Gene expression profile for ATO-induced changes in the Bcl-2 family. U266, MM.1s, 8226/S, and KMS11 cell lines were treated with 2 μM ATO for 6, 24, and 48 hours. Total RNA was obtained and cRNA was probed on Affymetrix Hu133 2.0 Plus Chips. Signal intensity was used as gene expression. Ratios at 6, 24, and 48 hours versus baseline gene expression were calculated for each probe set and average ratios were obtained for genes. Bcl-2 family member genes were clustered using the bioinformatic programs Cluster and TreeView. The bar at the bottom represents the scale for fold changes.