scholarly journals BH3-only protein Bim more critical than Puma in tyrosine kinase inhibitor–induced apoptosis of human leukemic cells and transduced hematopoietic progenitors carrying oncogenic FLT3

Blood ◽  
2009 ◽  
Vol 113 (10) ◽  
pp. 2302-2311 ◽  
Author(s):  
Amanda Nordigården ◽  
Maria Kraft ◽  
Pernilla Eliasson ◽  
Verena Labi ◽  
Eric W.-F. Lam ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Bone Marrow Cells ◽  
Treatment Options ◽  
Leukemic Cell ◽  
Therapeutic Interventions ◽  
Leukemic Cells ◽  
Leukemic Cell Lines ◽  
Induced Apoptosis

Abstract Constitutively activating internal tandem duplications (ITD) of FLT3 (FMS-like tyrosine kinase 3) are the most common mutations in acute myeloid leukemia (AML) and correlate with poor prognosis. Receptor tyrosine kinase inhibitors targeting FLT3 have developed as attractive treatment options. Because relapses occur after initial responses, identification of FLT3-ITD–mediated signaling events are important to facilitate novel therapeutic interventions. Here, we have determined the growth-inhibitory and proapototic mechanisms of 2 small molecule inhibitors of FLT3, AG1295 or PKC412, in hematopoietic progenitor cells, human leukemic cell lines, and primary AML cells expressing FLT3-ITD. Inactivation of the PI3-kinase pathway, but not of Ras–mitogen-activated protein (MAP) kinase signaling, was essential to elicit cytotoxic responses. Both compounds induced up-regulation of proapoptotic BH3-only proteins Bim and Puma, and subsequent cell death. However, only silencing of Bim, or its direct transcriptional activator FOXO3a, abrogated apoptosis efficiently. Similar findings were made in bone marrow cells from gene-targeted mice lacking Bim and/or Puma infected with FLT3-ITD and treated with inhibitor, where loss of Puma only provided transient protection from apoptosis, but loss of Bim preserved clonal survival upon FLT3-ITD inhibition.

scholarly journals The Tyrosine Kinase-Driven Networks of Novel Long Non-coding RNAs and Their Molecular Targets in Myeloproliferative Neoplasms

2021 ◽  
Vol 9 ◽  
Author(s):  
Nonthaphat Kent Wong ◽  
Shumeng Luo ◽  
Eudora Y. D. Chow ◽  
Fei Meng ◽  
Adenike Adesanya ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Kinase Inhibitors ◽  
Myeloproliferative Neoplasms ◽  
Copy Number Variants ◽  
Leukemic Cell ◽  
Myelogenous Leukemia ◽  
Leukemic Cells ◽  
Imatinib Resistance ◽  
Leukemic Cell Lines ◽  
Non Coding Rnas

Recent research has focused on the mechanisms by which long non-coding RNAs (lncRNAs) modulate diverse cellular processes such as tumorigenesis. However, the functional characteristics of these non-coding elements in the genome are poorly understood at present. In this study, we have explored several mechanisms that involve the novel lncRNA and microRNA (miRNA) axis participating in modulation of drug response and the tumor microenvironment of myeloproliferative neoplasms (MPNs). We identified novel lncRNAs via mRNA sequencing that was applied to leukemic cell lines derived from BCR-ABL1-positive and JAK2-mutant MPNs under treatment with therapeutic tyrosine kinase inhibitors (TKI). The expression and sequence of novel LNC000093 were further validated in both leukemic cells and normal primary and pluripotent cells isolated from human blood, including samples from patients with chronic myelogenous leukemia (CML). Downregulation of LNC000093 was validated in TKI-resistant CML while a converse expression pattern was observed in blood cells isolated from TKI-sensitive CML cases. In addition to BCR-ABL1-positive CML cells, the driver mutation JAK2-V617F-regulated lncRNA BANCR axis was further identified in BCR-ABL1-negative MPNs. Further genome-wide validation using MPN patient specimens identified 23 unique copy number variants including the 7 differentially expressed lncRNAs from our database. The newly identified LNC000093 served as a competitive endogenous RNA for miR-675-5p and reversed the imatinib resistance in CML cells through regulating RUNX1 expression. The extrinsic function of LNC000093 in exosomal H19/miR-675-induced modulation for the microenvironment was also determined with significant effect on VEGF expression.

