kinase pathway. Depletion of MVP blocks the activation of MEK induced by B7-H3 and dramatically inhibits B7-H3 induced stem cells. This study reports novel functions of B7-H3 in regulating breast cancer stem cell enrichment. The novel mechanism for B7-H3-induced stem cell propagation by regulating MVP/MEK signaling axis independent of the classic Ras pathway may have important implications in the development of strategies for overcoming cancer cell resistance to chemotherapy.

B7-H3, also referred to as CD276, is a member of the B7 family of immune regulatory proteins. B7-H3 is overexpressed on many solid cancers, including prostate cancer, renal cell carcinoma, melanoma, squamous cell carcinoma of the head and neck, non-small cell lung cancer and breast cancer. Over-expression of B7-H3 is associated with disease severity, risk of recurrence and reduced survival. In this article, we report the preclinical development of MGC018, an antibody-drug conjugate targeted against B7-H3. MGC018 is comprised of the cleavable linker-duocarmycin payload, valine-citrulline-seco duocarmycin hydroxybenzamide azaindole (vc-seco-DUBA), conjugated to an anti-B7-H3 humanized IgG1/kappa monoclonal antibody through reduced interchain disulfides, with an average drug-to-antibody ratio of ~2.7. MGC018 exhibited cytotoxicity toward B7-H3-positive human tumor cell lines, and exhibited bystander killing of target-negative tumor cells when co-cultured with B7-H3-positive tumor cells. MGC018 displayed potent antitumor activity in preclinical tumor models of breast, prostate and lung cancer, as well as melanoma. Additionally, antitumor activity was observed toward patient-derived xenograft models of breast, prostate and head and neck cancer displaying heterogeneous expression of B7-H3. Importantly, MGC018 exhibited a favorable pharmacokinetic and safety profile in cynomolgus monkeys following repeat-dose administration. The antitumor activity observed preclinically with MGC018, together with the positive safety profile, provides evidence of a potentially favorable therapeutic index and supports the continued development of MGC018 for the treatment of solid cancers.

B7-H3 belongs to the B7 family of immune checkpoint proteins, which are important regulators of the adaptive immune response and emerging key players in human cancer. B7-H3 is a transmembrane protein expressed on the surface of tumor cells, antigen presenting cells, natural killer cells, tumor endothelial cells, but can also be present in intra- and extracellular vesicles. Additionally, B7-H3 may be present as circulating soluble isoforms in serum and other body fluids. B7-H3 is overexpressed in a variety of tumor types, in correlation with poor prognosis. B7-H3 is a promising new immunotherapy target for anti-cancer immune response, as well as being a potential biomarker. Besides its immunoregulatory role, B7-H3 has intrinsic pro-tumorigenic activities related to enhanced cell proliferation, migration, invasion, angiogenesis, metastatic capacity and anti-cancer drug resistance. B7-H3 has also been found to regulate key metabolic enzymes, promoting the high glycolytic capacity of cancer cells. B7-H3 receptors are still not identified, and little is known about the molecular mechanisms underlying B7-H3 functions. Here, we review the current knowledge on the involvement of B7-H3 in human cancer.

This study aimed to investigate the correlation between the expression of CD24 and B7-H3 in breast cancer tissues and the clinical significance. Expression of CD24 and B7-H3 in breast cancer and adjacent tissues were detected by immunohistochemistry. Quantitative PCR was used to detect the expression of CD24 and B7-H3 mRNA in breast cancer and adjacent tissues. The expression of CD24 and B7-H3 protein in breast cancer and adjacent tissues was detected by immunoblotting. The correlation between the expression levels of the two proteins was analyzed and the relationship between the expression of two proteins and the 5-year survival of breast cancer patients was investigated. CD24 and B7-H3 were positively expressed in breast cancer and adjacent tissues, the CD24-positive rate was 75.7 and 25.7%, respectively, and the B7-H3-positive rate was 56.8 and 43.2%, respectively, and the differences were statistically significant (P<0.05). The expression of CD24 was positively correlated with the expression of B7-H3 (Spearman's correlation coefficient r, 0.297; p=0.036). The positive and negative expression of CD24 and B7-H3 significantly affected the 5-year survival of breast cancer patients (P<0.05). Quantitative PCR results showed that the expression levels of CD24 and B7-H3 mRNA in breast cancer tissues were significantly higher than those in adjacent tissues (P<0.05). The expression levels of CD24 and B7-H3 protein in breast cancer tissues were also significantly higher than those in adjacent tissues (P<0.05). CD24 and B7-H3 were highly expressed in breast cancer, suggesting that both CD24 and B7-H3 were related to the development of breast cancer. Five-year survival analysis of breast cancer patients showed that the high expression of CD24 and B7-H3 were correlated with the poor prognosis of patients. Thus, CD24 and B7-H3 may become new targets for the treatment of breast cancer.

