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1.
Rinsho Ketsueki ; 62(3): 180-185, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-33828011

RESUMO

We report the case of a 26-year-old male patient with chronic myelogenous leukemia in the chronic phase with the e13a3 (b2a3) variant of BCR-ABL1 fusion. Despite the presence of Philadelphia chromosome and fluorescence in situ hybridization-detectable BCR-ABL1 fusion signals, quantitative measurement of BCR-ABL1 on the ABL1 using a reverse primer in exon 2 of ABL1 failed to detect the fusion transcripts. PCR direct sequencing analysis with a sense primer for exon 13 of BCR and an antisense primer for exon 3 of ABL1 revealed the e13a3 variant of BCR-ABL1 fusion. The variant fusion transcript level was successfully monitored by the TaqMan assay using a forward primer and probe both in exon 13 of BCR and a reverse primer in exon 3 of ABL1. The patient responded extremely well to imatinib treatment, similar to previously reported e13a3 cases. The patient achieved a molecular response (undetectable e13a3 transcripts) after 12 months of treatment.


Assuntos
Proteínas de Fusão bcr-abl , Leucemia Mielogênica Crônica BCR-ABL Positiva , Adulto , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib/uso terapêutico , Hibridização in Situ Fluorescente , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Inibidores de Proteínas Quinases/uso terapêutico
2.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(3): 322-327, 2021 Mar 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33927081

RESUMO

Chronic myeloid leukemia with a significant increase of monocytes is rare and difficult to identify from chronic myelo-monocytic leukemia in clinic. A 31-year-old male patient with systemic pain was initially diagnosed as chronic myelo-monocytic leukemia, who was finally diagnosed as chronic myeloid leukemia by fusion gene and chromosome examination. In addition to the typical Ph chromosome, a rare chromosome translocation t(2; 7)(p13; p22) was observed. The detection of monocyte subsets by multi-parameter flow cytometry is a diagnostic marker to distinguish the above 2 diseases. The relationship between fusion genes and mononucleosis is not clear. Tyrosine kinase inhibitors or allogeneic hematopoietic stem cell transplantation can be used in the treatment for this disease.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Monócitos , Adulto , Humanos , Cariótipo , Cariotipagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Translocação Genética
3.
Zhonghua Xue Ye Xue Za Zhi ; 42(3): 224-229, 2021 Mar 14.
Artigo em Chinês | MEDLINE | ID: mdl-33910308

RESUMO

Objective: To explore the influence of storage and delivery conditions of the peripheral blood samples from patients with chronic myeloid leukemia (CML) on the real-time quantitative PCR (RQ-PCR) detection of the BCR-ABL (P210) transcript levels. Methods: The peripheral blood samples of 84 CML patients were collected. The same sample was divided into different groups according to storage time (0, 6, 12, 24, 48, and 72 h) , temperature (room temperature, 18-24 ℃; low temperature, 2-8 ℃) , and vibration conditions (3, 6, and 12 h) . RQ-PCR was used to detect BCR-ABL (P210) transcript levels of the different groups. This study logarithmically transformed (log(10N)) the original data [BCR-ABL copy number, ABL copy number, and BCR-ABL (P210) transcript levels]. Results: ①Agarose gel electrophoresis showed significant RNA degradation of samples after storage for 48 and 72 h at room temperature. ②Among the overall samples, the BCR-ABL copy number of the samples stored at room temperature for 48 and 72 h was significantly lower than that of the samples stored at low temperature (P<0.05) . However, the BCR-ABL (P210) transcript levels had no significant difference between samples stored at low temperature and room temperature. ③No significant changes were noted in the BCR-ABL (P210) transcript levels at different storage times (6, 12, 24, 48, and 72 h) regardless of storage temperature (P>0.05) compared with that at baseline (0 h, -0.56±1.51) . ④ The BCR-ABL copy number of the overall sample only decreased significantly (P<0.05) at 48 h (2.93±1.59) and 72 h (2.79±1.42) compared with that at baseline (0 h, 3.35±1.60) when stored at room temperature. The ABL copy number in the overall sample decreased significantly at 48 and 72 h (whether low and room temperature; P<0.05) . However, no significant changes were noted in the BCR-ABL (P210) transcript levels after vibration for 3 h (-1.29±1.81) , 6 h (-1.24±1.72) , and 12 h (-1.18±1.68; P>0.05) compared with that at baseline (0 h, -0.60±1.37) . Conclusion: Sample storage time, storage temperature, and vibration can interfere with the results of BCR-ABL and ABL copy number but have no significant effect on the quantitative determination of BCR-ABL (P210) transcript levels. This study provides strong support for the feasibility of transregional transportation of peripheral blood samples from patients with CML.


