BACKGROUND & AIMS: CA IX (formerly MN protein) is a carbonic anhydrase isoenzyme whose expression is associated with human tumors. However, it has also been found in normal gastric mucosa. The aim of this study was to determine differences in complementary DNAs (cDNAs), to obtain an overview of distribution in the alimentary tract, and to obtain data on expression in tumors. METHODS: A CA9 cDNA isolated from a human stomach library was sequenced along with the cDNA derived from HeLa cells. Western blotting and immunohistochemical analyses of human and animal tissues were performed using CA IX-specific monoclonal antibody and rabbit antiserum to human CA II. RESULTS; Sequence analysis showed no differences between the stomach- and HeLa-derived cDNAs. CA IX was detected at the basolateral surface of gastric, intestinal, and gallbladder epithelia. In stomach tumor samples, expression of CA IX was lost or reduced. CONCLUSIONS: Differential distribution of CA IX in normal and tumor tissues is not associated with cDNA mutations. Evolutionary conservation in vertebrates as well as abundant expression of CA IX protein in normal human gastric mucosa, but not in derived tumors, indicate its physiological importance.
BACKGROUND & AIMS:CA IX (formerly MN protein) is a carbonic anhydrase isoenzyme whose expression is associated with humantumors. However, it has also been found in normal gastric mucosa. The aim of this study was to determine differences in complementary DNAs (cDNAs), to obtain an overview of distribution in the alimentary tract, and to obtain data on expression in tumors. METHODS: A CA9 cDNA isolated from a human stomach library was sequenced along with the cDNA derived from HeLa cells. Western blotting and immunohistochemical analyses of human and animal tissues were performed using CA IX-specific monoclonal antibody and rabbit antiserum to humanCA II. RESULTS; Sequence analysis showed no differences between the stomach- and HeLa-derived cDNAs. CA IX was detected at the basolateral surface of gastric, intestinal, and gallbladder epithelia. In stomach tumor samples, expression of CA IX was lost or reduced. CONCLUSIONS: Differential distribution of CA IX in normal and tumor tissues is not associated with cDNA mutations. Evolutionary conservation in vertebrates as well as abundant expression of CA IX protein in normal human gastric mucosa, but not in derived tumors, indicate its physiological importance.
Authors: A Kivelä; S Parkkila; J Saarnio; T J Karttunen; J Kivelä; A K Parkkila; A Waheed; W S Sly; J H Grubb; G Shah; O Türeci; H Rajaniemi Journal: Am J Pathol Date: 2000-02 Impact factor: 4.307
Authors: Gul N Shah; Timothy S Rubbelke; Joshua Hendin; Hien Nguyen; Abdul Waheed; James D Shoemaker; William S Sly Journal: Proc Natl Acad Sci U S A Date: 2013-04-15 Impact factor: 11.205
Authors: Cor Hj Lamers; Stefan Sleijfer; Sabine van Steenbergen; Pascal van Elzakker; Brigitte van Krimpen; Corrien Groot; Arnold Vulto; Michael den Bakker; Egbert Oosterwijk; Reno Debets; Jan W Gratama Journal: Mol Ther Date: 2013-02-19 Impact factor: 11.454