Application of Immunohistochemistry in the Pathological Diagnosis of Liver Tumors.

Although radiological diagnostics have been progressing, pathological diagnosis remains the most reliable method for diagnosing liver tumors. In some cases, definite pathological diagnosis cannot be obtained by histological evaluation alone, especially when the sample is a small biopsy; in such cases, immunohistochemical staining is very useful. Immunohistochemistry is the most frequently used technique for molecular pathological diagnosis due to its broad application, ease of performance and evaluation, and reasonable cost. The results occasionally reflect specific genetic mutations. The immunohistochemical markers of hepatocellular carcinoma include those of hepatocellular differentiation-such as hepatocyte paraffin 1 and arginase-1-and those of malignant hepatocytes-such as glypican-3, heat shock protein 70, and glutamine synthetase (GS). To classify the subtypes of hepatocellular adenoma, examination of several immunohistochemical markers, such as liver fatty acid-binding protein, GS, and serum amyloid A, is indispensable. Immunohistochemical staining for GS is also important for the diagnosis of focal nodular hyperplasia. The representative immunohistochemical markers of intrahepatic cholangiocarcinoma include cytokeratin (CK) 7 and CK19. In this article, we provide an overview of the application of immunohistochemistry in the pathological diagnosis of liver tumors referring to the association with genetic alterations. Furthermore, we aimed to explain the practical points in the differential diagnosis of liver tumors by immunohistochemical staining.

[A Case of Transverse Colon Cancer with Liver Metastasis and Tumor Thrombosis of Portal Vein Effectively Treated with Chemotherapy].

The patient was a 70-year-old man. He was diagnosed with advanced transverse colon cancer. A computed tomography (CT)revealed liver metastasis and tumor thrombosis of portal vein. We started combination chemotherapy with capecita- bine/oxaliplatin(CapeOX). Perforation of the tumor was observed 5 days after CapeOX therapy was started. Treatment with abscess drainage and ileostmy, infection was controlled and general condition was improved. After 9 courses of CapeOX, we changed chemotherapy regimen to irinotecan/tegafur-gimeracil-oteracilpotassium (IRIS)due to strong side effects. In CT and FDG-PET examination after 8 courses of IRIS, the tumor of transverse colon, liver metastasis, and the tumor thrombosis of portalvein became unclear. A year and 6 months have passed since chemotherapy was started, recurrence was not observed. For the patients with unresectable colorectal cancer, it is necessary to consider multidisciplinary treatments including chemotherapy while considering the general condition of them.

[Four Cases of Occult Breast Cancer Treated with Breast Conserving Therapy after Neoadjuvant Chemotherapy].

We report 4 patients with occult breast cancer(OBC)who underwent breast conserving therapy(BCT)after neoadjuvant chemotherapy(NAC). All patients complained of axillary tumor and were diagnosed by core needle biopsy. Pathological examination of the axillary lymph nodes proved that 3 cases were adenocarcinomas and 1 case was squamous cell carcinoma, but imaging studies could not depict any primary lesions in the breast and other organs. Since distant metastasis was not observed, BCT with axillary lymph node dissection(ALND)was performed after NAC. All patients were undergoing whole breast irradiation. There were no residual cancer cells in the axillary lymph nodes in case 1 due to the treatment effect of NAC, but lymph node metastasis remained in other 3 cases. In the second case, she followed a rapid outcome, and pulmonary metastasis appeared in 7 months after surgery and died in 10 months. In the other 3 cases, there has not been found local and distant recurrence. Although OBC requires appropriate systemic treatment, present observation indicated that ALND with breast irradiation after NAC could be a useful option.

Preserved or enhanced OATP1B3 expression in hepatocellular adenoma subtypes with nuclear accumulation of ß-catenin.

