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We discovered a novel somatic gene fusion, CD74–NRG1, by transcriptome sequencing of 25 lung adenocarcinomas of never smokers. By screening 102 lung adenocarcinomas negative for known oncogenic alterations, we found four additional fusion-positive tumors, all of which were of the invasive mucinous subtype. Mechanistically, CD74–NRG1 leads to extracellular expression of the EGF-like domain of NRG1 III-β3, thereby providing the ligand for ERBB2–ERBB3 receptor complexes. Accordingly, ERBB2 and ERBB3 expression was high in the index case, and expression of phospho-ERBB3 was specifically found in tumors bearing the fusion (P < 0.0001). Ectopic expression of CD74–NRG1 in lung cancer cell lines expressing ERBB2 and ERBB3 activated ERBB3 and the PI3K–AKT pathway, and led to increased colony formation in soft agar. Thus, CD74–NRG1 gene fusions are activating genomic alterations in invasive mucinous adenocarcinomas and may offer a therapeutic opportunity for a lung tumor subtype with, so far, no effective treatment.Significance: CD74–NRG1 fusions may represent a therapeutic opportunity for invasive mucinous lung adenocarcinomas, a tumor with no effective treatment that frequently presents with multifocal unresectable disease. Cancer Discov; 4(4); 415–22. ©2014 AACR.This article is highlighted in the In This Issue feature, p. 377

XLSX file 75K, This is an excel file containing 9 sheets, one for each of the 9 supplementary tables (S1 to S9) mentioned in the main text

PDF file 234K, This is a file containing the list of supplementary tables, the list of supplementary figures, as well as the 7 supplementary figures (S1 to S7) and their correspondent legends, mentioned in the main text

Little information is available concerning protein expression of the calcitonin receptor-like receptor (CALCRL) at the protein level. Here, we developed a rabbit monoclonal antibody, 8H9L8, which is directed against human CALCRL but cross-reacts with the rat and mouse forms of the receptor. We confirmed antibody specificity via Western blot analyses and immunocytochemistry using the CALCRL-expressing neuroendocrine tumour cell line BON-1 and a CALCRL-specific small interfering RNA (siRNA). We then used the antibody for immunohistochemical analyses of various formalin-fixed, paraffin-embedded specimens of normal and neoplastic tissues. In nearly all tissue specimens examined, CALCRL expression was detected in the capillary endothelium, smooth muscles of the arterioles and arteries, and immune cells. Analyses of normal human, rat, and mouse tissues revealed that CALCRL was primarily present in distinct cell populations in the cerebral cortex; pituitary; dorsal root ganglia; epithelia, muscles, and glands of the larger bronchi; intestinal mucosa (particularly in enteroendocrine cells); intestinal ganglia; exocrine and endocrine pancreas; arteries, capillaries, and glomerular capillary loops in the kidneys; the adrenals; Leydig cells in the testicles; and syncytiotrophoblasts in the placenta. In the neoplastic tissues, CALCRL was predominantly expressed in thyroid carcinomas, parathyroid adenomas, small-cell lung cancers, large-cell neuroendocrine carcinomas of the lung, pancreatic neuroendocrine neoplasms, renal clear-cell carcinomas, pheochromocytomas, lymphomas, and melanomas. In these tumours with strong expression of CALCRL, the receptor may represent a useful target structure for future therapies.

Little is known about the adaptor protein FAM159B. Recently, FAM159B was shown to be particularly expressed in neuroendocrine cells and tissues, such as pancreatic islets and neuroendocrine cells of the bronchopulmonary and gastrointestinal tracts, as well as in different types of neuroendocrine tumours. To gain insights into possible interactions of FAM159B with other proteins and/or receptors, we analysed the co-expression of FAM159B and various neuroendocrine-specific markers in the cancer cell lines BON-1, PC-3, NCI-h82, OH-1, and A431 and also in human pancreatic tissues and pancreatic neuroendocrine tumours. The markers included prominent markers of neuroendocrine differentiation, such as chromogranin A (CgA), neuron-specific enolase (NSE), synaptophysin (SYP), insulinoma-associated protein 1 (INSM1), neural cell adhesion molecule 1 (NCAM1), serotonin (5-HT), somatostatin-14/28 (SST), and several receptors that are typically expressed by neuroendocrine cells, such as dopamine receptor 2 (D2R), somatostatin receptor (SSTR) 1, 2, 3, 4 and 5, and regulator of G-protein signalling 9 (RGS9). FAM159B was expressed evenly throughout the cytosol in all five cancer cell lines. Immunocytochemical and immunohistochemical analyses revealed co-expression of FAM159B with SYP, INSM1, RGS9, D2R, SSTR2, SSTR3, SSTR4, and SSTR5 and strong overlapping co-localisation with NSE. Double-labelling and co-immunoprecipitation Western blot analyses confirmed a direct association between FAM159B and NSE. These results suggest the involvement of FAM159B in several intracellular signalling pathways and a direct or indirect influence on diverse membrane proteins and receptors.

Little is known about the adaptor protein FAM159B. Recently, FAM159B was shown to be particularly expressed in neuroendocrine cells and tissues, such as pancreatic islets and neuroendocrine cells of the bronchopulmonary and gastrointestinal tracts, as well as in different types of neuroendocrine tumours. To gain insights into possible interactions of FAM159B with other proteins and/or receptors, we analysed the co-expression of FAM159B and various neuroendocrine-specific markers in the cancer cell lines BON-1, PC-3, NCI-h82, OH-1, and A431 and also in human pancreatic tissues and pancreatic neuroendocrine tumours. The markers included prominent markers of neuroendocrine differentiation, such as chromogranin A (CgA), neuron-specific enolase (NSE), synaptophysin (SYP), insulinoma-associated protein 1 (INSM1), neural cell adhesion molecule 1 (NCAM1), serotonin (5-HT), somatostatin-14/28 (SST), and several receptors that are typically expressed by neuroendocrine cells, such as dopamine receptor 2 (D2R), somatostatin receptor (SSTR) 1, 2, 3, 4 and 5, and regulator of G-protein signalling 9 (RGS9). FAM159B was expressed evenly throughout the cytosol in all five cancer cell lines. Immunocytochemical and immunohistochemical analyses revealed co-expression of FAM159B with SYP, INSM1, RGS9, D2R, SSTR2, SSTR3, SSTR4, and SSTR5 and strong overlapping co-localisation with NSE. Double-labelling and co-immunoprecipitation Western blot analyses confirmed a direct association between FAM159B and NSE. These results suggest the involvement of FAM159B in several intracellular signalling pathways and a direct or indirect influence on diverse membrane proteins and receptors.

