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The article provides information on the monoclonal antibodies 1B3, 3B3, HAb18Gedomab1 and HAbGedomab2. The Sp2/0 myeloma cell line is used for fusion. The specificity of these antibodies was determined by Western-blot assay, flow cytometry and immunoflorescent staining. These antibodies are available as tissue culture supernatant.

Rapid advancements in next generation sequencing (NGS) technologies, coupled with the dramatic decrease in cost, have made NGS one of the leading approaches applied in cancer research. In addition, it is increasingly used in clinical practice for cancer diagnosis and treatment. Somatic (cancer-only) single nucleotide variants and small insertions and deletions (indels) are the simplest classes of mutation, however, their identification in whole exome sequencing data is complicated by germline polymorphisms, tumor heterogeneity and errors in sequencing and analysis. An increasing number of software and methodological guidelines are being published for the analysis of sequencing data. Usually, the algorithms of MuTect, VarScan and Genome Analysis Toolkit are applied to identify the variants. However, one of these algorithms alone results in incomplete genomic information. To address this issue, the present study developed a systematic pipeline for analyzing the whole exome sequencing data of hepatocellular carcinoma (HCC) using a combination of the three algorithms, named the three-caller pipeline. Application of the three-caller pipeline to the whole exome data of HCC, improved the detection of true positive mutations and a total of 75 tumor-specific somatic variants were identified. Functional enrichment analysis revealed the mutations in the genes encoding cell adhesion and regulation of Ras GTPase activity. This pipeline provides an effective approach to identify variants from NGS data for subsequent functional analyses. [ABSTRACT FROM AUTHOR]

Activated hepatic stellate cells (HSCs) release pro-inflammatory and pro-fibrogenic factors. CXC chemokine-ligand-1 (CXCL1) is expressed on HSCs. We previously found that the CD147 is overexpressed in activated HSCs. In this study, we showed an important role of CD147 in promoting liver fibrosis by activating HSCs and upregulating expression of chemokines. Specifically, we found that CD147 specific deletion in HSCs mice alleviated CCl4-induced liver fibrosis and inhibited HSCs activation. Overexpression of CD147 upregulated the secretion of CXCL1. Meanwhile, CXCL1 promoted HSCs activation through autocrine. Treating with PI3K/AKT inhibitor could effectively suppress CD147-induced CXCL1 expression. Taken together, these findings suggest that CD147 regulates CXCL1 release in HSCs by PI3K/AKT signaling. Inhibition of CD147 attenuates CCl4-induced liver fibrosis and inflammation. Therefore, administration of targeting CD147 could be a promising therapeutic strategy in liver fibrosis. [ABSTRACT FROM AUTHOR]

Effective vaccines against malaria caused by Plasmodium falciparum are still lacking, and the molecular mechanism of the host-parasite interaction is not fully understood. Here we demonstrate that the interaction of RAP2, a parasite-secreted rhoptry protein that functions in the parasitophorous vacuole formation stage of the invasion, and CD147 on the host erythrocyte is essential for erythrocyte invasion by P falciparum and is independent from all previously identified interactions involved. Importantly, the blockade of the CD147-RAP2 interaction by HP6H8, a humanized CD147 antibody, completely abolished the parasite invasion with both cure and preventative functions in a humanized mouse model. Together with its long half-life on human red blood cells and its safety profile in cynomolgus monkeys, HP6H8 is the first antibody that offers an advantageous approach by targeting a more conserved late-stage parasite ligand for preventing as well as treating severe malaria. [ABSTRACT FROM AUTHOR]

Cluster of differentiation (CD)147 is highly involved in the T cell activation process. High CD147 expression is observed on the surfaces of activated T cells, particularly CD4+ T cells. In organ transplantation, it is important to prevent graft rejection resulting from the excessive activation of T cells, particularly CD4+ T cells, which exhibit a key role in amplifying the immune response. The present study aimed to investigate the effects of CD147 blockade in vitro and in vivo and used a transplant rejection system to assess the feasibility of utilizing CD147 antibody‑based immunosuppressant drugs for the treatment of graft rejection. The effects of CD147 antibodies were evaluated on lymphocyte proliferation stimulated by phytohemagglutinin or CD3/CD28 magnetic beads and in a one‑way mixed lymphocyte reaction (MLR) system in vitro. For the in vivo analysis, an allogeneic skin transplantation mouse model was used. CD147 antibodies were effective against lymphocytes, particularly CD4+T lymphocytes, and were additionally effective in the one‑way MLR system. In the allogeneic skin transplantation mouse model, the survival of transplanted skin was extended in the CD147 antibody‑treated group. Furthermore, the level of inflammatory cell infiltration in transplanted skin was reduced. CD147 blockade decreased the serum levels of interleukin (IL)‑17 and the proportions of peripheral blood CD4+ and CD8+ memory T cells. The data demonstrated that CD147 blockade suppressed skin graft rejection, primarily by suppressing CD4+T and memory T cell proliferation, indicating that CD147 exhibits great potential as a target of immunosuppressant drugs. [ABSTRACT FROM AUTHOR]

