Huijie Bian

A randomized controlled trial of Licartin for preventing hepatoma recurrence after liver transplantation.

Orthotopic liver transplantation (OLT) is the only curative therapy of HCC with underlying cirrhosis, but due to HCC metastasis and recurrence, its benefit is limited to a small population who meet the strict selection criteria. We previously reported that Licartin ([131I]mAb HAb18G/CD147) was safe and effective in treating HCC patients, and its antigen, HAb18G/CD147, was closely related to HCC invasion and metastasis. Here, we reported a randomized controlled trial to assess the post‐OLT antirecurrence efficacy of Licartin in advanced HCC patients. We randomized 60 post‐OLT patients with HCC, who were at tumor stage 3/4 and outside the Milan criteria before OLT, into 2 groups. Three weeks after OLT, the treatment group received 15.4 MBq/kg of Licartin, while the control group received placebo intravenously for 3 times with an interval of 28 days. At 1‐year follow‐up, the recurrence rate significantly decreased by 30.4% (P = 0.0174) and the survival rate increased by 20.6% (P = 0.0289) in the treatment group, compared with those in the control group. For the control group versus the treatment group, the hazard ratio for recurrence was 3.60 (95% confidence interval [CI], 1.50‐8.60) and that for death was 3.87 (95% CI, 1.23–12.21). Licartin treatment also resulted in an earlier decreased AFP level and a longer time of normal AFP level than placebo (P = 0.0016). No Licartin‐related toxic effects were observed. Conclusion: Licartin is a promising drug for preventing post‐OLT tumor recurrence in advanced HCC patients excluded by the currently strict criteria for OLT. HAb18G/CD147 can be a good drug target. (HEPATOLOGY 2007;45:269–276.)

Promoter hypomethylation up‐regulates CD147 expression through increasing Sp1 binding and associates with poor prognosis in human hepatocellular carcinoma

CD147 is a transmembrane glycoprotein overexpressed in human hepatocellular carcinoma (HCC) which could promote HCC progression and metastasis. Promoter methylation is one of the most important processes in gene regulation. In this study, we aim to investigate CD147 promoter methylation status and the correlation with clinicopathological features and prognosis in HCC. CD147 promoter methylation statuses and expression levels in normal and HCC cell lines and 54 paired HCC and adjacent non‐tumour (ANT) tissues were, respectively, examined by bisulphite genomic sequencing, methylation‐specific PCR, real‐time RT‐PCR, Western blot and immunohistochemistry. The correlations of promoter methylation statuses with CD147 expression level and the clinicopathological features were statistically analysed in HCC patients. Significantly higher expression of CD147 and significantly lower promoter methylation level were observed in HCC cell lines compared to normal cell lines and tissues control. In vivo and in vitro analysis indicated that demethylation with 5‐Aza‐2′‐deoxycytidine led to increased CD147 expression through enhancing Sp1 binding affinity, and methylation with methyltransferase reduced CD147 transcriptional activity through interfering Sp1 binding. CD147 promoter methylation level in HCC tissues (22.22%) was lower than that in ANT tissues (46.30%; P < 0.05). Within HCC tissues, a significant inverse correlation was observed between CD147 expression and methylation level (r=−0.615). Moreover, HCC patients with unmethylated CD147 promoter had a significantly higher recurrence rate (88.1%versus 58.3%; P < 0.05) and death rate (83.3%versus 50.0%; P < 0.05) than patients with methylated CD147 promoter. In conclusions, promoter hypomethylation up‐regulates CD147 expression primarily through increasing Sp1 binding and associates with poor prognosis in HCC patients.

