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Background:Biliary tract cancers (BTC) are relatively rare malignant tumours with poor prognosis. It is known from other solid neoplasms that antitumour inflammatory response has an impact on tumour behaviour and patient outcome. The aim of this study was to provide a comprehensive characterisation of antitumour inflammatory response in human BTC.Methods:Tumour-infiltrating T lymphocytes (CD4+, CD8+, and Foxp3+), natural killer cells (perforin+), B lymphocytes (CD20+), macrophages (CD68+) as well as mast cells (CD117+) were assessed by immunohistochemistry in 375 BTC including extrahepatic (ECC; n=157), intrahepatic (ICC; n=149), and gallbladder (GBAC; n=69) adenocarcinomas. Overall and intraepithelial quantity of tumour-infiltrating immune cells was analysed. Data were correlated with clinicopathological variables and patient survival.Results:The most prevalent inflammatory cell type in BTC was the T lymphocyte. Components of the adaptive immune response decreased, whereas innate immune response components increased significantly in the biliary intraepithelial neoplasia - primary carcinoma - metastasis sequence. BTC patients with intraepithelial tumour-infiltrating CD4+, CD8+, and Foxp3+ T lymphocytes showed a significantly longer overall survival. Number of total intraepithelial tumour-infiltrating Foxp3+ regulatory T lymphocytes (HR: 0.492, P=0.002) and CD4+ T lymphocytes (HR: 0.595, P=0.008) were tumour grade- and UICC-stage-independent prognosticators. The subtype-specific evaluation revealed that the tumour-infiltrating lymphocytic infiltrate is a positive outcome predictor in ECC and GBAC but not in ICC.Conclusion:Our findings characterise the immune response in cholangiocarcinogenesis and identify inflammatory cell types that influence the outcome of BTC patients. Further, we show that BTC subtypes show relevant differences with respect to density, quality of inflammation, and impact on patient survival. [ABSTRACT FROM AUTHOR]

Toll-like receptors (TLRs) expressed by mucosal epithelium play an essential role in the defense against microbes by recognizing conserved bacterial molecules. For the first time TLR4, TLR5 and TLR9 have been microanatomically localized in patients with noninflamed gastric mucosa and Helicobacter pylori gastritis by immunohistochemistry. Because polarized expression of TLRs in apical and basolateral epithelial compartments is thought to modulate mucosal immunity, subcellular TLR distribution by gastric epithelium was investigated using confocal microscopy. TLR4, TLR5 and TLR9 were expressed by gastric epithelium in antrum and corpus of all patients with H. pylori gastritis ( n = 14) and with noninflamed gastric mucosa ( n = 5). TLR4 was expressed at the apical and the basolateral pole of the gastric epithelium as well in noninflamed gastric mucosa as in H. pylori gastritis. TLR5 and TLR9 expression in the noninflamed gastric mucosa was identical to that of TLR4 with localization at the apical and the basolateral epithelial pole. However, in H. pylori gastritis TLR5 and TLR9 expression on the gastric epithelium changed to an exclusive basolateral localization without detectable expression at the apical pole. In the human stomach, the gastric epithelium expressed TLR4, TLR5 and TLR9, which gives it the possibility to interact with H. pylori. Furthermore, gastric epithelial TLR4 expression is highly polarized in an apical and a basolateral compartment, whereas TLR5 and TLR9 polarization seems to be a process dynamically influenced by H. pylori infection. This polarized and dynamically regulated gastric epithelial expression of TLRs supports a sentinel role for these receptors in the mucosal immunity to H. pylori. [ABSTRACT FROM AUTHOR]

The article describes the case of a 78-year-old woman diagnosed by double-balloon enteroscopy (DBE) with chronic anemia masking a primary large B-cell lymphoma of the small intestine. Topics discussed include the identification of a polypoid elevated mucosal lesion, observations of a lymphoma of the small bowel, and the histological analysis of the biopsies taken during DBE.