The immunoglobulin superfamily member CD147 is a widely expressed glycoprotein that occurs in both a membrane-spanning and soluble form. Sandwich ELISA is a powerful tool for analyzing soluble antigens. The aim of the present study was to obtain a highly specific polyclonal antibody against human CD147 that can be used for sandwich ELISA analysis. Expression of recombinant CD147 by a eukaryotic expression system was used to immunize rabbits to obtain antiserum. A highly specific polyclonal antibody that was able to detect soluble CD147 in sandwich ELISA was obtained by antigen-immunoaffinity chromatography purification. The purity of rabbit anti-CD147 polyclonal antibodies was ~99%, and ELISA analysis was able to determine the titer of the rabbit anti-CD147 polyclonal antibodies at 1:512,000. The lowest concentration of the standard CD147 antigen that the sandwich ELISA was able to detect was 31.25 pg/ml. The sandwich ELISA system was composed of anti-hepatoma HAb18 monoclonal antibodies and purified rabbit anti-CD147 polyclonal antibodies. The present study demonstrated that antigen-immunoaffinity chromatography may be a good technique for the purification of polyclonal antibodies, which may be used to detect antigen in sandwich ELISAs. [ABSTRACT FROM AUTHOR]

Drug resistance remains a major clinical obstacle to successful treatment of cancer. As posttranslational modification is becoming widely recognized to affect the function of oncoproteins, targeting specific posttranslational protein modification provides an attractive strategy for anticancer drug development. CD147 is a transmembrane glycoprotein contributing to chemo-resistance of cancer cells in a variety of human malignancies. Ubiquitination is an important posttranslational modification mediating protein degradation. Degradation of oncoproteins, CD147 included, emerges as an attractive alternative for tumor inhibition. However, the ubiquitination of CD147 remains elusive. Here in this study, we found that deletion of the CD147 intracellular domain (CD147-ICD) prolonged the half-life of CD147 in HEK293T cells, and we identified that CD147-ICD interacts with FBXO22 using mass spectrometry and Western blot. Then, we demonstrated that FBXO22 mediates the polyubiquitination and degradation of CD147 by recognizing CD147-ICD. While knocking down of FBXO22 prolonged the half-life of CD147 in HEK293T cells, we found that FBXO22 regulates CD147 protein turnover in SMMC-7721, Huh-7 and A549 cells. Moreover, we found that the low level of FBXO22 contributes to the accumulation of CD147 and thereafter the cisplatin resistance of A549/DDP cells. To conclude, our study demonstrated that FBXO22 mediated the polyubiquitination and degradation of CD147 by interacting with CD147-ICD, and CD147 polyubiquitination by FBXO22 reversed cisplatin resistance of tumor cells. [ABSTRACT FROM AUTHOR]

The article discusses the role of posttranslational modifications in the development of autoimmune diseases, specifically ankylosing spondylitis. Topics include examines the study identified cysteine carboxyethylation, a PTM induced by the gut metabolite 3-hydroxypropionic acid, as a key factor in the generation of neoantigens that trigger autoimmune responses in AS patients.

Hepatocellular carcinoma (HCC) is currently the third most common cause of cancer-related death in the Asia-Pacific region. Our previous work showed that knockdown of CD98 significantly inhibits malignant HCC cell phenotypes in vitro and in vivo. The level of CD98 in the membrane is tightly regulated to mediate complex processes associated with cell-cell communication and intracellular signaling. In addition, the intracellular domain of CD98 (CD98-ICD) seems to be of vital importance for recycling CD98 to the membrane after it is endocytosed. The intracellular and transmembrane domains of CD98 associate with β-integrins (primarily β1 but also β3), and this association is essential for CD98 mediation of integrin-like signaling and complements dominant suppression of β1-integrin. We speculated that isolated CD98-ICD would similarly suppress β1-integrin activation and inhibit the malignant behaviors of cancer cells. In particular, the exact role of CD98-ICD has not been studied independently in HCC. In this study, we found that ectopic expression of CD98-ICD inhibited the malignant phenotypes of HCC cells, and the mechanism possibly involves β1-integrin suppression. Moreover, the expression levels of CD98, β1-integrin-A (the activated form of β1-integrin) and Ki-67 were significantly increased in HCC tissues relative to those of normal liver tissues. Therefore, our preliminary study indicates that ectopic CD98-ICD has an inhibitory role in the malignant development of HCC, and shows that CD98-ICD acts as a dominant negative mutant of CD98 that attenuates β1-integrin activation. CD98-ICD may emerge as a promising candidate for antitumor treatment. [ABSTRACT FROM AUTHOR]

Background: Oncolytic virus which arms the therapeutic gene to enhance anti-tumor activity is a prevalent strategy to improve oncovirotherapy of cancer. Newcastle disease virus (NDV) is a naturally oncolytic virus used for cancer therapy. Previously, we generated a mouse-human chimeric HAb18 antibody (cHAb18) against tumor-associated antigen CD147 and demonstrated the inhibition of invasion and migration of hepatocellular carcinoma (HCC) cells. Here, we constructed a recombinant NDV carrying intact cHAb18 gene (rNDV-18HL) based on Italien strain using a reverse genetics system. Method: Recombinant rNDV-18HL was generated using reverse genetics technology. The characteristics of virally expressed cHAb18 antibody were identified by western blot, enzyme-linked immunosorbent assay, transwell invasion assay, and surface plasmon resonance technology. The biodistribution of recombinant rNDV-18HL using orthotopic xenograft mouse model was assessed with living imaging and immunohistochemistry. Kaplan-Meier survival curves and the log-rank test were performed to analyze the anti-tumor activity of rNDV-18HL. Results: The cHAb18 was produced in rNDV-18HL-infected cells followed by releasing into the supernatant by cytolysis. The rNDV-18HL-encoded cHAb18 antibody kept affinity for CD147 and showed inhibiting the migration and invasion of HCC cells. Viral replication and virulence were not attenuated by the incorporation of cHAb18 gene which significantly enhanced the suppression of relict tumor cell migration. The rNDV-18HL selectively replicated in orthotopic HCC xenografts leading to cHAb18 expression in situ, which induced the tumor necrosis, reduced the intrahepatic metastasis, and prolonged the survival in mice. Conclusions: This study provides a new strategy of arming oncolytic NDV with therapeutic antibody to enhance anti-tumor efficacy of cancer therapy. [ABSTRACT FROM AUTHOR]

