scholarly journals Molecular Mechanism and Optimal Treatment Strategy in Acute Myeloid Leukemia with Resistance to Drugs and Radiation By NVP-LED225

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 3691-3691 ◽  
Author(s):  
Fanyi Meng ◽  
Xiaodong Li ◽  
Bingjie Ding ◽  
Kaikai Huang ◽  
Qiuhua Zhu ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Myeloid Leukemia ◽  
Hedgehog Signaling ◽  
Leukemia Cells ◽  
Hedgehog Signaling Pathway ◽  
Treatment Groups ◽  
Gli 1 ◽  
Refractory Aml

Abstract PURPOSE: Total body irradiation (TBI) combined with chemotherapy is currently the most effective procedure of traditional preparative myeloablative regimen. However, resistance to chemotherapy in refractory acute myeloid leukemia (AML) is associated with short-time recurrence after Allo-HSCT. To investigate the mechanism of Hedgehog signaling pathway resulting in resistance, we used primary AML cells originated in refractory patients and 3 cell lines including HL60, HL60/ADR (a adriamycin-resistant cells), and HL60/RX (a radiation-resistant cell line established from HL60) as cellular modes to examine the expression of p-IGF-1R, IRS-1, p-Akt, Gli-1, MRP1, Bcl-2, and explored the safety and efficacy of NVP-LDE225 (an inhibitor of Hedgehog pathway) for enhancing the sensitivity to treatment in refractory leukemia in vitro and in vivo. Methods: The expression of Hedgehog signaling pathway was measured in 3 leukemia cell lines, and primary leukemia cells originated in refractory AML patients and non-refractory AML patients using western blot technique. In in vitro experiments, HL60/ADR cells and HL60/RX cells were treated with DMSO (control) or NVP-LDE225 for 48 h, and then assigned in six groups respectively: (a) Control, (b) ADM alone, (c) Radiation alone (d) NVP-LDE225 alone, (e) NVP-LDE225+ADM, (f) NVP-LDE225+Radiation. Flow cytometry, MTT assay and Western-Blot were performed separately to detect apoptosis, adriamycin uptake rate, proliferation inhibit rate and the expression of MRP1, p-IGF-1R, IRS-1, p-Akt, Gli-1, and Bcl-2. Furthermore, based on the results in vitro, the serial tumor volumes, general condition of the mice, complete blood counts, multiple organs injury, and the expression levels of hedgehog signaling pathway were used to detect the antitumor efficacy and toxicity of NVP-LDE225 in HL60/ADR and HL/RX xenograft model. Results: Our result showed that, compared with leukemia cells in non-refractory AML patients and HL60 cells, the expression of hedgehog signaling pathway protein was significantly elevated in refractory AML, HL60/ADR and HL60/RX cells(P<0.01). In addition, we also observed that NVP-LDE225 (10µM) could reverse ADM, DNR, HHT, and Ara-c resistance in HL60/ADR cells. Combining ADM with NVP-LDE225 (20µM) could markedly increase apoptosis and ADM positive rate of intracellular fluorescence detection than other groups (P<0.05). Moreover, combination of NVP-LDE225 with radiation could significantly increase radiation-induced apoptosis and exhibit higher expression of phosphorylation of histone H2AX and BAK than any other single treatment groups both in HL60/RX and HL60/ADR cells(P<0.05). In vivo, both in HL60/RX and HL60/ADR mice model, combination of NVP-LDE225 simultaneously and post 2 days or 5 days with ADM or radiation all presented significantly antitumor effect and high survival rate compared with the control or single agent mice (P<0.01), but there were no significant differences between the three combined treatment groups. Within the combination- and ADM-treated groups, nadir of the white blood cell and platelet counts were reached in day 8 with a gradual recovery starting at day 11. Finally, decrease in IRS-1, Gli-1, p-AKT, and NF-kb expressions were observed after treating with NVP-LDE225 in vitro and in tumor tissue. None of the pathological lesion in the heart, liver, kidney, brain, and lung was observed among all groups. Conclusion: The findings from this study demonstrated that Gli-1/p-Akt/NF-kb pathway play a key role for resistance to both drug and irradiation, and suggested that the combination of hedgehog pathway inhibitor (NVP-LDE225) with chemotherapy or radiotherapy could significantly enhance the antitumor activity via overcoming chemoresistance or radioresistance. The myelosuppression and toxicity could be well tolerated Disclosures No relevant conflicts of interest to declare.

