Identification of LY6K target genes in bladder cancer

Five bladder cancer (BC) cell lines were subjected to high-resolution array comparative genomic hybridization (CGH), which contained about 244,000 probes. The focus was on the typical gain locus of 8q24.3, which has not been studied in detail for BC. Integrating array-CGH data with the results of gene-expression profiling using oligo-microarray analysis revealed that 34 genes on 8q24.3 were generally up-regulated in the cell lines. Among these 34 genes, lymphocyte antigen 6 complex locus K (LY6K), which is a cancer/testis antigen, was the most up-regulated one in the BC (13.76-fold) as well as in clinical BC samples (2.84-fold). Investigation molecular network of LY6K performed using another oligo-microarray of the LY6K transfectant demonstrated that 269 genes were generally up-regulated more than five-fold in the transfectant. Twenty-one percent of the up-regulated genes were annotated into ‘cell cycle’ category, suggesting that LY6K is a promising molecular target for BC. LY6K transfected cancer cells vs control cells