RT Journal Article SR Electronic T1 Salivary Gland Tumors in Transgenic Mice with Targeted PLAG1 Proto-Oncogene Overexpression JF Cancer Research JO Cancer Res FD American Association for Cancer Research SP 4544 OP 4553 DO 10.1158/0008-5472.CAN-04-4041 VO 65 IS 11 A1 Declercq, Jeroen A1 Van Dyck, Frederik A1 Braem, Caroline V. A1 Van Valckenborgh, Isabelle C. A1 Voz, Marianne A1 Wassef, Michel A1 Schoonjans, Luc A1 Van Damme, Boudewijn A1 Fiette, Laurence A1 Van de Ven, Wim J.M. YR 2005 UL http://cancerres.aacrjournals.org/content/65/11/4544.abstract AB Pleomorphic adenoma gene 1 (PLAG1) proto-oncogene overexpression is implicated in various human neoplasias, including salivary gland pleomorphic adenomas. To further assess the oncogenic capacity of PLAG1, two independent PLAG1 transgenic mouse strains were established, PTMS1 and PTMS2, in which activation of PLAG1 overexpression is Cre mediated. Crossbreeding of PTMS1 or PTMS2 mice with MMTV-Cre transgenic mice was done to target PLAG1 overexpression to salivary and mammary glands, in the P1-Mcre/P2-Mcre offspring. With a prevalence of 100% and 6%, respectively, P1-Mcre and P2-Mcre mice developed salivary gland tumors displaying various pleomorphic adenoma features. Moreover, histopathologic analysis of salivary glands of 1-week-old P1-Mcre mice pointed at early tumoral stages in epithelial structures. Malignant characteristics in the salivary gland tumors and frequent lung metastases were found in older tumor-bearing mice. PLAG1 overexpression was shown in all tumors, including early tumoral stages. The tumors revealed an up-regulation of the expression of two distinct, imprinted gene clusters (i.e., Igf2/H19 and Dlk1/Gtl2). With a latency period of about 1 year, 8% of the P2-Mcre mice developed mammary gland tumors displaying similar histopathologic features as the salivary gland tumors. In conclusion, our results establish the strong and apparently direct in vivo tumorigenic capacity of PLAG1 and indicate that the transgenic mice constitute a valuable model for pleomorphic salivary gland tumorigenesis and potentially for other glands as well. ©2005 American Association for Cancer Research.