Association of high-level MCL-1 expression with in vitro and in vivo prednisone resistance in MLL-rearranged infant acute lymphoblastic leukemia

Blood ◽  
2010 ◽  
Vol 115 (5) ◽  
pp. 1018-1025 ◽  
Author(s):  
Ronald W. Stam ◽  
Monique L. Den Boer ◽  
Pauline Schneider ◽  
Jasper de Boer ◽  
Jill Hagelstein ◽  
...  

Abstract MLL-rearranged acute lymphoblastic leukemia (ALL) represents an unfavorable type of leukemia that often is highly resistant to glucocorticoids such as prednisone and dexamethasone. Because response to prednisone largely determines clinical outcome of pediatric patients with ALL, overcoming resistance to this drug may be an important step toward improving prognosis. Here, we show how gene expression profiling identifies high-level MCL-1 expression to be associated with prednisolone resistance in MLL-rearranged infant ALL, as well as in more favorable types of childhood ALL. To validate this observation, we determined MCL-1 expression with quantitative reverse transcription–polymerase chain reaction in a cohort of MLL-rearranged infant ALL and pediatric noninfant ALL samples and confirmed that high-level MCL-1 expression is associated with prednisolone resistance in vitro. In addition, MCL-1 expression appeared to be significantly higher in MLL-rearranged infant patients who showed a poor response to prednisone in vivo compared with prednisone good responders. Finally, down-regulation of MCL-1 in prednisolone-resistant MLL-rearranged leukemia cells by RNA interference, to some extent, led to prednisolone sensitization. Collectively, our findings suggest a potential role for MCL-1 in glucocorticoid resistance in MLL-rearranged infant ALL, but at the same time strongly imply that high-level MCL-1 expression is not the sole mechanism providing resistance to these drugs.

Blood ◽  
1996 ◽  
Vol 88 (11) ◽  
pp. 4252-4258 ◽  
Author(s):  
TW McLean ◽  
S Ringold ◽  
D Neuberg ◽  
K Stegmaier ◽  
R Tantravahi ◽  
...  

Abstract Polymerase chain reaction-based screening of childhood acute lymphoblastic leukemia (ALL) samples showed that a TEL/AML1 fusion transcript was detected in 27% of all cases, representing the most common known gene rearrangement in childhood cancer. The TEL/AML1 fusion results from a t(12;21)(p13;q22) chromosomal translocation, but was undetectable at the routine cytogenetic level. TEL/AML1-positive patients had exclusively B-lineage ALL, and most patients were between the ages of 2 and 9 years at diagnosis. Only 3/89 (3.4%) adult ALL patients were TEL/AML1-positive. Most importantly, TEL/AML1-positive children had a significantly lower rate of relapse compared with TEL/AML1-negative patients (0/22 v 16/54, P = .004). Co- immunoprecipitation experiments demonstrated that TEL/AML-1 formed homodimers in vitro, and heterodimerized with the normal TEL protein when the two proteins were expressed together. The elucidation of the precise mechanism of transformation by TEL/AML1 and the role of TEL/AML1 testing in the treatment of childhood ALL will require additional studies.


Blood ◽  
1996 ◽  
Vol 88 (11) ◽  
pp. 4252-4258 ◽  
Author(s):  
TW McLean ◽  
S Ringold ◽  
D Neuberg ◽  
K Stegmaier ◽  
R Tantravahi ◽  
...  

Polymerase chain reaction-based screening of childhood acute lymphoblastic leukemia (ALL) samples showed that a TEL/AML1 fusion transcript was detected in 27% of all cases, representing the most common known gene rearrangement in childhood cancer. The TEL/AML1 fusion results from a t(12;21)(p13;q22) chromosomal translocation, but was undetectable at the routine cytogenetic level. TEL/AML1-positive patients had exclusively B-lineage ALL, and most patients were between the ages of 2 and 9 years at diagnosis. Only 3/89 (3.4%) adult ALL patients were TEL/AML1-positive. Most importantly, TEL/AML1-positive children had a significantly lower rate of relapse compared with TEL/AML1-negative patients (0/22 v 16/54, P = .004). Co- immunoprecipitation experiments demonstrated that TEL/AML-1 formed homodimers in vitro, and heterodimerized with the normal TEL protein when the two proteins were expressed together. The elucidation of the precise mechanism of transformation by TEL/AML1 and the role of TEL/AML1 testing in the treatment of childhood ALL will require additional studies.


