Widespread somatic loss of heterozygosity as a possible marker of disease aggressiveness in metastatic well differentiated pancreatic neuroendocrine tumors.

2018 ◽  
Vol 36 (4_suppl) ◽  
pp. 275-275
Author(s):  
Omobolaji Oyekunle Akala ◽  
Ronak Shah ◽  
Brian R. Untch ◽  
Virginia Kelly ◽  
Joanne F. Chou ◽  
...  

275 Background: To assess the utility of molecular profiling to predict tumor biology, we performed next-generation sequencing (NGS) of metastatic well differentiated (WD) pancreatic neuroendocrine tumors (panNETs) in the routine practice setting. Our institutional NGS platform allows for evaluation of genetic alterations that contribute to tumorigenesis (sequence variants, copy number alterations, insertions/deletions, select rearrangements) as well as somatic loss of heterozygosity (LOH). Methods: NGS was performed using MSK-IMPACT, a matched tumor-normal sequencing platform that interrogates 468 cancer-related genes. LOH for all cases was determined by analysis of total, allele-specific, and integer DNA copy number genome-wide using the FACETS algorithm. Results: Since 2014, NGS has been performed in 96 tumor samples from 80 patients. The most commonly altered genes were MEN1 (56%), DAXX (40%), ATRX (25%), and TSC2 (25%). LOH was highly prevalent, identified in 51/96 samples (53%). A significant association (q-value < 0.05) was noted between LOH and the presence of altered MEN1, DAXX, PTEN, or TSC2. LOH was recurrently observed in chromosomes 1, 2, 3, 6, 8, 10, 11, 15, 16, 21, and 22. Since MEN1 alterations predict improved outcome, comparison was made between patients with LOH present/MEN1 wild type (WT) tumors (n = 16) and LOH absent/MEN1 altered tumors (n = 21); inferior overall survival (OS) was noted with LOH present/MEN1 WT status (p < 0.01). High grade pathology was observed in 6/16 (38%) LOH present/MEN1 WT tumors and in 1/21 (5%) LOH absent/MEN1 altered tumors (p < 0.0001). The mean Ki-67 index of LOH present/MEN1 WT tumors was 22% and that of LOH absent/MEN1 altered tumors was 9%. Conclusions: This is the first study to report widespread somatic LOH in metastatic WD panNETs. PanNETs appear to exhibit more LOH overall than virtually any tumor type studied. In this cohort, LOH was a prognostic marker of inferior OS and was associated with more aggressive pathologic features. LOH warrants further investigation as it may help better characterize these clinically heterogeneous tumors.

2018 ◽  
pp. 1-18 ◽  
Author(s):  
Nitya Raj ◽  
Ronak Shah ◽  
Zsofia Stadler ◽  
Semanti Mukherjee ◽  
Joanne Chou ◽  
...  

Purpose We assessed the usefulness of real-time molecular profiling through next-generation sequencing (NGS) in predicting the tumor biology of advanced pancreatic neuroendocrine tumors (panNETs) and in characterizing genomic evolution. Methods Patients with metastatic panNETs were recruited in the routine clinical practice setting (between May 2014 and March 2017) for prospective NGS of their tumors as well as for germline analysis using the Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) sequencing platform. When possible, NGS was performed at multiple time points. Results NGS was performed in 96 tumor samples from 80 patients. Somatic alterations were identified in 76 of 80 patients (95%). The most commonly altered genes were MEN1 (56%), DAXX (40%), ATRX (25%), and TSC2 (25%). Alterations could be defined in pathways that included chromatin remodeling factors, histone methyltransferases, and mammalian target of rapamycin pathway genes. Somatic loss of heterozygosity was particularly prevalent (55 of 95 tested samples [58%]), and the presence of loss of heterozygosity resulted in improved overall survival (P = .06). Sequencing of pre- and post-treatment samples revealed tumor-grade progression; clonal evolution patterns were also seen (molecular resistance mechanisms and chemotherapy-associated mutagenesis). Germline genetic analysis identified clinically actionable pathogenic or likely pathogenic variants in 14 of 88 patients (16%), including mutations in high-penetrance cancer susceptibility genes ( MEN1, TSC2, and VHL). Conclusion A clinical NGS platform reveals pertubations of biologic pathways in metastatic panNETs that may inform prognosis and direct therapies. Repeat sequencing at disease progression reveals increasing tumor grade and genetic evolution, demonstrating that panNETs adopt a more aggressive behavior through time and therapies. In addition to frequent somatic mutations in MEN1 and TSC2, germline mutations in these same genes underlie susceptibility to panNETs and highlight the need to re-evaluate whether germline genetic analysis should be performed for all patients with panNETs.


