Monocyte chemoattractant protein-1 (MCP-1)/CCL2 secreted by hepatic myofibroblasts promotes migration and invasion of human hepatoma cells.

The aim of our study was to investigate whether myofibroblasts and the chemokine monocyte chemoattractant protein-1 (MCP-1)/CCL2 may play a role in hepatocellular carcinoma progression. We observed that hepatic myofibroblast LI90 cells express MCP-1/CCL2 mRNA and secrete this chemokine. Moreover, myofibroblast LI90 cell-conditioned medium (LI90-CM) induces human hepatoma Huh7 cell migration and invasion. These effects are strongly reduced when a MCP-1/CCL2-depleted LI90-CM was used. We showed that MCP-1/CCL2 induces Huh7 cell migration and invasion through its G-protein-coupled receptor CCR2 and, to a lesser extent, through CCR1 only at high MCP-1/CCL2 concentrations. MCP-1/CCL2's chemotactic activities rely on tyrosine phosphorylation of focal adhesion components and depend on matrix metalloproteinase (MMP)-2 and MMP-9. Furthermore, we observed that Huh7 cell migration and invasion induced by the chemokine are strongly inhibited by heparin, by beta-D-xyloside treatment of cells and by anti-syndecan-1 and -4 antibodies. Finally, we developed a 3-dimensional coculture model of myofibroblast LI90 and Huh7 cells and demonstrated that MCP-1/CCL2 and its membrane partners, CCR1 and CCR2, may be involved in the formation of mixed hepatoma-myofibroblast spheroids. In conclusion, our data show that human liver myofibroblasts act on hepatoma cells in a paracrine manner to increase their invasiveness and suggest that myofibroblast-derived MCP-1/CCL2 could be involved in the pathogenesis of hepatocellular carcinoma.

Myeloperoxidase and superoxide dismutase 2 polymorphisms comodulate the risk of hepatocellular carcinoma and death in alcoholic cirrhosis.

UNLABELLED: Alcohol increases reactive oxygen species (ROS) formation in hepatocyte mitochondria and by reduced nicotinamide adenine dinucleotide phosphate oxidases and myeloperoxidase (MPO) in Kupffer cells and liver-infiltrating neutrophils. Manganese superoxide dismutase (MnSOD) converts superoxide anion into hydrogen peroxide, which, unless detoxified by glutathione peroxidase or catalase (CAT), can form the hydroxyl radical with iron. Our aim was to determine whether Ala16Val-superoxide dismutase 2 (SOD2), G-463A-MPO, or T-262C-CAT dimorphisms modulate the risks of hepatocellular carcinoma (HCC) and death in alcoholic cirrhosis. Genotypes and the hepatic iron score were assessed in 190 prospectively followed patients with alcoholic cirrhosis. During follow-up (61.1 +/- 2.7 months), 51 patients developed HCC, and 71 died. The T-262C-CAT dimorphism did not modify hepatic iron, HCC, or death. The GG-MPO genotype did not modify iron but increased the risks of HCC and death. The hazard ratio (HR) was 4.7 (2.1-10.1) for HCC and 3.6 (1.9-6.7) for death. Carriage of one or two Ala-SOD2 allele(s) was associated with higher liver iron scores and higher risks of HCC and death. The 5-year incidence of HCC was 34.4% in patients with both the GG-MPO genotype and one or two Ala-SOD2 alleles, 5.1% in patients with only one of these two traits, and 0% in patients with none of these traits. Corresponding 5-year death rates were 37.6%, 11.6%, and 5%. CONCLUSION: The combination of the GG-MPO genotype (leading to high MPO expression) and at least one Ala-SOD2 allele (associated with high liver iron score) markedly increased the risks of HCC occurrence and death in patients with alcoholic cirrhosis.

Glycosaminoglycan mimetics inhibit SDF-1/CXCL12-mediated migration and invasion of human hepatoma cells.