AIM: Recent studies have indicated that hepatocellular adenoma (HCA) is a heterogenous group of benign tumors with various genetic and clinicopathological characteristics. We delineated the clinicopathological characteristics of HCA subtypes and evaluated the expression of transporter protein OATP1B3 in HCA. METHODS: HCA in 34 Japanese patients were investigated immunohistochemically and classified into four subtypes (HNF1α-inactivated type, H-HCA; ß-catenin-activated type, b-HCA; inflammatory type, I-HCA; unclassified type, u-HCA). Immunostaining of OATP1B3 protein in HCA tissue sections was performed to determine the association between OATP1B3 expression and HCA subtypes. RESULTS: HCA was categorized into the following four subtypes and two combined subtypes: 10 H-HCA (29%), 10 I-HCA (29%), seven b-HCA (21%), two b-HCA/H-HCA (6%), two b-HCA/I-HCA (6%) and three u-HCA (9%). The male-to-female ratio was 18:16. Oral contraceptive use was rare but seven HCA were found in patients with glycogen storage disease, congenital absence of the portal vein and idiopathic portal hypertension. OATP1B3 expression was decreased in 24 HCA but was preserved or increased in 10 HCA. All nine HCA with nuclear staining for ß-catenin showed preserved or enhanced OATP1B3 expression, indicating a significant association between nuclear ß-catenin accumulation and OATP1B3 expression in HCA. CONCLUSION: HCA subtype classification was validated in 91% of our Japanese subjects although their clinical backgrounds including rare contraceptive use were different from European subjects. A close association between preserved or enhanced OATP1B3 expression and b-HCA subtype indicated important modalities for clinical decisions in the treatment and follow up of patients with HCA.

Stromal miR-21 is more important than miR-21 of tumour cells for the progression of gastric cancer.

BACKGROUND: Gastric cancer (GC) is a common cancer globally. miRNA-21 (miR-21) appears to be important in the tumourigenesis of almost all types of human cancer. However its precise localization in GC has yet to be clarified. We thus examined miR-21 localization in GC and revealed its clinicopathological importance. METHODS: Tissue arrays of 469 GCs from 454 patients were examined for miR-21 using in situ hybridization (ISH). The positivity was evaluated separately in tumour cells and stromal cells. Conventional sections of 10 GCs were also stained. Eight cases were examined by quantitative RT-PCR (qRT-PCR). RESULTS: miR-21 was highly expressed in tumour cells of 44% of cases and in cancer stroma of 51% of cases. miR-21 of tumour cells was not related to clinicopathological factors, whereas stromal miR-21 was related to many factors including tumour stage, size, and nodal metastasis. Stromal miR-21 gradually increased during tumour progression. ISH of whole sections showed stronger stromal positivity in invasive areas with desmoplastic reaction. Cancer stroma also showed higher miR-21 expression than tumour and non-tumourous tissue in the qRT-PCR study. CONCLUSION: Stromal miR-21 is closely related to tumour progression in GC. Stromal miR-21 of tumours might be a target of treatment.

Integrins αvß6, α6ß4 and α3ß1 are down-regulated in cholangiolocellular carcinoma but not cholangiocarcinoma.

AIM: The aim of this study was to evaluate integrin expression and immunolocalization of the extracellular matrix proteins in cholangiolocellular carcinoma (CoCC). METHODS: Tissue specimens of 23 CoCC, 28 cholangiocarcinomas (CCC), 42 hepatocellular carcinomas (HCC) and 11 classical type combined hepatocellular cholangiocarcinomas (CHC) were immunostained for ß6, ß4 and α3 integrins, fibronectin and laminin. ITGB6, B4 and A3 mRNA levels in six HCC cell lines, five CCC cell lines and two CHC cell lines were quantified by quantitative reverse transcription polymerase chain reaction. RESULTS: Little or no positivity for ß6, ß4 and α3 integrins was shown in 91%, 91% and 52% of CoCC and 100%, 98% and 81% of HCC, respectively, according to immunostaining, whereas intense positive staining for these integrins was demonstrated in 64%, 96% and 75% of CCC, respectively. There was a close correlation between ß4 and α3 integrin expression and intracytoplasmic laminin in CoCC, CCC and HCC, but not between ß6 expression and its ligand, fibronectin. Integrin mRNA levels were increased in four of five CCC cell lines, but nearly undetectable in five of six HCC cell lines and one CHC cell line. Tubular differentiation of a CHC cell line cultured in collagen gel matrix induced upregulation of these integrins. CONCLUSION: Our results first indicated downregulation of αvß6, α6ß4 and α3ß1 integrins in CoCC, in contrast to its high expression in CCC, suggesting a diagnostic value of integrins in the differential diagnosis of CoCC and CCC, as well as a useful inducible marker of the intermediate features of CoCC.

