Influence of alcohol on branched-chain amino acid/tyrosine molar ratio in patients with cirrhosis.

We investigated whether the reduction of plasma tyrosine in alcoholic liver disease would affect the branched-chain amino acid/tyrosine molar ratio (BTR) measured using an enzymatic assay method in alcoholic cirrhosis. BTR values were higher in patients with compensated and decompensated alcoholic cirrhosis (5.68 +/- 2.29 and 3.28 +/- 0.75) due to reduction of the tyrosine level relative to those in patients with nonalcoholic cirrhosis (3.64 +/- 1.22 and 2.53 +/- 0.99). A decrease in tyrosine level and an increase in BTR value were observed after single ethanol administration to healthy subjects. As significant elevation of serum immunoreactive insulin levels followed elevation of serum glucose levels after alcohol loading, it was thought that insulin accelerated intrahepatic metabolism of aromatic amino acids, resulting in reduction of the tyrosine level. The same mechanism may be applied to tyrosine reduction in patients with alcoholic cirrhosis during heavy drinking.

Expression of transforming growth factor alpha and epidermal growth factor receptor in human hepatocellular carcinoma.

Transforming growth factor alpha (TGF-alpha) is thought to be involved in liver regeneration, cellular proliferation, and hepatocarcinogenesis. We have looked at the relationship between TGF-alpha and it's receptor, and have attempted to relate the expression of TGF-alpha and it's receptor to the differentiation of hepatocellular carcinoma (HCC) on serial sections of HCC. We examined immunohistochemically the expression of the TGF-alpha and of epidermal growth factor receptor (EGFR) proteins in the same area of 53 nodules (< 5 cm in diameter) of HCC obtained from patients. Immunoreactive proteins were visualized by using a biotin-streptoavidin system (LSAB Kil, Dako). TGF-alpha was strongly expressed in 29 of 53 (54.7%) nodules. Specimens strongly positive for TGF-alpha were found mainly in well-differentiated HCC, while specimens positive for EGFR were found mainly in poorly differentiated HCC (p < 0.05). In the tissues that stained weakly positive for TGF-alpha, the expression of EGFR differed significantly, according to the degree of HCC histologic differentiation (p < 0.05). These results led us to speculate that the expression of TGF-alpha and EGFR might be related to the pattern of histologic differentiation of HCC.

Indication of chemoembolization therapy without gelatin sponge for hepatocellular carcinoma.

This study evaluated the effect of chemoembolization (C-LIP) consisting of ethiodized oil (Lipiodol Ultra Fluid; André Guerbet, Aulnay-sous-Bois, France) and epirubicin, without gelatin sponge on hepatocellular carcinoma (HCC), administered by hepatic arterial infusion. We analyzed the cases from two points of view: the local recurrence rate for hypervascular solitary small HCC (tumor size: < or =3 cm in diameter) and the cumulative survival rate for advanced HCC (stage VI according to the criteria of Liver Cancer Group of Japan) following C-LIP therapy. The C-LIP also was compared with transcather arterial embolization (TAE; C-LIP followed by gelatin sponge) and percutaneous ethanol injection therapy (PEIT). In the small HCC cases, the recurrence rate at 1 year after C-LIP was 77% (10 of 13 patients), while the local recurrence rate was 46% (six of 13 patients) at 6 months and 61% (eight of 13 patients) at 1 year. The local recurrence rate at 1 year was 29% (four of 14 patients) after TAE and 20% (three of 15 patients) after PEIT. These results showed that the effect of local anticancer therapy by C-LIP was not as potent as that of TAE or PEIT. In advanced HCC cases, the cumulative survival rate for 13 patients treated by C-LIP was 72% at 6 months, 36% at 1 year, and 14% at 2 years. However, the survival rates for 13 patients at 6 months, 1 year, and 2 years after TAE were 46%, 23%, and 8%, respectively. There was no difference between the C-LIP patients and TAE patients with regard to the pretreatment liver function. Three patients died within 2 months after the initial TAE. These deaths were mainly due to damage to the noncancerous liver parenchyma. Therapy with C-LIP alone was not appropriate for hypervascular solitary small HCCs, and additional treatment was necessary. We think C-LIP therapy should be selected instead of TAE for advanced HCCs to avoid severe parenchymal damage.

The assessment of proliferating cell nuclear antigen immunohistochemical staining in small hepatocellular carcinoma and its relationship to histologic characteristics and prognosis.

