Target Selection for T-Cell Therapy in Epithelial Ovarian Cancer: Systematic Prioritization of Self-Antigens.

Adoptive T cell-receptor therapy (ACT) could represent a promising approach in the targeted treatment of epithelial ovarian cancer (EOC). However, the identification of suitable tumor-associated antigens (TAAs) as targets is challenging. We identified and prioritized TAAs for ACT and other immunotherapeutic interventions in EOC. A comprehensive list of pre-described TAAs was created and candidates were prioritized, using predefined weighted criteria. Highly ranked TAAs were immunohistochemically stained in a tissue microarray of 58 EOC samples to identify associations of TAA expression with grade, stage, response to platinum, and prognosis. Preselection based on expression data resulted in 38 TAAs, which were prioritized. Along with already published Cyclin A1, the TAAs KIF20A, CT45, and LY6K emerged as most promising targets, with high expression in EOC samples and several identified peptides in ligandome analysis. Expression of these TAAs showed prognostic relevance independent of molecular subtypes. By using a systematic vetting algorithm, we identified KIF20A, CT45, and LY6K to be promising candidates for immunotherapy in EOC. Results are supported by IHC and HLA-ligandome data. The described method might be helpful for the prioritization of TAAs in other tumor entities.

High rate of Ki-67 increase in entero-pancreatic NET relapses after surgery with curative intent.

Neuroendocrine neoplasms (NENs) present with advanced disease at diagnosis in up to 28% of cases, precluding the possibility of curative-intent surgery. Histopathological heterogeneity of this disease can be observed inter-individually as well as intra-individually during disease course. The present study aimed to assess the frequency of Ki-67 change after radical surgery, in a series of patients with radically resected entero-pancreatic neuroendocrine tumors (EP-NETs). We present the analysis of a multicenter, retrospective, series of EP-NETs G1-G2 recurring after radical resection and with histological re-evaluation at disease recurrence (DR). The primary endpoint was the description of Ki-67 change at DR compared to time of surgery. The secondary endpoint was assessment of recurrence-free survival (RFS) rates. In total, 47 patients had a second histological evaluation and could be included in the present study. Median Ki-67 at surgery was 3% (range 1-15%) but, at DR, a significant increase in the value was observed (7%, range 1-30%; p < .01) and involved 66.0% of cases, with a corresponding increase in tumor grading in 34.0% (p = .05). Median RFS of the overall population was 40 months, and was worse when Ki-67 increased at DR vs. stable Ki-67 value (36 vs. 61 months, respectively; p = .02). In conclusion, in more than half of the cases with relapse after radical surgery, a higher proliferative index with a potentially more aggressive potential was observed. Therefore, histological reassessment should be considered on DR because tailored therapeutic strategies may be required for these patients.

Immunoprofiling in Neuroendocrine Neoplasms Unveil Immunosuppressive Microenvironment.

Checkpoint inhibitors have shown promising results in a variety of tumors; however, in neuroendocrine tumors (NET) and neuroendocrine carcinomas (NEC), low response rates were reported. We aimed herein to investigate the tumor immune microenvironment in NET/NEC to determine whether checkpoint pathways like programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) might play a role in immune escape and whether other escape mechanisms might need to be targeted to enable a functional antitumor response. Forty-eight NET and thirty NEC samples were analyzed by immunohistochemistry (IHC) and mRNA immunoprofiling including digital spatial profiling. Through IHC, both NET/NEC showed stromal, but less intratumoral CD3+ T cell infiltration, although this was significantly higher in NEC compared to NET. Expression of PD1, PD-L1, and T cell immunoglobulin and mucin domain-containing protein 3 (TIM3) on immune cells was low or nearly absent. mRNA immunoprofiling revealed low expression of IFNγ inducible genes in NET and NEC without any spatial heterogeneity. However, we observed an increased mRNA expression of chemokines, which attract myeloid cells in NET and NEC, and a high abundance of genes related to immunosuppressive myeloid cells and genes with immunosuppressive functions like CD47 and CD74. In conclusion, NET and NEC lack signs of an activation of the adaptive immune system, but rather show abundance of several immunosuppressive genes that represent potential targets for immunomodulation.

Efficacy and Safety of CAP7.1 as Second-Line Treatment for Advanced Biliary Tract Cancers: Data from a Randomised Phase II Study.