Discrimination of fibrotic staging of chronic hepatitis C using multiple fibrotic markers.

AIM: In order to evaluate and judge a fibrotic stage of patients with chronic hepatitis C, multivariate regression analysis was performed using multiple fibrotic markers. METHODS: A total of 581 patients from eight hepatology units and institutes were diagnosed by needle biopsy as having chronic liver disease caused by hepatitis C virus. Twenty-three variables and their natural logarithmic transformation were employed in the multivariate analysis. RESULTS: Multivariate regression analysis finally obtained the following function: z = 2.89 × ln (type IV collagen 7S) (ng/mL) - 0.011 × (platelet count) (×10(3) /mm(3) ) + 0.79 × ln (total bilirubin) (mg/dL) + 0.39 × ln (hyaluronic acid) (µg/L) - 1.87. Median values of the fibrotic score of F1 (n = 172), F2 (n = 80), F3 (n = 37) and F4 (n = 16) were calculated as 1.00, 1.45, 2.82 and 3.83, respectively. Multiple regression coefficient and coefficient of determination were 0.56 and 0.320, respectively. Validation with patient data from other institutions demonstrated good reproducibility of the fibrotic score for hepatitis C (FSC), showing 1.10 in F1 (n = 156), 2.35 in F2 (n = 73), 3.16 in F3 (n = 36) and 3.58 in F4 (n = 11). CONCLUSION: A concise multiple regression function using four laboratory parameters successfully predicted pathological fibrotic stage of patients with hepatitis C virus infection.

Japanese herbal medicines shosaikoto, inchinkoto, and juzentaihoto inhibit high-fat diet-induced nonalcoholic steatohepatitis in db/db mice.

Few studies have investigated the effects of Japanese herbal medicines on nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH). To the best of our knowledge, only one study has examined whether high-fat (HF) diet-fed db/db mice are appropriate animal models of NASH. We investigated the effects of four types of Japanese herbal medicines (shosaikoto (TJ-9), inchinkoto (TJ-135), juzentaihoto (TJ-48), and keishibukuryogan (TJ-25)) on hepatic lesions of HF diet-fed db/db mice. Db/db mice were divided into six groups: control diet (control); HF diet (HF); and HF diet supplemented with TJ-9, TJ-135, TJ-48, or TJ-25 (TJ-9, TJ-135, TJ-48, and TJ-25, respectively). Mice were killed after 6 weeks of treatment, and biochemical and pathological analyses were performed. Mice in the HF group consistently developed histopathological features consistent with definite NASH, and marked necroinflammation occurred. Serum alanine aminotransferase levels in the TJ-9, TJ-135, and TJ-48 groups were significantly improved compared with those in the HF group. With regard to liver histology, TJ-9 and TJ-48 significantly improved lobular inflammation, and TJ-135 significantly improved ballooning degeneration. We have shown that HF diet-fed db/db mice are animal models that correctly recapitulate the histopathology of human NASH and that TJ-9, TJ-135, and TJ-48 inhibit necroinflammatory activity in this model.

Histone acetyltransferase Hbo1 destabilizes estrogen receptor α by ubiquitination and modulates proliferation of breast cancers.

