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Background Acute lymphoblastic leukemia (ALL) is a hematologic malignancy characterized by poor outcomes in adults. Traditional diagnostic and prognostic markers take into account clinical data but also rely heavily on expensive and invasive tests such as bone marrow studies with cytogenetics. CD155 is an adhesion molecule that also modulates immune response in malignancy. Previous studies have shown that serum CD155 (sCD155) levels are higher in patients with malignancies, and have demonstrated a correlation between higher levels of sCD155 and poor outcomes. This study investigated the diagnostic and prognostic value of sCD155 in adult patients with acute lymphoblastic leukemia. Methodology 32 adult patients with acute lymphoblastic leukemia and 15 control patients were enrolled in this study. Clinical and outcome data were collected from patients and a blood sample from patients and controls was collected with ELISA testing for sCD155 levels. Results sCD155 was found to be significantly higher in patients than controls (P<0.05) and was significantly associated with bone marrow aspirate blast count. It was not associated with other clinical parameters including Sex, age, initial CBC parameter counts, presence of lymphadenopathy, presence of CNS infiltration, presence of Philadelphia chromosome, type of ALL, or risk stratification of ALL besides being associated with hepatosplenomegaly. ROC curve showed high sensitivity and specificity of sCD155 and Kaplan Meir curve showed a trend towards worse outcomes in patients with high sCD155 but it was not statistically significant. Conclusion sCD155 remains a promising marker for diagnosis of ALL but further studies are needed to confirm prognostic value. [ABSTRACT FROM AUTHOR]

CD155, also known as the poliovirus receptor, is an adhesion molecule often overexpressed in tumors of different origins where it promotes cell migration and proliferation. In addition to this pro-tumorigenic function, CD155 plays an immunomodulatory role during tumor progression since it is a ligand for both the activating receptor DNAM-1 and the inhibitory receptor TIGIT, expressed on cytotoxic innate and adaptative lymphocytes. DNAM-1 is a well-recognized receptor involved in anti-tumor immune surveillance. However, in advanced tumor stages, TIGIT is up-regulated and acts as an immune checkpoint receptor, counterbalancing DNAM-1-mediated cancer cell clearance. Pre-clinical studies have proposed the direct targeting of CD155 on tumor cells as well as the enhancement of DNAM-1-mediated anti-tumor functions as promising therapeutic approaches. Moreover, immunotherapeutic use of anti-TIGIT blocking antibody alone or in combined therapy has already been included in clinical trials. The aim of this review is to summarize all these potential therapies, highlighting the still controversial role of CD155 during tumor progression. [ABSTRACT FROM AUTHOR]

Background: Medulloblastoma is the most common pediatric malignant brain tumor, consisting of four molecular subgroups (WNT, SHH, Group 3, Group 4) and 12 subtypes. Expression of the cell surface poliovirus receptor (PVR), CD155, is necessary for entry of the viral immunotherapeutic agent, PVSRIPO, a polio:rhinovirus chimera. CD155, physiologically expressed in the mononuclear phagocytic system, is widely expressed ectopically in solid tumors. The objective of this study is to elucidate CD155 expression as both a receptor for PVSRIPO and a therapeutic target in medulloblastoma. Methods: PVR mRNA expression was determined in several patient cohorts and human medulloblastoma cell lines. Patient samples were also analyzed for CD155 expression using immunohistochemistry and cell lines were analyzed using Western Blots. CD155 was blocked using a monoclonal antibody and cell viability, invasion, and migration were assessed. Results and Discussion: PVR mRNA expression was highest in the WNT subgroup and lowest in Group 4. PVR expression in the subgroups of medulloblastoma were similar to other pediatric brain and non-brain tumors. PVR expression was largely not associated with subgroup or subtype. Neither PVR protein expression intensity nor frequency were associated with overall survival. PVR expression was elevated in Group 3 patients with metastases but there was no difference in paired primary and metastatic medulloblastoma. Blocking PVR resulted in dose-dependent cell death, decreased invasion in vitro, and modestly inhibited cell migration. Conclusions: CD155 is expressed across medulloblastoma subgroups and subtypes. Blocking CD155 results in cell death and decreased cellular invasion. This study provides rationale for CD155-targeting agents including PVSRIPO and antibody-mediated blockade of CD155. [ABSTRACT FROM AUTHOR]

