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The availability of human pancreatic islets with characteristics closely resembling those present in vivo is instrumental for ex vivo studies in diabetes research. In this review we propose metabolically phenotyped surgical patients as a novel source of pancreatic tissue for islet research. Laser Capture Microdissection from snap frozen surgical specimens is a relatively simple, reproducible and scalable method to isolate islets of highest purity for many types of "omics" analyses. Fresh pancreatic tissue slices enable the functional characterization of living islet cells in situ through dynamic experiments. Access to complete medical history and laboratory values for each donor offers the opportunity of direct correlations with different "omics" data and detailed metabolic profiling prior to pancreas surgery. Peripheral blood samples complete the picture of each patient and represent a platform for pursuit of biomarkers with uniquely comprehensive background information in regard to the donor's islet cells. Living donors provide the scientific community with a steady and abundant supply of excellent material to study islets closest to their in situ environment, thus advancing our understanding of their physiology in health and diseases. [ABSTRACT FROM AUTHOR]

Abstract: During the last decades, the evolution of treatment - including radiotherapy, chemotherapy and targeted agents - has improved the cure and survival of patients with gastrointestinal (GI) cancer. Within the past 50 years of the EORTC''s existence, significant progress has been made in the fight against cancer. During this time several cancer clinical trials were completed, and through these we are able to identify the most notable advances in GI cancer research done by the EORTC Gastrointestinal Tract Cancer Group (GI Group). Several EORTC clinical trials results have changed practice (e.g. standard of care of liver metastases of colorectal cancer has been changed by the EPOC trial) or have helped to support new treatment strategies in either early- or advanced-stage GI cancers. In addition to its clinical activities the group has started an extensive program of translational research. This changed strategy towards a translational, multidisciplinary program regarded as the basis for future developments. This review of the major achievements of the GI Group shows that it has played an important role in the scientific development of the understanding and treatment of GI cancer over the last 50 years. [Copyright &y& Elsevier]

Introduction: Pancreatic heterotopia (PH) is a common congenital anomaly and can occur anywhere in the gastrointestinal tract (GIT). In most cases, these heterotopias are asymptomatic and are only incidentally detected upon pathohistological examination or autopsy. We analyzed our cases of duodenal PH with respect to their clinical relevance and impact.Materials and Methods: Our prospectively collected pancreatic database was retrospectively analyzed. Thirty-four cases of duodenal PH were found. Specimens were reviewed by a GI pathologist. Classification was performed according to Heinrich (Type I acini, ducts, and islet cells; Type II acini and ducts; Type III only ducts).Results: From January 2000 to June 2009, we performed 534 pancreatic head resections. Thirty-two patients (6.0%) were found to have duodenal PH. Indications for pancreatic resections (pylorus-preserving pancreaticoduodenectomy, n = 26; Whipple, n = 6) were as follows: chronic pancreatitis, n = 16; malignancies, n = 9; cystic neoplasms, n = 5; and neuroendocrine neoplasms, n = 2. PH was also detected after two partial duodenal resections. In total, two cases of duodenal PH were found to be symptomatic. According to Heinrich, the following types were found: Type I, n = 12; Type II, n = 17; and Type III, n = 5 (total n = 34).Conclusions: PH is rare and in most cases detected incidentally during pathohistological examination. However, in two of our patients, surgery was performed due to symptoms. Therefore, in patients with unclear pancreatoduodenal lesions, PH should be considered as a possible diagnosis. Resection is indicated for symptomatic cases. [ABSTRACT FROM AUTHOR]

