Annexin A2 promotes the migration and invasion of human hepatocellular carcinoma cells in vitro by regulating the shedding of CD147-harboring microvesicles from tumor cells.

It has been reported that Annexin A2 (ANXA2) is up-regulated in hepatocellular carcinoma (HCC), but the roles of ANXA2 in the migration and invasion of HCC cells have not been determined. In this study, we found that ANXA2-specific siRNA (si-ANXA2) significantly inhibited the migration and invasion of HCC cells co-cultured with fibroblasts in vitro. In addition, the production of MMP-2 by fibroblasts cultured in supernatant collected from si-ANXA2-transfected HCC cells was notably down-regulated. ANXA2 was also found to be co-localized and co-immunoprecipitated with CD147. Further investigation revealed that the expression of ANXA2 in HCC cells affected the shedding of CD147-harboring membrane microvesicles, acting as a vehicle for CD147 in tumor-stromal interactions and thereby regulating the production of MMP-2 by fibroblasts. Together, these results suggest that ANXA2 enhances the migration and invasion potential of HCC cells in vitro by regulating the trafficking of CD147-harboring membrane microvesicles.

Tolerance induction by exosomes from immature dendritic cells and rapamycin in a mouse cardiac allograft model.

BACKGROUND: Dendritic cells (DCs) release bioactive exosomes that play an important role in immune regulation. Because they express low levels of class I major histocompatibility complex (MHC) and co-stimulatory molecules, exosomes derived from donor immature DCs (imDex) prolong allograft survival by inhibiting T-cell activation. However, this effect is limited and does not induce immunological tolerance when imDex are administered alone. Thus, we tested the effect of combined treatment with donor imDex and low-dose rapamycin on inducing tolerance in a mouse cardiac transplantation model. METHODS: ImDex were obtained from the culture supernatant of immature DCs derived from donor mouse (C57BL/6) bone marrow and were injected with suboptimal doses of rapamycin into recipient mouse (BALB/c) before and after transplantation. The capacity of this treatment to induce immune tolerance was analyzed in vitro and in vivo using the mouse cardiac transplantation model. RESULTS: Donor imDex expressed moderate levels of MHC class II and low levels of MHC class I and co-stimulatory molecules, but neither imDex nor subtherapeutic rapamycin dose alone induced cardiac allograft tolerance. Combined treatment with imDex and rapamycin, however, led to donor specific cardiac allograft tolerance. This effect was accompanied by decreased anti-donor antigen cellular response and an increased percentage of spleen CD4(+)CD25(+) T cells in recipients. Furthermore, this donor specific tolerance could be further transferred to naïve allograft recipients through injection of splenocytes, but not serum, from tolerant recipients. CONCLUSION: Combined with immunosuppressive treatment, donor imDex can prolong cardiac allograft survival and induce donor specific allograft tolerance.

Intravenous injection of mesenchymal stem cells is effective in treating liver fibrosis.

AIM: To compare the influence of different transplant sites in bone marrow mesenchymal stem cell (MSC)-based therapy for liver fibrosis. METHODS: MSCs isolated from Sprague Dawley (SD) rats were induced into hepatocyte-like cells. Liver fibrosis in SD rats was induced with carbon tetrachloride. Following hepatocyte induction in vitro, 4',6-diamidino-2-phenylindole (DAPI)-labeled MSCs were transplanted by intravenous, intrahepatic, and intraperitoneal injection. Histopathological staining, immunohistochemistry, and biochemical analysis were used to compare the morphological and functional liver regeneration among different MSC injection modalities. The expression differences of interleukins, growth factor, extracellular matrix, matrix metalloproteinases, and tissue inhibitor of metalloproteinase were examined by real-time reverse transcription-polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay (ELISA). RESULTS: Four days after exposure to hepatocyte differentiation medium, MSCs that did not express hepatocyte markers could express α-fetoprotein, albumin, and cytokeratin 18. The results of histopathological staining, immunohistochemistry, and biochemical analysis indicated that intravenous injection is more effective at rescuing liver failure than other injection modalities. DAPI-labeled cells were found around liver lobules in all three injection site groups, but the intravenous group had the highest number of cells. PCR and ELISA analysis indicated that interleukin-10 (IL-10) was highest in the intravenous group, whereas il1ß, il6, tnfα and tgfß, which can be regulated by IL10 and are promoters of liver fibrosis, were significantly lower than in the other groups. CONCLUSION: MSC administration is able to protect against liver fibrosis. Intravenous injection is the most favorable treatment modality through promotion of IL10 expression.