In addition to the classical oestrogen receptors, ERα and ERβ, a G protein-coupled oestrogen receptor (GPER) has been identified that primarily mediates the rapid, non-genomic signalling of oestrogens. Data on GPER expression at the protein level are contradictory; therefore, the present study was conducted to re-evaluate GPER expression by immunohistochemistry to obtain broad GPER expression profiles in human non-neoplastic and neoplastic tissues, especially those not investigated in this respect so far. We developed and thoroughly characterised a novel rabbit monoclonal anti-human GPER antibody, 20H15L21, using Western blot analyses and immunocytochemistry. The antibody was then applied to a large series of formalin-fixed, paraffin-embedded human tissue samples. In normal tissue, GPER was identified in distinct cell populations of the cortex and the anterior pituitary; islets and pancreatic ducts; fundic glands of the stomach; the epithelium of the duodenum and gallbladder; hepatocytes; proximal tubules of the kidney; the adrenal medulla; and syncytiotrophoblasts and decidua cells of the placenta. GPER was also expressed in hepatocellular, pancreatic, renal, and endometrial cancers, pancreatic neuroendocrine tumours, and pheochromocytomas. The novel antibody 20H15L21 will serve as a valuable tool for basic research and the identification of GPER-expressing tumours during histopathological examinations.

In addition to the classical oestrogen receptors, ERα and ERβ, a G protein-coupled oestrogen receptor (GPER) has been identified that primarily mediates the rapid, non-genomic signalling of oestrogens. Data on GPER expression at the protein level are contradictory; therefore, the present study was conducted to re-evaluate GPER expression by immunohistochemistry to obtain broad GPER expression profiles in human non-neoplastic and neoplastic tissues, especially those not investigated in this respect so far. We developed and thoroughly characterised a novel rabbit monoclonal anti-human GPER antibody, 20H15L21, using Western blot analyses and immunocytochemistry. The antibody was then applied to a large series of formalin-fixed, paraffin-embedded human tissue samples. In normal tissue, GPER was identified in distinct cell populations of the cortex and the anterior pituitary; islets and pancreatic ducts; fundic glands of the stomach; the epithelium of the duodenum and gallbladder; hepatocytes; proximal tubules of the kidney; the adrenal medulla; and syncytiotrophoblasts and decidua cells of the placenta. GPER was also expressed in hepatocellular, pancreatic, renal, and endometrial cancers, pancreatic neuroendocrine tumours, and pheochromocytomas. The novel antibody 20H15L21 will serve as a valuable tool for basic research and the identification of GPER-expressing tumours during histopathological examinations.

Programmed death protein 1 (PD-1) and its ligand, PD-L1, have emerged as promising therapeutic targets for many types of cancer that overexpress PD-L1. However, data on PD-L1 expression levels in bronchopulmonary neuroendocrine neoplasms (BP-NEN) are limited and contradictory. In the present study, a total of 298 archived, formalin-fixed, paraffin-embedded BP-NEN samples from 97 patients diagnosed with typical carcinoid (TC), atypical carcinoid (AC), small cell lung cancer (SCLC), or large cell neuroendocrine carcinoma of the lung (LCNEC) were evaluated for PD-L1 expression by immunohistochemistry using the highly sensitive monoclonal anti-PD-L1 antibody 73-10. PD-L1 expression levels were semiquantitatively estimated by tumour grading. Of the 298 BP-NEN samples, 85% were positive for PD-L1 expression. PD-L1 immunostaining predominantly localized to the plasma membrane of both tumour cells and tumour-infiltrating immune cells. SCLC and LCNEC exhibited significantly higher PD-L1 expression levels than TC or AC. PD-L1 expression levels were also higher in patients with lymph node or distant metastases, in patients who smoked, and in patients who died during the follow-up period. Moreover, PD-L1 expression levels correlated positively with tumour grading, Ki-67 index and the expression of the chemokine receptor CXCR4 and negatively with the levels of somatostatin receptor 1 and chromogranin A. High tumour PD-L1 levels were associated with poor patient outcomes. In conclusion, PD-L1 expression is common in BP-NEN, increases with malignancy, and is associated with poor prognosis. Therefore, targeting the PD-1/PD-L1 axis could be a promising strategy for treating BP-NEN. PD-L1 may also represent a useful prognostic biomarker for this tumour entity.

The complement component C5a and its receptor C5aR1 are involved in the development of numerous inflammatory diseases. In addition to immune cells, C5aR1 is expressed in neoplastic cells of multiple tumour entities, where C5aR1 is associated with a higher proliferation rate, advanced tumour stage, and poor patient outcomes. The aim of the present study was to obtain a broad expression profile of C5aR1 in human non-neoplastic and neoplastic tissues, especially in tumour entities not investigated in this respect so far. For this purpose, we generated a novel polyclonal rabbit antibody, {5227}, against the carboxy-terminal tail of C5aR1. The antibody was initially characterised in Western blot analyses and immunocytochemistry using transfected human embryonic kidney (HEK) 293 cells. It was then applied to a large series of formalin-fixed, paraffin-embedded non-neoplastic and neoplastic human tissue samples. C5aR1 was strongly expressed by different types of immune cells in the majority of tissue samples investigated. C5aR1 was also present in alveolar macrophages, bronchial, gut, and bile duct epithelia, Kupffer cells, occasionally in hepatocytes, proximal renal tubule cells, placental syncytiotrophoblasts, and distinct stem cell populations of bone marrow. C5aR1 was also highly expressed in the vast majority of the 32 tumour entities investigated, where a hitherto unappreciated high prevalence of the receptor was detected in thyroid carcinomas, small-cell lung cancer, gastrointestinal stromal tumours, and endometrial carcinomas. In addition to confirming published findings, we found noticeable C5aR1 expression in many tumour entities for the first time. Here, it may serve as an interesting target for future therapies.

Paragangliomas are predominantly benign tumors, but in some cases invasive growth and also metastasis are observed. Given the limited number of nonsurgical treatment options, novel target structures for diagnostics and therapy of this tumor entity are urgently needed. In the present study, expression of all five somatostatin receptor (SST) subtypes, chemokine receptor CXCR4 and endothelin receptor type A (ETA) was assessed by means of immunohistochemistry in a total of 66 paraffin-embedded paraganglioma samples from 55 patients. The stainings were rated by means of the Immunoreactive Score and correlated to clinical data and to succinate dehydrogenase subunit B (SDHB) expression. SST2A was by far the most prominent receptor in the paragangliomas investigated. It was present in 89% of the tumors at a high intensity, followed by SST5, SST3, SST1 and SST4, which were detected in 47%, 35%, 35% and 13% of the samples, respectively. SDHB positive tumors exhibited significantly higher SST2A and SST3 expression as compared to SDHB negative cases. There was no correlation between SST and Ki-67 expression or grading of the tumors and no difference in SST expression between primary tumors and metastases. Cell surface expression of CXCR4 and ETA was detected only in few samples. On tumor capillaries, however, exceptionally strong staining for these two receptors was noticed in the vast majority of the tumors. In conclusion, paragangliomas are well suited for SST2A-based diagnostics and treatment modalities. An indirect targeting of these highly vascularized tumors via CXCR4 or ETA may also represent a promising future strategy.

