Hepatitis C virus and hepatocarcinogenesis

Although human hepatocellular carcinoma (HCC) is one of the most common types of tumors in the world, the molecular mechanisms underlying hepatitis-C-related human hepatocarcinogenesis are still not clear. HCC is accompanied by virus infections in most cases, and it is suggested that hepatitis B virus and hepatitis C virus (HCV) significantly influence the oncogenic process. The persistence of inflammation following HCV infection is reportedly related to carcinogenesis, and the mechanism of chronic inflammation has been approached by taking viral, immunologic, cytokine and apoptotic responses into consideration. With the progress made in molecular biology, the functional abnormality of oncogenes/tumor suppressor genes has been identified and, apart from the p53 gene, involvement of the IGF-II gene has also been described recently. Furthermore, it has been suggested that uncontrolled proliferation of cancer cells might be based on abnormal regulation of intracellular signal transduction pathways. Here we review the cutting edge of molecular hepatitis C virology in terms of virus-cell interactions, which may contribute to the development of human HCCs. We also discuss the recent progress made in the molecular and cell biology of human hepatocarcinogenesis.

Correlations between in vitro affinity of antipsychotics to various central neurotransmitter receptors and clinical incidence of their adverse drug reactions

OBJECTIVE

This study was performed to determine whether in vitro affinities of currently available antipsychotics toward dopamine or other neuronal receptor systems are associated with their in vivo incidence of central and peripheral adverse drug reactions (ADRs).

METHODS

For 17 antipsychotic drugs available in Japan, the clinical incidences of 7 different types of drug-induced ADRs (i.e., akathisia, dyskinesia, tremor, rigidity, drowsiness, hypotension and dry mouth) were obtained from both post-marketing ADR databases and the investigational clinical trials of eight pharmaceutical companies. Affinity constants (K(i)) of the respective drugs toward dopamine D(1) and D(2) receptors, alpha(1)-adrenoceptors, histamine H(1) receptors, serotonin 5-HT(2) receptors and muscarinic cholinoceptors, determined using rat brain synaptosomes, were obtained from the literature. Relationships between in vitro receptor-binding properties and in vivo incidences of the respective types of antipsychotic-related ADRs were analyzed using Spearman's rank correlation.

RESULTS

Significant (P < 0.05) correlations were observed between the K(i) values for dopamine D(2) receptor and the clinical incidences of akathisia and dyskinesia (r(s) = -0.68 and -0. 66, respectively). Significant (P < 0.05) correlations were also observed between the K(i) values for alpha(1)-adrenoceptor and histamine H(1) receptor and the incidence of drowsiness (r(s)=-0.65 and -0.55, respectively), and between the K(i) values for three receptor systems (i.e., dopamine D(1) receptor, alpha(1)-adrenoceptor and histamine H(1) receptor) and the incidence of dry mouth (r(s) = -0.50, -0.81 and -0.62, respectively).

CONCLUSION

Preclinical receptor-binding data of antipsychotic drugs toward central dopamine and other ancillary neurotransmitter systems may be useful for predicting not only in vivo antipsychotic potency but also clinical incidence of akathisia and dyskinesia for this class of agents. Newly developed antipsychotic drugs with more potent and selective antagonistic activity against the dopamine D(2) receptor may not necessarily be associated with a lower incidence of extrapyramidal ADRs.

Epidemiology of hepatitis B, C, E, and G virus infections and molecular analysis of hepatitis G virus isolates in Bolivia

