Sfrps Family Invovled in Growth Inhibition of K562 Cells Induced by Artesunate

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 5015-5015
Author(s):  
Wang Ying ◽  
Guo xiao Nan ◽  
Zhang xue Jun ◽  
Ren jin Hai ◽  
Qiao shu Kai ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Research Funding ◽  
Wnt Pathway ◽  
K562 Cells ◽  
Hebei Province ◽  
Control Group ◽  
Dependent Manner ◽  
Inhibition Rate ◽  
Concentration Dependent Manner ◽  
Expression Levels

Abstract Abstract 5015 Introduction: Studies have shown that abnormal activation of wnt signaling pathway is closely related to tumor genesis. Cell surface coil protein (frizzled, fzd) is a specific receptor for wnt pathway to activate its downstream signaling through β-catenin to stimulate the growth of a range of tumor cells. Secreted frizzled related proteins (sfrps) are the main antagonists of wnt pathway. sfrps can inhibit the function of wnt pathway via competing with fzd receptor. Recent studies have found that sfrps family memberes expressed at very low levels in a variety of tumor cells,which was closely related to the methylation of sfrps gene promoters. DNA methyltransferase (dnmts) are the key enzymes involved in DNA methylation, which can promote the methylation of tumor suppressor genes' promoters and inhibit transcription of these genes, and induce tumor genesis. Artesunate, a semi-synthetic derivative of artemisinin, is very effective in antimalaria. Recent studies have shown that artesunate has anti-tumor functions. However, the effect of artesunate on the expression of sfrps- and dnmts- mRNAs and β-catenin protein are not clear. To evaluate the growth inhibition effect of Artesunate (at final concentrations of 0μg/ml, 4μg/ml, 10μg/ml, 20μg/ml and 40μg/ml) on K562 cells and to investigate its potential mechanism by detecting the expression levels of sfrps- and dnmts- mRNAs and β-catenin protein in K562 cells treated with artesunate. Methods: Cell growth inhibition rate and cell cycle distribution of K562 cells induced by artesunate treatment were measured by MTT assay and flow cytometry, respectively. The mRNA expression levels of sfrp1, sfrp2, sfrp4 and dnmt1, dnmt3a, dnmt3b in K562 cells which had been treated with or without artesunate for 48 hours were evaluated with reverse transcription-polymerase chain reaction (RT-PCR). Protein expression level of β-catenin in K562 cells were detected by Western blot. Results: Artesunate treatment significantly induced growth inhibition of K562 cells in a concentration-dependent manner after the cells were treated with artesunate for 48 hours(p < 0.05). The inhibition rate of 4,10,20 and 40(μg/ml)artesunate exposure were 54.29%, 58.03%, 69.33% and 77.98% respectively. Flow cytometry analysis showed that K562 cells were arrested at G0/Gl and G2/M phase in concentration-dependent manner after 48 hours exposure of artesunate (p < 0.05). After treated with artesunate at the final concentrations of 0, 4, 10, 20 and 40μg/ml, the relative expression levels of sfrp1, sfrp2 and sfrp4 mRNA in K562 cells increased, while the expression levels of dnmtl, dnmt3a, dnmt3b mRNA decreased significantly compared with the control group. Results from Western blot showed that β-catenin protein levels decreased in a concentration-dependent manner, when compared with that of the control group (P<0.05). Conclusion: Results from the present study indicated that artesunate could inhibite the mRNA expression of dnmts family and minimize the methylation of sfrps gene promoter. Therefore, sfrps could inhibit the function of wnt pathway through competing with fzd receptors. Meanwhile, artesunate could decrease the expression of β-catenin protein in K562 cells, and could further inhibit the function of wnt pathway. Therefore, data from the present experiment provides a new theoretical basis for clinical application of artesunate in leukemia treatment. Disclosures: Ying: Nature science foundation of Hebei Province: Research Funding. Nan:Nature science foundation of Hebei Province: Research Funding. Jun:Nature science foundation of Hebei Province: Research Funding. Hai:Nature science foundation of Hebei Province: Research Funding. Kai:Nature science foundation of Hebei Province: Research Funding. Xu:Nature science foundation of Hebei Province: Research Funding. Pan:Nature science foundation of Hebei Province: Research Funding.