We have recently reported that the CXC-chemokine stromal cell-derived factor-1 (SDF-1)/CXCL12 induces proliferation, migration, and invasion of the Huh7 human hepatoma cells through its G-protein-coupled receptor CXCR4 and that glycosaminoglycans (GAGs) are involved in these events. Here, we demonstrate by surface plasmon resonance that the chemokine binds to GAG mimetics obtained by grafting carboxylate, sulfate or acetate groups onto a dextran backbone. We also demonstrate that chemically modified dextrans inhibit SDF-1/CXCL12-mediated in vitro chemotaxis and anchorage-independent cell growth in a dose-dependent manner. The binding of GAG mimetics to the chemokine and their effects in modulating the SDF-1/CXCL12 biological activities are mainly related to the presence of sulfate groups. Furthermore, the mRNA expression of enzymes involved in heparan sulfate biosynthesis, such as exostosin-1 and -2 or N-deacetylase N-sulfotransferases remained unchanged, but heparanase mRNA and protein expressions in Huh7 cells were decreased upon GAG mimetic treatment. Moreover, decreasing heparanase-1 mRNA levels by RNA interference significantly reduced SDF-1/CXCL12-induced extracellular signal-regulated kinase 1/2 (ERK 1/2) phosphorylation. Therefore, we suggest that GAG mimetic effects on SDF-1/CXCL12-mediated hepatoma cell chemotaxis may rely on decreased heparanase expression, which impairs SDF-1/CXCL12's signaling. Altogether, these data suggest that GAG mimetics may compete with cellular heparan sulfate chains for the binding to SDF-1/CXCL12 and may affect heparanase expression, leading to reduced SDF-1/CXCL12 mediated in vitro chemotaxis and growth of hepatoma cells.

Glycosaminoglycans and syndecan-4 are involved in SDF-1/CXCL12-mediated invasion of human epitheloid carcinoma HeLa cells.

BACKGROUND: In addition to their physiologic effects in inflammation and angiogenesis, chemokines are involved in cancer pathology. The CXC-chemokine stromal cell-derived factor-1 (SDF-1)/CXCL12 mediates its biological activities through activation of G protein-coupled receptor CXCR4 and binds to glycosaminoglycans (GAGs). METHODS: Using Bio-coat cell migration chambers, specific antagonists, flow cytometry and RNA interference, we evaluate the involvement of heparan sulfate proteoglycans (HSPG) in the SDF-1/CXCL12-induced invasion of human cervix epitheloid carcinoma HeLa cells. RESULTS: The SDF-1/CXCL12-induced cell invasion is dependent on CXCR4. Furthermore, Protein Kinase C delta (PKC delta) and c-jun NH2-terminal kinase/stress-activated protein kinase (JNK/SAPK) are implicated in this event, but not extracellular signal-regulated kinase (ERK) 1/2. Moreover, the invasion of HeLa cells induced by SDF-1/CXCL12 was dependent on matrix metalloproteinase-9 (MMP-9). The pre-incubation of HeLa cells with heparin or with anti-heparan sulfate antibodies or with beta-d-xyloside inhibited SDF-1/CXCL12-mediated cell invasion. Furthermore, the down-regulation of syndecan-4, a heparan sulfate proteoglycan, decreased SDF-1/CXCL12-mediated HeLa cell invasion. GAGs, probably on syndecan-4, are involved in SDF-1/CXCL12-mediated cell chemotaxis. GENERAL SIGNIFICANCE: These data suggest that targeting the glycosaminoglycan/chemokine interaction could be a new therapeutic approach for carcinomas in which SDF-1/CXCL12 is involved.

Syndecan-1 and syndecan-4 are involved in RANTES/CCL5-induced migration and invasion of human hepatoma cells.

