Antisense oligonucleotides of hepatoma-derived growth factor (HDGF) suppress the proliferation of hepatoma cells

BACKGROUND/AIMS: Human hepatoma-derived growth factor, purified from the conditioned medium of hepatoma-derived cell line, HuH-7, stimulates the growth of Swiss 3T3 fibroblasts and HuH-7 cells. To evaluate the role of hepatoma-derived growth factor on the growth of hepatoma cells, we investigated the effects of recombinant hepatoma-derived growth factor protein and hepatoma-derived growth factor antisense oligonucleotides on the proliferation of several hepatoma cell lines. METHODOLOGY: We examined the effects of hepatoma-derived growth factor antisense oligonucleotides on the growth of hepatoma cells by cell growth assay. RESULTS: Hepatoma-derived growth factor stimulated the proliferation of some hepatoma cells (HuH-7, HLF, HepG2, AH66tc cells) about 15-70% over than the control. Hepatoma-derived growth factor antisense oligonucleotides, phosphorothioate-linked or encapsulated in liposome, can inhibit the growth of hepatoma cells. The ID50 of hepatoma-derived growth factor antisense phosphorothioate oligonucleotides for HuH-7 cells, in which hepatoma-derived growth factor expression was abundant, was 3 microM by the assay of cell proliferation and [3H]-thymidine incorporation. Their ID50 for AH66tc cells, on which the effects of exogenous hepatoma-derived growth factor were weak, was higher than 10 microM. To omit the toxic effects due to phosphorothioate modification of oligonucleotides and keep the cellular uptake more without their destruction in the culture medium, we used oligonucleotides encapsulated in cationic liposome. Hepatoma-derived growth factor antisense oligonucleotides encapsulated in liposome suppressed the growth of hepatoma cells effectively (ID50:2.0 microM). CONCLUSIONS: These findings suggest that hepatoma-derived growth factor is one of important autocrine, and/or intracrine factors for hepatoma cells, and that hepatoma-derived growth factor anti-sense oligonucleotides may be useful for human hepatocellular carcinoma as an anti-cancer agent.     

Alcohol-Metabolizing Enzyme Polymorphisms and Alcoholism in Japan

The liver enzymes, alcohol dehydrogenase (ADH) and aldehyde de-hydrogenase (ALDH), which are responsible for the oxidative metabolism of ethanol, are polymorphic in humans. Cytochrome P450IIE1 , an ethanol-inducible isozyme of liver microsomal P450 , is also important in ethanol metabolism. Genetic polymorphisms in the 5'-flanking region of the human cytochrome P450IIE1 gene have recently been reported. We hypothesized that the polymorphisms of ADH , ALDH , and P450IIE1 modify the susceptibility to development of alcoholism. We determined the genotypes of the ADH2 , ALDH2 , and P450IIE1 loci of 96 Japanese alcoholics and 60 healthy male subjects, using leukocyte DNA by the restriction fragment-length polymorphism by polymerase chain reaction. The alcoholics had significantly higher frequencies of the ADH2 ¹ and ALDH2 ¹ alleles than did the healthy subjects. No significant difference in the frequency of the P45011E1 genotype was observed between the alcoholics and the healthy subjects. In conclusion, genetic polymorphisms of the ADH and ALDH genes, but not of the P45011E1 gene, influence the risk of developing alcoholism in Japanese.     

Gliclazide at a lower concentration than therapeutic dose increases the sensitivity of insulin secretion to glucose in perfused rat pancreas