Background: Dysregulated endocytosis of membrane proteins contributes significantly to several hallmarks of cancer. Basigin can enhance cancer progression, but its precise mechanism remains unclear. CD98 promotes cell spreading and tumorigenicity by triggering integrin clustering and enhancing cell adhesion to the extracellular matrix. The endocytosis and recyle of basigin and CD98 might play critical roles in cancer. Methods: The role of CD98 was confirmed in liver cancer cells by cell spreading in vitro and tumorigenicity by nude mice xenograft tumor assay in vivo; membrane expression of basigin and CD98 in SMMC-7721 was measured by FCAS; pull down and SPR analysis were uses to reveal the direct association between basigin and CD98; DsRed1 tagged CD98 was blocked in the cytoplasm in K7721 (whose basigin was knockn out) and had a well colocalization with ER and Rab5a positive recycling endosomes under co-focal; finally, by FRET imaging and FCAS we observed the internalization of basigin and CD98 was flotillin-1-regulated, and their recycle at early steps was Arf6-mediated. Results: Basigin and CD98 were highly expressed and co-localized on the human hepatocellular carcinoma (HCC) cell membrane; basigin can directly bind to CD98, mediating CD98 redistribution on the HCC cell membrane and activating the downstream integrin signaling pathway. Internalization of basigin and CD98 was flotillin-1 regulated the and their recycling was mediated by Arf6. This recycling process for basigin and CD98 promotes cell spreading and tumor growth in liver cancer xenografts. Conclusion: Basigin, as a redistribution chaperone of CD98, plays a critical role in promoting cell spreading and the progression of hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

Background: Itai-itai disease primarily results from cadmium (Cd) exposure and is known as one of the four major pollution diseases in Japan. Cd pollution is more serious in several areas of China than in Japan. However, there is still a lack of information regarding the threshold level of Cd exposure for the adverse health effects in the general Chinese population. This study aims to evaluate the reference value of urinary Cd (UCd) for renal dysfunction in a Chinese population as the benchmark dose lower confidence limit (BMDL) based on a large sample survey. Methods: A total of 6103 participants who lived in five Cd polluted areas of China participated in this study. We analyzed UCd levels as a biomarker of exposure and urinary β2-microglobulin (Uβ2-MG) levels as a renal tubular effect biomarker. The BMD studies were performed using BMD software. The benchmark response (BMR) was defined as a 10 % additional risk above the background. Results: There was a positive correlation between the UCd levels and the prevalence of Uβ2-MG. The BMD of UCd for Uβ2-MG was estimated for each province. The findings showed that the BMD levels were related to the participants' geographic region, which may be partially due to the large differences in Cd exposure level, ethnic group, lifestyle and diet of the sample population in these study areas. The reference level of UCd for the renal effects was further evaluated by combining the five sets of data from all 6103 subjects. The overall BMDLs of UCd for Uβ2-MG with an excess risk of 10 % were 2.00 μg/g creatinine (μg/g cr) in males and 1.69 μg/g cr in females, which were significantly lower than the World Health Organization (WHO) threshold level of 5 μg/g cr for Cd-related renal effects. Conclusions: The selection of the sample population and geographic region affected the BMDL evaluation. Based on the findings of this survey of a large sample population, the UCd BMDLs for Uβ2-MG in males with BMRs at 10 % were 2.00 μg/g cr. The BMD was slightly lower in females, which indicated that females may be relatively more sensitive to Cd exposure than males. [ABSTRACT FROM AUTHOR]

Background: Itai-itai disease primarily results from cadmium (Cd) exposure and is known as one of the four major pollution diseases in Japan. Cd pollution is more serious in several areas of China than in Japan. However, there is still a lack of information regarding the threshold level of Cd exposure for the adverse health effects in the general Chinese population. This study aims to evaluate the reference value of urinary Cd (UCd) for renal dysfunction in a Chinese population as the benchmark dose lower confidence limit (BMDL) based on a large sample survey. Methods: A total of 6103 participants who lived in five Cd polluted areas of China participated in this study. We analyzed UCd levels as a biomarker of exposure and urinary β2-microglobulin (Uβ2-MG) levels as a renal tubular effect biomarker. The BMD studies were performed using BMD software. The benchmark response (BMR) was defined as a 10 % additional risk above the background. Results: There was a positive correlation between the UCd levels and the prevalence of Uβ2-MG. The BMD of UCd for Uβ2-MG was estimated for each province. The findings showed that the BMD levels were related to the participants’ geographic region, which may be partially due to the large differences in Cd exposure level, ethnic group, lifestyle and diet of the sample population in these study areas. The reference level of UCd for the renal effects was further evaluated by combining the five sets of data from all 6103 subjects. The overall BMDLs of UCd for Uβ2-MG with an excess risk of 10 % were 2.00 μg/g creatinine (μg/g cr) in males and 1.69 μg/g cr in females, which were significantly lower than the World Health Organization (WHO) threshold level of 5 μg/g cr for Cd-related renal effects. Conclusions: The selection of the sample population and geographic region affected the BMDL evaluation. Based on the findings of this survey of a large sample population, the UCd BMDLs for Uβ2-MG in males with BMRs at 10 % were 2.00 μg/g cr. The BMD was slightly lower in females, which indicated that females may be relatively more sensitive to Cd exposure than males. [ABSTRACT FROM AUTHOR]

