Focus on histological abnormalities of intrahepatic vasculature in chronic viral hepatitis.

BACKGROUND & AIMS: The histological intrahepatic microvasculature lesions have not been deeply investigated outside the setting of portal hypertension. The aim of this study was to analyse the type and the prevalence of microvasculature abnormalities and their correlation with inflammatory activity, fibrosis stage and tissue markers of fibrogenesis, angiogenesis and oxidative DNA damage in liver biopsies obtained from patients with chronic viral hepatitis. METHODS: Seventy-four liver biopsies from untreated patients affected by hepatitis B (22 cases) and C (52 cases) were included. The presence of microvascular changes was correlated with (i) the severity of the activity and fibrosis; (ii) immunohistochemical markers of angiogenesis (CD34) and hepatic stellate cells activation (alpha-smooth muscle actin); (iii) a tissue marker of oxidative damage (8-OHdG adducts). RESULTS: Sixty-five out of 74 biopsies (87.8%) showed vascular lesions. Portal angiomatosis was the most prevalent (62.2%) and it was associated with, on 1 side, the fibrosis stage at both univariate (P < .0001) and multivariate analysis (P = .01, OR = 9.4 [1.6-54]) and, on the other, with angiogenesis (P = .05) and hepatic stellate cells activation (P = .002). Interestingly, 36/46 cases with portal angiomatosis were at early/intermediate fibrosis stage. The hepatic stellate cells activation was also associated with the presence of aberrant periportal vessels (P = .01). CONCLUSIONS: The histological alterations of intrahepatic microvasculature, usually seen in cirrhosis and portal hypertension, occur in chronic viral hepatitis even at early/intermediate fibrosis stages. Their correlation with angiogenesis and fibrogenesis supports a possible involvement in disease progression.

Squamous Cellular Carcinoma Antigen Serum Determination as a Biomarker of Barrett Esophagus and Esophageal Cancer: A Phase III Study.

GOAL: To evaluate the potential role of the determination of the immunocomplexed form of squamous cell carcinoma antigen [SCCA-immunoglobulin (Ig)M] for the screening of Barrett esophagus (BE) and esophageal adenocarcinoma (EAC). BACKGROUND: The cost-effectiveness of surveillance in BE is still debated and the use of biomarkers in screening and surveillance still not recommended. No information is available regarding SCCA-IgM determination in BE. STUDY: SCCA-IgM levels were determined (enzyme-linked immunosorbent assay) in 231 patients prospectively recruited, 71 with BE, 53 with EAC, and 107 controls, including 42 blood donors and 65 patients with gastroesophageal reflux. SCCA-IgM cutoffs between BE/EAC and controls and for BE "at risk" versus short nondysplastic BE were calculated by receiver operating characteristic curves. Immunostaining for SCCA-IgM was obtained in a subgroup of patients. RESULTS: Median SCCA-IgM values were significantly higher in BE and EAC than in controls (P=0.0001). Patients with SCCA-IgM levels above the cutoff had a 33 times higher relative risk of harboring BE or EAC (P=0.0001). Patients "at risk," with long or dysplastic BE had SCCA-IgM levels significantly higher than those with short nondysplastic BE (P=0.035) and patients with SCCA-IgM above the cutoff had a 8 times higher relative risk of having BE "at risk." SCCA was expressed in Barrett mucosa but not in cardiac metaplasia. CONCLUSIONS: Serum SCCA-IgM determination allows the identification of patients at risk for BE/EAC and the stratification of BE patients in subgroups with different cancer risk. Because of the still limited number of controls, large, prospective studies are required to confirm this evidence.

Differential timing of oxidative DNA damage and telomere shortening in hepatitis C and B virus-related liver carcinogenesis.

In viral hepatitis, inflammation is correlated with chronic oxidative stress, one of the biological events leading to DNA damage and hepatocellular carcinoma (HCC) development. Aim of this study was to investigate the complex molecular network linking oxidative damage to telomere length and telomerase activity and regulation in hepatitis C and B virus-related liver carcinogenesis. We investigated 142 patients: 21 with HCC (in both tumor and peritumor tissues) and 121 with chronic viral hepatitis in different stages. We evaluated 8-hydroxydeoxyguanosine (8-OHdG), marker of oxidative DNA damage, OGG1 gene polymorphism, telomere length, telomerase activity, TERT promoter methylation, and mitochondrial TERT localization. In hepatitis C-related damage, 8-OHdG levels increased since the early disease stages, whereas hepatitis B-related liver disease was characterized by a later and sharper 8-OHdG accumulation (P = 0.005). In C virus-infected patients, telomeres were shorter (P = 0.03), whereas telomerase activity was higher in tumors than that in the less advanced stages of disease in both groups (P = 0.0001, P = 0.05), with an earlier increase in hepatitis C. Similarly, TERT promoter methylation was higher in tumor and peritumor tissues in both groups (P = 0.02, P = 0.0001). Finally, TERT was localized in mitochondria in tumor and peritumor samples, with 8-OHdG levels significantly lower in mitochondrial than those in genomic DNA (P = 0.0003). These data describe a pathway in which oxidative DNA damage accumulates in correspondence with telomere shortening, telomerase activation, and TERT promoter methylation with a different time course in hepatitis B and C virus-related liver carcinogenesis. Finally, TERT localizes in mitochondria in HCC, where it lacks a canonical function.