2021 ◽  
Vol 5 (18) ◽  
pp. 3633-3646
Author(s):  
Leonardo Luís Artico ◽  
Angelo Brunelli Albertoni Laranjeira ◽  
Livia Weijenborg Campos ◽  
Juliana Ronchi Corrêa ◽  
Priscila Pini Zenatti ◽  
...  

Abstract Insulin and insulin-like growth factors (IGFs) are mitogenic and prosurvival factors to many different cell types, including acute lymphoblastic leukemia (ALL). Circulating IGFs are bound by IGF binding proteins (IGFBPs) that regulate their action. IGFBP7 is an IGFBP-related protein (IGFBP-rP) that in contrast to other IGFBPs/IGFBP-rPs features higher affinity for insulin than IGFs and was shown to bind the IGF1 receptor (IGF1R) as well. The role of IGFBP7 in cancer is controversial: on some tumors, it functions as an oncogene, whereas in others, it functions as a tumor suppressor. In childhood ALL, higher IGFBP7 expression levels were associated with worse prognosis. Here we show that IGFBP7 exerts mitogenic and prosurvival autocrine effects on ALL cells that were dependent on insulin/IGF. IGFBP7 knockdown or antibody-mediated neutralization resulted in significant attenuation of ALL cell viability in vitro and leukemia progression in vivo. IGFBP7 was shown to prolong the surface retention of the IGF1R under insulin/IGF1 stimulation, resulting in sustained IGF1R, insulin receptor substrate 1 (IRS-1), protein kinase B (AKT), and extracellular signal-regulated kinase (ERK) phosphorylation. Conversely, the insulin receptor was readily internalized and dephosphorylated on insulin stimulation, despite IGFBP7 addition. The affinity of homodimeric IGF1R for insulin is reportedly >100 times lower than for IGF1. In the presence of IGFBP7, however, 25 ng/mL insulin resulted in IGF1R activation levels equivalent to that of 5 ng/mL IGF1. In conclusion, IGFBP7 plays an oncogenic role in ALL by promoting the perdurance of IGF1R at the cell surface, prolonging insulin/IGF stimulation. Preclinical data demonstrate that IGFBP7 is a valid target for antibody-based therapeutic interventions in ALL.


Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 148-148 ◽  
Author(s):  
Tillmann Taube ◽  
Shabnam Shalapour ◽  
Georg J. Seifert ◽  
Madlen Pfau ◽  
Guenter Henze ◽  
...  

Abstract The BCR-ABL fusion protein p190 resulting from the translocation t(9;22) exhibits dysregulated tyrosine kinase activity and was shown to cause acute lymphoblastic leukemia (ALL). Detection of the BCR-ABL fusion gene in childhood ALL is associated with an adverse prognosis and defines a group of high risk patients. Because the BCR-ABL gene fusion is specific for leukemic cells it represents an ideal target for leukemia specific treatment approaches. Catalytic DNAzymes are able to cleave mRNA in a sequence specific manner, causing inhibition of protein translation from the DNAzyme targeted mRNA both in vitro and in vivo. In order to cut off the BCR-ABL driven malignant proliferation, we designed DNAzymes to impede the expression of p190 BCR-ABL by cleaving the BCR-ABL mRNA adjacent to the fusion site. One construct was found that cleaved the target mRNA efficiently and specifically leaving BCR and ABL, relevant for normal cell survival and proliferation, unaffected. Activity and specificity of the BCR-ABL DNAzyme was investigated in cleavage assays with in vitro transcribed BCR-ABL, BCR and ABL mRNA. DNAzymes were delivered to cultured BCR-ABL+ ALL cells by lipid transfection. The efficiency of cellular delivery reached 90% as studied by flow cytometry, fluorescence microscopy and confocal microscopy after transfection of FITC labeled DNAzymes. To control for unspecific effects of DNAzyme delivery as well as for antisense effects, a catalytically inactive DNAzyme still exhibiting BCR-ABL antisense activity was designed. Fourty-eight hours after a single treatment of BCR-ABL+ ALL-cells with DNAyzmes the BCR-ABL mRNA concentration, as measured by quantitative real-time RT-PCR, was significantly reduced by 56% and 66% compared to controls treated with the inactivated DNAzyme and to untreated cells, respectively. Western blot analysis showed a decrease in p190 protein levels after DNAzyme treatment in comparison to the control treated with inactive DNAzyme as well as to the untreated cells. Most noteworthy, four days after a single DNAzyme treatment the net growth of BCR-ABL+ ALL cells treated with the active DNAzyme was inhibited by 68% compared to the untreated control. From these data we conclude, firstly, DNAzymes targeting mRNA coding for the minor BCR-ABL variant are able to significantly reduce the amount of fusion mRNA in the cells, leading to a reduction in protein expression, followed by the inhibition of BCR-ABL driven proliferation of ALL cells. Secondly, this exemplified setting gives a hint that DNAzymes might be of therapeutic use in hematopoietic malignancies associated with specific mutations, expressing oncogenic fusion genes or overexpressing oncogenic genes.