The estrogen receptor (ER) is a key molecule for growth of breast cancers. It has been a successful target for treatment of breast cancers. Elucidation of the ER expression mechanism is of importance for designing therapeutics for ER-positive breast cancers. However, the detailed mechanism of ER stability is still unclear. Here, we report that histone acetyltransferase Hbo1 promotes destabilization of estrogen receptor α (ERα) in breast cancers through lysine 48-linked ubiquitination. The acetyltransferase activity of Hbo1 is linked to its activity for ERα ubiquitination. Depletion of Hbo1 and anti-estrogen treatment displayed a potent growth suppression of breast cancer cell line. Hbo1 modulated transcription by ERα. Mutually exclusive expression of Hbo1 and ERα was observed in roughly half of the human breast tumors examined in the present study. Modulation of ER stability by Hbo1 in breast cancers may provide a novel therapeutic possibility.

Fibrosis score consisting of four serum markers successfully predicts pathological fibrotic stages of chronic hepatitis B.

AIM: In order to evaluate and judge a fibrotic stage of patients with chronic hepatitis B, multivariate regression analysis was performed using multiple fibrosis markers. METHOD: A total of 227 patients from seven hepatology units and institutes were diagnosed by needle biopsy as having chronic liver disease caused by hepatitis B virus. Twenty-three variables and their natural logarithmic transformation were employed in the multivariate analysis. Multiple regression function was generated from data of 158 patients in one hospital, and validation was performed using the other data of 69 patients from six other hospitals. RESULTS: After stepwise variable selection, multivariate regression analysis finally obtained the following function: z = 1.40 × ln (type IV collagen 7S) (ng/mL) - 0.017 × (platelet count) (×1000(3) /mm(3) ) + 1.24 × ln (tissue inhibitor of matrix metalloproteinase-2) (ng/mL) + 1.19 × ln (α-2-macroglobulin) (mg/dL) - 9.15. Median values of fibrosis scores of F1 (n = 73), F2 (n = 42), F3 (n = 31) and F4 stages (n = 12) were calculated as 0.95, 2.07, 2.98 and 3.63, respectively. Multiple regression coefficient and coefficient of determination were 0.646 and 0.418, respectively. Validation with patient data from other institutions demonstrated good reproducibility of fibrosis score for hepatitis B (FSB), showing 1.33 in F1 (n = 27), 2.20 in F2 (n = 20), 3.11 in F3 (n = 20) and 5.30 in F4 (n = 2), respectively. CONCLUSION: A concise multiple regression function using four laboratory parameters successfully predicted pathological fibrosis stage of patients with hepatitis B virus infection.

Pathology and Pathogenesis of Metabolic Dysfunction-Associated Steatotic Liver Disease-Associated Hepatic Tumors.

Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive fat accumulation in the livers of patients without a history of alcohol abuse. It is classified as either simple steatosis (nonalcoholic fatty liver) or nonalcoholic steatohepatitis (NASH), which can progress to liver cirrhosis and hepatocellular carcinoma (HCC). Recently, it was suggested that the terms "metabolic dysfunction-associated steatotic liver disease (MASLD)" and "metabolic dysfunction-associated steatohepatitis (MASH)" should replace the terms "nonalcoholic fatty liver disease (NAFLD)" and "nonalcoholic steatohepatitis (NASH)", respectively, with small changes in the definitions. MASLD, a hepatic manifestation of metabolic syndrome, is rapidly increasing in incidence globally, and is becoming an increasingly important cause of HCC. Steatohepatitic HCC, a histological variant of HCC, is characterized by its morphological features resembling non-neoplastic steatohepatitis and is closely associated with underlying steatohepatitis and metabolic syndrome. Variations in genes including patatin-like phospholipase domain-containing protein 3 (PNPLA3), transmembrane 6 superfamily 2 (TM6SF2), and membrane-bound O-acyltransferase domain-containing protein 7 (MBOAT7) are associated with the natural history of MASLD, including HCC development. The mechanisms of HCC development in MASLD have not been fully elucidated; however, various factors, including lipotoxicity, inflammation, reactive oxygen species, insulin resistance, and alterations in the gut bacterial flora, are important in the pathogenesis of MASLD-associated HCC. Obesity and MASLD are also recognized as risk factors for hepatocellular adenomas, and recent meta-analyses have shown an association between MASLD and intrahepatic cholangiocarcinoma. In this review, we outline the pathology and pathogenesis of MASLD-associated liver tumors.

