Cross platform microarray analysis. The figure shows ratios (log2 based) from 553 genes comparable between the cDNA and the Illumina platforms. Red dots: genes significantly up-regulated on the Illumina platform. Green dots: genes significantly down-regulated on the Illumina platform. Black dots: genes not identified as significantly different between the cell lines (AR42J versus NRK52E) on the Illumina platform. All the genes were identified as differentially expressed on the cDNA platform, and the concordance between cDNA and Illumia is 72 %.