Down-regulation of HDAC6 Expression Can Influence KG1α Cell Proliferation by Inhibiting ERK Pathway / 中国实验血液学杂志

OBJECTIVE@#To study the inhibitory effect of HDAC6 on proliferation of human leukemia KG1α and to explore its mechanism by ERK signaling pathways.@*METHODS@#.The siRNA interference technology was used to inhibit the HDAC6 gene expression; the expression of HDAC6 and prateins of ERK signal pathway was detected by Western blot; the cell proliferation ability was detected by colony forming experiment and trypan blue staining; cell cycle was detected by FCM; and the expression of Ki67 was detected by immunofluorescence.@*RESULTS@#Western blot showed that HDAC6 expression was up-regulated in leukemia cell lines in comparison with the healthy volunteers and bone marrow stromal cells (P＜0.05). Knockdown of HDAC6 significantly inhibited the proliferation and colony formation ability of leukemia cells, promoted cell arrest at G/G phase. The Western blot and immunefluorescence showed that knockdown of HDAC6 suppressed the expression level of Ki67, CDK4, Cyclin D1 and enhanced the expression level of p16, p21, p-ERK (P＜0.05).@*CONCLUSION@#Knockdown of HDAC6 significantly inhibits the proliferation, arrest the cell cycle at G/G phase, and its mechanism probably relates with the activation of ERK signaling pathway.

Down-regulation of HDAC6 Expression Promotes Apoptosis of Human Leukemia K562 Cells / 中国实验血液学杂志

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.