Novel Tyrosine Kinase Inhibitors Trigger Drug Sensitivity of Primary CLL Cells by Controlling Glucosylation of Ceramides

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3905-3905
Author(s):  
Janine Schwamb ◽  
Valeska Feldhaus ◽  
Michael Baumann ◽  
Michaela Patz ◽  
Susanne Brodesser ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Conflicts Of Interest ◽  
Treatment Options ◽  
Cell Receptor ◽  
Lymphocytic Leukemia ◽  
Published Data ◽  
The Novel ◽  
Apoptosis Resistance

Abstract Abstract 3905 Background: Apoptosis resistance of chronic lymphocytic leukemia (CLL) cells is mediated by several pro-survival stimuli. In particular, engagement of the B-cell receptor (BCR), CD40-CD40 ligand (CD40L) interaction or stimulation by interleukin-(IL)-4 were identified as major factors to regulate chemoresistance. Sphingolipids are known to be involved in several metabolic pathways involved in chemoresitance. Therefore, we focused on ceramide as pro-apoptotic molecule and its counterpart glucosylceramide, which rather contributes to proliferation and survival. Methods and Results: Applying liquid chromatography electrospray ionization tandem mass spectrometry, we revealed a significant decrease of pro-apoptotic ceramide in BCR/IL-4/CD40L-stimulated primary CLL cells compared to untreated controls (p=0.0258, p=0.0478, p=0.0114). Anti-apoptotic glucosylceramide levels were significantly increased after BCR cross-linking (p=0.0435) while other stimuli caused no relevant change in glucosylceramide expression. We identified BCR engagement to catalyze the crucial modification of ceramide to glucosylceramide via the enzyme UDP-glucose ceramide glucosyltransferase (UGCG) (p=0.0001). Besides specific UGCG inhibitors, we could show for the first time that IgM-mediated UGCG expression was significantly inhibited by the novel and highly effective PI3Kδ and BTK inhibitors CAL-101 and PCI-32765, which were able to revert IgM-induced apoptosis resistance of CLL cells. Recently published data revealed sphingolipids to be essential for mediation of apoptosis via mitochondria. Therefore, we chose ABT-737 – a well-known and also mitochondria-targeting drug – as candidate partner for PI3Kδ and BTK inhibition. When combining each tyrosine kinase inhibitor with ABT-737, a synergistic apoptotic effect could be documented, even under protection by BCR stimulation. Conclusion: In summary, we could demonstrate that sphingolipids are critically involved in CLL pathogenesis. UGCG could be identified as drugable target by the novel kinase inhibitors CAL-101 and PCI-32765 resulting in even synergistic apoptosis following additional application of ABT-737. Sphingolipids seem to offer further targets providing novel treatment options in CLL. C.M.W. and L.P.F. contributed equally to this work. Disclosures: No relevant conflicts of interest to declare.

VEGF165 promotes survival of leukemic cells by Hsp90-mediated induction of Bcl-2 expression and apoptosis inhibition

Blood ◽  
2002 ◽  
Vol 99 (7) ◽  
pp. 2532-2540 ◽  
Author(s):  
Sergio Dias ◽  
Sergey V. Shmelkov ◽  
George Lam ◽  
Shahin Rafii
Keyword(s):  
Cell Lines ◽  
Specific Inhibitor ◽  
Leukemic Cell ◽  
Heat Shock Protein 90 ◽  
Mitogen Activated Protein Kinase ◽  
Leukemic Cells ◽  
Vegf Receptor ◽  
Autocrine Loop ◽  
Leukemic Cell Lines ◽  
Induced Apoptosis

Similar to endothelial cells (ECs), vascular endothelial growth factor (VEGF) induces Bcl-2 expression on VEGF receptor-positive (VEGFR+) primary leukemias and cell lines, promoting survival. We investigated the molecular pathways activated by VEGF on such leukemias, by performing a gene expression analysis of VEGF-treated and untreated HL-60 leukemic cells. One gene to increase after VEGF stimulation was heat shock protein 90 (Hsp90). This was subsequently confirmed at the protein level, on primary leukemias and leukemic cell lines. VEGF increased the expression of Hsp90 by interacting with KDR and activating the mitogen-activated protein kinase cascade. In turn, Hsp90 modulated Bcl-2 expression, as shown by a complete blockage of VEGF-induced Bcl-2 expression and binding to Hsp90 by the Hsp90-specific inhibitor geldanamycin (GA). GA also blocked the VEGF-induced Hsp90 binding to APAF-1 on leukemic cells, a mechanism shown to inhibit apoptosis. Notably, VEGF blocked the proapoptotic effects of GA, correlating with its effects at the molecular level. Earlier, we showed that in some leukemias, a VEGF/KDR autocrine loop is essential for cell survival, whereas here we identified the molecular correlates for such an effect. We also demonstrate that the generation of a VEGF/VEGFR autocrine loop on VEGFR+ cells such as ECs, also protected them from apoptosis. Infection of ECs with adenovirus-expressing VEGF resulted in elevated Hsp90 levels, increased Bcl-2 expression, and resistance to serum-free or GA-induced apoptosis. In summary, we demonstrate that Hsp90 mediates antiapoptotic and survival-promoting effects of VEGF, which may contribute to the survival advantage of VEGFR+cells such as subsets of leukemias.