Pancreatic adenocarcinoma (PAC) represents one of the most fatal types of cancer with an exceptionally poor prognosis, underscoring the need for improved diagnostic and treatment approaches. An over-expression of somatostatin receptors (SST) as well as of the chemokine receptor CXCR4 has been shown for many tumour entities. Respective expression data for PAC, however, are scarce and contradictory. Overall, 137 tumour samples from 70 patients, 26 of whom were diagnosed with PAC and 44 with pancreatic neuroendocrine tumour (PanNET), were compared in terms of SST and CXCR4 expression by immunohistochemical analysis using well-characterized rabbit monoclonal antibodies. Only SST1 and CXCR4 expression was detected in PAC tumours, with SST1 present in 42.3% and CXCR4 in 7.7% of cases. However, the overall staining intensity was very weak. In contrast to the tumour cells, in many PAC cases, tumour capillaries exhibited strong SST3, SST5, or CXCR4 expression. In PanNETs, SST2 was the most-prominently expressed receptor, observed in 75.0% of the tumours at medium–strong intensity. SST5, SST1, and CXCR4 expression was detected in 20.5%, 15.9%, and 11.4% of PanNET cases, respectively, but the staining intensity was only weak. SST2 positivity in PanNET, but not in PAC, was associated with favourable patient outcomes. SST or CXCR4 expression in PAC is clearly of no therapeutic relevance. However, indirect targeting of these tumours via SST3, SST5, or CXCR4 on tumour microvessels may represent a promising additional therapeutic strategy.

Somatostatin receptors (SST), especially SST2A, are known for their overexpression in well-differentiated gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN). The chemokine receptor CXCR4, in contrast, is considered to be present mainly in highly proliferative and advanced tumors. However, comprehensive data are still lacking on potential differences in SST or CXCR4 expression pattern in GEP-NEN in dependence on the place of origin. Overall, 412 samples from 165 GEP-NEN patients, comprising both primary tumors (PT) and metastases (MTS), originating from different parts of the gastrointestinal tract or the pancreas were evaluated for SST and CXCR4 expression by means of immunohistochemistry using monoclonal antibodies. SST2A was present in 85% of PT with a high intensity of expression, followed by SST5 (23%), CXCR4 (21%), SST3 (10%), SST1 (9%), and SST4 (4%). PT displayed higher SST2A and chromogranin A (CgA) expression levels than MTS. In both PT and MTS lower SST2A and CgA expression levels were found in tumors originating from the appendix or colon, compared to tumors from other origins. Tumors derived from appendix or colon were associated with significantly worse patient outcomes. Positive correlations were noted between SST2A and CgA as well as between CXCR4 and Ki-67 expression levels. SST2A and CgA negativity of the tumors was significantly associated with poor patient outcomes. All in all, SST2A was the most prominent receptor expressed in the GEP-NEN samples investigated. However, expression levels varied considerably depending on the location of the primary tumor.

Lung cancer is highly prevalent and has an especially poor prognosis. Thus, new diagnostic and therapeutic targets are necessary. Two potential targets are somatostatin receptors (SST), which are overexpressed in well-differentiated neuroendocrine neoplasms, and the chemokine receptor CXCR4, which is present mainly in highly proliferative and advanced tumours. Although their expression is relatively well characterized in small cell lung cancer (SCLC), in non-small cell lung cancer (NSCLC), data on SST and CXCR4 expression are scarce and contradictory. We comparatively evaluated 83 tumour samples from a total of 57 lung cancer patients, of which 22 had adenocarcinoma (ADC), 21 had squamous cell carcinoma (SQC), and 15 had SCLC. Samples were evaluated for SST and CXCR4 expression using immunohistochemistry with well-characterized rabbit monoclonal antibodies. In the samples investigated, the most prominently expressed receptors were CXCR4 and SST5. Specifically, CXCR4 was detected with high expression intensity in more than 60% of ADC samples, about 90% of SQC, and 100% of SCLC. SST5 was present in about 75% of ADC and SQC samples and in more than 90% of SCLC. Although not noticeably expressed in ADC and SQC samples, SST2 was detected in 50% of SCLC cases, with a subset of patients displaying exceptionally high expression. The comparison of the three tumour entities revealed that SCLC samples had higher SST2, SST5, and CXCR4 expression, but lower SST3 and SST1 relative to ADC or SQC samples. CXCR4 may be a promising target for diagnostics and therapy in both SCLC and NSCLC.

Pulmonary large-cell neuroendocrine carcinomas (LCNECs) have similarities with other lung cancers, but their precise relationship has remained unclear. Here we perform a comprehensive genomic (n = 60) and transcriptomic (n = 69) analysis of 75 LCNECs and identify two molecular subgroups: “type I LCNECs” with bi-allelic TP53 and STK11/KEAP1 alterations (37%), and “type II LCNECs” enriched for bi-allelic inactivation of TP53 and RB1 (42%). Despite sharing genomic alterations with adenocarcinomas and squamous cell carcinomas, no transcriptional relationship was found; instead LCNECs form distinct transcriptional subgroups with closest similarity to SCLC. While type I LCNECs and SCLCs exhibit a neuroendocrine profile with ASCL1high/DLL3high/NOTCHlow, type II LCNECs bear TP53 and RB1 alterations and differ from most SCLC tumors with reduced neuroendocrine markers, a pattern of ASCL1low/DLL3low/NOTCHhigh, and an upregulation of immune-related pathways. In conclusion, LCNECs comprise two molecularly defined subgroups, and distinguishing them from SCLC may allow stratified targeted treatment of high-grade neuroendocrine lung tumors., The molecular nature of large-cell neuroendocrine lung carcinomas (LCNEC) has remained unclear. Here, the authors show LCNECs represent a distinct transcriptional subgroup among lung cancers and comprise two molecular subgroups, type I (TP53 and STK11/KEAP1 alterations) and type II (TP53 and RB1 inactivation).