HAb18G/CD147 promotes activation of hepatic stellate cells and is a target for antibody therapy of liver fibrosis

BACKGROUND & AIMS Activated hepatic stellate cells (HSCs) located in the Disses space play a crucial role in liver fibrosis. HAb18G/CD147, a tumor-related glycoprotein, is highly expressed in hepatocellular carcinoma cells and fibroblasts. Whether HAb18G/CD147 plays an important role in the hepatic fibrogenesis is unknown. METHODS Immunohistochemistry for HAb18G/CD147 and α-smooth muscle actin expression in diseased liver tissues was used for correlation analysis. The function of HAb18G/CD147 in fibrogenesis was evaluated with the human HSCs LX-2 cell line and carbon tetrachloride-induced mouse liver fibrosis model. The specific antibody HAb18 targeting HAb18G/CD147 was injected intravenously into the mouse to investigate whether HAb18G/CD147 could be a potential target for liver fibrosis treatment. RESULTS HAb18G/CD147 is highly expressed on activated HSCs in the sinusoid. The positive rates of HAb18G/CD147 expression in human HBV-related liver cirrhosis, liver biopsy with HBV and liver adjacent to hemangioma were 95.6% (65/68), 14.8% (8/54) and 6.4% (8/125), respectively. HAb18G/CD147 expression was significantly correlated with the Child-Pugh grade (r=0.2848, p=0.0186) and with the expression of α-smooth muscle actin in HSCs (r=0.4434, p=0.0002) in liver cirrhosis. Transforming growth factor-β1 upregulated HAb18G/CD147 expression in LX-2 cells. Transfection of HAb18G/CD147 promoted the profibrogenic genes expression. In mouse liver fibrosis model, HAb18G/CD147 expression increased with the development of fibrogenesis and decreased during the liver fibrosis spontaneous recovery. The HAb18 targeting HAb18G/CD147 could attenuate liver fibrosis. CONCLUSIONS These data suggest that HAb18G/CD147 plays a role in HSC activation and is a potential therapeutic target in fibrosis/cirrhosis.

Biodistribution and localization of iodine-131-labeled metuximab in patients with hepatocellular carcinoma.

PURPOSE: Radioimmunotherapy may improve the outcome of hepatocellular carcinoma(HCC) patients by delivering targeted radiation to liver lesion tissue while relatively sparing nontarget tissues. This study was designed to observe the biodistribution, localization and imaging characteristics of 131I -labeled Metuximab in 24 patients with HCC to determine the diagnositic and therapeutic potential of this antibody. METHODS: 24 HCC patients were randomly divided into three groups to receive 18.5, 27.75 and 37 MBq/kg of 131I-labeled Metuximab per kilogram of body weight, respectively. 99mTc-sodium phytate was administered intravenously and the single photon emission computed tomography ?SPECT) scanning was performed. After 48 h, Iodine-131 labeled Metuximab was injected by hepatic artery intubation, and SPECT scan performed at 7d. The percentage of absorbed 131I (?ID) and the time-dependent 131I tumor:non-tumor tissue (T/NT) ratios were calculated at 12, 48, 96 and 192h after injection. RESULTS: The positive Imaging result of MAb scanning in 24 patients showed that the iodine 131 conjugated to Metuximab was apparently accumulated more in hepatoma. Biodistribution studies of 131I-Metuximab in trial I demonstrated that the comparable %ID uptake in tumor (with a T/NT ratio at 12, 48, 96 and 192h) to that in such normal organs, as thyroid, heart, lung, spleen and intestines were all more than 1. The optimal imaging time for the highest T/NT ratio in liver was at 192h. CONCLUSION: 131I-labeled Metuximab could delivere relatively selective radiation to tumor tissues and may have potential efficacy in relieving hepatocellular carcinoma.

Activation of TGF-β1-CD147 positive feedback loop in hepatic stellate cells promotes liver fibrosis

