Analysis of proliferating hepatocytes using a monoclonal antibody against proliferating cell nuclear antigen/cyclin in embedded tissues from various liver diseases fixed in formaldehyde.

The authors studied histochemically the morphologic features of proliferating hepatocytes positive for proliferating cell nuclear antigen (PCNA/cyclin) to analyze the process of liver regeneration in embedded tissues fixed with formaldehyde using an anti-PCNA/cyclin monoclonal antibody. In liver specimens from patients with acute viral hepatitis (AVH) and confluent necrosis, many small basophilic hepatocytes surrounding large clear hepatocytes were positively stained in the areas next to the confluent necrosis. Therefore these small hepatocytes may be daughter cells derived from large clear hepatocytes that probably enter the mitotic cell cycle repeatedly to repair a large necrotic area. In the case of AVH with spotty necrosis, the positively stained hepatocytes were scattered around the necrotic foci. In the liver specimens from patients with chronic active hepatitis, most of the positively stained hepatocytes were located next to the necrotic area. As for cirrhosis of the liver, the number of hepatocytes positive for PCNA/cyclin varied greatly in different pseudolobules, and in the specimens of hepatocellular carcinoma (HCC), the HCC cells positive for PCNA/cyclin were detected throughout the cancer nests.     

Looking for large-cell dysplasia in liver needle biopsies how and why?

Liver large cell dysplasia (LCD) is identifiable only at the microscopic level as foci of large hepatocytes with pleomorphic hyperchromatic nuclei and prominent nucleoli. LCD is mainly observed in cirrhotic livers, on surgical specimens, within macroregenerative nodules or low grade dysplastic nodules but also on liver needle biopsies. For needle biopsies, the prevalence of LCD ranges between 15% and 20%. in case of associated hepatocellular carcinoma, the prevalence is around 40%. LCD is more frequent in hepatitis B virus-induced liver cirrhosis than in cirrhosis related to other causes. Two prospective studies showed that LCD is a predictive factor for the occurrence of hepatocellular carcinoma in cirrhotic patients. Nevertheless LCD is probably not a precancerous lesion; dysplastic hepatocytes are biologically senescent polyploid cells unable to carry out normal cell division. Diagnosis of LCD on liver needle biopsy is indicative for the presence of large and numerous foci of LCD within the whole parenchya and allows consequently to select cirrhosis associated with advanced liver cell secescence, i.e. cirrhosis in which multistep genetic alterations of liver cell carcinogenesis could have happened with the greatest probability. Therefore pathologists have to identify and indicate the presence of LCD in the reports of liver needle biopsies     

Identification and fine structure of proliferating hepatocytes in malignant and nonmalignant liver diseases by use of a monoclonal antibody against DNA polymerase alpha

To analyze the process of liver regeneration and the initiation of hepatocellular carcinoma (HCC), we studied histochemically the morphologic features of proliferating parenchymal cells stained for DNA polymerase alpha (DPA), in 31 patients with various diseases, by use of a monoclonal antibody against DPA. In specimens from patients with acute viral hepatitis with confluent necrosis, most stained hepatocytes were small, with basophilic cytoplasm, and were located next to the necrotic areas. Under electron microscopy, stained granules were seen in the nucleus. Most stained hepatocytes had immature organelles. In specimens from patients with cirrhosis of the liver, the number of stained hepatocytes greatly differed in different pseudolobules. In specimens from patients with adenomatous hyperplasia, stained hepatocytes, mostly small and basophilic, were found diffusely; electron microscopy showed slightly indented nuclei with a few organelles and less condensed chromatin than normal. In specimens from patients with HCC, most stained cancer cells were small and basophilic; electron microscopy showed indented nuclei with a few organelles and less than normal condensed chromatin. Staining showed that during regeneration, immature hepatocytes reentered the cell cycle and repaired a large necrotic area. It was conceivable that in the initiation of HCC, some small hepatocytes with indented nuclei and less condensed chromatin might become HCC cells.     

In-vitro cell-mediated cytotoxicity for autologous liver cells in chronic non-A, non-B hepatitis.