We previously have demonstrated by comparative genomic hybridization that 80% of ulcerative colitis-related cancers show loss of all or part of chromosome 18, the site of at least three candidate tumor suppressor genes: DCC, SMAD2, and SMAD4. To determine whether these genes are targeted in colitis-related carcinogenesis, we performed a high-resolution analysis of chromosome 18 alteractions in 32 colitis-related colorectal cancers by assessing allelic imbalance at 11 microsatellite markers distributed along the chromosome, and by the quantitative polymerase chain reaction (PCR) method (TaqMan). TaqMan analysis was used to determine the relative copy number of five test genes on chromosome 18 (PACAP on 18p and DCC, SMAD2, SMAD4, and GALNR on 18q). We found allelic imbalance, as assessed by loss of heterozygosity, in at least one marker on chromosome 18 in 25 of the 29 tumors (86%) successfully tested. In 14 tumors, allelic imbalance was detected at all informative markers on 18q, while the other 11 tumors showed only partial loss. Allelic imbalance was most commonly detected at D18S363 (78% of informative cases). This marker is in closest proximity to SMAD4. By quantitative PCR analysis, a relative loss of copy number of SMAD2, SMAD4, and DCC were detected in 40%, 57%, and 53%, respectively, of the colitis-related cancers. SMAD2 was retained in four tumors having loss of SMAD4 and DCC. Loss of SMAD4 alone was seen in one tumor. The present data indicate that the loss of SMAD4 and DCC occurs in the majority of colitis-related cancers. [Copyright &y& Elsevier]

Patterns of genetic alterations characterize different molecular subtypes of human gastric cancer. We aimed to establish mouse models of these subtypes. We searched databases to identify genes with unique expression in the stomach epithelium, resulting in the identification of Anxa10. We generated mice with tamoxifen-inducible Cre recombinase (CreERT2) in the Anxa10 gene locus. We created 3 mouse models with alterations in pathways that characterize the chromosomal instability (CIN) and the genomically stable (GS) subtypes of human gastric cancer: Anxa10 -CreERT2; Kras G12D/+; Tp53 R172H/+; Smad4 fl/f (CIN mice), Anxa10 -CreERT2; Cdh1 fl/fl; Kra sG12D/+; Smad4 fl/fl (GS-TGBF mice), and Anxa10 -CreERT2; Cdh1 fl/fl; Kras G12D/+; Apc fl/fl (GS-Wnt mice). We analyzed tumors that developed in these mice by histology for cell types and metastatic potential. We derived organoids from the tumors and tested their response to chemotherapeutic agents and the epithelial growth factor receptor signaling pathway inhibitor trametinib. The gastric tumors from the CIN mice had an invasive phenotype and formed liver and lung metastases. The tumor cells had a glandular morphology, similar to human intestinal-type gastric cancer. The gastric tumors from the GS–TGFB mice were poorly differentiated with diffuse morphology and signet ring cells, resembling human diffuse-type gastric cancer. Cells from these tumors were invasive, and mice developed peritoneal carcinomatosis and lung metastases. GS-Wnt mice developed adenomatous tooth-like gastric cancer. Organoids derived from tumors of GS-TGBF and GS-Wnt mice were more resistant to docetaxel, whereas organoids from the CIN tumors were more resistant to trametinib. Using a stomach-specific CreERT2 system, we created mice that develop tumors with morphologic similarities to subtypes of human gastric cancer. These tumors have different patterns of local growth, metastasis, and response to therapeutic agents. They can be used to study different subtypes of human gastric cancer. [ABSTRACT FROM AUTHOR]

Background & Aims Lymphocytic colitis is a common cause of chronic, nonbloody diarrhea. However, the effects of treatment are unclear and randomized placebo-controlled trials were requested in a Cochrane review. We performed a randomized, placebo-controlled, multicenter study to evaluate budesonide and mesalazine as induction therapy for lymphocytic colitis. Methods Patients with active lymphocytic colitis were randomly assigned to groups given budesonide 9 mg once daily (Budenofalk granules), mesalazine 3 g once daily (Salofalk granules), or placebo for 8 weeks in a double-blind, double-dummy design. The primary endpoint was clinical remission, defined as ≤21 stools (including ≤6 watery stools), in the 7 days before week 8. Results The final analysis included 57 patients (19 per group). Most patients were female (72%) and the mean age was 59 years. The proportion of patients in clinical remission at week 8 was significantly higher in the budesonide group than in the placebo group (intention-to-treat analysis, 79% vs 42%; P =.01). The difference in proportions of patients in clinical remission at week 8 between the mesalazine (63%) and placebo groups was not significant (P =.09). The proportion of patients with histologic remission at week 8 was significantly higher in the budesonide group (68%) vs the mesalazine (26%; P =.02) or placebo (21%; P =.008) groups. The incidence of adverse events was 47.4% in the budesonide group, 68.4% in the mesalazine group, and 42.1% in the placebo group. Conclusions In a randomized multicenter study, we found oral budesonide 9 mg once daily to be effective and safe for induction of clinical and histologic remission in patients with lymphocytic colitis, compared with placebo. Oral mesalazine 3 g once daily was not significantly better than placebo. ClinicalTrials.gov no: NCT01209208. [ABSTRACT FROM AUTHOR]