OBJECTIVES: We studied the difference between effects of therapeutic dose and sub-therapeutic dose of gliclazide on the glucose-induced insulin secretion. METHODS: The normal rat pancreas was isolated and perfused with Krebs-Ringer buffer containing 1-14 mmol/l glucose. Influcences of 0.25 and 2.5 microg/ml gliclazide on the glucose concentration-insulin secretion curve was examined. RESULTS: Gliclazide at 0.25 microg/ml significantly potentiated 5-8 mmol/l glucose-induced insulin secretion (2.5 +/- 0.5 vs 1.0 +/- 0.3 mU for 15 min at 6.5 mmol/l glucose, P<0.01), but did not give influence on either 1-3 or 10-14 mmol/l glucose-induced insulin secretion. The glucose concentration, at which half-maximal insulin secretion was observed, was lower with gliclazide (5.9 mmol/l) than in the control (7.5 mmol/l). Gliclazide at 2.5 microg/ml markedly increased the maximally glucose-stimulated insulin secretion from 3.9 +/- 0.5 mU for 15 min in the control to 6.6 +/- 0.7 mU for 15 min (P<0.01). The half-maximal insulin secretion was observed at a lower glucose concentration (5.0 mmol/l) than in the absence of gliclazide. CONCLUSION: Gliclazide in sub-therapeutically low dose has different effects on insulin secretion from in therapeutic dose, namely sharpens the insulin secretion sensitivity to glucose with no influence on the maximal insulin secretion. It is possible that low doses of gliclazide might be of interest in some type 2 diabetics whose main pathophysiology is the blunting of insulin secretion response to hyperglycemia.     

Role of tissue trace elements in liver cancers and non-cancerous liver parenchyma

BACKGROUND/AIMS: The role of trace elements in liver fibrosis, carcinogenesis and progression of hepatocellular carcinoma (HCC) has not yet been clarified. The aim of this study is to analyze the characteristics of trace elements in liver cancers and non-cancerous liver and to discuss their role in hepatic fibrosis, hepatocarcinogenesis and progression of HCC. METHODOLOGY: The amount of zinc (Zn), iron (Fe), and copper (Cu) in 20 HCCs, 2 cholangiocellular carcinomas (CCC), 7 metastatic liver cancers (Meta) and their non-tumorous liver parenchyma were measured using an atomic absorption spectrophotometer. RESULTS: The amounts of Zn and Fe in non-tumorous liver parenchyma were reduced by liver fibrosis, and the amounts were lower in HCC tissue compared to non-tumorous liver parenchyma. The amounts of Zn and Cu were higher in HCC than the amounts found in CCC and Meta. The amount of Zn in HCC tissue decreased, but the amount of Fe increased in tumors more than 4cm in diameter. CONCLUSIONS: These results suggest that the decrease in the amount of Zn and Fe found in non-tumorous liver parenchyma correlates with liver fibrosis leading to cirrhosis and hepatocarcinogenesis. Also that decreases in Zn and increases of Fe in HCC tissue correlates with HCC tumor progression.     

Cyp11b1 is induced in the murine gonad by luteinizing hormone/human chorionic gonadotropin and involved in the production of 11-ketotestosterone, a major fish androgen: conservation and evolution of the androgen metabolic pathway

We have shown previously that Cyp11b1, an 11beta-hydroxylase responsible for glucocorticoid biosynthesis in the adrenal gland, was induced by cAMP in androgen-producing Leydig-like cells derived from mesenchymal stem cells. We found that Cyp11b1 was induced in male Leydig cells, or female theca cells, when human chorionic gonadotropin was administered in immature mice. Expression of Cyp11b1 in rodent gonads caused the production of 11-ketotestosterone (11-KT), a major fish androgen, which induces male differentiation or spermatogenesis in fish. As in teleosts, plasma concentrations of 11-KT were elevated in human chorionic gonadotropin-treated mice. In contrast to teleosts, however, plasma concentrations of 11-KT were similar in both sexes, despite levels of testosterone, a precursor substrate, being about 20 times higher in male mice. Because expression of 11beta-hydroxysteroid dehydrogenase type 2, was much higher in the mouse ovary than in the testis, conversion of testosterone into 11-KT may occur more efficiently in the ovary. In a luciferase reporter system that was responsive to and activated by androgens, 11-KT efficiently activated mammalian androgen receptor-mediated transactivation. Our results suggest that the androgen metabolic pathway is conserved between teleosts and mammals, despite sexual dominance and reproductive functions of 11-KT being altered during evolution.     

R353Q polymorphism, activated factor VII, and risk of premature myocardial infarction in Japanese men.