Oxidative damage in the progression of chronic liver disease to hepatocellular carcinoma: an intricate pathway.

The histo-pathologic and molecular mechanisms leading to initiation and progression of hepatocellular carcinoma (HCC) are still ill-defined; however, there is increasing evidence that the gradual accumulation of mutations, genetic and epigenetic changes which occur in preneoplastic hepatocytes results in the development of dysplastic foci, nodules, and finally, overt HCC. As well as many other neoplasias, liver cancer is considered an "inflammatory cancer", arising from a context of inflammation, and characterized by inflammation-related mechanisms that favor tumor cell survival, proliferation, and invasion. Molecular mechanisms that link inflammation and neoplasia have been widely investigated, and it has been well established that inflammatory cells recruited at these sites with ongoing inflammatory activity release chemokines that enhance the production of reactive oxygen species. The latter, in turn, probably have a major pathogenic role in the continuum starting from hepatitis followed by chronic inflammation, and ultimately leading to cancer. The relationship amongst chronic liver injury, free radical production, and development of HCC is explored in the present review, particularly in the light of the complex network that involves oxidative DNA damage, cytokine synthesis, telomere dysfunction, and microRNA regulation.

Diagnostic and prognostic role of SCCA-IgM serum levels in hepatocellular carcinoma (HCC).

BACKGROUND AND AIM: The serpin squamous cell carcinoma antigen complexed with IgM (SCCA-IgM) has been reported as a promising serological marker for hepatocellular carcinoma (HCC). We aimed to further evaluate SCCA-IgM diagnostic accuracy and to determine its prognostic role. METHODS: SCCA-IgM levels were determined in 327 sera obtained from 81 HCC patients, 206 cirrhotics and 40 healthy blood donors (controls). Sensitivity, specificity, correlation with clinical and tumor parameters and with survival were evaluated. RESULTS: HCC patients had SCCA-IgM levels significantly higher than controls and cirrhotics (P < 0.0001). Sensitivity, specificity, positive and negative predictive values for HCC were 89%, 50%, 41% and 92%, respectively. In comparison, sensitivity and specificity for alphafetoprotein were 48% and 85%. SCCA-IgM levels were not significantly correlated with clinical or biological variables. With a cut-off of 130 AU/mL (receiver operating characteristic curves), SCCA-IgM proved efficient in the prediction of prognosis, identifying the patients with long overall survival (efficiency validated in the homogenous subgroup of patients with intermediate-stage HCC undergoing transarterial chemoembolization) and predicting progression-free survival. A Cox multivariate analysis confirmed SCCA-IgM predictive value, identifying tumor size and SCCA-IgM levels as independent predictors of survival. A reduction in SCCA-IgM levels correlated with response to treatment. CONCLUSIONS: SCCA-IgM is a sensitive marker of HCC in patients with cirrhosis even though lacking in specificity. The determination of the levels of the marker in HCC patients is highly efficient in predicting the patients' prognosis, identifying those with long overall and progression-free survival and the responders and should be introduced in the clinical practice.

Oxidative DNA damage in Barrett mucosa: correlation with telomeric dysfunction and p53 mutation.

BACKGROUND: Barrett esophagus develops in a scenario of chronic inflammation, linked to free radical formation and oxidative DNA damage. Eight-hydroxydeoxyguanosine, the main oxidative DNA adduct, is partially repaired by a glycosylase (OGG1) whose polymorphism is associated to a reduced repair capacity. Telomeres are particularly prone to oxidative damage, which leads to shortening and cell senescence, while elongation, by telomerase activity, is linked to cell immortalization and cancer. Limited data are available on this point with respect to Barrett esophagus. This study aimed to evaluate the link among 8-hydroxydeoxyguanosine, OGG1 polymorphism, telomerase activity, telomere length, and p53 mutation in Barrett progression. METHODS: Forty consecutive patients with short- and long-segment Barrett esophagus and 20 controls with gastroesophageal reflux disease without Barrett esophagus were recruited. Analysis of biopsy samples was undertaken to study 8-hydroxydeoxyguanosine levels, OGG1 polymorphism, telomerase activity, and telomere length. Serum samples were obtained for p53 mutation. RESULTS: Controls had significantly lower levels of 8-hydroxydeoxyguanosine and telomerase activity, with normal telomere length and no p53 mutation. In short-segment Barrett esophagus, 8-hydroxydeoxyguanosine levels were higher and telomeres underwent significant shortening, with stimulation of telomerase activity but no p53 mutations. In long-segment Barrett esophagus, 8-hydroxydeoxyguanosine reached maximal levels, with telomere elongation, and 42 % of the patients showed p53 mutation. CONCLUSIONS: In Barrett patients, with disease progression, oxidative DNA damage accumulates, causing telomere instability, telomerase activation, and, in a late phase, mutations in the p53 gene, thus abrogating its activity as the checkpoint of proliferation and apoptosis, and facilitating progression to cancer.

