scholarly journals Zinc Finger Protein X-Linked Exhibits Pro-Leukemia Activity Via WNT3 in Chronic Myeloid Leukemia Stem/Progenitor Cells

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4247-4247
Author(s):  
Xiuyan Zhang ◽  
Yu Wang ◽  
Lun Xiao ◽  
Haixia Zhou ◽  
Li Zhu ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Progenitor Cells ◽  
Zinc Finger ◽  
Myeloid Leukemia ◽  
Zinc Finger Protein ◽  
Qrt Pcr ◽  
Finger Protein ◽  
Healthy Donors ◽  
Cd34 Cells ◽  
Protein X

Abstract Zinc Finger protein, X-linked (ZFX) is a transcriptional regulator, which controls the self-renewal of both embryonic and hematopoietic stem cells and participates in pathogenesis of various cancers. Zfx deficiency impairs Notch intracellular domain (NotchIC) induced acute T-cell leukemia (T-ALL) or MLL-AF9 induced acute myeloid leukemia (AML) in mice models. However, the function of ZFX in chronic myeloid leukemia (CML) stem/progenitor cells has not been elucidated yet. In the present study, qRT-PCR analysis showed that ZFX expression was significantly higher in CD34+ cells from CML patients in chronic phase (CP) (n=8, 3.1-fold, P=0.0052) and patients in blast crisis (BC) (n=8, 18.6-fold, P=0.0050) compared with that in healthy donors (n=4). Two independent shRNA sequences against ZFX were delivered in CD34+ cells with lentiviral vector. The silence of ZFX had a stronger inhibitory effect on colony-forming cell (CFC) ability of CML CD34+ cells (75±5%) than that of healthy donor CD34+ cells (44±5%). Furthermore, ZFX silencing augmented Imatinib Mesylate (IM) sensitivity of CML CD34+ cells, especially in IM-resistant samples; due to the fact that ZFX silencing increased apoptosis induced by IM. To obtain the molecular insights of how ZFX acts, we generated transcriptome data comparing ZFX silenced CML CD34+ cells with control cells. qRT-PCR data validated that ZFX silencing caused a significantly declined expression of WNT3 in K562, MEG-01 and CML CD34+ cells (n=5). In addition, ZFX silencing decreased WNT3 protein expression as well. Interestingly, WNT3 had significantly higher expression in CD34+ cells from patients in CP (n=10, 5-fold, P=0.0006) compared with that in healthy donors (n=8). Silence of WNT3 inhibited the growth of K562 cells and enhanced IM sensitivity of these cells as well. Overexpression of WNT3 restored the growth inhibition and IM hypersensitivity upon ZFX silencing. Chromatin immunoprecipitation (ChIP) analysis revealed that ZFX was able to bind with WNT3 promoter, and luciferase assay showed that ZFX silencing significantly decreased the activity of WNT3 promoter. Finally, we also found that the expressions of c-Myc and cyclin D1 were reduced by ZFX silencing or WNT3 silencing, suggesting decreased WNT/Catenin signaling. Taken together, we have demonstrated that ZFX is aberrantly expressed in CML stem/progenitor cells, and it modulates the growth and IM response of CML stem/progenitor cells via wnt/Catenin pathway indicating ZFX is a new regulator of CML stem/progenitor cells, which deepens the understanding of CML pathology and potentially provides clues for novel therapies against this disease. Disclosures No relevant conflicts of interest to declare.

Nilotinib exerts equipotent antiproliferative effects to imatinib and does not induce apoptosis in CD34+ CML cells

Blood ◽  
2007 ◽  
Vol 109 (9) ◽  
pp. 4016-4019 ◽  
Author(s):  
Heather G. Jørgensen ◽  
Elaine K. Allan ◽  
Niove E. Jordanides ◽  
Joanne C. Mountford ◽  
Tessa L. Holyoake
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Progenitor Cells ◽  
Imatinib Mesylate ◽  
Myeloid Leukemia ◽  
Caspase 3 ◽  
Inhibitory Concentration ◽  
Antiproliferative Effects ◽  
Cd34 Cells ◽  
Stem And Progenitor Cells ◽  
Predominant Effect

