Expression of HMB45, MelanA and SOX10 is rare in non-small cell lung cancer

Background: Non-small cell lung cancer (NSCLC) and melanoma are frequent entities in routine diagnostics. Whereas the differential diagnosis is usually straight forward based on histomorphology, it can be challenging in poorly differentiated tumors as melanoma may mimic various histological patterns. Distinction of the two entities is of outmost importance as both are treated differently. HMB45 and MelanA are recommended immunohistological markers for melanoma in this scenario. SOX10 has been described as an additional marker for melanoma. However, comprehensive large-scale data about the expression of melanoma markers in NSCLC tumor tissue specimen are lacking so far. Methods: Therefore, we analyzed the expression of these markers in 1085 NSCLC tumor tissue samples. Tissue microarrays of NSCLC cases were immunohistochemically stained for HMB45, MelanA, and SOX10. Positivity of a marker was defined as ≥1% positive tumor cells. Results: In 1027 NSCLC tumor tissue samples all melanoma as well as conventional immunohistochemical markers for NSCLC could be evaluated. HMB45, MelanA, and SOX10 were positive in 1 (< 1%), 0 (0%) and 5 (< 1%) cases. The HMB45 positive case showed co-expression of SOX10 and was classified as large cell carcinoma. Three out of five SOX10 positive cases were SqCC and one case was an adenosquamous carcinoma. Conclusions: Expression of HMB45, MelanA and SOX10 is evident but exceedingly rare in NSCLC cases. Together with conventional immunomarkers a respective marker panel allows a clear-cut differential diagnosis even in poorly differentiated tumors

Next-generation sequencing facilitates detection of the classic E13-A20 EML4-ALK fusion in an ALK-FISH/IHC inconclusive biopsy of a stage IV lung cancer patient: a case report

Background: Inhibition of the oncogenic fusion-gene EML4-ALK is a current first-line approach for patients with stage IV non-small cell lung cancer. While FISH was established as the gold standard for identifying these patients, there is accumulating evidence that other methods of detection, i.e., immunohistochemistry and next-generation sequencing (NGS), exist that may be equally successful. However, the concordance of these methods is under investigation. Case presentation: Adding to the current literature, we here report a 56 year old female never-smoker with stage IV lung adenocarcinoma whose biopsy was IHC and FISH inconclusive but positive in NGS. Retroactive profiling of the resection specimen corroborated fusion reads obtained by NGS, FISH-positivity and showed weak ALK-positivity by IHC. Consequently, we diagnosed the case as ALK-positive rendering the patient eligible to crizotinib treatment. Conclusions: With IHC on biopsy material only, this case would have been overlooked withholding effective therapy

Virotherapy combined with anti-PD-1 transiently reshapes the tumor immune environment and induces anti-tumor immunity in a preclinical PDAC model

IntroductionPancreatic ductal adenocarcinoma (PDAC) is largely refractory to cancer immunotherapy with PD-1 immune checkpoint blockade (ICB). Oncolytic virotherapy has been shown to synergize with ICB. In this work, we investigated the combination of anti-PD-1 and oncolytic measles vaccine in an immunocompetent transplantable PDAC mouse model.MethodsWe characterized tumor-infiltrating T cells by immunohistochemistry, flow cytometry and T cell receptor sequencing. Further, we performed gene expression profiling of tumor samples at baseline, after treatment, and when tumors progressed. Moreover, we analyzed systemic anti-tumor and anti-viral immunity.ResultsCombination treatment significantly prolonged survival compared to monotherapies. Tumor-infiltrating immune cells were increased after virotherapy. Gene expression profiling revealed a unique, but transient signature of immune activation after combination treatment. However, systemic anti-tumor immunity was induced by virotherapy and remained detectable even when tumors progressed. Anti-PD-1 treatment did not impact anti-viral immunity.DiscussionOur results indicate that combined virotherapy and ICB induces anti-tumor immunity and reshapes the tumor immune environment. However, further refinement of this approach may be required to develop its full potential and achieve durable efficacy

Human pluripotent stem cell-derived acinar/ductal organoids generate human pancreas upon orthotopic transplantation and allow disease modelling

