OBJECTIVETo observe the status of AKT and phospho-AKT (pAKT) in three diffuse large B cell lymphoma (DLBCL) cell lines, and to investigate the effects of AKT activation on biologic behavior of DLBCL cells.

METHODSThree DLBCL cell lines, ly1, ly8 and ly10 were maintained in 10% FBS or serum free culture medium. The expression of AKT and status of pAKT were detected by Western blotting. LY294002, an inhibitor of PI3K, was used to suppress the level of pAKT. Flow cytometry combined with PI staining, AnnexinV-FITC assay and Brdu incorporation assay were used to analyze the parameters of the cell cycle, apoptosis and proliferation respectively.

RESULTSThere was constitutive activation of AKT in three DLBCL cell lines and the levels of pAKT were altered in the different environments. In 10% FBS culture medium, pAKT was higher than that in serum free culture medium in ly8 and ly10, however, pAKT in ly1 maintained in serum free culture medium was mildly higher than that in 10% FBS culture medium. When the cell lines ly1, ly8, ly10 were maintained in 10% FBS culture medium, the inhibitor LY294002 suppressed the level of pAKT efficiently in three DLBCL cell lines. The percentage of cells at S phase and the proliferation index were significantly decreased (P < 0.05) without an increase of apoptosis (P > 0.05).

CONCLUSIONSActivation of AKT may play an important role in the development of DLBCL. It is closely related to the control of cell cycle and proliferation, but is not associated with apoptosis. LY294002 can inhibit cell growth by decreasing the levels of pAKT in DLBCL cell lines.