scholarly journals The PI3K Inhibitor XH30 Enhances Response to Temozolomide in Drug-Resistant Glioblastoma via the Noncanonical Hedgehog Signaling Pathway

2021 ◽  
Vol 12 ◽  
Author(s):  
Ming Ji ◽  
Zhihui Zhang ◽  
Songwen Lin ◽  
Chunyang Wang ◽  
Jing Jin ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Hedgehog Signaling ◽  
Kinase Inhibitor ◽  
Therapeutic Option ◽  
Hedgehog Signaling Pathway ◽  
Orthotopic Mouse Model ◽  
Cycle Arrest ◽  
The Central Nervous System

Glioblastoma multiforme (GBM) is the most common malignant tumor of the central nervous system. Temozolomide (TMZ)–based adjuvant treatment has improved overall survival, but clinical outcomes remain poor; TMZ resistance is one of the main reasons for this. Here, we report a new phosphatidylinositide 3-kinase inhibitor, XH30; this study aimed to assess the antitumor activity of this compound against TMZ-resistant GBM. XH30 inhibited cell proliferation in TMZ-resistant GBM cells (U251/TMZ and T98G) and induced cell cycle arrest in the G1 phase. In an orthotopic mouse model, XH30 suppressed TMZ-resistant tumor growth. XH30 was also shown to enhance TMZ cytotoxicity both in vitro and in vivo. Mechanistically, the synergistic effect of XH30 may be attributed to its repression of the key transcription factor GLI1 via the noncanonical hedgehog signaling pathway. XH30 reversed sonic hedgehog–triggered GLI1 activation and decreased GLI1 activation by insulin-like growth factor 1 via the noncanonical hedgehog signaling pathway. These results indicate that XH30 may represent a novel therapeutic option for TMZ-resistant GBM.

scholarly journals Inhibition of EZH2 by chidamide exerts antileukemia activity and increases chemosensitivity through Smo/Gli-1 pathway in acute myeloid leukemia

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Xuejie Jiang ◽  
Ling Jiang ◽  
Jiaying Cheng ◽  
Fang Chen ◽  
Jinle Ni ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Histone Deacetylases ◽  
Myeloid Leukemia ◽  
Hdac Inhibitors ◽  
Annexin V ◽  
Fluorescein Isothiocyanate ◽  
Gli 1 ◽  
Acute Myeloid

Abstract Background Epigenetic dysregulation plays important roles in leukemogenesis and the progression of acute myeloid leukemia (AML). Histone acetyltransferases (HATs) and histone deacetylases (HDACs) reciprocally regulate the acetylation and deacetylation of nuclear histones. Aberrant activation of HDACs results in uncontrolled proliferation and blockade of differentiation, and HDAC inhibition has been investigated as epigenetic therapeutic strategy against AML. Methods Cell growth was assessed with CCK-8 assay, and apoptosis was evaluated by flow cytometry in AML cell lines and CD45 + and CD34 + CD38- cells from patient samples after staining with Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI). EZH2 was silenced with short hairpin RNA (shRNA) or overexpressed by lentiviral transfection. Changes in signaling pathways were detected by western blotting. The effect of chidamide or EZH2-specific shRNA (shEZH2) in combination with adriamycin was studied in vivo in leukemia-bearing nude mouse models. Results In this study, we investigated the antileukemia effects of HDAC inhibitor chidamide and its combinatorial activity with cytotoxic agent adriamycin in AML cells. We demonstrated that chidamide suppressed the levels of EZH2, H3K27me3 and DNMT3A, exerted potential antileukemia activity and increased the sensitivity to adriamycin through disruption of Smo/Gli-1 pathway and downstream signaling target p-AKT in AML cells and stem/progenitor cells. In addition to decreasing the levels of H3K27me3 and DNMT3A, inhibition of EZH2 either pharmacologically by chidamide or genetically by shEZH2 suppressed the activity of Smo/Gli-1 pathway and increased the antileukemia activity of adriamycin against AML in vitro and in vivo. Conclusions Inhibition of EZH2 by chidamide has antileukemia activity and increases the chemosensitivity to adriamycin through Smo/Gli-1 pathway in AML cells (Fig. 5). These findings support the rational combination of HDAC inhibitors and chemotherapy for the treatment of AML.

scholarly journals PS1452 GLI-1, EFFECTOR OF CANONICAL HEDGEHOG SIGNALING PATHWAY, DOES NOT SEEM TO BE DYSREGULATED IN PATIENTS WITH MYELOFIBROSIS

