[Down-regulation of HDAC6 Expression Promotes Apoptosis of Human Leukemia K562 Cells].

Objective: To study the promoting-apoptosis effect of HDAC6 on the human leukemia cells and its mechanism.

Methods: The siRNA interference technology was used to inhibit the expression of HDAC6 gene, the RT-PCR and Western blot were used to detect the expression of HDAC6 and related signal pathway proteins respectively, the flow cytometry and Hoechest staining were used to detect the apoptosis and morphology changes of K562 cells.

Results: Compared with the periphal blood monocyte and bone marrow stromal cells of healthy volunteers, the expression level of HDAC6 in leukemia cell lines was up-regulated significantly(P<0.05); the flow cytometry and Hoechest staining showed that after interference of HDAC6 gene, the apoptosis of K562 cells increased, moreover the cell morphology was changed; the Western blot detection showed that the interfering HDAC6 increased BAX/BCL-2 ratio and cleaved caspase 3 expression, and activated the MAPK, ATK, ERK signaling pathway.

Conclusion: The interferance of HDAC6 can promote the K562 cell apoptosis, its mechanism may relate with activation of MAPK signaling pathway.