title: Multiple endocrine neoplasia type 1 deletion in pancreatic alpha-cells leads to development of insulinomas in mice.
abstract: The pancreatic alpha- and beta-cells are critical components in regulating blood glucose homeostasis via secretion of glucagon and insulin, respectively. Both cell types are typically localized in the islets of Langerhans. However, little is known about the roles of paracrine interactions that contribute to their physiological functions. The lack of suitable cell lines to study alpha- and beta-cells interactions have led us to develop an alpha-cell-specific Cre-expressing transgenic line utilizing a glucagon promoter sequence, the Glu-Cre transgenic mouse. Here, we demonstrate that the Glu-Cre could specifically and efficiently excise floxed target genes in adult islet alpha-cells. We further showed that deletion of the tumor suppressor gene, multiple endocrine neoplasia type 1 (Men1), in alpha-cells led to tumorigenesis. However, to our surprise, the lack of Men1 in alpha-cells did not result in glucagonomas but rather beta-cell insulinomas. Because deletion of the Men1 alleles was only present in alpha-cells, our data suggested that cross communication between alpha- and beta-cells contributes to tumorigenesis in the absence of Men1. Together, we believed that the new model systems described here will allow future studies to decipher cellular interactions between islet alpha- and beta-cells in a physiological context.
authors.affiliation: Tissue Array Research Program, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-8322, USA.
authors.forename: H-C Jennifer
authors.initials: HC
authors.lastname: Shen
authors.forename: Kris
authors.initials: K
authors.lastname: Ylaya
authors.forename: Klaus
authors.initials: K
authors.lastname: Pechhold
authors.forename: Arianne
authors.initials: A
authors.lastname: Wilson
authors.forename: Asha
authors.initials: A
authors.lastname: Adem
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Hewitt
authors.forename: Steven K
authors.initials: SK
authors.lastname: Libutti
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D017353:Gene Deletion; D055785:Gene Knockdown Techniques; D005934:Glucagon / Q000235:genetics / Q000378:metabolism; D050416:Glucagon-Secreting Cells / Q000378:metabolism*; D007340:Insulinoma / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D009928:Organ Specificity / Q000235:genetics; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: C484898:Men1 protein, mouse; D011518:Proto-Oncogene Proteins; D005934:Glucagon