Anti-WNT6 monoclonal antibody, clone FQS0355

Using a unique microarray platform for cytosine methylation profiling, the DNA methylation landscape of the human genome was monitored at more than 21 000 sites, including 79% of the annotated transcriptional start sites (TSS). Analysis of an oligodendroglioma derived cell line LN-18 revealed more than 4000 methylated TSS. The gene-centric analysis indicated a complex pattern of DNA methylation exists along each autosome, with a trend of increasing density approaching the telomeres. Remarkably, 2% of CpG islands (CGI) were densely methylated, and 17% had significant levels of 5 mC, whether or not they corresponded to a TSS. Substantial independent verification, obtained from 95 loci, suggested that this approach is capable of large scale detection of cytosine methylation with an accuracy approaching 90%. In addition, we detected large genomic domains that are also susceptible to DNA methylation reinforced inactivation, such as the HOX cluster on chromosome 7 (CH7). Extrapolation from the data suggests that more than 2000 genomic loci may be susceptible to methylation and associated inactivation, and most have yet to be identified. Finally, we report six new targets of epigenetic inactivation (IRX3, WNT10A, WNT6, RAR alpha, BMP7 and ZGPAT). These targets displayed cell line and tumor specific differential methylation when compared with normal brain samples, suggesting they may have utility as biomarkers. Uniquely, hypermethylation of the CGI within an IRX3 exon was correlated with over-expression of IRX3 in tumor tissues and cell lines relative to normal brain samples.

PLAG1 proto-oncogene overexpression has been causally linked to multiple tumors, highlighting its broad tumorigenic relevance. Here, the oncogenic potential of PLAG1 in mammary gland tumorigenesis was investigated in PLAG1 transgenic mice. To target mammary glands, mice of 2 independent PLAG1 transgenic strains, PTMS1 and PTMS2, in which PLAG1 expression can be modulated by Cre-mediation, were crossed with MMTV-Cre transgenic mice, resulting in P1-MCre and P2-MCre offspring, respectively. Hundred percentage of P1-MCre female mice showed mammary gland hyperplasia, caused by adenomyoepithelial adenosis, at 8 weeks. The tumorigenic process could not be studied further in P1-MCre mice, because concomitant fast-growing salivary gland tumors required euthanasia. Sixteen percentage of P2-MCre females developed mammary gland adenomyoepitheliomas within 30-45 weeks, and none displayed concomitant salivary gland tumors. To further study mammary gland tumorigenesis in PTMS1-derived mice, intercrossing with WAP-Cre transgenic mice, resulting in P1-WAPCre mice, was performed to target PLAG1 expression more specifically to mammary glands. Eighty percentage of such mice developed adenomyoepitheliomas within 53-88 weeks. All PLAG1-induced adenomyoepitheliomas revealed expression upregulation of Igf2/H19, Dlk1/Gtl2, Igf/bps and Wnt signaling genes (Wnt6, Cyclin D1). Collectively, these results establish the oncogenic potential of PLAG1 in mammary glands of mice and point towards contributing roles of Igf and Wnt signaling. (C) 2008 Wiley-Liss, Inc.