Deniz Nart

Differential expression of Caveolin-1 in hepatocellular carcinoma: correlation with differentiation state, motility and invasion

BackgroundCaveolin-1 is the main component of caveolae membrane structures and has different roles during tumorigenesis in different cancer types with varying expression profiles, indicating that the role of caveolin-1 varies according to tumor type. In this study, we investigated the role and expression of caveolin-1 in hepatocellular carcinogenesis.MethodsWe analyzed the expression of Caveolin-1 in 96 hepatocellular carcinoma (HCC), 29 cirrhosis, 20 normal liver tissues and 9 HCC cell lines by immunostaining and western blotting, respectively. After caveolin-1 was stably transfected to HepG2 and Huh7 cells, the effects of Caveolin-1 on the cellular motility, matrix invasion and anchorage-independent growth were studied. Also, caveolae structure was disrupted in endogenously caveolin expressing cells, SNU 449 and SNU 475 by addition of methyl-β-cyclodextrin and analyzed cellular motility and invasion.ResultsIn HCC cell lines, Caveolin-1 expression is correlated to differentiation and basal motility status of these cells. The percentage of Caveolin-1 positivity was found extremely low in normal liver tissue (5%) while it was increased in cirrhosis (45%) and in HCC (66%) (p = 0.002 and p = 0.001 respectively). Cav-1 expression in poorly differentiated HCC samples has been found significantly higher than well differentiated ones (p = 0.001). The caveolin-1 expression was found significantly higher in tumor cells than its peritumoral cirrhotic tissues in HCC samples (p < 0.001). Additionally, the patients with positive staining for Caveolin-1 had significantly higher portal vein invasion than those with negative staining (p = 0.02). Caveolin-1 overexpression increased motility and invasion of HepG2 and Huh7 cells. And disruption of caveolae results in a dramatic decline in both motility and invasion abilities in SNU-449 and SNU-475 cells. Furthermore, caveolin-1 overexpression resulted in down-regulation of E-cadherin while up-regulation of Vimentin. Also, it increased secreted MMP-2 and expression levels of MMP-9 and MT1-MMP. There was no significant difference in colony formation in soft agar between stable clones and parental ones.ConclusionIn conclusion, stepwise increase in Cav-1 expression in neoplastic stage with respect to pre-neoplastic stage during hepatocellular carcinogenesis and its ability to stimulate HCC cell motility and invasiveness indicate that this protein plays a crucial role in tumor progression.

Infliximab: a new therapeutic agent in acute pancreatitis?

Purpose Tumor necrosis factor alpha (TNF-alpha) has a central role in the pathogenesis of acute pancreatitis and related systemic complications. The aim of this study is to investigate the therapeutic effectiveness of monoclonal TNF antibody (infliximab) in acute edematous and severe necrotizing pancreatitis models in rats. Methods One hundred rats were randomly divided into 10 groups. Acute edematous pancreatitis (AEP) was induced by injection of cerulein 20 &mgr;g/kg 4 times subcutaneously at hourly intervals. Severe necrotizing pancreatitis (SNP) was induced by retrograde injection of 3% taurocholate into the common biliopancreatic duct. Infliximab 8 mg/kg was given via intravenous infusion. Serum amylase activity, pancreatic histopathology, myeloperoxidase enzyme activity (MPO), and pulmonary changes were assessed. Results Infliximab treatment significantly decreased serum amylase activity (11939 ± 1914 U/L versus 3458 ± 915 U/L, P < 0.001) and histopathologic score (4.1 ± 0.5 versus 1.5 ± 0.3, P < 0.001) in AEP. It also suppressed neutrophil infiltration and MPO activity of the pancreatic tissue. In SNP, infliximab treatment was found to decrease pathologic score (9.4 ± 1.2 versus 3.6 ± 0.8, P < 0.001) and serum amylase activity (20442 ± 2375 versus 8990 ± 1730, P < 0.01). It ameliorated both parenchymal and fatty tissue necrosis of the pancreas. Infliximab also alleviated alveolar edema and acute respiratory distress syndrome like pulmonary complications, but the difference was not significant. Conclusions Chimeric TNF antibody, infliximab, should be evaluated for treatment of acute pancreatitis.