CAP7.1 is a novel topoisomerase II inhibitor, converted to active etoposide via carboxylesterase 2 (CES2), with signals of efficacy in treatment-refractory solid tumours. In a Phase II trial, 27 patients with advanced biliary tract cancers (BTC) were randomised 1:1 to CAP7.1 plus best supportive care (BSC), or BSC alone, with crossover to CAP7.1 upon disease progression. The primary objective was disease control rate (DCR) following 28-day cycles of CAP7.1 (200/150 mg/m2; iv), or BSC until progression. Secondary objectives included progression-free survival (PFS), time-to-treatment failure (TTF), overall survival (OS) and safety. Fourteen patients received CAP7.1 and 13 BSC. DCR favoured CAP7.1 vs. BSC (50% vs. 20%; treatment difference: 30%, 95%CI -18.44, 69.22, full analysis set [FAS]), with disease progression in 40% vs. 70%, respectively. Significantly longer median PFS was achieved for CAP7.1 vs. BSC: 66 vs. 39 days, respectively (hazard ratio [HR] 0.31; 95%CI 0.11, 0.86; p = 0.009; FAS). Similar trends were observed for TTF and OS. CES2-positive patients had longer median PFS (158 vs. 56 days) and OS (228 vs. 82 days) vs. CES2-negative patients. Adverse events were predictable, dose-dependent and consistent with those previously observed with etoposide. These efficacy and safety findings in second-line BTC warrant further clinical investigation of CAP7.1.

Dual versus single vessel normothermic ex vivo perfusion of rat liver grafts using metamizole for vasodilatation.

BACKGROUND: Normothermic ex vivo liver perfusion (NEVLP) is a promising strategy to increase the donor pool in liver transplantation. Small animal models are essential to further investigate questions regarding organ preservation and reconditioning by NEVLP. A dual vessel small animal NEVLP (dNEVLP) model was developed using metamizole as a vasodilator and compared to conventional portovenous single vessel NEVLP (sNEVLP). METHODS: Livers of male Wistar rats were perfused with erythrocyte-supplemented culture medium for six hours by either dNEVLP via hepatic artery and portal vein or portovenous sNEVLP. dNEVLP was performed either with or without metamizole treatment. Perfusion pressure and flow rates were constantly monitored. Transaminase levels were determined in the perfusate at the start and after three and six hours of perfusion. Bile secretion was monitored and bile LDH and GGT levels were measured hourly. Histopathological analysis was performed using liver and bile duct tissue samples after perfusion. RESULTS: Hepatic artery pressure was significantly lower in dNEVLP with metamizole administration. Compared to sNEVLP, dNEVLP with metamizole treatment showed higher bile production, lower levels of transaminases during and after perfusion as well as significantly lower necrosis in liver and bile duct tissue. Biochemical markers of bile duct injury showed the same trend. CONCLUSION: Our miniaturized dNEVLP system enables normothermic dual vessel rat liver perfusion. The administration of metamizole effectively ameliorates arterial vasospasm allowing for six hours of dNEVLP, with superior outcome compared to sNEVLP.

Efficacy and Toxicity of 5-Fluorouracil-Oxaliplatin in Gastroenteropancreatic Neuroendocrine Neoplasms.

OBJECTIVES: The objective of this study was to investigate the efficacy and tolerability of 5-fluorouracil-oxaliplatin (FOLFOX) in advanced gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs). METHODS: Retrospective analysis of consecutive 72 advanced GEP-NENs treated with FOLFOX between 2005 and 2016 at a single German referral center for NENs was performed. We assessed treatment response by response evaluation criteria in solid tumors 1.0 criteria, progression-free survival by Kaplan-Meyer method, and risk factor analysis by Cox-regression model. RESULTS: Patients were 44.5% G1/G2, 55.5% G3, receiving a median of 7 treatment cycles (range, 2-21), and had a median of 18 months of follow-up (range, 3-111 months). Disease control was achieved in 75.0% of cases but 91.3% in the 23 patients receiving FOLFOX as first line (P = 0.04). Median progression-free survival of the overall population was 8 months. A better outcome was significantly related to treatment duration (P = 0.02) and grade of histological differentiation for G3 patients (well differentiated vs poorly differentiated, P = 0.03). Adverse events occurred in 88.8% of patients, mostly grade 1 and 2 hematotoxicity and chemotherapy-induced peripheral sensory neuropathy (84.1% and 50.0% of patients, respectively). CONCLUSIONS: Our results support FOLFOX as therapeutic option in advanced GEP-NENs with poor prognosis, either at first or further therapy line. Longer duration of therapy was associated with a more durable benefit.

