Retinoic acid/alpha-interferon combination inhibits growth and promotes apoptosis in mantle cell lymphoma through Akt-dependent modulation of critical targets

Abstract

Mantle cell lymphoma (MCL) is characterized by a profound deregulation of the mechanisms controlling cell-cycle progression and survival. We herein show that the combination of 9-cis-retinoic acid (RA) and IFN-α induces marked antiproliferative and proapoptotic effects in MCL cells through the modulation of critical targets. Particularly, IFN-α enhances RA-mediated G 0-G 1 cell accumulation by downregulating cyclin D1 and increasing p27 Kip1 and p21 WAF1/Cip1 protein levels. Furthermore, RA/IFN-α combination also induces apoptosis by triggering both caspases-8 and -9 resulting in Bax and Bak activation. In particular, RA/IFN-α treatment downregulates the antiapoptotic Bcl-xL and Bfl-1 protei..