cDNA microarray analysis of a glucocorticoid treated acute lymphoblastic leukemia cell line

The objective of the present study was the analysis of microarray data from a T-cell leukemia cell line (CCRF-CEM), treated with two different prednisolone concentrations, using four different pre-processing methods, within the Matlab^reg computing environment. We have compared these methods using hierarchical clustering. The gene expression patterns revealed by hierarchical clustering were used to draw probable conclusions on the question whether resistance to glucocorticoids is inherent or acquired, in this type of cells. Although different algorithmic approaches have concluded different results, the set of genes examined manifested an opposing pattern in their expression profile between low and high prednisolone concentrations. This opposing behavior seems to be related to glucocorticoid receptor-related gene repression or activation, leading to the activation of resistance mechanisms within the cell system studied.