To investigate the possible mechanisms of liver cell injury in chronic non-A, non-B (NANB) hepatitis, peripheral blood lymphocytes (PBL) from 16 patients with chronic NANB hepatitis were incubated with autologous hepatocytes in a microcytotoxicity assay. Significant cytotoxicity was demonstrated in 11 patients. T-enriched lymphocytes exhibited significantly greater cytotoxicity than non-T enriched cells. No significant inhibition of cytotoxicity was observed following preincubation of the liver cells with either monoclonal or polyclonal anti-HBc, or monoclonal anti-HBs, or addition of either purified HBsAg or recombinant HBcAg to the culture, indicating that there was no detectable cross-reactivity in this system between hepatitis B virus (HBV) and NANB-associated antigen(s). Preincubation of the patients' hepatocytes with polyclonal IgG purified from a serum of a patient who recovered from an acute NANB hepatitis, did not significantly alter cytotoxicity. Liver cell surface-bound IgG was detected by immunofluorescence in only two of the patients, a finding consistent with existing evidence of poor antibody responses to both liver membrane and NANB-associated antigens. Control experiments using PBL from allogeneic normal donors exhibited normal cytotoxicity for the patients' hepatocytes supporting the hypothesis that antibody-dependent cell-mediated cytotoxicity (ADCC) is unlikely to play a significant role in this clinical setting.     

Morphometric study of hepatocytes containing hepatitis B surface antigen

The development of hepatocellular carcinoma (HCC) is probably related to infection with hepatitis B virus (HBV). Hepatocytes in livers of patients with HCC have been reported to show putative preneoplastic changes such as hyperplasia, dysplasia, or adenomatous regeneration. To determine quantitatively whether these morphologic changes are associated with HBV-infected cells, the authors performed morphometry of hepatitis B surface antigen (HBsAg)-positive hepatocytes in the nontumorous portion of 10 livers with HCC and in 10 livers without HCC. The diameter of nuclei and cytoplasm of HBsAg-positive hepatocytes was measured after demonstration of HBsAg by the peroxidase-antiperoxidase method. As controls, HBsAg-negative hepatocytes in the same liver sections were measured as well as hepatocytes of 20 age-matched HBsAg-negative patients with normal liver or alcoholic cirrhosis. HBsAg-positive hepatocytes exhibited significantly larger nuclei and a higher nucleocytoplasmic ratio than control hepatocytes. In addition, HBsAg-positive cells were often arranged in foci that consisted of two cell populations: hypertrophic (enlarged nuclei and nucleocytoplasmic ratio) and hyperplastic (two-cell-thick plates of small cells with a high nucleocytoplasmic ratio). While precancerous cells have been difficult to identify, these morphologic changes are frequently associated with the development of malignant neoplasia.     

Regenerative pattern of liver cells in primary biliary cirrhosis, alcoholic cirrhosis, posthepatitic cirrhosis (HBV-related) and hepatocellular carcinoma: Comparative analysis by computerized morphometry

Computerized morphometrical measurements were made of liver cells and their nuclei taken from biopsy specimens of primary biliary cirrhosis (PBC), alcoholic cirrhosis, posthepatttic cirrhosis (HBV-related), and hepatocellular carcinoma (HCC). The specimens were stained with hematoxylln-eosin (HE), Mallory's stain for collagen fibers, orcein method, periodic acid Schiff (PAS) reaction, and silver impregnation. Light microscopic views were then selected and original liver cells were magnified × 1000. The size of liver cell nuclei, distance between corresponding liver cell nuclei and distribution pattern of hepatocytes were calculated by computer. Variation in regenerative activity among the four disease groups was noted. Regenerative features of liver cells were mild in degree in PBC. In alcoholic cirrhosis, regenerative features of liver cells were less prominent than in posthepatitic cirrhosis. In posthepatitic cirrhosis, regenerative liver cells were well developed, showing remarkable pleomorphlsm of liver cell nuclei and expansive arrangement of liver cell cords. This tendency towards regenerative activity suggests that the possibility of HCC occurring Is greater In posthepatitic cirrhosis than in PBC or alcoholic cirrhosis. It was concluded that morphologically, there is a greater possibility of occurrence of HCC in posthepatitic cirrhosis than in any other type of cirrhosis, because of its high regenerative hepatocytic activity. Also etiological factors of liver diseases are more important in the developement of liver cell regeneration. Furthermore, regenerative activity can be measured by computerized morphometry as an established methodology.     

