INTRODUCTION: It has been suggested that pyruvate carboxylase (PC) and carbamyl-phosphate synthetase I (CPS I) might be colocalized with carbonic anhydrase V (CA V), which is generally considered to provide HCO3- ions for PC and CPS I. AIM: To examine the immunohistochemical staining of endogenous biotin; of three mitochondrial biotin-binding enzymes (namely, PC, CPS I, and propionyl CoA-carboxylase); and of cytosolic acetyl CoA-carboxylase in pancreatic tissues. METHODOLOGY: Immunohistochemical analysis was performed on 23 samples of normal pancreas and 63 samples of neoplastic pancreatic tissues. RESULTS: It was found that the distribution of PC, CPS I, and endogenous biotin was not related to that of CA V but was similar to that of CA II in normal centroacinar cells, intercalated duct cells, and intralobular duct cells. In addition, PC was detected unexpectedly in delta-cells of islets. CONCLUSION: It seems likely that CA II plays a major role in the secretion of NaHCO3 into the pancreatic juice. Hence, it is possible that PC and CPS I in the centroacinar cells, intercalated duct cells, and intralobular duct cells are strongly activated and might use HCO3- ions provided by CA II and not by CA V. Among the pancreatic neoplasms examined, ductal adenocarcinomas exhibited significantly elevated immunoreactivity specific for the four biotin-binding enzymes.
INTRODUCTION: It has been suggested that pyruvate carboxylase (PC) and carbamyl-phosphate synthetase I (CPS I) might be colocalized with carbonic anhydrase V (CA V), which is generally considered to provide HCO3- ions for PC and CPS I. AIM: To examine the immunohistochemical staining of endogenous biotin; of three mitochondrial biotin-binding enzymes (namely, PC, CPS I, and propionyl CoA-carboxylase); and of cytosolic acetyl CoA-carboxylase in pancreatic tissues. METHODOLOGY: Immunohistochemical analysis was performed on 23 samples of normal pancreas and 63 samples of neoplastic pancreatic tissues. RESULTS: It was found that the distribution of PC, CPS I, and endogenous biotin was not related to that of CA V but was similar to that of CA II in normal centroacinar cells, intercalated duct cells, and intralobular duct cells. In addition, PC was detected unexpectedly in delta-cells of islets. CONCLUSION: It seems likely that CA II plays a major role in the secretion of NaHCO3 into the pancreatic juice. Hence, it is possible that PC and CPS I in the centroacinar cells, intercalated duct cells, and intralobular duct cells are strongly activated and might use HCO3- ions provided by CA II and not by CA V. Among the pancreatic neoplasms examined, ductal adenocarcinomas exhibited significantly elevated immunoreactivity specific for the four biotin-binding enzymes.
Authors: Müge Çeliktas; Ichidai Tanaka; Satyendra Chandra Tripathi; Johannes F Fahrmann; Clemente Aguilar-Bonavides; Pamela Villalobos; Oliver Delgado; Dilsher Dhillon; Jennifer B Dennison; Edwin J Ostrin; Hong Wang; Carmen Behrens; Kim-Anh Do; Adi F Gazdar; Samir M Hanash; Ayumu Taguchi Journal: J Natl Cancer Inst Date: 2017-03-01 Impact factor: 13.506