BACKGROUND: We previously demonstrated that the CC-chemokine Regulated upon Activation, Normal T cell Expressed and Secreted (RANTES)/CCL5 exerts pro-tumoral effects on human hepatoma Huh7 cells through its G protein-coupled receptor, CCR1. Glycosaminoglycans play major roles in these biological events. METHODS: In the present study, we explored 1/ the signalling pathways underlying RANTES/CCL5-mediated hepatoma cell migration or invasion by the use of specific pharmacological inhibitors, 2/ the role of RANTES/CCL5 oligomerization in these effects by using a dimeric RANTES/CCL5, 3/ the possible involvement of two membrane heparan sulfate proteoglycans, syndecan-1 (SDC-1) and syndecan-4 (SDC-4) in RANTES/CCL5-induced cell chemotaxis and spreading by pre-incubating cells with specific antibodies or by reducing SDC-1 or -4 expression by RNA interference. RESULTS AND CONCLUSION: The present data suggest that focal adhesion kinase phosphorylation, phosphoinositide 3-kinase-, mitogen-activated protein kinase- and Rho kinase activations are involved in RANTES/CCL5 pro-tumoral effects on Huh7 cells. Interference with oligomerization of the chemokine reduced RANTES/CCL5-mediated cell chemotaxis. This study also indicates that SDC-1 and -4 may be required for HepG2, Hep3B and Huh7 human hepatoma cell migration, invasion or spreading induced by the chemokine. These results also further demonstrate the involvement of glycosaminoglycans as the glycosaminoglycan-binding deficient RANTES/CCL5 variant, in which arginine 47 was replaced by lysine, was devoid of effect. GENERAL SIGNIFICANCE: The modulation of RANTES/CCL5-mediated cellular effects by targeting the chemokine-syndecan interaction could represent a new therapeutic approach for hepatocellular carcinoma.

The manganese superoxide dismutase Ala16Val dimorphism modulates iron accumulation in human hepatoma cells.

The Ala/16Val dimorphism incorporates alanine (Ala) or valine (Val) in the mitochondrial targeting sequence of manganese superoxide dismutase (MnSOD), modifying MnSOD mitochondrial import and activity. In alcoholic cirrhotic patients, the Ala-MnSOD allele is associated with hepatic iron accumulation and an increased risk of hepatocellular carcinoma. The Ala-MnSOD variant could modulate the expression of proteins involved in iron storage (cytosolic ferritin), uptake (transferrin receptors, TfR-1 and-2), extrusion (hepcidin), and intracellular distribution (frataxin) to trigger hepatic iron accumulation. We therefore assessed the Ala/Val-MnSOD genotype and the hepatic iron score in 162 alcoholic cirrhotic patients. In our cohort, this hepatic iron score increased with the number of Ala-MnSOD alleles. We also transfected Huh7 cells with Ala-MnSOD-or Val-MnSOD-encoding plasmids and assessed cellular iron, MnSOD activity, and diverse mRNAs and proteins. In Huh7 cells, MnSOD activity was higher after Ala-MnSOD transfection than after Val-MnSOD transfection. Additionally, iron supplementation decreased transfected MnSOD proteins and activities. Ala-MnSOD transfection increased the mRNAs and proteins of ferritin, hepcidin, and TfR2, decreased the expression of frataxin, and caused cellular iron accumulation. In contrast, Val-MnSOD transfection had limited effects. In conclusion, the Ala-MnSOD variant favors hepatic iron accumulation by modulating the expression of proteins involved in iron homeostasis.

Chemokine system polymorphisms, survival and hepatocellular carcinoma occurrence in patients with hepatitis C virus-related cirrhosis.

AIM: To explore the influence of polymorphisms in genes encoding for the chemokines Stromal cell-Derived Factor-1 (SDF-1)/CXCL12 and Monocyte Chemotactic Protein-1 (MCP-1)/CCL2, or for the chemokine receptor CCR5 on the risks of liver-related death and hepatocellular carcinoma (HCC) occurrence in hepatitis C virus (HCV)-infected patients. METHODS: SDF-1 3'A, MCP-1 (-2518) and CCR5-Delta32 polymorphisms, SDF-1 alpha, Regulated upon Activation Normal T cells Expressed and Secreted (RANTES)/CCL5 and MCP-1 serum levels were determined in 120 HCV-infected patients, included at time of cirrhosis diagnosis and prospectively followed-up. RESULTS: During follow-up, 23/120 (19.1%) patients died and 47/120 (39.1%) developed HCC. Carriers and noncarriers of each genetic marker had similar baseline characteristics estimating the severity of liver disease. The occurrence of death or HCC during follow-up was similar among carriers and noncarriers of each polymorphism. There was no association between the carriage of mutated alleles and chemokine serum levels and the latter were not associated with the risks of death or HCC. CONCLUSION: This study suggests the lack of association of SDF-1 3'A, MCP-1 (-2518), CCR5-Delta32 polymorphisms with death and HCC occurrence in cirrhotic HCV-infected patients.