Microscopically controlled surgery (MCS) comprises various methods allowing histologically proven complete resection of malignant tumors while at the same time sparing the tumor-free tissue in the immediate vicinity as much as possible. All procedures subsumed under MCS have in common the marking of the excised tissue for topographical orientation, which provides an assignment of remaining tumor remnants. Indications for MCS are malignant skin tumors in problem localizations as well as aggressive subtypes of skin tumors. Established indications for MCS include basal cell carcinoma, cutaneous squamous cell carcinoma, Bowen's disease as well as Bowen's carcinoma, dermatofibrosarcoma protuberans, melanoma in chronically light-damaged skin as well as acral lentiginous melanoma and Merkel cell carcinoma. For other tumors such as extramammary Paget's disease and various cutaneous sarcomas, evidence exists that MCS has demonstrated benefits, such as local recurrence rates. In addition, MCS is indicated when it is foreseeable that a complex closure technique is required and complete resection of the tumor must be assured. Various methods of MCS have been described, including 3D histology, horizontal method and Mohs surgery. A close cooperation of qualified surgeons and (dermato)pathologists as well as laboratory staff is essential for the successful application of MCS., (© 2022 The Authors. Journal der Deutschen Dermatologischen Gesellschaft published by John Wiley & Sons Ltd on behalf of Deutsche Dermatologische Gesellschaft.)

Biphenotypic sinonasal sarcoma (BSNS) is a rare, low grade spindle cell sarcoma, recently recognized in the WHO classification of head and neck tumors, which is characterized by a dual myogenic and neural differentiation and recurrent gene fusions, often involving PAX3-MAML3, and less commonly PAX3 fusions with other partners such as NCOA1, NCOA2, or WWTR1. Yet, in about 4% of tumors no gene rearrangements are identified. Herein, we describe a RREB1-MKL2 fusion in a BSNS lesion occurring in a 73-year-old female patient with a right maxillo-ethmoidal angle lesion. The polypoid, moderately cellular tumor with infiltrative submucosal growth was composed of fascicles of relatively bland spindle cells embedded in a loose collagenous matrix. The tumor cells showed moderate amounts of eosinophilic cytoplasm with indistinct borders and uniform, pale, ovoid to slender nuclei. The slowly proliferating neoplastic cells co-expressed smooth muscle actin and S100, and showed focal nuclear positivity for ß-catenin, while lacking staining for cytokeratins, desmin, myogenin, caldesmon, glial fibrillary acid protein, and SOX-10. Molecular analysis by targeted RNA-based next-generation sequencing identified an in-frame fusion between exon 8 of RREB1 and exon 11 of MKL2, a genetic event that was reported to be a molecular hallmark of ectomesenchymal chondromyxoid tumor. Gene rearrangements in both genes were independently verified by fluorescence in situ hybridization (FISH). To evaluate its recurrent potential an additional group of 15 fusion negative BSNS were tested for abnormalities in RREB1 and MKL2 genes by FISH, but no additional positive cases were identified., (© 2021 The Authors. Genes, Chromosomes and Cancer published by Wiley Periodicals LLC.)

Background: Despite major advances in therapy, multiple myeloma is still an incurable malignancy in the majority of patients. To increase survival, deeper remissions (i.e. CR) translating into longer PFS need to be achieved. Incorporation of new drugs (i.e. bortezomib and lenalidomide) as induction and maintenance treatment in an intensified treatment concept, including high dose melphalan (200 mg/m 2 ), has resulted in increased CR rates, and is considered the standard of care for younger patients. Elotuzumab in combination with lenalidomide and dexamethasone has given better results as lenalidomide and dexamethasone alone in a phase III trial. The GMMG-HD6 trial will be the first phase III trial investigating the role of elotuzumab in combination with bortezomib, lenalidomide and dexamethasone (VRD) induction/consolidation and lenalidomide maintenance within a high dose concept., Methods: GMMG-HD6 is a randomized, open, multicenter phase III trial. The planned recruitment number is 564 NDMM patients. All patients will receive 4 VRD cycles as induction and undergo peripheral blood stem cell mobilization and harvesting. Thereafter they will be treated with high dose melphalan therapy plus autologous stem cell transplantation followed by 2 cycles of VRD consolidation and lenalidomide maintenance. Patients in arm B1 + B2 will additionally receive elotuzumab in the induction phase, whereas patients in A2 + B2 will be treated with elotuzumab added to consolidation and maintenance. The primary endpoint of the trial is PFS. Secondary objectives and endpoints are OS, CR rates after induction therapy comparing the two arms VRD (A1 + A2) vs VRD + elotuzumab (B1 + B2), CR rates after consolidation treatment, best response to treatment during the study, time to progression (TTP), duration of response (DOR), toxicity and quality of life., Results: Since this is the publication of a study protocol of an ongoing study, no results can be presented., Discussion: This phase III trial is designed to evaluate whether the addition of elotuzumab to an intensified treatment concept with high dose melphalan chemotherapy plus autologous stem cell transplantation and induction, consolidation and maintenance treatment with bortezomib and lenalidomide is able to improve PFS compared to the same concept without elotuzumab., Trial Registration: NCT02495922 on June 24th, 2015.