Radical intended surgery for highly selected stage IV neuroendocrine neoplasms G3.

BACKGROUND: Stage IV gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs) G3 are the NENs with the worst prognosis. According to ENETS guidelines, platinum-based chemotherapy is the standard treatment for this population. Surgery is only considered in highly selected "resectable" NENs with usually lower Ki67. However, the role of surgery with curative intent has been poorly investigated. OBJECTIVE: To describe, in a retrospective series of stage IV GEP-NENs G3, overall survival (OS) and recurrence-free survival (RFS) rates after curatively intended surgery. METHODS: Multicenter analysis of stage IV GEP-NENs G3 receiving radical resection (R0/R1) from 2007 to 2017, with minimum post-surgical follow-up time of 3 months. RESULTS: Fifteen patients from 6 NEN referral centers, with median follow-up of 29 months (8-86), were included. Eight cases had a neuroendocrine carcinoma (NEC) and 7 a neuroendocrine tumor G3 (NET G3). Median OS after radical surgery was 59 months. All patients recurred, with a median RFS of 8 months. CONCLUSIONS: Radical surgery might be considered for highly selected stage IV GEP-NENs G3. Larger series are needed to confirm these results.

Prognostic Significance of Somatostatin Receptor Heterogeneity in Progressive Neuroendocrine Tumor Treated with Lu-177 DOTATOC or Lu-177 DOTATATE.

AIM: One of the primary prerequisites for peptide receptor radionuclide therapy (PRRT) in patients with neuroendocrine tumors (NET) is the presence of somatostatin receptors (SSTR) on NET cells. NET are highly heterogeneous and an individual patient as well as separate metastases can harbor cells with different clones, which influence the SSTR expression on NET cells. With this background we looked into our institutional database to assess the prognostic significance of quality of SSTR expression on SSTR PET/CT imaging in patients treated with at least two cycles of Lu-177 DOTATOC or Lu-177 DOTATATE. METHOD: Clinical reports and images from 65 (25 females, 40 males; 65 ± 11 years old) patients with progressive grade 1 or grade 2 NET with 2-5 therapy cycles of PRRT with an average administered dose of 6.6 ± 0.97 GBq Lu-177 DOTATOC or Lu-177 DOTATATE were analyzed. All patients were examined with baseline Ga-68 DOTATATE or Ga-68 DOTATOC PET/CT (PET). Quality of SSTR expression as a measure of heterogeneity on indexed lesions was assessed visually. Patients were followed for a median duration of 25 months after the first PRRT (range 5-77 months). RESULTS: A total of 70% of the patients received three or more therapy cycles. Twenty-six patients (40%) were treated with PRRT as first or second line while 39 (60%) as third line or more. SSTR expression was heterogeneous in 28 (44.4%) and homogeneous in 35 (55.6%) patients. Disease stabilization could be achieved in 23 patients (35.4%), whereas 17 (26.1%) showed partial remission and 25 patients (38.5%) had disease progression. Median OS was not reached. The 24-month survival rate of the whole study cohort was 83%. In univariate analyses, factors influencing OS were carcinoid heart disease, carcinoid syndrome and quality of SSTR expression (p < 0.05). Patients with heterogeneous SSTR expression on target lesions had a significantly lower OS (p = 0.01). Median time to progression in total patient population was found to be 40 months. Patients with heterogeneous SSTR expression on target lesions had significantly lower TTP (26 months vs 54 months log Rank p = 0.013). By multivariate analyses, quality of SSTR was found to be the only prognostic factor for OS (p = 0.04; HR = 3.68) and also for TTP (p = 0.03; HR = 3.09). CONCLUSION: Visual assessment of SSTR heterogeneity has both predictive and prognostic value in progressive grade 1 or grade 2 NET patients undergoing PRRT.

Peritoneal Carcinomatosis in Gastro-Entero-Pancreatic Neuroendocrine Neoplasms: Clinical Impact and Effectiveness of the Available Therapeutic Options.