Abstract Chronic myeloid leukemia (CML) stem and progenitor cells overexpress BcrAbl and are insensitive to imatinib mesylate (IM). We therefore investigated whether these cells were efficiently targeted by nilotinib. In K562, the inhibitory concentration (IC50) of nilotinib was 30 nM versus 600 nM for IM, consistent with its reported 20-fold-higher potency. However, in primary CD34+ CML cells, nilotinib and IM were equipotent for inhibition of BcrAbl activity, producing equivalent but incomplete reduction in CrkL phosphorylation at 5 μM. CML CD34+ cells were still able to expand over 72 hours with 5 μM of either drug, although there was a concentration-dependent restriction of amplification. As for IM, the most primitive cells (CFSEmax) persisted and accumulated over 72 hours with nilotinib and remained caspase-3 negative. Furthermore, nilotinib with IM led to further accumulation of this population, suggesting at least additive antiproliferative effects. These results confirmed that, like IM, the predominant effect of nilotinib is antiproliferative rather than proapoptotic.

scholarly journals Zinc finger protein X-linked promotes expansion of EpCAM+cancer stem-like cells in hepatocellular carcinoma

2017 ◽  
Vol 11 (5) ◽  
pp. 455-469 ◽  
Author(s):  
Chao Wang ◽  
Si-yuan Fu ◽  
Ming-da Wang ◽  
Wen-bo Yu ◽  
Qin-shu Cui ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Zinc Finger ◽  
Zinc Finger Protein ◽  
Finger Protein ◽  
Protein X

scholarly journals Patients with Chronic Myeloid Leukemia Show Different Modulation of MYB-Dependent Oncogenic Pathway in the Course of Hematopoietic Differentiation upon Sensitivity to the TKI Treatment

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 1243-1243
Author(s):  
Klara Srutova ◽  
Nikola Curik ◽  
Koblihova Jitka ◽  
Filipp Savvulidi ◽  
Hana Klamova ◽  
...  
Keyword(s):  
Cell Differentiation ◽  
Chronic Myeloid Leukemia ◽  
Mouse Model ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
De Novo ◽  
Qrt Pcr ◽  
Healthy Donors ◽  
Tki Resistance ◽  
Tki Treatment

Abstract Introduction: Inhibition of the BCR-ABL protein activity by tyrosine kinase inhibitors (TKIs) plays crucial role in leukemic transformation from the chronic phase (CP) of the chronic myeloid leukemia (CML) into fatal blast crisis (BC). However 20 - 30 % of CML patients develop resistance to the TKIs. Beside mutations in BCR-ABL kinase domain, BCR-ABL independent mechanisms of acquired TKIs resistance including microRNAs (miR) may be also involved. A significant reduction of miR-150 levels associates with CML progression. MiR-150 is an inhibitor of the Myeloblastoma oncogene c-MYB, which is required for BCR-ABL-dependent leukemogenesis in a mouse model of CML-BC. Recently MYB was found to positively regulating another miR, miR-155, that inhibits tumor suppressor and pro-differentiation factor PU.1 in AML/MPS mouse model. PU.1 is a major regulator of myelopoiesis whose levels require precise guidance. We recently reported increased levels of miR-155 in CML-BC. Objectives: We hypothesize that BCR-ABL activity together with low levels of miR-150 activates putative oncogenic signaling pathway MYB/miR-155/PU.1 in CML leading to a progressive blockade of cell differentiation and possibly also of resistance to TKIs. Material and Method: Bone marrow (BM) cells of CML-CP patients at the time of diagnosis (n=10), and of treated patients either sensitive (n=8) or resistant (n=11) to TKIs, were FACS sorted for CD34 and CD38 into subpopulations representing the stages of cell differentiation. CD34+ and CD34- leukocytes from peripheral blood of healthy donors (n=10) were isolated by MACS and used as control. Levels of miR-150, BCR-ABL, MYB, miR-155 and PU.1 were determined by qRT-PCR. Expression of surface differentiation markers on BM cells was determined using flow cytometry at the time of diagnosis (n=10) and upon TKIs resistance (n=5). The effect of miR-150 overexpression and BCR-ABL inhibition was studied in CML-BC cell line K562 using nucleofection of the synthetic miR-150 and siRNA BCR-ABL (and by cell cultivation with TKI imatinib). mRNA and protein expression of BCR-ABL, MYB and miR-150 levels were determined by qRT-PCR and immunoblotting. Results: In the groups of healthy donors and de novo diagnosed CML patients we observed significant positive or negative correlations of expression levels between studied molecules among the sorted cell subpopulations, which outlined the activity of the putative pathway BCR-ABL/miR-150/MYB/miR-155/PU.1 in CML-CP. Interestingly, in the group of patients resistant to TKI, we found that correlation between MYB and miR-155 was not observed suggesting this pathway is deregulated upon TKI resistance. Conversely, we found gain of negative correlation between expression of MYB and PU.1 in the group of patients responding to TKI suggesting that MYB and PU.1 oppose each other upon normal cell differentiation. We also observed significant differences of the surface marker phenotype profiles between BM cells of de novo diagnosed CML patients and patients resistant to TKIs treatment. While relatively differentiated (granulocyte) CD34- CD38- CD11b+ CD14- population presents about 7 % of BM cells for the group of patients at diagnosis, it comprises only 0.3 % of BM cells for resistant group (P= 0.0027) indicating that TKI resistance associates with significant blockade of myeloid differentiation. We next utilized K562 cells showing that levels of miR-150 significantly increased after BCR-ABL inhibition by imatinib (P=0.0017) and also upon BCR-ABL knockdown with siRNA (P=0.002). This suggests that miR-150 is regulated by BCR-ABL. Similarly, MYB mRNA and protein levels were markedly decreased upon miR-150 overexpression and this was enhanced by inhibition of BCR-ABL activity with imatinib. Conclusions: Dysregulation of BCR-ABL/miR-150/MYB/miR-155/PU.1 pathway was observed in CML stages and stage-specific cell populations in relation to TKI-sensitivity and disease progression. Our model consists of the BCR-ABL upregulating MYB both through miR-150 inhibition and by other downstream mechanisms by additive effect, thus the cooperation of miR-150 and imatinib through inhibiting MYB may represent an important barrier to CML progression. Even more our results show that regulation of miR-155 and PU.1 may play role in resistance to TKI treatment. Supported by GAUK 178215 and by project 00023736 from the Czech Ministry of Health Disclosures Klamova: Bristol Myers-Squibb: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding. Machova Polakova:Bristol Myers-Squibb: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding.