Gastric cancer (GC) is the fourth leading cause of cancer death worldwide. Due to the complex tumor microenvironment (TME), the efficacy of immunotherapy in GC has not met expectations. Malignant changes in the TME induce endoplasmic reticulum stress (ERS). ERS can be transmitted between tumor cells and tumor-associated macrophages (TAMs), promoting tumor immune escape, but the specific mechanism in GC remains unclear. We established a TAM model of transmitted ERS (TERS), and iTRAQ proteomic analysis identified overexpressed proteins. The overexpression of poliovirus receptor (PVR) was screened while flow cytometry and ELISA showed that PVR mediated the immunosuppressive function of TAMs by downregulating the proliferative activity and cytotoxicity of cocultured CD8+ T lymphocytes. With EMSA and dual-luciferase reporter assays, we confirmed that erythropoietin-producing hepatocellular receptor A2 (EphA2) affected PVR expression by increasing the transcriptional activity of activator protein-1 (AP-1). MFC cells were mixed with EphA2 knockdown or control RAW264.7 cells to establish subcutaneous tumor models with or without tunicamycin treatment in vivo. The vivo experiments revealed that ERS promoted subcutaneous xenograft growth, which was reversed by EphA2 knockdown. Clinically, GC patients with high expression of PVR and EphA2 tended to have an immunosuppressive TME, which were determined by immunohistochemical and immunofluorescence analyses. In conclusion, the transcriptional activity of AP-1 is upregulated in ERS-transmitted TAMs through EphA2 to increase PVR expression, which promotes immune escape in GC. Our study provides a new perspective on the role of ERS in tumor immunity. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) is a prevalent malignancy with poor prognosis. As a cell adhesion molecule, poliovirus receptor (PVR/CD155) is abnormally overexpressed in tumour cells, and related to tumour proliferation and invasion. However, the potential role and mechanism of CD155 have not yet been elucidated in HCC. Methods: Immunohistochemistry, RT‐PCR and Western blot assays were used to determine CD155 expression in HCC cell lines and tissues. Cell Counting Kit‐8 and colony formation assays were used to examine cell proliferation. Transwell and wound healing assays were used to evaluate cell migration and invasion. Cell apoptosis and cycle distribution were assessed by flow cytometry. Cox regression and Kaplan–Meier analyses were performed to explore the clinical significance of CD155. The role of CD155 in vivo was evaluated by establishing liver orthotropic xenograft mice model. RNA sequencing, bioinformatics analysis and co‐immunoprecipitation assay were used to explore the downstream signalling pathway of CD155. Results: CD155 was upregulated in HCC tissues and represented a promising prognostic indicator for HCC patients (n = 189) undergoing curative resection. High CD155 expression enhanced cell proliferation, migration and invasion, and contributed to cell survival in HCC. CD155 overexpression also induced epithelial–mesenchymal transition in HCC cells. CD155 function in HCC involved SRC/p38 MAPK signalling pathway. CD155 interacted with SRC homology‐2 domain of SRC and promoted SRC activation, further inhibiting the downstream p38 MAPK signalling pathway in HCC. Conclusions: CD155 promotes HCC progression via the SRC/p38 MAPK signalling pathway. CD155 may represent a predictor for poor postsurgery prognosis in HCC patients. [ABSTRACT FROM AUTHOR]

