Suppressive effects of transforming growth factor-beta1 produced by hepatocellular carcinoma cell lines on interferon-gamma production by peripheral blood mononuclear cells

Transforming growth factor-beta1 (TGF-beta1) exerts potent immunosuppressive effects. In this study, we investigated the potential role of TGF-beta1 produced by hepatocellular carcinoma (HCC) cell lines in immunosuppression mechanisms. Using the Mv1Lu cell-growth inhibition assay and an enzyme-linked immunosorbent assay (ELISA), we detected optimal levels of TGF-beta1 in the culture supernatants conditioned by the HCC cell lines PLC/PRF/5, Hep3B, and HepG2. To determine the biological activity of TGF-beta1 in the supernatants, we examined the effects of the culture supernatants on the production of interferon (IFN)-gamma induced during the culture of peripheral blood mononuclear cells (PBMCs) stimulated with interleukin (IL)-12. IFN-gamma production of IL-12-stimulated PBMCs in the 1:1 dilution of the acid-activated conditioned medium of PLC/PRF/5, Hep3B, and HepG2 reduced to 14.7 +/- 0.8, 17.3 +/- 9.0, and 35.9 +/- 14.6%, respectively, compared with the value in the culture with control medium (complete culture medium). These results suggest that HCC cells producing TGF-beta1 may reduce the generation or activation of cytotoxic T lymphocytes (CTL) and natural killer (NK) cells, and thus could enhance their ability to escape immune-mediated surveillance.

Identification of genes associated with sensitivity to 5-fluorouracil and cisplatin in hepatoma cells

BACKGROUND

The prognosis of patients with advanced hepatoma is grim. Although chemotherapy is adapted to such patients, the efficacy is low and the outcome cannot be predicted before therapy. In this study, we aimed to identify genes associated with sensitivity to 5-fluorouracil and cisplatin, drugs widely used in treatment, using gene expression profiles.

METHODS

Gene expression was evaluated in eight human hepatoma cell lines using an in-house cDNA microarray including 2300 known genes. The 50% growth inhibitory concentrations (GI50) of 5-fluorouracil and cisplatin were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and designated as chemosensitivity. Genes with expression ratios associated with GI50 were selected using the permutation test.

RESULTS

For 5-fluorouracil and cisplatin, 21 and 40 genes, respectively, were selected. From among the genes associated with 5-fluorouracil and cisplatin, several encoding metabolic enzymes were selected. In addition, several genes involved in the cell cycle and transcription were identified.

CONCLUSIONS

We identified genes that may be associated with sensitivity to 5-fluorouracil and cisplatin. A list of these genes may be useful to elucidate how these drugs work on human hepatoma.

Analysis of the beta-catenin/T cell factor signaling pathway in 36 gastrointestinal and liver cancer cells

We investigated the frequency and mechanism of beta-catenin/T cell factor (Tcf) signaling activation in a panel of 36 human gastrointestinal and liver cancer cell lines. Reporter assay and electrophoretic mobility shift assay revealed that the beta-catenin/Tcf signaling was upregulated in 12 of 12 (100%) colorectal, 5 of 8 (68%) gastric, 2 of 7 (29%) hepatic, and none of 9 pancreatic cancer cell lines. The activation of the pathway was mainly due to the mutation of adenomatous polyposis coli (APC) or beta-catenin, and Tcf-4 was highly expressed in these cell lines with upregulated signaling. Nuclear beta-catenin was observed not only in the signaling-activated cell lines, but also in 14 of 25 (56%) primary gastric cancers, 15 of 20 (75%) colon cancers, 5 of 19 (26%) hepatocellular carcinomas, and none of 13 pancreatic cancers. The presence of signaling-upregulated gastric cancer cell lines with intact APC and beta-catenin suggests the involvement of other mechanisms than mutations of APC or beta-catenin.