Growing evidence indicates that miR-146a is involved in carcinogenesis and tumor progression in several human malignancies. However, the molecular details underlying miR-146a mediated regulation of its target genes and its precise biological function in cancer, especially in hepatocellular carcinoma (HCC) remains unclear. Methods: The expression levels of genes including miR-146a, APC, VEGF and HAb18G were examined in HCC cell lines and patient specimens were compared with control levels using quantitative reverse transcription-PCR. The functions of miR-146a and HAb18G in migration/invasion and liver metastasis formation were determined by transwell and spleen injection assays, respectively. miR-146a related genes were determined by PCR array. The potential regulatory targets of miR-146a were determined by bioinformatics and prediction tools, correlation with target protein expression, and luciferase reporter assay. DNA methylation status of miR-146a promoter were performed by PCR analysis of bisulfite-modified genomic DNA. Results: We demonstrated that miR-146a expression was markedly downregulated in hepatoma cells and hepatoma tissues compared to immortalized normal liver epithelial cells and normal hepatic tissues. DNA methylation of miR-146a promoter correlated with its downexpression and with liver cancer metastasis. The restoration of miR-146a dramatically suppressed HCC cell invasion and metastasis by repressing VEGF expression through upregulating APC, which inhibits β-catenin accumulation in nucleus, and downregulating NF-κB p65 by targeting HAb18G. In human HCC, miR-146a expression was negative correlated with increased HAb18G, VEGF, NF-κB p65 and beneficial prognosis. Conclusion: This study identified a novel target of miR-146a and defined miR-146a as a crucial tumor suppressor in human HCC that acts through multiple pathways and mechanisms to suppress HCC invasion or metastasis. [ABSTRACT FROM AUTHOR]

Growing evidence indicates that mi-146a is involved in carcinogenesis and tumor progression in several human malignancies. However, the molecular details underlying mi-146a mediated regulation of its target genes and its precise biological function in cancer, especially in hepatocellular carcinoma (HCC) remains unclear. Methods: The expression levels of genes including mi-146a, APC, VEGF and HAb18G were examined in HCC cell lines and patient specimens were compared with control levels using quantitative reverse transcription-PCR. The functions of mi-146a and HAb18G in migration/invasion and liver metastasis formation were determined by transwell and spleen injection assays, respectively. mi-146a related genes were determined by PCR array. The potential regulatory targets of mi-146a were determined by bioinformatics and prediction tools, correlation with target protein expression, and luciferase reporter assay. DNA methylation status of mi-146a promoter were performed by PCR analysis of bisulfite-modified genomic DNA. Results: We demonstrated that mi-146a expression was markedly downregulated in hepatoma cells and hepatoma tissues compared to immortalized normal liver epithelial cells and normal hepatic tissues. DNA methylation of mi-146a promoter correlated with its downexpression and with liver cancer metastasis. The restoration of mi-146a dramatically suppressed HCC cell invasion and metastasis by repressing VEGF expression through upregulating APC, which inhibits β-catenin accumulation in nucleus, and downregulating NF-κB p65 by targeting HAb18G. In human HCC, mi-146a expression was negative correlated with increased HAb18G, VEGF, NF-κB p65 and beneficial prognosis. Conclusion: This study identified a novel target of mi-146a and defined mi-146a as a crucial tumor suppressor in human HCC that acts through multiple pathways and mechanisms to suppress HCC invasion or metastasis. [ABSTRACT FROM AUTHOR]

Growing evidence indicates that miR-146a is involved in carcinogenesis and tumor progression in several human malignancies. However, the molecular details underlying miR- 146a mediated regulation of its target genes and its precise biological function in cancer, especially in hepatocellular carcinoma (HCC) remains unclear. Methods The expression levels of genes including miR-146a, APC, VEGF and HAb18G were examined in HCC cell lines and patient specimens were compared with control levels using quantitative reverse transcription-PCR. The functions of miR-146a and HAb18G in migration/invasion and liver metastasis formation were determined by transwell and spleen injection assays, respectively. miR-146a related genes were determined by PCR array. The potential regulatory targets of miR-146a were determined by bioinformatics and prediction tools, correlation with target protein expression, and luciferase reporter assay. DNA methylation status of miR-146a promoter were performed by PCR analysis of bisulfite-modified genomic DNA. Results We demonstrated that miR-146a expression was markedly downregulated in hepatoma cells and hepatoma tissues compared to immortalized normal liver epithelial cells and normal hepatic tissues. DNA methylation of miR-146a promoter correlated with its downexpression and with liver cancer metastasis. The restoration of miR-146a dramatically suppressed HCC cell invasion and metastasis by repressing VEGF expression through upregulating APC, which inhibits β-catenin accumulation in nucleus, and downregulating NF-κB p65 by targeting HAb18G. In human HCC, miR-146a expression was negative correlated with increased HAb18G, VEGF, NF-κB p65 and beneficial prognosis. Conclusion This study identified a novel target of miR-146a and defined miR-146a as a crucial tumor suppressor in human HCC that acts through multiple pathways and mechanisms to suppress HCC invasion or metastasis. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common cancer in women for which the metastatic process is still poorly understood. CD 147 is upregulated in breast cancer and has been associated with tumor progression, but little is known about its regulatory mechanisms. In this study, we demonstrated that CD147 was overexpressed in breast cancer tissues and cell lines, and the high expression correlated with tumor invasion and metastasis. We also found that the transcription factors Sp1 and c-Myc could bind to the CD147 promoter and enhance its expression. The CD 147 mRNA has a 748-bp 30-untranslated region (UTR) with many miRNA target sites, suggesting possible regulation by miRNAs. We discovered that miR-22 repressed CD 147 expression by directly targeting the CD147 30UTR. We also determined that miR-22 could indirectly participate in CD147 modulation by downregulating Sp1 expression. miR-22 could form an autoregulatory loop with Sp1, which repressed miR-22 transcription by binding to the miR-22 promoter. Together with the c-Myc-mediated inhibition of miR-22 expression, our investigation identified a miR-22/Sp1/c-Myc network that regulates CD147 gene transcription. In addition, miR-22 overexpression suppressed breast cancer cell invasion, metastasis, and proliferation by targeting CD 147 in vitro and in vivo. Furthermore, we found that miR-22 was significantly downregulated in breast cancer tissues and that its expression was inversely correlated with the tumor-node-metastasis stage and lymphatic metastasis in patients. Our study provides the first evidence that an miR-22/Sp1/c-Myc network regulates CD147 upregulation in breast cancer and that miR-22 represses breast cancer invasive and metastatic capacities. [ABSTRACT FROM AUTHOR]

