Histone deacetylase inhibitor LBH589 induces apoptosis of multiple myeloma cell line U266 in vitro and its mechanism

Abstract

Objective To study the effect of new generation histone deacetylase inhibitor LBH589 single-drug or combined with the mouse serum which contains the radix echinopsis on multiple myeloma (MM) cell line U266 and their mechanism. Methods The acetylation level of α-tublin which was a substrate of HDAC6 was detected by Western blot.The chemical force between Heat shock protein 90 (HSP90) and its client proteins was detected by immune precipitation (IP). Results The different concentrations of LBH589 single drug (0, 20, 50 nmol/L), and 50 nmol/L combined with the mouse serum which contained the radix echinopsis (1 g/ml) were able to inhibit the proliferation of U266 cell. With the increase of drug concentration and the extension of time, the acetylation levels of α-tublin and HSP90 increased gradually (at 24 or 48 hours) in a dose dependent (P < 0.05). The inhibition of LBH589 combined with the mouse serum was stronger than that of LBH589 single drug (P < 0.05). Conclusion LBH589 could inhibit the growth of MM cells and their cell cycles, and induce the apoptosis of MM cell line U266. Key words: Multiple myeloma; LBH589; Western blot; Immune precipitation; Heat shock protein 90; α-tubulin