Masayoshi Shima

Early recognition of hepatocellular carcinoma based on altered profiles of alpha-fetoprotein.

BACKGROUND The sugar-chain structures of circulating alpha-fetoprotein in patients with hepatocellular carcinomas differ from those in patients with cirrhosis. We studied the reactivity of alpha-fetoprotein with two lectins, Lens culinaris agglutinin A and erythroagglutinating phytohemagglutinin, to monitor the evolution of hepatocellular carcinoma in patients with cirrhosis. METHODS Among 361 patients with cirrhosis caused mainly by chronic hepatitis B or hepatitis C virus infection, 33 with base-line serum alpha-fetoprotein concentrations > or = 30 ng per milliliter or more were found to have hepatocellular carcinomas during a mean follow-up of 35 months. The lectin-reactive profiles of the alpha-fetoprotein in the serum of these 33 patients were analyzed and compared with those in the serum of 32 patients with cirrhosis who had increased base-line serum alpha-fetoprotein concentrations and were followed for at least 24 months but in whom hepatocellular carcinoma did not develop. RESULTS At the time of tumor detection, 24 (73 percent) of the 33 patients with cirrhosis and hepatocellular carcinoma had higher percentages of L. culinaris agglutinin A-reactive alpha-fetoprotein (alpha-fetoprotein L3), erythroagglutinating phytohemagglutinin-reactive alpha-fetoprotein (alpha-fetoprotein P4+P5), or both than the 32 patients with cirrhosis but no hepatocellular carcinoma. Among the 24 patients, one or both of the markers were first elevated 3 to 18 months before the hepatocellular carcinoma was detected by imaging techniques. CONCLUSIONS Measurements of the alpha-fetoprotein L3 and alpha-fetoprotein P4+P5 fractions of serum alpha-fetoprotein allow the differentiation of hepatocellular carcinoma from cirrhosis in some cases and serve as predictive markers for the development of hepatocellular carcinoma during the follow-up of patients with cirrhosis.

Evaluation of Nontumorous Tissue Damage by Transcatheter Arterial Embolization for Hepatocellular Carcinoma

The serial changes in serum hepatic enzyme activities by transcatheter arterial embolization (TAE) were analyzed in 17 patients with hepatocellular carcinoma to estimate the contribution to the value by the damage of tumor or nontumorous hepatic cells. The serum levels of relatively tumor-specific fructose 1,6-diphosphate (FDP) aldolase were elevated after TAE in the cases of both superselective and nonsuperselective TAE that were performed from the segmental and the nonsegmental hepatic artery, respectively, but we found the marked elevation of FDP aldolase in the cases of the superselective TAE. In contrast, the non-tumor-specific fructose 1-phosphate (F1P) aldolase was markedly elevated only in the cases of nonsuperselective TAE. The total amount of FDP aldolase released by TAE correlated significantly with the integrated tumor tissue volume (P less than 0.005), whereas the total amount of F1P aldolase output correlated significantly with the integrated nontumorous tissue volume (P less than 0.005) as defined by lipiodol accumulation on computerized tomography scan. The consequent changes in the total nontumorous liver volumes after TAE were also analyzed by the follow-up computerized tomography scan. The nonsuperselective TAE caused the significant total nontumorous liver atrophy when compared with the superselective TAE. The progression of the total nontumorous liver atrophy correlated significantly with F1P aldolase output by TAE (P less than 0.001) but not with FDP aldolase output. These results suggest that the outputs of FDP and F1P aldolase are useful to estimate the degree of the tumorous and nontumorous tissue damage by TAE, respectively, and F1P aldolase output can be used to predict the progression of liver atrophy caused by TAE.