Artificial intelligence and deep learning: New tools for histopathological diagnosis of nonalcoholic fatty liver disease/nonalcoholic steatohepatitis.

Nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) is associated with metabolic syndrome and is rapidly increasing globally with the increased prevalence of obesity. Although noninvasive diagnosis of NAFLD/NASH has progressed, pathological evaluation of liver biopsy specimens remains the gold standard for diagnosing NAFLD/NASH. However, the pathological diagnosis of NAFLD/NASH relies on the subjective judgment of the pathologist, resulting in non-negligible interobserver variations. Artificial intelligence (AI) is an emerging tool in pathology to assist diagnoses with high objectivity and accuracy. An increasing number of studies have reported the usefulness of AI in the pathological diagnosis of NAFLD/NASH, and our group has already used it in animal experiments. In this minireview, we first outline the histopathological characteristics of NAFLD/NASH and the basics of AI. Subsequently, we introduce previous research on AI-based pathological diagnosis of NAFLD/NASH.

Hypofibrinolytic phenotype in Tsumura Suzuki Obese Diabetes (TSOD) mice unrelated to hyperglycemia.

Obesity and diabetes mellitus are associated with increased risk of arterial thrombosis and venous thromboembolism. Tsumura Suzuki Obese Diabetes (TSOD) mice are useful models for elucidating the molecular mechanisms of these diseases. We investigated normoglycemic [Ng]-TSOD mice with a metabolic abnormality that was accompanied by a coagulative and fibrinolytic state with a phenotype that distinctly differed from that of standard TSOD mice. As in TSOD mice, plasminogen activation inhibitor-1 (PAI-1) that inhibits fibrinolysis was substantially augmented in Ng-TSOD mice, suggesting that they are hypofibrinolytic. However, blood clotting parameters were within the normal range in Ng-TSOD mice. These findings indicated that Ng-TSOD mice are novel models with a hypofibrinolytic phenotype that is not associated with hyperglycemia.

Transport and Golgi organization 2 deficiency with a prominent elevation of C14:1 during a metabolic crisis: A case report.

Mutations in transport and Golgi organization 2 homolog (TANGO2) have recently been described as a cause of an autosomal recessive syndrome characterized by episodes of metabolic crisis associated with rhabdomyolysis, cardiac arrhythmias, and neurodegeneration. Herein, we report a case of a one-and-a-half-year-old Japanese girl, born to nonconsanguineous parents, who presented with metabolic crisis characterized by hypoglycemia with hypoketonemia, rhabdomyolysis, lactic acidosis, and prolonged corrected QT interval (QTc) at the age of 6 months. Acylcarnitine analysis during the episode of crisis showed prominent elevation of C14:1, suggesting very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency. In addition, worsening rhabdomyolysis was observed after intravenous administration of L-carnitine. VLCAD deficiency was initially suspected; however, the enzyme activity in lymphocytes was only mildly decreased at the gene carrier level, and no mutation in the VLCAD gene (ADADVL) was detected. Subsequently, acylcarnitine analysis was nonspecific at 17-h fasting and almost normal during the stable phase. Eventually, a trio whole-exome sequencing revealed a compound heterozygous variant of two novel variants in the TANGO2 gene, a missense variant, and a deletion of exon 7. This is the first case of TANGO2 deficiency in Asians. Our case suggests that elevated C14:1 may be seen in severe metabolic crises and that the use of L-carnitine should be avoided during metabolic crises.

[Pediatric nonalcoholic fatty liver disease/nonalcoholic steatohepatitis].

Nonalcoholic fatty liver disease (NAFLD)/nonalcoholic steatohepatitis (NASH) is a hepatic disease associated with metabolic syndrome. In recent years, pediatric NAFLD has increased in line with the increased prevalence of pediatric obesity. The estimated prevalence of pediatric NAFLD is 2.6-9.6%. With regard to the pathogenesis of NAFLD/ NASH, the "two-hit" or "multiple-hit" hypothesis is widely accepted, and many genetic and environmental factors are associated with the development of NAFLD/NASH. Liver biopsy is regarded as the gold standard for the diagnosis of NAFLD/NASH. Pediatric NAFLD has different histopathological characteristics from those of adult NAFLD. Although pharmacotherapy has been studied in clinical trials, lifestyle modification by diet and exercise remains the mainstay of treatment for NAFLD/NASH.