Simple Summary: The presence of the poliovirus receptor (known as cluster of differentiation 155 (CD155)) in human cancer is an unfavorable prognostic marker. We investigated whether CD155 expression, divided into membranous and cytoplasmic types, affects the prognosis of bladder cancer (BC) in terms of recurrence-free survival (RFS) and cancer-specific survival (CSS). We found that membranous CD155 (mCD155)-positive cases had shorter periods of both RFS and CSS, whereas there was no association between cytoplasmic CD155 (cCD155) and survival outcomes. The results showed that CD155, especially mCD155, may serve as a poor prognostic marker in BC. Objective: To investigate the relationship between clinicopathological findings and membranous CD155 (mCD155) or cytoplasmic CD155 (cCD155) expression in bladder cancer (BC). Methods: We retrospectively analyzed 103 patients with BC who underwent radical cystectomy between 1990 to 2015 at Kitasato University Hospital. Immunohistochemical staining was performed to evaluate CD155 expression in tumor cells. Cases with > 10% expression on the membrane or cytoplasm of tumor cells were positive. The Fisher′s exact test was used for categorical variables and the Kaplan–Meier method was used for survival outcomes. Univariate and multivariate Cox regression hazard models were used to evaluate the survival risk factors. Results: Cases that were mCD155-positive were associated with high-grade tumors (p = 0.02), nodal status (p < 0.01), and pT stage (p = 0.04). No association with any clinicopathological factor was observed in the cCD155 cases. Kaplan–Meier analysis showed that mCD155-positive cases had shorter periods of recurrence-free survival (p = 0.015) and cancer-specific survival (p = 0.005). Only nodal status was an independent predictor for both cancer-specific survival and recurrence-free survival in multivariate analysis (p = 0.02 and p < 0.01, respectively). Conclusion: mCD155 expression may be a marker of an aggressive phenotype and a poor prognosis in patients with BC. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to investigate the prognostic value of multiple immune cell markers including programmed death-ligand 1 (PD-L1) and poliovirus receptor (PVR) in head and neck squamous cell carcinoma (HNSCC) using archival tumor tissues Methods: Patients diagnosed with HNSCC who have undergone surgical resection in 2005–2012 were included. Correlations between PVR and PD-L1 expression and patient characteristics were analyzed by analysis of variance. The Kaplan–Meier method and log-rank test were used to estimate survival. P values < 0.05 were considered statistically significant. Results: In total, 375 primary tumor tissues were analyzed using immunohistochemistry. High PVR expression was associated with a poor prognosis in terms of overall survival (OS) and recurrence-free survival (RFS), and tumors with high PVR expression were associated with a short OS. PD-L1 tumor expression did not have a prognostic impact on survival. Univariate analysis revealed that OS and RFS were affected by age and p16 and PVR expression; multivariate analysis revealed that age and p16 and PVR expression were the most important determinants of RFS. Conclusion: PVR overexpression is a poor prognostic factor in patients with HNSCC and co-targeting PVR and PD-L1 may be a promising therapeutic option that needs further investigation. [ABSTRACT FROM AUTHOR]

BackgroundBladder cancer is an aggressive and heterogeneous disease associated with high morbidity and mortality. And poliovirus receptor (PVR or CD155) played crucial roles in tumor immune microenvironment and cancer development. However, their association remains obscure.MethodsA total of 797 patients from TCGA and GEO databases were employed in our study, in which 285 cases were set as the training cohort and 512 were defined as the validation cohort. Our own Xiangya cohort with 57 samples was also used for the validation. Survival differences were evaluated by Kaplan-Meier analysis between groups. The immune infiltration was evaluated by ESTIMATE, TIMER, and CIBERSORT algorithms. The risk signature was constructed by LASSO Cox regression analysis. And a nomogram model was generated subsequent to the multivariate Cox proportional hazards analysis to predict 3- and 5-year survival of patients with bladder cancer.ResultsPVR was overexpressed across various cancers including bladder cancer and related to poorer overall survival in bladder urothelial carcinoma (BLCA). Samples with higher World Health Organization (WHO) grade or higher tumor stage tended to express higher level of PVR. And PVR-related genes were involved in several immune processes and oncological pathways. When the patients were divided into low- and high-risk groups based on their risk scores, we found that patients in the high-risk group had shorter overall survival time. Besides, samples with high risk were consistently correlated with tumor hallmarks and higher abundance of immune infiltration. Additionally, chemotherapy showed potent efficacy in high-risk group. Moreover, a nomogram including clinicopathologic features and the established risk signature could predict 3- and 5-year survival in patients with bladder cancer.ConclusionOur study revealed that PVR was overexpressed and related to poor prognosis in bladder cancer. A risk signature and nomogram model based on PVR-related genes could predict the prognosis and therapeutic efficacy and were also associated with the immune infiltration in bladder cancer.

