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Non‐hypervascular hypointense nodules (NHHNs) on gadolinium‐ethoxybenzyl‐diethylenetriamine pentaacetic acid–enhanced magnetic resonance imaging (EOB‐MRI) have a high likelihood of hypervascularization progressing to typical hypervascular hepatocellular carcinoma (HCC). NHHNs that were present before the start of anti‐hepatitis C virus (HCV) therapy is a risk marker for HCC development after achieving sustained virologic response (SVR). In this report, we show a patient without a previous history of HCC in whom HCC developed by hypervascularization of NHHN after SVR. This patient achieved SVR more than 8 years before NHHN developed into HCC, and during this time NHHN had been present but had remained unchanged in size and imaging features as shown by repeated EOB‐MRI. Hepatocarcinogenic potential of NHHNs persist for a long time after SVR, despite the eradication of HCV. [ABSTRACT FROM AUTHOR]

Aim: Hypozincemia is associated with the progression of chronic liver diseases, but it is unknown whether hypozincemia promotes human hepatocarcinogenesis. Our aim is to evaluate the serum zinc levels in liver cirrhosis (LC) patients and clarify the relationship between the serum zinc levels and the development of hepatocellular carcinoma (HCC). Methods: Cirrhotic patients without HCC (n = 299) were enrolled from 14 medical institutes in Japan as a multicenter prospective study (No. 2028). Of the 299 patients, 157 were included in the present study based on reliable and consistent serum zinc levels and no history of oral zinc supplementation. Clinical parameters associated with the development of HCC were determined. Furthermore, the cumulative incidence of HCC was analyzed using Kaplan–Meier methods and was calculated using the log–rank test. A Cox regression analysis was utilized for the multivariate analysis to evaluate the predictors of hepatocarcinogenesis. Results: Thirty of 157 patients (19.1%) developed HCC during an observation period of 3 years. Serum zinc levels were significantly decreased in hepatitis C virus‐related LC (C‐LC) patients with HCC (0.0180). The risk factors for incidence of HCC were hypozincemia (0.0014), high α‐fetoprotein (0.0080), low branched chain amino acids‐to‐tyrosine ratio (0.0128), or female sex (0.0228). Hypozincemia (hazard ratio 1.61, 0.0324) was the only significant predictor of hepatocarcinogenesis by multivariate Cox regression analysis. Conclusions: Hypozincemia is associated with hepatocarcinogenesis in C‐LC patients. [ABSTRACT FROM AUTHOR]

Aim Dipeptidyl peptidase-4 (DPP4) inhibitors (DPP4-I) are oral glucose-lowering drugs for type 2 diabetes mellitus. Previously, we reported that DPP4-I (sitagliptin) exerted suppressive effects on experimental liver fibrosis in rats. Blockade of the renin-angiotensin system by angiotensin-II type 1 receptor blocker (losartan), commonly used in the management of hypertension, has been shown to significantly alleviate hepatic fibrogenesis and carcinogenesis. We aimed to elucidate the effects and possible mechanisms of a sitagliptin + losartan combination on the progression of non-diabetic non-alcoholic steatohepatitis (NASH) in a rat model. Methods To induce NASH, Fischer 344 rats were fed a choline-deficient L-amino acid-defined diet for 12 weeks. We elucidated the chemopreventive effects of sitagliptin + losartan, especially in conjunction with hepatic stellate cell (HSC) activation, angiogenesis, and oxidative stress, all known to play important roles in the progression of NASH. Results Sitagliptin + losartan suppressed choline-deficient L-amino acid-defined diet-induced hepatic fibrogenesis and carcinogenesis. The combination treatment exerted a greater inhibitory effect than monotherapy. These inhibitory effects occurred almost concurrently with the suppression of HSC activation, neovascularization, and oxidative stress. In vitro studies showed that sitagliptin + losartan inhibited angiotensin II-induced proliferation and expression of transforming growth factor-β1 and α1 (I)-procollagen mRNA of activated HSC and in vitro angiogenesis, in parallel with the suppression observed in in vivo studies. Conclusions The widely and safely used sitagliptin + losartan combination treatment in clinical practice could be an effective strategy against NASH. [ABSTRACT FROM AUTHOR]