Liver iron, HFE gene mutations, and hepatocellular carcinoma occurrence in patients with cirrhosis.

BACKGROUND & AIMS: The influence of HFE gene mutations and liver iron overload on hepatocellular carcinoma (HCC) occurrence in patients with cirrhosis is subjected to controversial results. The aim of this work was to clarify this influence in a large cohort of prospectively followed-up cirrhotic patients classified according to the cause of their liver disease. METHODS: Three hundred one consecutive cirrhotic patients (162 alcoholics and 139 HCV-infected patients) were included at time of diagnosis of cirrhosis and followed-up. Liver iron overload on initial biopsy according to modified Deugnier's score and C282Y/H63D HFE gene mutations were assessed. RESULTS: In patients with alcoholic cirrhosis (mean iron score, 2.0 +/- 3.0; mean time of follow-up, 66.1 +/- 45.1 months), 40 (24.6%) developed HCC. Thirteen (8.02%) were heterozygotes for C282Y HFE gene mutation and had higher hepatic iron scores (3.6 +/- 3.8 vs 1.9 +/- 2.8, respectively, P = .05). In univariate analysis, liver iron overload as a continuous variable (HR, 1.23 [1.13-1.34], P < .001) or in binary coding with an optimal threshold of iron score >/=2.0 (HR, 4.1 [2.1-7.3], P < .0001) and C282Y mutation carriage (HR, 2.7 [1.2-6.3], P = .01) were risk factors for HCC. In multivariate analysis, liver iron and C282Y mutation carriage remained independent risk factors for HCC. In patients with HCV-related cirrhosis (C282Y mutation carriage, 17 [12.23%]; mean liver iron score, 0.9 +/- 1.9; mean time of follow-up, 85.5 +/- 42.1 months; HCC, 63 [45.32%] patients), C282Y mutation carriage and liver iron were not associated with HCC occurrence. CONCLUSIONS: Liver iron overload and C282Y mutation are associated with a higher risk of HCC in patients with alcoholic but not HCV-related cirrhosis.

Glycosaminoglycans and their synthetic mimetics inhibit RANTES-induced migration and invasion of human hepatoma cells.

The CC-chemokine regulated on activation, normal T-cell expressed, and presumably secreted (RANTES)/CCL5 mediates its biological activities through activation of G protein-coupled receptors, CCR1, CCR3, or CCR5, and binds to glycosaminoglycans. This study was undertaken to investigate whether this chemokine is involved in hepatoma cell migration or invasion and to modulate these effects in vitro by the use of glycosaminoglycan mimetics. We show that the human hepatoma Huh7 and Hep3B cells express RANTES/CCL5 G protein-coupled receptor CCR1 but not CCR3 nor CCR5. RANTES/CCL5 binding to these cells depends on CCR1 and glycosaminoglycans. Moreover, RANTES/CCL5 strongly stimulates the migration and the invasion of Huh7 cells and to a lesser extent that of Hep3B cells. RANTES/CCL5 also stimulates the tyrosine phosphorylation of focal adhesion kinase and activates matrix metalloproteinase-9 in Huh7 hepatoma cells, resulting in increased invasion of these cells. The fact that RANTES/CCL5-induced migration and invasion of Huh7 cells are both strongly inhibited by anti-CCR1 antibodies and heparin, as well as by beta-d-xyloside treatment of the cells, suggests that CCR1 and glycosaminoglycans are involved in these events. We then show by surface plasmon resonance that synthetic glycosaminoglycan mimetics, OTR4120 or OTR4131, directly bind to RANTES/CCL5. The preincubation of the chemokine with each of these mimetics strongly inhibited RANTES-induced migration and invasion of Huh7 cells. Therefore, targeting the RANTES-glycosaminoglycan interaction could be a new therapeutic approach for human hepatocellular carcinoma.

Lack of association of some chemokine system polymorphisms with the risks of death and hepatocellular carcinoma occurrence in patients with alcoholic cirrhosis: a prospective study.