Background: Bladder cancer is an aggressive and heterogeneous disease associated with high morbidity and mortality. And poliovirus receptor (PVR or CD155) played crucial roles in tumor immune microenvironment and cancer development. However, their association remains obscure. Methods: A total of 797 patients from TCGA and GEO databases were employed in our study, in which 285 cases were set as the training cohort and 512 were defined as the validation cohort. Our own Xiangya cohort with 57 samples was also used for the validation. Survival differences were evaluated by Kaplan-Meier analysis between groups. The immune infiltration was evaluated by ESTIMATE, TIMER, and CIBERSORT algorithms. The risk signature was constructed by LASSO Cox regression analysis. And a nomogram model was generated subsequent to the multivariate Cox proportional hazards analysis to predict 3- and 5-year survival of patients with bladder cancer. Results: PVR was overexpressed across various cancers including bladder cancer and related to poorer overall survival in bladder urothelial carcinoma (BLCA). Samples with higher World Health Organization (WHO) grade or higher tumor stage tended to express higher level of PVR. And PVR -related genes were involved in several immune processes and oncological pathways. When the patients were divided into low- and high-risk groups based on their risk scores, we found that patients in the high-risk group had shorter overall survival time. Besides, samples with high risk were consistently correlated with tumor hallmarks and higher abundance of immune infiltration. Additionally, chemotherapy showed potent efficacy in high-risk group. Moreover, a nomogram including clinicopathologic features and the established risk signature could predict 3- and 5-year survival in patients with bladder cancer. Conclusion: Our study revealed that PVR was overexpressed and related to poor prognosis in bladder cancer. A risk signature and nomogram model based on PVR -related genes could predict the prognosis and therapeutic efficacy and were also associated with the immune infiltration in bladder cancer. [ABSTRACT FROM AUTHOR]

Recent studies have shown that aberrant expression of tight junction proteins (TJP) contributes to malignant potential of various cancers. In the present study, we investigated the expression of junctional adhesion molecule‐A (JAM‐A), one of the transmembrane TJP, in uterine cervical adenocarcinoma and the significance of its expression for malignancy. Immunohistochemistry on human surgical specimens showed that JAM‐A was aberrantly expressed in neoplastic regions including adenocarcinoma in situ (AIS). Knockout of JAM‐A significantly suppressed cell proliferation and colony‐forming and migration abilities. We also showed that an antibody specific to an extracellular region of JAM‐A reduced cell proliferation ability and that loss of JAM‐A increased drug sensitivity of cervical adenocarcinoma cells. Based on a comprehensive proteome analysis, we found that poliovirus receptor (PVR/CD155) was regulated by JAM‐A and formed a physical interaction with JAM‐A. In human surgical specimens, PVR/CD155 expression was significantly correlated with some clinicopathological features and prognosis of cervical adenocarcinoma. Interestingly, most of the PVR/CD155‐positive cases expressed a high level of JAM‐A, and patients with the expression pattern of PVR/CD155 positive/JAM‐A high had significantly shorter periods of relapse‐free survival (P =.00964) and overall survival (P =.0204) than those for the other patients. Our observations suggest that aberrant expression of JAM‐A promotes malignancy of uterine cervical adenocarcinoma by regulation of PVR/CD155, and JAM‐A is therefore a potential therapeutic target for this malignancy. [ABSTRACT FROM AUTHOR]