Vascularization is essential for the regeneration of bone tissue within composite material. We measured the effect of regioselectively modified cellulose/hemicellulose as an additive for porous scaffolds of collagen/hydroxyapatite nanocomposite on the tubule formation of human vascular endothelial cells. Using a coculture of endothelial cells and fibroblasts, endothelial cells formed a network of tubules within an incubation time of 14 to 24 days. A cellulose sulfate with irregular sulfation pattern along the polysaccharide backbone (13-TACS-01) led to an additional increase in vascular endothelial growth factor (VEGF)-induced tubule formation, as observed in an in vitro angiogenesis assays. In contrast with structurally different heparin, these cellulose sulfates have no apparent affinity to VEGF. Their impact on endothelial function may possibly be due to interactions with cell surface receptors/soluble factors not yet defined.

Oncogene-induced senescence (OIS) is a cellular tumor-suppressive mechanism present in several premalignant conditions. Here, we analyze the possible impact of OIS on malignant transformation in plasma cell disorders. Tumor samples from 125 patients with different disease stages were analyzed immunohistochemically for expression of senescence markers. Protein expression of cyclin-dependent kinase inhibitor p21 Cip1/Waf1 was significantly higher in smoldering multiple myeloma (SMM) compared to monoclonal gammopathy of undetermined significance (MGUS) (p = .02) or symptomatic multiple myeloma (MM) (p = .005). SMM plasma cells expressing p21 Cip1/Waf1 were negative for Ki67, consistent with senescence. While p27 Kip1 was highly expressed in healthy controls, MGUS and SMM, expression decreased significantly in MM (p = .02). SMM plasma cells displayed a mutually exclusive expression of p21 Cip1/Waf1 /p27 Kip1 suggesting compensatory mechanisms of senescence. In conclusion, we found markers of cellular senescence differentially expressed in SMM compared to MGUS and MM supporting the hypothesis of OIS as a breakpoint mechanism against malignant transformation in plasma cell disorders.

To assess the value of cardiac magnetic resonance imaging (CMR) in evaluating cardiac tumours in a tertiary cardiology centre. Between 2004 and 2014, 125 patients (pts.) from a total of 17000 who received a CMR examination in our institution were referred with the suspicion of cardiac tumours. A dedicated protocol was used that included standard cine SSFP acquisitions as well as tissue characterization using T1 and T2 black-blood (T1 BB and T2 BB respectively) with and without fat suppression, perfusion of the structure and late gadolinium enhancement. Patients' files were retrospectively analysed and data related to clinical status, results from other examinations (echocardiography), therapeutic approach and histology results, when performed, were collected. In 65 pts., a diagnosis of cardiac tumour was reached. 45 Pts had a biopsy. The CMR examination was concordant with the histology results in 35 (76%) pts. superior to that showed by echocardiography, 26 (58%) pts., p = 0.03. Forty-two (65%) pts. had a benign tumour and 23 (35%) a malignant process. Myxoma was the most frequent benign tumour, 27 (65%) and cardiac metastases were the most frequent form of malignancies, 21 (91%), with B cell non-Hodgkin lymphoma being the most frequent one, 4 (19%). Benign tumours were mostly located in the left atrium, 27 (64%) versus 6 (26%), p = 0.007, whereas malignant tumours had a predilection for the right atrium und left ventricle [11 (48%) vs. 3 (7%), p = 0.001 and 8 (35%) vs. 3 (7%), p = 0.03]. All benign cardiac tumours were single and did not show signs of infiltration. Conversely, malignant cardiac tumours were larger (43 ± 35 vs. 24 ± 16, p = 0.007) with a significant proportion (65%) showing myocardial infiltration. Pts with malignant cardiac tumours had a higher proportion of LGE (82 vs. 60%, p = 0.05) and exhibited more frequently an isointense signal in T1 BB images (78 vs. 61%, p = 0.04). Both groups showed similar proportion of perfusion and signal intensity in the T2 BB acquisitions (p = NS). CMR is a valuable tool in evaluating cardiac tumours, proving superior to echocardiography in establishing the type of cardiac tumour.