scholarly journals Utilization of a colony assay to assess the variables influencing elimination of leukemic cells from human bone marrow with monoclonal antibodies and complement

Blood ◽  
1985 ◽  
Vol 65 (4) ◽  
pp. 945-950
Author(s):  
TW LeBien ◽  
DE Stepan ◽  
RM Bartholomew ◽  
RC Stong ◽  
JM Anderson
Keyword(s):  
Bone Marrow ◽  
Monoclonal Antibodies ◽  
Cell Lines ◽  
Bone Marrow Cells ◽  
Leukemic Cell ◽  
Leukemic Cells ◽  
Colony Assay ◽  
Leukemic Cell Lines ◽  
Human Leukemic Cells ◽  
Cell Colony

We have previously used a chromium-release assay to demonstrate that the cocktail of monoclonal antibodies BA-1, BA-2, BA-3, and complement can effectively lyse human leukemic cells in the presence of excess bone marrow. Using a leukemic cell colony assay, we have reinvestigated the variables influencing lysis of human leukemic cells (KM-3, HPB- NULL, NALM-6) in bone marrow using BA-1, BA-2, BA-3, and complement. Specific variables addressed included the concentration of excess bone marrow cells, the number of treatments, the presence or absence of DNase during the treatment, the combination of antibodies, and the sensitivity of different leukemic cell lines to lysis. Using the colony assay, the BA-1,2,3 cocktail was shown to be more effective than any single antibody or combination of two antibodies. We also determined that the concentration of excess bone marrow cells and number of treatments had a direct bearing on leukemic cell lysis. Although two cycles of treatment were significantly superior to one cycle, three cycles were not significantly superior to two cycles. Inclusion of DNase (10 micrograms/mL) was a critical adjunct that eliminated clumping and facilitated plating cells in the colony assay. Finally, we could show that striking differences existed in the sensitivity of the leukemic cell lines to lysis with the BA-1,2,3 cocktail and complement. NALM-6 cells were the most sensitive (approximately four logs of kill), and KM-3 cells were the most resistant (less than two logs of kill). Our results strongly support the utility of sensitive leukemic cell colony assays in the analysis of marrow treatment variables in autologous bone marrow transplantation.

Inhibition of WT1 and bcl2 in leukemic cell lines by small interfering RNA (siRNA)

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 16504-16504
Author(s):  
W. Glienke ◽  
E. Milz ◽  
N. Bauer ◽  
L. Bergmann
Keyword(s):  
Cell Proliferation ◽  
Cell Lines ◽  
Leukemia Cell ◽  
Leukemic Cell ◽  
Leukemic Cells ◽  
Transfected Cells ◽  
Leukemic Cell Lines ◽  
Blast Cells ◽  
Induced Apoptosis ◽  
Interfering Rna

16504 The expression of Wilm‘s tumor gene-1 (wt1) and bcl-2 is considered to have a proliferating and survival supporting effect in leukemia blast cells. The downregulation of wt1 by means of antisense-oligonucleotides and ribozymes revealed an inhibition of cell proliferation and induction of cell death. Here we describe the effect of siRNA against wt1 and bcl-2 in leukemic cell lines. RT-PCR and western blot analyses were performed to examine wt1 and bcl-2 gene expression in transfected leukemia cell lines. Apoptosis was detected with FACS analysis. K562 and HL-60 cell lines transfected with wt1 siRNA showed decreasing levels of wt1 mRNA and protein expression after 24 and 48 hours. The cell proliferation was reduced between 45% and 76% 48 hours after transfection, and apoptosis increased from 6.6 % in control cells to 12.2 % 24 hours after transfection in transfected cells. 48 hours after transfection the amount of apoptotic cells increased up to 45 % in transfected cells. Bcl-2 siRNA only induced apoptosis in about 15% of the cells. The combination of wt1 and bcl-2 siRNA had no additive effect on the induction of apoptosis. The expression of wt1 seems to be more important for cell survival than expression of the anti-apoptotic gene bcl-2. We therefore consider siRNA targeting human wt1 as possible tool against leukemic cells overexpressing wt1. No significant financial relationships to disclose.

scholarly journals Pharmacotherapy Options in Advanced Renal Cell Carcinoma: What Role for Pazopanib?

