Sven H. Loosen

RIPK1 Suppresses a TRAF2-Dependent Pathway to Liver Cancer

Receptor-interacting protein kinase 1 (RIPK1) represents an essential signaling node in cell death and inflammation. Ablation of Ripk1 in liver parenchymal cells (LPC) did not cause a spontaneous phenotype, but led to tumor necrosis factor (TNF)-dependent hepatocyte apoptosis and liver injury without affecting inducible nuclear factor κB (NF-κB) activation. Loss of Ripk1 induced the TNF-dependent proteasomal degradation of the E3-ligase, TNF receptor-associated factor 2 (TRAF2), in a kinase-independent manner, thereby activating caspase-8. Moreover, loss of both Ripk1 and Traf2 in LPC not only resulted in caspase-8 hyperactivation but also impaired NF-κB activation, promoting the spontaneous development of hepatocellular carcinoma. In line, low RIPK1 and TRAF2 expression in human HCCs was associated with an unfavorable prognosis, suggesting that RIPK1 collaborates with TRAF2 to inhibit murine and human hepatocarcinogenesis.

Current and future biomarkers for pancreatic adenocarcinoma

Although pancreatic cancer is only the twelfth most common type of cancer in the world, it features a very unfavorable prognosis. The mortality rate almost equals the incidence rate, corroborating the very poor prognosis of pancreatic cancer. The 5-year survival rate for all stages of pancreatic ductal adenocarcinoma is only 7%. Surgical resection represents the only potentially curative treatment option for pancreatic ductal adenocarcinoma patients but is often not feasible due to the advanced stage of the disease upon diagnosis. For advanced disease, palliative chemotherapy is the treatment of choice although the regimens available to date are untargeted and have extensive side-effect profiles, making them unsuitable for patients with a low performance status. For this reason, early detection of pancreatic cancer is essential in order to provide patients with an optimal therapeutic approach. Up to the present day, carbohydrate antigen 19-9 is the only diagnostic marker approved by the U.S. Food and Drug Administration but its diagnostic potential is limited due to its restricted sensitivity and specificity, supporting the urgent need for novel biomarkers. In addition, prognostic and treatment-predictive biomarkers might provide essential information regarding personalized treatment decisions for individual patients. In this article, we aim to review current and future diagnostic, prognostic, and treatment-predictive biomarkers for pancreatic cancer.

Role of circulating microRNAs in liver diseases

MicroRNAs (miRNAs) are small RNAs regulate gene expression by inhibiting the turnover of their target mRNAs. In the last years, it became apparent that miRNAs are released into the circulation and circulating miRNAs emerged as a new class of biomarkers for various diseases. In this review we summarize available data on the role of circulating miRNAs in the context of acute and chronic liver diseases including hepatocellular and cholangiocellular carcinoma. Data from animal models are compared to human data and current challenges in the field of miRNAs research are discussed.

Elevated levels of circulating osteopontin are associated with a poor survival after resection of cholangiocarcinoma

BACKGROUND & AIMS Cholangiocarcinoma (CCA) represents a primary hepatic malignancy with incidence and mortality rising globally. Surgical treatment has remained the only potentially curative treatment option, but it is still unclear which patients benefit most from extended liver surgery, highlighting the need for new pre-operative stratification strategies. Osteopontin is a secreted extracellular glyco-phosphoprotein that has been associated with inflammation, metabolic disorders and cancer. Here, we examined the potential of circulating osteopontin serum levels as a diagnostic or prognostic biomarker in patients with CCA undergoing extended liver surgery. METHODS Osteopontin expression levels were analysed in human and murine CCA tumour samples, using semi-quantitative reverse transcriptase PCR and immunohistochemistry. Osteopontin serum concentrations were measured by enzyme-linked immunosorbent assay in 107 patients with CCA undergoing elective tumour resection as well as 55 healthy controls. Results were correlated with clinical data. RESULTS Correlating with an upregulation in CCA tumour cells and the tumour stroma, serum levels of osteopontin were elevated in patients with cholangiocarcinoma compared to healthy controls and patients with primary sclerosing cholangitis. Importantly, pre- and postoperative elevations of osteopontin showed a striking association with poor postoperative survival. CONCLUSIONS Serum osteopontin concentrations represent a promising prognostic biomarker in patients resectable CCA which could help to guide preoperative treatment decisions and to identify patients that will particularly benefit from extended liver surgery. Lay summary: Extended liver surgery is the only potentially curative treatment for patients with cholangiocarcinoma (CCA/biliary cancer), but it is currently unclear which patients benefit most from surgery. Detecting serum levels of osteopontin - a specific secreted glycoprotein involved in multiple human diseases - in CCA patients might help to identify those patients that particularly benefit from tumour resection.