Multiple myeloma (MM) is a plasma cell malignancy that is still considered to be incurable in most cases. A dominant mutation cluster has been identified in RAS/RAF genes, emphasizing the potential significance of RAS/RAF/MEK/ERK signaling as a therapeutic target. As yet, however, the clinical relevance of this finding is unclear as clinical responses to MEK inhibition in RAS-mutant MM have been mixed. We therefore assessed RAS/RAF mutation status and MEK/ERK pathway activation by both targeted sequencing and phospho-ERK immunohistochemistry in 180 tissue biopsies from 103 patients with newly diagnosed MM (NDMM) and 77 patients with relapsed/refractory MM (rrMM). We found a significant enrichment of RAS/BRAF mutations in rrMM compared to NDMM (P=0.011), which was mainly due to an increase of NRAS mutations (P=0.010). As expected, BRAF mutations were significantly associated with activated downstream signaling. However, only KRAS and not NRAS mutations were associated with pathway activation compared to RAS/BRAF wt (P=0.030). More specifically, only KRAS G12D and BRAF V600E were consistently associated with ERK activation (P<0.001 and P=0.006, respectively). Taken together, these results suggest the need for a more specific stratification strategy consisting of both confirmation of protein-level pathway activation as well as detailed RAS/RAF mutation status to allow for a more precise and more effective application of targeted therapies, for example, with BRAF/MEK inhibitors in MM.

We performed a prospective sensitivity analysis to detect amyloid in bone marrow (BM) smears stained with Congo red (CR) and according to Pappenheim of patients with systemic light-chain (AL) amyloidosis. Results were directly compared to routine BM histology and fat aspiration. We analysed 198 BM smears from patients with the diagnosis or suspicion of systemic AL amyloidosis. Ultimately, the diagnosis could be established for 168 patients. Amyloid was detected on BM smears with CR in 33% (56/168). All patients suspicious for amyloid on Pappenheim staining (n = 39) showed substantial amyloid infiltration on CR. No patient without systemic AL amyloidosis stained positive. Sensitivity for routine BM histology was 57% (74/129) and for fat aspiration 96% (134/140). Patients with amyloid on BM smears had significantly more hepatic (42 vs. 9%, p < .001), renal (78 vs. 43%, p < .001) and gastrointestinal involvement (40 vs. 22%, p < .01) and less commonly cardiac involvement (58 vs. 76%, p < .03) and consecutively no adverse prognosis. CR staining of BM smears cannot be recommended as a primary screening tool for systemic AL as its overall sensitivity is far inferior to BM histology and fat aspiration. However, we recommend using the technique when suspecting amyloid on Pappenheim staining to establish the diagnosis of systemic AL amyloidosis.

We tested the hypothesis that proliferative activity of hematopoietic stem cells has impact on survival in newly diagnosed patients with myelodysplastic syndrome (MDS) and secondary acute myeloid leukemia (AML). RNA expression profiles of CD34(+) cells were analyzed in 125 MDS patients and compared to healthy controls. Prognostic impact on overall survival (OS) of mRNA proliferation signatures established for solid tumor cells was analyzed retrospectively. For validation on the protein level, immunofluorescence and immunohistochemistry analyses in bone marrow (BM) biopsies were performed, and an independent cohort of 223 MDS and secondary AML patients was investigated. Lower proliferative activity correlated with the expression of cyclin-dependent kinase inhibitor 1C (CDKN1C) and with shorter OS (p < 0.001). In multivariable analysis, higher CDKN1C expression was associated with worse OS (p = 0.02). On the BM level, a total of 84 (38%) patients showed CDKN1C protein expression before start of treatment. Patient, disease and treatment characteristics did not differ between CDKN1C-positive and -negative patients. Positive CDKN1C BM status was associated with shorter OS in multivariable analysis (HR 1.54, p = 0.04). There was an interaction between CDKN1C BM status and subsequent treatment with negative impact on OS being most pronounced in patients receiving conventional cytotoxic chemotherapy (n = 83, 2-year OS 30% versus 58%, p = 0.002). In conclusion, low-proliferative phenotype and CDKN1C expression were associated with shorter OS. CDKN1C protein expression in the BM of newly diagnosed, treatment-naïve MDS and secondary AML patients was identified as a prognostic factor for poor survival in patients treated with antiproliferative chemotherapy., (© 2016 UICC.)