Changes in HBsAg carrier rate in Goto Islands, Nagasaki Prefecture, Japan

Annual mass examinations in an area where hepatitis B virus (HBV) infection is very prevalent revealed that 12.1% of inhabitants born during 1946-50 were positive for hepatitis B surface antigen (HBsAg), compared with only 0.6% of those born during 1971-75. To find out why the HBV carrier rate has fallen, changes in the modes of HBV infection were examined. The HBsAg positivity rate among mothers who gave birth to HBV carrier children in 1965 and before was 26.8% and that for such mothers whose babies were born in 1966 and after was 66.7%, whereas the HBsAg positivity rate among children born to HBV carrier mothers in 1965 and before and in 1966 and after were 30.8% and 28.3%, respectively. None of the 503 inhabitants who had no HBV markers in 1976 had become carriers by 1981. These findings indicate that the decrease in the prevalence of HBV carriage is caused mainly by the reduction in occurrence of horizontal transmission of HBV in infancy.

Transforming growth factor β1 differentially regulates α-fetoprotein and albumin in HuH-7 human hepatoma cells

Abstract Transforming growth factor β1 (TGF-β1) is known to inhibit hepatocyte growth in vitro and in vivo. In this study, we analyzed the effect of TGF-β1 on α-fetoprotein (AFP) and albumin gene expression in HuH-7 human hepatoma cells. TGF-β1 inhibited cell growth in a dose dependent manner. The cellular secretion rate of AFP but not albumin was suppressed significantly by TGF-β1. TGF-β1 caused a significant reduction in the level of AFP mRNA. In contrast, the levels of albumin mRNA or β-actin mRNA were not changed by TGF-β1. In transient transfection experiments, TGF-β1 resulted in selective repression of AFP promoter activity. These results suggest that TGF-β1 is one of the key factors involved in the differential regulation of the AFP gene and the albumin gene.

Pancreatic tissue damage by transcatheter arterial embolization for hepatoma

We analyzed the serial changes in serum pancreatic enzyme activities by transcatheter arterial embolization (TAE) in 20 hepatoma patients with liver cirrhosis in an attempt to evaluate the incidence of the pancreatic tissue damage by TAE. Serum amylase activities increased in two (10%) cases, elastase 1 levels in six (30%) cases, and trypsin and pancreatic secretory trypsin inhibitor (PSTI) levels in each of five (25%) cases. Consequently, TAE resulted in the elevation of at least more than one serum pancreatic enzyme in eitht (40%) of 20 cases, although none had clinical symptoms related to pancreatitis When the adverse effect on the pancreatic tissue was compared among 6 cases of the superselective TAE and 14 cases of the nonsuperselective TAE, which were perfomed from the segmental and the nonsegmental hepatic arteries, respectively, the elevation of serum pancreatic enzymes was caused only by nonsuperselective TAE, not by superselective TAE. The volumes of Spongel and lipiodol used or the injected doses of the anticancer agent mitomycin C were not different between the two groups. These results indicate that TAE for the treatment of hepatoma frequently causes pancreatic tissue damage, and the position of the inserted catheter tip is very important to avoid the pancreatic tissue damage by TAE.

Interaction of interferon-α with interleukin-1β or tumor necrosis factor-α on hepatitis B virus enhancer activity

Abstract The interaction of IFN-α with IL-1β or TNF-α on hepatitis B surface antigen (HBsAg) expression was analysed in hepatitis B virus (HBV)-DNA integrated PLC/PRF/5 and non-integrated HuH-7 human hepatoma cells. Secretion of HBsAg in PLC/PRF/5 cells was reduced by IFN-α, IL-1β or TNF-α, and synergistically depressed when -α was used in combination with IL-1β or TNF-α. By Northern blot analysis, the levels of HBsAg mRNA were suppressed by IFN-α in combination with IL-1β or TNF-α. In the chloramphenicol acetyltransferase plasmid transfection assay, IFN-α in combination with IL-1β or TNF-α caused a much greater suppression of HBV enhancer activity than IFN-α, IL-1β or TNF-α alone in both hepatoma cells. These findings suggest that the interaction of IFN-α with IL-1β or TNF-α synergistically represses HBV enhancer activity, resulting in depressed expression of HBsAg.