scholarly journals Inhibitory Effect of Centipede Scolopendra Extract on Gallbladder Carcinoma via Up-regulation of PUMA

2021 ◽  
Author(s):  
Cheng Yan ◽  
Yangyan Xiao ◽  
Jingfen Ji ◽  
Zhide Liu ◽  
Weichang Zhang ◽  
...  
Keyword(s):  
Cell Line ◽  
Western Blotting ◽  
Gallbladder Carcinoma ◽  
Colony Formation ◽  
Control Group ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Expression Levels ◽  
Apoptosis Rate ◽  
Sirna Group

Abstract Background: To observe the effect of centipede scolopendra extract on gallbladder carcinoma (GBC) and further investigate its underlying mechanism.Methods: The GBC cell line GBC-SD was purchased and cultured. Small interfering RNA (siRNA) was constructed. The mRNA expression levels of PUMA were measured by reverse transcription-quantitative PCR (RT-qPCR) and protein expression levels of p53, PUMA, Bax and Bcl-2 were measured by western blotting respectively. Viability and proliferation were detected using MTT and colony formation assays respectively. The apoptosis rate was determined by Annexin-V-FITC/PI double staining. Results: The GBC-SD cell line was successfully obtained and cultured. MTT and colony formation assays demonstrated that the viability and proliferation of GBC-SD cells could be markedly inhibited by centipede scolopendra extract in a concentration-dependent manner in the limited concentration range. Following pretreatment with centipede scolopendra extract, RT-qPCR demonstrated that the expression levels of PUMA were markedly increased in the GBC-SD cells, and western blotting showed that the high expression of PUMA was accompanied by upregulation of Bax and downregulation of p53 and Bcl-2 in the GBC-SD cells. However, this effect has proved hard to reproduce after PUMA-siRNA. Flow cytometry revealed that the apoptosis rate was 9.8±2.2%, 25.3±3.6%, 10.6±2.0%, and 13.5±2.4% in control group, centipede scolopendra extract group, PUMA-siRNA group, and centipede scolopendra extract combined with PUMA-siRNA group respectively. Conclusions: Centipede scolopendra extract could induce the apoptosis of GBC-SD cells by promoting the PUMA-Bax signaling pathway. It could serve as a potential novel therapy for GBC in clinical practice.

Synthesis and anticancer evaluation of sulfur containing 9-anilinoacridines

2021 ◽  
Vol 16 ◽  
Author(s):  
Pranav Gupta ◽  
Radhika V. Kumar ◽  
Chul-Hoon Kwon ◽  
Zhe-Sheng Chen
Keyword(s):  
Cell Cycle ◽  
Anticancer Activity ◽  
Topoisomerase Ii ◽  
Critical Role ◽  
K562 Cells ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
In Vivo Models ◽  
Topo Ii ◽  
Sulfur Containing

Background: DNA topoisomerases are a class of enzymes that play a critical role in fundamental biological processes of replication, transcription, recombination, repair and chromatin remodeling. Amsacrine (m-AMSA), the best-known compound of 9-anilinoacridines series was one of the first DNA-intercalating agents to be considered as a Topoisomerase II inhibitor. Objective: A series of sulfur containing 9-anilinoacridines related to amsacrine were synthesized and evaluated for their anticancer activity. Methods: Cell viability was assessed by the MTT assay. The topoisomerase II inhibitory assay was performed using the Human topoisomerase II Assay kit and flow cytometry was used to evaluate the effects on cell cycle of K562 cells. Molecular docking was performed using Schrödinger Maestro program. Results: Compound 36 was found to be the most cytotoxic of the sulfide series against SW620, K562, and MCF-7. The limited SAR suggested the importance of the methansulfonamidoacetamide side chain functionality, the lipophilicity and relative metabolic stability of 36 in contributing to the cytotoxicity. Topoisomerase II α inhibitory activity appeared to be involved in the cytotoxicity of 36 through inhibition of decatenation of kinetoplast DNA (kDNA) in a concentration dependent manner. Cell cycle analysis further showed the Topo II inhibition through accumulation of K562 cells in G2/M phase of cell cycle. Docking of 36 into the Topo II α-DNA complex suggested that it may be an allosteric inhibitor of Topo II α. Conclusion: Compound 36 exhibits anticancer activity by inhibiting topoisomerase II and it could further be evaluated in in vivo models.

