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Introduction: Neuroendocrine tumors (NETs) frequently have a genetic basis, and the range of genes implicated in NET development continues to expand. Application of targeted gene panels (TGPs) in next-generation sequencing is a central strategy for elucidating novel variants associated with NET development., Methods: In this study, we conducted comprehensive molecular genetic analyses using TGP on a cohort of 93 patients diagnosed with various NETs subtypes, mainly accompanied by various endocrine syndromes: insulinoma (n = 26), pheochromocytoma and paraganglioma (PPGL) (n = 38), parathyroid adenoma (n = 18, including three with insulinoma), and NETs of other locations (n = 14). The TGP encompassed genes linked to diverse NETs and other hereditary endocrine disorders, with subsequent variant classification according to the American College of Medical Genetics and Genomics guidelines., Results: Among the identified variants, 20 were found in genes previously linked to specific tumor types, and 10 were found in genes with a limited likelihood and unclear molecular mecanisms of association with observed NETs. Remarkably, 13 variants were discovered in genes not previously associated with the NETs observed in our patients. These genes, such as ABCC8, KCNJ11, KLF11, HABP2, and APC, were implicated in insulinoma; ZNRF3, GNAS, and KCNJ5 were linked with PPGL; parathyroid adenomas were related to variants in SDHB and TP53; while NETs of other locations displayed variants in APC and ABCC8., Conclusion: Our study demonstrates that utilizing broad TGP in examining patients with various functioning NETs facilitates the identification of new germinal variants in genes that may contribute to the diseases. The verification of revealed findings requires research in vaster sample., (© 2024 The Author(s). Published by S. Karger AG, Basel.)

Background: Early diagnosis of pancreatic ductal adenocarcinoma (PDAC) has been a longstanding challenge. The prognosis of patients with PDAC depends on the stage at diagnosis. It is necessary to identify biomarkers for the detection and differentiation of pancreatic tumors and optimize PDAC sample preparation procedures for DNA and RNA analysis. Most molecular studies are done using paraffin-embedded blocks; however, the integrity of DNA and RNA is often compromised in this format. Moreover, RNA isolated from human pancreatic tissue samples is generally of low quality, in part, because of the high concentration of endogenous pancreatic RNAse activity present., Aim: To assess the potential of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) to obtain specimens from pancreatic neoplasms for subsequent RNA molecular profiling, including next-generation sequencing (NGS)., Methods: Thirty-four EUS-FNA samples were included in this study: PDAC ( n = 15), chronic pancreatitis ( n = 5), pancreatic cysts ( n = 14), mucinous cysts (mucinous cystic neoplasia/intraductal papillary mucinous neoplasia) n = 7, serous cystic neoplasms n = 5, and pseudocysts n = 2. Cyst material consisted of cyst fluid and cyst wall samples obtained by through-the-needle biopsy (TTNB). Samples were stored at -80 °C until analysis. RNA purity (A260/230, A260/280 ratios), concentration, and integrity (RIN) were assessed. Real-time polymerase chain reaction was conducted on all samples, and small RNA libraries were prepared from solid mass samples., Results: RNA was successfully extracted from 29/34 (85%) EUS-FNA samples: 100% pancreatic adenocarcinoma samples, 100% chronic pancreatitis samples, 70% pancreatic fluid cyst samples, and 50% TTNB samples. The relative expression of GAPDH and HPRT were obtained for all successfully extracted RNA samples ( n = 29) including low-quality RNA specimens. Low concentration and nonoptimal RIN values (no less than 3) of RNA extracted from EUS-FNA samples did not prevent NGS library preparation. The suitability of cyst fluid samples for RNA profiling varied. The quality of RNA extracted from mucinous cyst fluid had a median RIN of 7.7 (5.0-8.2), which was compatible with that from solid neoplasms [6.2 (0-7.8)], whereas the quality of the RNA extracted from all fluids of serous cystic neoplasms and TTNB samples had a RIN of 0., Conclusion: The results demonstrate the high potential of EUS-FNA material for RNA profiling of various pancreatic lesions, including low-quality RNA specimens., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)