Expression analysis of genes located in the minimally deleted regions of 13q14 and 11q22-23 in chronic lymphocytic leukemia – unexpected expression pattern of the RHO GTPase activator ARHGAP20

In chronic lymphocytic leukemia (CLL), 13q14 and 11q22-23 deletions are found in 2/3 of the cases. 11q22-23 deletions are associated with poor survival, whereas 13q14 deletions as single abnormality are often found in indolent disease forms. The molecular basis for this difference in prognosis is not known. ARHGAP20 encodes an evolutionarily conserved protein. In the zebra fish (Danio rerio) genome the syntenic regions of human chromosomal bands 13q14 and 11q22-23 are juxtaposed. The similar expression profiles of ARHGAP20 in 13q14 and 11q22-23 deleted CLL cases suggest a molecular connection and an intriguing mechanism of regulation. Analysis of 154 samples of peripheral blood mononuclear cells (109 HGU-133plus2; 45 HGU-133A; 45 HGU-133B) from adult patients with chronic lymphocytic leukemia (CLL).