scholarly journals Ca2+ signalling in K562 human erythroleukaemia cells: effect of dimethyl sulphoxide and role of G-proteins in thrombin- and thromboxane A2-activated pathways

1995 ◽  
Vol 312 (1) ◽  
pp. 151-158 ◽  
Author(s):  
C P Thomas ◽  
M J Dunn ◽  
R Mattera
Keyword(s):  
G Proteins ◽  
Pcr Amplification ◽  
Thromboxane A2 ◽  
K562 Cells ◽  
Protein S ◽  
Term Treatment ◽  
Dependent Manner ◽  
Short Term Treatment ◽  
Concentration Dependent Manner ◽  
Prostaglandin F2 Alpha

The human leukaemic cell line K562 is a pluripotent stem cell with the potential to mature along a megakaryocytic or erythroid line. In these cells, thrombin and U46619 (9,11-dideoxy-9 alpha, 11 alpha-methanoepoxy prostaglandin F2 alpha), a thromboxane A2 analogue, increased intracellular Ca2+ in a rapid and concentration-dependent manner. The peak transient observed with both thrombin and U46619 was preserved upon stimulation in the absence of extracellular calcium and blunted with phorbol myristate acetate, suggestive of activation of phospholipase C. Short-term treatment with leupeptin abolished the calcium response to thrombin, but did not alter that to U46619. Both pertussis toxin (PT) and DMSO pretreatment inhibited thrombin- but not U46619-stimulated intracellular calcium elevation, indicating that these agonists signal through different G-proteins. Western blot analysis of crude membranes from K562 cells revealed the presence of G12 alpha and G13 alpha; the other known PT-substrates, Gi1 alpha and G0 alpha, were not detected. Consistent with this observation, ADP-ribosylation experiments revealed the presence of two PT substrates which co-migrated with human erythrocyte G12 alpha and G13 alpha. An antibody raised against Gq/11 alpha, a subfamily of G-protein alpha subunits unmodified by PT, specifically recognized 42 kDa protein(s) in K562 cells. PCR amplification of reverse-transcribed K562 RNA followed by DNA sequencing showed that these cells express messages for both Gq alpha and G11 alpha. Treatment of K562 cells with DMSO reduced the levels of thrombin receptor mRNA, without simultaneous changes in the expression of G12 alpha and G13 alpha. We have thus identified Ca(2+)-mobilizing agonists and related G-proteins in K562 cells, together with changes induced by DMSO in this signalling pathway.

scholarly journals Sequestration of erythrocytes infected with Plasmodium berghei ANKA in BALB/c mice treated with goat bile

2020 ◽  
Vol 4 (2) ◽  
pp. 179
Author(s):  
Kartika Arum Wardani ◽  
Kholida Nur Aini ◽  
Heny Arwati ◽  
Willy Sandhika
Keyword(s):  
Plasmodium Berghei ◽  
Antimalarial Activity ◽  
Negative Control ◽  
Control Group ◽  
Dependent Manner ◽  
Plasmodium Berghei Anka ◽  
Concentration Dependent Manner ◽  
Control Group Design ◽  
Bile Concentration

Abstract Sequestration of Plasmodium berghei ANKA-infected erythrocytes occurs in BALB/c mice as characteristic of  Plasmodium falciparum infection in humans. Animals’ bile has been widely used for centuries in Traditional Chinese Medicine. Goat bile has been used in healing infectious and non-infectious diseases; however, no report on the use of goat bile against malaria infection and sequestration. The purpose of this study was to analyze the correlation between parasitemia and sequestration in the liver of P.berghei ANKA-infected BALB/c mice treated with goat bile. This research was an in vivo experimental study using the post-test control group design. The male BALB/c mice aged ± 6 weeks, body weight 20-25 g were used. The mice were divided into five groups where Group 1-3 were mice treated with goat bile 25%, 50%, and 100%, respectively. Group 4-5 were negative (sterile water) and positive controls (DHP). Parasitemia was observed daily from each mouse and the number of sequestered infected erythrocytes on the endothelium of sinusoids. The data were analyzed using t independent test. Antimalarial activity of goat bile was shown by the lower parasitemia in goat bile-treated mice compared with the negative control. The average number of sequestration was goat bile concentration-dependent manner. The higher the concentration, the lower the number of sequestration. Sequestration was correlated with parasitemia (p=0,0001). Sequestration of P.berghei ANKA-infected erythrocytes correlated with parasitemia, and was goat bile concentration-dependent manner. Keywords: Malaria, parasitemia, sequestration, goat bileCorrespondence: [email protected]

scholarly journals Relaxant effect of quercetin on rabbit isolated bladder smooth muscles contractions

