Marcus Bahra

Long-term outcome of liver transplants for chronic hepatitis C: a 10-year follow-up.

Background. Recurrence of hepatitis C (HCV) infection after orthotopic liver transplantation (OLT) in HCV-positive patients is almost universal. Severity of graft hepatitis increases during the long-term follow-up, and up to 30% of patients develop severe graft hepatitis and cirrhosis. However, there are still no clear predictors for severe recurrence. The aim of this study was to examine the 10-year outcome and risk factors for graft failure caused by HCV recurrence. Methods. In a prospective analysis, 234 OLTs in 209 HCV-positive patients with a median age of 53 years were analyzed. Immunosuppression was based on cyclosporine A or tacrolimus in different protocols. Predictors for outcome were genotype, viremia, donor variables, recipient demographics, postoperative immunosuppression, and human leukocyte antigen (HLA) compatibilities. Results. Actuarial 5-, and 10-year patient survival was 75.8% and 68.8%. Eighteen of 209 (8.7%) patients died because of HCV recurrence, which was responsible for 35.9% of the total 53 deaths. Significant risk factors for HCV-related graft failure in an univariate analysis were multiple steroid pulses, use of OKT3, and donor age greater than 40. However, in a multivariate analysis, multiple rejection treatments with steroids and OKT3 treatment proved to be significantly associated with HCV-related graft loss. Conclusions. The analysis of causes leading to graft failure in patients with HCV showed that HCV recurrence is responsible for one of three deaths in HCV-positive patients. Rejection treatment contributed significantly to an enhanced risk for HCV-related graft loss. New antiviral treatments, as well as adapted immunosuppressive protocols, will be necessary to further improve the outcome of HCV-positive patients after liver transplantation.

Google Goes Cancer: Improving Outcome Prediction for Cancer Patients by Network-Based Ranking of Marker Genes

Predicting the clinical outcome of cancer patients based on the expression of marker genes in their tumors has received increasing interest in the past decade. Accurate predictors of outcome and response to therapy could be used to personalize and thereby improve therapy. However, state of the art methods used so far often found marker genes with limited prediction accuracy, limited reproducibility, and unclear biological relevance. To address this problem, we developed a novel computational approach to identify genes prognostic for outcome that couples gene expression measurements from primary tumor samples with a network of known relationships between the genes. Our approach ranks genes according to their prognostic relevance using both expression and network information in a manner similar to Googles PageRank. We applied this method to gene expression profiles which we obtained from 30 patients with pancreatic cancer, and identified seven candidate marker genes prognostic for outcome. Compared to genes found with state of the art methods, such as Pearson correlation of gene expression with survival time, we improve the prediction accuracy by up to 7%. Accuracies were assessed using support vector machine classifiers and Monte Carlo cross-validation. We then validated the prognostic value of our seven candidate markers using immunohistochemistry on an independent set of 412 pancreatic cancer samples. Notably, signatures derived from our candidate markers were independently predictive of outcome and superior to established clinical prognostic factors such as grade, tumor size, and nodal status. As the amount of genomic data of individual tumors grows rapidly, our algorithm meets the need for powerful computational approaches that are key to exploit these data for personalized cancer therapies in clinical practice.

Treatment of Patients with Recurrent Hepatitis C after Liver Transplantation with Peginterferon Alfa-2b Plus Ribavirin