Spinal astrocytic activation contributes to mechanical allodynia in a mouse model of type 2 diabetes.

Diabetic neuropathic pain (DNP) plays a major role in decreased life quality of type 2 diabetes patients, however, the molecular mechanisms underlying DNP remain unclear. Emerging research implicates the participation of spinal glial cells in some neuropathic pain models. However, it remains unknown whether spinal glial cells are activated under type 2 diabetic conditions and whether they contribute to diabetes-induced neuropathic pain. In the present study, using a db/db type 2 diabetes mouse model that displayed obvious mechanical allodynia, we found that spinal astrocyte but not microglia was dramatically activated. The mechanical allodynia was significantly attenuated by intrathecally administrated l-α-aminoadipate (astrocytic specific inhibitor) whereas minocycline (microglial specific inhibitor) did not have any effect on mechanical allodynia, which indicated that spinal astrocytic activation contributed to allodynia in db/db mice. Further study aimed to identify the detailed mechanism of astrocyte-induced allodynia in db/db mice. Results showed that spinal activated astrocytes dramatically increased interleukin (IL)-1ß expression which may induce N-methyl-D-aspartic acid receptor (NMDAR) phosphorylation in spinal dorsal horn neurons to enhance pain transmission. Together, these results suggest that spinal activated astrocytes may be a crucial component of mechanical allodynia in type 2 diabetes and "Astrocyte-IL-1ß-NMDAR-Neuron" pathway may be the detailed mechanism of astrocyte-induced allodynia. Thus, inhibiting astrocytic activation in the spinal dorsal horn may represent a novel therapeutic strategy for treating DNP.

Dendritic cells fused with allogeneic hepatocellular carcinoma cell line compared with fused autologous tumor cells as hepatocellular carcinoma vaccines.

PURPOSE: To investigate the specific antitumor responses against autologous hepatocellular carcinoma (HCC) cells of dendritic cells (DCs) fused with allogeneic HCC cell line, and evaluated the feasibility of BEL7402 as an alternative strategy to deliver shared HCC antigens to DCs. METHODS: Previous studies demonstrated fusions of patient-derived DCs and autologous tumor cells could induce T-cell responses against autologous tumors. These fusion cells require patient-derived tumor cells, which are not, however, always available. Here, we report the fusing of autologous DCs with allogeneic HCC cell line to induced cytotoxic T-lymphocyte (CTL) response against autologous HCC cells compare with autologous tumor cells. RESULTS: These DC/ BEL7402 fusion cells co-expressed tumor-associated antigens and DC-derived costimulatory and major histocompatibility complex molecules. Both CD4+ and CD8 T+ cells were activated by the fusion cells as demonstrated by the proliferation of T-cells, the production of cytokines and the simultaneous induction of specific CTL responses. Significantly, CTL induced by dendritic cell/allogeneic BEL7402 fusion cells were able to kill autologous HCC cells by human leukocyte antigen-A2 restricted mechanisms. The results did not show significant difference between DC fusion with autologous hepatocellular carcinoma cells and DC fusion with allogeneic hepatocellular carcinoma cell line. CONCLUSIONS: The fusion of allogeneic HCC cell line and autologous DCs may have applications in antitumor immunotherapy through cross-priming against shared tumor antigens and may provide a platform for adoptive immunotherapy.

Characterization of a stem-like population in hepatocellular carcinoma MHCC97 cells.