2020 ◽  
Vol 10 (1) ◽  
pp. 61-67
Author(s):  
Hassan Sadraei ◽  
Sabihe Tabesh
Keyword(s):  
Smooth Muscles ◽  
Electrical Field Stimulation ◽  
Negative Control ◽  
Flavonoid Compound ◽  
Drug Candidate ◽  
Control Group ◽  
Organ Bath ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Relaxant Effect

Introduction: Quercetin is a flavonoid compound found in many medicinal plants. Antispasmodic effect of quercetin has been reported in ileum and uterus smooth muscles but not in bladder. Therefore, the objective of this research was to investigate relaxant effect of quercetin in rabbit isolated bladder. Methods: Male rabbit was asphyxiated with carbon dioxide and then sacrificed. The whole bladder was dissected out and placed in oxygenated Tyrode’s solution. Isolated bladder was cut into longitudinal strips and placed in an organ bath for contraction studies. Contractions were induced with KCl (20mM), acetylcholine (5μM) and electrical field stimulation (EFS). Full inhibitory concentration–response curve was constructed for quercetin following addition of above spasmogens. Quercetin was added into the organ bath with 2 fold increments in concentration until maximum response was achieved. Nifedipine was used as positive control group and equivalent volume of quercetin vehicle (water + DMSO) was used as negative control group.Results: Quercetin (4 μg/mL to 640 μg/mL) in a concentration dependent manner inhibited isolated bladder strips contracted by KCl (IC50=159±25 μg/mL), acetylcholine (IC50=43±9.1 μg/mL) and EFS (IC50=38±9.3 μg/mL). In the highest used concentration, quercetin completely removed contractile responses to KCl, acetylcholine and electrical filed stimulation (EFS). Nifedipine totally inhibited KCl response (IC50=115±36 ng/mL) but only partially inhibited acetylcholine and EFS responses. Conclusion: These results confirm the relaxant effect of quercetin on rabbit bladder and if similar effects are seen in human studies, then quercetin would be a suitable drug candidate to be investigated for bladder incontinence.

ATI-2341 Trifluoroacetic Acid (TFA) Promotes Menstrual Blood-Derived Mesenchymal Stem Cell Recruitment and Enhances Uterine Repair Through Gi Pathway in Asherman’s Syndrome

2022 ◽  
Vol 12 (3) ◽  
pp. 506-513
Author(s):  
Ying Lv ◽  
Liyan Ye ◽  
Xiujuan Zheng
Keyword(s):  
Menstrual Blood ◽  
Control Group ◽  
Dependent Manner ◽  
Asherman’S Syndrome ◽  
Expression Levels ◽  
Endometrial Cells ◽  
Injury Model ◽  
Recruitment Effect ◽  
Dose Dependent

This study aimed to explore the role of ATI-2341 in Asherman’s syndrome and its impact on menstrual blood-derived mesenchymal stem cells (MenSCs). Following establishment of endometrial injury model, MenSCs were extracted from rats and cultured. They were treated with ATI-2341 TFA at different concentrations (10 ng/mL, 50 ng/mL, 100 ng/mL) and MenSCs treated without ATI-2341 TFA were taken as controls. Flow cytometry was conducted to detect the cell cycle. MTT was carried out to evaluate proliferation of endometrial cells. The expression levels of MMP-9, TIMP-1, CK, and VIM were determined with staining used to reflect morphology of endometrium. Administration with ATI-2341 TFA resulted in decreased expression of MMP-9 and increased expression of TIMP-1 in a dose-dependent manner. Of note, the increase of ATI-2341 TFA concentration was accompanied with elevated cell proliferation rate, increased number of glands in the endometrium, and decreased fibrosis area. As treated with 100 ng/mL ATI-2341 TFA, the cells exhibited more glands than that under other concentrations with uniformly arranged glands and lowest expression levels of CK and VIM, control group had plenty of blue-stained collagen fibers in the intima and least amount of glands. ATI-2341 TFA 100 ng/mL induced endometrial epithelial recruitment effect on MenSCs and promoted endometrial repair more significantly than Gi-3 pathway agonists. Collectively, ATI-2341 TFA enhances MenSC recruitment and facilitates endometrial epithelial cells proliferation and the repair of uterine damage in Asherman’s syndrome through Gi pathway. These findings provide a\ novel insight into the MenSC-based treatment against Asherman’s syndrome and deserve further investigation.