c－erbB－2蛋白和表皮生长因子受体在肝脏病变中的表达

对１８４例乙型肝炎、肝硬变和肝细胞癌（ＨＣＣ）及２９例正常肝组织的标本作了ＡＢＣ法染色，观察其ｃ－ｅｒｂＢ－２蛋白和表皮生长因子受体（ＥＧＦＲ）的表达情况。３６％（４８／１３４）的慢性肝炎、肝硬变和ＨＣＣ组织中有ＥＧＦＲ表达，主要定位于血窦内皮。良、恶性病变肝组织之间在ＥＧＦＲ表达强度上无显著差别，提示ＥＧＦＲ可能与慢性肝脏病变中血窦内皮的增生有关。在正常肝，仅少数标本（５／２９）中见到ｃ－ｅｒｂＢ－２微弱表达；在ＨＢＶ相关的慢性肝脏病变，所有标本中均检测到ｃ－ｅｒｂＢ－２蛋白，主要定位于肝小多角细胞（ＳＰＬＣ）、小细胞性不典型增生（ＳＣＤ）及小管状化生（ＤＭ）的肝细胞；ＨＣＣ细胞中ｃ－ｅｒｂＢ－２蛋白阳性较弱。这提示ｃ－ｅｒｂＢ－２基因的活化与人ＨＣＣ发生有关。其作用机制可能是促进ＳＰＬＣ向ＳＣＤ的转化及促进ＳＣＤ的进展。ｃ－ｅｒｂＢ－２与ＨＢｘＡｇ表达的密切关联提示这种原癌基因的活化可能也与ＨＢＶＸ基因有关。     

Liver cell dysplasia and hepatocellular carcinoma: a histoiogical and immunohistochemical study

Liver cell dysplasia (LCD) was found in 28 (60%) of 47 patients with hepatocellular carcinoma (HCC); 22 (79%) of them had associated liver cirrhosis. LCD was more frequently observed in posthepatitic cirrhosis (82%) than in the other forms. Carcinoembryonic antigen (CEA), alpha-1-antitrypsin (AAT) and alpha-fetoprotein (AFP), as demonstrated by the peroxidase-antiperoxidase method, were similarly expressed both in normal and in dysplastic cells. Hepatitis B surface antigen was found in eight cases (17%), six of which were associated with LCD. HBsAg was rarely found in dysplastic cells and frequently displayed a peculiar perinuclear pattern. The possible preneoplastic role of LCD is stressed.     

Evolution of hepatocellular carcinoma associated with chronic hepatitis B virus infection in Alaskan Eskimos

Hepatocellular carcinoma (HCC) associated with chronic hepatitis B virus (HBV) infection in Yupik Eskimos in southwestern Alaska, detected in early stages as a result of screening, appears to be more frequently associated with variants of chronic portal inflammation in the noninvolved liver than with fully developed cirrhosis, otherwise common in HBV-associated HCC from other geographic areas. Of 38 patients diagnosed with HCC since 1969, adequate tissue was available from both the tumor and nontumorous liver in 17. Of the 17 specimens, 14 had chronic portal inflammation and three had advanced cirrhosis; 12 of the 14 were from hepatitis B surface antigen carriers. These 12 cases were studied in detail to examine the features accompanying the development of HCC unobscured by cirrhotic transformation. In the noninvolved parenchyma they included hepatocytic nodules as apparent precursors to HCC and, as markers of phenotypic alterations, dysplastic hepatocytes and hepatitis B surface antigen-laden ground-glass hepatocytes. The latter were observed in eight instances and often accumulated in nodules. Parenchyma within 1 mm of the HCC exhibited increased confluent hyperplasia and frequently conspicuous necroinflammation associated with pericellular and periductular fibrosis, which contributed, in addition to fibrous connections between displaced and heavily inflamed portal tracts, to the capsule that was forming in all cases to varying degrees in the pericarcinomatous region. The HCC was uniformly trabecular and in a few specimens, a continuous transition from hyperplasia and dysplasia near the periphery of the tumor to increasing anaplasia in the center could be made out in addition to pressure effects of the HCC. The pericarcinomatous changes, including hyperplasia progressing to neoplasia and necroinflammation, are also observed in experimental models, particularly the woodchuck HCC induced by a hepadna virus related to HBV. Coordinated morphologic and molecular biologic studies on such animal models and on human HCC detected by screening, as for instance in Eskimos, neither complicated by cirrhosis, should elucidate the direction of the evolution of the HCC and the postulated promoting role of the inflammation.     