Expression of matrix metalloproteinase‐9 in predicting prognosis of hepatocellular carcinoma after liver transplantation

Matrix metalloproteinases (MMPs) are known to play an important role in cell migration during cancer invasion by degrading extracellular matrix proteins. This study aimed to determine the role of MMP‐9 in hepatocellular carcinoma (HCC) carcinogenesis. Eighty‐nine cases who underwent liver transplantation for HCC in cirrhotic liver were selected for this study. The tumor characteristics such as nodule number, maximal diameter, portal vein invasion, and the preoperative alpha‐fetoprotein levels were reviewed. The intensity of immunostaining and the percentage of immunoreactive cells with MMP‐9 were evaluated. All patients were evaluated for HCC recurrence and/or death, and cause of death was noted. There was a lower survival and more recurrence risk among participants with 4 or more nodules exceeding 3 cm in diameter, with poorly differentiated tumor, and with large‐vessel involvement. Eleven patients developed recurrent HCC (12.4%). Twelve patients died as a result of HCC (13.5%). Among 89 HCCs, the incidences of a weak (+) and moderate (++) expression of MMP‐9 in carcinoma cells were 30.3% (23/89) and 43.8% (39/89), respectively. Increased expression and intensity of MMP‐9 were found to be inversely associated with poor tumor differentiation (P = 0.016, P = 0.009, respectively). A significant correlation between expression and intensity of MMP‐9 and large vascular invasion (P = 0.01, and P = 0.03) was also observed. As far as prognosis is concerned, increased immunoreactivity and intensity of MMP‐9 were found to exert an unfavorable impact on overall survival rates (P < 0.01, P = 0.01, respectively) and recurrences (P = 0.001, P = 0.02). Multivariate analyses revealed that MMP‐9 staining percentage (P = 0.007) and portal vein invasion (P = 0.002) were independent predictors of survival, whereas the only independent predictor of recurrences was portal vein invasion (P = 0.007). In this study, our results indicate a positive association between MMP‐9 expression and histopathologic parameters that indicate poor prognosis. We conclude that together, MMP‐9 staining percentage and portal vein invasion in HCC may aid to predict poor outcome. Nevertheless MMP‐9 staining percentage is expected to be a potential predictive marker on survival and needs to be studied more in detail. Liver Transpl 16:621‐630, 2010.

Hepatocellular carcinoma in children and effect of living-donor liver transplantation on outcome

Abstract:  Hepatocellular carcinoma (HCC) is primarily observed in the older children and in most cases it develops in association with liver cirrhosis. Liver transplantation offers a good chance for long‐term cure. To evaluate the outcome of children with HCC and the impact of living‐donor orthotopic liver transplantation (OLT) on survival a retrospective review of radiographic, laboratory, pathologic, and therapeutic data in 13 children (six female and seven male) with chronic liver disease accompanied with HCC were studied. The patients were divided into two groups according to therapeutic modality: transplanted and non‐transplanted patients. Kaplan–Meier survival curves in various therapeutic groups were plotted. The mean age of patients was 6.4 ± 4.8 yr. Pediatric end‐stage liver disease score was adapted to model for end‐stage liver disease score for HCC and ranged between 1–44 and 18–44, respectively. The underlying liver diseases were tyrosinemia type 1 (n = 6), chronic hepatitis B infection (n equals;6), glycogen storage disease type 1 (n = 1). Alfa‐feto protein levels were elevated in all patients except one. Median number of tumor nodules was three (1–10), median maximal diameter of tumor nodules was 3.4 cm (0.5–8). Eleven patients were eligible for OLT whereas two patients were not eligible. Seven of the 11 patients considered for transplantation underwent living‐donor OLT. Remaining four patients died while waiting on cadaveric transplant list. Overall 1 and 4‐yr survival rates for all patients were 53.3 and 26.6%, respectively, and were found significantly higher in transplanted children than non‐transplanted children (72%, 72% vs. 33% and 16.6%). No patient had tumor recurrence at median of 36‐month follow‐up after OLT. OLT is a life‐saving procedure for children with chronic liver disease accompanying with HCC. Living‐donor OLT avoids the risk of tumor progression and transplant ineligibility in these children.