In vitro synthesis of mucin-type O-glycans using saccharide primers comprising GalNAc-Ser and GalNAc-Thr residues.

Mucin-type O-glycosylation of serine or threonine residue in proteins is known to be one of the major post-translational modifications. In this study, two novel alkyl glycosides, Nα-lauryl-O-(2-acetamido-2-deoxy-α-d-galactopyranosyl)-l-serineamide (GalNAc-Ser-C12) and Nα-lauryl-O-(2-acetamido-2-deoxy-α-d-galactopyranosyl)-l-threonineamide (GalNAc-Thr-C12) were synthesized as saccharide primers to prime mucin-type O-glycan biosynthesis in cells. Upon incubating human gastric cancer MKN45 cells with the saccharide primers, 22 glycosylated products were obtained, and their structures were analyzed using liquid chromatography-mass spectrometry and enzyme digestion. The amounts of glycosylated products were dependent on the amino acid residues in the saccharide primers. For example, in vitro synthesis of T antigen (Galß1-3GalNAc), fucosyl-T (Fucα1-2Galß1-3GalNAc), and sialyl-T (NeuAcα2-3Galß1-3GalNAc) preferred a serine residue, whereas sialyl-Tn (NeuAcα2-6GalNAc) preferred a threonine residue. Furthermore, the glycosylated products derived from GalNAc-Ser/Thr-C12 and Gal-GalNAc-Ser/Thr-C12 using cell-free synthesis showed the same amino acid selectivity as those in the cell experiments. These results indicate that glycosyltransferases involved in the biosynthesis of mucin-type O-glycans distinguish amino acid residues conjugated to GalNAc. The saccharide primers developed in this study might be useful for comparing mucin-type oligosaccharides in cells and constructing oligosaccharide libraries to study cell function.

Age-dependent sex difference of non-alcoholic fatty liver disease in TSOD and db/db mice.

According to previous clinical studies, the prevalence of non-alcoholic fatty liver disease (NAFLD) is higher in men than women only during the reproductive age. Animal models of NAFLD that reflect sex differences in humans have not been established. In this study, we examined sex differences in the hepatic lesions of Tsumura Suzuki obese diabetes (TSOD) and db/db mice, which are representative genetic models of NAFLD. Male and female TSOD and db/db mice were fed with a normal diet and tap water ad libitum. Six male and female mice of each strain were sacrificed at the ages of 3 and 9 months, respectively, and serum biochemical, pathological, and molecular analyses were performed. Serum aspartate aminotransferase (AST) levels were significantly higher in male than female mice of both strains at the age of 3 months; however, at 9 months, significant sex differences were not observed. Similarly, alanine aminotransferase (ALT) levels were significantly higher in male mice than in female TSOD mice at the age of 3 months; however, at 9 months, significant sex differences were not observed. Image analysis of histological slides revealed that the frequency of the steatotic area was significantly higher in male than female db/db mice at the age of 3 months; however, significant sex differences were not observed at 9 months. The frequency of Sirius red-positive fibrotic area was significantly higher in male than female mice in both strains at the age of 3 months; however, significant sex differences were not observed at 9 months. Serum AST and ALT levels and hepatic steatosis and fibrosis in TSOD and db/db mice showed age-dependent sex differences consistent with those observed in human NAFLD. These mice may be suitable for studying sex differences of the disease.