NK cells in hepatitis B virus infection: a potent target for immunotherapy

Viruses, including hepatitis B virus (HBV), are the most prevalent and infectious agents that lead to liver disease in humans. Hepatocellular carcinoma (HCC) and cirrhosis of the liver are the most serious complications arising from prolonged forms of hepatitis B. Previous studies demonstrated that patients suffering from long-term HBV infections are unable to eradicate HBV from hepatocytes completely. The mechanisms responsible for progression of these forms of infection have not yet been clarified. However, it seems that there are differences in genetic and immunological parameters when comparing patients to subjects who successfully clear HBV infections, and these may represent the causes of long-term infection. Natural killer (NK) cells, the main innate immune cells that target viral infections, play important roles in the eradication of HBV from hepatocytes. NK cells carry several stimulatory and inhibitor receptors, and binding of receptors with their ligands results in activation and suppression of NK cells, respectively. The aim of this review is to address the recent information regarding NK cell phenotype, functions and modifications in hepatitis B. This review addresses the recent data regarding the roles of NK cells as novel targets for immunotherapies that target hepatitis B infection. It also discusses the potential to reduce the risk of HCC or cirrhosis of the liver by targeting NK cells.     

Orcein-positive hepatitis B surface antigen and liver carcinoma: their association in an Eastern US population

We retrospectively examined the association of hepatitis B infection and hepatocellular carcinoma (HCC) in a US East Coast population using orcein staining of fixed liver tissue. Hepatitis B surface antigen (HBsAg) was present in non-neoplastic hepatocytes in eight of 53 cases of HCC, but in no cases of cholangiocarcinoma or metastatic tumor. In five of the eight positive cases, macronodular cirrhosis was present; in three positive cases, cirrhosis was absent. The rate of positivity in livers with both HCC and macronodular cirrhosis was 28%, compared with 4.7% in livers with macronodular cirrhosis but no carcinoma. The low, but significant association of HBsAg and HCC, both in the presence and absence of cirrhosis, suggests that HCC may develop in a subset of patients in the United States as a result of infection with hepatitis B virus.     

Impact of epidermal growth factor receptor and transforming growth factor–α on hepatitis C virus‐induced hepatocarcinogenesis

Epidermal growth factor receptor system plays a central hepato‐protective and pro‐regenerative role in liver. Transforming growth factor‐α (TGF‐α) is an important autocrine growth regulator of hepatocytes that plays a role in development of hepatocellular carcinoma (HCC) among patients with chronic hepatitis C (CHC). This study was done on 40 core liver biopsies from patients with CHC, 20 liver specimens from HCC cases on top of CHC as well as five normal controls. All were immunohistochemically stained with epidermal growth factor receptor (EGFR) and TGF‐α antibodies. Some selected HCC cases were submitted for FISH technique to detect EGFR gene alteration. By immunohistochemistry EGFR and TGF‐α were overexpressed in HCC and cirrhotic cases compared to CHC cases without cirrhosis. Also, their expression was stronger in CHC cases with higher grades of activity and stages of fibrosis compared to lower ones. FISH positive results for EGFR were detected in 33.3% of the examined HCC cases. EGFR and TGF‐α can be used as predictive markers for activity, fibrosis, and carcinogenesis in CHC patients. Overexpression of EGFR in HCC patients can be promising in selecting those who can get benefit from anti‐EGFR target therapy.     

Studies on the mechanism of elevation of serum PIVKA-II levels in alcoholic liver cirrhosis