scholarly journals Protective Effect of Silymarin against Rapamycin-induced Apoptosis and Proliferation Inhibition in Endothelial Progenitor Cells

2015 ◽  
Vol 10 (2) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Peng Zhang ◽  
Guohua Han ◽  
Pei Gao ◽  
Kun Qiao ◽  
Yusheng Ren ◽  
...  
Keyword(s):  
Progenitor Cells ◽  
Endothelial Progenitor Cells ◽  
Mononuclear Cells ◽  
Control Group ◽  
Dependent Manner ◽  
Endothelial Progenitor ◽  
Concentration Dependent Manner ◽  
Inhibition Of Proliferation ◽  
And Migration ◽  
Proliferation And Migration

For this study, peripheral blood samples were collected from human volunteers. Mononuclear cells (MNC) were separated by density centrifugation and were induced to differentiate into endothelial progenitor cells (EPCs) in vitro. Different concentrations of rapamycin and silymarin were introduced to the EPCs over 24 hours and then EPCs were analyzed for proliferation, migration, apoptosis and angiogenesis. Compared with the control group, rapamycin (1, 10, 100 ng/mL) inhibited the proliferation and migration of EPCs in a concentration dependent manner ( P<0.05). Silymarin (50, 100 μg/mL) enhanced the proliferation and migration of EPCs and inhibited apoptosis in a concentration dependent manner ( P<0.05). By adding rapamycin (1 ng/mL) and silymarin (25, 50, 100 μg/mL) over 24 hours, silymarin inhibited the pro-apoptotic effect of rapamycin on EPCs, and reversed the inhibition of proliferation, migration and angiogenesis of EPCs by rapamycin ( P<0.05).

Targeting Proteinkinase C Alters ER-Stress and b-Catenin Signaling in Multiple Myeloma: Therapeutic Implications.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 258-258
Author(s):  
Marc S. Raab ◽  
Klaus Podar ◽  
Jing Zhang ◽  
Giovanni Tonon ◽  
Johannes H. Fruehauf ◽  
...  
Keyword(s):  
Cell Death ◽  
Stress Response ◽  
Growth Inhibition ◽  
Er Stress ◽  
Cell Lines ◽  
Wnt Pathway ◽  
Dependent Manner ◽  
P53 Family ◽  
Er Stress Response