Reverse seroconversion of hepatitis B virus after hematopoietic stem cell transplantation

Hepatitis B virus (HBV) reactivation in patients previously positive for hepatitis B surface antibody (HBsAb), so-called reverse seroconversion, has been considered to be a rare complication after hematopoietic stem cell transplantation (HSCT). We experienced two patients who developed reverse seroconversion among nine who were HBsAb positive and Hepatitis B core antibody (HBcAb) positive before HSCT; one after autologous bone marrow transplantation (BMT) and another after allogeneic peripheral blood stem cell transplantation (PBSCT). We reviewed the literature and considered that reverse seroconversion of HBV after HSCT is not uncommon among HBsAb positive recipients. The use of corticosteroids, the lack of HBsAb in donor, and a decrease in serum HBsAb and HBcAb levels may predict reverse seroconversion after HSCT.

Quantity of mutant K-ras gene in pancreatic secretions for diagnosis of pancreatic carcinoma with different assays: analysis of 100 patients

BACKGROUND

Two types of quantitative assay kits for K-ras mutations, PCR-preferential homoduplex formation assay (PHFA) and enriched PCR and enzyme-linked mini-sequence assay (ELMA), were recently developed. The K-ras mutations were analyzed using these assays.

MATERIALS AND METHODS

DNA was extracted from the pancreatic juice which was obtained by endoscopy from 38 patients with pancreatic neoplasms (23 adenocarcinomas and 15 intraductal papillary neoplasms) and from 62 without it.

RESULTS

The results of the two methods were mutually correlative. K-ras mutation was detected at high levels (mutant ras genes occupied >2% of all K-ras genes) in 25 of the 38 cases (66%) with pancreatic neoplasm. It was also detected at high levels in 9 of the 14 cases (64%) with pancreatic cyst. In contrast, the mutant gene was detected at a lower level (<2%) in other cases.

CONCLUSIONS

Quantitative analysis of the mutant ras gene provided a useful tool for diagnosing the pancreatic carcinoma when the percentage of the mutant is high, especially when the types of mutation were either GAT or GTT.

Analysis of apoptotic and antiapoptotic signalling pathways induced by Helicobacter pylori

BACKGROUND AND AIMS

Although it is reported that Helicobacter pylori induces apoptosis on gastric epithelial cells, the mechanism remains unknown. Antiapoptotic effects generated by H pylori have not yet been evaluated.

METHODS

(1) H pylori strains (type 1 wild, TN2-deltacagE, TN2-deltavacA) were cocultured with MKN45, TMK1, and HeLa cells, and cell viability and apoptosis were assessed by trypan blue exclusion and DNA laddering, respectively. (2) Activation of caspases-3, 7, and 8, cytochrome c release from the mitochondria, and Fas, Fas associated death domain protein (FADD), Bax, Bak, and Bcl-X expression were evaluated by immunoblot analysis. (3) To investigate whether nuclear factor kappa B (NFkappaB) activation induced by cag pathogenicity island (PAI) positive H pylori affects antiapoptosis, MKN45 cells stably expressing super-repressor IkappaBalpha were cocultured with H pylori, and cell viability and caspase activation were evaluated. NFkappaB regulated gene expression was also evaluated by ribonuclease protection assay.

RESULTS

(1) Wild-type and deltavacA mutant H pylori induced apoptosis more potently than the deltacagE mutant. Inhibition of cell contact between H pylori and cancer cells and heat killing H pylori diminished cell death. (2) Caspases-3, 7, and 8 were activated time dependently by H pylori as well as by the agonist anti-Fas. Cytochrome c release from mitochondria was observed and was not inhibited by caspase-8 inhibitor. Although protein expression of Fas, FADD, Bax, Bak, and Bcl-X in the whole cell lysates was not changed by H pylori, Bax was decreased from mitochondria free cytosol suggesting that Bax was translocated into mitochondria. (3) Cell death and the activities of caspases-3 and 8 were promoted in MKN45 cells stably expressing super-repressor IkappaBalpha that inhibits NFkappaB activation. Antiapoptotic proteins c-IAP1 and c-IAP2 were upregulated by the wild-type strains.

CONCLUSION

cag PAI positive H pylori is capable of inducing apoptotic effects mainly through the mitochondrial pathway. Antiapoptotic effects mediated by NFkappaB activation were also observed.