Numerous factors determine the current poor prognosis of pancreatic ductal adenocarcinoma (PDAC). One of the greatest challenges to overcome is treatment resistance. Among a large repertoire of intrinsic resistance mechanisms, integrin-mediated cell adhesion to extracellular matrix (ECM) has been identified to be fundamental. Coalesced in focal adhesion complexes, integrins, receptor tyrosine kinases, protein kinases and adapter proteins mediate prosurvival signaling. Four and a half LIM domains protein 2 (FHL2) is one of these adapter proteins, which operates through protein–protein interactions and shows tumor-specific expression. Based on this, we investigated FHL2 expression in PDAC specimens and three-dimensionally grown cell lines and how FHL2 mechanistically contributes to cell survival, cell cycling and radiation resistance. PDAC exhibited a significantly increased and heterogeneous FHL2 expression. Upon FHL2 depletion, pancreatic cancer cell lines showed significantly decreased cell survival, proliferation and radioresistance as well as enhanced apoptosis and MEK/ERK signaling and cyclin D1, E, A and B1 expression were strongly induced. Targeting of FHL2 and MEK1 was similarly effective than FHL2 depletion alone, suggesting MEK1 as a downstream signaling mediator of FHL2. Taken together, our results provide evidence for the importance of the focal adhesion protein FHL2 in pancreatic cancer cell survival, proliferation and radiosensitivity. [ABSTRACT FROM AUTHOR]

Abstract: Metabolic imaging and early response assessment by positron emission tomography (PET) are gaining importance in guiding treatment of localised and metastatic gastrointestinal tumours. During a workshop organised by the European Organisation of Research and Treatment of Cancer (EORTC) Gastrointestinal Tract Cancer Group the most relevant research questions, methodological aspects and unmet clinical needs in this disease were discussed. Potential future trials were drafted. This paper reviews the lectures and discussions held during this workshop and summarises the action points for the further investigation of metabolic imaging to guide treatment in gastrointestinal tumours. [Copyright &y& Elsevier]

• Duodenal biopsies are the most sensitive in diagnosing aGVHD of the upper GIT. • Duodenal biopsies reveal upper GIT aGVHD severity best. • Histological and clinical grades of aGVHD of the upper GIT correlate tightly. • Clinical grading of aGVHD predicts NRM better than histological grading. Acute graft-versus-host-disease (aGVHD) is the main cause of morbidity and nonrelapse mortality (NRM) following allogeneic hematopoietic cell transplantation (alloHCT). Nausea, vomiting, and anorexia after alloHCT can be early signs of aGVHD of the gastrointestinal tract (GIT) but may also reflect lasting mucosal damage or side effects of drugs. If upper GIT aGVHD is suspected, upper endoscopic evaluation and histological examination are crucial. Still, the interpretation of clinical symptoms, macroscopical alterations, and histological findings can be challenging. Therefore, we conducted a retrospective analysis on single-center data from 174 patients with suspected aGVHD of the upper GIT who underwent upper endoscopy within the first 6 weeks after alloHCT, to study the distribution of aGVHD-related histological findings in relation to clinical symptoms and macroscopic findings and to correlate the severity of changes with data on relapse and NRM. Our data suggest that biopsies of the duodenum reveal the severity of upper GIT aGVHD most accurately. While the histological grading correlated weakly with the severity of macroscopic changes, we found a tight correlation between histological and clinical grades of upper GIT aGVHD (p < 0.001). Although correlation of histological grading of upper GIT aGVHD with the risk for NRM missed statistical significance (HR 1.53, Lerner ≥1° versus <1º, p = 0.13), overall clinical aGVHD severity correlated with NRM (HR 4.3, IIIº–IVº versus 0–Iº, p < 0.01). In conclusion, biopsies from the duodenum are most sensitive in excluding aGVHD in patients with normal macroscopic findings at esophagogastroduodenoscopy. Clinical grading of aGVHD predicts NRM better than histological grading. [ABSTRACT FROM AUTHOR]