Objective The generation of acinar and ductal cells from human pluripotent stem cells (PSCs) is a poorly studied process, although various diseases arise from this compartment. Design We designed a straightforward approach to direct human PSCs towards pancreatic organoids resembling acinar and ductal progeny. Results Extensive phenotyping of the organoids not only shows the appropriate marker profile but also ultrastructural, global gene expression and functional hallmarks of the human pancreas in the dish. Upon orthotopic transplantation into immunodeficient mice, these organoids form normal pancreatic ducts and acinar tissue resembling fetal human pancreas without evidence of tumour formation or transformation. Finally, we implemented this unique phenotyping tool as a model to study the pancreatic facets of cystic fibrosis (CF). For the first time, we provide evidence that in vitro, but also in our xenograft transplantation assay, pancreatic commitment occurs generally unhindered in CF. Importantly, cystic fibrosis transmembrane conductance regulator (CFTR) activation in mutated pancreatic organoids not only mirrors the CF phenotype in functional assays but also at a global expression level. We also conducted a scalable proof-of-concept screen in CF pancreatic organoids using a set of CFTR correctors and activators, and established an mRNA-mediated gene therapy approach in CF organoids. Conclusions Taken together, our platform provides novel opportunities to model pancreatic disease and development, screen for disease-rescuing agents and to test therapeutic procedures.This study was funded by the Deutsche Forschungsgemeinschaft (DFG, K.L. 2544/1-1 and 1-2), the Forschungskern SyStaR to AK, BIU (Böhringer Ingelheim Ulm to AK), the Fritz-Thyssen Foundation (Az. 10.15.2.040), the German Cancer Aid (111879) and the Else-Kröner-Fresenius-Stiftung (2011_A200). AK is indebted to the Baden-Württemberg Stiftung for the financial support of this research project by the Eliteprogramme for Postdocs. AK is also an Else-Kröner-Fresenius Memorial Fellow. LP is supported by a research fellowship of the Else-Kröner-Fresenius-Stiftung. MH was supported by the International Graduate School in Molecular Medicine and the Bausteinprogramme (L.SBN. 110), Ulm University. MM is supported by a grant of Ulm University (Baustein for Senior Clinician Scientists). IGC is funded by the Interdisciplinary Center for Clinical Research (IZKF Aachen) and Start Program, RWTH Aachen University Medical School, Aachen, German

EVI1 expression in early-stage breast cancer patients treated with neoadjuvant chemotherapy

Background Overexpression of the EVI1 (ecotropic viral integration site 1) oncogene has recently been implicated as a prognostic factor in breast cancer (BC), particularly in triple-negative BC (TNBC). In this study we aimed to investigate frequency and clinical relevance of EVI1 expression in newly diagnosed BC treated with neoadjuvant chemotherapy. Methods EVI1 expression was determined by immunohistochemistry using H-score as a cumulative measurement of protein expression in pretherapeutic biopsies of BC patients treated with anthracycline/taxane based neoadjuvant chemotherapy within the GeparTrio trial. EVI1 was analyzed as a continuous variable and dichotomized into low or high based on median expression. Endpoints were pathological complete response (pCR), disease-free survival (DFS) and overall survival (OS). Results Of the 993 tumors analyzed, 882 had available subtype information: 50.8% were HR + /HER2-, 15% HR + /HER2 + , 9.8% HR-/HER2 + , and 24.5% TNBC. Median EVI1 H-score was 112.16 (range 0.5–291.4). High EVI1 expression was significantly associated with smaller tumor size (p = 0.002) but not with BC subtype. Elevated EVI1 levels were not significantly associated with therapy response and survival in the entire cohort or within BC subtypes. However, TNBC patients with high EVI1 showed a trend towards increased pCR rates compared to low group (37.7% vs 27.5%, p = 0.114; odds ratio 1.60 (95%CI 0.90–2.85, p = 0.110) and numerically better DFS (HR = 0.77 [95%CI 0.48–1.23], log-rank p = 0.271) and OS (HR = 0.76 [95% 0.44–1.31], log-rank p = 0.314) without reaching statistical significance. Conclusion EVI1 was not associated with response to neoadjuvant therapy or patient survival in the overall cohort. Further analyses are needed to verify our findings especially in the pathological work-up of early-stage HER2-negative BC patients

Regulatory effects of SPARC on fibronectin mediated cellular responses of pancreatic ductal adenocarcinoma cells