Aim Hepatocarcinogenesis is a multistep process from cirrhosis through low-grade dysplastic nodule, high-grade dysplastic nodule to hepatocellular carcinoma. Differential diagnosis between high-grade dysplastic nodules and early hepatocellular carcinomas is particularly difficult. The present study aims to identify a novel biological marker for differential diagnosis of the two lesions. Methods The expression level of an miRNA pair, miRNA-96-5p and 3p, was assessed by reverse transcription polymerase chain reaction in hepatic tissues. Results We showed that mature miRNA-96-5p and passenger strand miRNA-96-3p were differentially expressed in multistep hepatocarcinogenesis. miRNA-96-5p was significantly upregulated from cirrhosis, dysplastic nodules to hepatocellular carcinoma. However, significance of determination of miRNA-96-5p expression level for differential diagnosis between high-grade dysplastic nodule and hepatocellular carcinoma is limited. In contrast, the expression of miRNA-96-3p was detectable in cirrhosis and dysplastic nodules. Also, it was completely undetectable in the majority of hepatocellular carcinomas (30/34, 88.2%). The sensitivity and specificity of miRNA-96-3p negative expression for differential diagnosis of hepatocellular carcinomas from high-grade dysplastic nodules were 88.2% and 84.2%, respectively. In addition, a more specific diagnosis could be carried out by combining miRNA-96-3p with glypican 3, with the specificity of 100%. Conclusion These findings demonstrated that miRNA-96-3p is a helpful diagnostic biomarker in differential diagnosis between high-grade dysplastic nodules and well-differentiated small hepatocellular carcinomas, especially in combination with glypican 3. [ABSTRACT FROM AUTHOR]

Aim The PNPLA3 rs738409 C> G polymorphism (encoding for I148M) has recently been identified as a susceptibility factor for steatosis-mediated liver damage. We evaluated the influence of this polymorphism on hepatocarcinogenesis in patients with chronic hepatitis C ( CHC) virus infection. Methods We genotyped the rs738409 single nucleotide polymorphism in 358 hepatitis C-associated hepatocellular carcinoma ( HCC) patients and correlated the age at onset of HCC and the interval between hepatitis C virus ( HCV) infection and the development of HCC in patients with each genotype. Results The frequencies of CC, CG and GG genotypes were 27.9% (100/358), 49.2% (176/358) and 22.9% (82/358), respectively, and were in Hardy- Weinberg equilibrium. The median age at onset of HCC for the GG genotype was significantly younger compared to for non- GG genotypes (67.81 vs 69.87 years, P < 0.001), and the median interval between HCV infection and the development of HCC was significantly shorter in patients with the GG genotype (39.96 vs 40.85 years, P = 0.008). PNPLA3 GG genotype was also associated with a higher aspartate aminotransferase level (69.5 vs 59.0 IU/L, P = 0.02), lower prothrombin time (73.0% vs 78.0%, P = 0.008) and a higher prevalence of histological steatosis (40.0% vs. 22.2%, P = 0.01) at the time of HCC onset. Conclusion The PNPLA3 genotype GG may be associated with accelerated hepatocarcinogenesis in CHC patients through increased steatosis in the liver. [ABSTRACT FROM AUTHOR]

Aim It has been reported that branched-chain amino acids ( BCAA) supplementation can improve nutritional status and reduce liver-related complications in patients with decompensated cirrhosis. BCAA supplementation reportedly reduces the incidence of hepatocellular carcinoma ( HCC) in obese cirrhotic patients infected with hepatitis C virus ( HCV). We investigated the effects of oral supplementation with BCAA granules on hepatocarcinogenesis in patients with HCV-related cirrhosis using propensity score matching. Methods A total of 60 patients with HCV-related cirrhosis and without history of HCC who were selected by one-to-one matching of propensity scores: 30 patients receiving 12 g/day of BCAA granules for 3 months or more ( BCAA group) and 30 being observed without BCAA supplementation (control group). The impact of BCAA supplementation was analyzed on the incidence of HCC. Results The 3- and 5-year rates of HCC development were 13.7% and 13.7% in the BCAA group and 35.1% and 44.5% in the control group, respectively. The BCAA group had a significantly lower rate of HCC than the control group ( P = 0.032). Multivariate analysis for factors that were associated with hepatocarcinogenesis indicated that BCAA supplementation was independently associated with a reduced incidence of HCC (hazard ratio 0.131; 95% confidence interval, 0.032-0.530; P = 0.004) along with sex and serum α-fetoprotein. Obesity (body mass index, ≥25 kg/m2) was not significantly associated with an increased incidence of HCC. Conclusion Oral supplementation with BCAA granules is associated with a reduced incidence of HCC in patients with HCV-related cirrhosis regardless of the presence of obesity based on the propensity score analysis. [ABSTRACT FROM AUTHOR]