scholarly journals Zinc Finger Protein 521 Regulates Early Hematopoiesis through Cell-Extrinsic Mechanisms in the Bone Marrow Microenvironment

2018 ◽  
Vol 38 (17) ◽  
Author(s):  
Courtney J. Fleenor ◽  
Tessa Arends ◽  
Hong Lei ◽  
Josefine Åhsberg ◽  
Kazuki Okuyama ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Progenitor Cells ◽  
Zinc Finger ◽  
Zinc Finger Protein ◽  
Cell Types ◽  
Bone Marrow Microenvironment ◽  
Cancer Therapies ◽  
Hematopoietic Stem ◽  
Finger Protein ◽  
Stem And Progenitor Cells

ABSTRACTZinc finger protein 521 (ZFP521), a DNA-binding protein containing 30 Krüppel-like zinc fingers, has been implicated in the differentiation of multiple cell types, including hematopoietic stem and progenitor cells (HSPC) and B lymphocytes. Here, we report a novel role for ZFP521 in regulating the earliest stages of hematopoiesis and lymphoid cell development via a cell-extrinsic mechanism. Mice with inactivatedZfp521genes (Zfp521−/−) possess reduced frequencies and numbers of hematopoietic stem and progenitor cells, common lymphoid progenitors, and B and T cell precursors. Notably, ZFP521 deficiency changes bone marrow microenvironment cytokine levels and gene expression within resident HSPC, consistent with a skewing of hematopoiesis away from lymphopoiesis. These results advance our understanding of ZFP521's role in normal hematopoiesis, justifying further research to assess its potential as a target for cancer therapies.

scholarly journals Expression of zinc-finger protein X-linked, ZFX, is associated with enhanced survival in patients with breast cancer.

2020 ◽  
Author(s):  
Shahan Mamoor
Keyword(s):  
Breast Cancer ◽  
Zinc Finger ◽  
Survival Data ◽  
Zinc Finger Protein ◽  
Metastatic Breast ◽  
Stage Iv ◽  
Metastatic Tumor ◽  
Finger Protein ◽  
Tumor Tissues ◽  
Protein X

We mined published tumor transcriptome data with paired survival data to discover genes associated with survival outcomes in breast cancer (1, 2). We found that the zinc-finger protein X-linked ZFX (3, 4) was among the genes most differentially expressed in both primary and metastatic tumor tissues when comparing tumor transcriptomes based on survival at 24 months. ZFX expression was significantly higher in the metastatic tumors of patients surviving greater than 24 months, suggesting that increased ZFX expression confers a survival benefit to patients with stage IV metastatic breast cancer.