Quantitative analysis of K-ras gene mutation in pancreatic tissue obtained by endoscopic ultrasonography-guided fine needle aspiration: clinical utility for diagnosis of pancreatic tumor

OBJECTIVES

Endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) has become established in the diagnosis of pancreatic cancer. The combination of pathological diagnosis and analysis for mutant K-ras gene was investigated to improve the accuracy of diagnosis.

METHODS

EUS-FNA was performed in 34 patients with pancreatic masses (26 adenocarcinomas and eight chronic pancreatitis). Mutant ras gene was analyzed semiquantitatively in the specimens obtained by EUS-FNA as well as in pancreatic juice obtained by ERCP.

RESULTS

Mutant gene was detected at high amounts (more than 2% of total ras genes) in 20 of 26 (77%) specimens of EUS-FNA and in 12 of 19 (63%) of pancreatic juice in cases with pancreatic carcinoma. Cytological diagnosis of malignancy by EUS-FNA was found in 16 of 26 (62%) patients with pancreatic cancer. Accurate diagnosis of the carcinoma was 21 of 26 (81%) by combined cytology and molecular method of EUS-FNA, and increased to 23 of 26 (88%) by adding molecular analysis of pancreatic juice. In contrast, mutant gene was absent or low level despite suspicious cytology in patients with benign pancreatic lesion.

CONCLUSION

Quantitative analysis of mutant ras gene supplemented conventional cytology of EUS-FNA and ERCP. Detection of mutation at high amounts may represent pancreatic cancer, whereas its absence increased the possibility of benign lesion.

Weak association between SEN virus viremia and liver disease

Recently, a novel DNA virus designated SEN virus (SEN-V), which is thought to be related to posttransfusion hepatitis, was discovered. The aim of the present study was to clarify the relationship between SEN-V infection and the development of liver disease. We examined SEN-V from the sera of 21 patients with non-B, non-C hepatocellular carcinoma (HCC) and 13 patients with non-B, non-C chronic liver disease (CLD) without HCC who were admitted to our hospital between 1995 and 1997. Thirty-two patients without liver disease served as controls and were also examined for SEN-V. SEN-V DNA was detected by the nested PCR method after extraction of DNA from serum. SEN-V DNA was detected in 74% (25 of 34) of patients with CLD with or without HCC who were negative for both hepatitis B virus surface antigen and anti-hepatitis C virus antibody. SEN-V DNA was detected in 69% (9 of 13) of CLD patients without HCC and in 76% (16 of 21) of HCC patients. The prevalence of SEN-V was no higher in patients with liver disease than in patients without liver disease (24 of 32; 75%). There were no significant differences in age, sex, liver function, history of blood transfusion, or amount of alcohol intake between SEN-V-positive and SEN-V-negative CLD and HCC patients. Genetic analysis suggested that SEN-V is closely related to the TT virus family. SEN-V was detected at almost the same frequency in patients with and without liver disease. SEN-V does not seem to contribute either to the pathogenesis of liver disease or to the development of HCC from chronic liver disease.

Hepatocellular carcinoma in elderly patients: beneficial therapeutic efficacy using percutaneous ethanol injection therapy

BACKGROUND

The age of patients with hepatocellular carcinoma (HCC) has been increasing worldwide. The objective of this study was to assess the efficacy and safety of percutaneous ethanol injection therapy (PEIT) in elderly patients with HCC.

METHODS

The authors retrospectively analyzed 653 patients who were treated with PEIT between 1985 and 1997. One hundred thirty-seven patients were age > or = 70 years, 90 of 137 patients (66%) were male, and 106 of 137 patients (77%) were positive for hepatitis C virus antibodies. Both survival rates and standardized mortality ratios (SMRs) related to the causes of death were compared between patients age > or = 70 years and patients age < 70 years.