Aim Insight into hepatic fibrogenesis and carcinogenesis (fibro-carcinogenesis) caused by hepatitis C virus ( HCV) infection has come from recent analyses of transforming growth factor ( TGF)-β signaling. TGF-β type I receptor and pro-inflammatory cytokine-activated kinases differentially phosphorylate Smad2 and Smad3 to create C-terminally ( C), linker ( L) or dually ( L/ C) phosphorylated (p) isoforms. This study aimed to elucidate how HCV infection affected hepatic fibro-carcinogenesis, particularly via phospho-Smad signaling. Methods We first studied phospho- Smad2/3 positivity of 100 patients in different stages of HCV-related chronic liver disease. To examine changes in phospho- Smad2/3 after HCV clearance, we analyzed 32 paired liver biopsy samples obtained before and after sustained virological response ( SVR), dividing patients into two groups: 20 patients not developing hepatocellular carcinoma ( HCC) after attaining SVR (non- HCC group), and 12 patients who developed HCC despite SVR ( HCC group). Results Hepatocytic tumor-suppressive pSmad3C signaling shifted to carcinogenic pSmad3L and fibrogenic pSmad2L/ C signaling as liver diseases progressed. In the non- HCC group, 13 patients (65%) displayed fibrotic regression and inflammation reduction after SVR. Interestingly, SVR restored cytostatic pSmad3C signaling in hepatocytes, while eliminating prior carcinogenic pSmad3L and fibrogenic pSmad2L/ C signaling. In the HCC group, seven patients (58%) displayed unchanged or even progressed fibrosis despite smoothened inflammatory activity, reflecting persistently high numbers of hepatocytes with pSmad3L- and pSmad2L/ C-signaling and low pSmad3C-signaling. Conclusion HCV clearance limits fibrosis and reduces HCC incidence by switching inflammation-dependent phospho- Smad signaling from fibro-carcinogenesis to tumor suppression. However, progression to HCC would occur in severely fibrotic livers if an inflammation-independent fibro-carcinogenic process has already begun before HCV clearance. [ABSTRACT FROM AUTHOR]

Aim Renin is a rate-limiting enzyme of the renin-angiotensin system ( RAS), and several reports have shown that renin plays an important role in several pathological processes. Although RAS is known to play a pivotal role in the progression of non-alcoholic steatohepatitis ( NASH), the role of renin is still obscure. The aim of the current study was to examine the effect of the clinically used direct renin inhibitor ( DRI), aliskiren, on the progression of NASH in a rat model. Methods The effects of DRI on the choline-deficient L-amino acid-defined ( CDAA) diet-induced rat NASH model was examined in conjunction with the activated hepatic stellate cells ( Ac- HSC) and neovascularization, both of which are known to play important roles in liver fibrosis development and hepatocarcinogenesis, respectively. Results DRI exerted a marked inhibitory effect against liver fibrosis development and glutathione- S-transferase placental form ( GST- P) positive preneoplastic lesions along with suppression of the Ac- HSC and neovascularization in a dose-dependent manner. DRI also inhibited the hepatic expressions of transforming growth factor-beta 1 ( TGF-beta 1), angiotensin- II ( AT-II) and vascular endothelial growth factor ( VEGF). These results indicated that renin played a pivotal role in the liver fibrosis development and hepatocarcinogenesis of NASH. Conclusion Because DRI is already widely used in the clinical practice with safety, this drug may represent a potential new strategy against the progression of NASH in the future. [ABSTRACT FROM AUTHOR]