Glycosylation of glycoproteins is one of many molecular changes that accompany malignant transformation. Post-translational modifications of proteins are closely associated with the adhesion, invasion, and metastasis of tumor cells. CD147, a tumor-associated antigen that is highly expressed on the cell surface of various tumors, is a potential target for cancer diagnosis and therapy. A significant biochemical property of CD147 is its high level of glycosylation. Studies on the structure and function of CD147 glycosylation provide valuable clues to the development of targeted therapies for cancer. Here, we review current understanding of the glycosylation characteristics of CD147 and the glycosyltransferases involved in the biosynthesis of CD147 N-glycans. Finally, we discuss proteins regulating CD147 glycosylation and the biological functions of CD147 glycosylation. [ABSTRACT FROM AUTHOR]

Several lines of evidence suggest that HAb18G/CD147 interacts with the integrin variants α3β1 and α6β1. However, the mechanism of the interaction remains largely unknown. In this study, mammalian protein-protein interaction trap (MAPPIT), a mammalian two-hybrid method, was used to study the CD147- integrin β1 subunit interaction. CD147 in human hepatocellular carcinoma (HCC) cells was interfered with by small hairpin RNA. Nude mouse xenograft model and metastatic model of HCC were used to detect the role of CD147 in carcinogenesis and metastasis. We found that the extracellular membraneproximal domain of HAb18G/CD147 (I-type domain) binds at the metal ion-dependent adhesion site in the βA domain of the integrin β1 subunit, and Asp179 in the I-type domain of HAb18G/CD147 plays an important role in the interaction. The levels of the proteins that act downstream of integrin, including focal adhesion kinase (FAK) and phospho-FAK, were decreased, and the cytoskeletal structures of HCC cells were rearranged bearing the HAb18G/CD147 deletion. Simultaneously, the migration and invasion capacities, secretion of matrix metalloproteinases, colony formation rate in vitro, and tumor growth and metastatic potential in vivo were decreased. These results indicate that the interaction of HAb18G/CD147 extracellular I-type domain with the integrin β1 metal ion-dependent adhesion site motif activates the downstream FAK signaling pathway, subsequently enhancing the malignant properties of HCC cells. [ABSTRACT FROM AUTHOR]

RNA-seq is a powerful tool for comprehensive characterization of whole transcriptome at both gene and exon levels and with a unique ability of identifying novel splicing variants. To date, RNA-seq analysis of HBV-related hepatocellular carcinoma (HCC) has not been reported. In this study, we performed transcriptome analyses for 10 matched pairs of cancer and non-cancerous tissues from HCC patients on Solexa/Illumina GAII platform. On average, about 21.6 million sequencing reads and 10.6 million aligned reads were obtained for samples sequenced on each lane, which was able to identify >50% of all the annotated genes for each sample. Furthermore, we identified 1,378 significantly differently expressed genes (DEGs) and 24, 338 differentially expressed exons (DEEs). Comprehensive function analyses indicated that cell growthrelated, metabolism-related and immune-related pathways were most significantly enriched by DEGs, pointing to a complex mechanism for HCC carcinogenesis. Positional gene enrichment analysis showed that DEGs were most significantly enriched at chromosome 8q21.3-24.3. The most interesting findings were from the analysis at exon levels where we characterized three major patterns of expression changes between gene and exon levels, implying a much complex landscape of transcript-specific differential expressions in HCC. Finally, we identified a novel highly up-regulated exon-exon junction in ATAD2 gene in HCC tissues. Overall, to our best knowledge, our study represents the most comprehensive characterization of HBV-related HCC transcriptome including exon level expression changes and novel splicing variants, which illustrated the power of RNA-seq and provided important clues for understanding the molecular mechanisms of HCC pathogenesis at system-wide levels. [ABSTRACT FROM AUTHOR]