BACKGROUND: Peritoneal carcinomatosis (PC) can affect the quality of life of patients with gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs). Peritoneal disease control by medical therapies in these patients has been poorly investigated Objectives: To describe, in a consecutive series of GEP-NENs, the clinical impact of PC and to report the effectiveness of available treatments in PC control. METHODS: A retrospective, monocenter analysis was performed of 135 GEP-NENs (1993-2016) with at least a 12-month follow-up. Peritoneal disease progression was defined as detection of a significant increase in size or appearance of new implants by imaging. RESULTS: A total of 62.9% of cases had diffuse PC (involving at least 2 abdominal quadrants). According to WHO 2017 classification, cases were 42.3% neuroendocrine tumors NET-G1, 45.5% NET-G2, 6.5% NET-G3, 4.9% neuroendocrine carcinomas NEC-G3, and 0.8% mixed neuroendocrine-nonneuroendocrine neoplasms. Bowel obstruction occurred in 30 (22.2%) patients mainly depending on size of peritoneal implants (HR: 1.10; 95% CI: 1.02-1.20; p = 0.01). Patients with diffuse PC treated with peptide receptor radionuclide therapy (PRRT) showed peritoneal progression in 37.5% of cases, and bowel obstruction or ascites in 28.1%. Better peritoneal disease control was observed in cases receiving somatostatin analogs at first-line therapy, probably due to a less aggressive disease behavior for these patients. CONCLUSIONS: Bowel obstruction is not uncommon in GEP-NENs with PC. PRRT should be adopted with caution in GEP-NENs with diffuse PC, but larger series are needed to confirm these data.

Peritoneal and upper genital tract tuberculosis.

Aim To present diagnostic and therapeutic possibilities for genital and peritoneal tuberculosis, mimicking to other pathological conditions, mainly, ovarian cancer. Methods Transabdominal and transvaginal ultrasound, computerized tomography, Ca125 and HE 4, ROMA- index (Risk of Ovarian Maligancy Algorithm index) and diagnostic laparoscopy were performed in order to diagnose genital tuberculosis in a female patient. Results: A 23-year-old woman from Morocco presented with intermitting abdominal pain, unintentional weight loss and primary infertility. There was no positive family history for breast or ovarian cancer and no history of previous tuberculosis (TB). Elevated CA-125 level, HE 4 normal, ROMA-Index of 13.2 % suggested high risk for epithelial ovarian cancer (EOC). Ultrasound revealed free fluid, dilated fallopian tubes and a cystic mass near the right ovary. Suspecting fallopian tube or ovarian cancer, we performed exploratory laparoscopy, revealing adhesions, multiple miliary nodes and dilated fallopian tubes. Histological investigation revealed granulomatous abscessing salpingitis with suspicion of genital TB, so antituberculous therapy was administered with success. Conclusion Female genital tuberculosis is very rare but important in differential diagnosis and should be kept in mind regarding suspected fallopian tube or ovarian carcinoma to prevent women from extensive surgery. An algorithm for possible differentiation between peritoneal/female genital TB and EOC may be helpful in clinical setting.

Development of a Rat Liver Machine Perfusion System for Normothermic and Subnormothermic Conditions.