Activation of hepatic stellate cells (HSCs) by transforming growth factor-β1 (TGF-β1) initiates HBV-associated fibrogenesis. The mechanism of TGF-β1 modulating HSC activation is not fully uncovered. We hypothesized a positive feedback signaling loop of TGF-β1-CD147 promoting liver fibrogenesis by activation of HSCs. Human HSC cell line LX-2 and spontaneous liver fibrosis model derived from HBV transgenic mice were used to evaluate the activation of molecules in the signaling loop. Wound healing and cell contraction assay were performed to detect the CD147-overexpressed HSC migration and contraction. The transcriptional regulation of CD147 by TGF-β1/Smad4 was determined using dual-luciferase reporter assay and chromatin immunoprecipitation. We found that a positive reciprocal regulation between TGF-β1 and CD147 mediated HSC activation. CD147 over-expression promoted HSC migration and accelerated TGF-β1-induced cell contraction. Phosphorylation of Smad2 and Smad3 in cooperation with Smad4 mediated the TGF-β1-regulated CD147 expression. Smad4 activated the transcription by direct interaction with CD147 promoter. Meanwhile, CD147 modulated the activated phenotype of HSCs through the ERK1/2 and Sp1 which up-regulated α-SMA, collagen I, and TGF-β1 synthesis. These findings indicate that TGF-β1-CD147 loop plays a key role in regulating the HSC activation and combination of TGF-β receptor inhibitor and anti-CD147 antibody might be promised to reverse fibrogenesis.

Involvement of HAb18G/CD147 in T cell activation and immunological synapse formation

HAb18G/CD147, a glycoprotein of the immunoglobulin super‐family (IgSF), is a T cell activation‐associated molecule. In this report, we demonstrated that HAb18G/CD147 expression on both activated CD4+ and CD8+ T cells was up‐regulated. In vitro cross‐linking of T cells with an anti‐HAb18G/CD147 monoclonal antibody (mAb) 5A12 inhibited T cells proliferation upon T cell receptor stimulation. Such co‐stimulation inhibited T cell proliferation by down‐regulating the expression of CD25 and interleukin‐2 (IL‐2), decreased production of IL‐4 but not interferon‐γ. Laser confocal imaging analysis indicated that HAb18G/CD147 was recruited to the immunological synapse (IS) during T cell activation; triggering HAb18G/CD147 on activated T cells by anti‐HAb18G/CD147 mAb 5A12 strongly dispersed the formation of the IS. Further functional studies showed that the ligation of HAb18G/CD147 with mAb 5A12 decreased the tyrosine phosphorylation and intracellular calcium mobilization levels of T cells. Through docking antibody–antigen interactions, we demonstrated that the function of mAb 5A12 is tightly dependent on its specificity of binding to N‐terminal domain I, which plays pivotal role in the oligomerization of HAb18G/CD147. Taken together, we provide evidence that HAb18G/CD147 could act as a co‐stimulatory receptor to negatively regulate T cell activation and is functionally linked to the formation of the IS.

Randomized Trial of [131I] Metuximab in Treatment of Hepatocellular Carcinoma After Percutaneous Radiofrequency Ablation

To assess the efficacy of combining radioimmunoconjugate [(131)I] metuximab with radiofrequency ablation (RFA) in hepatocellular carcinoma (HCC) treatment compared with RFA alone, a single-center randomized controlled trial was conducted on 127 patients with Barcelona Clinic Liver Cancer staging system (BCLC) classifications of 0-B stage. Patients received either RFA followed by [(131)I] metuximab (n = 62) or RFA alone (n = 65). The primary outcome was overall tumor recurrence. Statistical tests were two-sided. The one- and two-year recurrence rates in the combination group were 31.8% and 58.5%, whereas those in the RFA group were 56.3% and 70.9%, respectively. The median time to overall tumor recurrence was 17 months in the combination group and 10 months in the RFA group (P = .03). The RFA-[(131)I] metuximab treatment showed a greater antirecurrence benefit than RFA in the metuximab target (ie, CD147)-positive subpopulation (P = .007). [(131)I] metuximab may yield prevention of tumor recurrence after RFA.