Abstract We have previously shown that the novel orally available small molecule inhibitor of PKC enzastaurin (Eli Lilly and Company) inhibits MM cell growth, survival and angiogenesis both in vitro and in vivo. To date, however, the downstream effects contributing to growth inhibition and cell death remain to be determined. Here, we performed global gene expression profiling on enzastaurin treated MM cells and identified 200 Genes to be differentially regulated with a &gt; 2-fold cut off. Strikingly, two major groups of up-regulated probe sets were associated with either of two pathways - endoplasmatic reticulum (ER)-stress response or WNT-signaling. Importantly, MM cells, producing high levels of paraprotein, are highly susceptible to perturbation of ER function and protein folding. Moreover, PKC isoforms have been reported to directly regulate the canonical WNT pathway via phosphorylation of b-catenin (CAT), leading to its ubiquination and proteasomal degradation. Specifically, we fist evaluated the role of enzastaurin in mediating ER-stress in MM cells. The transcriptional up-regulation of genes involved in ER-stress (GADD153/CHOP, GADD34, ATF3), triggered by enzastaurin at 3h, was confirmed by western blot analysis, accompanied by induction of the molecular ER chaperone BiP/grp78, phosphorylation of eIF2a consistent with PERK activation, and up-regulation of p21. These events were preceded by an early (1h) increase of intracellular calcium levels, a hallmark of ER-stress, assessed by FLUO4 staining. These data suggest an important role of ER-stress response in the early growth inhibition of MM cells caused by enzastaurin. Second, we delineated effects of enzastaurin on WNT pathway in MM and other tumor cell lines. Upon enzastaurin treatment, CAT was dephosphorylated at Ser33, 37, 41 in a dose- and time-dependent manner in all cell lines tested (10 MM, 3 colon cancer, HeLa, as well as human embryonic kidney 293 cells). Consequently, accumulation of CAT occurred in both cytosolic and nuclear fractions of treated MM cells, associated with activated TOPflash LUC-reporter system, confirming nuclear transactivating activity. Specific inhibition of CAT by siRNA partially rescued HeLa, HEK 293, and MM cells from cell death induced by enzastaurin. Analysis of downstream target molecules revealed a CAT-dependent up-regulation of c-Jun, but not of c-Myc or Cyclin D1. c-Jun has been reported to stabilize p73, a pro-apoptotic p53-family member; CAT induction by enzastaurin led to p73 (but not p53) activation and was also abrogated by CAT-specific siRNA. In turn, specific knockdown of p73 by siRNA rescued cells from enzastaurin-induced apoptosis. Finally, ectopic overexpression of CAT in HeLa and MM cells induced c-Jun expression and p73 activation, followed by apoptotic cell death. Our studies therefore indicate that ER-stress response contributes to the immediate inhibition of proliferation by enzastaurin, followed by CAT accumulation leading to p73 activation, contributing to enzastaurin-mediated cell death. These findings provide a novel link between CAT and p53-family members. Moreover p73, which is only rarely mutated in human cancers, represents a novel therapeutic target in MM.

PTEN Regulates VEGF, VEGFR1 Expression and Its Clinical Significance in Myeloid Leukemia.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1001-1001
Author(s):  
Zhiyong Cheng ◽  
Lin Pan ◽  
Xiaoling Guo ◽  
Xuejun Zhang ◽  
Fuxu Wang
Keyword(s):  
Clinical Significance ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
K562 Cells ◽  
Hebei Province ◽  
High Expression ◽  
Pten Gene ◽  
Wild Type ◽  
Akt Phosphorylation ◽  
Pten Mrna

Abstract Abstract 1001 Poster Board I-23 Phosphatase and tensin homology deleted on chromosome ten (PTEN) as a novel tumor suppressor gene, plays an important role in regulating proliferation, apoptosis, invasion and migration of many cancer cells. PTEN also modulates angiogenesis mediated by vascular endothelial growth factor (VEGF) via down-regulating the activity of PI3K/Akt pathway in many solid tumors. However, in myeloid leukemia, the effects of PTEN on VEGF and VEGFR1 (FLT1) mediated angiogenesis, migration, invasion of leukemia cells and its clinical significance are still unknown. Therefore, in the present study, we investigated the effect of PTEN on the activity of PI3K/Akt and VEGF/FLT1 pathways. Wild type PTEN gene was transfected into K562 cells, a cell line establish from a chronic myelogenous leukemia in blast crisis, to induce high expression of wild-type PTEN gene and protein by the cells. The correlation between the expression levels of PTEN and VEGF/FLT1 and its clinical significance in myeloid leukemia patients were also observed. We found that the expression reconstitution of wild-type PTEN had significance effect on inhibiting proliferation, migration and invasion ability of K562 cells via down-regulation of Akt phosphorylation and inhibition of VEGF/FLT1 expression. In myeloid leukemia patients, a negative correlation was found between the expression level of PTEN mRNA and that of VEGF and FLT1 mRNA. Low expression of PTEN mRNA and high expression of VEGF and FLT1 mRNA indicated a higher tendency of extramedullary disease in acute myeloid leukemia patients. Taken together, our findings indicated that PTEN could modulate the function of VEGF/VEGFR signaling pathway via down regulating Akt phosphorylation and that PTEN would be a candidate target for the treatment of myeloid leukemia. Disclosures: Pan: Nature science foundation of Hebei Province: Research Funding; Research Fund for the Doctoral Program of Higher Education of China: Research Funding; Emphases follow up pregram of Health Bureau of Hebei Province: Research Funding.