Risk factors and consequences of post-transplant diabetes mellitus.

Demirci MS, Toz H, Yılmaz F, Ertilav M, Asci G, Ozkahya M, Zeytinoglu A, Nart D, Ok E. Risk factors and consequences of post‐transplant diabetes mellitus.
Clin Transplant 2010 DOI: 10.1111/j.1399‐0012.2010.01247.x.
© 2010 John Wiley & Sons A/S.

Breast carcinomas with choriocarcinomatous features: case reports and review of the literature.

Breast cancer with choriocarcinomatous features is rare. This report describes four cases of breast cancer with choriocarcinomatous features. The tumor cells were positive for human placental lactogen (hPL) and human chorionic gonadotropin (hCG) by immunohistochemistry. The cases reported in the literature had a poor prognosis and the patients died within a few months after the diagnosis. In this series, two cases were lost to follow‐up, but the other two have had disease‐free survival for 2 and 4 years, respectively.

Inhibition of renin-angiotensin system in experimental acute pancreatitis in rats: a new therapeutic target?

OBJECTIVE Pancreatic renin-angiotensin system has been implied to play a role in the regulation of pancreatic functions and could be a new therapeutic target in acute pancreatitis. The aim of this study was to evaluate the therapeutic potential of angiotensin-converting-enzyme inhibition by captopril and angiotensin II type 1 receptor inhibition by L-158809 and losartan experimentally in acute pancreatitis. DESIGN Rats were randomly divided into 15 groups. Acute edematous pancreatitis was induced by injection of cerulein 20microg/kg SC four times at hourly intervals. Severe necrotizing pancreatitis was induced by retrograde injection of 3% taurocholate into the biliary-pancreatic duct. INTERVENTIONS Captopril, L-158809 and losartan were given intraperitoneally. Main outcome features: pancreatic pathology, pancreatic myeloperoxidase activity and serum amylase activity were assessed. RESULTS Captopril decreased serum amylase (10,809+/-1867 vs. 4085+/-1028U/L, p<0.01), myeloperoxidase activity (3.5+/-0.5 vs. 1.5+/-0.1, p<0.05) and histopathological score (5.0+/-0.4 vs. 1.1+/-0.5, p<0.01) in acute edematous pancreatitis. In taurocholate induced severe necrotizing pancreatitis captopril ameliorated histopathological score (10.1+/-1.2 vs. 3.4+/-0.5, p<0.01), pancreatic parenchymal necrosis (4.5+/-0.6 vs. 0.0+/-0.0, p<0.001), fatty necrosis (2.8+/-0.9 vs. 0.1+/-0.1, p<0.01) and edema (2.1+/-0.3 vs. 1.4+/-0.3, p<0.05). However, L-158809 did not have similar beneficial effects on acute pancreatitis in rats while losartan decreased pancreatic parenchymal necrosis and neutrophil infiltration. CONCLUSIONS This study not only demonstrated the differential effects of captopril, losartan and L-158809 in acute pancreatitis but also showed that there is still much to investigate about pancreatic renin-angiotensin system. Inhibition of angiotensin-converting enzyme should be evaluated carefully as a potential new therapeutic target in acute pancreatitis.

Association between hepatitis B and hepatocellular carcinoma recurrence in patients undergoing liver transplantation.

