The Introdiction And Reproduction Of MMTV-Wnt-1 Transgenic Mice And Its Biological Features

Wnt gene regulates Wnt signaling that plays a role in embryogenesis and oncogensis. To research the relation between Wnt- 1 gene and mammary tumor, MMTV-Wnt-l transgenic mice in FVB strain came from NIH(National Institute of Healthy) were used for reproduction and the study of its biological features. The reproductive system was constructed as the following: (i) ~ W/+ X ~ +/-i- ;(ii) ~ w/?X ~ w/? all pups were forster-nursed on normal female. Tail DNA from weanling mice was analyzed by PCR(polymerase chain reaction) and 45 transgenic mice 憕ere generated. High concentration ethylene glycol (EG-8, 8mol/L) and galactose( I . 7mol/L) were used as a cryoprotectant and thawing diluents for embryo cryopreservation by vitrification in MMTV-Wnt-l transgenic mice. It has the best results of cryopreservation if those embryos kept balance in EG-2 (2mol/L) for 4-6 minute before freeze and thawing 3-5 minute in galactose. The percentage of embryos cryopreserved and retrieve is 88.42%; there is 90.40% of these embryos develop and 77.8% developing to hatch blastocysts. After these development embryos were transferred pseudopregnancy mouse. 29 mice were uenerated and 13 of 29 were positive mouse on the PCR test. That 7 of 17 female mice developed mammary tumor during 7 months demonstrated the expression of \Vnt-l transgene using MMTV-LTR enhancer had high levels in mammary and then leads to adenocarcinomas. Tumefaction occured in spleen and liver while no obvious lesion appeared in other organs. Adenocarcinomas was further identified by histopathology. No metastasis occurred at the time mammary tumors were detected. The tissue mass from tumors was transplanted into Subcutaneous sites of 7 nude mice .Transplanted-tumors formatted in 6 of 7 and were marked with the similar bio~ogieal features of primal tumor.