In this study, targeted sequencing to screen 50 multidrug refractory multiple myeloma (rMM) patients was performed by using the Multiple Myeloma Mutation Panel. Patients were pretreated with both immunomodulatory drugs (IMiDs) and proteasome inhibitors (PIs), and 88%, 78%, and 68% were refractory to an IMiD, a PI, or both, respectively. The majority of patients had progressive (82%) or refractory (78%) disease immediately before sampling, with 43% being IMiD refractory and 46% being PI refractory in the most recent line of therapy. Compared with newly diagnosed MM, an increased prevalence of mutations in the Ras pathway genes KRAS, NRAS, and/or BRAF (72%), as well as TP53 (26%), CRBN (12%), and CRBN pathway genes (10%) was observed. Longitudinal analyses performed in 3 patients with CRBN mutations at time of IMiD resistance confirmed that these mutations were undetectable at earlier, IMiD-sensitive time points. Furthermore, the functional introduction of these mutations in MM cells conferred lenalidomide resistance in vitro. These data indicate a differential genetic landscape in rMM associated with drug response., (© 2016 by The American Society of Hematology.)

Systemic amyloid light chain (AL) amyloidosis is a life-threatening protein deposition disorder; however, effective therapy can dramatically improve the prognosis of AL patients. Therefore, accurate diagnosis of the underlying hematologic disease is important. Multi-parameter flow cytometry (MFC) is a reliable method to analyze lymphatic neoplasias and to detect even a small lymphatic clone. We analyzed the presence of clonal plasma cell (PC) and B cells in the bone marrow of 63 patients with newly diagnosed AL amyloidosis by MFC. We compared the results with the levels of monoclonal protein, the histopathology and cytogenetic results. As reference of light chain restriction, we used the immunohistochemical results of κ or λ positive amyloid deposits in various tissues. MFC identified underlying clonal lymphatic cells in all but two patients (61 of 63, 97%). Sixty-one patients harbored malignant PCs, whereas B-cell lymphomas were identified in two patients. Furthermore, MFC indicated at least one putative immunotherapeutical target (CD20, CD38, CD52, or SLAMF7) on malignant PCs in all but one patient. These results demonstrate that MFC is a reliable tool for an accurate diagnosis of the underlying hematologic disease and the detection of potential immunotherapeutical targets in patients with AL amyloidosis., (© 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

The activating mutation of the BRAF serine/threonine protein kinase (BRAF V600E) is the key driver mutation in hairy cell leukemia (HCL), suggesting opportunities for therapeutic targeting. We analyzed the course of 21 HCL patients treated with vemurafenib outside of trials with individual dosing regimens (240-1920 mg/d; median treatment duration, 90 days). Vemurafenib treatment improved blood counts in all patients, with platelets, neutrophils, and hemoglobin recovering within 28, 43, and 55 days (median), respectively. Complete remission was achieved in 40% (6/15 of evaluable patients) and median event-free survival was 17 months. Response rate and kinetics of response were independent of vemurafenib dosing. Retreatment with vemurafenib led to similar response patterns (n = 6). Pharmacodynamic analysis of BRAF V600E downstream targets showed that vemurafenib (480 mg/d) completely abrogated extracellular signal-regulated kinase phosphorylation of hairy cells in vivo. Typical side effects also occurred at low dosing regimens. We observed the development of acute myeloid lymphoma (AML) subtype M6 in 1 patient, and the course suggested disease acceleration triggered by vemurafenib. The phosphatidylinositol 3-kinase hotspot mutation (E545K) was identified in the AML clone, providing a potential novel mechanism for paradoxical BRAF activation. These data provide proof of dependence of HCL on active BRAF signaling. We provide evidence that antitumor and side effects are observed with 480 mg vemurafenib, suggesting that dosing regimens in BRAF-driven cancers could warrant reassessment in trials with implications for cost of cancer care., (© 2016 by The American Society of Hematology.)

The advent of individualized medicine with novel guidelines, extended quality assessment as well as intensified conventional, immunohistochemical, and molecular characterization of diseases has led to a substantial increase of pathologists' workload. Furthermore, in industrialized countries, we are facing the challenges of demographic change with an aging population. This raises the question of how pathology will be affected by these developments in the future. We extracted German population data and data on the number of board-certified physicians and pathologists from official sources. These data were reviewed in the light of data on caseload, case complexity, auxiliary diagnostic procedures, and matching patient data from a large German pathology department serving as a sector independent regional service provider. The refinement of diagnostic procedures over the last decade has resulted in a 60 % increase in slide numbers per case, doubling of immunohistochemistry procedures, and more than tripling of molecular analyses. Correlation of this development to demographics suggests that an aging population will further increase the caseload and case complexity in the coming decades since patient age is tightly linked to both parameters. This development is currently not accompanied by a sufficient increase in the number of pathologists. Our data point toward an imbalance between the increase in pathology workload and the number of pathologists. Extrapolations suggest a further aggravation of this development in the future. Thus, healthcare systems need to address this problem urgently in order to cope with these challenges.