Activity of the Aurora Kinase Inhibitor, MLN8237 (alisertib) Alone or in Combination with Ponatinib Against Imatinib-Resistant BCR-ABL-Positive Cells

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1333-1333
Author(s):  
Seiichi Okabe ◽  
Tetsuzo Tauchi ◽  
Seiichiro Katagiri ◽  
Yuko Tanaka ◽  
Kazuma Ohyashiki
Keyword(s):  
Cell Cycle ◽  
Cell Growth ◽  
Growth Inhibition ◽  
Kinase Inhibitor ◽  
K562 Cells ◽  
Aurora Kinase ◽  
Dependent Manner ◽  
Cell Growth Inhibition ◽  
Cycle Arrest ◽  
T315i Mutation

Abstract Abstract 1333 Chronic myeloid leukemia (CML) is characterized by cytogenetic aberration (Philadelphia chromosome: Ph) and chimeric tyrosine kinase BCR-ABL. ABL tyrosine kinase inhibitor, imatinib has demonstrated the potency against CML patients. However, resistance to imatinib can develop in CML patients due to BCR-ABL point mutations. One of T315I mutation is resistant to currently available ABL tyrosine kinase inhibitors. Therefore, new approach against T315I mutant may improve the outcome of Ph-positive leukemia patients. Aurora kinases are serine/threonine kinases and upregulated in many malignancies including leukemia, and play an important role in cell cycle control and tumor proliferations. Because Aurora kinases are overexpressed in leukemia cells, Aurora kinases may present attractive targets for leukemia treatment. One of Aurora kinase inhibitor, MLN8237 (alisertib) is an oral and selective Aurora kinase A inhibitor and is currently being investigated in a pivotal phase 3 clinical trial against hematological malignancies. We suggested that alisertib mediated inhibition Aurora kinase activity and in combination with ponatinib, also known as AP24534 may abrogate the proliferation and survival of Ph-positive cells including T315I mutation. In this study, we investigated the combination therapy with a ponatinib and an alisertib by using the BCR-ABL positive cell line, K562, murine Ba/F3 cell line which was transfected with T315I mutant, ponatinib resistant Ba/F3 cells and T315I primary sample. Protein expression of Aurora A and B were increased in Ph-positive leukemia cells. 72 hours treatment of alisertib exhibits cell growth inhibition and induced apoptosis against K562 cells in a dose dependent manner. Alisertib also induced cell cycle arrest. The treatment of ponatinib exhibits cell growth inhibition partially against K562 cells in the presence of feeder cell (HS-5) conditioned media. We found that the treatment of alisertib abrogated the protective effects of HS-5 conditioned media in K562 cells. We investigated the alisertib activity against T315I positive cells. Alisertib potently induced cell growth inhibition of Ba/F3 cells ectopically expressing T315I mutation and induced cell cycle arrest. We investigated the efficacy between ponatinib and alisertib by using these cell lines. Combined treatment of Ba/F3 T315I cells with ponatinib and alisertib caused significantly more cytotoxicity than each drug alone. Ponatinib and alisertib were also effective against T315I primary samples. We examined the intracellular signaling of alisertib. Phosphorylation of Aurora A was inhibited in a time dependent manner. We also found the phosphorylation of histone H3 was also reduced in a dose dependent manner suggested that high concentration of alisertib also inhibits Aurora B activity. We next investigated by using ponatinib resistant Ba/F3 cells. In the ponatinib resistant cell lines, IC50 of ponatinib was up to 200 nM. BCR-ABL triple point mutations (T315I, E255K and Y253H) were detected by direct sequence analysis. The treatment of alisertib exhibits cell growth inhibition against Ba/F3 ponatinib resistant cells in the dose dependent manner. Alisertib induced cell cycle arrest in ponatinib resistant cells. Combined treatment of Ba/F3 ponatinib resistant cells with ponatinib and alisertib caused significantly more cytotoxicity. To assess the activity of alisertib and ponatinib, we performed to test on CML tumor formation in mice. We injected nude mice subcutaneously with 1×107 Ba/F3 T315I cells. A dose of 30 mg/kg/day p.o of ponatinib and 30 mg/kg/day p.o of alisertib inhibited tumor growth and reduced tumor volume compared with control mice. The treatments were well tolerated with no animal health concerns observed indicating the feasibility of alisertib combination strategies in the clinic. Data from this study suggested that administration of the ponatinib and Aurora inhibitor, alisertib may be a powerful strategy against BCR-ABL mutant cells including T315I. Disclosures: No relevant conflicts of interest to declare.

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