Prevalence of hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis G virus (HGV), and hepatitis E virus (HEV) was investigated among 574 healthy blood donors in Bolivia. HCV RNA and HGV RNA in the serum were identified by a nested reverse transcription-PCR using primers derived from the 5' untranslated region (5' UTR). We also tested for hepatitis B surface antigen (HBsAg) and for the antibody to HEV. The results revealed that HGV RNA was present in 84 of 574 (14.6%) tested blood donors, whereas HBsAg was detected in only 2 (0.3%) donors, and no individuals positive for HCV RNA were found. Anti-HEV immunoglobulin G (IgG) was detected in 93 (16.2%) individuals and anti-HEV IgM was found in 10 (1.7%) individuals among the same population. Phylogenetic analysis of 44 HGV isolates in the 5' UTR showed that 27 (61%) isolates were genotype 3 (Asian type) and the remaining 17 (39%) isolates were genotype 2 (United States and European type). Moreover, we obtained a full-length nucleotide sequence of the HGV genome (designated HGV-BL230) recovered from a Bolivian blood donor. The BL230 was composed of 9,227 nucleotides and had a single open reading frame, encoding 2,842 amino acid residues. Interestingly, the BL230 belonged to genotype 2 of HGV at the level of a full-length sequence, although this was classified as genotype 3 by a phylogenetic analysis based on the 5' UTR sequence. The BL230 differed from previously reported HGV/hepatitis GB virus type C isolates by 12 to 13% of the nucleotide sequence and 4% of the amino acid sequence. Our data indicate a high prevalence of HGV in native Bolivians, and the major genotype of HGV was type 3.

Room temperature lasing at blue wavelengths in gallium nitride microcavities

Lasing action has been demonstrated at blue wavelengths in vertical cavity surface-emitting lasers at room temperature. The microcavity was formed by sandwiching indium gallium nitride multiple quantum wells between nitride-based and oxide-based quarter-wave reflectors. Lasing action was observed at a wavelength of 399 nanometers under optical excitation and confirmed by a narrowing of the linewidth in the emission spectra from 0.8 nanometer below threshold to less than 0.1 nanometer (resolution limit) above threshold. The result suggests that practical blue vertical cavity surface-emitting lasers can be realized in gallium-nitride-based material systems.

[Self-expanding stent (Wallstent) supported angioplasty for carotid artery stenosis]

We reported the preliminary results of percutaneous transluminal angioplasty (PTA) supported with a self-expanding stent (Wallstent) for the cervical internal carotid artery (i.c.) stenosis in 6 patients (7 lesions). All were male aged from 60 to 79 (mean 70.8). Three patients were symptomatic and 3 were asymptomatic. The procedure was attempted in patients with severe i.c. stenosis according to criteria of NASCET, ECST or ACAS studies and with high risk if carotid endarterectomy (CEA) were performed. In all cases, vascular access was from the femoral artery and angioplasty was performed without cerebral protection. Successful angioplasty was obtained in all cases with no mortality. Stenosis was improved from 82.7% (74-90%) to 17.4% (10-33%). Perioperative complications were seen in only one case with TIA during the postdilatation period, which was supposed to be due to a distal embolism. The preliminary results of PTA supported with self-expanding stent for severe i.c. stenosis were excellent. These results suggested that some patients with severe i.c. stenosis can be treated safely and effectively by stent-supported PTA. However, it is necessary to mark the indications clear and strict, and to follow up these lesions after the procedure, because of the possibility of perioperative ischemic complications and restenosis.

Interferon therapy reduces the risk for hepatocellular carcinoma: national surveillance program of cirrhotic and noncirrhotic patients with chronic hepatitis C in Japan. IHIT Study Group. Inhibition of Hepatocarcinogenesis by Interferon Therapy

BACKGROUND

Previous studies on the effect of interferon therapy on the incidence of hepatocellular carcinoma have not sufficiently assessed degree of liver fibrosis, a major risk factor for hepatocellular carcinoma.

OBJECTIVE

To evaluate the effect of interferon therapy on incidence of hepatocellular carcinoma, adjusting for risk factors, including the degree of liver fibrosis.

DESIGN

Retrospective cohort study.

SETTING

Seven university hospitals and one regional core hospital in Japan.

PATIENTS

2890 patients with chronic hepatitis C who had undergone liver biopsy since 1986. Of these patients, 2400 received interferon and 490 were untreated.

MEASUREMENTS

The degree of liver fibrosis was assessed from stage F0 (no fibrosis) to stage F4 (cirrhosis). Response to interferon was determined virologically and biochemically. Screening for development of hepatocellular carcinoma was performed periodically during an average follow-up of 4.3 years. Effect of interferon therapy on the risk for hepatocellular carcinoma was analyzed by using Cox proportional hazards regression.