Radiolabeled somatostatin (SST) analogs, used to visualize and treat SST receptor (SSTR)-expressing neuroendocrine tumors, also accumulate in the spleen. There is a high interpatient variation and no significant radiation-induced splenic toxicity; however, an absorbed dose-related reduction in spleen size was detected. However, the exact localization of radioactivity and the role of SST receptors in splenic retention are unknown. Therefore, we performed ex vivo micro-SPECT of the isolated spleen from a patient with a pancreatic neoplasm after 1 GBq (27 mCi) Lu-DOTATATE administration, followed by autoradiography and immunohistochemistry. Ex vivo autoradiography demonstrated convincingly that most radioactivity accumulated in red pulp.

// Daniel Kaemmerer 1 , Tina Trager 1, 2 , Maike Hoffmeister 3 , Bence Sipos 3 , Merten Hommann 1 , Jorg Sanger 4 , Stefan Schulz 2 , Amelie Lupp 2 1 Department of General and Visceral Surgery, Zentralklinik Bad Berka, Bad Berka, Germany 2 Department of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University, Jena, Germany 3 Institute of Pathology, University Hospital Tuebingen, Germany 4 Institute of Pathology and Cytology, Bad Berka, Germany Correspondence to: Daniel Kaemmerer, e-mail: Daniel.Kaemmerer@zentralklinik.de Keywords: somatostatin receptor, neuroendocrine tumor, neuroendocrine carcinoma, chemokine receptor, CXCR4 Received: April 13, 2015 Accepted: July 03, 2015 Published: July 14, 2015 ABSTRACT Introduction: Somatostatin receptors (SSTR) are widely distributed in well-differentiated neuroendocrine neoplasms (NEN) and serve as primary targets for diagnostics and treatment. An overexpression of the chemokine receptor CXCR4, in contrast, is considered to be present mainly in highly proliferative and advanced tumors. Comparative data are still lacking, however, for neuroendocrine carcinomas (NEC). Methods: SSTR subtype (1, 2A, 3, 5) and CXCR4 expression was evaluated in G1 ( n = 31), G2 ( n = 47), and low (G3a; Ki-67: 21–49%; n = 21) and highly proliferative (G3b; Ki-67: >50%, n = 22) G3 (total n = 43) gastroenteropancreatic NEN samples by performing immunohistochemistry with monoclonal rabbit anti-human anti-SSTR and anti-CXCR4 antibodies, respectively, and was correlated with clinical data. Results: Both CXCR4 and SSTR were widely expressed in all tumors investigated. CXCR4 expression differed significantly between the G1 and G3 specimens and within the G3 group (G3a to G3b), and was positively correlated with Ki-67 expression. SSTR2A, in contrast, exhibited an inverse association with Ki-67. SSTR2A was highly expressed in G1 and G2 tumors, but was significantly less abundant in G3 carcinomas. Additionally, SSTR1 expression was higher in G3a than in G3b tumors. Conclusion: We observed an elevation in CXCR4 and a decrease in SSTR2A expression with increasing malignancy. Interestingly, 23% of the G3 specimens had strong SSTR2A expression. Because CXCR4 was strongly expressed in highly proliferative G3 carcinomas, it is an interesting new target and needs to be validated in larger studies.

OBJECTIVE Gallium 68 somatostatin receptor (SSTR) positron emission tomography/computed tomography (PET/CT) is one of the most sensitive imaging methods for pancreatic neuroendocrine tumors. The aim of the study was to correlate the receptor density generated from the static PET/CT (maximum standard uptake values [SUVmax], mean standard uptake values [SUVmean]) with subtype 2A SSTR (SSTR2A) immunohistochemistry and reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) gene-expression data. METHODS Thirty-nine tumor specimens (17 primary pancreatic tumors [PTs], 22 metastases [MTS]) of 19 patients with PET/CT scans preoperatively were evaluated. Subtype 2A SSTR expression was quantified immunohistochemically (immunoreactive score [IRS]) and on messenger RNA (mRNA) level by RT-qPCR. RESULTS The PT and MTS did not differ significantly in their SUVmax (P = 0.07) but displayed a dissimilarity with respect to their SSTR2A expression (mean [SD] IRS PT, 8.8 [3.6] vs mean [SD] IRS MTS, 5.1 [4.5]; P = 0.02).The SUVmean was highly significantly correlated to SSTR2A mRNA expression (C = 0.85, P < 0.001) and moderately to SSTR2A protein expression (C = 0.53, P = 0.05). Moreover, the SUVmax correlated moderately with SSTR2A protein expression (C = 0.44, P = 0.03) and mRNA expression (C = 0.64, P = 0.042). CONCLUSIONS The SUVmax and SUVmean are reliable ex vivo parameters for in vivo quantification of SSTR expression in pancreatic neuroendocrine tumors. Both immunohistochemistry and RT-qPCR are comparable methods for SSTR2A quantification. The PT and MTS differ significantly in their SSTR2A expression. This fact should be taken into account when treating patients with somatostatin analogs or peptide receptor radionuclide therapy.

The endothelins ET-1, ET-2 and ET-3 are a family of peptides, which exert their actions via two G protein-coupled receptor subtypes, ETA and ETB. ET-1 is a potent vasoconstrictor and is involved in the development of different cardiovascular and renal disorders. Additionally, ET-1 and the ETA receptor have been shown to be important mediators of cancer growth and metastasis. We have extensively characterized the novel monoclonal rabbit anti-ETA antibody UMB-8 using transfected cells as well as mouse, rat and human tissues. UMB-8 was then tested in a large series of formalin-fixed and paraffin-embedded human normal and neoplastic tissue specimens. Specificity of UMB-8 was demonstrated by detection of a broad band migrating at 70-80kDa in Western blot analyses of ETA-transfected HEK-293 cells and of different mouse tissues and by agonist-dependent translocation of the immunosignal from the surface of ETA-transfected cells into the cytosol. In tissue samples, UMB-8 yielded an efficient immunostaining of distinct cell populations with a predominance of plasma membrane staining, which was abolished after preadsorption of the antibody with its immunizing peptide. In normal tissue, ETA was present in the heart, blood vessels, gut and kidneys. ETA was also detected with a hitherto unappreciated high prevalence in all types of sarcomas and in glioblastomas, but also in various epithelial tumor entities and in tumor stroma. All in all, UMB-8 may prove of great value in the identification of ETA-expressing tumors during routine histopathological examinations.