Introduction: Poliovirus receptor (PVR) is a tumor promoter and a regulatory checkpoint that enhances immunosuppression. We investigated PVR expression by applying immunohistochemistry (IHC) staining. A positive association existed between PVR expression and cytotoxic T lymphocyte-associated antigen 4 (CTLA4) expression in patients with surgically resected non-small-cell lung cancer (NSCLC). PVR expression is a prognosis predictor of lung adenocarcinoma. Purpose: To investigate the prognostic significance of PVR expression and CTLA4 expression for surgically resected NSCLC. Patients and methods: The medical records of 108 Chinese patients with primary NSCLC who underwent surgery were retrospectively reviewed. The expression of PVR and CTLA4 were measured through IHC. Clinical characteristics, the association between PVR and CTLA4, and the prognostic significance of PVR were analyzed. Results: A significant positive association was observed between PVR and CTLA4 expression in NSCLC (P = 0.016). PVR had a high positive rate among females, nonsmokers, and patients with adenocarcinoma and advanced lung cancer. The overall survival (OS) of patients with negative PVR expression was significantly longer than that of patients with positive PVR expression (P = 0.049), especially among females (P = 0.03) and nonsmokers (P = 0.025). Multivariate analysis results showed that advanced tumor stage and PVR expression were independent prognosis predictors of poor OS. Conclusion: PVR can potentially serve as a prognostic predictor and biomarker for NSCLC and cancer anti-CTLA4 immunotherapy response. [ABSTRACT FROM AUTHOR]

Recent studies have revealed that tumor immunotherapy resistance is influenced by ADAR-mediated RNA editing, but its targets remain unelucidated. Our current study identified the poliovirus receptor (PVR) oncogene, which encodes an immune checkpoint in colorectal cancer (CRC), as a potential target for RNA editing. We performed transcriptome sequencing analysis and experimental validation in two Chinese CRC cohorts. PVR and ADAR expressions significantly increased in CRC tumors and showed positive correlations in both cohorts, coupled with upregulated PVR RNA editing in CRC tumors. Manipulation of ADAR expression by over-expression or knockdown substantially changed PVR expression and RNA editing in HTC116 CRC cells. Luciferase reporter and actinomycin D assays further revealed that RNA editing in PVR 3′-UTR could upregulate PVR RNA expression, probably by increasing the RNA stability. By increasing PVR expression, ADAR-mediate RNA editing might contribute to tumor- and immune-related gene functions and pathways in CRC. Moreover, a signature combining PVR RNA editing and expression showed promising predictive performance in CRC diagnosis in both Chinese CRC cohorts. Our findings thus highlight the importance of ADAR-mediated RNA editing in PVR up-regulation in CRC tumors and provide new insight into the application of PVR RNA editing as a novel diagnostic biomarker for CRC. • Immune checkpoint PVR was identified as a novel target of ADAR-mediated RNA editing in two Chinese CRC cohorts. • Elevated ADAR expression significantly upregulated PVR RNA editing and expression in CRC. • RNA editing in the PVR 3′-UTR significantly increased the RNA expression, probably by increasing RNA stability. • A signature combining PVR RNA editing and expression showed promising performance in CRC diagnosis in both Chinese cohorts. [ABSTRACT FROM AUTHOR]

Rat glioma cell line C6 expressing human poliovirus receptor (PVR) and susceptible to polioviruses (C6-PVR-BFP) was used to produce a clone with knockout of IFNα/β (Ifnar1) receptor subunit 1 gene (Ifnar1). The sensitivity of C6-PVR-BFP cells to the vaccine strain of poliovirus type 3 (PV3) depended on the signaling pathways of the cell response to type 1 IFN. Using the model of subcutaneous tumor xenografts, we demonstrated oncolytic activity of PV3 against C6-PVR-BFP cells that depended on the expression of PVR and increased considerably upon disturbances in IFN response pathways. [ABSTRACT FROM AUTHOR]