BACKGROUND: A precise prognostic factor for small hepatocellular carcinoma (HCC), the diagnosis of which recently has increased in incidence because of the development of diagnostic imaging techniques, is desirable. It has been reported that proliferating cell nuclear antigen (PCNA) would be related to proliferating cells, and thus the PCNA labeling index may provide useful information about the biologic behavior of small HCC. METHODS: An assessment was made of proliferative activity by immunohistochemical staining using a monoclonal antibody against PCNA in 46 nodules of HCC less than 3 cm in diameter resected from 44 patients. A correlation between PCNA labeling index and clinicopathologic findings or prognosis was sought. RESULTS: The mean labeling index was 18.7% in HCC and 1.9% in nontumor liver tissue. The labeling index corresponded to the degree of histologic differentiation, and the labeling index of well differentiated HCC was significantly lower (P < 0.05) than that of moderately or poorly differentiated HCC. The incidence of capsule formation in the high labeling index group (labeling index > or = 20%) was significantly higher (P < 0.05) than that in the low labeling index group (labeling index < 20%). A high incidence of capsular and vascular invasion was found in the high labeling index group. The survival rate after resection was significantly higher (P < 0.05) and the recurrence rate significantly lower (P < 0.05) in the low labeling index group than in the high labeling index group. CONCLUSIONS: The PCNA labeling index was shown to be closely related to histologic characteristics, and proved to be a useful indicator of recurrence and survival in small HCC.

Identification and characterization of rat intestinal trefoil factor: tissue- and cell-specific member of the trefoil protein family.

The trefoil peptide family encompasses a group of small proteins that appear to assume a distinctive secondary structure that leads to intrinsic resistance to protease digestion. Induction of these peptides has been associated with response to injury in the gastrointestinal tract and related organs. Using an oligonucleotide derived from N-terminal amino acid sequencing of a transformed growth-inhibiting protein, a cDNA was cloned from rat intestinal villus epithelial cells that encodes a protein 81 amino acids in length with the characteristic trefoil peptide cysteine residue motif. Northern blot analysis demonstrates specific expression of a single transcript of 0.43 kilobase in small and large intestinal epithelium in rat and man. Indirect immunofluorescent staining with antiserum raised using a synthetic peptide based on the predicted C-terminal sequence of this protein, designated intestinal trefoil factor, demonstrated that it is primarily expressed and secreted onto the intestinal surface by goblet cells, suggesting that it may be an important component of intrinsic mechanisms for defending mucosal integrity.

Regulation of transforming growth factor expression in rat intestinal epithelial cell lines.

Autocrine and paracrine modulation of transforming growth factor expression was assessed in rat intestinal epithelial cell lines designated IEC-6 and IEC-7. Addition of the transforming growth factor alpha (TGF alpha) homologue epidermal growth factor (EGF) to media of subconfluent IEC-6 cells led to autocrine stimulation of TGF alpha expression as well as increased expression of the transforming growth factor beta 1 (TGF beta 1). Increased expression of TGF alpha was maximal between 3 and 6 h after addition of EGF and subsequently declined coincident with increasing level of expression of TGF beta 1, which achieved maximal levels 6 h after addition of EGF and was sustained for more than 12 h. Addition of TGF beta 1 also led to autocrine induction of its own expression coincident with suppression of TGF alpha expression. Addition of TGF beta 1 was associated with increased expression of beta-actin when standardized to a constitutive transcript (GAPDH). Similar responses to addition of EGF and TGF beta 1, were observed in another intestinal epithelial cell line, designated IEC-17. Modulation of expression of TGFs was attenuated when cells were grown on the complex extracellular matrix produced by the Engelbreth-Holm-Swarm tumor (Matrigel), reflecting the baseline induction of TGF beta 1 expression when compared to IEC-6 and IEC-17 cells maintained on plastic. These observations suggest that expression of TGFs is controlled by autocrine mechanisms in intestinal epithelial cell lines and proliferation stimulated by TGF alpha may be initially self-reinforcing but ultimately downregulated by induction of TGF beta 1.

Partial purification and characterization of hepatocyte proliferation stimulatory factor from liver of rats treated with D-galactosamine.

The partial purification and characterization of a hepatocyte proliferation stimulatory factor (HPSF) isolated from the liver of D-galactosamine-treated rats are described. The HPSF was a heat-labile, acid-stable and trypsin-sensitive protein. The partially purified HPSF stimulated DNA synthesis and increased the labeling index of parenchymal hepatocytes at 5 micrograms/ml and maximally at 50 micrograms/ml. The effect of HPSF in stimulating DNA synthesis was synergistic with that of insulin plus epidermal growth factor (EGF). The HPSF was scarcely detected in normal rat liver. The results obtained indicate that this HPSF is distinct from insulin, multiplication-stimulating activity (MSA), EGF and other hepatocyte growth factors previously reported, and suggest a plausible role for HPSF in the regeneration of liver tissue following hepatotoxic damage.