Aims Due to the growing number of somatostatin receptor (SSTR) targeting analogues and radiopeptides used for the diagnosis and therapy of neuroendocrine neoplasms (NEN), the assessment of SSTR subtype status has increasingly gained predictive value. In pathology, the SSTR protein levels are detected routinely by immunohistochemistry (IHC); however, a lack of a standardized evaluation system persists. Thus, in the present investigation, three well-established semi-quantitative scoring systems [immunoreactive score (IRS), human epidermal growth factor receptor 2 (HER2)/neu score, H score] used commonly for SSTR-IHC evaluation in NEN were compared. Methods and results A total of 240 formalin-fixed, paraffin-embedded tumour samples from 90 patients with bronchopulmonary NEN were examined by IHC and quantitative reverse transcription–polymerase chain reaction (qRT–PCR) for SSTR1, 2A, 3, 4 and 5 expression. Using both methods, SSTR1, 2A and 5 were the most frequently expressed subtypes. For all SSTR subtypes, all three scores correlated well with each other and with qRT–PCR data. However, the IRS was the most meaningful score with the best correlation to mRNA levels. Conclusions Because a unified IHC scoring system for SSTR analysis is needed urgently to optimize the theranostics of NEN, among the scores tested, the IRS seems to be the most suitable according to our results. It provides sufficient accuracy combined with high practicability.

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are heterogeneous tumors that need to be molecularly defined to obtain novel therapeutic options. Forkheadbox protein M1 (FOXM1) is a crucial transcription factor in neoplastic cells and has been associated with differentiation and proliferation. We found that FOXM1 is strongly associated with tumor differentiation and occurrence of metastases in gastrointestinal NENs. In vitro inhibition by the FOXM1 inhibitor siomycin A led to down-regulation of mitotic proteins and resulted in a strong inhibitory effect. Siomycin A decreased mitosis rate, induced apoptosis in GEP-NEN cell lines and exerts synergistic effects with chemotherapy. FOXM1 is associated with clinical outcome and FOXM1 inhibition impairs survival in vitro. We therefore propose FOXM1 as novel therapeutic target in GEP-NENs.

Gastroenteropancreatic neuroendocrine neoplasms are known for their overexpression of somatostatin receptors (SSTRs), which provide the molecular basis for diagnostic and therapeutic interventions. In contrast, few data on the SSTR expression profile exist for bronchopulmonary neuroendocrine neoplasms (BP-NEN).A total of 240 formalin-fixed, paraffin-embedded specimens from 26 typical carcinoid (TC), 30 atypical carcinoid (AC), and 34 small cell lung cancer (SCLC) patients were examined retrospectively by immunohistochemistry (IHC) using specific rabbit monoclonal antibodies and evaluated by the immunoreactive score. Adjacent slides from 20 samples of each tumor type were subjected to additional RT-quantitative PCR mRNA analysis.With different expression patterns, SSTRs were present in most of the tumor sections, at both the protein and mRNA levels. The RT-quantitative PCR data correlated with the IHC scores. SSTR1 was detected in approximately 65% of the TC and AC, but hardly in the SCLC, whereas both SSTR2A and SSTR5 were present in approximately 45% of each entity. Furthermore, the SSTR1 expression level was positively correlated with patient survival.Our results suggest that SSTRs can be used as novel diagnostic, prognostic, and therapeutic markers of BP-NEN. The differences in the SSTR expression profile between the three types of BP-NEN may help to set a diagnostic cutoff and predict patient prognosis. Similar to TC and AC, our results also revealed a previously unappreciated high level of SSTR2A expression in SCLC within a subgroup of patients. However, in most cases, pan-somatostatin analogs may represent an additional therapeutic option.

Background/Aims: The tumor suppressor p53 is rarely mutated in gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN) but they frequently show a strong expression of negative regulators of p53, rendering these tumors excellent targets for a p53 recovery therapy. Therefore, we analyzed the mechanisms of a p53 recovery therapy on intestinal neuroendocrine tumors in vitro and in vivo.Methods: By Western blot and immunohistochemistry, we found that in GEP-NEN biopsy material overexpression of MDM2 was present in intestinal NEN. Therefore, we analyzed the effect of a small-molecule inhibitor, nutlin-3a, in p53 wild-type and mutant GEP-NEN cell lines by proliferation assay, flow cytometry, immunofluorescence, Western blot, and by multiplex gene expression analysis. Finally, we analyzed the antitumor effect of nutlin-3a in a xenograft mouse model in vivo. During the study, the tumor volume was determined. Results: The midgut wild-type cell line KRJ-I responded to the treatment with cell cycle arrest and apoptosis. By gene expression analysis, we could demonstrate that nutlins reactivated an antiproliferative p53 response. KRJ-I-derived xenograft tumors showed a significantly decreased tumor growth upon treatment with nutlin-3a in vivo. Furthermore, our data suggest that MDM2 also influences the expression of the oncogene FOXM1 in a p53-independent manner. Subsequently, a combined treatment of nutlin-3a and cisplatin (as chemoresistance model) resulted in synergistically enhanced antiproliferative effects. Conclusion: In summary, MDM2 overexpression is a frequent event in p53 wild-type intestinal neuroendocrine neoplasms and therefore recovery of a p53 response might be a novel personalized treatment approach in these tumors.

Ga somatostatin receptor PET/CT, currently the most sensitive imaging modality for well-differentiated neuroendocrine tumors, is based on the molecular imaging of somatostatin receptors (SSTRs) that are expressed in different tumor entities such as neuroendocrine neoplasms, lymphomas, meningiomas, or renal cell cancer (RCC). Most neuroendocrine neoplasms show a high expression of SSTR subtypes 2A and 5, whereas the overexpression of SSTR2A in RCC is mainly seen in peritumoral vessels. Here we report a case with strongly SSTR-positive pancreatic lesions detected by Ga DOTATOC PET/CT, which histologically turned out to be ultralate metastases of a RCC.

We discovered a novel somatic gene fusion, CD74–NRG1, by transcriptome sequencing of 25 lung adenocarcinomas of never smokers. By screening 102 lung adenocarcinomas negative for known oncogenic alterations, we found four additional fusion-positive tumors, all of which were of the invasive mucinous subtype. Mechanistically, CD74–NRG1 leads to extracellular expression of the EGF-like domain of NRG1 III-β3, thereby providing the ligand for ERBB2–ERBB3 receptor complexes. Accordingly, ERBB2 and ERBB3 expression was high in the index case, and expression of phospho-ERBB3 was specifically found in tumors bearing the fusion (P < 0.0001). Ectopic expression of CD74–NRG1 in lung cancer cell lines expressing ERBB2 and ERBB3 activated ERBB3 and the PI3K–AKT pathway, and led to increased colony formation in soft agar. Thus, CD74–NRG1 gene fusions are activating genomic alterations in invasive mucinous adenocarcinomas and may offer a therapeutic opportunity for a lung tumor subtype with, so far, no effective treatment. Significance: CD74–NRG1 fusions may represent a therapeutic opportunity for invasive mucinous lung adenocarcinomas, a tumor with no effective treatment that frequently presents with multifocal unresectable disease. Cancer Discov; 4(4); 415–22. ©2014 AACR. This article is highlighted in the In This Issue feature, p. 377

