title: Colorectal polyp model established by transplacental BMP4 RNAi.
abstract: Previous studies have shown that disruption of the bone morphogenetic protein (BMP) signaling pathway is an important cause of intestinal cancer in human and animal models. Thus, the purpose of this study was to construct a Balb/C model of colorectal polyps. Pregnant mice at 9.5 days gestation were injected via the tail vein with the pSES-Si BMP4 plasmid bearing a fluorochrome (DsRed) reporter, in order to silence the BMP4 gene in the first generation (F1); this group of mice was named the pSES-BMP4 group Intestinal fluorescence was detected at 1-, 4- and 8-week‑old F1 mice, and reverse transcription-polymerase chain reaction (RT-PCR) and western-blotting assays were used to determine changes in the expression of BMP4. A dissecting microscope and hematoxylin and eosin (H&E) staining were used to observe the cell morphology and appearance of the polyps. DsRed fluorescence was observed in the intestines of 1-week-old F1 mice of the pSES-BMP4 group. BMP4 expression at the mRNA and protein level was reduced in 1-, 4- and 8-week-old F1 mice (P<0.05). However, the level of Smad4 mRNA was only reduced in 8-week-old F1 mice (P<0.05). Multiple hyperplasic polyps emerged in the colon and rectum of the intestines of 4-week-old F1 mice in the pSES-BMP4 group. The size of colorectal polyps increased at 8 weeks, when vessels and polyp pedicles became apparent. In conclusion, silencing of the BMP4 gene using transplacental RNAi injection can induce formation of colorectal polyps in mice.
authors.affiliation: Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, P.R. China.
authors.forename: Xin
authors.initials: X
authors.lastname: Jin
authors.affiliation: General Hospital of Chongqing Iron and Steel Group, Chongqing 400081, P.R. China.
authors.forename: Zhongmei
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, P.R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Xiang
authors.affiliation: Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, P.R. China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Luo
authors.affiliation: Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, P.R. China.
authors.forename: Zhenghua
authors.initials: Z
authors.lastname: Guo
authors.affiliation: Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, P.R. China.
authors.forename: Xionghui
authors.initials: X
authors.lastname: Ding
authors.affiliation: Ministry of Education Key Laboratory of Child Development and Disorders, Children's Hospital of Chongqing Medical University, Chongqing 400014, P.R. China.
authors.forename: Xianqing
authors.initials: X
authors.lastname: Jin
mesh_terms: D000818:Animals; D055415:Bone Morphogenetic Protein 4 / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D003111:Colonic Polyps / Q000378:metabolism* / Q000473:pathology; D015179:Colorectal Neoplasms / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D010920:Placenta / Q000378:metabolism*; D011247:Pregnancy; D034622:RNA Interference; D012333:RNA, Messenger / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D051901:Smad4 Protein / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism
chemical_list: D055415:Bone Morphogenetic Protein 4; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D051901:Smad4 Protein