We measured serum PIVKA-II concentrations in 18 patients with alcoholic liver cirrhosis. Alcoholic liver disease was diagnosed by the history of ethanol intake of more than 900 ml/day for over 10 years. Liver cirrhosis was diagnosed histologically. Infections with hepatitis B and C viruses were ruled out by assaying serum virus markers. No tumor was detected in liver by ultrasonography and computed tomography during observation period. None of the patients studied were positive for alpafetoprotein (AFP). Eight out of 18 (44.4%) patients with alcoholic liver cirrhosis showed elevated serum PIVKA-II levels. In contrast, only eight out of 93 (8.6%) patients with nonalcholic liver cirrhosis had elevated serum PIVKA-II levels. PIVKA-II is well known as a tumor marker of hepatocellular carcinoma (HCC). The rates of positive PIVKA-II found in alcoholic liver cirrhosis approached its rates in HCC. However, the time course for the elevation of serum PIVKA-II levels was different each other in alcoholic liver cirrhosis and HCC. In HCC, serum PIVKA-II "levels" continued to elevate until therapy. In contrast, its elevation was transient and its levels returned to baseline in alcoholic liver cirrhosis. The values of ALT (GPT), gamma-GTP, and ALP correlated poorly with serum PIVKA-II levels in patients with alcoholic liver cirrhosis. To investigate the mechanism by which elevation of serum PIVKA-II levels in patients with alcoholic liver cirrhosis occurred, we studied the effect of vitamin K on production of PIVKA-II and AFP by hepatocytes. Hepatocytes(Alexander PLC/PRF/F cell line) were cultured in the presence of various concentrations of vitamin K (Kaytwo, Eisai, Tokyo). Vitamin K had no effect on AFP production. In contrast, PIVKA-II production was inhibited by addition of vitamin K in a dose dependent manner. Moreover, elevation of serum PIVKA-II levels in patients with alcoholic liver cirrhosis was suppressed by administration of vitamin K (Kaytwo) to these patients. Taken together, these results suggest that vitamin K may have a role in the mechanism of PIVKA-II elevation in sera of these patients. Then, we measured serum concentrations of vitamin K(PK, MK-4, MK-7) in these patients. There was no correlation observed between vitamin K and PIVKA-II in these patients. This result suggests that elevation of serum PIVKA-II in these patients may not be due to vitamin K deficiency. One question not answered here is how serum PIVKA-II levels in these patients are suppressed by treatment with vitamin K (Kaytwo). More detailed analysis of the mechanism of elevation of serum PIVKA-II levels in patients with alcoholic liver cirrhosis is needed.     

Human binucleate hepatocytes: Are they a defence during chronic liver diseases?

Binucleate cells are commonly found in various human organs including liver, salivary glands and endometrium, but their functional advantage remains unknown. The increased occurrence of binucleate hepatocytes during the necro-inflammation stage of progressive chronic hepatitis and its end-stage of cirrhosis, but their absence in hepatocellular carcinoma (HCC), has led us to hypothesise that they may be an index of the severity of hepatic illness rather than the result of errors occurring during the course of the cell cycle. This hypothesis is supported by the immunohistochemical analysis of retinol-binding protein expression, and the different life cycles of hepatitis B virus in mononucleate and binucleate hepatocytes. If founded, this hypothesis would add to our understanding of the relationship between binucleate hepatocytes and the evolution of chronic liver disease, and promises the ideation of new criteria for identifying potential HCC patients.     

Significance of pSmad2/3 and Smad4 in hepatitis C virus‐related liver fibrosis and hepatocellular carcinoma

Chronic hepatitis C (CHC) is a major public health problem, especially in Egypt. Risk of hepatocellular carcinoma (HCC) development increases as hepatitis C virus (HCV)‐related liver diseases progress. Smads act as substrates for the transforming growth factor‐beta (TGF‐β) family of receptors. This study aims to assess hepatic expression of pSmad2/3 and Smad4 in CHC with different stages of fibrosis and grades of necro‐inflammation as well as in HCC on top of CHC. This study was done on 33 core liver biopsies from patients with CHC (15 with early fibrosis and 18 with late fibrosis), 15 liver specimens from HCC cases on top of CHC, as well as five normal controls. pSmad2/3 and Smad4 show more immunopositivity, higher percentage of positive hepatocytes and stronger staining intensity in CHC with late fibrosis compared to early fibrosis. pSmad2/3 shows increase of the previous parameters in CHC with high grade activity than those with low activity. Smad4 shows increase of the previous parameters in HCC compared to CHC cases. pSmad2/3 and Smad4 can be used as diagnostic and/or prognostic markers for progression of HCV‐related fibrosis to cirrhosis and further progression to HCC.     

Detection of a liver-membrane autoantibody in HBsAg-negative chronic active hepatitis.