HAb18G/CD147 is involved in TGF-β-induced epithelial-mesenchymal transition and hepatocellular carcinoma invasion

Epithelial‐mesenchymal transition (EMT) induced by the transforming growth factor beta (TGF‐β) is involved in hepatocarcinogenesis and hepatocellular carcinoma (HCC) metastasis. HAb18G/CD147, a member of the immunoglobulin family, plays an important role in tumor invasion and metastasis. HAb18G/CD147 promotes EMT of hepatocytes through TGF‐β signaling and is transcriptionally regulated by Slug. We investigated the role of HAb18G/CD147 in TGF‐β‐induced EMT in HCC invasion. Two human HCC cell lines, SMMC‐7721 and HepG2, were used to determine the role of HAb18G/CD147 in EMT. Upregulation of HAb18G/CD147 induced by the high doses of TGF‐β1 in SMMC‐7721 (5 ng/mL) and HepG2 cells (10 ng/mL) (P < 0.05). CD147 upregulation was coupled with upregulation of Snail1 and Slug. CD147 knockout significantly decreased the expression of N‐cadherin and vimentin, and colony formation ability of SMMC‐7721 cells. TGF‐β1 enhanced the migration capacity of SMMC‐7721 cells, which was markedly attenuated by CD147 knockdown. Thus, HAb18G/CD147 is involved in TGF‐β‐induced EMT and HCC invasion.

Full-length soluble CD147 promotes MMP-2 expression and is a potential serological marker in detection of hepatocellular carcinoma

BackgroundAs a surface glycoprotein, CD147 is capable of stimulating the production of matrix metalloproteinases (MMPs) from neighboring fibroblasts. The aim of the present study is to explore the role of soluble CD147 on MMPs secretion from hepatocellular carcinoma (HCC) cells, and to investigate the diagnostic value of serum soluble CD147 in the HCC detection.MethodsWe identified the form of soluble CD147 in cell culture supernate of HCC cells and serum of patients with HCC, and explored the role of soluble CD147 on MMPs secretion. Serum CD147 levels were detected by the enzyme-linked immunosorbent assay, and the value of soluble CD147 as a marker in HCC detection was analyzed.ResultsFull length soluble CD147 was presented in the culture medium of HCC cells and serum of patients with HCC. The extracellular domain of soluble CD147 promoted the expression of CD147 and MMP-2 from HCC cells. Knockdown of CD147 markedly diminished the up-regulation of CD147 and MMP-2 which induced by soluble CD147. Soluble CD147 activated ERK, FAK, and PI3K/Akt pathways, leading to the up-regulation of MMP-2. The level of soluble CD147 in serum of patients with HCC was significantly elevated compared with healthy individuals (P < 0.001). Soluble CD147 levels were found to be associated with HCC tumor size (P = 0.007) and Child-Pugh grade (P = 0.007). Moreover, soluble CD147 showed a better performance in distinguishing HCC compared with alpha-fetoprotein.ConclusionsThe extracellular domain of soluble CD147 enhances the secretion of MMP-2 from HCC cells, requiring the cooperation of membrane CD147 and activation of ERK, FAK, and PI3K/Akt signaling. The measurement of soluble CD147 may offer a useful approach in diagnosis of HCC.

Construction of Recombinant Newcastle Disease Virus Italien Strain for Oncolytic Virotherapy of Tumors

Newcastle disease virus (NDV) is a naturally oncolytic virus that has been shown to be safe and effective for cancer therapy. Tumor virotherapy using NDV emerged in the 1950s and has advanced more recently by the increased availability of reverse genetics technology. In this study, we constructed a reverse genetics system based on the virulent and oncolytic NDV Italien strain, and generated two recombinant NDVs carrying a gene encoding either enhanced green fluorescent protein or firefly luciferase. We evaluated the replication and antitumor characteristics of these viruses in vitro and in vivo. Our data showed that the insertion of exogenous reporter genes did not affect NDV replication and sensitivity to type I interferon. The recombinant NDVs kept the property of tumor-selective replication both in vitro and in vivo and strongly induced syncytium formation leading to cell death. Moreover, the recombinant NDVs significantly prolonged the survival of tumor-bearing athymic mice (p=0.017) and suppressed the loss of body weight after intratumoral injection. Taken together, our study provides a novel platform to develop recombinant oncolytic viruses based on the NDV Italien strain and shows the efficiency of recombinant NDV Italien for oncolytic virotherapy of tumors.