Context: Poliovirus (PV) receptor (CD155) is expressed on several kinds of cells and exerts diverse functions. Various investigations have confirmed that changes in CD155 expression in cancer cell lines affect metastasis, proliferation, and migration.Aims: The purpose of the present study was to investigate the CD155 transcript and protein expression in human colon adenocarcinoma cell lines in comparison to normal fetal human colon (FHC) cells.Materials and Methods: The CD155 expression level in four human adenocarcinoma cell lines and normal colon cell line were assessed using the SYBR green quantitative real-time polymerase chain reaction (PCR) and flowcytometry.Results: The results of real-time PCR indicated that CD155 was significantly overexpressed in all human adenocarcinoma cell lines (P = 0.000). The highest and the lowest expression level of CD155 messenger RNA was observed in SW480 and HT29 cell lines by 491.14, and 12.04 fold changes, respectively, in comparison with the human normal cell line (FHC). Results of flowcytometry indicate that protein was strongly expressed in cancer cell lines. SW480 cells showed the highest CD155 protein expression level of 98.1%, whereas this protein expression was 1.3% in human normal colon cell line (FHC). Totally, these data indicate that CD155 expression is significantly elevated in cancer cell lines.Conclusions: The preferential expression of CD155 on cancer cell lines rather than on normal cell line suggests that CD155 could be targeted for future PV virotherapy. [ABSTRACT FROM AUTHOR]

A humanized line of rat C6 glioma cells expressing human poliovirus receptor was obtained and tested for the sensitivity to oncolytic effects of vaccine strains of type 1, 2, and 3 polioviruses. Presentation of the poliovirus receptor on the surface of C6 glioma cells was shown to be a necessary condition for the interaction of cells with polioviruses, but insufficient for complete poliovirus oncolysis. [ABSTRACT FROM AUTHOR]

Background & objectives: It is important to understand the role of cell surface receptors in susceptibility to infectious diseases. CD155 a member of the immunoglobulin super family, serves as the poliovirus receptor (PVR). Heterozygous (Ala67Thr) polymorphism in CD155 has been suggested as a risk factor for paralytic outcome of poliovirus infection. The present study pertains to the development of a screening test to detect the single nucleotide (SNP) polymorphism in the CD155 gene. Methods: New primers were designed for PCR, sequencing and SNP analysis of Exon2 of CD155 gene. DNAs extracted from either whole blood (n=75) or cells from oral cavity (n=75) were used for standardization and validation of the SNP assay. DNA sequencing was used as the gold standard method. Results: A new SNP assay for detection of heterozygous Ala67Thr genotype was developed and validated by testing 150 DNA samples. Heterozygous CD155 was detected in 27.33 per cent (41/150) of DNA samples tested by both SNP detection assay and sequencing. Interpretation & conclusions: The SNP detection assay was successfully developed for identification of Ala67Thr polymorphism in human PVR/CD155 gene. The SNP assay will be useful for large scale screening of DNA samples. [ABSTRACT FROM AUTHOR]

Although T cells can exert potent anti-tumor immunity, a subset of T helper (Th) cells producing interleukin-22 (IL-22) in breast and lung tumors is linked to dismal patient outcome. Here, we examined the mechanisms whereby these T cells contribute to disease. In murine models of lung and breast cancer, constitutional and T cell-specific deletion of Il22 reduced metastases without affecting primary tumor growth. Deletion of the IL-22 receptor on cancer cells decreases metastasis to a degree similar to that seen in IL-22-deficient mice. IL-22 induced high expression of CD155, which bound to the activating receptor CD226 on NK cells. Excessive activation led to decreased amounts of CD226 and functionally impaired NK cells, which elevated the metastatic burden. IL-22 signaling was also associated with CD155 expression in human datasets and with poor patient outcomes. Taken together, our findings reveal an immunosuppressive circuit activated by T cell-derived IL-22 that promotes lung metastasis. [Display omitted] • IL-22 from Th cells acts on IL-22RA1+ tumor cells to promote lung metastases • Mechanistically, IL-22 induces overexpression of CD155 on tumor cells • Excessive CD155 promotes internalization of CD226 in NK cells, rendering them inert • IL-22-CD155 signature governs early-stage lung and breast cancer patients' survival Metastatic disease is the terminal and most lethal stage of cancer. Briukhovetska et al. find that interleukin-22 produced by Th cells increases the expression of CD155 in cancer cells, which in turn abrogates NK cell function by promoting the internalization of the activating receptor CD226. This axis promotes an immunosuppressive niche that enables lung metastases. [ABSTRACT FROM AUTHOR]