Multimodal primary treatment of localised adenocarcinoma of the stomach, the oesophagus and the oesophagogastric junction (AEG) was reviewed by a multidisciplinary expert panel in a moderated consensus session. Here, we report the key points of the discussion and the resulting recommendations. The exact definition of the tumour location and extent by white light endoscopy in conjunction with computed tomography scans is the backbone for any treatment decision. Their value is limited with respect to the infiltration depth, lymph node involvement and peritoneal involvement. Additional endoscopic ultrasound was recommended mainly for tumours of the lower oesophagogastric junction (i.e. AEG type II and III according to Siewert) and in early cancers before endoscopic resection. Laparoscopy to diagnose peritoneal involvement was thought to be necessary before the start of neoadjuvant treatment in all gastric cancers and in AEG type II and III. In general, perioperative multimodal treatment was suggested for all locally advanced oesophageal tumours and for gastric cancers with a clinical stage above T1N0. There was consensus that the combination of fluorouracil, folinic acid, oxaliplatin and docetaxel is now a new standard chemotherapy (CTx) regimen for fit patients. In contrast, the optimal choice of perioperative CTx versus neoadjuvant radiochemotherapy (neoRCTx), especially for AEG, was identified as an open question. Expert treatment recommendations depend on the tumour location, biology, the risk of incomplete (R1) resection, response to treatment, local or systemic recurrence risks, the predicted perioperative morbidity and patients' comorbidities. In summary, any treatment decision requires an interdisciplinary discussion in a comprehensive multidisciplinary setting. • Summary report of the expert consensus discussion and vote focussed on the primary treatment of gastric and gastro-oesophageal adenocarcinoma. • Expert consensus. • EUS needed in AEG II/III. • Laparoscopy in all gastric cancers and AEG II/III. • FLOT regimen standard in gastric cancer. [ABSTRACT FROM AUTHOR]

The primary treatment of pancreatic cancer was the topic of the 3rd St. Gallen Conference 2016. A multidisciplinary panel reviewed the current evidence and discussed controversial issues in a moderated consensus session. Here we report on the key expert recommendations. It was generally accepted that radical surgical resection followed by adjuvant chemotherapy offers the only evidence-based treatment with a chance for cure. Initial staging should classify localised tumours as resectable or unresectable (i.e. locally advanced pancreatic cancer) although there remains a large grey-zone of potentially resectable disease between these two categories which has recently been named as borderline resectable, a concept which was generally accepted by the panel members. However, the definition of these borderline-resectable (BR) tumours varies between classifications due to their focus on either (i) technical hurdles (e.g. the feasibility of vascular resection) or (ii) oncological outcome (e.g. predicting the risk of a R1 resection and/or occult metastases). The resulting expert discussion focussed on imaging standards as well as the value of pretherapeutic laparoscopy. Indications for biliary drainage were seen especially before neoadjuvant therapy. Following standard resection, the panel unanimously voted for the use of adjuvant chemotherapy after R0 resection and considered it as a reasonable standard of care after R1 resection, even though the optimal pathologic evaluation and the definition of R0/R1 was the issue of an ongoing debate. The general concept of BR tumours was considered as a good basis to select patients for preoperative therapy, albeit its current impact on the therapeutic strategy was far less clear. Main focus of the conference was to discuss the limits of surgical resection and to identify ways to standardise procedures and to improve curative outcome, including adjuvant and perioperative treatment. [ABSTRACT FROM AUTHOR]

