TP53 gene mutations occur in 70% of oesophageal adenocarcinomas (OACs). Given the central role of p53 in controlling cellular response to therapy we investigated the role of mutant (mut-) p53 and SLC7A11 in a CRISPR-mediated JH-EsoAd1 TP53 knockout model. Response to 2 Gy irradiation, cisplatin, 5-FU, 4-hydroxytamoxifen, and endoxifen was assessed, followed by a TaqMan OpenArray qPCR screening for differences in miRNA expression. Knockout of mut-p53 resulted in increased chemo- and radioresistance (2 Gy survival fraction: 38% vs. 56%, p < 0.0001) and in altered miRNA expression levels. Target mRNA pathways analyses indicated several potential mechanisms of treatment resistance. SLC7A11 knockdown restored radiosensitivity (2 Gy SF: 46% vs. 73%; p = 0.0239), possibly via enhanced sensitivity to oxidative stress. Pathway analysis of the mRNA targets of differentially expressed miRNAs indicated potential involvement in several pathways associated with apoptosis, ribosomes, and p53 signaling pathways. The data suggest that mut-p53 in JH-EsoAd1, despite being classified as non-functional, has some function related to radio- and chemoresistance. The results also highlight the important role of SLC7A11 in cancer metabolism and redox balance and the influence of p53 on these processes. Inhibition of the SLC7A11-glutathione axis may represent a promising approach to overcome resistance associated with mut-p53.

The Model for End-Stage Liver Disease (MELD)-based allocation system was implemented in Germany in 2006 in order to reduce waiting list mortality. The purpose of this study was to evaluate post-transplant results and waiting list mortality since the introduction of MELD-based allocation in our center and in Germany. Adult liver transplantation at the Charité—Universitätsmedizin Berlin was assessed retrospectively between 2005 and 2012. In addition, open access data from Eurotransplant (ET) and the German Organ Transplantation Foundation (DSO) were evaluated. In our department, 861 liver transplantations were performed from 2005 to 2012. The mean MELD score calculated with the laboratory values last transmitted to ET before organ offer (labMELD) at time of transplantation increased to 20.1 from 15.8 (Pearson’s R = 0.121, p < 0.001, confidence interval (CI) = 0.053–0.187). Simultaneously, the number of transplantations per year decreased from 139 in 2005 to 68 in 2012. In order to overcome this organ shortage the relative number of utilized liver donors in Germany has increased (85% versus 75% in non-German ET countries). Concomitantly, 5-year patient survival decreased from 79.9% in 2005 to 60.3% in 2012 (p = 0.048). At the same time, the ratio of waiting list mortality vs. active-listed patients nearly doubled in Germany (Spearman’s rho = 0.903, p < 0.001, CI = 0.634–0.977). In low-donation areas, MELD-based liver allocation may require reconsideration and inclusion of prognostic outcome factors.

BACKGROUND: Primary aldosteronism is a common but underdiagnosed cause of endocrine hypertension that contributes to global cardiovascular morbidity and mortality. It is characterized by renin-independent hyperaldosteronism that originates from adrenal lesions—the majority of which are found to harbor aldosterone-driver somatic mutations in genes encoding ion-transporting proteins. These mutations disrupt intracellular calcium homeostasis, facilitating a pathological increase in aldosterone synthase expression and aldosterone production. Elucidating the exact mechanisms causing aldosterone excess in primary aldosteronism would further the development of targeted treatments and alleviate the global hypertension burden. METHODS: Next-generation sequencing analysis of formalin-fixed paraffin-embedded aldosterone-producing adenomas identified novel somatic variants in MCOLN3 (encoding the cation-permeable channel, TRPML3). Electrophysiological, fura-2 calcium measurements, gene expression, and steroid quantification studies were performed in adrenal HAC15 cells to characterize the functional effects of the novel MCOLN3 mutations. RESULTS: Three somatic MCOLN3 variants (p.Y391D, p.F415I, and p.N411_V412delinsI) were identified in aldosterone-producing adenomas from 4 male primary aldosteronism patients. Mutated MCOLN3 expressed in HAC15 cells resulted in a gain-of-function phenotype, which induced cell membrane depolarization and calcium influx and, in turn, triggered a significant increase in aldosterone synthase expression and aldosterone production. CONCLUSIONS: This is the first report of disease-causing MCOLN3 mutations in humans and the first to implicate mutated MCOLN3 as a driver of dysregulated aldosterone production in primary aldosteronism.