RESULTS

With the exception of greater maximum tumor size in elderly patients age > or = 70 years, the clinical features of tumors and underlying liver disease were similar to those of patients age < 70 years The survival rates after PEIT in patients age > or = 70 years were 83%, 52%, and 27% at 1 year, 3 years, and 5 years, respectively. These results were comparable to the rates for patients age < 70 years (1 year, 90%; 3 years, 65%; and 5 years, 40%). In addition, there was no difference in mortality from extrahepatic disease between the two groups (9.8% for patients age > or = 70 years vs. 9.4% for patients age < 70 years; P > 0.999). The SMR of patients age > or = 70 years who died of causes related to extrahepatic disease (SMR, 0.56; 95% confidence interval [95%CI], 0.18-1.30) was lower compared with the SMR of patients age < 70 years (SMR, 1.75; 95%CI, 1.07-2.71). The SMR of patients age > or = 70 years who died of causes related to liver disease (SMR, 115; 95%CI, 84.1-153.0) was similar to that of patients age < 70 years (SMR, 120; 95%CI, 103.0-138.0).

CONCLUSIONS

These results provide support for the treatment of patients with HCC age > or = 70 years by tumor ablation using PEIT.

Novel nucleoside analogue MCC-478 (LY582563) is effective against wild-type or lamivudine-resistant hepatitis B virus

The emergence of resistant hepatitis B virus (HBV) with the L528M mutation and/or the M552V and M552I mutations in the polymerase gene following long-term lamivudine treatment is becoming an important clinical problem. The aim of this study was to investigate the susceptibility of wild-type and lamivudine-resistant HBV to MCC-478 (LY582563), a novel nucleoside analogue derivative of phosphonomethoxyethyl purine. The susceptibility of wild-type HBV and lamivudine-resistant mutants (M552I, M552V, and L528M/M552V) to MCC-478 was examined by transient transfection of full-length HBV DNA into human hepatoma cells. HBV DNA replication was monitored by Southern blot hybridization, and the effective concentration required to reduce replication by 50% (EC(50)) was determined. The replicative intermediates of wild-type and lamivudine-resistant mutants were progressively diminished by treatment with increasing doses of MCC-478. The MCC-478 EC(50)s were 0.027 microM for wild-type HBV (about 20 times more efficient than lamivudine), 2.6 microM for M552I, 3.3 microM for M552V, and 2.0 microM for L528M/M552V. Wild-type HBV and lamivudine-resistant mutants are susceptible to MCC-478. MCC-478 appears to be a candidate for the treatment of HBV infection and exhibits potent activity against lamivudine-resistant HBV.

Interferon therapy prolonged life expectancy among chronic hepatitis C patients

BACKGROUND & AIMS

The effects of interferon therapy in chronic hepatitis C patients on survival are unclear. Our objective was to analyze survival among a large cohort of chronic hepatitis C patients.

METHODS

We used a retrospective cohort study design in the setting of 7 university hospitals and 1 regional core hospital in Japan. Our study included 2889 patients with histological-proven chronic hepatitis C: 2430 patients received interferon therapy, and 459 patients were untreated. For intervention, the median dose and duration of interferon administration was 480 million units and 137 days, respectively. For measurements, survival status was confirmed by medical records or direct questionnaires. The effect of interferon therapy on survival was assessed by standardized mortality ratio (SMR) based on published mortality among the Japanese general population and by risk ratio calculated by proportional hazards regression.

RESULTS

Thirty of 459 untreated patients, 7 of 817 virologic sustained responders, and 49 of 1613 nonresponders died in 5.4-years follow-up. Fifty-eight (67%) of 86 patient deaths were due to liver diseases (39 to hepatocellular carcinoma). Compared with the general population, overall mortality was high among untreated patients (SMR: 1.9; CI: 1.3-2.8) but not among interferon-treated patients (SMR: 0.9; CI: 0.7-1.1). The risk of death was reduced, compared with untreated patients, among interferon-treated patients (risk ratio for overall death: 0.367; CI: 0.236-0.596; for liver-related death: 0.284; CI: 0.164-0.494) and among sustained responders (risk ratios: 0.148; CI: 0.064-0.343 and 0.050; CI: 0.012-0.216). The risk of liver-unrelated deaths remained unchanged.

CONCLUSIONS

Interferon therapy improved survival of chronic hepatitis C patients by preventing liver-related deaths.