MiR-223 represents a biomarker in acute and chronic liver injury

BACKGROUND Dysregulation of miRNAs has been described in tissue and serum from patients with acute and chronic liver diseases. However, only little information on the role of miR-223 in the pathophysiology of acute liver failure (ALF) and liver cirrhosis is available. METHODS We analysed cell and tissue specific expression levels as well as serum concentrations of miR-223 in mouse models of acute (hepatic ischaemia and reperfusion, single CCl4 injection) and chronic (repetitive CCl4 injection, bile duct ligation (BDL)) liver diseases. Results were validated in patients and correlated with clinical data. The specific hepatic role of miR-223 was analysed by using miR-223-/- mice in these models. RESULTS miR-223 expression was significantly dysregulated in livers from mice after induction of acute liver injury and liver fibrosis as well as in liver samples from patients with ALF or liver cirrhosis. In acute and chronic models, hepatic miR-223 up-regulation was restricted to hepatocytes and correlated with degree of liver injury and hepatic cell death. Moreover, elevated miR-223 expression was reflected by significantly higher serum levels of miR-223 during acute liver injury. However, functional in vitro and in vivo experiments revealed no differences in the degree of liver cell death and liver fibrosis as miR-223-/- mice behaved identical with wild-type (wt) mice in all tested models. CONCLUSION miR-223 represents a promising diagnostic marker in a panel of serum markers of liver injury. Together with previously published data, our results highlight that the role of miR-223 in the pathophysiology of the liver is complex and needs further analysis.

CEA but not CA19-9 is an independent prognostic factor in patients undergoing resection of cholangiocarcinoma

Cholangiocarcinoma (CCA) represents a rare form of primary liver cancer with increasing incidence but dismal prognosis. Surgical treatment has remained the only potentially curative treatment option, but it remains unclear which patients benefit most from liver surgery, highlighting the need for new preoperative stratification strategies. In clinical routine, CA19-9 represents the most widely used tumor marker in CCA patients. However, data on the prognostic value of CA19-9 in CCA patients are limited and often inconclusive, mostly due to small cohort sizes. Here, we investigated the prognostic value of CA19-9 in comparison with other standard laboratory markers in a large cohort of CCA patients that underwent tumor resection. Of note, while CA19-9 and CEA were able to discriminate between CCA and healthy controls, CEA showed a higher accuracy for the differentiation between CCA and patients with primary sclerosing cholangitis (PSC) compared to CA19-9. Furthermore, patients with elevated levels of C-reactive protein (CRP), CA19-9 or CEA showed a significantly impaired survival in Kaplan-Meier curve analysis, but surprisingly, only CEA but not CA19-9 represented an independent predictor of survival in multivariate Cox-regression analysis. Our data suggest that CEA might help to identify CCA patients with an unfavourable prognosis after tumor resection.

Serum levels of S100A6 are unaltered in patients with resectable cholangiocarcinoma

BackgroundElevated expression levels of S100A6, a calcium-binding low-molecular-weight protein, were demonstrated in various malignancies. Moreover, increased serum levels of S100A6 were suggested as a novel biomarker for various inflammatory and malignant diseases including lung and gastric cancer. However, up to now, serum concentrations of S100A6 have not been analyzed in patients with cholangiocarcinoma (CCA).MethodsS100A6 mRNA expression levels were analyzed in human and murine CCA tumor samples, using semi-quantitative reverse transcriptase PCR. S100A6 serum concentrations were measured using an enzyme-linked immunosorbent assay in 112 patients with CCA referred to surgery for curative resection and were compared to those of 42 healthy controls. Results were correlated with clinical data.ResultsS100A6 mRNA expression levels were significantly up-regulated in tumor samples of CCA patients and in tumor tissue of a CCA mouse model. In contrast, serum levels of S100A6 were not significantly altered in patients with CCA compared to healthy controls. Whereas no differences became apparent within the different clinical subgroups of CCA, patients with primary sclerosing cholangitis (PSC)-based CCA displayed higher levels of S100A6 compared to the other patients. Nevertheless, patients with higher S100A6 serum concentrations showed a trend towards an impaired prognosis compared to patients with lower levels. Finally, within our cohort of patients both the diagnostic and prognostic potentials of S100A6 were similar to those of the clinically established biomarkers CEA and CA19-9.ConclusionAlthough S100A6 was expressed at significantly higher levels in human and murine CCA tumor samples, S100A6 serum levels were not regulated in patients with CCA and are thus not suitable for diagnosis of CCA. However, CCA-patients with elevated S100A6 displayed a trend toward an impaired prognosis compared to patients with lower S100A6 levels, supporting its further evaluation as a prognostic biomarker in CCA.