BACKGROUND: The association between myocardial infarction (MI) and the R353Q polymorphism of the Factor VII (FVII) gene, which reportedly influences FVII concentrations, activated Factor VII (FVIIa), or FVII antigen (FVIIag), remains controversial. METHODS AND RESULTS: The present case - control study in 127 Japanese men with their first MI at or before 45 years of age and 150 matched healthy controls was designed to clarify this association in premature MI. R353Q polymorphism was determined by polymerase chain reaction, and plasma concentrations of FVIIa and FVIIag were assayed. The distribution of the RR, RQ, and QQ genotypes with respect to R353Q polymorphism was 117, 10, and 0 in the patients, and 131, 17, and 2 in the controls. The Q allele was negatively associated with premature MI (odds ratio =0.41, p=0.038). The plasma concentration of FVIIa was slightly higher in patients (55.1+/-40.9 U/L) than in controls (44.8+/-20.2 U/L), but not significantly (p=0.078); the plasma concentration of FVIIag did not differ between patients (88.7+/-15.7%) and controls (87.0+/-9.0%) (p=0.557). Plasma FVIIa concentrations were influenced by R353Q polymorphism (p<0.001). CONCLUSIONS: The Q allele may be protective against premature MI.     

Serum tenascin levels in chronic liver disease

To evaluate the diagnostic significance of tenascin, the extracellular matrix glycoprotein in chronic liver disease, serum tenascin levels were measured by a newly developed ELISA in 21 patients with chronic persistent hepatitis, in 55 with chronic active hepatitis, in 59 with liver cirrhosis, in 31 with hepatocellular carcinoma, in 26 with acute hepatitis and in 66 healthy subjects. The serum tenascin level was significantly elevated in the patients with chronic active hepatitis, liver cirrhosis, hepatocellular carcinoma, and acute hepatitis when compared with the healthy subjects (P<0.001). The serum tenascin level also increased with increasing severity of chronic liver diseases. A significant correlation was observed between the serum tenascin levels and serum levels of various extracellular matrix proteins such as type III procollagen N-aminoterminal peptide (PIIIP), laminin and the 7S domain of type IV collagen (P<0.001). A strong positive correlation was observed between the serum tenascin levels and histologic findings, particularly in the degree of hepatic fibrosis. This is the first report documenting serum tenascin level increases in patients with various chronic liver diseases. The measurement of the serum tenascin levels may provide additional information relevant to the study of connective tissue.     

Association analysis of toll-like receptor 4 polymorphisms in Japanese primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is characterized by portal inflammation and immune-mediated destruction of intrahepatic bile ducts that often result in liver failure. Toll-like receptor (TLR) 4 recognizes lipopolysaccharides of Gram-negative bacteria. Infectious agents have been suspected to play a crucial role in PBC pathogenesis since TLR4 expression was found in bile duct epithelial cells and periportal hepatocytes in liver tissues of PBC. To assess the potential contribution of TLR4 SNPs to the development of this disease, we genotyped five SNPs in TLR4 in 261 PBC patients and 359 controls using a TaqMan assay. No significant positive associations with either PBC susceptibility or progression were uncovered. These results indicate that TLR4 polymorphisms do not play a prominent role in the development of PBC in Japanese patients.     

E‐cadherin interactions are required for Langerhans cell differentiation

Human skin contains the following two distinct DC subsets: (i) Langerhans cells (LCs), expressing Langerin but not DC‐specific intercellular adhesion molecule‐3‐grabbing nonintegrin (DC‐SIGN), are predominantly localized in the epidermis; and (ii) dermal DCs, expressing DC‐SIGN but not Langerin, are observed mainly in the dermis. It is not known whether localization in the epidermis provides cues for LC differentiation. Here, we show that E‐cadherin expressed by epidermal keratinocytes (KCs) is crucial for differentiation of LCs. Monocytes differentiated into LC‐like cells in presence of IL‐4, GM‐CSF, and TGF‐β1. However, these LC‐like cells expressed not only Langerin but also DC‐SIGN. Notably, co‐culturing of these LC‐like cells with KCs expressing E‐cadherin or recombinant E‐cadherin strongly decreased expression of DC‐SIGN and further induced a phenotype similar to purified epidermal LCs. Moreover, pretreatment of LC‐like cells with anti‐E‐cadherin‐specific antibody completely abolished their Langerin expression, indicating the requirement of E‐cadherin–E‐cadherin interactions for the differentiation into Langerin⁺ cells. These findings suggest that E‐cadherin expressed by KCs provide environmental cues that induce differentiation of LCs in the epidermis.