2019 ◽  
Vol 240 (3) ◽  
pp. R73-R96 ◽  
Author(s):  
Manuel D Gahete ◽  
Juan M Jiménez-Vacas ◽  
Emilia Alors-Pérez ◽  
Vicente Herrero-Aguayo ◽  
Antonio C Fuentes-Fayos ◽  
...  

Endocrine and neuroendocrine tumors comprise a highly heterogeneous group of neoplasms that can arise from (neuro)endocrine cells, either from endocrine glands or from the widespread diffuse neuroendocrine system, and, consequently, are widely distributed throughout the body. Due to their diversity, heterogeneity and limited incidence, studying in detail the molecular and genetic alterations that underlie their development and progression is still a highly elusive task. This, in turn, hinders the discovery of novel therapeutic options for these tumors. To circumvent these limitations, numerous mouse models of endocrine and neuroendocrine tumors have been developed, characterized and used in preclinical, co-clinical (implemented in mouse models and patients simultaneously) and post-clinical studies, for they represent powerful and necessary tools in basic and translational tumor biology research. Indeed, different in vivo mouse models, including cell line-based xenografts (CDXs), patient-derived xenografts (PDXs) and genetically engineered mouse models (GEMs), have been used to delineate the development, progression and behavior of human tumors. Results gained with these in vivo models have facilitated the clinical application in patients of diverse breakthrough discoveries made in this field. Herein, we review the generation, characterization and translatability of the most prominent mouse models of endocrine and neuroendocrine tumors reported to date, as well as the most relevant clinical implications obtained for each endocrine and neuroendocrine tumor type.


2021 ◽  
Author(s):  
Jane E. Rogers ◽  
Michael Lam ◽  
Daniel M. Halperin ◽  
Cecile G. Dagohoy ◽  
James C. Yao ◽  
...  

We evaluated outcomes of treatment with 5-fluorouracil (5-FU), doxorubicin, and streptozocin (FAS) in well-differentiated pancreatic neuroendocrine tumors (PanNETs) and its impact on subsequent therapy (everolimus or temozolomide). Advanced PanNET patients treated at our center from 1992 to 2013 were retrospectively reviewed. Patients received bolus 5-FU (400 mg/m2), streptozocin (400 mg/m2) (both IV, days 1-5) and doxorubicin (40 mg/m2 IV, day 1) every 28 days. Overall response rate (ORR) was assessed using RECIST version 1.1. Of 243 eligible patients, 220 were evaluable for ORR, progression-free survival (PFS), and toxicity. Most (90%) had metastatic, nonfunctional PanNETs; 14% had prior therapy. ORR to FAS was 41% (95% confidence interval [CI]: 36-48%). Median follow-up was 61 months. Median PFS was 20 (95% CI: 15-23) months; median overall survival (OS) was 63 (95% CI: 60-71) months. Cox regression analyses suggested improvement with first-line vs subsequent lines of FAS therapy. Main adverse events ≥ grade 3 were neutropenia (10%) and nausea/vomiting (5.5%). Dose reductions were required in 32% of patients. Post-FAS everolimus (n=108; 68% second line) had a median PFS of 10 (95% CI: 8-14) months. Post-FAS temozolomide (n=60; 53% > fourth line) had an ORR of 13% and median PFS of 5.2 (95% CI: 4-12) months. In this largest reported cohort of PanNETs treated with chemotherapy, FAS demonstrated activity without significant safety concerns. FAS did not appear to affect subsequent PFS with everolimus; this sequence is being evaluated prospectively. Responses were noted with subsequent temozolomide-based regimens although PFS was possibly limited by line of therapy.


2021 ◽  
Author(s):  
Marc Diedisheim ◽  
Solène Dermine ◽  
Anne Jouinot ◽  
Amandine Septier ◽  
Sébastien Gaujoux ◽  
...  