Graft versus host disease (GvHD) is a clinically important complication after allogeneic hematopoietic stem cell transplantation (HSCT). Its diagnosis relies on clinical and histopathological findings. In order to evaluate and improve inter-institutional diagnostic agreement on histological diagnosis and grading of acute gastrointestinal GvHD, we conducted a round robin test, which included 33 biopsies from 23 patients after HSCT. Five pathologists from different institutions independently evaluated the original sections from the biopsies submitted for diagnosis. Based on their results, consensus qualitative criteria for the assessment of typical histological features of GvHD (e.g., apoptosis, crypt destruction, mucosa denudation) were proposed, including detailed descriptions as well as histological images. In a second round robin test with involvement of the same pathologists, the reproducibility of both diagnosis and grading had improved. Remaining differences were mostly related to differential diagnostic considerations, including viral infection or toxic side effects of medication, which should be resolved by integrating histopathological findings with proper clinical information.

Hairy cell leukemia (HCL) is marked by near 100% mutational frequency of BRAFV600E mutations. Recurrent cooperating genetic events that may contribute to HCL pathogenesis or affect the clinical course of HCL are currently not described. Therefore, we performed whole exome sequencing to explore the mutational landscape of purine analog refractory HCL. In addition to the disease-defining BRAFV600E mutations, we identified mutations in EZH2, ARID1A, and recurrent inactivating mutations of the cell cycle inhibitor CDKN1B (p27). Targeted deep sequencing of CDKN1B in a larger cohort of HCL patients identify deleterious CDKN1B mutations in 16% of patients with HCL (n = 13 of 81). In 11 of 13 patients the CDKN1B mutation was clonal, implying an early role of CDKN1B mutations in the pathogenesis of HCL. CDKN1B mutations were not found to impact clinical characteristics or outcome in this cohort. These data identify HCL as having the highest frequency of CDKN1B mutations among cancers and identify CDNK1B as the second most common mutated gene in HCL. Moreover, given the known function of CDNK1B, these data suggest a novel role for alterations in regulation of cell cycle and senescence in HCL with CDKN1B mutations., (© 2015 by The American Society of Hematology.)

Primary cutaneous large B-cell lymphomas, leg type (PCLBCL/LT) are primary cutaneous B-cell lymphoma (PCBCL) with an intermediate prognosis. Therefore, antracycline-based polychemotherapy combined with rituximab has been recommended as first-line treatment. Yet, despite this regimen, the 5-year survival rate remains 50-66% only. Angiogenesis, the formation of a vascular network, is essential for the pathogenesis of nodal lymphomas. So far, no study has analysed angiogenesis and its key factors in PCLBCL/LT. The present study was aimed at characterizing angiogenesis in PCLBCL/LT to identify the angiogenic molecules as potential therapeutic targets. The intra-tumoral microvessel density (MVD) was assessed by immunohistochemical studies of CD20 and CD31. The MVD was higher in PCLBCL/LT compared with indolent PCBCL. Analyses of open-source microarray data showed correlation between the angiogenic molecule angiopoietin-2 (Ang-2) and pan-endothelial cell markers. ELISA studies determined a shift between Ang-2 and Ang-1 towards Ang-2 in the peripheral blood of PCLBCL/LT patients. Immunofluorescence costainings against the Ang receptor Tie2/angiogenic integrins/CD34 revealed that the vasculature in both aggressive and indolent PCBCL tumors harbours an endothelial cell subpopulation with reduced expression of Tie2. In contrast, the alternative Ang-2 binding partners, angiogenic integrins, are strongly expressed in PCBCL. In line with these findings, downstream targets of Ang-2-integrin signalling, that is phosphorylation of focal adhesion kinase at Tyr397, and sprouting angiogenesis are enhanced in PCLBCL/LT. Our data present Ang-2 as a promising therapeutic target and anti-angiogenic therapy as a new line in treatment of PCLBCL/LT as a hitherto intractable disease., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare haematopoietic malignancy characterized by dismal prognosis and overall poor therapeutic response. Since the biology of BPDCN is barely understood, our study aims to shed light on the genetic make-up of these highly malignant tumors. Using targeted high-coverage massive parallel sequencing, we investigated 50 common cancer genes in 33 BPDCN samples. We detected point mutations in NRAS (27.3% of cases), ATM (21.2%), MET, KRAS, IDH2, KIT (9.1% each), APC and RB1 (6.1%), as well as in VHL, BRAF, MLH1, TP53 and RET1 (3% each). Moreover, NRAS-, KRAS- and ATM-mutations were found to be mutually exclusive and we observed recurrent mutations in NRAS, IDH2, APC and ATM. CDKN2A deletions were detected in 27.3% of the cases followed by deletions of RB1 (9.1%), PTEN and TP53 (3% each). The mutual exclusive distribution of some mutations may point to different subgroups of BPDCN whose biological significance remains to be explored.