A small stem-like subpopulation was isolated from human hepatocellular carcinoma (HCC) MHCC97 cells, characterized by their high efflux ability of the Hoechst 33342 dye. These side population (SP) cells were able to generate a heterogeneous mixture of SP and main population (MP) cells, while the MP cells rarely generated SP cells. Cell cycle analysis also revealed that more SP cells were in the G0 phase. They express higher levels of BCRP1, AFP and CK19 than MP cells. SP cells showed significantly higher viability than MP cells following treatment with doxorubicin or methotrexate. Actin polymerization and migration assays indicate that SP cells have a higher migration capacity and in vivo tumorigenicity of these cells is also higher. Collectively, we conclude that the SP is an enriched source of stem-like cells and may be an effective target for therapy and a useful tool to investigate the HCC tumorigenic and metastatic process.

Improvement of dendritic-based vaccine efficacy against hepatitis B virus-related hepatocellular carcinoma by two tumor-associated antigen gene-infected dendritic cells.

Recently, studies on dendritic cell (DC) vaccine have focused on the development of more effective DC vaccine regimen, such as the application of multiple tumor-associated antigen-targeted DC vaccine. This approach could be used to enhance efficacy of DC-based vaccine against tumors and infectious diseases. In this study, we analyzed whether DC from patients with hepatocellular carcinoma can be infected with the alpha-fetoprotein (AFP) gene and/or HBsAg gene (hepatocellular carcinoma-related antigen). Further, it was examined whether vaccination using these genetically engineered DC can induce stronger therapeutic antitumor immunity. Results revealed that DC infected with AdAFP (adenovirus AFP)/HBsAg can express AFP and HBsAg by reverse transcription-polymerase chain reaction and Western blot techniques. Compared with those before transfection, the expressions of membrane molecules increased dramatically. Specific T cells generated by DCs infected with AdAFP/HBsAg specifically recognized human leukocyte antigen-matched HepG2.2.15 cell lines. Moreover, the cytotoxic activity of cytotoxic T lymphocytes against HepG2.2.15 with DCs expressing AFP was significantly augmented by coinfection with the HBsAg gene. Administration with such vaccine also significantly increased the production of interleukin-12p70 and interferon-gamma. Most importantly, in vivo results suggested that inhibitors of tumor growth were most significant in severe combined immunodeficiency mice model, which was treated with induced cytotoxic T lymphocyte by the AFP/HBsAg-DC vaccine. These results indicate that a vaccination therapy using DCs coinfected with the two tumor-associated antigen genes is an effective strategy for immunotherapy in the activation of DCs, CD4(+) T cells, and CD8(+) T cells, and may be useful in the clinical application of cancer vaccine therapy.

Comparative analysis of DC fused with allogeneic hepatocellular carcinoma cell line HepG2 and autologous tumor cells as potential cancer vaccines against hepatocellular carcinoma.

Fusions of patient-derived dendritic cells (DCs) and autologous tumor cells induce T-cell responses against autologous tumors in animal models and human clinical trials. These fusion cells require patient-derived tumor cells, which are not, however, always available. Here we fused autologous DCs from patients with hepatocellular carcinoma (HCC) to an allogeneic HCC cell line (HepG2). These fusion cells co-expressed tumor-associated antigens (TAAs) and DC-derived costimulatory and MHC molecules. Both CD4(+) and CD8(+) T cells were activated by the fusion cells. Cytotoxic T lymphocytes (CTLs) induced by the fusion cells were able to kill autologous HCC by HLA-A2- and/or HLA-A24-restricted mechanisms. CTL activity against shared TAAs indicates that the presence of alloantigens does not prevent the development of CTLs with activity against autologous HCC cells. These fusion cells may have applications in anti-tumor immunotherapy through cross-priming against shared tumor antigens and may provide a platform for adoptive immunotherapy.

The multifaceted mechanisms for coffee's anti-tumorigenic effect on liver.