B7-H3, a member of the B7 family, has been reported to be highly expressed in colorectal cancer and is associated with poor prognosis and overall survival. In this study, we found that overexpression of B7-H3 protected SW80 and HCT8 cells from 5-fluorouracil (5-FU) using CCK-8 assays by inducing resistance to 5-FU chemotherapy. Further investigation has revealed elevated expression of thymidylate synthase (TS) and upregulation of the PI3-kinase (PI3K)/Akt pathway in B7-H3 overexpressing cells. The effects of B7-H3 on activation of the PI3K/Akt pathway and elevation of TS expression could be blocked by LY294002, a specific inhibitor of the PI3K signaling pathway. These results implied that B7-H3 can induce colorectal cancer cell resistance to 5-FU by increasing TS expression and PI3K/Akt/TS signaling and plays an important role during these processes. This study provides more proof concerning the non-immunology effect of B7 molecules, a reminder that both co-stimulatory or inhibitory effects and non-immunology effects should be devoted equal attention.

Among the main promising systems to triggering therapeutic antitumor immunity is the blockade of immune checkpoints. Immune checkpoint pathways regulate the control and eradication of infections, malignancies, and resistance against a host of autoantigens. Initiation point of the immune response is T cells, which have a critical role in this pathway. As several immune checkpoints are initiated by ligand-receptor interactions, they can be freely blocked by antibodies or modulated by recombinant forms of ligands or receptors. Antibodies against cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) were the first immunotherapeutics that achieved the US Food and Drug Administration approval. Preliminary clinical results with the blockers of additional immune checkpoint proteins, such as programmed cell death protein 1 (PD-1) indicate extensive and different chances to boost antitumor immunity with the objective of conferring permanent clinical effects. This study provides an overview of the immune checkpoint pathways, including CTLA-4, PD-1, lymphocyte activation gene 3, T-cell immunoglobulin and mucin domain 3, B7-H3, and diacylglycerol kinase α and implications of their inhibition in the cancer therapy.

Background: The tumor immune microenvironment is closely related to the malignant progression and treatment resistance of glioma. Long non-coding RNA (lncRNA) plays a regulatory role in this process. We investigated the pathological mechanisms within the glioma microenvironment and potential immunotherapy resistance related to lncRNAs.

Method: We downloaded datasets derived from glioma patients and analyzed them by hierarchical clustering. Next, we analyzed the immune microenvironment of glioma, related gene expression, and patient survival. Coexpressed lncRNAs were analyzed to generate a model of lncRNAs and immune-related genes. We analyzed the model using survival and Cox regression. Then, univariate, multivariate, receiver operating characteristic (ROC), and principle component analysis (PCA) methods were used to verify the accuracy of the model. Finally, GSEA was used to evaluate which functions and pathways were associated with the differential genes.

Results: Normal brain tissue maintains a low-medium immune state, and gliomas are clearly divided into three groups (low to high immunity). The stromal, immune, and estimate scores increased along with immunity, while tumor purity decreased. Further, human leukocyte antigen (HLA), programmed cell death-1 (PDL1), T cell immunoglobulin and mucin domain 3 (TIM-3), B7-H3, and cytotoxic T lymphocyte-associated antigen-4 (CTLA4) expression increases concomitantly with immune state, and the patient prognosis worsens. Five immune gene-related lncRNAs (AP001007.1, LBX-AS1, MIR155HG, MAPT-AS1, and LINC00515) were screened to construct risk models. We found that risk scores are related to patient prognosis and clinical characteristics, and are positively correlated with PDL1, TIM-3, and B7-H3 expression. These lncRNAs may regulate the tumor immune microenvironment through cytokine-cytokine receptor interactions, complement, and coagulation cascades, and may promote CD8 + T cell, regulatory T cell, M1 macrophage, and infiltrating neutrophils activity in the high-immunity group. In vitro, the abnormal expression of immune-related lncRNAs and the relationship between risk scores and immune-related indicators (PDL1, CTLA4, CD3, CD8, iNOS) were verified by q-PCR and immunohistochemistry (IHC).