Investigation of humoral immunity against hepatocellular membrane antigens in patients with chronic active hepatitis and other liver diseases showed two different immunofluorescence patterns of IgG on hepatocyte membranes. A linear pattern was seen in HBsAg-negative hepatitis, but HBsAg-positive cases and some of protracted, acute hepatitis B had a granular pattern. In patients with IgG bound to hepatocytes, continuing necrosis of parenchymal liver cells was seen. Conversely, hepatocytes without bound IgG were found in cases of chronic active hepatitis in remission, acute viral hepatitis without HBsAg and chronic persistent hepatitis, in "healthy" HBsAg-carriers and in patients with fatty liver or alcoholic cirrhosis. A liver-membrane autoantibody in serum, proved by fixation on membranes of isolated rabbit hepatocytes, could be demonstrated only in HBsAg-negative chronic active hepatitis with elevated IgG-concentrations. The results support the existence of different pathogenetic types of chronic active hepatitis, a so-called autoimmune type and a hepatitis virus-B-induced type.     

Non-B hepatocellular carcinoma: influence of age, sex, alcohol, family clustering, blood transfusion and chronic liver disease

In 144 cases of hepatocellular carcinoma (HCC), 166 cases of cirrhosis without HCC and 142 cases of chronic hepatitis, we examined HBsAg, anti-HBs and anti-HBc in sera and compared the following factors between hepatitis B virus marker-negative and -positive patients: age, sex, alcohol consumption, family clustering of liver diseases, and histories of blood transfusion and post-transfusion hepatitis. Results of this study demonstrated several distinct differences in clinical backgrounds between non-B (negative for HBsAg, anti-HBs and anti-HBc) and B (positive for HBsAg) patients with HCC. Non-B patients were significantly older, had a lower frequency of familial tendencies for liver diseases, and more frequently had cancers other than HCC in their families. Some of these differences were also observed between non-B and B patients with cirrhosis and chronic hepatitis. Among patients with chronic hepatitis, the non-B patients had received blood transfusion or had post-transfusion hepatitis more frequently than the B patients. However, this difference was not apparent in patients with liver cirrhosis or HCC, suggesting that progression of non-A, non-B post-transfusion hepatitis to cirrhosis and HCC may not be as frequent as progression to chronic hepatitis.     

Detection of micronuclei formation and nuclear anomalies in regenerative nodules of human cirrhotic livers and relationship to hepatocellular carcinoma

Human cirrhosis is considered an important factor in hepatocarcinogenesis. The lack of substantial genetics and cytogenetics data in human cirrhosis led us to investigate spontaneous micronuclei formation, as an indicator of chromosomal damage. The analysis was performed in hepatocytes of regenerative, macroregenerative, and tumoral nodules from 30 cases of cirrhosis (paraffin-embedded archival material), retrospectively selected: cryptogenic, hepatitis C virus, and hepatitis C virus associated with hepatocellular carcinoma (HCC). Thirteen control liver samples of healthy organ donors were included. Micronucleated hepatocytes were analyzed with Feulgen-fast-green dyeing techniques. The spontaneous frequency of micronucleated hepatocytes in both regenerative and macroregenerative nodules of all cirrhotic patients was significantly higher than for the normal control group. There was no significant difference in frequency of micronucleated hepatocytes in regenerative nodules compared with macroregenerative nodules for all cases analyzed, whereas a significantly higher frequency of micronucleated hepatocytes was detected in tumoral nodules, compared with cirrhotic regenerative nodules and normal parenchyma. A higher frequency of the nuclear anomalies termed broken-eggs was observed in hepatitis C virus-related samples. Chromatinic losses and genotoxicity already existed in the cirrhotic regenerative nodules, which might predispose to development of HCC.     

Prevalence of a non-A, non-B-associated antigen/antibody system detected by radioimmunoassay in acute and chronic liver disease

An antigen/antibody system associated with one form of parenterally transmitted non-A, non-B (NANB) hepatitis has been identified by solid-phase radioimmunoassay (RIA). The antigen is found in 3% of normal subjects and in increased frequency in patients with haemophilia, renal homograft recipients, homosexual men, prostitutes, drug addicts, and patients with chronic hepatitis B virus (HBV) infection. The antigen was found in normal frequency in patients with acute hepatitis A and B, sporadic NANB hepatitis (nondrug addicts), autoimmune and alcohol-induced chronic liver disease, and primary biliary cirrhosis.