2011 ◽  
Vol 5 ◽  
pp. CMO.S6087 ◽  
Author(s):  
Michael R. Harrison
Keyword(s):  
Renal Cell Carcinoma ◽  
Tyrosine Kinase ◽  
Cell Carcinoma ◽  
Tyrosine Kinase Inhibitors ◽  
Renal Cell ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Treatment Options ◽  
Tumor Biology ◽  
Mammalian Target Of Rapamycin

Over the last 6 years, the treatment of metastatic renal cell carcinoma (mRCC) has undergone dramatic changes. A better understanding of the pathogenesis and tumor biology of sporadic renal cell carcinoma has led to the approval of 6 drug regimens: 3 oral multi-targeted tyrosine-kinase inhibitors (sorafenib, sunitinib, and pazopanib), 2 inhibitors of the mammalian target of rapamycin (temsirolimus and everolimus), and 1 monoclonal antibody against the vascular endothelial growth factor (bevacizumab). Pazopanib, a multi-targeted tyrosine kinase inhibitor that targets VEGFR-1, -2, and-3; PDGFR-α and PDGFR-β, and c-Kit, was approved for the treatment of mRCC in October 2009, several years after the other drugs in its class. The efficacy and safety of pazopanib in Phase I, II, and III trials will be examined and its role in mRCC treatment will be described. Future studies that may clarify pazopanib's role in mRCC will be discussed. Based on pazopanib's demonstrated efficacy in treatment-naïve and cytokine-refractory patients, along with a seemingly favorable toxicity profile compared with other multi-targeted tyrosine-kinase inhibitors, pazopanib may have a unique niche in the armamentarium of treatment options for mRCC. Results from ongoing studies are awaited to confirm pazopanib's favorable efficacy-toxicity ratio, especially in comparison with the previous first-line standard-of-care, sunitinib.

A Novel Compound Inhibits Chronic Myeloid Leukemia Via Upregulating Apoptosis

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 5559-5559
Author(s):  
Jiajia Xin ◽  
Dandan Yin ◽  
Wei Fu ◽  
Hui-Jie Zhang ◽  
Yaozhen Chen ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Chronic Myeloid Leukemia ◽  
Tyrosine Kinase ◽  
Myeloid Leukemia ◽  
Kinase Inhibitors ◽  
Bone Marrow Cells ◽  
Conflicts Of Interest ◽  
Fusion Gene ◽  
Leukemic Cells ◽  
Hematopoietic Stem

Abstract Chronic myeloid leukemia (CML) is a myeloid proliferative disorder mainly result from chimeric protein BCR-ABL1 encoded by a fusion gene at the t(9;22) (q34;q11) chromosomal translocation. Intrinsically, this recombined protein results in an increased tyrosine kinase (TK) activity that directly related to hematopoietic stem cell malignant proliferation. Consequently, the drugs derived from tyrosine kinase inhibitors (TKI) have been developed as an infective therapy, and greatly improved patients survival in clinic. Unfortunately, single TKI administration led to toxicities or tolerance in long-term treated CML patients. Even worse is, about 5% CML patients were not caused by bcr-abl gene mutation. Thus better medicines are badly needed to compensate CML therapy. Herein, we investigated the undefined function of a biscoumarins. The new synthesized compound exhibited a null toxicity on HUVECs but intensive toxicity on K562 leukemic cells. Subsequent results demonstrated that it efficiently inhibited the expansion of human CML cell line and bone marrow cells of SCL-tTA-BCL/ABL transgenic model mice via increased apoptosis. Critically, we also showed that CD34+ bone marrow leukemic cells collected from patients underwent more apoptosis after treated by the biscoumarins derivate. To extend these results into vivo, we observed a prolonged survival of bcr-abl transgenic mice treated by derivate mono-therapy or combination with imatinib compared to those of untreated or imatinib-treated CML mice. All together, these results indicated that this biscoumarins derivate may have novel potential as a therapeutic agent against CML. Disclosures No relevant conflicts of interest to declare.