Blood ◽  
2004 ◽  
Vol 103 (10) ◽  
pp. 3905-3914 ◽  
Author(s):  
Natalia L. M. Liem ◽  
Rachael A. Papa ◽  
Christopher G. Milross ◽  
Michael A. Schmid ◽  
Mayamin Tajbakhsh ◽  
...  

Abstract Continuous xenografts from 10 children with acute lymphoblastic leukemia (ALL) were established in nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. Relative to primary engrafted cells, negligible changes in growth rates and immunophenotype were observed at second and third passage. Analysis of clonal antigen receptor gene rearrangements in 2 xenografts from patients at diagnosis showed that the pattern of clonal variation observed following tertiary transplantation in mice exactly reflected that in bone marrow samples at the time of clinical relapse. Patients experienced diverse treatment outcomes, including 5 who died of disease (median, 13 months; range, 11-76 months, from date of diagnosis), and 5 who remain alive (median, 103 months; range, 56-131 months, following diagnosis). When stratified according to patient outcome, the in vivo sensitivity of xenografts to vincristine and dexamethasone, but not methotrexate, differed significantly (P = .028, P = .029, and P = .56, respectively). The in vitro sensitivity of xenografts to dexamethasone, but not vincristine, correlated significantly with in vivo responses and patient outcome. This study shows, for the first time, that the biologic and genetic characteristics, and patterns of chemosensitivity, of childhood ALL xenografts accurately reflect the clinical disease. As such, they provide powerful experimental models to prioritize new therapeutic strategies for future clinical trials.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Shuiyan Wu ◽  
You Jiang ◽  
Yi Hong ◽  
Xinran Chu ◽  
Zimu Zhang ◽  
...  

Abstract Background T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive disease with a high risk of induction failure and poor outcomes, with relapse due to drug resistance. Recent studies show that bromodomains and extra-terminal (BET) protein inhibitors are promising anti-cancer agents. ARV-825, comprising a BET inhibitor conjugated with cereblon ligand, was recently developed to attenuate the growth of multiple tumors in vitro and in vivo. However, the functional and molecular mechanisms of ARV-825 in T-ALL remain unclear. This study aimed to investigate the therapeutic efficacy and potential mechanism of ARV-825 in T-ALL. Methods Expression of the BRD4 were determined in pediatric T-ALL samples and differential gene expression after ARV-825 treatment was explored by RNA-seq and quantitative reverse transcription-polymerase chain reaction. T-ALL cell viability was measured by CCK8 assay after ARV-825 administration. Cell cycle was analyzed by propidium iodide (PI) staining and apoptosis was assessed by Annexin V/PI staining. BRD4, BRD3 and BRD2 proteins were detected by western blot in cells treated with ARV-825. The effect of ARV-825 on T-ALL cells was analyzed in vivo. The functional and molecular pathways involved in ARV-825 treatment of T-ALL were verified by western blot and chromatin immunoprecipitation (ChIP). Results BRD4 expression was higher in pediatric T-ALL samples compared with T-cells from healthy donors. High BRD4 expression indicated a poor outcome. ARV-825 suppressed cell proliferation in vitro by arresting the cell cycle and inducing apoptosis, with elevated poly-ADP ribose polymerase and cleaved caspase 3. BRD4, BRD3, and BRD2 were degraded in line with reduced cereblon expression in T-ALL cells. ARV-825 had a lower IC50 in T-ALL cells compared with JQ1, dBET1 and OTX015. ARV-825 perturbed the H3K27Ac-Myc pathway and reduced c-Myc protein levels in T-ALL cells according to RNA-seq and ChIP. In the T-ALL xenograft model, ARV-825 significantly reduced tumor growth and led to the dysregulation of Ki67 and cleaved caspase 3. Moreover, ARV-825 inhibited cell proliferation by depleting BET and c-Myc proteins in vitro and in vivo. Conclusions BRD4 indicates a poor prognosis in T-ALL. The BRD4 degrader ARV-825 can effectively suppress the proliferation and promote apoptosis of T-ALL cells via BET protein depletion and c-Myc inhibition, thus providing a new strategy for the treatment of T-ALL.