Cyclophilin A (CyPA) is a ubiquitously distributed peptidylprolyl cis-trans isomerase (PPIase) that possesses diverse biological functions. Extracellular CyPA is a potent chemokine, which can directly induce leukocyte chemotaxis and contribute to the pathogenesis of inflammation-mediated diseases. Although it has been identified that the chemotaxis activity of CyPA is mediated through its cell surface signaling receptor CD147, the role of CyPA PPIase activity in this process is disputable, and the underlying molecular mechanism is still poorly understood. In this study, we present the first evidence that CyPA induces leukocyte chemotaxis through a direct binding with the ectodomain of CD147 (CD147ECT), independent of its PPIase activity. Although NMR study indicates that the CD147ECT binding site on CyPA overlaps with the PPIase active site, the PPIase inactive mutant CyPAR55A exhibits similar CD147ECT binding ability and chemotaxis activity to those of CyPAWT. Furthermore, we have identified three key residues of CyPA involved in CD147ECT binding and found that mutations H70A, T107A, and R69A result in similar levels of reduction in CD147ECT binding ability and chemotaxis activity for CyPA, without affecting the PPIase activity. Our findings indicate that there exists a novel mechanism for CyPA to regulate cellular signaling processes, shedding new light on its applications in drug development and providing a new targeting site for drug design. [ABSTRACT FROM AUTHOR]

Aberrant expression of CK20 and Ki-67 has been documented in many kinds of primary tumors and has proved useful as an ancillary diagnostic aid for those tumors. The aim of this study was to analyze the expression patterns of CK20 and Ki-67 in human bladder carcinomas (BCa) and to evaluate their clinical significance in the progression of BCa. CK20 and Ki-67 expression in BCa and normal bladder tissues were detected by immunohistochemical staining. The Spearman correlation was calculated between the expression of CK20 and Ki-67 in BCa tissues. The correlation of CK20 and Ki-67 expression with the clinicopathological characteristics and the prognosis of BCa were subsequently assessed. CK20 expression was positively expressed in 103/154 (66.9%) of BCa and 2/30 (6.67%) of normal bladder tissues, respectively. The positive expression rate of Ki-67 in BCa tissues was also significantly higher than those in normal bladder tissues (81.8 vs. 10%, p < 0.01). The Spearman analysis indicated that the expression level of CK20 has a significant positive correlation with that of Ki-67 (rs = 0.86, p = 0.02). Pathologic findings demonstrated that the intensity of CK20 and Ki-67 staining in cancerous tissues was associated significantly with tumor grades ( p = 0.03, p < 0.01), distant metastasis (both p < 0.01) and TNM grades ( p = 0.01, p = 0.03) of BCa. The progression-free survival of the patients with CK20 (+)/Ki-67 (+) expression was poorest ( p < 0.01). The results suggest that the expression of CK20 and Ki-67 may be an important feature of BCa, and the detection of their co-expression may benefit the prediction of BCa prognosis. [ABSTRACT FROM AUTHOR]

Background: Acquisition of resistance to "anoikis" facilitates the survival of cells under independent matrix-deficient conditions, such as cells in tumor progression and the production of suspension culture cells for biomedical engineering. There is evidence suggesting that CD147, an adhesion molecule associated with survival of cells in tumor metastasis and cell-cell contacts, plays an important role in resistance to anoikis. However, information regarding the functions of CD147 in mediating cell-cell contacts and anoikis-resistance remains limited and even self-contradictory. Results: An anoikis-resistant clone (HEK293ar), derived from anoikis-sensitive parental Human Embryonic Kidney 293 cells, survived anoikis by the formation of cell-cell contacts. The expression of HAb18G/CD147 (a member of the CD147 family) was upregulated and the protein was located at cell-cell junctions. Upregulation of HAb18G/CD147 in suspended HEK293ar cells suppressed anoikis by mediating the formation of cell-cell adhesions. Anoikis resistance in HEK293ar cells also required E-cadherin-mediated cell-cell contacts. Knock-down of HAb18G/CD147 and E-cadherin inhibited cell-cell contacts formation and increased anoikis sensitivity respectively. When HAb18G/CD147 was downregulated, E-cadherin expression in HEK293ar cells was significantly suppressed; however, knockdown of Ecadherin by E-cadherin siRNA or blocking of E-cadherin binding activity with a specific antibody and EDTA had no significant effect on HAb18G/CD147 expression. Finally, pretreatment with LY294002, a phosphoinositide 3-kinase (PI3K/AKT) inhibitor, disrupted cell-cell contacts and decreased cell number, but this was not the case in cells treated with the extracellular signal-regulated kinase (ERK) inhibitor PD98059. Conclusions: Our results provide new evidence that HAb18G/CD147-mediated cell-cell contact confers anoikis resistance in an E-cadherin-dependent manner; and cell-cell contact mediated resistance to anoikis implicates PI3K pathway in a highly relevant cell model (HEK293ar). Understanding of the role of HAb18G/CD147 cell-cell contacts in anoikis resistance may help in understanding the survival of cells in anchorage-independent growth, such as cells in tumor metastasis and suspension culture produced for biomedical engineering. Our results also contribute to a better understanding of the biology of HEK293 cell spheroids, a major workhorse for producing human therapeutic agents and viral vaccines. [ABSTRACT FROM AUTHOR]

Previous studies show that cyclophilin A (CypA) acts as a strong chemotactic cytokine to neutrophils, eosinophils, and monocytes in rheumatoid arthritis (RA). In this study, monocytes were stimulated by purified CypA and the production of matrix metalloproteinase (MMPs), the cell invasion and the release of inflammatory cytokines were detected respectively by gelatin zymography, invasion assay, and cytometric bead array FCM. The elevated level of inflammatory cytokine IL-8 was also detected. Results showed that CypA significantly promoted the invasion of THP-1 cells and increased the production of MMP-2 and MMP-9, which displayed a biphasic concentration dependency. In vivo experiments found that the cartilage erosion scores in CypA injection group were significantly higher than those in control group ( P < 0.05). Our findings suggest that CypA significantly enhances the secretion of MMP-2 and MMP-9, the cell invasion, and the inflammatory cytokines production of monocytes. Our findings may shed some new light on the inflammatory process and the degradation of cartilage and bone in RA. [ABSTRACT FROM AUTHOR]