Epidemiological studies have found an inverse association between coffee consumption and the risk of liver cancer. Animal data support such a chemopreventive effect of coffee. Substantial research has been devoted to the identification of coffee components that may be responsible for these beneficial effects. Based on the current available literature, three major components, i.e. coffee diterpenes cafestol and kahweol (C+K), caffeine and chlorogenic acid contribute to the beneficial effects. These components induce phase II detoxifying and antioxidant enzymes as well as inhibit the expression or decrease the activity of phase I activating enzymes thus prevent carcinogenesis. These components target different stages of a common pathway, Kelch-like ECH-associated protein 1 (Keap1)--NF-E2-related factor-2 (Nrf2)--antioxidant-responsive-element (ARE) signal pathway thus alter the ARE-dependent expression of genes needed in the anti-tumorigenic effects.

Quantitation assay for absorption and first-pass metabolism of emodin in isolated rat small intestine using liquid chromatography-tandem mass spectrometry.

Emodin has numerous biochemical and pharmacological activities, though information about its intestinal absorption and first-pass metabolism is scarce. The purpose of this study was to evaluate intestinal absorption and metabolism of luminally administered emodin in an isolated rat small intestine using the method of LC/MS/MS. About 22.55% of the administered emodin appeared at the vascular side, chiefly as free emodin (12.01%), but some emodin glucuronide (8.69%) and sulfate (1.84%) were also detected. Free glucuronide (5.23%) and sulfate (1.08%) moieties were found in the luminal perfusate. This model serves as a valuable tool for understanding intestinal handling of emodin, and our results confirm absorption and first-pass metabolism of emodin in the rat small intestine. Phase II metabolic enzymes such as glucuronyl transferase or sulfate transferase may also play an important role in the first-pass metabolism of emodin in the small intestine, which may ultimately reduce the bioavailability (and thus the efficacy) of orally administered emodin.

alpha-fetoprotein and interleukin-18 gene-modified dendritic cells effectively stimulate specific type-1 CD4- and CD8-mediated T-Cell response from hepatocellular carcinoma patients in Vitro.

The T-helper 1 (Th1) immune reaction is most important in dendritic cell (DC)-based immunotherapy. Interleukin (IL)-18, a Th1-biasing cytokine, plays a pivotal role in inducing cytotoxic T lymphocyte (CTL) responses. In this study, we analyzed whether dendritic cells (DCs) from patients with hepatocellular carcinoma (HCC) can be transduced with the IL-18 gene and/or alpha-fetoprotein (AFP) gene, and we examined whether vaccinations using these genetically engineered DC can induce stronger therapeutic antitumor immunity. The results showed that DC transfected with AdIL-18/AFP can expressed IL-18 and AFP by reverse transcriptase-polymerase chain reaction and enzyme-linked immunoassay. Compared with those before transfection, the expressions of membrane molecules were increased dramatically. Specific T cells generated by DC transfected with AdIL-18/AFP recognized HLA-matched HepG2 cell lines specifically. Most importantly, The cytotoxic activity of CTLs against HepG2 with DC expressing AFP(AFP-DC) was significantly augmented by co-transduction with the IL-18 gene. Administration with such vaccine also significantly increased the production of interleukin-12p70 and interferon-gamma. These results indicate that a vaccination therapy using DC co-transduced with the TAA gene and IL-18 genes is effective strategy for immunotherapy in terms of the activation of DCs, CD4+ T, cells and CD8+ T cells, and may be useful in the clinical application of a cancer vaccine therapy.

[Immune response of HBsAg gene-modified dendritic cell-based vaccine in HepG2. 2. 15 hepatocellular carcinoma cells].