2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Ilaria Iacobucci ◽  
Andrea Ghelli Luserna Di Rorà ◽  
Maria Vittoria Verga Falzacappa ◽  
Claudio Agostinelli ◽  
Enrico Derenzini ◽  
...  

Cells ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1726
Author(s):  
Valentina Saccomani ◽  
Angela Grassi ◽  
Erich Piovan ◽  
Deborah Bongiovanni ◽  
Ludovica Di Martino ◽  
...  

T-cell acute lymphoblastic leukemia (T-ALL) is a rare, aggressive disease arising from T-cell precursors. NOTCH1 plays an important role both in T-cell development and leukemia progression, and more than 60% of human T-ALLs harbor mutations in components of the NOTCH1 signaling pathway, leading to deregulated cell growth and contributing to cell transformation. Besides multiple NOTCH1 target genes, microRNAs have also been shown to regulate T-ALL initiation and progression. Using an established mouse model of T-ALL induced by NOTCH1 activation, we identified several microRNAs downstream of NOTCH1 activation. In particular, we found that NOTCH1 inhibition can induce miR-22-3p in NOTCH1-dependent tumors and that this regulation is also conserved in human samples. Importantly, miR-22-3p overexpression in T-ALL cells can inhibit colony formation in vitro and leukemia progression in vivo. In addition, miR-22-3p was found to be downregulated in T-ALL specimens, both T-ALL cell lines and primary samples, relative to immature T-cells. Our results suggest that miR-22-3p is a functionally relevant microRNA in T-ALL whose modulation can be exploited for therapeutic purposes to inhibit T-ALL progression.


Blood ◽  
2019 ◽  
Vol 133 (21) ◽  
pp. 2291-2304 ◽  
Author(s):  
Diego Sánchez-Martínez ◽  
Matteo L. Baroni ◽  
Francisco Gutierrez-Agüera ◽  
Heleia Roca-Ho ◽  
Oscar Blanch-Lombarte ◽  
...  

Abstract Relapsed/refractory T-cell acute lymphoblastic leukemia (T-ALL) has a dismal outcome, and no effective targeted immunotherapies for T-ALL exist. The extension of chimeric antigen receptor (CAR) T cells (CARTs) to T-ALL remains challenging because the shared expression of target antigens between CARTs and T-ALL blasts leads to CART fratricide. CD1a is exclusively expressed in cortical T-ALL (coT-ALL), a major subset of T-ALL, and retained at relapse. This article reports that the expression of CD1a is mainly restricted to developing cortical thymocytes, and neither CD34+ progenitors nor T cells express CD1a during ontogeny, confining the risk of on-target/off-tumor toxicity. We thus developed and preclinically validated a CD1a-specific CAR with robust and specific cytotoxicity in vitro and antileukemic activity in vivo in xenograft models of coT-ALL, using both cell lines and coT-ALL patient–derived primary blasts. CD1a-CARTs are fratricide resistant, persist long term in vivo (retaining antileukemic activity in re-challenge experiments), and respond to viral antigens. Our data support the therapeutic and safe use of fratricide-resistant CD1a-CARTs for relapsed/refractory coT-ALL.


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