Objectives: To investigate how plasma cell infiltration patterns detected by MRI match the plasma cell distribution in bone marrow biopsy., Methods: We assessed 50 patients with monoclonal plasma cell disorders of all clinical stages. MRI infiltration pattern was compared with matched BM histology from the same anatomic region., Results: MRI revealed a minimal (n=11, 22%), focal (n=5, 10%), diffuse (n=14, 28%) and mixed (n=20, 40%) infiltration pattern. Diffuse MRI pattern was predominant in smoldering myeloma patients whereas the MRI patterns with "focal component" (i.e. focal and mixed) were most common in symptomatic myeloma (p<0.01). In histology an interstitial (n=13, 26%), nodular (n=23, 46%) and packed marrow (n=14, 28%) was found respectively. All three histological types of infiltration were observed in patients with diffuse and mixed MRI patterns. Minimal MRI pattern was found in all MGUS patients and was associated with an interstitial BM infiltration. In two patients with minimal MRI pattern an extensive micro-nodular BM infiltration was found in histology., Conclusions: Infiltration patterns in MRI represent different histological growth patterns of plasma cells, but the MRI resolution is not sufficient to visualize micro-nodular aggregates of plasma cells., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Aims: Recent reports suggest a possible role for extracellular (MUC1N) and transmembrane (MUC1C) subunits of Mucin 1 (MUC1) in the pathogenesis of multiple myeloma (MM). Nuclear translocation of MUC1C is involved in activation of various oncogenic signalling pathways and both MUC1 subunits are potential therapeutic targets. We aimed at performing a comprehensive expression analysis of the MUC1 subunits in plasma cell dyscrasias., Methods and Results: Immunohistochemistry with monoclonal antibodies against the MUC1N subunit (EMA and 5E10) tumour-associated glycoforms of MUC1N (5E5) and the MUC1C subunit were applied to a series of biopsies from normal controls (n = 10) and plasma cell dyscrasias (n = 121). Clonal plasma cells showed reduced MUC1N expression, and the 5E5 MUC1N epitope was expressed only in neoplastic plasma cells. Nuclear localization of MUC1C was equally frequent in all disease stages and did not differ from the control cases. Loss of both MUC1 subunits in MM (n = 12) was associated with significantly shorter overall survival and was more frequent in pretreated MM samples., Conclusions: Our findings indicate that aberrant glycosylation of MUC1 is an early event in the pathogenesis of MM. In contrast, MUC1C nuclear localization is not likely to be a driver of tumour progression., (© 2013 John Wiley & Sons Ltd.)

Background: Aberrant DNA methylation is frequently found in human malignancies including acute myeloid leukemia (AML). While most studies focus on later disease stages, the onset of aberrant DNA methylation events and their dynamics during leukemic progression are largely unknown., Methods: We screened genome-wide for aberrant CpG island methylation in three disease stages of a murine AML model that is driven by hypomorphic expression of the hematopoietic transcription factor PU.1. DNA methylation levels of selected genes were correlated with methylation levels of CD34+ cells and lineage negative, CD127-, c-Kit+, Sca-1+ cells; common myeloid progenitors; granulocyte-macrophage progenitors; and megakaryocyte-erythroid progenitors., Results: We identified 1,184 hypermethylated array probes covering 762 associated genes in the preleukemic stage. During disease progression, the number of hypermethylated genes increased to 5,465 in the late leukemic disease stage. Using publicly available data, we found a significant enrichment of PU.1 binding sites in the preleukemic hypermethylated genes, suggesting that shortage of PU.1 makes PU.1 binding sites in the DNA accessible for aberrant methylation. Many known AML associated genes such as RUNX1 and HIC1 were found among the preleukemic hypermethylated genes. Nine novel hypermethylated genes, FZD5, FZD8, PRDM16, ROBO3, CXCL14, BCOR, ITPKA, HES6 and TAL1, the latter four being potential PU.1 targets, were confirmed to be hypermethylated in human normal karyotype AML patients, underscoring the relevance of the mouse model for human AML., Conclusions: Our study identified early aberrantly methylated genes as potential contributors to onset and progression of AML.