Retroviral activation of a novel gene encoding a zinc finger protein in IL-3-dependent myeloid leukemia cell lines

Cell ◽  
1988 ◽  
Vol 54 (6) ◽  
pp. 831-840 ◽  
Author(s):  
Kazuhiro Morishita ◽  
Diana S. Parker ◽  
Michael L. Mucenski ◽  
Nancy A. Jenkins ◽  
Neal G. Copeland ◽  
...  
Keyword(s):  
Cell Lines ◽  
Zinc Finger ◽  
Myeloid Leukemia ◽  
Zinc Finger Protein ◽  
Leukemia Cell ◽  
Gene Encoding ◽  
Novel Gene ◽  
Finger Protein ◽  
Leukemia Cell Lines ◽  
Myeloid Leukemia Cell

ZNF521 Is a Zinc Finger Protein That Prevents Differentiation Of Human MLL-AF9-Positive Myeloid Leukemic Cells

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 1255-1255
Author(s):  
Giulia Morello ◽  
Sanja Aveic ◽  
Sonia Minuzzo ◽  
Barbara Michielotto ◽  
Silvia Bresolin ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
Cell Differentiation ◽  
Zinc Finger ◽  
Zinc Finger Protein ◽  
Leukemic Cells ◽  
Flow Cytometry Analysis ◽  
Hematopoietic Stem ◽  
Qrt Pcr ◽  
Finger Protein

Abstract Introduction MLL- rearranged acute myeloid leukemia (AML) remains a type of leukemia difficult to treat, for which alternative and more adequate treatment options are still urgently needed. The zinc finger protein 521 (ZNF521/EHZF) is a protein with multiple zinc finger domains that plays an essential role in the homeostasis of the hematopoietic stem/progenitor cell compartment. ZNF521 mRNA is highly expressed in hematopoietic stem and progenitor cells and its levels rapidly decrease during cell differentiation. Gene expression studies demonstrated that ZNF521 transcripts are abundantly expressed in MLL-rearranged AML. However, the functional significance of this up-regulation in AML with MLLrearrangements remains largely unknown. Methods and results Quantitative RT-PCR analysis (qRT-PCR) confirmed that ZNF521 expression was significantly up regulated in a cohort of MLL-rearranged pediatric AML patients (n=80) compared with other AML subtypes (n=30) together with healthy bone marrow samples (n=7, p<0.0001), and AML cell lines with MLL fusion (THP-1, NOMO-1, ML2). To investigate the role of ZNF521, we performed shRNA-mediated knockdown of ZNF521 in MLL-rearranged AML cell lines THP-1 and NOMO-1, in which a reduced transcript levels of 60-70% resulted in a severe reduction of proliferation and largely abolished colony formation in methylcellulose, where residual colonies were also smaller than control. Next, flow-cytometry analysis showed that observed proliferation reduction was associated with a block of cell cycle in G1 phase (shRNA/control vs shRNA/ZNF521 G1=45.4% vs G1=60.4%, n=3, p<0.05) and a late cell death induction (Annexin/PI positive cells: shRNA/control 21.4±0.5% vs shRNA/ZNF521 30.1±0.3% 3 weeks, n=3, p<0.0001). Subsequently, morphology analysis of May-Grunwald-Giemsa stained cytospins identified a large number of monocytic cells differentiating into macrophages. This observation was further validated by flow-cytometry analysis that confirmed the increased levels of CD11b and CD14 antigens as sign of monocytic differentiation, indicating a tendency of ZNF521 when over-expressed to prevent cell differentiation. Then, we treated THP-1 cells with ATRA to induce differentiation and demonstrated by qRT-PCR a significant reduction of ZNF521 mRNA expression, supporting its role in blocking differentiation in MLL-rearranged leukemic cells. Hence, to validate the specificity of these effects in vivo, we transplanted leukemic bone marrow cells from different MLL-AF9 AML pediatric patients (n=4) into immunodeficient mice. All mice developed AML by 7 to 9 weeks after transplantation. Then, the ex vivo cells were transduced with ZNF521 shRNA and showed morphology changes similar to those observed in vitro, with typical features of maturation. Conclusions Collectively, these results demonstrate that ZNF521 plays an important role in MLL-AF9-induced AML leukemia wherein it maintains a block of differentiation. Thus, our findings make ZNF521 a novel attractive target for therapeutic intervention in MLL-rearranged AML. However, further studies on the function of ZNF521 in MLL-rearranged AML and on the possibility to block it are required. Disclosures: No relevant conflicts of interest to declare.

Sign in / Sign up

Export Citation Format

Share Document