Conclusion: For the first time, we constructed immune gene-related lncRNA risk models. The risk score may be a new biomarker for tumor immune subtypes and provide molecular targets for glioma immunotherapy.

Keywords: glioma; immune gene sets; lncRNA; risk score; tumor immune microenvironment.

Dendritic cells (DC) play a pivotal role in the initiation, maintenance and regulation of the immune response. Here we obtained the first evidence that DC, in the absence of any foreign antigens, induce the expression of B7 family costimulatory molecules, such as CD80, CD86, B7-H1, PD-L2, B7-H3, and B7RP-1, on autologous T lymphocytes. Cell-to-cell contact between DC and T cells was needed in order to obtain this expression on T cells. De novo expressed B7 molecules on T cells were functional since B7+ T cells were able to costimulate the proliferation of highly purified T cells. While both autologous and allogeneic DC were able to induce similar levels of costimulatory molecule expression, the chemokine receptor repertoire on B7+ T cells after interaction with DC varied depending on the presence of allo-antigens during the interaction (CCR7-, CCR5+) or the absence of antigens (CCR7+, CCR5-). In accordance with this different pattern of chemokine receptors in the two conditions, we propose that, after the encounter with DC in lymphoid organs, this peculiar T cell population should reside in the T cell areas of the lymph nodes or migrate to peripheral sites of inflammation, providing a second signal for activating or switching off, respectively, naive or peripheral effector T cells.

We examined the distribution of CD1a⁺ cells and CD8⁺ and CD4⁺ T lymphocytes in prostate cancer (PCa) and correlated these with clinicopathological parameters. We also investigated whether the distribution of these cells was related to the expression of the cell membrane protein B7-H3, a putative negative regulator of the immune response expressed on PCa cells. A cohort of 151 PCa patients treated with radical prostatectomy (RP) was followed prospectively from 1985 until 2006 with a median follow-up of 9 years. Whole-mount sections of PCa specimens were immunostained to identify immune cells. A low number of CD1a⁺ cells was significantly associated with a high Gleason score and high pathological stage of pT3. The number of CD1a⁺ cells correlated significantly with the number of intratumoral and stromal CD8⁺ and stromal CD4⁺ lymphocytes. Kaplan-Meier analysis showed a tendency toward impaired biochemical progression-free survival in patients with few CD1a⁺ cells within their RP specimens. The expression of B7-H3 correlated inversely with the number of CD1a⁺ cells and intratumoral CD4⁺ lymphocytes; there was a trend for a similar inverse relationship between B7-H3 expression and the number of CD8⁺ lymphocytes.

OBJECTIVE

To associate the global gene expression of B7/CD28 family transcripts with pathologic features of colon cancer, we determined the B7/CD28 family transcripts in peripheral blood mononuclear cells (PBMCs) from normal subjects and patients with adenomatous polyps and colon cancer, and correlated the results with pathologic features of colon cancer.

METHODS

PBMCs from age-matched normal subjects and patients with adenomatous polyps and colon cancer were analyzed for peripheral blood transcripts (PBTs) of B7/CD28 family using real-time PCR. Differences in expression levels of B7/CD28 PBTs across all cancer stages and between colon cancer patients with or without microscopic lymphovascular invasion (LVI) were analyzed.