RESULTS

Hepatocellular carcinoma developed in 89 interferon-treated patients and in 59 untreated patients. Among untreated patients, the annual incidence of hepatocellular carcinoma increased with the degree of liver fibrosis, from 0.5% among patients with stage F0 or F1 fibrosis to 7.9% among patients with stage F4 fibrosis. The cumulative incidence in treated and untreated patients differed significantly for patients with stage F2 fibrosis (P = 0.0128) and for those with stage F3 fibrosis (P = 0.0011). In multivariate analysis, interferon therapy was associated with a reduced risk for hepatocellular carcinoma (adjusted risk ratio, 0.516 [95% CI, 0.358 to 0.742]; P < 0.001), especially among patients with sustained virologic response (risk ratio, 0.197 [CI, 0.099 to 0.392]), among those with persistently normal serum alanine aminotransferase levels (risk ratio, 0.197 [CI, 0.104 to 0.375]), and among those with alanine aminotransferase levels less than two times the upper limit of normal (risk ratio, 0.358 [CI, 0.206 to 0.622]).

CONCLUSIONS

Interferon therapy significantly reducesthe risk for hepatocellular carcinoma, especially among virologic or biochemical responders.

[Necessity and usefulness of detection by PCR of mecA and aac(6')/aph(2") genes for identification of arbekacin-resistant MRSA]

Arbekacin (ABK)-resistant bacteria (43 strains) isolated as MRSA by regular clinical procedures in Japanese clinics in 1998 were characterized in terms of taxonomic properties, aminoglycoside resistance, and mecA and aac(6')/aph(2") genes linking with ABK-resistant MRSA. Taxonomically the 43 strains fell into Staphylococcus aureus (33 strains) and Enterococcus (10 strains). As to ABK resistance, the 13 strains of MRSA clinically reported as high ABK resistance (128 micrograms/ml or higher) did not show clear high ABK resistance except for 2 strains when their ABK resistance was tested using 0.5% NaCl containing nutrient agar. We designed and established the primers and conditions for PCR to detect the above two resistance genes. PCR analysis of DNAs from the 43 strains clearly indicated that only 33 strains identified taxonomically as S. aureus possessed mecA indicating MRSA and 23 out of them possessed aac(6')/aph(2"). The other 10 strains of MRSA lacking aac(6')/aph(2") were ABK-sensitive. Thus, there were a good correlation between ABK resistance and aac(6')/aph(2") existence. Based on these, it was conclusive that the appropriate ABK resistance test as well as the detection of mecA and aac(6')/aph(2") genes by PCR are necessary and useful to avoid false ABK-resistant MRSA strains.

Interferon therapy reduces the risk for hepatocellular carcinoma: national surveillance program of cirrhotic and noncirrhotic patients with chronic hepatitis C in Japan. IHIT Study Group. Inhibition of Hepatocarcinogenesis by Interferon Therapy

Background

No study has compared the long-term prognoses of hepatitis C patients with hepatitis C virus (HCV) antibody-negative individuals and investigated the effects of interferon (IFN) treatment. To clarify the long-term prognosis of HCV-positive residents of an isolated Japanese island and prospectively investigate the effects of IFN treatment in comparison with the HCV-negative general population.

Methods

HCV antibody was positive in 1,343 (7.6%) of the 17,712 individuals screened. 792 HCV RNA-positive, HBsAg-negative subjects were enrolled. 1,584 HCV antibody-negative, HBsAg-negative general residents were sex- and age-matched to the 792 subjects. A total of 154 <70-year-old patients without liver cirrhosis (LC) or hepatocellular carcinoma (HCC) underwent IFN treatment. The survival rate with all-cause death as the endpoint was determined and causes of death were compared.

Results

The 10- and 20-year survival rates of the hepatitis C and general resident groups were 65.4% and 87.8%, and 40.8% and 62.5%, respectively (p < 0.001; hazard risk ratio, 0.444; 95% confidence interval (CI): 0.389–0.507). There were 167 liver disease-related deaths and 223 deaths from other causes in the hepatitis C group, and 7 and 451, respectively, in the general resident group. Liver disease-related death accounted for 43.8% and 1.5% of deaths in the hepatitis C and general resident groups (p < 0.0001). The cumulative survival rate of the hepatitis C patients without IFN (n = 328) was significantly lower than the gender- and age-matched general resident group (n = 656) (p < 0.0001) but there was no significant difference between the IFN-treated (n = 154) and general resident groups (n = 308).