Vertebral fracture and cortical bone changes in corticosteroid-induced osteoporosis

Despite an intriguing understanding of trabecular bone dynamics, little is known about corticosteroid-induced cortical bone loss and fractures. Recently, we verified a steroid-induced decrease in cortical bone volume and density using peripheral quantitative computed tomography (pQCT) in adult asthmatic patients given oral corticosteroids. Subsequently, the pQCT parameters and presence of vertebral fractures were investigated to further clarify the role of cortical bone quality in fractures in 86 postmenopausal (>5 years after menopause) asthmatic patients on high-dose oral steroid (>10 g cumulative oral prednisolone) (steroid group) and 194 age-matched controls (control group). Cortical and trabecular bone was subjected to measurement of various parameters using pQCT (Stratec XCT960). Relative Cortical Volume (RCV) was calculated by dividing the cortical area by the total bone area. Strength Strain Index (SSI) was determined in the radius based on the density distribution around the axis. Spinal fracture was assessed on lateral radiographs. Patients treated with high doses of oral steroid (>10 g cumulative oral prednisolone) were found to have an increased risk of fracture compared with control women receiving no steroid medication (odds ratio, 8.85; 95% CI, 4.21-18.60) after adjustment was made for years since menopause, body mass index and RCV. In both groups, the diagnostic and predictive ability of the pQCT parameters for vertebral fracture was assessed by the areas under their receiver operating characteristic (ROC) curves. All parameters were found to be significant predictors ( p<0.0001) in the control group. In the steroid group, however, the cortical bone mineral density (BMD) ( p = 0.001), RCV ( p<0.0001) and SSI ( p = 0.001) were found to be significant predictors, but not trabecular BMD ( p = 0.176). For comparison between the two groups, thresholds of all parameters for vertebral fracture were also calculated by the point of coincidence of sensitivity with specificity in ROC testing and the 90th percentile value. Although a rise in fracture threshold in the steroid group was suggested, considerable difference in the values obtained by the two methods of calculation precluded any conclusion. High-dose oral steroid administration was associated with an increased risk of fracture. Cortical bone parameters obtained by pQCT could play a role as good predictors of future corticosteroid-induced vertebral fractures.

Interferons specifically suppress the translation from the internal ribosome entry site of hepatitis C virus through a double-stranded RNA-activated protein kinase-independent pathway

Interferon (IFN) therapy is used worldwide as the best available treatment for hepatitis C virus (HCV) infection; however, little is known about how IFN or other drugs work against liver diseases. The effect of 6 drugs (glycyrrhizin, ursodeoxycholic acid, ribavirin, methylprednisolone, IFN-alpha, and IFN-beta) on HCV RNA translation from the HCV internal ribosome entry site (IRES) was investigated, using a bicistronic reporter containing the HCV IRES. IFNs suppressed both cap-dependent and HCV IRES-dependent translation, with HCV IRES-dependent translation being more significantly suppressed. In contrast to HCV IRES, IFN did not suppress either foot-and-mouth disease virus IRES-dependent or encephalomyocarditis virus IRES-dependent translation more than it suppressed cap-dependent translation. Moreover, dominant inhibition of HCV IRES-dependent over cap-dependent translation depended neither on the double-stranded RNA-activated protein kinase activation nor on La protein function. These results indicate a novel antiviral effect of IFNs against HCV.

Risk factors for esophageal variceal bleeding in patients with hepatocellular carcinoma

BACKGROUND/AIMS

To evaluate the risk factors for esophageal variceal bleeding in patients with hepatocellular carcinoma.

METHODOLOGY

103 patients with esophageal varices and hepatocellular carcinoma without previous history of varices bleeding or treatment of varices were followed up and the risk factors for variceal bleeding were evaluated by Cox proportional hazards regression.

RESULTS

During an average of 650 days' follow-up, 17 patients (17%) suffered from variceal bleeding, showing an annual incidence rate of 9.3%. Another 8 patients (8%) underwent endoscopic variceal ligation for the aggravation of esophageal varices. Multivariate analysis showed that the red color sign of varices and the size of tumor (> or = 33 mm) were independently associated with an increased risk of variceal bleeding (Risk Ratio = 20.33, P < 0.0001 and Risk Ratio = 2.64, P = 0.0231, respectively).

CONCLUSIONS

The large size of tumor, as well as the red color sign of varices, was a significant risk factor for variceal bleeding in patients with hepatocellular carcinoma.