Aims: To evaluate HAb18G/CD147 as a cancer-associated biomarker using its monoclonal antibody HAb18. Methods and results: On immunohistochemical analysis of 28 tissue microarrays and pathological sections of 1117 breast tissue samples, HAb18G/CD147 was expressed in carcinoma with an overall positivity rate of 67.76%, which was significantly higher than that in sarcomas (27.34%, P < 0.0001) and normal epithelial (5.18%, P < 0.0001) and fetal (2.67%, P < 0.0001) tissues. In epithelial tissues from 14 organs, the difference in HAb18G/CD147 expression between normal epithelium and the corresponding carcinoma was also significant ( P < 0.05 for each pair). This expression in carcinoma was also found at the mRNA level, suggesting transcriptional level regulation of HAb18G/CD147 expression. In a retrospective study of 106 patients with infiltrating ductal carcinoma of the breast, the level of HAb18G/CD147 expression was positively correlated with tumour recurrence/metastasis ( P = 0.0003) and negatively correlated with survival of breast cancer patients ( P = 0.002). Multivariable Cox regression analysis showed that HAb18G/CD147 was an independent prognostic factor. Conclusions: HAb18G/CD147 is significantly expressed in various cancers and appears to have prognostic significance, rendering it a possible cancer-associated biomarker for pathological diagnosis, prognostic evaluation, targeted therapy and radioimmunoimaging of a broad range of cancer types. [ABSTRACT FROM AUTHOR]

Background/Aims: Activated hepatic stellate cells (HSCs) are the crucial factor responsible for liver fibrosis and involved in development of hepatocellular carcinoma (HCC) by interaction with tumour cells. Newcastle disease virus (NDV) has the oncolytic characteristics of intrinsically selective replication in neoplasia cells and transformed cells. But, NDV replication in HSCs and effects on hepatic fibrosis have not been reported. Methods: We detected the effect of conditioned medium (CM) from human HCC cells on the activation of human HSC line, LX-2 by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and reverse transcriptase-polymerase chain reaction (RT-PCR). The replication of NDV was evaluated in LX-2 cells and primary-cultured mouse HSCs by flow cytometry or by a fluorescence microscope. Indices for hepatic fibrosis were determined in HSCs and a hepatic fibrosis mouse model by gelatin zymography, RT-PCR, Western blot and Sirius red staining after NDV infection. Colocalization of NDV virions and α-smooth muscle actin (α-SMA) were detected by double immunofluorescence staining. Detection of apoptosis was carried out in liver tissues of NDV-treated mice by the TdT-mediated dUTP nick-end labelling assay. Results: Tumour-CM and transforming growth factor-β1 (TGF-β1) could promote the proliferation and activation of LX-2 cells, indicated by the enhanced expression of α-SMA, collagen I, tissue inhibitor of metalloproteinase (TIMP)-1 and TGF-β1. Activated HSCs facilitated the replication of NDV, thereby repressing the secretion of MMP, the expression of these indices for hepatic fibrosis and the expression of α-SMA and collagen fibrils in hepatic fibrosis of the mouse induced by carbon tetrachloride. Conclusions: HCC cells promote the activation of HSCs and NDV attenuates the activation and represses the hepatic fibrosis by selective replication in activated HSCs. [ABSTRACT FROM AUTHOR]

Aim: CD147 and MMPs have been demonstrated to be involved in tumor invasion and angiogenesis. The aim of this study was to analyze the clinicopathological significance of CD147, MMP-1, MMP-2 and MMP-9 expression in human prostate cancer (PCa) and to evaluate their involvement in the progression of PCa. Methods: CD147, MMP-1, MMP-2 and MMP-9 expression was assessed in paraffin-embedded specimens collected from 62 cases of PCa and 15 cases of benign prostatic hyperplasia (BPH) by immunohistochemistry. Spearman’s correlation was applied to determine possible relationships between CD147, MMP-1, MMP-2 and MMP-9 expression and PCa. The association of CD147 and MMP-2 protein expression with the clinicopathological characteristics and the prognosis of PCa was subsequently assessed. Results: CD147was expressed in 51/62 (82.3%) PCa patients and in 2/15 (13.3%) BPH cases. MMP-1, MMP-2 and MMP-9 expression was significantly higher in PCa tissue than in BPH tissue. Using Spearman analysis, a significant positive correlation between CD147 and MMP-1, MMP-2 and MMP-9 expression was found (p <0.05). CD147 and MMP-2 expression was correlated with TMN grade and Gleason score. Patients with concurrent expression of CD147+ and MMP-2+ had the lowest survival (p <0.01). Conclusion: The results suggest that concurrent expression of CD147 and MMP may be an important characteristic of PCa which may help in the prediction of PCa progression. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