Many patients with Oesophageal Adenocarcinoma (OAC) do not benefit from chemoradiotherapy treatment due to therapy resistance. To better understand the mechanisms involved in resistance and to find potential biomarkers, we investigated the association of microRNAs, which regulate gene expression, with the response to individual treatments, focusing on radiation. Intrinsic radiation resistance and chemotherapy drug resistance were assessed in eight OAC cell lines, and miRNA expression profiling was performed via TaqMan OpenArray qPCR. miRNAs discovered were either uniquely associated with resistance to radiation, cisplatin, or 5-FU, or were common to two or all three of the treatments. Target mRNA pathway analyses indicated several potential mechanisms of treatment resistance. miRNAs associated with the in vitro treatment responses were then investigated for association with pathologic response to neoadjuvant chemoradiotherapy (nCRT) in pre-treatment serums of patients with OAC. miR-451a was associated uniquely with resistance to radiation treatment in the cell lines, and with the response to nCRT in patient serums. Inhibition of miR-451a in the radiation resistant OAC cell line OE19 increased radiosensitivity (Survival Fraction 73% vs. 87%, p = 0.0003), and altered RNA expression. Pathway analysis of effected small non-coding RNAs and corresponding mRNA targets suggest potential mechanisms of radiation resistance in OAC.

Background and aims: Patients with small intestinal neuroendocrine tumors (siNETs) frequently present emergently due to bowel ischemia or bowel obstruction. The influence of emergency surgery on the prognosis of siNET remains controversial. The aim of this study was to investigate the association between type of presentation (emergency/elective) and oncological outcome. Methods: Clinicopathological data of patients who underwent bowel resection and were treated due to siNET at the Charité — Universitätsmedizin Berlin, Germany were analyzed retrospectively. Results: A total of 165 patients underwent bowel resection for siNET. Of these, 22.4% (n = 37) were emergency and 77.6% (n = 128) were elective procedures. A preoperative known diagnosis was less common in patients with emergency surgery (48.6% vs 85.2%; p < 0.001) and complete resections of all tumor manifestations were performed less often (32.4% vs 50.8%; p = 0.049), while more completion operations had to be performed (24.3% vs 11.1%; p = 0.049). Overall survival (OS) and progression-free survival (PFS) of emergently operated patients were reduced (5-year OS: 85.2% vs 89.5% ( p = 0.023); 5-year PFS: 26.7% versus 52.5% ( p = 0.018)). In addition, emergency surgery was negatively associated with OS after multivariable regression analysis. Conclusion: Emergency surgery in siNET patients is associated with adverse oncological outcomes including shorter OS and PFS. Prevention of emergency conditions should be emphasized in advanced disease.

For the histopathological work-up of resected neuroendocrine tumors of the small intestine (siNET), the determination of lymphatic (LI), microvascular (VI) and perineural (PnI) invasion is recommended. Their association with poorer prognosis has already been demonstrated in many tumor entities. However, the influence of LI, VI and PnI in siNET has not been sufficiently described yet. A retrospective analysis of all patients treated for siNET at the ENETS Center of Excellence Charité–Universitätsmedizin Berlin, from 2010 to 2020 was performed (n = 510). Patients who did not undergo primary resection or had G3 tumors were excluded. In the entire cohort (n = 161), patients with LI, VI and PnI status had more distant metastases (48.0% vs. 71.4%, p = 0.005; 47.1% vs. 84.4%, p < 0.001; 34.2% vs. 84.7%, p < 0.001) and had lower rates of curative surgery (58.0% vs. 21.0%, p < 0.001; 48.3% vs. 16.7%, p < 0.001; 68.4% vs. 14.3%, p < 0.001). Progression-free survival was significantly reduced in patients with LI, VI or PnI compared to patients without. This was also demonstrated in patients who underwent curative surgery. Lymphatic, vascular and perineural invasion were associated with disease progression and recurrence in patients with siNET, and these should therefore be included in postoperative treatment considerations.