BACKGROUND: Polymorphisms in genes encoding for the chemokines stromal cell-derived factor-1 (SDF-1)/CXCL12, monocyte chemotactic protein-1 (MCP-1)/CCL2, or for the chemokine receptors, CC chemokine receptor 5 (CCR5) or CC chemokine receptor 2 (CCR2) have been associated with the progression of hepatitis C virus-related liver injury and with various cancer development. Their influence on the prognosis of alcoholic liver disease is unknown. PATIENTS AND METHODS: SDF-1 3'A, MCP-1(-2518), CCR5-Delta32 and CCR2-64I polymorphisms, SDF-1alpha, regulated upon activation normal T cells expressed and secreted (RANTES)/CCL5 and MCP-1 sera levels were determined in 222 alcoholic patients, included at the time of cirrhosis diagnosis and prospectively followed up. RESULTS: Carriers and noncarriers of each genetic marker had similar baseline characteristics estimating the severity of liver disease. Mean time of follow-up of the cohort was 62.9+/-43.2 months. One hundred and forty-seven out of 222 (66.3%) patients were alive at the end of the study. The occurrence of death (75/222; 33.7%) or hepatocellular carcinoma (67/222; 30.1%) during follow-up was similar among carriers and noncarriers of each polymorphism. No association between the carriage of mutated alleles and chemokine sera levels was found: CCR5-Delta32/RANTES, SDF-1 3'A/SDF-1alpha and CCR2-64I or MCP-1(-2518)/MCP-1. Baseline RANTES, SDF-1alpha and MCP-1 sera levels were associated neither with the risk of death nor with the risk of hepatocellular carcinoma. CONCLUSIONS: The present study suggests the lack of association of SDF-1 3'A, MCP-1(-2518), CCR5-Delta32 and CCR2-64I polymorphisms with death and hepatocellular carcinoma occurrence in cirrhotic alcoholic patients.

Manganese superoxide dismutase dimorphism and iron overload, hepatocellular carcinoma, and death in hepatitis C virus-infected patients.

BACKGROUND & AIMS: A genetic dimorphism encodes for either alanine (Ala) or valine (Val) in the mitochondrial targeting sequence of manganese superoxide dismutase (MnSOD), and modulates its mitochondrial import and activity. It has been shown that the presence of at least 1 Ala-encoding allele is more frequent in alcoholic patients with cirrhosis than in controls, and increases the risks of liver iron overload, hepatocellular carcinoma (HCC), and death in these patients. The aim of this study was to assess the influence of the Ala-9Val MnSOD dimorphism on the same parameters and events in hepatitis C virus (HCV)-infected patients. METHODS: We compared the MnSOD genotypic distributions in 94 control subjects and 165 patients with HCV-related cirrhosis. Patients were included at the time of liver biopsy examination showing cirrhosis, and were followed-up prospectively. The mean time of follow-up evaluation was 85.7 +/- 43.8 months. RESULTS: The distribution of MnSOD genotypes in HCV-infected patients (25% Val/Val homozygotes, 44% Ala/Val heterozygotes, and 31% Ala/Ala homozygotes) did not differ from the distribution in controls (P = .3). MnSOD genotypes did not influence survival (log-rank test, P = .6; relative risk 1.0; 95% confidence interval, 0.6-1.6) or the risk of HCC occurrence (log-rank test, P = .3; relative risk, 1.1; 95% confidence interval, 0.8-1.6). CONCLUSIONS: Contrary to previous findings in French alcoholic patients, the Ala-encoding MnSOD allele is represented equally in controls and patients with HCV-related cirrhosis, and it does not significantly influence the risks of liver iron overload, HCC, or death in these patients.

Stromal cell-derived factor-1/chemokine (C-X-C motif) ligand 12 stimulates human hepatoma cell growth, migration, and invasion.