Background. Recurrent hepatitis C virus (HCV) after liver transplantation (OLT) is a major cause of graft loss in HCV-positive patients. In this study, we evaluated the efficacy and safety of pegylated interferon alfa-2b (peginterferon) and ribavirin treatment for recurrent HCV after OLT and analyzed the influence of antiviral treatment on the histological course of recurrent hepatitis. Methods. Twenty-five patients with recurrent HCV (genotype 1 n=20 and 2–4 n=5) received peginterferon (1 mg/kg/weekly) and ribavirin (600 mg) for 48 weeks. Viral load prior to treatment was below 1,000,000 (IU/ml) in 11 of 25 patients. Sustained antiviral response was defined as undetectable HCV-RNA in serum 6 months after stopping of therapy. All patients underwent liver biopsy prior to treatment and after 72 weeks. Results. Seventeen of 25 patients became HCV-RNA-negative after treatment (68%). Sustained virologic response (SVR) was achieved in 9/25 (36%) patients. Liver specimen showed increase of fibrosis from 1.7 to 2.0 within 72 weeks. Side effects like neutropenia (60%) and anemia (36%) were treated with G-CSF, erythropoietin, and dose reduction of peginterferon and ribavirin. Conclusions. The use of peginterferon is safe and effective in patients with recurrent HCV. Treatment of side effects, especially neutropenia or anemia, helped to maintain antiviral therapy. Despite a viral response of 68% during treatment, the patients showed further progress of recurrent hepatitis in liver specimen.

Golgi phosphoprotein 2 (GOLPH2) expression in liver tumors and its value as a serum marker in hepatocellular carcinomas.

Hepatocellular carcinomas (HCCs) and bile duct carcinomas (BDCs) have a poor prognosis. Therefore, surveillance strategies including sensitive and specific serum markers for early detection are needed. Recently, Golgi Phosphoprotein 2 (GOLPH2) has been proposed as a serum marker for HCC, but GOLPH2 expression data in liver tissues was not available. Using tissue microarrays and immunohistochemistry, we semiquantitatively analyzed GOLPH2 protein expression in patients with HCC (n = 170), benign liver tumors (n = 22), BDC (n = 114) and normal liver tissue (n = 105). A newly designed sandwich enzyme‐linked immunoassay (ELISA) was used to analyze GOLPH2 levels in the sera of patients with HCC (n = 62), hepatitis C virus (HCV) (n = 29), BDC (n = 10), and healthy control persons (n = 12). By immunohistochemistry 121/170 (71%) of HCC showed strong GOLPH2 expression, which was significantly associated with a higher tumor grade (P = 0.01). A total of 97/114 (85%) BDCs showed a strong GOLPH2 expression which proved to be an independent prognostic factor for overall survival (P < 0.05). Serum levels of GOLPH2 measured by ELISA were significantly elevated in patients with HCC with underlying HCV infection (median 18 mg/L, P < 0.05) and patients with BDC (median = 14.5 mg/L, P < 0.01) in comparison to healthy controls (median 4 mg/L). Conclusion: GOLPH2 protein is highly expressed in tissues of HCC and BDC. GOLPH2 protein levels are detectable and quantifiable in sera by ELISA. In patients with hepatitis C, serial ELISA measurements in the course of the disease appear to be a promising complementary serum marker in the surveillance of HCC. GOLPH2 should be further evaluated as a serum tumor marker in BDC on a larger scale. (HEPATOLOGY 2009.)

Relationship between the interleukin‐28b gene polymorphism and the histological severity of hepatitis C virus–induced graft inflammation and the response to antiviral therapy after liver transplantation

Up to 30% of liver transplants will develop graft cirrhosis within 5 years after liver transplantation (LT) due to recurrent HCV‐infection forwarding accelerated graft damage. Genetic variants of cytokines involved in the immune response may contribute to the degree of graft inflammation, fibrosis progression, and antiviral therapy outcome. The aim of our study was to analyze biochemical and histological inflammation extent based on protocol liver biopsies and to evaluate the role of genetic variants of IL‐28b in HCV‐related graft disease and antiviral treatment response. 183 patients, who underwent liver transplantation for HCV‐induced liver disease, were genotyped for IL‐28b (rs8099917, G ≥ T) by TaqMan Genotyping Assay. 56 of 159 patients have been successfully treated with interferon‐based antiviral therapy. 605 protocol liver biopsies performed 0.5 to 10 and more than 10 years after transplantation were evaluated according to Desmet and Scheuer classification of inflammation and fibrosis. Prevalence of IL‐28b‐genotypes was correlated with histological severity of graft damage, levels of aminotransferases, occurrence of acute cellular rejection, pre‐treatment viremia, and antiviral therapy outcome. Significant association of IL‐28b‐genotype distribution was observed to the median grade of inflammation (p < 0.001), mean levels of aminotransferases (ALT: p = 0.001, AST: p = 0.003), median pre‐treatment viremia level within 1 year after LT (p = 0.046) and interferon‐based antiviral therapy failure (p < 0.001). Among successfully treated patients, G‐allele was significantly less frequent, and the genotype GG was not present at all. No differences were observed regarding acute cellular rejection (p = 0.798) and fibrosis stages (p = 0.586). IL‐28b polymorphism seems to influence the degree of graft inflammation at biochemical and histological levels. G‐allele might serve as a marker for graft inflammation and as a predictor for unfavorable antiviral therapy outcome in HCV‐re‐infected LT‐population. Liver Transpl, 2011.

