Acute lymphoblastic leukemia (ALL) is usually a common hematological malignancy characterized by the uncontrolled proliferation of leukemia cells in children. breast malignancy , bladder cancer , prostate cancer  and mesothelioma . Butein has inhibited CXCR4 manifestation, which is usually correlated with the inhibition of SRT3190 CXCL12-induced migration and invasion in breast and pancreatic cancer cells . In addition, butein has been found to suppress proliferation, induce apoptosis and overcome gefitinib-resistance in lung cancer via EGFR/MET signaling pathway . Moreover, butein has inhibited the growth of xenografted human colorectal tumors and hepatocellular carcinoma in vivo [13, 14]. In addition to solid tumors, butein has been proved to prevent telomerase activity and proliferation, induce apoptosis and differentiation in leukemia cells through Akt/hTERT pathway . Furthermore, butein could reverse the TRAIL-resistance of human myeloid leukemia U937 cells . Although SRT3190 it has been shown that butein could suppress proliferation, induce apoptosis and differentiation in myeloid leukemia cells, its molecular mechanisms responsible for inhibition of cell growth and cell cycle progression in acute lymphoblastic leukemia are yet unknown. In this study, we investigated the effect of butein on cellular proliferation and cell cycle arrest in ALL cell lines and primary leukemic blasts from pediatric ALL. Additionally, we also identify the role of butein in the rules of the nuclear translocation of Forkhead Class box O3a (FOXO3a) and the p27kip1 signaling pathway in ALL cells. Our results indicate that butein would serve as a potential candidate targeting FOXO3a to promote p27kip1 manifestation for anti-leukemic treatment. RESULTS Butein inhibits the proliferation of ALL cells in a dose-dependent manner The molecular structure of butein was showed in Physique ?Figure1A.1A. To evaluate the effects of butein on the renal toxicity of human normal proximal tubular cell and the proliferation of ALL cells, we examined the viability of HK-2 cell line and ALL cells. As shown in Physique ?Figure1B1B and Figure ?Physique1C,1C, various concentrations of butein remarkably inhibited the proliferation of the ALL cell lines (RS4-11, CEM-C7, CEM-C1 and MOLT-4) in a concentration-dependent manner. Compared to ALL cell lines, different concentrations of butein didn’t amazingly prevent the viability of HK-2 cell. Physique 1 Butein inhibited the proliferation of SRT3190 ALL cells Butein suppresses the viability of ALL cells at different treatment occasions We also tested theinhibition of proliferation of ALL cells uncovered to 0, 25, 50 or 100 M butein for 24, 48, and 72 h. Butein significantly inhibited the viability and proliferation of RS4-11 (Physique ?(Figure2A),2A), CEM-C7 (Figure ?(Physique2W),2B), CEM-C1 (Physique ?(Figure2C)2C) and MOLT-4 (Figure ?(Figure2D)2D) cell lines at different treatment occasions. Physique 2 Butein inhibited the viability of ALL cells at different occasions Butein inhibits the growth of primary ALL cells ex lover vivo To examine the effect of butein on primary B-ALL blasts, T-ALL blasts and normal mononuclear cells, we analyzed the cell proliferation using the MTS assay. We uncovered these cells to 0, 25, 50, or 100 M butein for 24 h. As shown in Physique ?Determine3A,3A, the growth of B-ALL blasts was markedly inhibited in a dose-dependent manner. The comparable result was obtained in T-ALL blasts (Physique ?(Figure3B).3B). Oddly enough, treatment with butein resulted in the dose-dependent growth inhibition of primary ALL cells, but has no cytotoxicity in normal mononuclear cells at the same dose (Physique ?(Physique3C3C). Physique 3 Butein inhibited the proliferation of primary ALL blasts ex lover vivo Butein induces cell cycle arrest CALN in ALL cells We also analyzed the effects of.