Effects of coffee consumption in chronic hepatitis C: a randomized controlled trial.

BACKGROUND: Coffee is associated with a reduced risk of hepatocellular carcinoma in patients with chronic C hepatitis. This prospective trial was aimed at assessing the mechanisms underlying coffee-related protective effects. METHODS: Forty patients with chronic hepatitis C were randomized into two groups: the first consumed 4 cups of coffee/day for 30 days, while the second remained coffee "abstinent". At day 30, the groups were switched over for a second month. RESULTS: At baseline, aspartate aminotransferase and alanine aminotransferase were lower in patients drinking 3-5 (Group B) than 0-2 cups/day (Group A) (56 ± 6 vs 74 ± 11/60 ± 3 vs 73 ± 7 U/L p=0.05/p=0.04, respectively). HCV-RNA levels were significantly higher in Group B [(6.2 ± 1.5) × 10(5)vs (3.9 ± 1.0) × 10(5)UI/mL, p=0.05]. During coffee intake, 8-hydroxydeoxyguanosine and collagen levels were significantly lower than during abstinence (15 ± 3 vs 44 ± 16 8-hydroxydeoxyguanosine/10(5)deoxyguanosine, p=0.05 and 56 ± 9 vs 86 ± 21 ng/mL, p=0.04). Telomere length was significantly higher in patients during coffee intake (0.68 ± 0.06 vs 0.48 ± 0.04 Arbitrary Units, p=0.006). Telomere length and 8-hydroxydeoxyguanosine were inversely correlated. CONCLUSION: In chronic hepatitis C coffee consumption induces a reduction in oxidative damage, correlated with increased telomere length and apoptosis, with lower collagen synthesis, factors that probably mediate the protection exerted by coffee with respect to disease progression.

Circulating free DNA in the progression of liver damage to hepatocellular carcinoma.

PURPOSE: Circulating free DNA (cfDNA) is an extracellular DNA released in the blood by tumor apoptotic/necrotic cells. cfDNA determination has been proposed as a non-invasive and sensitive marker in the diagnosis of cancer. Our aim was to validate the quantification of cfDNA as a diagnostic and prognostic tool in hepatocellular carcinoma (HCC). METHODS: cfDNA was quantified by real-time PCR amplification of the hTERT gene in 142 plasma samples obtained from 66 patients with HCC, 35 with cirrhosis (CIRR) and 41 with advanced HCV-related chronic hepatitis (CH). RESULTS: cfDNA was documented in the plasma of 22 % of the CH patients, 57 % of those with CIRR and 61 % of HCC patients. Its concentration was lower in CH with respect to CIRR and HCC (p = 0.02). A cutoff value in the diagnosis of HCC was calculated by the ROC method (area under the curve 0.69, 91 % sensitivity, 43 % specificity) considering HCC versus CH/CIRR, taken together. Patients with multinodular HCC showed significantly higher levels of cfDNA (p = 0.05). A cutoff value for cfDNA was also calculated for discriminating patients with long or short survival. Survival was significantly longer in patients with cfDNA below than in those above the cutoff value (37 vs. 24 months, p = 0.03). Similar results were obtained in the subgroups of patients with viral or with HCV-only etiology, with slightly higher overall diagnostic accuracy. CONCLUSIONS: The role of the quantitative analysis of cfDNA as a diagnostic test is debatable, but cfDNA levels discriminate patients with more advanced stages of disease, demonstrating a prognostic relevance in patients with HCC.

Oxidative DNA damage correlates with cell immortalization and mir-92 expression in hepatocellular carcinoma.

