alcian-blue and Pancreatic-Neoplasms

A functional vacuolar adenosine triphosphatase (v-ATPase) complex regulates canonical Wnt/β-catenin signaling. The goal of this study was to identify the distribution of the v-ATPase in human and murine models of pancreatic intraepithelial neoplasms (PanINs) and assess its role in Wnt/β-catenin signaling.. We evaluated the immunolabeling pattern of the v-ATPase in human PanIN specimens and murine PanIN-1 and PanIN-2 lesions obtained from Ptf1a(Cre/+); LSL-Kras(G12D) mice. Wnt/β-catenin signaling was interrogated in primary PanIN cells by examining the phosphorylated levels of its surface coreceptor, low-density lipoprotein receptor-related protein-6 (LRP6), and its intracellular effector, nonphosphorylated β-catenin. The response of primary PanIN cells to epidermal growth factor (EGF) was assessed in the absence and presence of the v-ATPase inhibitor, concanamycin.. In advanced (PanIN-2), but not early (PanIN-1), lesions, the v-ATPase assumed a polarized phenotype. Blocking the v-ATPase disrupted Wnt/β-catenin signaling in primary PanIN cells despite significantly higher levels of the total and activated Wnt cell surface coreceptor, LRP6. Vacuolar adenosine triphosphatase blockade significantly decreased the total and activated levels of EGF receptor, a determinant of PanIN progression. The activation of EGF receptor and its intracellular mediator, p44/42 mitogen-activated protein kinase, was also reduced by v-ATPase blockade. This led to diminished proliferation in response to EGF ligand.. The v-ATPase regulates Wnt/β-catenin and EGF receptor signaling in PanINs.

Topics: Adenocarcinoma in Situ; Alcian Blue; Animals; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cell Polarity; Disease Progression; Epidermal Growth Factor; ErbB Receptors; Humans; Islets of Langerhans; Low Density Lipoprotein Receptor-Related Protein-6; Membrane Proteins; Mice; Mice, Mutant Strains; Mitogen-Activated Protein Kinase 3; Neoplasm Grading; Neoplasm Proteins; Pancreatic Neoplasms; Protein Transport; Staining and Labeling; Vacuolar Proton-Translocating ATPases; Wnt Signaling Pathway

Currently, the preoperative diagnosis of a pancreatic cyst is based on clinical and imaging findings, frequently in conjunction with chemical analysis of cyst fluid and cytologic evaluation. The purpose of these diagnostic tests is to distinguish benign from malignant cysts of the pancreas. Accordingly, it is imperative to distinguish pancreatic pseudocysts from their mimics. In this study, the authors explored the cytomorphologic features of pseudocyst of the pancreas and evaluated the role of Alcian blue and mucicarmine stains in the cytologic evaluation of pancreatic cysts.. Forty-two patients were identified who had an eventual diagnosis of pancreatic pseudocyst and had an endoscopic ultrasound-guided fine-needle aspirate available. Clinical and imaging findings and chemical analyses of cyst fluid were recorded. The cytologic preparations were evaluated for gastrointestinal contamination, inflammatory cells, mucin, and pigmented material. The cytomorphologic features of 110 neoplastic mucinous cysts (intraductal papillary-mucinous neoplasms/mucinous cystic neoplasms of the pancreas) were evaluated and compared with the pseudocysts.. The majority of patients (95%) had a prior episode of pancreatitis. On imaging, the pseudocysts were unilocular (92%). In 69% of cases, the endosonographic diagnosis was that of a pseudocyst. The mean carcinoembryonic antigen level was 41 ng/mL. In contrast, the cytopathologist rendered a definitive diagnosis of pseudocyst in only 10% of cases. The majority of smears (75%) revealed neutrophils and/or histiocytes. Atypical epithelial clusters were identified in 3 cases, 1 of which was diagnosed as suspicious for carcinoma. Yellow pigmented material, which was identified in 13 pseudocysts (31%), was not observed in neoplastic mucinous cysts. Alcian blue- and mucicarmine-positive material was identified in 64% and 40% of pseudocysts, respectively, and in 57% and 38% of neoplastic mucinous cysts, respectively.. The diagnosis of a pseudocyst depended primarily on clinical and imaging findings and on chemical analysis of cyst fluid. The cytologic features frequently were nonspecific. The presence of yellow pigmented material served as a surrogate marker of a pseudocyst. Special stains for mucin did not distinguish pseudocysts from neoplastic mucinous cysts.

Topics: Adult; Alcian Blue; Carcinoembryonic Antigen; Carmine; Cyst Fluid; Cytodiagnosis; Diagnosis, Differential; Endosonography; Epithelial Cells; Female; Histiocytes; Humans; Male; Middle Aged; Mucins; Neutrophils; Pancreas; Pancreatic Neoplasms; Pancreatic Pseudocyst; Reproducibility of Results; Sensitivity and Specificity; Staining and Labeling

In this study, our experience with five cases of mucinous cystadenocarcinoma of the pancreas is described, which was seen over a 13-yr period. The diagnosis in four of the cases was made from aspirated material that was obtained under computed tomography (CT) guidance and, in one case, following an intraoperative aspirate. In four cases, the tumor was found to be in the head of pancreas, whereas in one case, the neoplasm was located in the tail. All the cases were elderly male patients. As a result of our study, it is believed that aspiration cytodiagnosis of mucinous cystadenocarcinoma (a rare subtype of pancreatic carcinoma) can be made with confidence when performed intraoperatively or with imaging assistance. Also, aspiration cytology is a sensitive, specific, and relatively simple procedure that provides adequate material on which a confident diagnostic interpretation can be made of this uncommon neoplasm.

Topics: Adenocarcinoma; Aged; Alcian Blue; Biopsy, Needle; Carmine; Coloring Agents; Cystadenocarcinoma, Mucinous; Diagnosis, Differential; Eosine Yellowish-(YS); Hematoxylin; Humans; Male; Pancreas; Pancreatic Neoplasms; Staining and Labeling