Regulation of albumin and α-fetoprotein gene expression by colloid osmotic pressure in human hepatoma cells

BACKGROUND Colloid osmotic pressure has been thought to regulate albumin synthesis; however, the exact mechanism remains obscure. In the present study, the effect of colloid osmotic pressure on the albumin and alpha-fetoprotein gene expression in HuH-7 human hepatoma cells was analyzed. METHODS HuH-7 cells were treated with albumin or dextran (mean mol wt, 70,000), and changes in the levels of albumin and alpha-fetoprotein messenger RNA (mRNA) were analyzed by Northern blotting. Furthermore, in transient chloramphenicol acetyltransferase (CAT) plasmid transfection experiments, effects of colloid osmotic pressure on CAT activities were studied. RESULTS By Northern blot analysis, the levels of both albumin and alpha-fetoprotein mRNA were dose-dependently suppressed by the elevation of colloid osmotic pressure and returned to pretreatment levels 48 hours after the culture medium containing dextran was replaced with a dextran-free fresh medium. In transient CAT plasmid transfection experiments, the increased level of colloid osmotic pressure resulted in the repression of both albumin and alpha-fetoprotein promoter activities. In contrast, alpha-fetoprotein enhancer activity, which possibly regulates not only alpha-fetoprotein but also albumin gene expression, was not affected by changes in colloid osmotic pressure. CONCLUSIONS These results suggest that colloid osmotic pressure regulates both albumin and alpha-fetoprotein gene transcription through the modulation of their promoter activities.

Inhibitory effect of prostaglandin Δ12-PGJ2 on cell proliferation and α-fetoprotein expression in HuH-7 human hepatoma cells

9-deoxy-Δ9, Δ12-13,14-dihydro-prostaglandin D2 (Δ12-PGJ2) is a potent inhibitor of proliferation of tumor cells. In the present study, the effect of Δ12-PGJ2 on the α-fetoprotein (AFP) and the albumin gene expression was analyzed in HuH-7 human hepatoma cells. Δ12-PGJ2 inhibited the cell growth and reduced the medium AFP concentrations dose-dependently. To determine whether this decline of AFP depends only on the relative decrease in cell numbers by Δ12-PGJ2, or is in part, due to the decrease in the cellular AFP synthesis by Δ12-PGJ2, Northern blot analysis was performed in this study. By Northern blotting, it was shown that Δ12-PGJ2 caused a marked reduction in the levels of the AFP mRNA and the albumin mRNA. In contrast, the level of the β-actin mRNA was not changed by Δ12-PGJ2. In the transient chloramphnicol acetyltransferase plasmid transfection experiments, Δ12-PGJ2 did not suppress the AFP enhancer activity, which possibly regulates both the AFP and the albumin gene expression in HuH-7 hepatoma cells, but resulted in the selective repression of the AFP and the albumin promoter activity. These results suggest that Δ12-PGJ2 suppresses not only cell growth but also expression of the AFP gene and the albumin gene at the transcriptional level in human hepatoma cells.

Enhanced DNA synthesis in rat hepatoma cells by conditioned media from Kupffer cells incubated with supernatants of tumor necrosis factor-α-pretreated hepatocytes

The effects of tumor necrosis factor-alpha (TNF-alpha) on DNA synthesis in AH66 rat hepatoma cells and rat hepatocytes were analysed by means of [3H]thymidine incorporation. DNA synthesis in AH66 cells was suppressed when AH66 cells were directly incubated with TNF-alpha. When primary culture of rat Kupffer cells was incubated with hepatocyte conditioned media pretreated with TNF-alpha (0-200 U/ml), and AH66 cells were then treated with these hepatocyte/Kupffer cell-conditioned media, TNF-alpha used in the pretreatment caused a dose-dependent increase in DNA synthesis in AH66 cells with a maximum effect amounting to a more than 10-fold increase. In contrast, DNA synthesis in primary culture of rat hepatocytes was not stimulated by the TNF-alpha-pretreated hepatocyte/Kupffer cell conditioned media. These results suggest that TNF-alpha-mediated hepatocyte-Kupffer cell interaction selectively promotes proliferation of rat hepatoma cells.