Conclusions

In the hepatitis C group, the proportion of liver disease-related death was markedly higher, and the survival rate lower, than the general resident group. Introduction of IFN treatment in <70-year-old patients with hepatitis C without LC or HCC improved the survival rate to a level comparable to that of the general residents.

Blinded, prospective, and serial evaluation by quantitative-EEG in interferon-alpha-treated hepatitis-C

OBJECTIVES

To estimate the effect of brain function due to IFN-alpha in chronic hepatitis C patients by the quantitative EEG.

METHODS

56 chronic hepatitis C patients were administered IFN-alpha intramuscularly at 9x10(6) IU daily for the first 4 weeks and then 3 times/week for the next 20 weeks. Serial EEGs were obtained in each subject before, at 2 and 4 weeks, and after completing the treatment. Resting EEG without artifacts was selected for quantitative EEG analysis, which was performed blindly. The frequency range was divided into delta to beta. The absolute and relative powers of each frequency band in each subject were calculated and the differences of these powers at different stages were analyzed statistically.

RESULTS

The absolute powers of slow waves (delta, theta 1, and theta 2) increased while alpha 2 and fast wave (beta) decreased significantly at all locations during IFN-alpha administration. The total power and alpha 1 values revealed no significant alterations. The relative power revealed the same alteration during treatment. These changes disappeared following the treatment. Such diffuse slowing in the EEG was revealed by the total change in the whole subjects.

CONCLUSIONS

Diffuse slowing in the EEG was induced by IFN-alpha, was reversible, and was evident as the total change in the subjects. These findings suggested mild IFN-alpha-induced encephalopathy.

[Incidence of TT virus infection in patients with non-A to G liver disease]

The sera of patients with liver disease associated with non-A to G hepatitis were examined for the presence of TTV DNA. These patients included 18 cases with AH, 8 cases with CH, 6 cases with LC, 4 cases with HCC, and 36 cases with blood donors. The detection of TTV DNA was performed as described by Nishizawa et al. TTV DNA was detected in 60.0%, 62.5%, 66%, 50%, 28% of the patients with AH, CH, LC and HCC, respectively. Among the patients with AH, the aminotransferases and total bilirubin values were lower in the TTV DNA-positive than -negative patients. Among the patients with chronic liver disease, however, there were no differences in the blood chemistry results between the TTV DNA-positive and -negative patients. The histological study of the liver tissues from a TTV positive patient with CH showed no evidence of necro-inflammatory reaction, although there was evidence of irregular regeneration in the TTV DNA-positive a patient. These results suggest that TTV infection may modify the pathological condition of the liver disease.

[TT virus infection in patients with hepatocellular carcinoma associated with non-A to G hepatitis: histopathological study]

To study if TTV infection is involved in the development of hepatocellular carcinoma (HCC), we tested the sera of 19 patients with HCC associated with non-A to G hepatitis for the presence of serum TTV DNA, and compared the blood chemistry values and liver histology of the patients in the TTV DNA-positive and -negative groups. Detection of TTV DNA was performed described as Nishizawa, et al method. TTV DNA was detected in the sera of 47.4%. There were no significant differences in the blood chemistry results and other tests between the TTV-positive and -negative patients. Histological examination of the non-tumor regions of the liver showed that there were no significant differences in the number of areas and characteristics of the necro-inflammatory reactions, the degree of staging and irregular regeneration of hepatocyte between the two groups. These results suggest that the development of HCC in patients with non-A to G hepatitis is not associated with TTV infection.