Aim Both angiotensin- II ( AT-II) and aldosterone ( Ald) play pivotal roles in the pathogenesis of diseases in several organs including the liver. We previously reported that suppression of AT-II and Ald with angiotensin-converting enzyme inhibitor ( ACE- I) and selective Ald blocker ( SAB), respectively, attenuated the rat liver fibrogenesis and hepatocarcinogenesis. The aim of our current study was to elucidate the combined effects of ACE- I and SAB in the progression of a non-diabetic rat model of steatohepatitis, and the possible mechanisms involved. Methods In the choline-deficient L-amino acid-defined ( CDAA) diet-induced model, the effects of ACE- I and SAB on liver fibrosis development and hepatocarcinogenesis were elucidated, especially in conjunction with neovascularization. Results Treatment with both ACE- I and SAB suppressed the development of liver fibrosis and glutathione- S-transferase placental form ( GST- P) positive pre-neoplastic lesions. The combined treatment with both agents exerted more inhibitory effects as compared with either a single agent along with suppression of the activated hepatic stellate cells ( Ac- HSC) and neovascularization, both of which play important roles in these processes. Our in vitro study showed that AT-II type 1 receptor blocker ( ARB) and SAB inhibited Ac- HSC proliferation and in vitro angiogenesis along with suppression of the in vivo studies. Conclusion Dual blockade of AT-II and Ald suppresses the progression of a non-diabetic rat model of steatohepatitis. Because both agents are widely and safely used in clinical practice, this combination therapy could be an effective new strategy against steatohepatitis in the future. [ABSTRACT FROM AUTHOR]

In recent years, the effects of hepatitis C virus (HCV) proteins on hepatocarcinogenesis have undergone intense investigations. The potentially oncogenic proteins include at least three HCV proteins: core (C) protein, NS3, and NS5A. Several authors indicated relationships between subcellular localization, concentration, a specific molecular form of the proteins (full length, truncated, phosphorylated), the presence of specific domains (the nuclear localization signal homologous to e.g. Bcl-2) and their effects on the mechanisms linked to oncogenesis. The involvement of all the proteins has been described as being in control of the cell cycle, through interactions with key proteins of the process (p53, p21, cyclins, proliferating cell nuclear antigen), transcription factors, proto-oncogenes, growth factors/cytokines and their receptors, and proteins linked to the apoptotic process. Untilnow, the involvement of the core protein of HCV in liver carcinogenesis is the most recognized. One of the most common proteins affected by HCV proteins is the p53 tumor-suppressor protein. The p21/WAF1 gene is a major target of p53, and the effect of HCV proteins on the gene is frequently considered in parallel. The results of studies on the effects of HCV proteins on the apoptotic process are controversial. This work summarizes the information collected thus far in the field of HCV molecular virology and principal intracellular signaling pathways in which HCV oncogenic proteins are involved. [ABSTRACT FROM AUTHOR]

Overwhelming lines of epidemiological evidence have indicated that persistent infection with hepatitis C virus (HCV) is a major risk toward development of hepatocellular carcinoma (HCC). It remains controversial, however, in the pathogenesis of HCC associated with HCV, whether the virus plays a direct role or merely an indirect one. The studies using transgenic mouse models by us and others, in which the core protein of HCV has oncogenic potential, indicate that HCV is directly involved in hepatocarcinogenesis, albeit other factors such as continued cell death and regeneration associated with inflammation would play a role, as well. The downstream events of the core protein are segregated into two components. One is the augmented production of oxidative stress along with the activation of scavenging system including catalase and glutathion (GSH) in the putative preneoplastic stage with steatosis in the liver. Thus, oxidative stress production in the absence of inflammation by the core protein would partly contribute to the development of HCC. The generation of oxidative stress is estimated to originate from mitochondrial dysfunction in hepatocytes by HCV infection. The other is the alteration of intracellular signaling cascade of MAPK (JNK),AP-1, cyclin D1, and CDK4. The combination of these pathways, collective with HCV-associated alterations in lipid and glucose metabolism, would lead to the frequent development of HCC in persistent HCV infection. Our results suggest that there would be a mechanism for hepatocarcinogenesis in persistent HCV infection that is distinct from those for other cancers. Similar to the pathogenesis of other cancers, the accumulation of a set of genetic aberrations may also be necessary for multistage development of HCC. However, HCV core protein, to which an oncogenic potential is ascribed, may allow some of the multiple steps to be bypassed in hepatocarcinogenesis. Therefore, unlike other cancers, HCV infection can elicit HCC in the absence of a complete set of genetic aberrations. Such a scenario, “non-Vogelstein-type” carcinogenesis, would explain the unusually high incidence and multicentric nature of HCC development in HCV infection. [ABSTRACT FROM AUTHOR]