Assuntos
Proteínas de Fusão bcr-abl , Leucemia Mielogênica Crônica BCR-ABL Positiva , Proteínas de Fusão bcr-abl/genética , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Reação em Cadeia da Polimerase em Tempo Real
4.
Zhonghua Xue Ye Xue Za Zhi ; 42(3): 243-249, 2021 Mar 14.
Artigo em Chinês | MEDLINE | ID: mdl-33910311

RESUMO

Objective: To observe the effects of miR-21 knockout on proliferation and drug resistance in K562/G01 cells, and to preliminarily explore the mechanism of imatinib sensitivity by knocking out miR-21 in K562/G01 cells. Methods: Using CRISPR/Cas9 to knock out the miR-21 gene in K562/G01 cells, and single-cell-derived clones of miR-21 knockout were obtained by genomic DNA PCR screening, Sanger sequencing, and real-time PCR. We used MTT and cell colony formation assays to assess the cell proliferation, and determined imatinib sensitivity by MTT assay and Annexin-Ⅴ-APC/7-AAD double staining flow cytometry. Using western blot, we examined the potential mechanisms affecting imatinib sensitivity by knocking out miR-21 in K562/G01 cells. Results: Three miR-21 knockout K562/G01 single-cell-derived clones were successfully constructed. The mutation efficiency mediated by CRISPR/Cas9 was 7.12%-8.11%. MiR-21 knockout inhibited the proliferation of K562/G01 cells; the clone formation rates of WT and 1#, 2#, 6# K562/G01 single-cell clones were (57.67±8.25) %, (26.94± 5.36) %, (7.17±2.11) %, (31.50±3.65) %, respectively. MiR-21 knockout increased the sensitivity of K562/G01 cells to imatinib, IC(50) of imatinib in WT, and 1#, 2#, 6# K562/G01 single-cell clones were (21.92±1.36) µmol/ml, (3.98±0.39) µmol/ml, (5.38±1.01) µmol/ml, (9.24±1.36) µmol/ml. After the knockout of miR-21, the activation of PI3K/Akt signaling molecules was inhibited, while the expression of P210(B)CR-ABL and p-P210(BCR-ABL) was downregulated; however, the expression of PTEN was not affected. Conclusion: The knockout of miR-21 can suppress cell proliferation and improve sensitivity to imatinib in K562/G01 cells, which may be achieved by inhibiting the PI3K/AKT signaling pathway and BCR-ABL expression.


Assuntos
Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva , MicroRNAs , Antineoplásicos/farmacologia , Apoptose , Sistemas CRISPR-Cas , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib/farmacologia , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , MicroRNAs/genética , Fosfatidilinositol 3-Quinases
5.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807519

RESUMO

Chronic myeloid neoplasms are clonal diseases with variable clinical course and outcomes and despite the introduction of novel therapies, patients with high-risk disease continue to have overall poor outcomes. Different groups have highlighted that men have overall worse survival and higher incidence of transformation to acute leukemia compared to women across neoplasms such as myelodysplastic syndrome (MDS), myeloproliferative neoplasms (MPN), MDS/MPN overlap neoplasms, and CML. More recent studies evaluating the genomic profile of patients with these neoplasms demonstrated a male predominance for mutations in high-risk genes including ASXL1, U2AF1, SRSF2 and ZRSR2. The understanding of the underlying biology is limited but a number of hypotheses have been developed and are currently being investigated. This review summarizes the current knowledge about sex-related differences in the clinical outcomes and genomic profile of patients with chronic myeloid neoplasms and discusses the hypothesized biologic mechanisms as an attempt to explain these observations.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Animais , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Mutação/genética , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/patologia , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Caracteres Sexuais
6.
Nat Commun ; 12(1): 1065, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33594067

RESUMO

The production of blood cells during steady-state and increased demand depends on the regulation of hematopoietic stem cell (HSC) self-renewal and differentiation. Similarly, the balance between self-renewal and differentiation of leukemia stem cells (LSCs) is crucial in the pathogenesis of leukemia. Here, we document that the TNF receptor superfamily member lymphotoxin-ß receptor (LTßR) and its ligand LIGHT regulate quiescence and self-renewal of murine and human HSCs and LSCs. Cell-autonomous LIGHT/LTßR signaling on HSCs reduces cell cycling, promotes symmetric cell division and prevents primitive HSCs from exhaustion in serial re-transplantation experiments and genotoxic stress. LTßR deficiency reduces the numbers of LSCs and prolongs survival in a murine chronic myeloid leukemia (CML) model. Similarly, LIGHT/LTßR signaling in human G-CSF mobilized HSCs and human LSCs results in increased colony forming capacity in vitro. Thus, our results define LIGHT/LTßR signaling as an important pathway in the regulation of the self-renewal of HSCs and LSCs.