In addition to their physiologic effects in inflammation and angiogenesis, chemokines are involved in cancer pathology. The aim of this study was to determine whether the chemokine stromal cell-derived factor 1 (SDF-1) induces the growth, migration, and invasion of human hepatoma cells. We show that SDF-1 G protein-coupled receptor, chemokine (C-X-C motif) receptor 4 (CXCR4), and SDF-1 mRNA are expressed in human hepatoma Huh7 cells, which secrete and bind SDF-1. This binding depends on CXCR4 and glycosaminoglycans. SDF-1 associates with CXCR4, and syndecan-4 (SDC-4), a heparan sulfate proteoglycan at the plasma membrane of Huh7 cells, induces the growth of Huh7 cells by promoting their entry into the cell cycle, and inhibits the tumor necrosis factor-alpha-mediated apoptosis of the cells. SDF-1 also reorganizes Huh7 cytoskeleton and induces tyrosine phosphorylation of focal adhesion kinase. Finally, SDF-1 activates matrix metalloproteinase-9, resulting in increased migration and invasion of Huh7 cells. These biological effects of SDF-1 were strongly inhibited by the CXCR4 antagonist AMD3100, by a glycosaminoglycan, heparin, as well as by beta-D-xyloside treatment of the cells, or by c-jun NH(2)-terminal kinase/stress-activated protein kinase inhibitor. Therefore, the CXCR4, glycosaminoglycans, and the mitogen-activated protein kinase signaling pathways are involved in these events. The fact that reducing SDC-4 expression by RNA interference decreased SDF-1-induced Huh7 hepatoma cell migration and invasion strongly indicates that SDC-4 may be an auxiliary receptor for SDF-1. Finally, the fact that CXCR4 is expressed in hepatocellular carcinoma cells from liver biopsies indicates that the in vitro results reported here could be extended to in vivo conditions.

The shedding of syndecan-4 and syndecan-1 from HeLa cells and human primary macrophages is accelerated by SDF-1/CXCL12 and mediated by the matrix metalloproteinase-9.

We recently demonstrated that stromal cell-derived factor-1 (SDF-1/CXCL12) forms complexes with CXCR4, but also with syndecan-4 expressed by human primary lymphocytes and macrophages, and HeLa cells. We also suggested that syndecan-4 behaves as a SDF-1-signaling molecule. Here, we demonstrate that SDF-1 strongly accelerates the shedding of syndecan-4 ectodomains and to a lesser extent that of syndecan-1 from HeLa cells. The fact that this acceleration was not inhibited by the CXCR4 antagonist AMD3100, anti-CXCR4 mAb 12G5, and CXCR4 gene silencing suggests its CXCR4-independence. Pre-treating the cells with heparitinases I, III, or with the protein kinase C (PKC) inhibitor, bisindolylmaleimide, significantly inhibited this accelerated shedding, which suggests the involvement of both cell-surface heparan sulfate and PKC transduction pathway. In contrast, Map Kinase or NF-kappaB pathway inhibitors had no effect. Moreover, SDF-1 increases the matrix metalloproteinase-9 (MMP-9) mRNA level as well as MMP-9 activity in HeLa cells, and MMP-9 silencing by RNA interference strongly decreases the syndecan-1 and -4 ectodomain shedding accelerated by SDF-1. Finally, SDF-1 also accelerates in a CXCR4-independent manner, the shedding of syndecan-1 and -4 from human primary macrophages, which is significantly inhibited by anti-MMP-9 antibodies. This strongly indicates the role of MMP-9 in these events occurring in both a tumoral cell line and in human primary macrophages. Because MMP-9 plays a crucial role in extracellular matrix degradation during cancer cell metastasis and invasion, and shed ectodomains of syndecans may likely be involved in tumor cell proliferation, these data further indicate the multiplicity of the roles played by SDF-1 on tumor cell biology.

Genetic polymorphisms in antioxidant enzymes modulate hepatic iron accumulation and hepatocellular carcinoma development in patients with alcohol-induced cirrhosis.