HemaSphere ◽  
2019 ◽  
Vol 3 (S1) ◽  
pp. 668
Author(s):  
M. Lucijanic ◽  
A. Livun ◽  
T. Stoos-Veic ◽  
V. Pejsa ◽  
Z. Jonjic ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
Hedgehog Signaling ◽  
Hedgehog Signaling Pathway ◽  
Gli 1

siRNA/lipopolymer nanoparticles to arrest growth of chronic myeloid leukemia cells in vitro and in vivo

2018 ◽  
Vol 130 ◽  
pp. 66-70 ◽  
Author(s):  
Juliana Valencia-Serna ◽  
Hamidreza M. Aliabadi ◽  
Adam Manfrin ◽  
Mahsa Mohseni ◽  
Xiaoyan Jiang ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Leukemia Cells ◽  
Arrest Growth

CREB Plays a Critical Role in the Regulation of Normal and Malignant Hematopoiesis.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1224-1224
Author(s):  
Jerry C. Cheng ◽  
Dejah Judelson ◽  
Kentaro Kinjo ◽  
Jenny Chang ◽  
Elliot Landaw ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Cell Proliferation ◽  
Progenitor Cells ◽  
Myeloid Leukemia ◽  
Bone Marrow Cells ◽  
Leukemia Cells ◽  
Mouse Bone Marrow ◽  
T315i Mutation

Abstract The cAMP Response Element Binding Protein, CREB, is a transcription factor that regulates cell proliferation, memory, and glucose metabolism. We previously demonstrated that CREB overexpression is associated with an increased risk of relapse in a small cohort of adult acute myeloid leukemia (AML) patients. Transgenic mice that overexpress CREB in myeloid cells develop myeloproliferative/myelodysplastic syndrome after one year. Bone marrow cells from these mice have increased self-renewal and proliferation. To study the expression of CREB in normal hematopoiesis, we performed quantitative real-time PCR in both mouse and human hematopoietic stem cells (HSCs). CREB expression was highest in the lineage negative population and was expressed in mouse HSCs, common myeloid progenitors, granulocyte/monocyte progenitors, megakaryocyte/erythroid progenitors, and in human CD34+38- cells. To understand the requirement of CREB in normal HSCs and myeloid leukemia cells, we inhibited CREB expression using RNA interference in vitro and in vivo. Bone marrow progenitor cells infected with CREB shRNA lentivirus demonstrated a 5-fold decrease in CFU-GM but increased Gr-1/Mac-1+ cells compared to vector control infected cells (p<0.05). There were fewer terminally differentiated Mac-1+ cells in the CREB shRNA transduced cells (30%) compared to vector control (50%), suggesting that CREB is critical for both myeloid cell proliferation and differentiation. CREB downregulation also resulted in increased apoptosis of mouse bone marrow progenitor cells. Given our in vitro results, we transplanted sublethally irradiated mice with mouse bone marrow cells transduced with CREB or scrambled shRNA. At 5 weeks post-transplant, we observed increased Gr-1+/Mac-1+ cells in mice infused with CREB shRNA transduced bone marrow compared to controls. After 12 weeks post-transplant, there was no difference in hematopoietic reconstitution or in the percentage of cells expressing Gr-1+, Mac-1+, Gr-1/Mac-1+, B22-+, CD3+, Ter119+, or HSCs markers, suggesting that CREB is not required for HSC engraftment. To study the effects of CREB knockdown in myeloid leukemia cells, K562 and TF-1 cells were infected with CREB shRNA lentivirus, sorted for GFP expression, and analyzed for CREB expression and proliferation. Within 72 hours, cells transduced with CREB shRNA demonstrated decreased proliferation and survival with increased apoptosis. In cell cycle experiments, we observed increased numbers of cells in G1 and G2/M with CREB downregulation. Expression of cyclins A1 and D, which are known target genes of CREB, was statistically significantly decreased in TF-1 and K562 cells transduced with CREB shRNA lentivirus compared to controls. To study the in vivo effects of CREB knockdown on leukemic progression, we injected SCID mice with Ba/F3 cells expressing bcr-abl or bcr-abl with the T315I mutation and the luciferase reporter gene. Cells were transduced with either CREB or scrambled shRNA. Disease progression was monitored using bioluminescence imaging. The median survival of mice injected with CREB shRNA transduced Ba/F3 bcr-abl or bcr-abl with the T315I mutation was increased with CREB downregulation compared to controls (p<0.05). Our results demonstrate that CREB is a critical regulator of normal and neoplastic hematopoiesis both in vitro and in vivo.

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