BACKGROUND: MicroRNAs expression has been extensively studied in hepatocellular carcinoma but little is known regarding the relationship, if any, with inflammation, production of reactive oxygen species (ROS), host's repair mechanisms and cell immortalization. This study aimed at assessing the extent of oxidative DNA damage (8-hydroxydeoxyguanosine - 8-OHdG) in different phases of the carcinogenetic process, in relation to DNA repair gene polymorphism, telomeric dysfunction and to the expression of several microRNAs, non-coding genes involved in post-transcriptional regulation, cell proliferation, differentiation and death. METHODS: Tissue samples obtained either at surgery, [neoplastic (HCC) and adjacent non-cancerous cirrhotic tissues (NCCT)] at percutaneous or laparoscopic biopsy (patients with HCV or HBV-related hepatitis or patients undergoing cholecystectomy) were analysed for 8-OHdG (HPLC-ED), OGG1 (a DNA repair gene) polymorphism (PCR-RFLP), telomerase activity, telomere length (T/S, by RT-PCR), Taqman microRNA assay and Bad/Bax mRNA (RT-PCR). Fifty-eight samples from 29 HCC patients (obtained in both neoplastic and peritumoral tissues), 22 from chronic hepatitis (CH) and 10 controls (cholecystectomy patients - CON) were examined. RESULTS: Eight-OHdG levels were significantly higher in HCC and NCCT than in CH and CON (p=0.001). Telomerase activity was significantly higher in HCC than in the remaining subgroups (p=0.002); conversely T/S was significantly lower in HCC (p=0.05). MiR-199a-b, -195, -122, -92a and -145 were down-regulated in the majority of HCCs while miR-222 was up-regulated. A positive correlation was observed among 8-OHdG levels, disease stage, telomerase activity, OGG1 polymorphisms and ALT/GGT levels. In HCC, miR-92 expression correlated positively with telomerase activity, 8-OHdG levels and Bad/Bax mRNA. CONCLUSIONS: The above findings confirm the accumulation, in the progression of chronic liver damage to HCC, of a ROS-mediated oxidative DNA damage, and suggest that this correlates with induction of telomerase activity and, as a novel finding, with over-expression of miR-92, a microRNA that plays a role in both the apoptotic process and in cellular proliferation pathways.

MINT31 methylation in gastric noninvasive neoplasia: potential role in the secondary prevention of gastric cancer.

Gastric cancer (GC) is still a leading cause of cancer-related death worldwide, and environmental, genetic, and epigenetic DNA changes are involved in the process of gastric carcinogenesis. The objective of this study was to establish the extent of DNA methylation at various CpG islands in GC and in precancerous changes [gastric noninvasive neoplasia (NIN)]. Eighty-one gastric samples were analyzed using methylation-specific PCR at several CpG islands. Thirty-eight samples were obtained at surgery [19 neoplastic (GC) and 19 nonneoplastic cancer-surrounding tissues (sGC)] and 43 at endoscopy (biopsies in 23 NIN patients and 20 controls). Hypermethylation of TPEF (a growth inhibitor), PTGER3 (a prostaglandin receptor isoform), and MINT31 (a promoter locus regulating calcium channels that is involved in p53 mutation) discriminated NIN and GC from normal mucosa, suggesting an early role as initiating events, whereas hypermethylation at ARGHAP20 developed with the progression from NIN to GC. MINT31 hypermethylation predicted persistence or worsening of NIN and cancer development. In conclusion, these data support a progressive accumulation of aberrant methylations in NIN and GC at various CpG islands with distinct time courses. With hypermethylation, the genes involved in regulating the balance between apoptosis and cell proliferation may become silenced and trigger gastric tumorigenesis. Hypermethylation of MINT31 predicted NIN persistence, as well as progression to higher grade or to GC, and might be used as a marker of GC risk.

Oxidative stress and inducible nitric oxide synthase induction in carcinogenesis.

BACKGROUND: Chronic inflammation is linked to an increased risk of cancer. The molecular mechanisms underlying this correlation have been long investigated and it is well known that the inflammatory cells recruited in the inflamed tissues release chemical mediators, in particular reactive oxygen species (ROS). With respect to digestive systems, ROS have been implicated in a number of pathologies, including Helicobacter pylori-related gastritis, Barrett's esophagus, inflammatory disease of the lower gastrointestinal tract, alcoholic liver disease and several other types of toxic and virus-mediated liver injury. ROS levels within cells and tissues are controlled by numerous antioxidant defense mechanisms, but in inflammation, ROS overproduction exceeds defenses and damage intracellular macromolecules, including nucleic acids, with formation of potentially mutagenic and carcinogenic DNA adducts. AIMS: This paper summarizes our own experience investigating the link between inflammation, ROS production and oxidative DNA damage as well as the impact of the above events on cytokine and growth factor release, oncogene activation, telomere instability and microRNA in H. pylori-related gastritis, Barrett's esophagus and, in particular, hepatitis C virus-related liver disease. The paper also describes, at least in part, the complex scenario involving nitric oxide production and its impact in some gastrointestinal diseases, as well as a number of other molecular and biochemical changes related to ROS production and inflammation. CONCLUSIONS: The paper falls obviously short of being an exhaustive summary of our understanding, but the data reported are intended as a stimulus to broaden the knowledge on the topic, also in view of the possible therapeutic implications of any advance obtained.