The present study was aimed to investigate the chemopreventive effects of Solanum trilobatum (ST) extract against diethylnitrosamine (DEN)-induced hepatocarcinogenesis promoted by Phenobarbital (PB) in Wistar rats. Hepatocarcinogenesis was initiated by a single intraperitoneal injection of DEN (200 mg/kg b.w.) and promoted with PB (0.05%) in basal diet. The experimental study extended for periods of 13 and 26 weeks. Alcoholic extract of ST was orally administered for the entire experimental period after initiation along with commencement of promotion. The chemopreventive effect of ST was assessed from the incidence of nodules, drug metabolizing phase I components such as contents of cytochrome P450, cytochrome b5, activities of NADPH cytochrome c reductase, NADH – cytochrome b5 reductase and phase II components such as levels of glutathione, activities of UDP-glucuronyl transferase, glutathione S-transferase and γ-glutamyl transpeptidase in the liver. Lipid peroxidation at basal and prooxidants-induced (NADPH + ADP + Fe and Ascorbate + Fe) states was assessed in the microsomes. Animals administered with ST extract evidenced significant inhibition of tumor nodular incidence in DEN + PB + ST animals compared to DEN + PB animals, with favorable alterations in the hepatic drug-metabolizing phase I and phase II components. Administration of ST inhibited basal and pro-oxidant-induced lipid peroxidation. The present result suggests the probable mediation of chemoprevention by ST against DEN-induced carcinogenesis by the modulation of drug metabolizing components in the liver of treated animals. [ABSTRACT FROM AUTHOR]

Abstract: The involvement of oxidative stress in the pathogenesis of hepatitis and hepatocellular carcinoma has been strongly suggested. Oxidative stress is produced by inflammatory processes that occur in hepatitis via immunological mechanisms. In addition, in hepatitis C virus (HCV) infectious disease, some role has been assigned to viral proteins in the induction of oxidative stress. In the presence of hepatic steatosis, insulin resistance and increased levels of some cytokines, all of which are also induced by viral protein expression, oxidative stress is enhanced in HCV infection. In this sense, the role of oxidative stress in the progression of chronic hepatitis and hepatocarcinogenesis is greater in hepatitis C than in other types of hepatitis such as hepatitis B or autoimmune hepatitis. The additive effects of oxidative stress caused by the inflammatory process and that induced by HCV proteins may, furthermore, exert synergistic effects with alterations in intracellular signaling systems such as mitogen-activated protein kinases (MAPK), which are also induced by HCV proteins. These synergistic effects may be responsible for rare characteristics, that is, the high incidence and multicentric nature of hepatocarcinogenesis in HCV infection. [Copyright &y& Elsevier]

Abstract: In addition to the link with development of hepatocellular carcinoma (HCC), hepatitis C virus (HCV) infection is associated with several extrahepatic manifestations such as essential mixed cryoglobulinemia, porphyria cutanea tarda or Sjögren''s syndrome. A role of hepatic steatosis in the pathogenesis of chronic hepatitis C has also been known, implying hepatitis C as a metabolic disease. In addition, recent epidemiological studies have suggested a linkage between type 2 diabetes and chronic HCV infection. However, the presence of additional factors in patients, such as obesity, aging or cirrhosis, prevents the establishment of a definite relationship between HCV infection and these two conditions, lipid metabolism disturbance and diabetes. In addition to the data indicating the presence of dyslipidemia and diabetes or insulin resistance in our cohort of chronic hepatitis C patients, we found a series of evidence showing the association between the conditions and HCV infection in mouse models that are transgenic for the HCV genes. In patients with chronic hepatitis C, a significant decrease in the serum levels of total cholesterol and apolipoproteins C2 and C3 was observed compared to those with chronic hepatitis B that were comparable in liver function. In an animal model, C18:1 mono-unsaturated fatty acids were significantly increased in the liver from HCV core gene transgenic mice, which was similarly observed in the liver from human hepatitis C patients. Thus, a disturbance in lipid metabolism was observed in both humans and an HCV mouse model, supporting that it is a specific event in HCV infection. A significant increase in the value of an indicator for homeostasis model assessment of insulin resistance (HOMA-IR), was observed in patients with chronic hepatitis C, even at the very early stage of chronic hepatitis. In the animal model, a marked insulin resistance was exhibited from a very young age in HCV core gene transgenic mice. Insulin resistance observed in the core gene transgenic mice was chiefly due to the shortage of insulin action on the suppression of glucose production in the liver. Thus, the ability of insulin to lower the plasma glucose level in the HCV transgenic mice was impaired, as observed in chronic hepatitis C patients. These results provide a direct experimental evidence for the contribution of HCV in the development of insulin resistance in human HCV infection, which finally leads to the development of type 2 diabetes. Insulin resistance may be a critical factor in the pathogenesis of chronic hepatitis C as recently suggested in non-alcoholic steatohepatitis (NASH), along with impairment in lipid metabolism. Our results would provide a clue for further understanding of pathobiology of HCV infection, and may provide an implication for the pathogenesis of NASH. [Copyright &y& Elsevier]