CYP3A5 mediates basal and acquired therapy resistance in different subtypes of pancreatic ductal adenocarcinoma

Although subtypes of pancreatic ductal adenocarcinoma (PDAC) have been described, this malignancy is clinically still treated as a single disease. Here we present patient-derived models representing the full spectrum of previously identified quasi-mesenchymal (QM-PDA), classical and exocrine-like PDAC subtypes, and identify two markers—HNF1A and KRT81—that enable stratification of tumors into different subtypes by using immunohistochemistry. Individuals with tumors of these subtypes showed substantial differences in overall survival, and their tumors differed in drug sensitivity, with the exocrine-like subtype being resistant to tyrosine kinase inhibitors and paclitaxel. Cytochrome P450 3A5 (CYP3A5) metabolizes these compounds in tumors of the exocrine-like subtype, and pharmacological or short hairpin RNA (shRNA)-mediated CYP3A5 inhibition sensitizes tumor cells to these drugs. Whereas hepatocyte nuclear factor 4, alpha (HNF4A) controls basal expression of CYP3A5, drug-induced CYP3A5 upregulation is mediated by the nuclear receptor NR1I2. CYP3A5 also contributes to acquired drug resistance in QM-PDA and classical PDAC, and it is highly expressed in several additional malignancies. These findings designate CYP3A5 as a predictor of therapy response and as a tumor cell–autonomous detoxification mechanism that must be overcome to prevent drug resistance.

High class I HDAC activity and expression are associated with RelA/p65 activation in pancreatic cancer in vitro and in vivo

BackgroundThe strong association between aberrant HDAC activity and the occurrence of cancer has led to the development of a variety of HDAC inhibitors (HDIs), which emerge as promising new targeted anticancer therapeutics.MethodsDue to the pivotal role of RelA/p65 in the tumorigenesis of pancreatic neoplasia we examined the expression of class I HDACs 1, 2 and 3 in a large cohort of human pancreatic carcinomas and correlated our findings with RelA/p65 expression status. Furthermore, we investigated the impact of the HDIs SAHA and VPA on RelA/p65 activity in pancreatic cancer cell culture models.ResultsClass I HDACs were strongly expressed in a subset of pancreatic adenocarcinomas and high expression was significantly correlated with increased nuclear translocation of RelA/p65 (p = 0.024). The link of HDAC activity and RelA/p65 in this tumor entity was confirmed in vitro, where RelA/p65 nuclear translocation as well as RelA/p65 DNA binding activity could be markedly diminished by HDI treatment.ConclusionThe RelA/p65 inhibitory effects of SAHA and VPA in vitro and the close relationship of class I HDACs and RelA/p65 in vivo suggest that treatment with HDIs could serve as a promising approach to suppress NF-κB activity which in turn may lead to enhanced apoptosis and chemosensitization of pancreatic cancers.

Surgical strategies for treatment of malignant pancreatic tumors: extended, standard or local surgery?

