BMC Cancer 2005, 5:3 http://www.biomedcentral.com/1471-2407/5/3 widely expressed. In most cases, the levels of HIG2 in the tumours and the associated normal tissue controls were similar. HIG2 was, however, strongly and consistently downregulated in the majority of the kidney and stomach tumours analysed. This represents an significant valida- tion of our in vitro findings in human tumours, and sug- gests that HIG2 may exert a tumour suppressive effect in vivo. Human HIG2 is located on 7q32.2, a commonly deleted region in several tumour types, most prominently leukaemias and lymphomas [57]. Deletion analysis of 7q in a panel of patients with Splenic Lymphoma with Villous Lymphocytes by Catovsky and colleagues suggests that a critical tumour suppressor is located on 7q32 [58]. Conclusions The identification of this panel of candidate target genes for this clinically important signal transduction pathway adds to those identified by other workers in a variety of model systems and suggests that, as well as promoting tumour cell proliferation and survival in a cell autonomous manner, this activation of this pathway is likely to have a series of non-cell autonomous effects. Here we have focussed on the identification of Wnt/β-cat- enin target genes that are either secreted signalling mole- cules or receptors. It is likely that such targets are involved in mediating autocrine proliferation, promotion of angio- genesis and the mediation of reciprocal communication between Wnt/β-catenin tumours and their microenviron- mental milieu. Competing interests The authors declare that they have no competing interests. Authors' contributions PK carried out all of the experimental procedures and drafted the manuscript. PK, TE and AA contributed to the design of the study. All authors read and approved the final version of this manuscript. Additional material Additional File 1 cDNA microarray dataset: HC11 ∆Nβ-catenin v. HC11 lacZ. This file contains the dataset from the Incyte GEM1 cDNA microarray comparison between HC11 cells overexpressing ∆Nβ-catenin (Probe 1) and β-galac- tosidase (Probe 2). This file may be easily imported into MS Excel, Gene- spring or other microarray analysis software to facilitate further analysis. Click here for file [http://www.biomedcentral.com/content/supplementary/1471- 2407-5-3-S1.txt] Acknowledgements The ∆N-β-catenin and β-galactosidase expression vectors, the Bosc23 cell line and the GAPDH probe were gifts of Drs. Hans Clevers, Trevor Dale, Maria Emanuela Cuomo and John Brown respectively. We thank Dr. Derek Radisky for a critical reading of the manuscript. This study was supported, in part, by a Ph.D. studentship from the Institute of Cancer Research. References 1. 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