Ex vivo liver machine perfusion (MP) is a promising alternative for preservation of liver grafts from extended criteria donors. Small animal models can be used to evaluate different perfusion conditions. We here describe the development of a miniaturized ex vivo MP system for rat liver grafts, evaluating cell-free and erythrocyte-based perfusion solutions, subnormothermic and normothermic temperatures, and dialysis. A perfusion chamber was designed after a suitable liver position was identified. Normothermic ex vivo liver perfusion (NEVLP) required supplementation of erythrocytes to reduce cell damage. Perfusion with erythrocytes led to rising potassium levels after 12 h (NEVLP, 16.2 mM, interquartile range [IQR]: 5.7 and subnormothermic ex vivo liver perfusion [SNEVLP], 12.8 mM, IQR: 3.5), which were normalized by dialysis using a laboratory dialysis membrane (NEVLP, 6.2 mM, IQR: 0.5 and SNEVLP, 5.3 mM, IQR: 0.1; p = 0.004). Livers treated with NEVLP conditions showed higher bile production (18.52 mg/h/g, IQR: 8.2) compared to livers perfused under SNEVLP conditions (0.4 mg/h/g, IQR: 1.2, p = 0.01). Reducing the perfusion volume from 100 to 50 mL allowed for higher erythrocyte concentrations, leading to significantly lower transaminases (15.75 U/L/mL, IQR: 2.29 vs. 5.97 U/L/mL, IQR: 18.07, p = 0.002). In conclusion, a well-designed perfusion system, appropriate oxygen carriers, dialysis, and miniaturization of the perfusion volume are critical features for successful miniaturized ex vivo liver MP. Impact Statement Ex vivo liver machine perfusion (MP) is an emerging preservation alternative to static cold storage. Even though clinical studies have shown benefits for extended criteria donor grafts, standardized systems for perfusion of rat liver grafts are not available, which are inevitable for large-scaled studies on liver reconditioning by ex vivo MP. We here comprehensively describe the development of an ex vivo rat liver perfusion system that can be used as modular setting in various approaches of liver MP. We describe pitfalls and techniques that might be of interest when establishing such perfusion systems for basic and translational research.

Surgery with Radical Intent: Is There an Indication for G3 Neuroendocrine Neoplasms?

BACKGROUND: While platinum-based chemotherapy represents the standard treatment for advanced grade 3 (G3) neuroendocrine neoplasms (NENs) according to the European Neuroendocrine Tumor Society guidelines, the role of radical-intended surgery in these patients, as well as the use of adjuvant chemotherapy, are still controversial. The aim of the present work is to describe, in a retrospective series of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) G3, the overall survival (OS) rate and risk factors for death after radical surgery. Secondary aims are the description of median recurrence-free survival (RFS) and of the role of adjuvant chemotherapy. PATIENTS AND METHODS: Multicenter analysis of a series of stage I-III GEP-NEN G3 patients receiving radical surgery (R0/R1) with/without adjuvant chemotherapy was performed. RESULTS: Sixty patients from eight neuroendocrine tumor (NET) referral centers, with median follow-up of 23 months (5-187 months) were evaluated. While 28.6% of cases had NET G3, 71.4% had neuroendocrine carcinoma G3 (NEC G3). The 2-year OS rate after radical surgery was 64.5%, with a statistically significant difference in terms of Ki67 threshold (cut-off 55%, P = 0.03) and tumor differentiation (NEC G3 vs. NET G3, P = 0.03). Median RFS after radical surgery was 14 months, and 2-year RFS rate was 44.9%. Use of adjuvant chemotherapy provided no benefit in terms of either OS or RFS in this series. CONCLUSIONS: Surgery with radical intent might represent a valid option for GEP-NEN G3 patients with locoregional disease, especially with Ki67 value ≤ 55%.

Hepatic CYP1A2 activity in liver tumors and the implications for preoperative volume-function analysis.

Dynamic liver function assessment by the [13C]methacetin maximal liver function capacity (LiMAx) test reflects the overall hepatic cytochrome P-450 (CYP) 1A2 activity. One proven strategy for preoperative risk assessment in liver surgery includes the combined assessment of the dynamic liver function by the LiMAx test, the volumetric analysis of the liver, and calculation of future liver remnant function. This so-called volume-function analysis assumes that the remaining CYP1A2 activity in any tumor lesion is zero. The here presented study aims to assess the remaining CYP1A2 activities in different hepatic tumor lesions and its consequences for the preoperative volume-function analysis in patients undergoing liver surgery. The CYP1A2 activity analysis of neoplastic lesions and adjacent nontumor liver tissue from resected tumor specimens revealed a significantly higher CYP1A2 activity (median, interquartile range) in nontumor tissues (35.5, 15.9-54.4 µU/mg) compared with hepatocellular adenomas (7.35, 1.2-32.5 µU/mg), hepatocellular carcinomas (0.18, 0.0-2.0 µU/mg), or colorectal liver metastasis (0.17, 0.0-2.1 µU/mg). In nontumor liver tissue, a gradual decline in CYP1A2 activity with exacerbating fibrosis was observed. The CYP1A2 activity differences were also reflected in CYP1A2 protein signals in the assessed hepatic tissues. Volume-function analysis showed a minimal deviation compared with the current standard calculation for hepatocellular carcinomas or colorectal liver metastasis (<1% difference), whereas a difference of 11.9% was observed for hepatocellular adenomas. These findings are important for a refined preoperative volume-function analysis and improved surgical risk assessment in hepatocellular adenoma cases with low LiMAx values. NEW & NOTEWORTHY The cytochrome P-450 (CYP) 1A2-dependent maximal liver function capacity test reflects the overall functional capacity of the liver. To which extent hepatocellular tumors harbor CYP1A2 activity and thus contribute to the maximal liver function capacity test outcome is unknown. We here show that hepatocellular adenomas but not hepatocellular carcinomas or colorectal liver metastasis contain significant residual CYP1A2 activity. These findings are important for an improved preoperative volume-function analysis and an accurate surgical risk assessment in hepatocellular adenoma cases.

