Submitted September 17, 2007
Accepted December 31, 2007
The aiolos transcription factor is up-regulated in chronic lymphocytic leukemia
Marianne Duhamel, Issam Arrouss, Helene Merle-Beral, and Angelita Rebollo*
Immunologie Cellulaire et Tissulaire, Inserm U543 and Universite Pierre et Marie Curie, Hopital Pitie-Salpetriere, Paris, France
Service d'Hematologie Biologique, AP-HP, Universite Pierre et Marie Curie Paris VI INSERM U453, Hopital Pitie-Salpetriere, Paris, France
* Corresponding author; email: rebollo{at}chups.jussieu.fr.
The Aiolos transcription factor, member of the Ikaros family of zinc-finger proteins, plays an important role in the control of mature B lymphocyte differentiation and proliferation and its function appears to be modulated through alternative splicing. In order to assess Aiolos isoform role in humans’ pathologies, we studied Aiolos variant distribution and expression in mature B lymphoproliferative disorders (chronic lymphocytic leukemia and other B-cell lymphomas). We demonstrated that over 80% of expressed Aiolos in normal as well as in malignant B cells is of the hAio1 type and we showed for the first time a homogeneous overexpression of the total amounts of Aiolos transcripts in the B cells of CLL patients, independently of ZAP-70 and IgVH mutational status prognosis factors. This up-regulation of Aiolos, confirmed at protein level, seems independent of Aiolos promoter H3K9 acetylation and H3K4 trimethylation.