Tumor related pancreatic surgery has progressed significantly during recent years. Pancreatoduodenectomy (PD) with lymphadenectomy, including vascular resection, still presents the optimal surgical procedure for carcinomas in the head of pancreas. For patients with small or low-grade malignant neoplasms, as well as small pancreatic metastases located in the mid-portion of pancreas, central pancreatectomy (CP) is emerging as a safe and effective option with a low risk of developing de-novo exocrine and/or endocrine insufficiency. Total pancreatectomy (TP) is not as risky as it was years ago and can nowadays safely be performed, but its indication is limited to locally extended tumors that cannot be removed by PD or distal pancreatectomy (DP) with tumor free surgical margins. Consequently, TP has not been adopted as a routine procedure by most surgeons. On the other hand, an aggressive attitude is required in case of advanced distal pancreatic tumors, provided that safe and experienced surgery is available. Due to the development of modern instruments, laparoscopic operations became more and more successful, even in malignant pancreatic diseases. This review summarizes the recent literature on the abovementioned topics.

Hepatitis C recurrence and fibrosis progression are not increased after living donor liver transplantation: A single-center study of 289 patients

Today, hepatitis C virus (HCV) is the leading cause for liver transplantation (LT) and viral recurrence is almost universal. It has been suggested that viral replication within the transplanted tissue might be increased in organs of reduced size such as LD grafts. In the current literature the data is controversial, with many studies lacking routine liver biopsies. We performed a retrospective analysis of 289 HCV‐LT (20 LD splits) patients receiving transplants between 1997 and 2005. Patient and organ survival, intensity of HCV recurrence, and fibrosis progression were analyzed with respect to deceased donor (DD) LT (DDLT) or living donor (LD) LT (LDLT). Organ and patient survival was significantly better for full‐size recipients than for split‐liver patients, with P = 0.037 for organ survival and P = 0.037 for patient survival; yet there were no significant differences when split‐liver patients with large hepatocellular carcinoma (HCC) beyond the Milan criteria (n = 3) were excluded from the analysis (P > 0.05). First year fibrosis progression was 1.29 in full‐size grafts and 1.07 in split‐livers (P = not significant). In conclusion, in our patient sample, intensity of HCV recurrence was not increased in LD graft recipients compared to full‐size recipients. Patient and organ survival were similar when patients with large HCC and early tumor recurrence were excluded from analysis. LDLT can therefore be advocated for HCV patients. Liver Transpl 13:687–692, 2007.

Role of IL28B polymorphism in the development of hepatitis C virus-induced hepatocellular carcinoma, graft fibrosis, and posttransplant antiviral therapy.

Background. The development of liver graft disease is partially determined by individual genetic background. Interleukin 28B (IL28B) is strongly suspected to be involved in susceptibility for hepatitis C virus (HCV) infection, inflammation, and antiviral treatment response before and after liver transplantation (LT). Currently, the role of IL28B polymorphism (rs12979860) in the development of hepatocellular carcinoma (HCC) is unclear, and only limited data are available on the course of HCV recurrence. Methods. One hundred sixty-seven HCV-positive patients after LT were genotyped for IL28B (C→T; rs12979860). Sixty-one patients with histologically confirmed HCC in the explanted liver were compared with 106 patients without HCC regarding IL28B genotypes. Among patients with HCC, IL28B genotypes were correlated with tumor histology and pretransplant &agr;-fetoprotein (AFP) levels. Furthermore, the role of IL28B polymorphism was evaluated regarding interferon-based treatment success and fibrosis progression after LT. Results. The prevalence of HCC in explanted livers was significantly higher among patients with TT genotype, suggesting a protective role of the C allele in HCC development (P=0.041). Median AFP level was closely to significance higher in the presence of T allele (P=0.052). Significant differences in IL28B genotype distribution were detected between AFP-negative and AFP-positive HCCs (<15 &mgr;g/L vs. >15 &mgr;g/L; P=0.008). Although no impact could be observed regarding acute cellular rejection (P=0.940), T allele was significantly associated with antiviral therapy failure (P=0.028) and faster development of advanced fibrosis (P=0.017) after LT. Conclusion. IL28B polymorphism seems to be involved in the development of HCV-induced HCC and in the course of HCV recurrence after LT. T allele may be regarded as a genetic risk factor for HCV-related carcinogenesis, posttransplant fibrosis progression, and antiviral therapy failure.