The enzymatic basis for the conversion of nonfucosylated to fucosylated alpha-fetoprotein by acyclic retinoid treatment in human hepatoma cells: activation of alpha1-6 fucosyltransferase

The purpose of the present study was to investigate the mechanism by which nonfucosylated alpha-fetoprotein (AFP) is converted to fucosylated AFP in human hepatoma cell lines exposed to acyclic retinoid (AR), an effective drug for the secondary prevention of hepatocellular carcinoma. AR treatment (100 microM) of HepG2 and Hep3B cells significantly increased the activity and mRNA levels of alpha1-6 fucosyltransferase (alpha1-6 FucT), the enzyme responsible for the fucosylation of AFP, leading to an increase in fucosylated glycoproteins as evidenced by lectin binding measurements. Lectin immunoelectrophoresis of AFP obtained from culture media indicated that the relative percentage of nonfucosylated AFP (L1 fraction) was decreased and alpha1-6 fucosylated AFP (L3 fraction) was increased in these hepatoma cell lines after treatment with AR. The total AFP levels were, however, markedly suppressed by AR treatment, and therefore the absolute L3 fraction on the basis of the total AFP present was extremely low. These results demonstrate that AR enhances the conversion of the L1 to the L3 fraction due to the activation of alpha1-6 FucT in human hepatoma cell lines despite clinical outcome with AR treatment and the L3 fraction of AFP. Even though the dramatic decrease in AFP is the limiting factor in the synthesis of the L3 fraction and, therefore, the absolute value of fucosylated AFP is extremely low, the conversion from L1 to L3 as judged by lectin immunoelectrophoresis represents a good marker for the progress of AR treatment.

Analysis of apoptotic and antiapoptotic signalling pathways induced by Helicobacter pylori

BACKGROUND AND AIMS

Although it is reported that Helicobacter pylori induces apoptosis on gastric epithelial cells, the mechanism remains unknown. Antiapoptotic effects generated by H pylori have not yet been evaluated.

METHODS

(1) H pylori strains (type 1 wild, TN2-DeltacagE, TN2-DeltavacA) were cocultured with MKN45, TMK1, and HeLa cells, and cell viability and apoptosis were assessed by trypan blue exclusion and DNA laddering, respectively. (2) Activation of caspases-3, 7, and 8, cytochrome c release from the mitochondria, and Fas, Fas associated death domain protein (FADD), Bax, Bak, and Bcl-X expression were evaluated by immunoblot analysis. (3) To investigate whether nuclear factor kappa B (NFkappaB) activation induced by cag pathogenicity island (PAI) positive H pylori affects antiapoptosis, MKN45 cells stably expressing super-repressor Ikappabetaalpha were cocultured with H pylori, and cell viability and caspase activation were evaluated. NFkappaB regulated gene expression was also evaluated by ribonuclease protection assay.

RESULTS

(1) Wild-type and DeltavacA mutant H pylori induced apoptosis more potently than the DeltacagE mutant. Inhibition of cell contact between H pylori and cancer cells and heat killing H pylori diminished cell death. (2) Caspases-3, 7, and 8 were activated time dependently by H pylori as well as by the agonist anti-Fas. Cytochrome c release from mitochondria was observed and was not inhibited by caspase-8 inhibitor. Although protein expression of Fas, FADD, Bax, Bak, and Bcl-X in the whole cell lysates was not changed by H pylori, Bax was decreased from mitochondria free cytosol suggesting that Bax was translocated into mitochondria. (3) Cell death and the activities of caspases-3 and 8 were promoted in MKN45 cells stably expressing super-repressor Ikappabetaalpha that inhibits NFkappaB activation. Antiapoptotic proteins c-IAP1 and c-IAP2 were upregulated by the wild-type strains.

CONCLUSION

cag PAI positive H pylori is capable of inducing apoptotic effects mainly through the mitochondrial pathway. Antiapoptotic effects mediated by NFkappaB activation were also observed.