Anatomical location of enterochromaffin-like (ECL) cells, parietal cells, and chief cells in the stomach demonstrated by immunocytochemistry and electron microscopy

Enterochromaffin-like (ECL) cells are included in the endocrine cells present in the gastric oxyntic mucosa, and have been attracting attention as histamine-secreting cells contributing to gastric secretion. However, the anatomical location of ECL cells in relation to parietal cells and chief cells has not yet been sufficiently investigated. To elucidate this location of ECL cells, we performed an immunocytochemical study using anti-histamine antibody and electron microscopic examination of guinea pig gastric mucosa. ECL cells were located near the basement membranes in the gastric oxyntic region, and were in contact with both chief cells and parietal cells in the same glandular epithelium. The ratio of ECL cells in contact with chief cells was clearly greater than that in contact with parietal cells. An omega-shaped morphology, indicating emiocytosis, was found in ECL cells by electron microscopy. These findings suggest that ECL cells have a paracrine effect on chief cells and parietal cells, and may have an important physiological role in pepsinogen secretion.

A case of carcinoma associated with the remained intrapancreatic biliary tract 17 years after the primary excision of a choledochal cyst

Although the incidence of biliary carcinoma associated with choledochal cyst is high, there are extremely rare reports about cancer development in the remaining intrapancreatic biliary tract in patients who underwent primary excision of the choledochal cyst. The authors present a case of carcinoma associated with the remnant intrapancreatic biliary tract in a 39 year-old woman, 17 years after the initial excision of a choledochal cyst with Roux-en-Y hepaticojejunostomy. Long-term follow-up may be recommended even in patients who have undergone excisional surgery for choledochal cyst, because it is possible that cancer associated with the intrapancreatic biliary tract may develop.

[Analysis of dynamic CT functional imaging parameters in patients with acute basilar artery occlusion]

It is very important to make a prompt and accurate diagnosis and to commence pertinent treatment for patients suffering from acute cerebrovascular occlusive disease. Thirteen patients (mean age: 67.1 years) with basilar artery occlusion (BAO) were enrolled in this study. Dynamic computed tomography functional images (FID-CT) were analysed to determine whether this method could diagnose BAO in the acute phase. The functional images were categorized into 3 groups: (1) group A (n = 5) showed abnormalities on corrected mean transit time (cMTT) images and time-to-peak (TP) images in the territory of the posterior cerebral artery (PCA) and in the thalamus, (2) group B (n = 6) only showed abnormalities on TP images, and (3) group C (n = 2) had no abnormalities on either cMTT or TP images. The group C patients had poor time-density curves because of heart disease. Although the results may sometimes be false negative and this limitation should be kept in mind, FID-CT seem to be useful not only for defining patients who need angiography but also those who need thrombolytic therapy for acute BAO.

Determination of the clonal origin of multiple human hepatocellular carcinomas by cloning and polymerase chain reaction of the integrated hepatitis B virus DNA

The poor prognosis of hepatocellular carcinoma (HCC) is partly the result of the high rate of recurrence that is caused either by intrahepatic metastasis (IM) or independent multicentric occurrence (MO). For convenience, discrimination of IM and MO is based on pathological findings, but reliable parameters are not sufficiently established. In the case of hepatitis B virus (HBV)-associated HCC, molecular discrimination of IM from MO can be achieved by comparison of integrated HBV DNAs. However, Southern blotting cannot be used for this purpose when one tumor is saved in frozen form and the other is in paraffin-embedded form. To solve this problem, we employed polymerase chain reaction (PCR) assays to confirm the clonality of primary and recurrent tumors. From the frozen tissue, we determined the junction between the integrated HBV and flanking genomic DNA by molecular cloning, and checked the existence of an identical junction in the DNA of paraffin-embedded tissue by PCR. Using this method, as well as Southern blotting, we proved in 6 of 8 patients that two nodular HCC lesions resected metachronously or simultaneously were caused by MO, while the remaining 2 cases were caused by IM. In 1 IM case, band patterns between two HCCs detected by Southern blotting were not identical.

Resonant photorefractive effect in InGaAs/GaAs multiple quantum wells

Semi-insulating InGaAs/GaAs multiple quantum wells are fabricated by metal-organic vapor-phase epitaxy and proton implantation. Two-wave mixing gain and four-wave mixing diffraction efficiency are measured at wavelengths of 0.91-0.94microm in the Franz-Keldysh geometry. We observe a large photorefractive effect caused by the excitonic electro-optic effect. The maximum diffraction efficiency reaches ~1.5x10(-4) .