The Efficacy of Vitamin K, A Member Of Naphthoquinones in the Treatment of Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND: Redox dysregulation originating from metabolic alterations in cancer cells contributes to their proliferation, invasion, and resistance to therapy. Conversely, these features represent a specific vulnerability of malignant cells that can be selectively targeted by redox chemotherapeutics. Amongst them, Vitamin K (VitK) carries the potential against cancer stem cells, in addition to the rest of tumor mass. OBJECTIVES: To assess the possible benefits and safety of VitK for cancer treatment using a systematic review and meta-analysis with a mixed-methods approach. METHODS: We performed a systematic search on several electronic databases for studies comparing VitK treatment with and without combination to the control groups. For quantitative studies, fully or partially reported clinical outcomes such as recurrence rates, survival, overall response and adverse reactions were assessed. For qualitative studies, a narrative synthesis was accomplished. RESULTS: Our analysis suggested that the clinical outcome of efficacy, the pooled hazard ratio for progression-free survival, and the pooled relative risk for overall survival, and overall response were significantly higher in the VitK therapy group compared to the placebo group (p<0.05). We did not observe any significant difference in the occurrence of adverse events between groups. Among qualitative studies, VitK treatment targeting myelodysplastic syndrome and advanced solid tumors resulted in 24.1% and 10% of clinical response, respectively. CONCLUSION: VitK not only exerts antitumor effects against a wide range of tumor types, but it also has excellent synergism with other therapeutic agents.

No inhibitory effects of (-)-epigallocatechin gallate and lycopene on spontaneous hepatotumorigenesis in C3H/HeN mice.

Although several studies have indicated that (-)-epigallocatechin gallate (EGCG) and lycopene, representative dietary antioxidants, inhibit chemically induced animal tumorigenesis, only a few studies have examined the inhibitory effects of these compounds on spontaneous liver tumorigenesis in rodents. In this study, we investigated the inhibitory effects of these compounds on the formation of spontaneous liver tumors in C3H/HeN mice. We used xeroderma pigmentosum group A (XPA) gene-deficient mice to simultaneously examine whether the knockout mice could be used as a sensitive animal model. Inaddition, we examined the levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG)--a marker of reactive oxygen species-induced DNA injury--in liver tissue. Male XPA +/+, XPA +/-, and XPA -/- mice with a C3H/HeN genetic background were divided into 3 groups: control, EGCG, and lycopene. Autopsy at 18 months of age revealed that EGCG and lycopene did not exhibit obvious suppressive effects on the development of liver tumors in any XPA genotype; further, the XPA genotype did not influence any susceptibility to liver tumors. With regard to 8-OHdG levels in non-tumorous liver tissue at 8 months of age, EGCG showed no significant inhibitory effects and lycopene showed significant inhibitory effects only in XPA +/- mice. The present study demonstrates that contrary to previous reports of the inhibitory effects of EGCG and lycopene on the development of various carcinogen-induced animal tumors, these compounds exert no chemopreventive effects on spontaneous liver tumorigenesis in C3H/HeN mice. EGCG and lycopene may inhibit carcinogen-induced tumors through properties other than their antioxidant abilities.

Oral Recombinant Methioninase Prevents Nonalcoholic Fatty Liver Disease in Mice on a High Fat Diet.

BACKGROUND/AIM: We have recently shown that oral recombinant methionase (o-rMETase) prevents obesity and diabetes onset in mice on a high-fat (HF) diet. The present study aimed to determine if o-rMETase can inhibit the onset of nonalcoholic fatty liver disease (NAFLD) onset in mice on a high-fat diet. MATERIALS AND METHODS: Male C57BL/6J mice in the control group were fed a normal-fat diet (NFD) (+6.5% fat), and other mice were fed a high-fat (HF) diet (+34.3% fat). Then, the mice on the HF diet were divided into two dietary groups: i) HF+phosphate buffered saline (PBS) group, and ii) HF+o-rMETase group. RESULT: The fatty change score in the livers of mice treated with HF+PBS increased to an average of 2.6 during the experimental period of 8 weeks. In contrast, the fatty change in the livers of mice on the HF+o-rMETase group had an average score of 0.92 (p=0.04, HF+PBS vs HF+o-rMETase). CONCLUSION: o-rMETase inhibited the onset of NAFLD as well as prevented obesity and the onset of diabetes on a high-fat diet, offering a possibility of a new paradigm to prevent liver cirrhosis or liver cancer via NAFLD.