The glycome, i.e. the cellular repertoire of glycan structures, contributes to important functions such as adhesion and intercellular communication. Enzymes regulating cellular glycosylation processes are related to the pathogenesis of cancer including multiple myeloma. Here we analyze the transcriptional differences in the glycome of normal (n = 10) and two cohorts of 332 and 345 malignant plasma-cell samples, association with known multiple myeloma subentities as defined by presence of chromosomal aberrations, potential therapeutic targets, and its prognostic impact. We found i) malignant vs. normal plasma cells to show a characteristic glycome-signature. They can ii) be delineated by a lasso-based predictor from normal plasma cells based on this signature. iii) Cytogenetic aberrations lead to distinct glycan-gene expression patterns for t(11;14), t(4;14), hyperdiploidy, 1q21-gain and deletion of 13q14. iv) A 38-gene glycome-signature significantly delineates patients with adverse survival in two independent cohorts of 545 patients treated with high-dose melphalan and autologous stem cell transplantation. v) As single gene, expression of the phosphatidyl-inositol-glycan protein M as part of the targetable glycosyl-phosphatidyl-inositol-anchor-biosynthesis pathway is associated with adverse survival. The prognostically relevant glycome deviation in malignant cells invites novel strategies of therapy for multiple myeloma.

Modern imaging techniques have demonstrated that monoclonal plasma cell diseases infiltrate the bone marrow in a diffuse, focal, mixed pattern. While focal lesions can be easily counted and measured, the diffuse lesions of the infiltration are hard to assess. We therefore investigated 31 patients with monoclonal plasma cell diseases of all stages with intravoxel incoherent motion imaging of the same region of the pelvis from where afterwards a biopsy was obtained. We found a significant correlation between plasma cell percentage in bone marrow histology and the imaging parameters "apparent diffusion coefficient" and the diffusion coefficient D. Furthermore, those parameters correlated with other factors of disease activity, e.g., monoclonal protein, hemoglobin, and immunoparesis. In summary, we found that the non-invasively acquired imaging parameters correlated with the degree of plasma cell infiltration in the bone marrow.

Oncogene-induced senescence (OIS) is crucial for tumour suppression. Senescent cells implement a complex pro-inflammatory response termed the senescence-associated secretory phenotype (SASP). The SASP reinforces senescence, activates immune surveillance and paradoxically also has pro-tumorigenic properties. Here, we present evidence that the SASP can also induce paracrine senescence in normal cells both in culture and in human and mouse models of OIS in vivo. Coupling quantitative proteomics with small-molecule screens, we identified multiple SASP components mediating paracrine senescence, including TGF-β family ligands, VEGF, CCL2 and CCL20. Amongst them, TGF-β ligands play a major role by regulating p15(INK4b) and p21(CIP1). Expression of the SASP is controlled by inflammasome-mediated IL-1 signalling. The inflammasome and IL-1 signalling are activated in senescent cells and IL-1α expression can reproduce SASP activation, resulting in senescence. Our results demonstrate that the SASP can cause paracrine senescence and impact on tumour suppression and senescence in vivo.

In multiple myeloma, there has been little progress in the specific therapeutic targeting of oncogenic mutations. Whole-genome sequencing data have recently revealed that a subset of patients carry an activating mutation (V600E) in the BRAF kinase. To uncover the clinical relevance of this mutation in multiple myeloma, we correlated the mutation status in primary tumor samples from 379 patients with myeloma with disease outcome. We found a significantly higher incidence of extramedullary disease and a shorter overall survival in mutation carriers when compared with controls. Most importantly, we report on a patient with confirmed BRAF V600E mutation and relapsed myeloma with extensive extramedullary disease, refractory to all approved therapeutic options, who has rapidly and durably responded to low doses of the mutation-specific BRAF inhibitor vermurafenib. Collectively, we provide evidence for the development of the BRAF V600E mutation in the context of clonal evolution and describe the prognostic and therapeutic relevance of this targetable mutation.