// Elisa Neubauer 1 , Ralph M. Wirtz 2 , Daniel Kaemmerer 3 , Maria Athelogou 4 , Lydia Schmidt 1 , Jorg Sanger 5 , Amelie Lupp 1 1 Institute of Pharmacology and Toxicology, Jena University Hospital, Friedrich Schiller University, Jena, Germany 2 STRATIFYER Molecular Pathology GmbH Koln, Koln, Germany 3 Department of General and Visceral Surgery, Zentralklinik Bad Berka, Bad Berka, Germany 4 DEFINIENS AG, Munchen, Germany 5 Laboratory of Cytology and Pathology, Bad Berka, Germany Correspondence to: Elisa Neubauer, email: elisa.specht@med.uni-jena.de Keywords: Ki-67, topoisomerase 2 alpha, RacGAP1, lung neuroendocrine neoplasms, IHC/RT-qPCR Received: March 13, 2016 Accepted: May 16, 2016 Published: May 31, 2016 ABSTRACT The classification of bronchopulmonary neuroendocrine neoplasms (BP-NEN) into four tumor entities (typical carcinoids (TC), atypical carcinoids (AC), small cell lung cancers (SCLC), large cell neuroendocrine lung carcinomas (LCNEC)) is difficult to perform accurately, but important for prognostic statements and therapeutic management decisions. In this regard, we compared the expression of three proliferation markers, Ki-67, Topoisomerase II alpha (TOP2A), and RacGAP1, in a series of tumor samples from 104 BP-NEN patients (24 TC, 21 AC, 52 SCLC, 7 LCNEC) using different evaluation methods (immunohistochemistry (IHC): Average evaluation, Hotspot evaluation, digital image analysis; RT-qPCR). The results indicated that all three markers had increased protein and mRNA expression with poorer differentiation and correlated well with each other, as well as with grading, staging, and poor survival. Compared with Ki-67 and TOP2A, RacGAP1 allowed for a clearer prognostic statement. The cut-off limits obtained for Ki-67-Average (IHC) were TC-AC 1.5, AC-SCLC 19, and AC-LCNEC 23.5. The Hotspot evaluation generated equal to higher, the digital image analysis generally lower between-entity cut-off limits. All three markers enabled a clear-cut differentiation between the BP-NEN entities, and all methods evaluated were suitable for marker assessment. However, to define optimal cut-off limits, the Ki-67 evaluation methods should be standardized. RacGAP1 appeared to be a new marker with great potential.

Small-cell lung cancer (SCLC) is an aggressive lung tumor subtype with poor prognosis(1-3). We sequenced 29 SCLC exomes, 2 genomes and 15 transcriptomes and found an extremely high mutation rate of 7.4 +/- 1 protein-changing mutations per million base pairs. Therefore, we conducted integrated analyses of the various data sets to identify pathogenetically relevant mutated genes. In all cases, we found evidence for inactivation of TP53 and RB1 and identified recurrent mutations in the CREBBP, EP300 and MLL genes that encode histone modifiers. Furthermore, we observed mutations in PTEN, SLIT2 and EPHA7, as well as focal amplifications of the FGFR1 tyrosine kinase gene. Finally, we detected many of the alterations found in humans in SCLC tumors from Tp53 and Rb1 double knockout mice(4). Our study implicates histone modification as a major feature of SCLC, reveals potentially therapeutically tractable genomic alterations and provides a generalizable framework for the identification of biologically relevant genes in the context of high mutational background.

Somatostatin receptors (SSTR) are known for an overexpression in gastroenteropancreatic neuroendocrine tumours (GEP-NET). The aim of the present study was to find out if the receptor density predicted by the semi-quantitative parameters generated from the static positron emission tomography (PET/CT) correlated with the in vitro immunohistochemistry using a novel rabbit monoclonal anti-SSTR2A antibody (clone UMB-1) for specific SSTR2A immunohistochemistry and polyclonal antibodies for SSTR1 and 3–5. Overall 14 surgical specimens generated from 34 histologically documented GEP-NET patients were correlated with the preoperative 68Ga-DOTA-NOC PET/CT. Quantitative assessment of the receptor density was done using the immunoreactive score (IRS) of Remmele and Stegner; the additional 4-point IRS classification for immunohistochemistry and standardized uptake values (SUVmax and SUVmean) were used for PET/CT. The IRS for SSTR2A and SSTR5 correlated highly significant with the SUVmax on the PET/CT (p

// Sanaz Taromi 1 , Florentine Lewens 2 , Ruza Arsenic 5 , Dagmar Sedding 2 , Jorg Sanger 4 , Almut Kunze 4 , Markus Mobs 5 , Joana Benecke 2 , Helma Freitag 2, 11 , Friederike Christen 2, 6 , Daniel Kaemmerer 7 , Amelie Lupp 8 , Mareike Heilmann 9 , Hedwig Lammert 5 , Claus-Peter Schneider 9 , Karen Richter 9 , Michael Hummel 5 , Britta Siegmund 2 , Meike Burger 1 , Franziska Briest 2, 3, 10, * and Patricia Grabowski 2, 10, 11 * 1 Department of Medicine, Division of Hematology and Oncology, University Medical Center, Freiburg, Germany 2 Department of Gastroenterology, Infectious Diseases, Rheumatology CC13, Charite-Universitatsmedizin, Berlin, Germany 3 Department of Chemistry and Biochemistry, Freie Universitat (FU), Berlin, Germany 4 Institute of Pathology, Bad Berka, Germany 5 Institute of Pathology, Charite-Universitatsmedizin, Berlin, Germany 6 Institute of Biology, Humboldt-Universitat, Berlin, Germany 7 Department of General and Visceral Surgery, Zentralklinik Bad Berka GmbH, Bad Berka, Germany 8 Institute of Pharmacology and Toxicology, Jena University Hospital, Jena, Germany 9 Department for Oncology, Zentralklinik Bad Berka GmbH, Bad Berka, Germany 10 Department of Gastroenterology and Endocrinology, Zentralklinik Bad Berka GmbH, Bad Berka, Germany 11 Department of Medical Immunology, Charite Universitatsmedizin, Berlin, Germany * These authors have contributed equally to this work Correspondence to: Franziska Briest, email: franziska.briest@charite.de Keywords: FOXM1, in vivo , SCLC, mouse model, lung cancer Received: January 26, 2016 Accepted: August 04, 2017 Published: September 23, 2017 ABSTRACT Small cell lung cancer (SCLC) is an aggressive cancer showing a very poor prognosis because of metastasis formation at an early stage and acquisition of chemoresistance. One key driver of chemoresistance is the transcription factor Forkhead box protein M1 (FOXM1) that regulates cell cycle proliferation, maintenance of genomic stability, DNA damage response, and cell differentiation in numerous tumor entities. In this study we investigated the role of FOXM1 in SCLC progression and analyzed the effect of FOXM1 inhibition using two proteasome inhibitors, bortezomib and siomycin A. FOXM1 was strongly expressed in patient-derived SCLC samples (n=123) and its nuclear localization was associated with the proliferation marker Ki-67. Both proteasome inhibitors successfully inhibited FOXM1 expression leading to a significantly reduced proliferation and a decreased mitotic rate along with cell cycle arrest and apoptosis induction. These effects were further enhanced by addition of bortezomib to standard chemotherapy. Treatment of mice bearing chemoresistant SCLC xenografts with bortezomib reduced the mean bioluminescence signal of tumors by 54%. Similarly, treatment with cisplatin as a standard chemotherapy reduced the mean bioluminescence signal of tumors by 58%. However, in combination with standard chemotherapy bortezomib further reduced the mean bioluminescence signal by 93% (p=0.0258). In conclusion, we demonstrate the effect of bortezomib in inhibiting FOXM1 expression and thus in sensitizing resistant SCLC cells to standard chemotherapy. Thus, addition of bortezomib to standard chemotherapy might potently improve SCLC therapy, particularly in an extensive cancer stage.