Prognostic Impact of Carboxylesterase 2 in Cholangiocarcinoma.

Carboxylesterase 2 (CES2) is instrumental for conversion of ester-containing prodrugs in cancer treatment. Novel treatment strategies are exceedingly needed for cholangiocarcinoma (CCA) patients. Here, we assessed CES2 expression by immunohistochemistry in a CCA cohort comprising 171 non-liver fluke associated, intrahepatic (n = 72) and extrahepatic (perihilar: n = 56; distal: n = 43) CCAs. Additionally, 80 samples of high-grade biliary intraepithelial neoplastic tissues and 158 corresponding samples of histological normal, non-neoplastic biliary tract tissues were included. CES2 expression was highest in non-neoplastic biliary tissue and significantly decreased in CCA. Patients showing any CES2 expression in tumor cells had a significantly better overall survival compared to negative cases (p = 0.008). This survival benefit was also maintained after stratification of CES2-positive cases, by comparing low, medium and high CES2 expression levels (p-trend = 0.0006). Evaluation of CCA subtypes showed the survival difference to be restricted to extrahepatic tumors. Correlation of CES2 expression with data of tumor-infiltrating immune cells showed that particularly CD8+ T cells were more frequently detected in CES2-positive CCAs. Furthermore, treatment of CCA cell lines with the prodrug Irinotecan reduced cell viability, increased cytotoxicity and modulated inflammatory gene expression. In conclusion, reduced CES2 expression is associated with poor outcome and low CD8+ T cell infiltration in CCA patients. Further clinical studies could show, whether CES2 expression may serve as a predictive marker in patients treated with prodrugs converted by CES2.

Non-invasive structure-function assessment of the liver by 2D time-harmonic elastography and the dynamic Liver MAximum capacity (LiMAx) test.

BACKGROUND AND AIM: Accurate assessment of structural and functional characteristics of the liver could improve the diagnosis and the clinical management of patients with chronic liver diseases. However, the structure-function relationship in the progression of chronic liver disease remains elusive. The aim of this study is the combined measurement of liver function by the 13 C-methacetin Liver MAximum capacity (LiMAx) test and tissue-structure related stiffness by 2D time-harmonic elastography for the assessment of liver disease progression. METHODS: LiMAx test and time-harmonic elastography were applied, and the serological scores fibrosis 4 index and aspartate aminotransferase to platelet ratio index were calculated in patients with chronic liver diseases (n = 75) and healthy control subjects (n = 22). In 47 patients who underwent surgery, fibrosis was graded by histological examination of the resected liver tissue. RESULTS: LiMAx values correlated negatively with liver stiffness (r = -0.747), aminotransferase to platelet ratio index (r = -0.604), and fibrosis 4 (r = -0.573). Median (interquartile range) LiMAx values decreased with fibrosis progression from 395 µg/kg/h (371-460 µg/kg/h) in participants with no fibrosis to 173 µg/kg/h (126-309 µg/kg/h) in patients with severe fibrosis. Median liver stiffness increased progressively with the stage of fibrosis from no fibrosis (1.56 m/s [1.52-1.63 m/s]) to moderate fibrosis (1.60 m/s [1.54-1.67 m/s]) to severe fibrosis (1.85 m/s [1.76-1.92 m/s]). CONCLUSION: Our findings show that structural changes in the liver due to progressing liver diseases and reflected by increased tissue stiffness correlate with a functional decline of the organ as reflected by a decreased metabolic capacity of the liver.

Improvement of Normothermic Ex Vivo Machine Perfusion of Rat Liver Grafts by Dialysis and Kupffer Cell Inhibition With Glycine.