OBJECTIVE: To study the cytotoxic T lymphocyte (CTL) response induced by dendritic cells (DC) transduced with recombinant adenovirus vector bearing hepatitis B virus surface antigen (HBsAg) gene in hepatocellular carcinoma HepG2. 2. 15 cells in vitro. METHODS: Full length HBsAg cDNAs were subcloned into pIND vector, followed by being cloned into pShuttle vector. The HBsAg gene fragments resulted from the pShuttle-S digested with PI-Sce and I-Ceu were linked to the linear adeno-X virus DNA. After packaged with HEK293 cells, the adenovirus expression vector was obtained. Then the recombinant adenovirus expression plasmid AdVHBsAg was transfected into human monocyte-derived dendritic cells, to construct AdVHBsAg hepatocarcinoma tumor vaccine. The effectiveness of transfection was detected by Western blot. Surface molecules of AdVHBsAg-DC were detected by FACS. Autologous T cell proliferation stimulated by AdVHBsAg-DC was detected by 3H-TdR assay. Cytotoxic CTL activity induced by AdVHBsAg-DC in vitro was detected by LDH assay. RESULTS: HBsAg gene in the inserted DNA of AdVHBsAg was confirmed by PCR, and predictive fragments proved by restriction enzyme digestion analysis were exhibited. Cell pathological changes appear after 10 days HEK293 cells transfected AdVHBsAg. Western blot analysis showed that HBV surface antigen gene was expressed in transfected DC, indicating that the transfection was effective. AdVHBsAg-DC was able to upregulate CD1a, CD11c, CD80, CD86 and HLA-DR. Autologus T cell proliferation induced by AdVHBsAg-DCs was significantly higher than that in DC control group and LacZ-DC group (P < 0.05). AdVHBsAg-DC activated CTL presented the specific killer ability to the hepatocellular carcinoma cells expressing HBsAg. CONCLUSION: DC transduced with recombinant adenovirus HBsAg can express HBV-related hepatocellular carcinoma antigen (HBsAg), and AdVHBsAg-DC can induce potent immune response against HBsAg-positive hepatocellular carcinoma cells in vitro.

[Effect of vacuum-assisted closure on the expression of urokinase-type plasminogen activator and urokinase-type plasminogen activator receptor in acute and chronic wounds healing].

OBJECTIVE: To study the effect of vacuum-assisted closure (V.A.C) on the expression of Urokinase-type plasminogen activator (uPA) and Urokinase-type plasminogen activator receptor(uPAR) protein in margin tissue of pigs with acute wounds and patients with chronic wounds. METHODS: Acute wounds were created on the two side of five male pigs' back, the experiment wounds on one side received V. A. C treatment and the control side received traditional treatment. Punch biopsies were taken from margin tissue of the wounds in 0, 1, 3, 6, 9, 12, 18, 25 days after the V.A.C treatment. The uPA and uPAR positive cells were stained with immunohistochemical technique . Six human chronic wounds were also treated with the V. A. C treatment, and the samples of extravasate from those wounds were collected in 0, 1, 3, 5, 7 days after the treatment, and the levels of uPA and uPAR expression were examined by enzyme-linked immunosorbent assay (ELISA). RESULTS: The expression of uPA and uPAR protein in margin tissues of pigs with acute wounds increased and peaked in 3 days after the treatment with V. A. C, then it presented rapidly downtrend, but the expression and staining in the experiment group were obviously higher than that of the control group. In the six chronic wounds, the high level expression of uPA and uPAR protein was decreased after the treatment with V. A. C. CONCLUSION: The V. A. C may increase the expression of uPA and uPAR protein in acute wound keratinocytes and decrease the high expression of uPA and uPAR in chronic wounds.

Dendritic cell generated from CD34+ hematopoietic progenitors can be transfected with adenovirus containing gene of HBsAg and induce antigen-specific cytotoxic T cell responses.

Dendritic cells (DCs) are professional antigen presenting cells that are being considered as potential immunotherapeutic agents to promote host immune responses against tumor antigens. The use of such modified antigen-presenting cells for research or therapeutic have been limited by several factors, including maintaining DCs in a highly activated state, efficient transduction and expression, stable expression, identification of appropriate tumor-associated antigens, and absence of unintended functional changes or cytotoxicity. In this study, the feasibility of using CD34-DCs for tumor immunotherapy after transduction with a recombinant adenovirus containing HBsAg gene (AdVHBsAg), an HCC-associated antigen, was investigated. The gene transfer with recombinant adenovirus vectors (AdV) can obtained high levels of stable expression of HBsAg and its efficiency was increased in a multiplicity of infection (MOI)-dependent manner. Moreover, the AdVHBsAg infection had no appreciable effect on apoptosis of DCs compared with that of mock-infected DCs. The T cell lines, primed by the recombinant AdVHBsAg-infected DCs in vitro, recognized HBsAg-expressing tumor cell lines in a human leukocyte antigen (HLA) class I-restricted manner, and evoked a higher CTL response, which indicated that high potent and specific antitumor immune response could be induced by AdVHBsAg DC vaccine. It may be a promising the therapeutic modality for the treatment of HBsAg-expressing tumors, and will be a foundation for further study on DC vaccines and gene therapy for HCC.