Liver cirrhosis accompanies at least 70% of hepatocellular carcinomas world-wide. To evaluate the dysregulation of apoptosis and the MAPK pathway in hepatocarcinogenesis, we investigated the expression profiles of the genes involved in apoptosis and MAPK pathway in cirrhosis and hepatocellular carcinoma. A total of 94 tissue specimens (61 cirrhosis and 33 hepatocellular carcinoma) obtained from 67 patients were analyzed by microarray, quantitative PCR and Western blot experiments.Of 71 apoptosis-associated genes, c-raf-1 and S6 were up-regulated in 42.9% and 32.1% of 28 cirrhosis tissues, respectively, and both genes were well correlated in a five-cluster K-means analysis. For c-raf-1 and down stream genes in the MAPK pathway, c-raf-1, MEK, and MAPK were up-regulated in 40%, 80%, and 86.7% of 45 cirrhosis specimens, respectively, and in 50%, 63.6%, and 59.1% of 22 hepatocellular carcinoma specimens, respectively. Western blot analysis showed that activated Raf-1 was over-expressed in 91.2% (52/57) of cirrhosis and in 100% (30/30) of hepatocellular carcinoma. The expression level of Raf-1 in 14 of 26 paired samples (53.8%) was significantly higher in hepatocellular carcinoma than in cirrhosis (16.2±20.3-fold, P<0.05). These results suggest that the activation of Raf-1 plays an important role in the development of hepatocellular carcinoma. [Copyright &y& Elsevier]

The aim of this study was to estimate the correlation between telomerase activity and the expression of human telomerase RNA component (hTERC), human telomerase reverse transcriptase (hTERT) in patients with hepatocellular carcinoma (HCC), and to analyze the influence of the nucleotide homology of the hTERC template region on telomerase activity. Six HCC patients and two chronic hepatitis patients were enrolled in this study. Telomerase activity was determined using the fluorescence-based telomeric repeat amplification protocol (TRAP) method. Quantification of hTERC and hTERTmRNA was performed using a real-time PCR method. Furthermore, a portion of the hTERC gene was amplified using nested RT-PCR methods. After sub-cloning, the nucleotide sequence of the cloned hTERC that contained the template region was determined. Telomerase activity and hTERTmRNA was detected in all cancerous tissues, while hTERC was present in both tumorous and non-tumorous lesions. The level of telomerase activity correlated with expression of hTERTmRNA, but not that of hTERC. The nucleotide sequence of cloned hTERC was similar in both tumorous and non-tumorous lesions. The expression of hTERT may be a definitive factor in the activation of telomerase in hepatocarcinogenesis. [Copyright &y& Elsevier]