Assuntos
Diferenciação Celular , Autorrenovação Celular , Células-Tronco Hematopoéticas/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Receptor beta de Linfotoxina/metabolismo , Células-Tronco Neoplásicas/patologia , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Animais , Antígenos CD34/metabolismo , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Autorrenovação Celular/efeitos dos fármacos , Autorrenovação Celular/genética , Dano ao DNA , Fluoruracila/farmacologia , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Leuk Res ; 101: 106512, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33524640

RESUMO

BACKGROUND: Chronic Myeloid Leukemia (CML) is characterized by the overproduction of BCR-ABL, a tyrosine kinase with constitutive activity, in which the majority of CML patients have e13a2 or e14a2 transcripts. Reckoned the possible associations between the hematologic and molecular features of the disease, a profound understanding of different aspects of this neoplasm would be provided. METHOD: The authors implemented a systematic literature search, utilizing the terms published articles or internationally accepted abstracts from PubMed, Embase, Medline, Cochrane library before January 2019. Weighted mean proportion and 95 % confidence intervals (CIs) of CML prevalence calculated using a fixed-effects and a random-effects model. Statistical heterogeneity was evaluated using the I2 statistic. RESULTS: 34 studies for a total of 54,034 Patients were selected and included in the review. Results revealed that compared to e13a2 group, the overall estimated prevalence is much higher in the e14a2 (39 % and 54 %, respectively). Besides, the overall estimated prevalence ratio of male to female was higher in the e13a2 group in comparison to e14a2 (1.08 and 0.856 respectively). The overall estimated prevalence of dual transcription of e13a2/e14a2 was 1.11 %, and male/female overall estimated prevalence ratio was 1.18. CONCLUSION: This meta-analysis of CML patients demonstrated the e14a2 as the more common transcript type. Usually, the e14a2 transcript is prevalent in females, whereas e13a2 and dual transcription of e13a2/e14a2 are more common in men. These data explicate that the differences in proportion are not by chance. This is crucial, as the transcript type is a variable suspected to be of prognostic importance for the treatment-related response, the outcome of treatment, and the rate of treatment-free remission.


Assuntos
Proteínas de Fusão bcr-abl , Leucemia Mielogênica Crônica BCR-ABL Positiva , Feminino , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/epidemiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Prevalência , Prognóstico , Caracteres Sexuais
8.
Mol Pharmacol ; 99(3): 226-241, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33446509

RESUMO

An essential function of DNA topoisomerase IIα (TOP2α; 170 kDa, TOP2α/170) is to resolve DNA topologic entanglements during chromosome disjunction by introducing transient DNA double-stranded breaks. TOP2α/170 is an important target for DNA damage-stabilizing anticancer drugs, whose clinical efficacy is compromised by drug resistance often associated with decreased TOP2α/170 expression. We recently demonstrated that an etoposide-resistant K562 clonal subline, K/VP.5, with reduced levels of TOP2α/170, expresses high levels of a novel C-terminal truncated TOP2α isoform (90 kDa, TOP2α/90). TOP2α/90, the translation product of a TOP2α mRNA that retains a processed intron 19 (I19), heterodimerizes with TOP2α/170 and is a resistance determinant through a dominant-negative effect on drug activity. We hypothesized that genome editing to enhance I19 removal would provide a tractable strategy to circumvent acquired TOP2α-mediated drug resistance. To enhance I19 removal in K/VP.5 cells, CRISPR/Cas9 was used to make changes (GAG//GTAA AC →GAG//GTAA GT ) in the TOP2α gene's suboptimal exon 19/intron 19 5' splice site (E19/I19 5' SS). Gene-edited clones were identified by quantitative polymerase chain reaction and verified by sequencing. Characterization of a clone with all TOP2α alleles edited revealed improved I19 removal, decreased TOP2α/90 mRNA/protein, and increased TOP2α/170 mRNA/protein. Sensitivity to etoposide-induced DNA damage (γH2AX, Comet assays) and growth inhibition was restored to levels comparable to those in parental K562 cells. Together, the results indicate that our gene-editing strategy for optimizing the TOP2α E19/I19 5' SS in K/VP.5 cells circumvents resistance to etoposide and other TOP2α-targeted drugs. SIGNIFICANCE STATEMENT: Results presented here indicate that CRISPR/Cas9 gene editing of a suboptimal exon 19/intron 19 5' splice site in the DNA topoisomerase IIα (TOP2α) gene results in circumvention of acquired drug resistance to etoposide and other TOP2α-targeted drugs in a clonal K562 cell line by enhancing removal of intron 19 and thereby decreasing formation of a truncated TOP2α 90 kDa isoform and increasing expression of full-length TOP2α 170 kDa in these resistant cells. Results demonstrate the importance of RNA processing in acquired drug resistance to TOP2α-targeted drugs.