Primary treatment of rectal cancer was the focus of the second St. Gallen European Organisation for Research and Treatment of Cancer (EORTC) Gastrointestinal Cancer Conference. In the context of the conference, a multidisciplinary international expert panel discussed and voted on controversial issues which could not be easily answered using published evidence. Main topics included optimal pretherapeutic imaging, indication and type of neoadjuvant treatment, and the treatment strategies in advanced tumours. Here we report the key recommendations and summarise the related evidence. The treatment strategy for localised rectal cancer varies from local excision in early tumours to neoadjuvant radiochemotherapy (RCT) in combination with extended surgery in locally advanced disease. Optimal pretherapeutic staging is a key to any treatment decision. The panel recommended magnetic resonance imaging (MRI) or MRI + endoscopic ultrasonography (EUS) as mandatory staging modalities, except for early T1 cancers with an option for local excision, where EUS in addition to MRI was considered to be most important because of its superior near-field resolution. Primary surgery with total mesorectal excision was recommended by most panellists for some early tumours with limited risk of recurrence (i.e. cT1-2 or cT3a N0 with clear mesorectal fascia on MRI and clearly above the levator muscles), whereas all other stages were considered for multimodal treatment. The consensus panel recommended long-course RCT over short-course radiotherapy for most clinical situations where neoadjuvant treatment is indicated, with the exception of T3a/b N0 tumours where short-course radiotherapy or even no neoadjuvant therapy were regarded to be an option. In patients with potentially resectable tumours and synchronous liver metastases, most panel members did not see an indication to start with classical fluoropyrimidine-based RCT but rather favoured preoperative short-course radiotherapy with systemic combination chemotherapy or alternatively a liver-first resection approach in resectable metastases, which both allow optimal systemic therapy for the metastatic disease. In general, proper patient selection and discussion in an experienced multidisciplinary team was considered as crucial component of care. [ABSTRACT FROM AUTHOR]

The new therapeutic approach of using immune checkpoint inhibitors as anticancer agents is a landmark innovation. Early studies suggest that immune checkpoint inhibition might also be effective in patients with gastrointestinal cancer. To improve the efficacy of immunotherapy, different strategies are currently under evaluation. This review summarises the discussion during the European Organisation for Research and Treatment of Cancer Gastrointestinal Tract Cancer Translational Research Meeting in Mainz in November 2014 and provides an update on the most recent results of immune therapy in gastrointestinal cancers. Knowledge of potential relationships between tumour cells and their microenvironment including the immune system will be essential in gastrointestinal malignancies. In this context, the density of T cell infiltration within colorectal cancer metastases has been associated with response to chemotherapy, and a high expression of programmed cell death ligand 1 (PD-L1) in advanced gastric cancer has been related with poor prognosis. Effective targets might include neo-antigens encoded from genes carrying tumour-specific somatic mutations. Tailored immunotherapy based on such mutations could enable the effective targeting of an individual patient’s tumour with vaccines produced on demand. Other strategies considering checkpoint inhibitors have shown efficacy by targeting cytotoxic T-lymphocyte-associated protein 4 and PD-1 or PD-L1. DNA mismatch repair-deficient tumours appear to be potentially the best candidates for these therapies. Finally, the combination of oncolytic viruses with immunotherapy might boost antitumour activity as well. Further evaluation of these promising immunological therapeutic approaches will require large prospective clinical studies. [ABSTRACT FROM AUTHOR]

Aim To investigate whether the immune response in colorectal liver metastases is related to progression free survival (PFS) and if this may be influenced by systemic therapy. Methods A retrospective central collection of tumour tissue was organised for the European Organisation for Research and Treatment of Cancer (EORTC) study 40983, where patients with colorectal liver metastases were treated by either resection alone or resection with perioperative FOLFOX. Immunostaining on whole slides was performed to recognise T-lymphocytes (CD3+, CD4+, CD8+), B-lymphocytes (CD20+), macrophages (CD68+) and mast cells (CD117+) inside the tumour, at the tumour border (TNI) and in normal liver tissue surrounding the tumour (0.5–2 mm from the TNI). Immunological response was compared between treatment arms and correlated to PFS. Results Tumour tissue and immune response profiles were available for 82 resected patients, 38 in the perioperative chemotherapy arm and 44 in the surgery alone arm. Baseline patient and disease characteristics were similar between the treatment arms. In response to chemotherapy, we observed increased CD3+ lymphocyte and mast cell counts inside the tumour ( p < 0.01), lower CD4+ lymphocytes in the normal liver tissue ( p = 0.02) and lower macrophage counts in normal tissue ( p < 0.01) and at the TNI ( p = 0.02). High number of CD3+ lymphocyte and mast cells, and high T-cell score were correlated with tumour regression grade (TRG). Prolonged PFS correlated with the presence of mast cells in the tumour (9.8 versus 16.5 months, Hazard ratio (HR) 0.54 p = 0.03), higher CD3+ lymphocyte count at the TNI (10.8 versus 22.8 months, HR 0.57, p = 0.03) and T-cell score >2 (10.8 versus 38.6 months, HR 0.51, p = 0.04). Conclusion Our analyses in the context of a randomised study suggest that chemotherapy influences immune cell profiles, independent of patient characteristics. Immune responses of lymphocytes and mast cells were associated with pathological response to chemotherapy and to increased PFS. High CD3+ lymphocytes at the tumour front and intratumoural mast cells appear to be prognostic for patients with colorectal liver metastases. [ABSTRACT FROM AUTHOR]