We characterized genome alterations in 1255 clinically annotated lung tumors of all histological subgroups to identify genetically defined and clinically relevant subtypes. More than 55% of all cases had at least one oncogenic genome alteration potentially amenable to specific therapeutic intervention, including several personalized treatment approaches that are already in clinical evaluation. Marked differences in the pattern of genomic alterations existed between and within histological subtypes, thus challenging the original histomorphological diagnosis. Immunohistochemical studies confirmed many of these reassigned subtypes. The reassignment eliminated almost all cases of large cell carcinomas, some of which had therapeutically relevant alterations. Prospective testing of our genomics-based diagnostic algorithm in 5145 lung cancer patients enabled a genome-based diagnosis in 3863 (75%) patients, confirmed the feasibility of rational reassignments of large cell lung cancer, and led to improvement in overall survival in patients with EGFR-mutant or ALK-rearranged cancers. Thus, our findings provide support for broad implementation of genome-based diagnosis of lung cancer.

Genomic translocation events frequently underlie cancer development through generation of gene fusions with oncogenic properties. Identification of such fusion transcripts by transcriptome sequencing might help to discover new potential therapeutic targets. We developed TRUP (Tumor-specimen suited RNA-seq Unified Pipeline) (https://github.com/ruping/TRUP), a computational approach that combines split-read and read-pair analysis with de novo assembly for the identification of chimeric transcripts in cancer specimens. We apply TRUP to RNA-seq data of different tumor types, and find it to be more sensitive than alternative tools in detecting chimeric transcripts, such as secondary rearrangements in EML4-ALK-positive lung tumors, or recurrent inactivating rearrangements affecting RASSF8. Electronic supplementary material The online version of this article (doi:10.1186/s13059-014-0558-0) contains supplementary material, which is available to authorized users.

International audience; Molecularly imprinted polymers can be used as “plastic antibodies” for cell and tissue imaging, as demonstrated using hyaluronan on cell surfaces as a model target. Fluorescent nanoparticles binding a hyaluronan substructure, glucuronic acid, are used to image fixated and living cells and tissues. Plastic antibodies can be tailored to specific targets and easily labeled, and are physically and chemically stable.

Background: The tumor microenvironment plays a critical role in cancer development, progression, and control. We demonstrated in vitro and in vivo that a bidirectional crosstalk between tumor-associated macrophages and cancer cells via CCR2-CCL2 and CX3CR1-CXCL1 signaling is fundamental for lung cancer growth and metastasis offers new treatment concepts. Aim: Our working hypothesis is to develop a new platform for specific chemokine receptor (CCR2) PET imaging and a range of theranostic applications in lung cancer. For this purpose, we planned to define the CCR2 expression in NSCLC as well as in SCLC, tumor cells as well as immune/inflammatory cells. Material and Methods: This is a multicenter trial with patients from Zentralklinik Bad Berka GmbH (n =100 NSCLC, n=100 SCLC). All patients gave informed consent according to the declaration of Helsinki. FFPE material was available in all cases. CCR2 CXCR4 and CX3CR1 expression was determined by immunohistochemistry with the avidin-biotin-peroxidase-complex. Results: Analyzing 96 NSCLC (47 adenocarcinoma, 49 squamous cell carcinoma) and 45 SCLC tumor samples, we found CXCR4 and CCR2 chemokine receptor expression in tumor, immune and inflammatory cells. In NSCLC, co-expression between CCR2 and CXCR4 staining was very high concerning their expression on tumor cells rising with higher tumor stages, proliferation rate and grading. CCR2 expression in immune cells was restricted to lower stages; the same pattern could be observed in 45 SCLC tumor samples where CCR2 expression on immune cells was found especially in limited disease rather than in metastatic disease; CXCR4 expression in tumor cells was found to be high in all stages of SCLC. To evaluate the therapeutic efficacy of CCR2 antagonism in vivo, we injected LLC1 s.c. into WT mice treated with CCR2 antagonist (RS504393) or vehicle. Notably, tumor growth was significantly inhibited in CCR2 antagonist-treated mice as compared with vehicle-treated mice. Discussion: Our preliminary results show a significant portion of CCR2 positive tumors - NSCLC as well as SCLC which would qualify for a CCR2-based imaging as well as - demonstrated in our mice models - CCR2 inhibitory strategies. This should be evaluated in further preclinical trials. Citation Format: Katalin Nagy-Major, Jörg Sänger, Harshad R. Kulkarni, Peter Fix, Almut Kunze, Amelie Lupp, Reiner Bonnet, Werner Seeger, Richard P. Baum, Patricia Grabowski, Rajkumar Savai. Chemokine receptor signaling as a new tool to improve lung cancer diagnostics and therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 944. doi:10.1158/1538-7445.AM2017-944

Side-chain liquid crystalline ABA triblock copolymers with a backbone of polystyrene-block-1,2-polybutadiene-block-polystyrene and 5-[(4′-cyano-4-biphenylyl)oxy]pentanoic acid as side chains were synthesized. The block copolymers possess narrow molecular weight distributions. The liquid crystalline (LC) phase behaviour was characterized by means of differential scanning calorimetry (DSC) and X-ray scattering. Nematic and smectic polymers are accessible by variation of the spacer length.