RESULTS

The results showed a significant upregulation of PBTs of co-inhibitory molecules such as B7-H3 and PD-1 and a significant PBT downregulation of co-stimulatory molecules including CD28 and ICOS in colon cancer patients. Furthermore, the increase of B7-H3 PBT was strongly associated with tumor invasion (P = 0.025) and advanced TNM stages (P = 0.019), whereas the decline of co-stimulatory ligand B7-H2 PBT was related to regional lymph node metastasis (P = 0.028) and aggressive tumor invasion (P = 0.031). In addition, the ratios of PBT expression of CD28 family to B7 family such as CTLA-4 to B7-H2 and PD-1 to B7-H2 were significantly higher in colon cancer patients with microscopic LVI than in those without LVI (P = 0.001 and P = 0.016, respectively).

CONCLUSIONS

Our results suggest that B7/CD28 family PBTs may serve as valuable markers reflecting the pathological features of colon cancer.

OBJECTIVE

Although the mechanisms underlying the initiation and maintenance of inflammation in chronic rhinosinusitis are poorly understood, the activation of memory T cells within the nasal mucosa is thought to play an important role. T-cell activation requires specialized antigen processing and presentation of antigen by immunocompetent cells in the context of cell surface immune molecules. The purpose of this study was to investigate the expression of such molecules by human sinonasal epithelial cells grown in culture at the air-liquid interface (ALI).

METHODS

Middle meatal epithelium was obtained from six patients undergoing endoscopic sinus surgery. Dissociated epithelial cells were grown to confluence in serum-free, defined medium and transferred to filter inserts for culture at the ALI. Cells were harvested at 2 and 21 days of growth at the ALI and processed for real-time polymerase chain reaction (PCR). The presence and relative abundance of constitutively expressed mRNA for human leukocyte antigen (HLA)-B, HLA-DR, B7 to 1, B7 to 2, B7-H2, B7-H3, and cathepsin D were assessed.

RESULTS

After 2 days at the ALI, middle meatal epithelial cells demonstrated expression of genes for each of the antigen processing associated genes tested. The expression of HLA-B and HLA-DR increased significantly with cellular maturation at the ALI. Expression of HLA-DR and B7 to 1 increased with cytokine stimulation.

CONCLUSIONS

Primary human epithelial cells obtained from the middle meatus express genes associated with antigen presentation function. The pattern of gene expression is modulated by cytokine stimulation and changes as the cells differentiate at the ALI. These findings suggest that mature middle meatal epithelial cells have the cellular machinery to interact with T cells and therefore may be direct participants in the modulation of T-cell activity in chronic sinusitis.

OBJECTIVE

The high rate of relapse in patients with advanced ovarian cancer likely reflects the chemoresistance of cancer initiating cells (CICs). We evaluated the anti-tumor activity of monoclonal antibody (mAb) 376.96, which recognizes a B7-H3 epitope expressed on ovarian carcinoma cells (OCCs), in combination with the tyrosine kinase inhibitor Sunitinib and chemotherapy on chemosensitive and chemoresistant cells and CICs.

METHODS

Eight ovarian cancer cell lines including platinum- and taxane-resistant cell lines were analyzed by flow cytometry to establish expression of the mAb 376.96-defined-B7-H3-epitope on differentiated ovarian cancer cells and CICs. Samples from 10 ovarian cancer patients were analyzed via immunohistochemistry for mAb 376.96-defined-B7-H3-epitope expression. In vitro studies assessed mAb 376.96 alone and in combination with Sunitinib on the growth of chemosensitive and chemoresistant cell lines and on the content of CICs.

RESULTS

The mAb-376.96-defined-B7-H3 epitope is expressed on both differentiated cells and CICs in chemosensitive and chemoresistant ovarian cancer cell lines and 10 patient derived ovarian cancer tumors. In vitro treatment of chemoresistant cell lines with mAb 376.96 resulted in decreased cell viability. mAb 376.96 enhanced the cytotoxicity of Sunitinib and reduced the content of CICs.

CONCLUSIONS

The mAb-376.96-defined-B7-H3-epitope was found to be expressed on both differentiated ovarian cancer cells and CICs in chemosensitive and chemoresistant ovarian cancer cell lines. mAb 376.96 inhibited the in vitro growth of chemosensitive and chemoresistant OCCs and reduced the content of CICs when used with Sunitinib. Further studies examining B7-H3 as a potential target of mAb-based immunotherapy for this type of malignancy are warranted.