title: Loss of miR-10a activates lpo and collaborates with activated Wnt signaling in inducing intestinal neoplasia in female mice.
abstract: miRNAs are small regulatory RNAs that, due to their considerable potential to target a wide range of mRNAs, are implicated in essentially all biological process, including cancer. miR-10a is particularly interesting considering its conserved location in the Hox cluster of developmental regulators. A role for this microRNA has been described in developmental regulation as well as for various cancers. However, previous miR-10a studies are exclusively based on transient knockdowns of this miRNA and to extensively study miR-10a loss we have generated a miR-10a knock out mouse. Here we show that, in the Apc(min) mouse model of intestinal neoplasia, female miR-10a deficient mice develop significantly more adenomas than miR-10(+/+) and male controls. We further found that Lpo is extensively upregulated in the intestinal epithelium of mice deprived of miR-10a. Using in vitro assays, we demonstrate that the primary miR-10a target KLF4 can upregulate transcription of Lpo, whereas siRNA knockdown of KLF4 reduces LPO levels in HCT-116 cells. Furthermore, Klf4 is upregulated in the intestines of miR-10a knockout mice. Lpo has previously been shown to have the capacity to oxidize estrogens into potent depurinating mutagens, creating an instable genomic environment that can cause initiation of cancer. Therefore, we postulate that Lpo upregulation in the intestinal epithelium of miR-10a deficient mice together with the predominant abundance of estrogens in female animals mainly accounts for the sex-related cancer phenotype we observed. This suggests that miR-10a could be used as a potent diagnostic marker for discovering groups of women that are at high risk of developing colorectal carcinoma, which today is one of the leading causes of cancer-related deaths.
authors.affiliation: Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Stadthagen
authors.forename: Disa
authors.initials: D
authors.lastname: Tehler
authors.forename: Nina Molin
authors.initials: NM
authors.lastname: Høyland-Kroghsbo
authors.forename: Jiayu
authors.initials: J
authors.lastname: Wen
authors.forename: Anders
authors.initials: A
authors.lastname: Krogh
authors.forename: Klaus T
authors.initials: KT
authors.lastname: Jensen
authors.forename: Eric
authors.initials: E
authors.lastname: Santoni-Rugiu
authors.forename: Lars H
authors.initials: LH
authors.lastname: Engelholm
authors.forename: Anders H
authors.initials: AH
authors.lastname: Lund
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D045325:HCT116 Cells; D006801:Humans; D007414:Intestinal Neoplasms / Q000235:genetics* / Q000473:pathology; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors / Q000096:biosynthesis*; D007784:Lactoperoxidase / Q000096:biosynthesis / Q000235:genetics*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D060449:Wnt Signaling Pathway / Q000235:genetics
chemical_list: C000715467:KLF4 protein, human; C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; C569259:MIRN10 microRNA, mouse; D035683:MicroRNAs; D007784:Lactoperoxidase