In a rat model of hepatocarcinogenesis induced by a choline-deficient, l-amino acid-defined (CDAA) diet, hepatocellular carcinoma (HCC) occurs in conjunction with fatty liver, hepatocyte injury and regeneration, fibrosis and cirrhosis. This is similar to human HCC development with cirrhosis. The aim of this study is to clarify sequential changes in the expression of growth and growth inhibitory factors, and hepatocyte proliferation and apoptosis during development of preneoplastic nodules in rats fed a CDAA diet. The expression of hepatocyte growth factor was stimulated at about the same time as CDAA diet-induced liver injury within 1 week. Hepatocyte growth factor reached a maximum level of expression from 4 to 8 weeks. Transforming growth factor (TGF)-α expression increased from 4 to 40 weeks. Although TGF-β, a growth inhibitory factor for hepatocytes, was also expressed with a peak from 4 to 8 weeks followed by a gradual decrease until 48 weeks, expression of cyclin D1 and hepatocyte proliferation continued to be stimulated throughout the experimental period. Additionally, the number of apoptotic hepatocytes was markedly reduced after peaking at 8 weeks. These results suggest that some hepatocytes in the livers of rats fed a CDAA diet may escape from TGF-β-induced growth inhibition and apoptosis, leading to development of preneoplastic nodules. [Copyright &y& Elsevier]

Risk factors for the development of hepatocellular carcinoma (HCC) were investigated in 397 patients who underwent non-shunt operation for esophageal varices due to underlying cirrhosis or pre-cirrhosis between September 1979 and May 1995. Ninety-five of these patients developed HCC. The clinical characteristics of patients at the time of surgery for varices, stages (F0–F4) of the progression of fibrosis, and grades (A0–A3) of necroinflammatory activity in liver biopsy tissue obtained at surgery in 170 patients based on the New Inuyama Classification (Int. Hepatol. Commun. 6 (1996) 112) , were analyzed to investigate their relationship with the development of HCC. In addition, the levels of AST and ALT were followed every 3 months after surgery in 116 patients, and were divided into 2 groups at 80 IU/ml to compare the level of risk for the development of HCC. In liver biopsy tissue, group F4 (n=68/152, 45%) showed a significantly higher (P=0.0224) rate of appearance of HCC than group F3 (n=3/18, 17%). Group F4 also tended to show a higher cumulative HCC appearance rate of 55% compared with 37% for group F3 at 10 years after surgery (P=0.097). In regard to activity, the appearance rate of HCC in group A2+A3 (n=52/112, 51%) was significantly higher (P=0.0008) than that of HCC in group A1 (n=14/58, 25%). The cumulative appearance rate (60%) of HCC in group A2+A3 was significantly higher than that (31%) in group A1 at 10 years after surgery (P=0.0003). The appearance rate of HCC was significantly higher in the group (n=33/44, 75%) with a mean AST level &ges;80 IU/ml than in the group (n=41/72, 57%) with a mean AST level <80 IU/ml (P=0.0496). A multivariate analysis of the risk factors for the development of HCC showed that necroinflammatory activity was a risk factor. These results suggested that the histopathologic classification (the New Inuyama Classification) of liver biopsy tissue from patients who underwent non-shunt operation for esophageal varices due to underlying cirrhosis or pre-cirrhosis is useful for predicting the development of HCC, to which the grades of necroinflammatory activity in particular are more closely related. [Copyright &y& Elsevier]

P-glycoprotein (P-GP) is known to be a multidrug resistant 1 gene product and to exhibit resistance to a broad range of drugs including anticancer drugs such as epirubicin. Its overexpression is reported in human hepatocellular carcinoma and in adenomatous hyperplasia of the liver as well. In order to clarify the evolution of P-GP expression during hepatocarcinogenesis and its modulation by anticancer drugs, we performed an immunohistochemical study in male Wistar rat livers exposed to diethylnitrosamine (DEN) for 12 weeks. Some rats were pretreated with cisplatin or epirubicin 1 week prior to the exposure, and some rats were treated with them at the 10th week after the exposure. While there was no P-GP expression in the liver of the control, cisplatin, and epirubicin (DEN-free) rats, expression was confirmed in the hepatocytes of DEN-treated rats. The immunostaining of hyperplastic nodules was significantly more intense than in well-differentiated hepatocellular carcinomas, and no staining was observed in poorly-differentiated carcinomas. Markedly intense staining was observed in the early hyperplastic nodules of cisplatin-pretreated rats, as well as in epirubicin-pretreated rats. Plasma α-fetoprotein levels were markedly elevated in DEN-treated rats, while tumor necrosis factor-α levels were not. In conclusion, the results suggest that P-GP confers a protective effect against anticancer drugs and provides a great advantage to the initiated cells. Furthermore, in addition to epirubicin, cisplatin also promotes the induction of P-GP in the initiated cell. [ABSTRACT FROM AUTHOR]