Testis-sparing surgery for benign testicular masses – diagnostics and therapeutic approaches

Purpose: Small benign testicular masses are often misinterpreted as germ cell tumors and immediate inguinal orchiectomy is performed. We analyzed the diagnostic and therapeutic workup of testicular masses to improve preoperative stratification algorithms. Materials and Methods: We performed a retrospective, single center analysis of the records of 522 patients diagnosed with primary testicular masses of unknown malignant potential. Results: A total of 28 patients (5%) showed a primary benign tumor after resection, including Leydig cell tumors in 9 (32%), epidermoid cysts in 9 (32%), adenomatoid tumors in 8 (29%) and Sertoli cell tumors in 2 (7%). The median volume of benign tumors was significantly less than that of malignant tumors (0.75 cm3, range 0.1 to 2.1 vs 15, range 4.5–39.9, p ≤0.001). At a cutoff of 2.8 cm3 tumor volume most accurately differentiated between benign and malignant disease, and it was a predictor of malignancy with 83% sensitivity and 89% specificity (OR 1.389, 95% CI 1.035–1.864, p = 0.029). Symptom duration in patients with benign tumors was significantly longer (365 days, range 25.5 to 365 vs 20, range 7 to 42, p ≤0.001). Also, tumor markers were unaltered in benign lesions. In patients with benign tumors significantly more fertility disorders or cryptorchidism were found (p ≤0.001) as well as a tendency toward lower testosterone (3.9 &mgr;g/l, range 0.9 to 4.9 vs 5.3, range 3.5 to 6.8, p = 0.084). Testis sparing surgery was performed in 22 of all patients (79%) with benign tumors. There was no case of relapse during followup. Conclusions: Nongerm cell tumors should be considered when small testicular masses have a volume of less than 2.8 cm3 and there are hormone disorders or normal tumor markers. Immediate orchiectomy should be avoided, favoring testis sparing surgery.

Non–Guideline-concordant Treatment of Testicular Cancer Is Associated With Reduced Relapse-free Survival

Introduction The management of testicular cancer (TC) requires a complex multimodal therapeutic approach. Despite the availability of regularly updated guidelines, non–guideline‐concordant treatment of TC still occurs. The purpose of the present study was to evaluate the compliance patterns in diagnosis and therapy and their potential effects on patient outcomes with respect to the guidelines of the European Association of Urology. Patients and Methods We performed a retrospective analysis of 131 patients diagnosed with TC who had been referred to our department from September 2015 to October 2016. Patient characteristics were compared with European Association of Urology guideline recommendations. Results Of the 131 primary treated patients, 23 (18%) had received a non–guideline‐concordant treatment. The most common error was undertreatment (n = 12; 52%), mainly due to missing chemotherapy cycles. Overtreatment occurred in 30% of patients (n = 7); however, inappropriate treatment (n = 2; 9%) and misdiagnosis (n = 2; 9%) were rarely observed. In salvage therapy, non–guideline concordant treatment was observed less frequently compared to patients receiving primary therapy (12% vs. 18%). Of the 131 patients, 35 developed a relapse, 23 of whom were treated correctly and 6 of whom were undertreated. Undertreatment of patients resulted in significantly reduced relapse‐free survival compared with guideline‐concordant management in primary treated patients (P = .005). Conclusion Despite the standardization of treatment by interdisciplinary guidelines, its integration into daily practice remains limited. Undertreatment of TC patients is associated with significantly reduced relapse‐free survival and should thus be avoided. Micro‐Abstract The treatment of testicular cancer (TC) requires a multimodal approach. We retrospectively evaluated the diagnostic work‐up, treatment, and outcomes of 131 patients with respect to the European Association of Urology guidelines. Of 131 patients, 18% had received non–guideline‐concordant treatment, with undertreatment having a negative effect on relapse‐free survival. Thus, implementation of guidelines is needed to decrease the mortality of TC.

Elevated serum levels of bone sialoprotein during ICU treatment predict long-term mortality in critically ill patients

Bone sialoprotein (BSP), a member of the SIBLINGs (for Small Integrin-Binding LIgand, N-linked Glycoproteins) family, has recently be associated to inflammatory and infectious diseases. We therefore measured BSP concentrations in 136 patients at admission to the intensive care unit (ICU) and 3 days of ICU. BSP levels were compared to 36 healthy blood donors and correlated to clinical data. In these analysis, BSP serum levels were strongly elevated at the time point of admission to the ICU when compared to healthy controls. Moreover BSP concentrations were significantly elevated after 3 days of treatment on the intensive care unit. A further increase in BSP levels was detected in patients with higher APACHE-II-scores and in patients with septic disease. While in most patients, BSP levels decreased during the first three days of treatment on a medical ICU, patients with persistently elevated BSP levels displayed an unfavorable outcome. In these patients, persistently elevated BSP concentrations were a superior predictor of mortality than established indicators of patient´ prognosis such as the SAPS2 or the APACHE-II score. In summary, our data argue for a novel utility for BSP as a biomarker in patients treated on a medical ICU.