Duodenopancreatic neuroendocrine tumors (DPNETs) aggressiveness is heterogeneous. Tumor grade and extension are commonly used for prognostic determination. Yet, grade classes are empirically defined, with regular up-dates changing the definition of classes. Genomic screening may provide more objective classes, and reflect tumor biology. The aim of this study was to provide a transcriptome classification of DPNETs. We included 66 DPNETs, covering the entire clinical spectrum of the disease in terms of secretion, grade, and stage. Three distinct molecular groups were identified, associated with distinct outcome (log-rank p<0.01): (i) better-outcome DPNETs with pancreatic beta-cell signature. This group was mainly composed of well-differentiated, grade 1 insulinomas; (ii) poor-outcome DPNETs with pancreatic alpha-cell and hepatic signature. This group included all neuroendocrine carcinomas and grade 3 DPNETs, but also some grade 1 and grade 2 DPNETs; and (iii) intermediate-outcome DPNETs with pancreatic exocrine and progenitor signature. This group included grade 1 and grade 2 DPNETs, with some insulinomas. Fibrinogen gene FGA expression was one of the top most expressed liver gene. FGA expression was associated with disease-free survival (HR=1.13, p=0.005), and could be validated on two independent cohorts. This original pathophysiologic insight provides new prognostic classification perspectives.


Endocrine ◽  
2017 ◽  
Vol 57 (3) ◽  
pp. 503-503
Author(s):  
Federica Grillo ◽  
Luca Valle ◽  
Diego Ferone ◽  
Manuela Albertelli ◽  
Maria Pia Brisigotti ◽  
...  

2018 ◽  
Vol 46 (4) ◽  
pp. 314-322
Author(s):  
V. V. Delektorskaya ◽  
O. N. Solov'eva ◽  
G. Yu. Chemeris ◽  
Yu. I. Patyutko

Background:Well-differentiated pancreatic neuroendocrine tumors (pNETs) represent a group of rare epithelial neoplasms with a highly variable clinical course. AKT1 is one of the most frequently activated protein kinases in pNETs, which promotes the tumor growth and is of interest as a prognostic factor and a target for new treatment approaches.Aim:To study the expression of the phosphorylated variant of AKT1-kinase (p-AKT1) in primary pNETs and their liver metastases and to correlate the results with various clinical and pathological parameters and the disease prognosis.Materials and methods:P-AKT1 expression was studied by the immunohistochemical analysis of the primary lesions and liver metastases in 52 pNETs patients.Results:A high level of cytoplasmic and/or nuclear immunoreactivity was detected in 24/52 of the primary pNETs (46.2%) and in 16/27 of their liver metastases (59.3%). p-AKT1 expression was observed in 3 (21.4%) of NET grade (G) 1, in 14 (46.7%) of NET G2, and in 7 (87.5%) of NET G3. p-AKT1 expression was more frequently identified in pNET G3 category and increased during the tumor progression in metachronous liver metastases, as compared to the corresponding primary tumor. In addition, p-AKT1 positivity was significantly associated with an increase of grade from G1 to G3 (p = 0.004), the Ki-67 index (p = 0.029), the pTNM stage (p = 0.0008), perineural invasion (p = 0.031) and a decrease in disease-free survival (p = 0.05).Conclusion:The results suggest that p-АКТ1 plays an important role in the pathogenesis of pNETs and may be an additional criterion for assessment of the prognosis and treatment effectiveness in this type of tumors.


Oncogenesis ◽  
2021 ◽  
Vol 10 (12) ◽  
Author(s):  
Angela M. Carter ◽  
Nilesh Kumar ◽  
Brendon Herring ◽  
Chunfeng Tan ◽  
Rachael Guenter ◽  
...  

AbstractPancreatic neuroendocrine tumors (PanNETs) are a heterogeneous population of neoplasms that arise from hormone-secreting islet cells of the pancreas and have increased markedly in incidence over the past four decades. Non-functional PanNETs, which occur more frequently than hormone-secreting tumors, are often not diagnosed until later stages of tumor development and have poorer prognoses. Development of successful therapeutics for PanNETs has been slow, partially due to a lack of diverse animal models for pre-clinical testing. Here, we report development of an inducible, conditional mouse model of PanNETs by using a bi-transgenic system for regulated expression of the aberrant activator of Cdk5, p25, specifically in β-islet cells. This model produces a heterogeneous population of PanNETs that includes a subgroup of well-differentiated, non-functional tumors. Production of these tumors demonstrates the causative potential of aberrantly active Cdk5 for generation of PanNETs. Further, we show that human PanNETs express Cdk5 pathway components, are dependent on Cdk5 for growth, and share genetic and transcriptional overlap with the INS-p25OE model. The utility of this model is enhanced by the ability to form tumor-derived allografts. This new model of PanNETs will facilitate molecular delineation of Cdk5-dependent PanNETs and the development of new targeted therapeutics.


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