[Effect of vacuum-assisted closure on the expression of proto-oncogenes and its significance during wound healing].

OBJECTIVE: To study the effects of VAC on starting the process of wound healing and decreasing apoptosis. METHODS: To examine the variations in expression of proto-oncogenes c-myc, c-jun and Bcl-2 in pig wound model with acute full-thickness skin defect and human chronic wounds by immunohistochemistry, calculate the numbers of expressive positive cells and the labelling index (LI), and observe the process of wound healing. RESULTS: (1) In pig experiment, the wound in experimental group was very clean and without obvious exudates, many neoepiderm and granulation tissue rapidly appeared or formed after 6 days, and healed completely by the 25th day. On the contrary, in the wound of control group, more exudates and blood crust could be seen and fewer neoepiderm and granulation tissue appeared after 6 days and was healed by 30th day. Immediately after the wound was created, the expression of c-myc, c-jun and Bcl-2 was lower and mainly situated in nucleus or cytoplasma of the basilar cells. After the wound was created in control group, or after starting the VAC treatment in experimental group, their expression rapidly and obviously increased, the distribution of the positive cells also became enlarged, but the amount of expression decreased rapidly after the expressive peak have reached. In the successive 12 days following the wound was created, the expression of c-myc, c-jun and Bcl-2 in the experimental group was constantly higher than that of the control group. (2) In human chronic wounds, there wasn't obvious secretions and more healthy granulation tissue was rapidly formed after VAC treatment. The expression of c-jun was mainly located in cytoplasma of basilar cells of epithelium, dermal fibroblasts and inflammatory cells, and the positive cell and labelling index obviously decreased. The expression of c-myc and Bcl-2 was mainly in cytoplasma of basilar cells, but the amount of expression and the labelling index became obviously increased after VAC treatment. CONCLUSIONS: VAC could rapidly start the healing course of the pig' s acute skin wound and human chronic wound, decrease apoptosis of the reparative cells, so as to accelerate wound healing.

[Influence of vacuum-assisted closure technique on expression of Bcl-2 and NGF/NGFmRNA during wound healing].

OBJECTIVE: To explore the influence of vacuum-assisted closure technique (VAC) on expression of Bcl-2 and NGF during wound healing. METHODS: Eighty Sprague-Dawley rats were randomly divided into 4 groups with 20 rats of each. Group T was the experimental group; group C1, C2 and C3 were the control groups. In group T and group C1, capsaicin was injected subcutaneously to the back of the rats to destroy the sensory nerve. VAC was employed to the wound of the rats in group T and C2 three times a day at 80 mmHg negative pressure. In all the groups, tissue samples were taken from the wound edge and granulation at 1, 3, 6, 9 and 12 days after the injury. Immunohistochemistry and in situ hybridization were used to detect the expression of Bcl-2 and NGF/NGFmRNA in the samples. RESULTS: In group C2 and C3, the expression of Bcl-2 and NGF/NGFmRNA was obvious, which increased gradually and reached the peak at the 9th day. In the process of wound healing, the expression Bcl-2 and NGF/NGFmRNA was higher in the group C2 than in group C3 (P < 0.05). The expression Bcl-2 and NGF/NGFmRNA in group T and C1 was lower than group C2 and C3 (P < 0.05). CONCLUSION: The application of the vacuum-assisted closure technique during wound healing increases the expression of the apoptosic modulation related protein Bcl-2 and affects the expression of NGF/NGFmRNA, which may promote the wound healing process.