Background Using potential surrogate end-points for overall survival (OS) such as Disease-Free- (DFS) or Progression-Free Survival (PFS) is increasingly common in randomised controlled trials (RCTs). However, end-points are too often imprecisely defined which largely contributes to a lack of homogeneity across trials, hampering comparison between them. The aim of the DATECAN (Definition for the Assessment of Time-to-event End-points in CANcer trials)-Pancreas project is to provide guidelines for standardised definition of time-to-event end-points in RCTs for pancreatic cancer. Methods Time-to-event end-points currently used were identified from a literature review of pancreatic RCT trials (2006–2009). Academic research groups were contacted for participation in order to select clinicians and methodologists to participate in the pilot and scoring groups (>30 experts). A consensus was built after 2 rounds of the modified Delphi formal consensus approach with the Rand scoring methodology (range: 1–9). Results For pancreatic cancer, 14 time to event end-points and 25 distinct event types applied to two settings (detectable disease and/or no detectable disease) were considered relevant and included in the questionnaire sent to 52 selected experts. Thirty experts answered both scoring rounds. A total of 204 events distributed over the 14 end-points were scored. After the first round, consensus was reached for 25 items; after the second consensus was reached for 156 items; and after the face-to-face meeting for 203 items. Conclusion The formal consensus approach reached the elaboration of guidelines for standardised definitions of time-to-event end-points allowing cross-comparison of RCTs in pancreatic cancer. [ABSTRACT FROM AUTHOR]

Abstract: Aim of the study: Small bowel adenocarcinoma (SBA) is a rare and aggressive tumour with poor outcomes. Because of its low incidence, the number prospective studies remains insufficient leading to poor knowledge and absence of standard of care. Aiming to better understand small bowel carcinogenesis we investigated the frequency of somatic mutations in a large data set of patients in more than 740 mutational hotspots among 46 genes. Methods: In total, 83 SBA cases were selected from two European databases. The sequencing was performed using the Ion 316 Chip. Additionally we looked into ERBB2 expression and microsatellite instability (MSI) status. Results: The tumours most frequently were duodenal (47%) and stage ⩾3 (63%). Eight genes were mutated with a frequency >5%: KRAS, TP53, APC, SMAD4, PIK3CA, ERBB2, BRAF and FBXW7. ERBB2 alterations are present in 10 patients (12%) through mutations (7 cases) or amplifications (3 cases). ERBB2 mutations were significantly associated with duodenal tumour location (P =0.04). In this group, there was a positive association with dMMR status (P =0.006) and APC mutation (P =0.02) but negative association with p53 mutations (P =0.038). Conclusions: This study describes the first large screening of somatic mutations in SBA using next generation sequencing. The ERBB2 mutation was revealed to be one of the most frequent alterations in SBA with a distribution dependent on tumour location. In most cases ERBB2 mutation was identical (p.L755S). In clinical practice, this may suggest that more than 10% of the patients with SBA could be treated using an anti-ERBB2-targeted agent. [Copyright &y& Elsevier]