Oxygenation abnormalities in normoxemic patients with mild liver cirrhosis

OBJECTIVE

Nitric oxide (NO) production is enhanced in patients with liver cirrhosis (LC). Although most patients with mild LC have neither dyspnea nor platypnea, they might have mild oxygenation abnormalities due to intrapulmonary vasodilatation caused by increased NO. We investigated whether oxygenation abnormalities, such as hypoxemia and orthodeoxia, are present in patients with mild LC.

METHODS

We investigated 148 consecutive patients with biopsy-proven chronic liver diseases such as CH (noncirrhotic chronic hepatitis) (n=46), LC(A), LC(B), and LC(C) (LC Child's A, B, and C) (n=18, 51, 33, respectively). The oxygen saturation by pulse oximetry (SpO2) in the supine and upright positions was determined in patients and controls (normal subjects, n=29). The change in SpO2 on standing was defined as deltaSpO2. NO output in exhaled air was measured in 16 patients.

RESULTS

Four patients [two LC(B) and two LC(C)] had hypoxemia (supine SpO2< or =94% and/or upright SpO2< or =94%). Although there was no intergroup difference in the supine SpO2 or the upright SpO2, the deltaSpO2 decreased [control, +0.2+/-0.6%; CH, +0.1+/-0.9%; LC(A), -0.3+/-0.8%; LC(B), -0.2+/-0.9%; LC(C), -0.5+/-1.1%; mean+/-SD; p=0.005] with worsening liver disease, and the prevalence of desaturation on standing (deltaSpO2< or =-1%) increased [control, 7%; CH, 20%; LC(A), 33%; LC(B), 35%; LC(C), 42%; p=0.01]. The NO output was inversely correlated with deltaSpO2 (r=-0.66, p=0.006).

CONCLUSIONS

Desaturation on standing is present in one-third of normoxemic patients with mild LC of Child's A, and is associated with the severity of liver disease. This postural desaturation is correlated with the exhaled NO, which suggests that intrapulmonary vasodilatation may play some role in this phenomenon.

Relationship between nuclear factor-kappaB activation and virulence factors of Helicobacter pylori in Japanese clinical isolates

BACKGROUND

Several factors have been proposed as a possible virulence determinant of Helicobacter pylori infection. The aim of the present study was to evaluate these candidates in nuclear factor (NF)-kappaBeta activation, which is a critical regulator of genes involved in inflammatory reactions.

METHODS

We determined the status of cagE, iceA, HP0441 (a virB4 homolog), the s1 signal sequence of vacA and babA2 by polymerase chain reaction, all of which are candidate virulence determinants, in 107 H. pylori strains isolated from Japanese patients. Nuclear factor-kappaBeta activation was evaluated by the luciferase reporter assay. The gastric mucosa of the hosts was examined histologically.

RESULTS

The cagE gene was positive in 102 (95.3%) strains, iceA1 was positive in 71 (66.4%) strains, HP0441 was positive in 68 (63.6%) strains, vacA s1 was positive in 105 (98.1%) strains and babA2 was positive in 103 (96.3%) strains. Nuclear factor-kappaBeta was activated by all cagE-positive strains, but was not activated by any of the cagE-negative strains. The status of iceA or HP0441 was not associated with NF-kappaBeta activation. Neutrophil infiltration in gastric mucosa was significantly more severe in patients infected with cagE-positive strains than in patients infected with negative strains. No association was found between the degree of neutrophil infiltration and the status of HP0441 or iceA. Due to very high positivity of vacA s1 and babA2 in Japanese strains, their roles remain to be investigated.

CONCLUSIONS

The cag pathogenicity island (PAI) status, as determined by cagE polymerase chain reaction, but not the status of iceA or HP0441, is closely associated with NF-kappaBeta activation and the degree of gastric mucosal inflammation in the hosts.

Hepatitis C virus core protein inhibits apoptosis via enhanced Bcl-xL expression

Previous studies indicated that hepatitis C virus core protein influences cellular apoptosis. However, the precise mechanisms of the effects are not fully understood. Therefore, in this study, we examined the mechanisms of the effects on cell apoptosis by core protein, using transiently transfected and magnetically collected core-producing HepG2 cells. First, to elucidate the target site of core protein in the apoptotic pathway, we examined the activation of caspases after anti-Fas antibody stimulation. Core protein inhibited the apoptotic cascade downstream from caspase 8 and upstream from caspase 3. Next, to clarify more direct mechanisms of this effect, mRNA levels of several bcl-2-related genes were examined. An RNase protection assay showed that the mRNA of bcl-xl increased in the core-producing cells. We showed that this increase was mediated by the enhancement of bcl-x promoter activity by core protein through an extracellular-regulated kinase pathway. These results suggest that core protein inhibits apoptosis at the mitochondria level through augmentation of Bcl-x expression, resulting in an inhibition of caspase 3 activation.