Normothermic ex vivo liver machine perfusion might be a superior preservation strategy for liver grafts from extended criteria donors. However, standardized small animal models are not available for basic research on machine perfusion of liver grafts. A laboratory-scaled perfusion system was developed consisting of a custom-made perfusion chamber, a pressure-controlled roller pump, and an oxygenator. Male Wistar rat livers were perfused via the portal vein for 6 hours using oxygenated culture medium supplemented with rat erythrocytes. A separate circuit was connected via a dialysis membrane to the main circuit for plasma volume expansion. Glycine was added to the flush solution, the perfusate, and the perfusion circuit. Portal pressure and transaminase release were stable over the perfusion period. Dialysis significantly decreased the potassium concentration of the perfusate and led to significantly higher bile and total urea production. Hematoxylin-eosin staining and immunostaining for single-stranded DNA and activated caspase 3 showed less sinusoidal dilatation and tissue damage in livers treated with dialysis and glycine. Although Kupffer cells were preserved, tumor necrosis factor α messenger RNA levels were significantly decreased by both treatments. For proof of concept, the optimized perfusion protocol was tested with donation after circulatory death (DCD) grafts, resulting in significantly lower transaminase release into the perfusate and preserved liver architecture compared with baseline perfusion. In conclusion, our laboratory-scaled normothermic portovenous ex vivo liver perfusion system enables rat liver preservation for 6 hours. Both dialysis and glycine treatment were shown to be synergistic for preservation of the integrity of normal and DCD liver grafts.

Claudin-1 is linked to presence of implants and micropapillary pattern in serous borderline epithelial tumours of the ovary.

AIMS: Expression of Claudin-1 has been associated with prognosis in several cancers. Here we investigated the expression pattern of Claudin-1 in borderline tumours of the ovary (BOT). METHODS: We analysed a cohort of 114 cases of borderline tumour (BOT). Claudin-1 expression was studied by immunohistochemistry using a polyclonal antibody and was compared with clinical and histopathological characteristics. RESULTS: Strong Claudin-1 expression was found in 30 cases (26.3%) independent of histological subtype. Expression was significantly less frequent in International Federation of Gynecology and Obstetrics (FIGO) stage I (p= 0.045), while the presence of microinvasion did not correlate with Claudin-1 expression. In contrast, we detected a highly significant association of Claudin-1 expression with the presence of peritoneal implants (p=0.003) and micropapillary pattern (p=0.047), which are features exclusively seen in serous BOT. Moreover, when we restricted our analysis to the subtype of serous BOT, the association of Claudin-1 expression with peritoneal implants (p<0.001) and micropapillary pattern (p =0.003) remained highly significant. CONCLUSIONS: In conclusion, Claudin-1 expression is associated with the presence of peritoneal implants and micropapillary pattern, which have been shown to be associated with poor prognosis. We speculate that overexpression of Claudin-1 might be linked to the mitogen-activated protein kinase pathway activation in BOT and suggest further studies to define its prognostic and potential therapeutic value.

Immunohistochemical Study of Mitosis-regulatory Proteins in Gastroenteropancreatic Neuroendocrine Neoplasms.

BACKGROUND/AIM: Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are rare and heterogeneous tumors. Therapeutic targets remain to be identified and apart from the proliferation marker Ki-67, useful prognostic markers are rare. Mitotic proteins, such as forkheadbox protein M1 (FOXM1), survivin and aurora kinases, play a role in GEP-NEN progression. In this study, immunohistochemistry was used to analyze how this protein network is expressed in different subgroups of GEP-NENs and determine potential expression patterns that could be useful as tumor markers. MATERIALS AND METHODS: Tumor tissues from 75 patients were studied immunohistochemically with antibodies against aurora B, survivin and FOXM1. The expression pattern was correlated with clinicopathological data such as tumor grading, metastatic state and prognosis. RESULTS: The immunohistochemical analysis of nuclear aurora kinase B revealed a positive correlation with nuclear survivin and FOXM1 staining patterns. Furthermore, aurora B was positively related to grading and tumor size and negatively to differentiation and functionality. CONCLUSION: The expression of aurora kinase B is associated with differentiation, progression and the aggressiveness of GEP-NENs. In the context of tumor progression, aurora B is strongly associated with markers of the mitosis regulatory network, survivin, FOXM1 and Ki-67. A shift of the intracellular localization of aurora B might be useful for the subclassification of intermediate-grade intestinal NET and NEC (20%

Immunohistochemical Validation of PSMA Expression Measured by 68Ga-PSMA PET/CT in Primary Prostate Cancer.