Development and clinical application of high performance liquid chromatography for the simultaneous determination of plasma levels of theophylline and its metabolites without interference from caffeine

A high performance liquid chromatography (HPLC) method has been developed for the simultaneous determination of plasma levels of theophylline and its metabolites without interference from caffeine or caffeine metabolites. The method is simple and of practical use because it is applicable even to plasma samples from patients who take caffeine-containing beverages. The method was also reproducible with a coefficient of variation of less than 5% for each analyte. The levels of theophylline, determined by HPLC, were validated by their high correlation to the levels obtained by fluorescence polarization immunoassay. HPLC was used to determine theophylline levels in patients with bronchial asthma. The data revealed that the ratio of 1,3-dimethyluric acid, the major metabolite of theophylline, to theophylline concentration in the plasma was within a narrow range in most patients (0.055 +/- 0.01, n = 66), regardless of the method of theophylline administration or the time of blood sampling. Conversely, this ratio was as low as 0.027 +/- 0.005 in the patient with a long plasma half-life of theophylline. These results suggest that it may be possible to predict the plasma half-life of theophylline for each patient from a single blood sample. This may be useful when planning theophylline administration, especially in patients with abnormal theophylline metabolism.

Host genes affecting survival period of chemically induced bladder cancer in mice

Treatment of C57BL/6 J (B6) and NON male mice with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) resulted in a high incidence of bladder cancer. The mean survival period, however, differed significantly by strain: 481+/-219 days in B6 (n = 31) and 203+/-119 days in NON (n = 30) (P < 0.0001). Major causes of death were renal failure due to obstruction of the urinary tract, or local invasion of tumors. The fact that the BBN-treated NON x B6 reciprocal F1 mice had survival periods as short as those of the parental NON mice suggests a genetically dominant susceptibility in NON or recessive resistance in B6. A linkage analysis of 248 back-cross mice to B6 suggested at least two quantitative trait loci determining the length of the survival period: one was mapped close to D2Mit260 (logarithm of odds, LOD, score 2.21), a microsatellite marker locus 83 cM from the centromere on chromosome 2, and another was close to D6Mit159, 7 cM from the centromere on chromosome 6 (LOD score 2.51).

Gastric epithelial cells stimulate Helicobacter pylori growth

Helicobacter pylori infects only human gastric epithelium, causes gastritis, and is strongly associated with gastroduodenal ulceration and gastric cancer. Colonization of the stomach with H. pylori is accompanied in the acute stage by an increased number of neutrophils in the lamina propria, indicative of gastric inflammation. It is interesting that H. pylori colonizes specifically human gastric-type epithelial cells. We studied whether the presence of gastric epithelial cells influenced H. pylori growth. H. pylori (NCTC 11637) was cultured on Skirrow agar with 7% horse blood. Kato-III cells, a human gastric cancer cell line, were cultured with RPMI 1640 plus 10% fetal bovine serum (FBS). Kato-III cells (10(5)/ml) were cultured with/ without H. pylori (10(8) cfu/ml) with RPMI 1640 + 1% FBS for 3 days. The number of Kato-III cells was counted with a hemacytometer. H. pylori with/without Kato-III cells was cultured with RPMI 1640 + 10% FBS for 2 hours, and plated on Skirrow agar. After 3 days we counted the number of H. pylori colonies. To detect the H. pylori colonies, we used a colony hybridization method. DNA of colonies was transferred to positively charged nylon membrane and hybridized by PCR with Hpl (5'-CTG-GAG-AGA-CTA-AGC-CCT-CC-3') and Hp2 (5'-ATT-ACT-GAC-GCT-GAT-TGT-GC-3')-amplified primers. We previously reported that the number of Kato-III cells was significantly decreased by co-incubation with H. pylori. The number of H. pylori colonies was significantly increased by coincubation with Kato-III cells. We conclude that the presence of human gastric epithelial cells is important for the growth of H. pylori.