Expression of p57(KIP2) in hepatocellular carcinoma: relationship between tumor differentiation and patient survival

Cyclins, cyclin-dependent kinases (CDK), and CDK inhibitors (CKI) are frequently altered in neoplasm. p57(KIP2) is a member of the KIP (kinase inhibitory protein) family of CKI and is a potential tumor suppressor gene. p27(KIP1) is the most extensively studied KIP family member with respect to the clinical significance in human neoplasms. However, the clinical significance of p57(KIP2) expression in patients with human cancers, including hepatocellular carcinoma (HCC), remains unknown. This study examined whether p57(KIP2) expression has any impact on clinical behavior of HCC including prognosis. We examined an expression of p57(KIP2) by immunohistochemistry in 101 cases of various liver diseases, including 59 HCC. The p57(KIP2) expression in HCC was analyzed in association with the pathohistologic stage, differentiation, proliferating cell nuclear antigen (PCNA) expression status and several histopathologic factors of possible prognostic value, and patient survival. Immunohistochemical analysis revealed the frequent loss of p57(KIP2) in HCC, especially in moderately and poorly differentiated HCC. By Kaplan-Meier analysis, overall survival was significantly correlated with p57(KIP2) expression and PCNA, and multivariate analysis showed p57(KIP2) was an independent prognostic factor. When the status of p57(KIP2) and PCNA were combined, cases positive for p57(KIP2) and with a low expression of PCNA had a significantly better prognosis than those negative for p57KIP2 and/or with a high expression of PCNA. These data indicate that loss of p57(KIP2) is a frequent event in HCC, especially in poorly differentiated HCC, suggesting that p57(KIP2) might play a role in the differentiation of HCC. In addition, p57(KIP2) expression status is an independent prognostic factor for patients with HCC, and the loss of p57(KIP2) is correlated with poor prognosis. New therapeutic options might be provided by the combination of the loss of p57(KIP2) and expression of PCNA.

alpha-Fetoprotein mRNA in the circulation as a predictor of postsurgical recurrence of hepatocellular carcinoma: a prospective study

alpha-fetoprotein (AFP) messenger RNA (mRNA) has been proposed as a marker of hepatocellular carcinoma (HCC) cells disseminated into the circulation, but its clinical significance remains controversial. We prospectively assessed the prognostic value of AFP mRNA in patients undergoing curative hepatic resection for HCC. Peripheral blood samples were taken from 87 patients before and after surgery to determine the presence of AFP mRNA by use of a reverse-transcription polymerase chain reaction. A primary endpoint was recurrence-free interval. AFP mRNA was detectable preoperatively in 31 patients (36%) and postoperatively in 30 patients (34%). With a median follow-up period of 28 months (range, 3-41 months), HCC recurred in 46 patients (53%). Among 4 groups separated according to preoperative and postoperative AFP mRNA status, patients with consistent positivity of AFP mRNA showed the highest recurrence rate (85%) and trend to distant or multiple recurrence. The recurrence-free interval was significantly shorter in patients with postoperative positivity of AFP mRNA than in those without (53% [95% CI, 36-71] vs. 88% [95% CI, 79-96] at 1 year, 37% [95% CI, 17-57] vs. 60% [95% CI, 46-75] at 2 years; P =.014), whereas the preoperative positivity of AFP mRNA provided no significance (P =.100). Cox's proportional-hazards model identified the postoperative positivity of AFP mRNA as an independent prognostic factor for HCC recurrence (relative risk, 2.33; 95% CI, 1.26-4.34; P =.007). In conclusion, postsurgical recurrence of HCC can be predicted by detecting AFP mRNA-expressing cells in peripheral blood.