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BACKGROUNDIntegrin alpha2 beta1 (α2β1) plays an integral role in tumour cell invasion, metastasis and angiogenesis, and altered expression of the receptor has been linked to tumour prognosis in several solid tumours. However, the relationship is complex, with both increased and decreased expression associated with different stages of tumour metastases in several tumour types. The ITGA2 gene, which codes for the α2 subunit, was examined to investigate whether a large CpG island associated with its promoter region is involved in the differential expression of ITGA2 observed in prostate cancer.METHODSBisulphite sequencing of the ITGA2 promoter was used to assess methylation in formalin-fixed paraffin-embedded (FFPE) prostate tumour specimens and prostate cancer cell lines, PC3, 22Rv1 and LNCaP. Changes in ITGA2 mRNA expression were measured using quantitative PCR. ITGA2 functionality was interrogated using cell migration scratch assays and siRNA knockdown experiments.RESULTSBisulphite sequencing revealed strikingly decreased methylation at key CpG sites within the promoter of tumour samples, when compared with normal prostate tissue. Altered methylation of this CpG island is also associated with differences in expression in the non-invasive LNCaP, and the highly metastatic PC3 and 22Rv1 prostate cancer cell lines. Further bisulphite sequencing confirmed that selected CpGs were highly methylated in LNCaP cells, whilst only low levels of methylation were observed in PC3 and 22Rv1 cells, correlating with ITGA2 transcript levels. Examination of the increased expression of ITGA2 was shown to influence migratory potential via scratch assay in PC3, 22Rv1 and LNCaP cells, and was confirmed by siRNA knockdown experiments.CONCLUSIONSTaken together, our data supports the assertion that epigenetic modification of the ITGA2 promoter is a mechanism by which ITGA2 expression is regulated.

This document contains briefing charts on the program. This briefing presents the RDCS (Robust Design Computational System). The purpose of this effort is to utilize an RDCS driven feature based parametric processing model for producibility assessments through the web based front end of the producibility model. The objectives are to illustrate parameterization of process module, show current stage of module development, highlight integration issues and direction of work and demonstrate feature based parametrized producibility assessment. The approach taken will parameterize geometry inputs to processing module based on use scenario for a producibility assessment., The original document contains color images. Prepared in cooperation with Convergent Manufacturing Technologies and Northrop Grumman. Presented at the International SAMPE Technical Conference (34th) held in Baltimore MD on 4-7 November 2002.