Pancreatic cancer is characterized by a high degree of resistance to chemotherapy. Epidermal growth factor receptor (EGFR) inhibition using the small-molecule inhibitor erlotinib was shown to provide a small survival benefit in a subgroup of patients. To identify kinases whose inhibition acts synergistically with erlotinib, we employed a kinome-wide small-interfering RNA (siRNA)-based loss-of-function screen in the presence of erlotinib. Of 779 tested kinases, we identified several targets whose inhibition acted synergistically lethal with EGFR inhibition by erlotinib, among them the S6 kinase ribosomal protein S6 kinase 2 (RPS6KA2)/ribosomal S6 kinase 3. Activated RPS6KA2 was expressed in approximately 40% of 123 human pancreatic cancer tissues. RPS6KA2 was shown to act downstream of EGFR/RAS/mitogen-activated protein kinase kinase (MEK)/extracellular-signal regulated kinase (ERK) signaling and was activated by EGF independently of the presence of KRAS mutations. Knockdown of RPS6KA2 by siRNA led to increased apoptosis only in the presence of erlotinib, whereas RPS6KA2 activation or overexpression rescued from erlotinib- and gemcitabine-induced apoptosis. This effect was at least in part mediated by downstream activation of ribosomal protein S6. Genetic as well as pharmacological inhibition of RPS6KA2 by the inhibitor BI-D1870 acted synergistically with erlotinib. By applying this synergistic lethality screen using a kinome-wide RNA interference--library approach, we identified RPS6KA2 as potential drug target whose inhibition synergistically enhanced the effect of erlotinib on tumor cell survival. This kinase therefore represents a promising drug candidate suitable for the development of novel inhibitors for pancreatic cancer therapy. [ABSTRACT FROM AUTHOR]

INTRODUCTION: WNT5A belongs to the Wnt family of secreted signaling molecules. Using transcriptional profiling, we previously identified WNT5A as target of the antiapoptotic transcription factor CUX1 and demonstrated high expression levels in pancreatic cancer. However, the impact of WNT5A on drug resistance and the signaling pathways employed by WNT5A remain to be elucidated. OBJECTIVES: This project aims to decipher the impact of WNT5A on resistance to apoptosis and the signaling pathways employed by WNT5A in pancreatic cancer. METHODS: The impact of WNT5A and its downstream effectors on tumor growth and drug resistance was studied in vitro and in xenograft models in vivo. Tissue microarrays of pancreatic cancer specimens were employed for immunohistochemical studies. RESULTS: Knockdown of WNT5A results in a significant increase in drug-induced apoptosis. In contrast, overexpression of WNT5A or addition of recombinant WNT5A mediates resistance to apoptosis in vitro. In our attempt to identify downstream effectors of WNT5A, we identified the transcription factor nuclear factor of activated T cells c2 (NFATc2) as transcriptional target of WNT5A signaling. NFATc2 confers a strong antiapoptotic phenotypemediating at least in part the effects of WNT5A on drug resistance and tumor cell survival. In vivo,WN T 5 A expression leads to resistance to gemcitabine-induced apoptosis in a xenograft model, which is paralleled by up-regulation of NFATc2. Both WNT5A and NFATc2 proteins are highly expressed in human pancreatic cancer tissues and their expression levels correlated significantly. CONCLUSION: We identified the WNT5A-NFATc2 axis as important mediator of drug resistance in pancreatic cancer. [ABSTRACT FROM AUTHOR]

Abstract: The 1st St. Gallen EORTC Gastrointestinal Cancer Conference 2012 Expert Panel clearly differentiated treatment and staging recommendations for the various gastroesophageal cancers. For locally advanced gastric cancer (⩾T3N+), the preferred treatment modality was pre- and postoperative chemotherapy. The majority of panel members would also treat T2N+ or even T2N0 tumours with a similar approach mainly because pretherapeutic staging was considered highly unreliable. It was agreed that adenocarcinoma of the gastroesophageal junction (AEG) is classified best according to Siewert et al. Preoperative radiochemotherapy (RCT) is the preferred treatment for AEG type I and II tumours. For AEG type III, i.e. tumours which may be considered as gastric cancer, perioperative chemotherapy is the majority approach. For resectable squamous cell cancer of the oesophagus a clear majority recommended radiochemotherapy followed by surgery as optimal approach, irrespective of tumour size. In contrast, definitive RCT was judged appropriate for advanced tumours with extended lymph node involvement (N2) or for cancers of the upper oesophagus. Additional recommendations are presented on the use of endosonography, PET-CT scan and laparoscopy for staging and on the preferred approach to surgery. [Copyright &y& Elsevier]