Manganese superoxide dismutase (MnSOD) converts the superoxide anion into H(2)O(2), which, unless it is detoxified by glutathione peroxidase 1 (GPx1), can increase hepatic iron and can react with iron to form genotoxic compounds. We investigated the role of Ala/Val-MnSOD and Pro/Leu-GPx1 polymorphisms on hepatic iron accumulation and hepatocellular carcinoma development in patients with alcoholic cirrhosis. Genotypes were determined in 162 alcoholic patients with cirrhosis but without hepatocellular carcinoma initially, who were prospectively followed up for hepatocellular carcinoma development. We found that patients with two Val-MnSOD alleles (slow H(2)O(2) production) and two Pro-GPx1 alleles (presumably quick H(2)O(2) detoxification) had a lower risk of hepatocellular carcinoma development than other patients (chi(2) trend test, P = 0.001; log-rank, P = 0.0009). Indeed, hepatocellular carcinoma percentage was 0% in subjects with this "2Val-MnSOD/2Pro-GPx1" genotype versus 16%, 27%, and 32% in "2Val-MnSOD/1or2Leu-GPx1," "1or2Ala-MnSOD/2Pro-GPx1," and "1or2Ala-MnSOD/1or2Leu-GPx1" patients, respectively. The percentage of patients with stainable hepatic iron increased progressively with these genotypic associations: 22%, 28%, 50%, and 53%, respectively (chi(2) trend test, P = 0.005). Stainable iron was a risk factor for hepatocellular carcinoma (log-rank, P = 0.0002; relative risk, 3.40). In conclusion, polymorphisms in antioxidant enzymes modulate hepatic iron accumulation and hepatocellular carcinoma development in French alcoholic patients with cirrhosis.

Genetic dimorphism in superoxide dismutase and susceptibility to alcoholic cirrhosis, hepatocellular carcinoma, and death.

BACKGROUND AND AIMS: A genetic dimorphism encodes for either alanine (Ala) or valine (Val) in the mitochondrial targeting sequence of manganese superoxide dismutase (MnSOD), and modulates its mitochondrial import. However, the role of this dimorphism in the susceptibility of alcoholic patients to develop cirrhosis is controversial, and its influence on the occurrence of hepatocellular carcinoma (HCC) and death in patients with alcoholic cirrhosis is unknown. METHODS: We compared MnSOD genotypes in 94 control subjects and 264 patients with alcoholic cirrhosis. Patients were included at the time of the first liver biopsy examination showing cirrhosis, and were followed-up prospectively. RESULTS: Alcohol consumption was similar, whatever the patients' genotype. At inclusion, the percentage of Val/Val homozygotes was lower in patients than in controls (16% vs. 31%), whereas the percentage of Ala/Ala homozygotes was higher in patients than in controls (30% vs. 21%) ( P = .008). During follow-up evaluation, only 9% of Val/Val patients developed HCC, vs. 30% and 29% of Ala/Val and Ala/Ala patients, respectively ( P = .02). Only 28% of Val/Val patients died or were transplanted, vs. 49% and 50% of Ala/Val and Ala/Ala patients, respectively ( P = .03). Because of the progressive decrease in surviving Ala patients, the genotypic distribution in patients surviving for 5 or 10 years no longer differed from the genotypic distribution in controls. CONCLUSIONS: The presence of at least 1 Ala MnSOD allele increases the risk for developing cirrhosis in French alcoholics, and increases the rates of HCC development and death in cirrhotic patients.

A syndecan-4/CXCR4 complex expressed on human primary lymphocytes and macrophages and HeLa cell line binds the CXC chemokine stromal cell-derived factor-1 (SDF-1).

The stromal cell-derived factor-1 (SDF-1) is a CXC chemokine, which plays critical roles in migration, proliferation, and differentiation of leukocytes. SDF-1 is the only known ligand of CXCR4, the coreceptor of X4 HIV strains. We show that SDF-1 binds to high- and low-affinity sites on HeLa cells. Coimmunoprecipitation studies demonstrate that glycanated and oligomerized syndecan-4 but neither syndecan-1, syndecan-2, betaglycan, nor CD44 forms complexes with SDF-1 and CXCR4 on these cells as well as on primary lymphocytes or macrophages. Moreover, biotinylated SDF-1 directly binds in a glycosaminoglycans (GAGs)-dependent manner to electroblotted syndecan-4, and colocalization of SDF-1 with syndecan-4 was visualized by confocal microscopy. Glycosaminidases pretreatment of the HeLa cells or the macrophages decreases the binding of syndecan-4 to the complex formed by it and SDF-1. In addition, this treatment also decreases the binding of the chemokine to CXCR4 on the primary macrophages but not on the HeLa cells. Therefore GAGs-dependent binding of SDF-1 to the cells facilitates SDF-1 binding to CXCR4 on primary macrophages but not on HeLa cell line. Finally, an SDF-1-independent heteromeric complex between syndecan-4 and CXCR4 was visualized on HeLa cells by confocal microscopy as well as by electron microscopy. Moreover, syndecan-4 from lymphocytes, monocyte derived-macrophages, and HeLa cells coimmunoprecipitated with CXCR4. This syndecan-4/CXCR4 complex is likely a functional unit involved in SDF-1 binding. The role of these interactions in the pathophysiology of SDF-1 deserves further study.