Background. Israel has >95% polio vaccine coverage with the last 9 birth cohorts immunized exclusively with inactivated polio vaccine (IPV). Using acute fiaccid paralysis and routine, monthly countrywide environmental surveillance, no wild poliovirus circulation was detected between 1989 and February 2013, after which wild type 1 polioviruses South Asia genotype (WPV1-SOAKS) have persistently circulated in southern Israel and intermittently in other areas without any paralytic cases as determined by intensified surveillance of environmental and human samples. We aimed to characterize antigenic and neuro virulence properties of WPV1-SOAS silently circulating in a highly vaccinated population. Methods. WPV1-SOAS capsid genes from environmental and stool surveillance isolates were sequenced, their neuro-virulence was determined using transgenic mouse expressing the human poliovirus receptor (Tg21-PVR) mice, and their antigenicity was characterized by in vitro neutralization using human sera, epitope-specific monoclonal murineanti-oral poliovirus vaccine (OPV) antibodies, and sera from IPV-immunized rats and mice. Results. WPV1 amino acid sequences in neutralizing epitopes varied from Sabin 1 and Mahoney, with little variation among WPV1 isolates. Neutralization by monoclonal antibodies against 3 of 4 OPV epitopes was lost. Three-fold lower geometric mean titers (Z = -4.018; P < .001, Wilcoxon signed-rank test) against WPV1 than against Mahoney in human serum correlated with 4-to 6-fold lower neutralization titers in serum from IPV-immunized rats and mice. WPV1-SOAS isolates were neurovirulent (50% intramuscular paralytic dose in Tg21-PVR mice: log107.0). IPV-immunized mice were protected against WPV1-induced paralysis. Conclusions. Phenotypic and antigenic profile changes of WPV1-SOAS may have contributed to the intense silent transmission, whereas the reduced neurovirulence may have contributed to the absence of paralytic cases in the background of high population immunity. [ABSTRACT FROM AUTHOR]

Poliovirus receptor ( PVR), regulator of G-protein signaling-11 ( RGS11), and erythrocyte protein band-4.1-like 3 ( EPB41L3) have been proposed to function in follicular maturation in mouse models. We have examined their expression in human mural (mGCs) and cumulus granulosa cells (CCs). Expression of PVR and RGS11 in mGCs decreased in medium-sized follicles compared to small follicles of IVM cycles and increased again in large follicles. Luteinization caused decreased expression of both PVR and RGS11. In vitro incubation of mGCs with progesterone-rich conditioned media decreased expression of RGS11 without affecting PVR levels. Inhibition of progesterone signaling enhanced expression of both RGS11 and PVR. Expression in CCs was examined by means of global transcriptome sequencing analysis RGS11 and EPB41L3 increased in CCs during follicular maturation while PVR levels did not change. In conclusion, during human follicular maturation there are significant changes in expression of PVR, RGS11 and EPB41L3, possibly regulated by progesterone. [ABSTRACT FROM AUTHOR]

In humans, paralytic poliomyelitis results from the invasion of the central nervous system by circulating poliovirus (PV) via the blood-brain barrier (BBB). After the virus enters the central nervous system (CNS), it replicates in neurons, especially in motor neurons (MNs), inducing the cell death that causes paralytic poliomyelitis. Along with this route of dissemination, neural pathway has been reported in humans, monkeys, and PV-sensitive human PV receptor (hPVR/CD155)-transgenic (Tg) mice. We demonstrated that a fast retrograde axonal transport process is required for PV dissemination through the sciatic nerve of hPVR-Tg mice and that intramuscularly inoculated PV causes paralysis in a hPVR-dependent manner. We also showed that hPVR-independent axonal transport of PV exists in hPVR-Tg and non-Tg mice, indicating that several different pathways for PV axonal transport exist in these mice. Circulating PV after intravenous inoculation in mice cross the BBB at a high rate in a hPVR-independent manner. Recently, we identified transferrin receptor 1 (TfR1) of mouse brain capillary endothelial cells as a binding protein to PV, implicating that TfR1 is a possible receptor for PV to permeate the BBB.

