Recent studies have shown that the microtubule disrupting protein Stathmin 1 (STMN1) is differentially expressed in AML patients and healthy control. The aim of this study was to explore the effects and molecular mechanism of STMN1 in AML. Here, the expression of STMN1 in peripheral blood cells (PBMCs) and bone marrow of AML patients and healthy volunteers was detected by RT-PCR and Western blot. STMN1 expression was regulated by transfected with STMN1 overexpressed plasmid or shRNA in two human leukemia cell lines K562 and HL60. Cell proliferation was examined by CCK8 and Edu staining. Annexin V and TUNEL assays were applied to test cell apoptosis. Flow cytometry was used to test the cell cycle distribution. The activation of the PI3K signaling pathway and the expression levels of cell cycle and cell apoptosis-related protein were determined by Western blot. In this study, we found that STMN1 was overexpressed in PBMCs and bone marrow of AML patients. STMN1 expression was closely related to FAB subtypes, risk stratification, disease-free survival, and overall survival of AML. Functional assays showed that overexpression of STMN1 in HL60 and K562 cells enhanced cell proliferation, decreased cell apoptosis, and caused G 1 phase arrest. In contrast, suppression of STMN1reduced cell proliferation and enhanced cell apoptosis in both HL60 and K562 cells. Moreover, the PI3K/Akt pathway was activated by STMN1, while suppression of STMN1 dysregulated the PI3K/Akt pathway and upregulating the levels of caspases3 and Bax expression. In conclusion, STMN1 was confirmed to promote the proliferation and inhibit the apoptosis of HL60 and K562 cells by modulating the PI3K/Akt pathway. STMN1 might be a novel molecular target for treating AML.

Recent studies have shown that the microtubule disrupting protein Stathmin 1 (STMN1) is differentially expressed in AML patients and healthy control. The aim of this study was to explore the effects and molecular mechanism of STMN1 in AML. Here, the expression of STMN1 in peripheral blood cells (PBMCs) and bone marrow of AML patients and healthy volunteers was detected by RT-PCR and Western blot. STMN1 expression was regulated by transfected with STMN1 overexpressed plasmid or shRNA in two human leukemia cell lines K562 and HL60. Cell proliferation was examined by CCK8 and Edu staining. Annexin V and TUNEL assays were applied to test cell apoptosis. Flow cytometry was used to test the cell cycle distribution. The activation of the PI3K signaling pathway and the expression levels of cell cycle and cell apoptosis-related protein were determined by Western blot. In this study, we found that STMN1 was overexpressed in PBMCs and bone marrow of AML patients. STMN1 expression was closely related to FAB subtypes, risk stratification, disease-free survival, and overall survival of AML. Functional assays showed that overexpression of STMN1 in HL60 and K562 cells enhanced cell proliferation, decreased cell apoptosis, and caused G 1 phase arrest. In contrast, suppression of STMN1reduced cell proliferation and enhanced cell apoptosis in both HL60 and K562 cells. Moreover, the PI3K/Akt pathway was activated by STMN1, while suppression of STMN1 dysregulated the PI3K/Akt pathway and upregulating the levels of caspases3 and Bax expression. In conclusion, STMN1 was confirmed to promote the proliferation and inhibit the apoptosis of HL60 and K562 cells by modulating the PI3K/Akt pathway. STMN1 might be a novel molecular target for treating AML.