CD 147, a member of the immunoglobulin superfamily (IgSF), plays fundamental roles in intercellular interactions in numerous pathological and physiological processes. Importantly, our previous studies have demonstrated that HAb18G/CD147 is a novel hepatocellular carcinoma (HCC) -associated antigen, and HAb18G/CD147 stimulates adjacent fibroblasts and HCC cells to produce elevated levels of several matrix metalloproteinases, facilitating invasion and metastasis of HCC cells. In addition, HAb18G/CD147 has also been shown to be a novel universal cancer biomarker for diagnosis and prognostic assessment of a wide range of cancers, However, the structural basis underlying the multifunctional character of CD147 remains unresolved. We report here the crystal structure of the extracellular portion of HAb18G/CD147 at 2.8 Å resolution. The structure comprises an N-terminal IgC2 domain and a C-terminal lgI domain, which are connected by a 5-residue flexible linker. This unique C2-L domain organization is distinct from those of other IgSF members. Four homophilic dimers exist in the crystal and adopt C2-C2 and C2-I dimerization rather than V-V dimerization commonly found in other IgSF members. This type of homophilic association thus presents a novel model for homophilic interaction between C2 domains of IgSF members. Moreover, the crystal structure of HAb18G/CD147 provides a good structural explanation for the established multifunction of CD147 mediated by homo/heterooligomerizations and should represent a general architecture of other CD 147 family members. [ABSTRACT FROM AUTHOR]

A new chimeric IgG1 antibody hCAb which could be specifically directed against a cell surface-associated glycoprotein of colorectal cancer cells was prepared by genetic engineering technology in our lab. In this study, we explored the potential therapeutic mechanisms and described the evaluation of hCAb directed against colorectal cancer. The standard 51Cr release assay showed that like many other clinically validated IgG1 monoclonal antibodies, hCAb primarily acts by antibody-dependent cell-mediated cytotoxicity (ADCC). The maximal cell lysis of ADCC induced by hCAb was over 50% in the presence of peripheral blood mononuclear cells (PBMCs). Moreover, in viva studies showed potent antitumor effects in nude mice with SW480 and Hce-8693 tumor xenografts. The treatment with hCAb induced a dramatic reduction (over 70%) in tumor volume in comparison to untreated control group. Furthermore, during the period of treatment, the animals treated by hCAb did not show signs of wasting or other visible signs of toxicity. No obvious tissue damage in vital organs was detected. The chimeric antibody hCAb may be a promising candidate in the treatment of human colorectal cancer. This study can provide a reference for the potential application of hCAb in clinical trial. [ABSTRACT FROM AUTHOR]

HAb18G/CD147, a membrane spanning molecule and highly expressed in hepatocellular carcinoma (HCC)cells, was shown to stimulate the production of matrix metalloproteinases (MMPs) in the interaction of tumorcells and fibroblasts. Studies on the EMMPRIN/CD147 showed that CD147 extracellular domain is involvedin the induction of MMPs. To study the biological molecular function of HAb18G/CD147 extracellulardomain (HAb18G/CD147-ED) on production of MMPs following mediated tumor cell invasion, we isolatedfour novel monoclonal anibodies (MAbs)–1B3, 3B3, HAb18Gedomab1, and HAb18Gedomab2—againstHAb18G/CD147-ED by immunization of BALB/c mice with purified HAb18G/CD147-ED fragments, whichwere efficiently expressed in Escherichia coli. Gelatin zymography and Boyden chamber assays were used to identify the production of MMPs in the co-cultured human fibroblast and HCC cells, and to quantify themigrated cells in the presence of the generated MAbs. The results showed that two MAbs (1B3 and 3B3)inhibited the secretion of MMP-2 and the HCC cell invasion, whereas the other two MAbs (HAb18Gedomab1and HAb18Gedomab2) had a reverse function. FCM additive assay showed that four MAbs recognized differentepitopes of HAb18G/CD147-ED. Taken together, the results suggest that various regions ofHAb18G/CD147-ED participated in the regulation of MMP secretion. [ABSTRACT FROM AUTHOR]

Background: During infection and inflammation, circulating blood monocytes migrate from the intravascular compartments to the extravascular compartments, where they mature into tissue macrophages. The maturation process prepares the cells to actively participate in the inflammatory and immune responses, and many factors have been reported to be involved in the process. We found in our study that CD147 played a very important role in this process. Results: By using PMA-differentiated human monocyte cells line THP-1, we found that CD147 mediated matrix metalloproteinases (MMPs) expression of the leukemic THP-1 cells and thus enhanced the invasiveness of THP-1 cells. After 24 hours of PMA-induced monocyte differentiation, the mean fluorescence intensity of CD147 in differentiated THP-1 cells (289.61 ± 31.63) was higher than that of the undifferentiated THP-1 cells (205.1 ± 19.25). There was a significant increase of the levels of proMMP-2, proMMP-9 and their activated forms in the differentiated THP-1 cells. Invasion assays using reconstituted basement membrane showed a good correlation between the invasiveness of THP-1 cells and the production of MMP-2 and MMP-9. The difference in the MMPs expression and the invasive ability was significantly blocked by HAb18G/CD147 antagonistic peptide AP-9. The inhibitory rate of the secretion of proMMP-9 in the undifferentiated THP-1 cells was 45.07%. The inhibitory rate of the secretion of proMMP-9, the activated MMP-9 and proMMP-2 in the differentiated THP-1 cells was 52.90%, 53.79% and 47.80%, respectively. The inhibitory rate of invasive potential in the undifferentiated cells and the differentiated THP-1 cells was 41.82 % and 25.15%, respectively. Conclusion: The results suggest that the expression of CD147 is upregulated during the differentiation of monocyte THP-1 cells to macrophage cells, and CD147 induces the secretion and activation of MMP-2 and MMP-9 and enhances the invasive ability of THP-1 cells. The matured monocytes / macrophages, via their high expression of CD147, may play an important role in promoting the tissue repair or tissue damage during their inflammatory response. [ABSTRACT FROM AUTHOR]

The article discusses a study which characterized the basigin isoforms and the function of basigin-3 to inhibit hepatocellular carcinoma proliferation and invasion.