68Ga-labeled prostate-specific membrane antigen (68Ga-PSMA) PET/CT has a proven role in staging and restaging of prostate cancer (PCA). The aims of this study were to evaluate the association of intraprostatic 68Ga-PSMA PET/CT findings and PSMA expression in immunohistochemical staining and generate a cutoff value for differentiation between normal prostate (PN) and PCA. Methods: The data of 31 patients (mean age, 67.2 y) who underwent prostatectomy and preoperative PET were retrospectively analyzed. On PET, focally increased uptake in the prostate was suggestive of tumor. A region of interest was placed on the suggestive area to generate an SUVmax; a similar region of interest was placed on adjacent visually PN. Both PCA and PN were stained with monoclonal anti-PSMA antibody (clone 3E6, 1:100, M3620). Results: All intraprostatic PCA lesions on PET could be confirmed histopathologically. In PN sections (n = 31), median staining intensity was mild, median percentage of stained cells was 20% ± 14.24%, and median immunoreactive score (IRS) was 1. In PCA sections (n = 31), median IRS was 3, median staining intensity was strong, and median percentage of stained cells was 80% ± 16.46%. The mean SUVmax (±SD) of PCA (14.06 ± 15.56) was significantly higher than that of PN (2.43 ± 0.63; P < 0.001). Receiver-operating-characteristic curve analyses of the SUVmax of PCA, validated by immunohistochemical staining in 62 tissue samples, showed the best cutoff to be 3.15 (sensitivity, 97%; specificity, 90%; area under curve, 0.987). Applied to multifocal PCA, it resulted in sensitivity and specificity of 87% and 97% respectively. The mean SUVmax of PCA and PN for an IRS of less than 2 (n = 26; 2.52 ± 0.64) was significantly lower than the mean SUVmax for an IRS of 2 or more (n = 36; 12.38 ± 15.02; P < 0.001). The mean SUVmax was significantly lower in PCA samples with fewer than 50% stained cells (n = 30; 2.81 ± 2.35) than in samples with 50% or more (n = 32; 13.34 ± 15.55; P < 0.001). There was no correlation between the SUVmax of PCA and Gleason score (P = 0.54). Conclusion: This study showed that SUVmax on 68Ga-PSMA PET/CT correlates significantly with PSMA expression in primary PCA, enabling the detection of PCA with a high sensitivity and specificity.

TFF3 Expression as Stratification Marker in Borderline Epithelial Tumors of the Ovary.

Borderline tumors (BOT) of the ovary account for 10% to 20% of ovarian neoplasms. Like ovarian cancer, BOT encompass several different histological subtypes (serous, mucinous, endometrioid, clear cell, transitional cell and mixed) with serous (SBOT) and mucinous (MBOT) the most common. Current hypotheses suggest low-grade serous carcinoma may develop in a stepwise fashion from SBOT whereas the majority of high grade serous carcinomas develop rapidly presumably from inclusion cysts or ovarian surface epithelium. The pathogenesis of mucinous ovarian tumors is still puzzling. Molecular markers could help to better define relationships between such entities. Trefoil factor-3 (TFF3) is an estrogen-regulated gene associated with prognosis in different types of cancer. It has also been included in a recent marker panel predicting subtypes of ovarian carcinoma. We analyzed the expression of TFF3 by immunohistochemistry in a cohort of 137 BOT and its association with histopathological features. Overall expression rate of TFF3 was 21.9%. None of the BOT with serous and endometrioid histology displayed strong TFF3 expression. On the other hand, TFF3 was highly expressed in 61.4% of MBOT cases and 33.3% of BOT with mixed histology (P < 0.001) suggesting a potential function of the protein in that subtypes. Associations of TFF3 expression with FIGO stage and micropapillary pattern were significant in the overall cohort but confounded by their correlation with histological subtypes. The highly specific expression of TFF3 in MBOT may help to further clarify potential relationships of tumors with mucinous histology and warrants further studies.