Targeting epidermal growth factor receptor pathway with irreversible tyrosine kinase inhibitor

2019 ◽  
Vol 44 (1) ◽  
pp. 62-69
Author(s):  
Fatma Sagir ◽  
Asuman Demiroglu-Zergeroglu
Keyword(s):  
Tyrosine Kinase ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Treatment Options ◽  
Growth Factor Receptor ◽  
Central Anatolia ◽  
Pcr Analysis ◽  
Dependent Manner ◽  
Rt Pcr ◽  
Proliferative Effect

Abstract Background Malignant mesothelioma (MM) is an endemic disease around central Anatolia region in Turkey, where people are exposed to erionite- and asbestos-contaminated soil. Aberrant EGFR signalling has implicated in several cancers including MMs. Tyrosine kinase inhibitors are new treatment options harbouring deregulated signalling network components. In this study, we aimed to investigate anti-proliferative effect of CL-387,785 in MM cells. Materials and methods Alteration of cell proliferation was evaluated with using MTS assay. Profile of EGFR, ERK, AKT, JNK and p38 proteins and ELK-1, JUN, STAT1, STAT3 and STAT5 genes were analysed by western blot and RT-PCR, respectively. Results Viability of MM cells was inhibited in dose- and time-dependent manner. CL-387,785 affected MM cells earlier and at higher extent compared to the mesothelial cells. CL-387,785 treatments suppressed EGF-induced phosphorylation of EGFR, ERK, AKT, STAT3 and STAT5 but not SAPK/JNK and p38 in SPC212 cells. RT-PCR analysis showed that expression of p21 increased, while Cyclin D and c-jun expressions decreased in SPC212 cells. However, ELK-1, STAT3 and STAT5, expressions did not change. Conclusion Our results propose that CL-387,785 could be an efficacious agent in the treatment of MMs with uncontrolled EGFR signalling.

scholarly journals Comment on “PP2A inhibition sensitizes cancer stem cells to ABL tyrosine kinase inhibitors in BCR-ABL human leukemia”

2019 ◽  
Vol 11 (501) ◽  
pp. eaau0416 ◽  
Author(s):  
Danilo Perrotti ◽  
Anupriya Agarwal ◽  
Claire M. Lucas ◽  
Goutham Narla ◽  
Paolo Neviani ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cancer Stem Cells ◽  
Tyrosine Kinase ◽  
Tyrosine Kinase Inhibitor ◽  
Tyrosine Kinase Inhibitors ◽  
Kinase Inhibitors ◽  
Kinase Inhibitor ◽  
Human Leukemia ◽  
Abl Tyrosine Kinase ◽  
Induced Apoptosis

LB100 does not sensitize CML stem cells to tyrosine kinase inhibitor–induced apoptosis.

scholarly journals Retinoid Induced Apoptosis in Leukemia Cells Through a Retinoic Acid Nuclear Receptor-Independent Pathway

Blood ◽  
1997 ◽  
Vol 89 (12) ◽  
pp. 4470-4479 ◽  
Author(s):  
C. Alex Hsu ◽  
Arun K. Rishi ◽  
Xiao Su-Li ◽  
Tonya M. Gerald ◽  
Marcia I. Dawson ◽  
...  
Keyword(s):  
Retinoic Acid ◽  
Nuclear Receptor ◽  
Kinase Inhibitor ◽  
Therapeutic Potential ◽  
Leukemic Cell ◽  
Myelogenous Leukemia ◽  
Cyclin Dependent Kinase Inhibitor ◽  
Leukemic Cell Lines ◽  
Acute Myelogenous ◽  
Induced Apoptosis

Abstract Trans retinoic acid (RA) has proven to be a potent therapeutic agent in the treatment of acute promyelocytic leukemia. Unfortunately, other subtypes of acute myelogenous leukemia are resistant to the antiproliferative and differentiating effects of RA. In this report, we describe a novel retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (AHPN; CD437) that not only totally inhibits the proliferation of RA-resistant leukemic cell lines HL-60R and K562 but also induces apoptosis in these cells. Exposure of HL-60R to CD437 results in the rapid (within 30 minutes) increase of the cyclin-dependent kinase inhibitor p21waf1/cip1 as well as GADD45 mRNA. Manifestations of CD437-mediated programmed cell death are noted within 2 hours, as indicated by both the cleavage and activation of the CPP32 protease and cleavage of poly (ADP-ribose) polymerase. This is followed by cleavage of bcl-2 and internucleosomal DNA degradation. HL-60R cells do not express the retinoid nuclear receptor RARβ and RARγ and express a truncated RARα. Thus, CD437 induction of p21waf1/cip1 and GADD45 mRNAs and apoptosis occurs through a unique mechanism not involving the retinoid nuclear receptors. CD437 represents a unique retinoid with therapeutic potential in the treatment of myeloid leukemia.

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