Truncated mouse adenomatous polyposis coli reduces connexin32 content and increases matrilysin secretion from Paneth cells.
Heterozygous mutations in adenomatous polyposis coli (APC) is an early event in inheritable and sporadic colon cancer development. We recently found reduced connexin (Cx43) expression in intestinal cell lines with heterozygous Apc mutation. In this study we investigated Cx expression and the role of one mutated Apc allele in epithelia of multiple intestinal neoplasia (Min) mouse intestines by immunohistochemistry. Cx43 was not expressed in intestinal epithelia of Min and wild-type mice. Cx32 was specifically expressed in enterochromaffin cells in both mice types, and in Paneth cells of wild-type mice. In contrast, Min mice had nearly undetectable level of Cx32 in Paneth cells. Isolated small intestinal crypts from Min mice had markedly increased secretion of both lysozyme and matrilysin compared with wild-type mice. Absence of matrilysin in Min mice reduces adenoma development. Reduced Cx32 and increased matrilysin secretion from Paneth cells could be important to neoplastic development in the intestine.
Husøy
Trine
T
Department of Food Toxicology, Norwegian Institute of Public Health, P.O. Box 4404 Nydalen, NO-0403 Oslo, Norway. trine.husoy@fhi.no
Ølstørn
Hege B
HB
Knutsen
Helle K
HK
Løberg
Else Marit
EM
Cruciani
Véronique
V
Mikalsen
Svein-Ole
SO
Goverud
Ingeborg L
IL
Alexander
Jan
J
D011125:Adenomatous Polyposis Coli / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D018031:Connexin 43 / Q000378:metabolism*; D017630:Connexins / Q000378:metabolism*; D007150:Immunohistochemistry / Q000379:methods; D020783:Matrix Metalloproteinase 7 / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D019879:Paneth Cells / Q000378:metabolism*; D000097002:Gap Junction beta-1 Protein
D018031:Connexin 43; D017630:Connexins; D020783:Matrix Metalloproteinase 7; D000097002:Gap Junction beta-1 Protein