title: Netrin-1 controls colorectal tumorigenesis by regulating apoptosis.
abstract: The expression of the protein DCC (deleted in colorectal cancer) is lost or markedly reduced in numerous cancers and in the majority of colorectal cancers due to loss of heterozygosity in chromosome 18q, and has therefore been proposed to be a tumour suppressor. However, the rarity of mutations found in DCC, the lack of cancer predisposition of DCC mutant mice, and the presence of other tumour suppressor genes in 18q have raised doubts about the function of DCC as a tumour suppressor. Unlike classical tumour suppressors, DCC has been shown to induce apoptosis conditionally: by functioning as a dependence receptor, DCC induces apoptosis unless DCC is engaged by its ligand, netrin-1 (ref. 3). Here we show that inhibition of cell death by enforced expression of netrin-1 in mouse gastrointestinal tract leads to the spontaneous formation of hyperplastic and neoplastic lesions. Moreover, in the adenomatous polyposis coli mutant background associated with adenoma formation, enforced expression of netrin-1 engenders aggressive adenocarcinomatous malignancies. These data demonstrate that netrin-1 can promote intestinal tumour development, probably by regulating cell survival. Thus, a netrin-1 receptor or receptors function as conditional tumour suppressors.
authors.affiliation: Apoptosis/Differentiation Laboratory-Equipe labellisée La Ligue-Molecular and Cellular Genetic Center, CNRS UMR 5534, University of Lyon, 69622 Villeurbanne, France.
authors.forename: Laetitia
authors.initials: L
authors.lastname: Mazelin
authors.forename: Agnès
authors.initials: A
authors.lastname: Bernet
authors.forename: Christelle
authors.initials: C
authors.lastname: Bonod-Bidaud
authors.forename: Laurent
authors.initials: L
authors.lastname: Pays
authors.forename: Ségolène
authors.initials: S
authors.lastname: Arnaud
authors.forename: Christian
authors.initials: C
authors.lastname: Gespach
authors.forename: Dale E
authors.initials: DE
authors.lastname: Bredesen
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Scoazec
authors.forename: Patrick
authors.initials: P
authors.lastname: Mehlen
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D011125:Adenomatous Polyposis Coli / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000818:Animals; D017209:Apoptosis; D002470:Cell Survival; D002471:Cell Transformation, Neoplastic; D002645:Chickens; D015179:Colorectal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009154:Mutation / Q000235:genetics; D009414:Nerve Growth Factors / Q000235:genetics / Q000378:metabolism*; D000075388:Netrin-1; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000502:physiology
chemical_list: D009414:Nerve Growth Factors; C000617353:Ntn1 protein, mouse; D012333:RNA, Messenger; D025521:Tumor Suppressor Proteins; D000075388:Netrin-1