Abstract: Purpose: According to the CAO-/ARO-/AIO-94 trial of the German Rectal Cancer Study Group, pre-operative 5-fluorouracil (5-FU)-based long-term chemoradiotherapy (CT/RT) is recommended for patients with rectal cancer UICC stage II/III. However, despite the local benefit of neoadjuvant treatment, the overall prognostic value remains uncertain in comparison to adjuvant CT/RT. We assessed the impact of standardized pre-operative CT/RT and intratumoural mRNA levels and polymorphisms of the TS gene on histopathological tumour regression. Patients and methods: 40 patients with rectal cancer UICC stage II/III, receiving pre-operative 5-FU-based CT/RT followed by standardized surgery, including total mesorectal excision, were investigated. TS gene expression and TS polymorphisms of surgical specimens were correlated with the grade of histopathological tumour regression (0–4). Patients achieved regression grades 2–4 were determined as responders. Results: TS polymorphisms (5′-28bp repeat+G/C SNP and TS1494del6) could be determined in 39/40 (97.5%) and in 38/40 (95%) patients, respectively. Quantification of TS mRNA expression was successful in 36/40 (90%) patients. There was a highly significant linkage disequilibrium between 5′- and 3′-TS polymorphisms (p =0.0013). Interestingly, the majority of patients (82.1%) with 5′-TS genotypes known to be associated with low mRNA expression (2R/2R, 2R/3RC, 3RC/3RC) also possessed the TS1494del6 +6bp/+6bp genotype correlating with high TS mRNA expression. TS1494del6 polymorphism was significantly associated with TS mRNA expression. Patients with TS1494del6 −6bp/−6bp or −6bp/+6bp genotypes showed significantly lower mean TS mRNA expression with 0.55 (range:0.33;0.84) as compared to +6bp homozygotes with a mean expression of 0.90 (range:0.20;1.91) (p =0.025). Furthermore, all patients with TS 3′-UTR −6bp/−6bp or −6bp/+6bp genotype (11/11) were responders as compared to only 20/26 (77%) of patients with TS 3′-UTR +6bp/+6bp genotype (p =0.082). TS 5′-polymorphisms were not associated with neither tumour regression nor gene expression. Conclusion: Our data suggest that the TS1494del6 polymorphism may be an important predictor for histopathological tumour regression in UICC II/III rectal cancer patients receiving neoadjuvant 5-FU-based CT/RT. [Copyright &y& Elsevier]

Genetic aberrations are crucial in renal tumor progression. In this study, we describe loss of heterozygosity (LOH) and DNA-copy number abnormalities in clear cell renal cell carcinoma (cc-RCC) discovered by genome-wide single nucleotide polymorphism (SNP) arrays. Genomic DNA from tumor and normal tissue of 22 human cc-RCCs was analyzed on the Affymetrix GeneChip Human Mapping 10K Array. The array data were validated by quantitative polymerase chain reaction and immunohistochemistry. Reduced DNA copy numbers were detected on chromosomal arm 3p in 91%, on chromosome 9 in 32%, and on chromosomal arm 14q in 36% of the tumors. Gains were detected on chromosomal arm 5q in 45% and on chromosome 7 in 32% of the tumors. Copy number abnormalities were found not only in FHIT and VHL loci, known to be involved in renal carcinogenesis, but also in regions containing putative new tumor suppressor genes or oncogenes. In addition, microdeletions were detected on chromosomes 1 and 6 in genes with unknown impact on renal carcinogenesis. In validation experiments, abnormal protein expression of FOXP1 (on 3p) was found in 90% of tumors (concordance with SNP array data in 85%). As assessed by quantitative polymerase chain reaction, PARK2 and PACRG were down-regulated in 57% and 100%, respectively, and CSF1R was up-regulated in 69% of the cc-RCC cases (concordance with SNP array data in 57%, 33%, and 38%). Genome-wide SNP array analysis not only confirmed previously described large chromosomal aberrations but also detected novel microdeletions in genes potentially involved in tumor genesis of cc-RCC. [ABSTRACT FROM AUTHOR]