SPARC interagiert mit zahlreichen Bestandteilen der ECM und soll einen Effekt auf Zelladhäsion, Proliferation, Migration und Invasion haben. Diese Studie untersucht die Interaktionen von SPARC mit Panc-1 in Hinblick auf Interaktionen mit Fibronektin und assoziierten Signalkaskaden. SPARC inhibiert die Proliferation von Panc-1 12% und steigert die Fibronektin-abhängige Migration um den Faktor 1,2. Molekulare Analysen konnten weder einen Effekt auf die Apoptoserate noch auf den Zellzyklus zeigen. Es wurden keine Genexpressionsänderungen als Antwort auf SPARC festgestellt. Jedoch wurden aktivierende Phosphorylierungen von FAK und Akt, sowie eine inhibierende Phosphorylierung von GSK-3$\beta$ beobachtet. Zusammengefasst zeigen die Daten eine Interaktion von SPARC und Fibronektin in Hinblick auf die Migration der Pankreaskarzinomzelllinie Panc-1 über aktivierende und inhibierende Phosphorylierungen und deren assoziierte Signalwege.SPARC interacts with various members of the ECM and is supposed to affect cell adhesion, proliferation, migration and invasion based on fibronectin interactions. This study examines interactions of SPARC with Panc-1 and fibronectin and associated signalling cascades. SPARC inhibited proliferation of Panc-1 by 12% and promoted fibronectin-dependent migration in 1.2-fold. Activating phosphorylation of FAK and Akt as well as an inhibitory phosphorylation of GSK-3$\beta$ was identified. In summary, the data presented here suggest an interaction of SPARC and fibronectin with regard to migration in the pancreatic ductal adenocarcinoma cell line Panc-1. Activating and inhibitory phosphorylations suggest potential pathways for further study. An epithelial-mesenchymal transition of Panc-1 cells due to the exposure to exogenous SPARC could not be conclusively supported. Therefore, SPARC’s molecular role in the development of pancreatic ductal adenocarcinoma requires further study

Colorectal cancer

$\textit {Background:}$ Colorec tal cancer (CRC ) is the second most common t ype of cancer in the Western world. The treatment of this disease has evolved greatly, particularly for patients with metastatic disease. The advent of combination chemotherapy plus targeted agents has led to more curative resections and improved survival rates in these patients. A deeper understanding of the mechanisms of tumorigenesis has facilitated tumor characterization, prognosis and patient stratification, bringing us one step closer towards personalized medicine. $\textit {Summary:}$ There are two main pathways of CRC development: (1) chromosomal instability, also known as the classical adenoma-carcinoma sequence, and (2) microsatellite instability, caused by a defective mismatch repair (dMMR) system. Analysis of these pathways has uncovered key prognostic and predictive biomarkers to guide patient selection and treatment strategy. This review summarizes the current treatment regimens and recent advances in the personalized therapy of CRC. $\textit {Key Message:}$ Understanding of the mechanisms of CRC pathogenesis has led to new developments in tumor characterization, patient stratification, prognosis and treatment, bringing us closer to personalized therapy. $\textit {Practical Implications:}$ In the adjuvant setting, the treatment decision is driven by clinical and histopathological factors. dMMR status is one of the most robust positive prognostic factors in resected colon cancer. More and more guidelines recommend refraining from adjuvant chemotherapy in patients with dMMR. In the metastatic setting, the introduction of effective compounds, including agents that target the epidermal growth factor receptor and vascular endothelial growth factor pathways, has significantly improved survival. The presence of wild-type KRAS and NRAS (all RAS) is a positive predictive factor for epidermal growth factor receptor antibody treatment. Therefore, analysis of all RAS status is recommended for all patients with metastatic disease prior to the initiation of first-line chemotherapy

Integrated Histogenetic Analysis Reveals BAP1-Mutated Epithelioid Mesothelioma in a Patient With Cancer of Unknown Primary

This case report presents a male patient with epithelioid mesothelioma that was initially misdiagnosed as cancer of unknown primary (CUP) and correctly identified using molecular panel sequencing. The patient had a prior history of colon and breast cancer. To assess the enlarged mediastinal lymph nodes, retrosternal lymphadenectomy was performed in 2016. The lymph nodes were histologically deemed unrelated to the known breast cancer by the reference pathologist, thus leading to the diagnosis of a CUP syndrome. When the patient presented to our center, targeted deep sequencing of both breast cancer and presumed CUP was performed to address the clonal relationship between both malignancies. A missense mutation in BAP1 was revealed in both samples, with coverage data indicating a germline event. The patient was subsequently counseled by a human geneticist and underwent genetic testing, which confirmed the germline nature of this mutation. Collectively, these data led to the diagnosis of BAP1 (BRCA1-associated protein-1) tumor predisposition syndrome (TPDS). With the knowledge of an underlying BAP1 mutation and its known frequent association with epithelioid mesothelioma, the histology was reassessed and the diagnosis was revised to epithelioid mesothelioma. At this point, peritoneal involvement of mesothelioma could be diagnosed and histologically confirmed. This case illustrates the potential of integrated histopathologic and molecular diagnostics in helping to decipher CUP syndromes and establish the correct diagnosis. Additionally, this case highlights typical features of BAP1 TPDS with its general susceptibility to cancers, with pleural and peritoneal mesotheliomas as most prevalent clinical entities and the typically more benign course of these epithelioid mesotheliomas compared with BAP1-unrelated cases of mesotheliomas