The morphology of a liquid-crystalline ABA triblock copolymer with polystyrene (PS) blocks (12 vol %) and a side chain nematic liquid crystalline B block has been studied by TEM and temperature dependent SAXS measurements. Above the clearing temperature (T-c = 122 degrees C) the morphology is characterized by a body-centered cubic (bcc) lattice of polystyrene spheres. The transition to the nematic phase induces a reversible transition to a morphology of hexagonally packed cylinders by coalescence of the PS spheres along the [1,1,1] direction of the bcc lattice.

Statistical copolymers with mesogenic and non-mesogenic comonomer units were synthesized by partial hydroboration of the 1,2-units of polybutadiene and subsequent conversion of the alcohol groups to mesogenic units. The nature of the LC phase proves to be dependent on the mesogen content. Below a certain content the smectic C phase vanishes, and the polymer becomes cypotactic nematic. Tg, Ts,n, Tn,i and ΔHs,n depend on the mesogen content, whereas ΔHn,i is independent. No difference can be detected between the phase behaviour of homopolymers and ABA-triblock copolymers with a liquid crystalline B-block and 10 wt.-% polystyrene A-blocks.

Background Biomarkers allowing the characterization of malignancy and therapy response of oral squamous cell carcinomas (OSCC) or other types of carcinomas are still outstanding. The biochemical suicide molecule endonuclease DNaseX (DNaseI-like 1) has been used to identify the Apo10 protein epitope that marks tumor cells with abnormal apoptosis and proliferation. The transketolase-like protein 1 (TKTL1) represents the enzymatic basis for an anaerobic glucose metabolism even in the presence of oxygen (aerobic glycolysis/Warburg effect), which is concomitant with a more malignant phenotype due to invasive growth/metastasis and resistance to radical and apoptosis inducing therapies. Methods Expression of Apo10 and TKTL1 was analysed retrospectively in OSCC specimen (n = 161) by immunohistochemistry. Both markers represent independent markers for poor survival. Furthermore Apo10 and TKTL1 have been used prospectively for epitope detection in monocytes (EDIM)-blood test in patients with OSCC (n = 50), breast cancer (n = 48), prostate cancer (n = 115), and blood donors/controls (n = 74). Results Positive Apo10 and TKTL1 expression were associated with recurrence of the tumor. Multivariate analysis demonstrated Apo10 and TKTL1 expression as an independent prognostic factor for reduced tumor-specific survival. Apo10+/TKTL1+ subgroup showed the worst disease-free survival rate in OSCC. EDIM-Apo10 and EDIM-TKTL1 blood tests allowed a sensitive and specific detection of patients with OSCC, breast cancer and prostate cancer before surgery and in after care. A combined score of Apo10+/TKTL1+ led to a sensitivity of 95.8% and a specificity of 97.3% for the detection of carcinomas independent of the tumor entity. Conclusions The combined detection of two independent fundamental biophysical processes by the two biomarkers Apo10 and TKTL1 allows a sensitive and specific detection of neoplasia in a noninvasive and cost-effective way. Further prospective trials are warranted to validate this new concept for the diagnosis of neoplasia and tumor recurrence.

A titration method for quick and safe purification of solvents and monomers for anionic polymerization of styrene and dienes is presented. Protic impurities in the reaction-medium are removed by titration with butyllithium. The coloured carbanion of 4,5-methylenephenanthrene is used as an indicator to determine the end point of the titration. The titration is used in the synthesis of homopolymers and block copolymers of styrene and dienes with variable 1,2-polydiene content. Homopolymers and block copolymers in a large range of composition, molecular weight and with narrow molecular weight distribution were synthetized using the titration.

Liquid crystalline block copolymers are obtained by two consecutive polymer-analogous reactions on anionically synthesized 1,2-polybutadiene (PB) and its block copolymers with styrene. Firstly, the olefinic double bonds of the PB-blocks are converted into alcohol groups by hydroboration with BBN followed by an oxidation. Then, the mesogenic units ClCO(CH 2 ) 3 COOPhCOOPhOMe are connected to the alcohol groups. The nature of the LC phases and the transition temperatures are controlled by the microstructure of polybutadiene

Well-differentiated neuroendocrine tumors (NETs) of the lung occur as typical and atypical carcinoids. Little is known about the biology of these tumors in respect of their ability to metastasize or the probability of development of concomitant neuroendocrine tumors. Here we report a patient diagnosed with a second neuroendocrine tumor of the ileum 4 years after curative resection of a typical carcinoid of the left lung. The intestinal neuroendocrine tumor was successfully detected by gallium-68 based somatostatin receptor positron emission tomography (PET)/computed tomography (CT) and surgically removed using gamma probe detection based on the same labeling. This case report underlines the utility of somatostatin receptor PET/CT based detection and follow-up of NETs.

Somatostatin receptors (SSTR) are known for an overexpression in gastroenteropancreatic neuroendocrine tumours (GEP-NET). The aim of the present study was to find out if the receptor density predicted by the semi-quantitative parameters generated from the static positron emission tomography (PET/CT) correlated with the in vitro immunohistochemistry using a novel rabbit monoclonal anti-SSTR2A antibody (clone UMB-1) for specific SSTR2A immunohistochemistry and polyclonal antibodies for SSTR1 and 3-5.Overall 14 surgical specimens generated from 34 histologically documented GEP-NET patients were correlated with the preoperative (68)Ga-DOTA-NOC PET/CT. Quantitative assessment of the receptor density was done using the immunoreactive score (IRS) of Remmele and Stegner; the additional 4-point IRS classification for immunohistochemistry and standardized uptake values (SUV(max) and SUV(mean)) were used for PET/CT.The IRS for SSTR2A and SSTR5 correlated highly significant with the SUV(max) on the PET/CT (p0.001; p0.05) and the IRS for SSTR2A with the SUV(mean) (p0.013). The level of SSTR2A score correlated significantly with chromogranin A staining and indirectly to the tumour grading.The highly significant correlation between SSTR2A and SSTR5 and the SUV(max) on the (68)Ga-DOTA-NOC PET/CT scans is concordant with the affinity profile of (68)Ga-DOTA-NOC to the SSTR subtypes and demonstrates the excellent qualification of somatostatin analogues in the diagnostics of NET. This study correlating somatostatin receptor imaging using (68)Ga-DOTA-NOC PET/CT with immunohistochemically analysed SSTR also underlines the approval of therapy using somatostatin analogues, follow-up imaging as well as radionuclide therapy.