Abstract: Nectin-2, also known as poliovirus receptor-related 2 or CD112, has been identified in many animals and plays a crucial role in cell recognition and adhesion. Here we report the identification of two porcine Nectin-2 (poNectin-2) isoforms. The open reading frame (ORF) of 1440 nucleotides (nt) of poNectin-2α encodes 479 amino acids (aa). poNectin-2δ gene consists of 1620nt of ORF with 539aa. The deduced aa sequences of poNectin-2α and poNectin-2δ gene exhibit high identity with human (74% and 79%) and mouse (71% and 76%) orthologs, respectively. The ectodomains of deduced poNectin-2 protein share the structural feature of mammalian Nectin-2, including a conserved cysteine skeleton important for the formation of the three-dimensional structure. RT-PCR analysis showed that the mRNA of both poNectin-2 isoforms was broadly expressed in various tissues and cells. poNectin-2 gene was mapped to chromosome 6q21. Information from this study will help to elucidate the Nectin-2 pathway in xenotransplant immunity. [Copyright &y& Elsevier]

Necl-5 is an immunoglobulin (Ig)-like molecule that was originally identified as a poliovirus receptor and is often upregulated in cancer cells. We recently found that it colocalizes with integrin αvβ3 at the leading edges of moving cells and enhances growth factor-induced cell movement and proliferation. Upon cell–cell contact, Necl-5 is removed from the cell surface by its trans-interaction with the cell adhesion molecule nectin-3, resulting in reduced cell movement and proliferation. Here, we investigated the role of Necl-5 in the interaction of cancer cells with platelets. Necl-5 was upregulated in CT26 cells, a colon adenocarcinoma cell line. When CT26 cells were injected into the tail vein of mice, they were arrested in the pulmonary vessels by adhering to platelets and subsequently metastasized to the lungs. Overexpression of Necl-5 in CT26 cells enhanced this metastasis, while inhibition of the trans-interaction of Necl-5 with CD226 by an anti-Necl-5 monoclonal antibody reduced the metastasis. Depletion of platelets by treatment with a rabbit anti-mouse platelet serum reduced the Necl-5-enhanced metastasis in mice. Thus, the trans-interaction of upregulated Necl-5 in cancer cells with its counter-receptor in platelets, probably CD226, is critical for efficient metastasis of cancer cells to the lungs.Oncogene (2008) 27, 264–273; doi:10.1038/sj.onc.1210645; published online 16 July 2007 [ABSTRACT FROM AUTHOR]

Abstract: Normal cells show contact inhibition of cell movement and proliferation, but this is lost following transformation. We found that Necl-5, originally identified as a poliovirus receptor and up-regulated in many cancer cells, enhances growth factor-induced cell movement and proliferation. We showed that when cells contact other cells, Necl-5 interacts in trans with nectin-3 and is removed by endocytosis from the cell surface, resulting in a reduction of cell movement and proliferation. We show here that up-regulation of the gene encoding Necl-5 by the oncogene V12-Ki-Ras causes enhanced cell movement and proliferation. Upon cell–cell contact, de novo synthesis of Necl-5 exceeds the rate of Necl-5 endocytosis, eventually resulting in a net increase in the amount of Necl-5 at the cell surface. In addition, expression of the gene encoding nectin-3 is markedly reduced in transformed cells. Thus, up-regulation of Necl-5 following transformation contributes to the loss of contact inhibition in transformed cells. [Copyright &y& Elsevier]