BACKGROUND/AIMS Hepatitis B virus (HBV) and hepatocellular carcinoma (HCC) recurrences affect both patient and graft survivals post-orthotopic liver transplantation (OLT) in HBV patients with HCC. We analyzed the relationship between HBV and HCC recurrence in a large cohort of HBV-OLT patients with versus without HCC. METHODS Two hundred eighty-seven HBV patients with OLT (72 also with HCC) were included in the study. Mean follow-up in the post-OLT period was 31.7 +/- 24.7 (range, 3-119) months. RESULTS Post-OLT HBV recurrence observed in 10.1% of patients was more prevalent among the HCC group; 23.6% versus 5.5% in patients with and without HCC, respectively. The mean interval for the development of HBV recurrence was 39.5 +/- 28.5 (range, 2-99) months. Among 72 HCC patients, 8 patients (11.1%) had recurrent HCC, and 7 of them also had HBV recurrence. The mean interval for the development of HCC recurrence was 11.2 +/- 7.85 (range, 2-23) months after OLT. OLT patients with HCC with tumors exceeding the Milan criteria had worse 1-, 3-, and 5-year survival rates than patients with HCC meeting the Milan criteria. HBV and HCC recurrence-free survivals were significantly lower in patients with HCC and HBV recurrence, respectively. In the 7 patients with both HCC and HBV recurrence, mean HBV recurrence time was 9.42 +/- 6.75 months and mean HCC recurrence time was 9.57 +/- 6.75 months. There was a strong correlation between HBV and HCC recurrence times. Cox proportional hazards regression analysis showed that only HCC recurrence was a significant independent predictor of HBV recurrence (P < .001; hazard ratio [HR] = 26.94; 95% confidence interval [CI] = 10.81-67.11). On the other hand, HBV recurrence (P = .013; HR = 5.80; 95% CI = 1.45-23.17) and nodule count (P = .014; HR = 13.08; 95% CI = 1.70-100.83) were significant predictors of HCC recurrence. CONCLUSIONS HBV and HCC recurrences demonstrate a close relationship in patients with OLT.

Reciprocal Activating Crosstalk between c-Met and Caveolin 1 Promotes Invasive Phenotype in Hepatocellular Carcinoma

c-Met, the receptor for Hepatocyte Growth Factor (HGF), overexpressed and deregulated in Hepatocellular Carcinoma (HCC). Caveolin 1 (CAV1), a plasma membrane protein that modulates signal transduction molecules, is also overexpressed in HCC. The aim of this study was to investigate biological and clinical significance of co-expression and activation of c-Met and CAV1 in HCC. We showed that c-Met and CAV1 were co-localized in HCC cells and HGF treatment increased this association. HGF-triggered c-Met activation caused a concurrent rise in both phosphorylation and expression of CAV1. Ectopic expression of CAV1 accelerated c-Met signaling, resulted in enhanced migration, invasion, and branching-morphogenesis. Silencing of CAV1 downregulated c-Met signaling, and decreased migratory/invasive capability of cells and attenuated branching morphogenesis. In addition, activation and co-localization of c-Met and CAV1 were elevated during hepatocarcinogenesis. In conclusion reciprocal activating crosstalk between c-Met and CAV1 promoted oncogenic signaling of c-Met contributed to the initiation and progression of HCC.

Macrophage migration inhibitory factor expression and MIF gene -173 G/C polymorphism in nonalcoholic fatty liver disease.

Aim To investigate the macrophage migration inhibitory factor (MIF) expression and −173 G/C polymorphism of the MIF gene in nonalcoholic fatty liver disease (NAFLD). Method Ninety-one patients with diagnosis of NAFLD and 104 healthy controls were included in the study. MIF −173 G/C polymorphism was detected using the PCR–restriction fragment length polymorphism based method. NAFLD was stratified as nonalcoholic steatohepatitis (NASH), probable NASH and steatosis, respectively in groups 1, 2 and 3, according to NAFLD Activity Score. MIF expression was detected by immunohistochemistry staining. Results Mean age of the patients was 50.1±9.6 years, and 54 of them were male. Serum alanine aminotransferase and aspartate aminotransferase were 50/83, 42/63 and 31/32, respectively in groups 1, 2 and 3, (P<0.05). Both the MIF expression of hepatocytes and mononuclear cells were more prominent in groups 1 and 2 than group 3. There was no correlation between MIF expression of hepatocytes and fibrosis stage. However, MIF expression of mononuclear cells significantly increased according to fibrosis stage (P<0.05, R : 0.2). There was no significant correlation between MIF genotype and MIF expression in the liver. Conclusion MIF expression is significantly increased especially by mononuclear cells in liver tissue of patients with NASH secondary to inflammation. Thus, it should be considered as a consequence not a causal factor.