Abstract
Objectives: To explore the effects of 13-cis-retinoic acid (13cRA) alone or combined with interferonα-2b (IFNα-2b) for the inhibition of cell growth and apoptosis induction of mantle cell lymphoma cell lines Jeko-1 cells. Methods: Jeko-1 cells were treated by different concentrations of 13cRA alone or combined with IFN-α2b. CCK-8 was used to measure the inhibition effects by different treatments. Cell cycles were analyzed by flow cytometry. Effects on apoptosis were assessed by staining of Annexin Ⅴ/PI. And the levels of Cyclin D1, caspase-9 and Rb proteins were measured by Western blot method. Results: 13cRA alone at different doses and its combination with IFNα-2b inhibited Jeko-1 cells growth and induced apoptosis, but the combination had higher inhibition potential and significant apoptosis rate (P<0.05) . The growth inhibition and apoptosis induction in Jeko-1 cells increased significantly with the elevation of drugs concentration and treating duration (P<0.05) . As well as the percentage of Jeko-1 cells at G(1)/G(2) phases increased (P<0.05) and cells at S phase decreased (P<0.05) , the levels of Cyclin D1 and Rb decreased with elimination caspase-9. Conclusion: 13cRA, IFN-α2b and their combined administration inhibited cells growth and induced apoptosis, decreased the cell populations at S phase and blocked the cells at G(1)/G(2) phase. Combination of the drugs may have a cooperated action. The therapeutic synergistic effects of 13cRA and IFN-α2b were assumed to lower the expression of Cyclin D1 and Rb proteins, and induce apoptosis by activating caspase-9 pathway.