Interaction of RANTES with syndecan-1 and syndecan-4 expressed by human primary macrophages.

Interaction of RANTES with its membrane ligands or receptors transduces multiple intracellular signals. Whether RANTES uses proteoglycans (PGs) belonging to the syndecan family to attach to primary cells expressing RANTES G-protein-coupled receptors (GPCRs) was investigated. We demonstrate that RANTES specifically binds to high and low affinity binding sites on human monocyte-derived macrophages (MDM). We show by co-immunoprecipitation experiments that RANTES is associated on these cells with syndecan-1 and syndecan-4, but neither with syndecan-2 nor with betaglycan, in addition to CD44 and its GPCRs, CCR5 and CCR1. Glycosaminidases pre-treatment of the monocyte derived-macrophages strongly decreases the binding of RANTES to syndecan-1 and syndecan-4 and also to CCR5, and abolishes RANTES binding to CD44. This suggests that glycosaminoglycans (GAGs) are involved in RANTES binding to the PGs and that such bindings facilitate the subsequent interaction of RANTES with CCR5, on the MDM, characterized by low membrane expression of CCR5. The role of these interactions in the pathophysiology of RANTES deserves further study.

Hypovitaminosis C in hospitalized patients.

BACKGROUND: In recent years, cases of scurvy have mainly been described in populations at risk. The prevalence and risk factors for hypovitaminosis C among hospitalized patients in a department of internal medicine are largely unknown. METHODS: We determined serum ascorbic acid level (SAAL) and searched for clinical and biological signs of scurvy in 184 patients hospitalized during a 2-month period. RESULTS: The prevalence of hypovitaminosis C (depletion: SAAL<5 mg/l or deficiency: SAAL<2 mg/l ) was 47.3%. Some 16.9% of the patients had vitamin C deficiency. There was a strong association between hypovitaminosis C and the presence of an acute phase response (p=0.002). Other univariate risk factors for vitamin C depletion were male sex (p=0.02), being retired (p=0.037), and infectious diseases (p=0.002). For vitamin C deficiency, the significant univariate risk factors included the same ones found for vitamin C depletion, plus being unemployed (p=0.003) and concomitant excessive alcohol and tobacco consumption (p<0.0001). Logistic regression showed that being retired (p=0.015) and concomitant excessive alcohol and tobacco consumption (p=0.0003) were significant independent risk factors. Hemorrhagic syndrome and edema were described more often in patients with vitamin C deficiency than in those with vitamin C depletion or without hypovitaminosis. Clinical signs were more frequent for an ascorbic acid level below 2.5 mg/l. CONCLUSION: Hypovitaminosis C is frequent in hospitalized patients but should be interpreted according to the presence or absence of an acute phase response. The main risk factors are living conditions and excessive alcohol and tobacco consumption.

Human alpha-fetoprotein binds to primary macrophages.

We have previously reported that alpha-fetoprotein (AFP) inhibits infection of human monocyte-derived macrophages (MDM) by R5-HIV-1 strains and that a peptide mimicking the clade B HIV-1 gp120 consensus V3 domain (V3Cs) binds to CCR5. We demonstrate here that AFP binds high- and low-affinity binding sites of MDM, characterized, respectively, by 5.15 and 100nM K(d) values. Heat denaturation or neuraminidase treatment of AFP inhibits this binding, suggesting the involvement of protein-protein and lectin-carbohydrate interactions. Moreover, AFP displaces V3Cs binding to MDM. In addition, MIP-1beta, the most specific CCR5 ligand, displaces AFP binding to MDM (IC(50)=4.3nM). Finally, we demonstrate that AFP binds to a ligand of HIV-gp120 V3Cs domain, CCR5, expressed by MDM and by HeLa cells expressing CCR5. Such binding is not observed in the presence of HeLa cells lacking CCR5. The present results provide strong evidence that AFP directly binds to CCR5 expressed by human primary macrophages and by transfected CCR5+ HeLa cells.