Wilms tumor is the most frequent renal neoplasm in children, but our understanding of its genetic basis is still limited. We performed cDNA microarray experiments using 63 primary Wilms tumors with the aim of detecting new candidate genes associated with malignancy grade and tumor progression. All tumors had received preoperative chemotherapy as mandated by the SIOP protocol, which sets this study apart from related approaches in the Unites States that are based on untreated samples. The stratification of expression data according to clinical criteria allowed a rather clear distinction between different subsets of Wilms tumors. Clear-cut differences in expression patterns were discovered between relapse-free as opposed to relapsed tumors and tumors with intermediate risk as opposed to high risk histology. Several differentially expressed genes, e.g. TRIM22, CENPF, MYCN, CTGF, RARRES3 and EZH2, were associated with Wilms tumor progression. For a subset of differentially expressed genes, microarray data were confirmed by real-time RT-PCR on the original set of tumors. Interestingly, we found the retinoic acid pathway to be deregulated at different levels in advanced tumors suggesting that treatment of these tumors with retinoic acid may represent a promising novel therapeutic approach. ' 2005 Wiley-Liss, Inc.

The WNT/beta-catenin pathway is involved in numerous human cancers. Mutations of the CTNNB1 (beta-catenin) gene have also been detected in a subset of pediatric Wilms tumors, but the target genes of the deregulated WNT/beta-catenin pathway in these tumors have yet to be identified. To compare gene expression profiles of Wilms tumors with and without mutations of CTNNB1, we used 11.5-k cDNA microarrays. Most of the tumors (86%) had received preoperative chemotherapy as mandated by the European SIOP protocol. The comparison between Wilms tumors with and without CTNNB1 mutations revealed several target genes specifically deregulated in CTNNB1-mutated Wilms tumors. Among these, PITX2, APCDD1, and two members of the endothelin axis (EDN3 and EDNRA) are directly activated downstream targets of the WNT/beta-catenin pathway that may enhance proliferation of these tumor cells. In addition, several upstream inhibitors of WNT/beta-catenin signaling like WIF1 and PRDC were also strongly up-regulated in the CTNNB1-mutated Wilms tumors. This overexpression may be a negative feedback mechanism in tumors with uncontrolled WNT signaling. Moreover, we identified deregulated genes in both the retinoic acid and the RAS pathways, such as ATX/ENPP2 and RIS1, suggesting an association between these two pathways with that of WNT. In addition, the strong representation of muscle-related genes in the expression profile of CTNNB1-mutated Wilms tumors corresponded to histologically detectable areas of myomatous cells in these tumors that displayed intense and preferential nuclear beta-catenin antibody staining. This article contains Supplementary Material available at http://www.interscience.wiley.com/jpages/1045-2257/suppmat.

Allele loss of chromosome arms 11q and 16q in Wilms tumors has been associated with different clinical parameters in prior studies. To substantiate these findings in a large collection of tumors treated according to the GPOH/SIOP protocol and to narrow down critical regions, we performed loss of heterozygosity (LOH) analyses of chromosome arms 11q and 16q on 225 Wilms tumors. On chromosome arm 11q an overall rate of allele loss of 19.6% (44 of 225 tumors) was found using eleven markers that were almost evenly distributed along the long arm. Chromosome arm 16q was analyzed with six markers selected from gene-rich regions that identified an LOH rate of 18.4% (41/223). Evaluation of LOH with respect to clinical data revealed significant associations of LOH 11q with histology: LOH 11q was 3-4 times more frequent in mixed type and diffuse anaplastic tumors. In contrast, epithelial as well as stromal type tumors never exhibited allele loss on 11q. Furthermore, a significant correlation with tumor recurrence and death was detected, but only for tumors that lost the entire long arm of chromosome 11. Similarly, LOH 16q was correlated with higher risks of later relapse, especially in tumors with complete loss of the long arm. Hence, analyses of LOH on 11q and 16q appear to be helpful to identify tumors with a higher risk of relapse and adverse outcome, which need adjusted therapeutic approaches. This article contains Supplementary Material available at

Cytokines, eicosanoids, and lactoferrin are involved in the mammary gland's immune response to invading microorganisms. The goal of this work was to investigate the synthesis of these immunologically important factors in somatic milk cells, blood cells, and mammary tissue of cows with different somatic cell count levels, i.e., different immunological activity. On the level of mRNA expression, the cytokine tumor necrosis factor alpha (TNFalpha), lactoferrin (Lf), and specific key enzymes of leukotriene and prostaglandin biosynthesis, 5-lipoxygenase (5-LO), and cyclooxygenase-1 (COX-1) and -2 (COX-2), respectively, were determined. All 15 experimental cows were clinically healthy with no visible mammary disease. Eight cows were defined as control group with all quarters <150,000 cells/ml (C), whereas seven cows had partially elevated quarter somatic cell counts, with at least one quarter >150,000 cells/ml (H) and one quarter <150,000 cells/ml (L). Total quarter milk from one quarter of control group and from two quarters of cows with partially elevated cell counts (one of H and one of L) was collected at one milking and a blood sample was taken simultaneously. In addition, mammary tissue samples were taken from the respective quarters on the following day during slaughter. Total RNA from milk, blood, and tissue cells was isolated and reverse transcription and quantitative polymerase chain reaction was carried out. All factors investigated were not significantly different between groups in blood cells and between C and L quarters in milk cells and mammary tissue. TNFalpha and COX-2 mRNA expression was higher in milk cells and mammary tissue of H than in L quarters, except for COX-2 in mammary tissue. Generally, TNFalpha and COX-2 showed their highest expression in milk cells, 5-LO in blood cells, whereas lactoferrin was mainly expressed by the mammary tissue. COX-1 was similarly expressed in all tested samples.

Background: Coordinated differentiation of the endometrial compartments in the second half of the menstrual cycle is a prerequisite for the establishment of pregnancy. Endometrial stromal cells (ESC) decidualize under the influence of ovarian progesterone to accommodate implantation of the blastocyst and support establishment of the placenta. Studies into the mechanisms of decidualization are often hampered by the lack of primary ESC. Here we describe a novel immortalized human ESC line.