Assuntos
DNA Topoisomerases Tipo II/genética , Regulação para Baixo , Etoposídeo/farmacologia , Edição de Genes/métodos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proteínas de Ligação a Poli-ADP-Ribose/genética , Sistemas CRISPR-Cas , Sobrevivência Celular , Resistencia a Medicamentos Antineoplásicos , Humanos , Íntrons , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Sítios de Splice de RNA
9.
Nat Commun ; 12(1): 51, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397955

RESUMO

Identifying novel drug targets to overcome resistance to tyrosine kinase inhibitors (TKIs) and eradicating leukemia stem/progenitor cells are required for the treatment of chronic myelogenous leukemia (CML). Here, we show that ubiquitin-specific peptidase 47 (USP47) is a potential target to overcome TKI resistance. Functional analysis shows that USP47 knockdown represses proliferation of CML cells sensitive or resistant to imatinib in vitro and in vivo. The knockout of Usp47 significantly inhibits BCR-ABL and BCR-ABLT315I-induced CML in mice with the reduction of Lin-Sca1+c-Kit+ CML stem/progenitor cells. Mechanistic studies show that stabilizing Y-box binding protein 1 contributes to USP47-mediated DNA damage repair in CML cells. Inhibiting USP47 by P22077 exerts cytotoxicity to CML cells with or without TKI resistance in vitro and in vivo. Moreover, P22077 eliminates leukemia stem/progenitor cells in CML mice. Together, targeting USP47 is a promising strategy to overcome TKI resistance and eradicate leukemia stem/progenitor cells in CML.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Inibidores de Proteínas Quinases/farmacologia , Ubiquitina Tiolesterase/metabolismo , Proteases Específicas de Ubiquitina/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas de Fusão bcr-abl , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Camundongos Knockout , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais/efeitos dos fármacos , Tiofenos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína 1 de Ligação a Y-Box/metabolismo , Proteínas ras/metabolismo
10.
Anticancer Res ; 40(9): 5313-5317, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878823

RESUMO

BACKGROUND/AIM: Imatinib (IM) is the standard-of-care treatment for most chronic myeloid leukemia (CML) patients in chronic phase (CP). However, some patients suffer from low-grade side-effects that, in the long run, severely affect the quality of life and require treatment discontinuation due to toxicities. Fortunately, there are several therapeutic alternatives for these patients. Among them, the second-generation tyrosine kinase inhibitor dasatinib (DAS), used as second-line treatment, has shown to be a valid option in patients with CP-CML after intolerance to prior IM. PATIENTS AND METHODS: Herein, we report on seven CP-CML patients who achieved a stable major molecular response (MMR) with IM-therapy, but were shifted to DAS treatment due to recurrent low-grade IM-intolerances (grades 1-2). RESULTS AND CONCLUSION: All patients received conventional DAS treatment with a median daily dose of 83.3 mg. Treatment was well tolerated and side-effects were mild. In addition, after a median follow-up of 25 months (range=24-43 months) a deep molecular response (DMR) (either MR4 or MR4.5) was achieved in all patients after 24 months of treatment. This finding, although limited to a small cohort of CP-CML patients, supports the view that a therapy switch from IM to DAS induces a reduction of symptom burden, improves patient compliance and shows clinical efficacy in achieving and sustaining deep molecular responses.


Assuntos
Antineoplásicos/uso terapêutico , Dasatinibe/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Cooperação do Paciente , Inibidores de Proteínas Quinases/uso terapêutico , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Dasatinibe/administração & dosagem , Dasatinibe/efeitos adversos , Feminino , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib/efeitos adversos , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Pessoa de Meia-Idade , Mutação , Gradação de Tumores , Inibidores de Proteínas Quinases/administração & dosagem , Inibidores de Proteínas Quinases/efeitos adversos , Retratamento , Resultado do Tratamento
11.
Vnitr Lek ; 66(4): 214-224, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32972178

RESUMO

Chronic myeloid leukemia (CML) is a clonal myeloproliferative neoplasia that is characterised by Philadelphia chromosome (Ph1 chromosome) and/or fusion gene BCR-ABL1 in bone marrow. Interpheron α and bone marrow transplantation used to be the main treatment modalities for patients with CML 20 years ago. Due to the introduction of imatinib mesylate since the year 2000 the outcome of CML patients has dramatically improved. The survival of both younger and elderly patients in the case of an optimal response has been prolonged and currently is close to survival of healthy population. Although, one third of patients does not respond well to first line imatinib and needs to change the treatment to second line tyrosine kinase inhibitors (TKI: bosutinib, dasatinib and nilotinib). Younger patients without cardiologic and metabolic disorders and those with poor risk profile score may have benefit from TKI of 2nd generation as a 1st line treatment option with the aim of reaching deeper molecular response and the chance of treatment free remission (TFR) in future. By older patients with severe comorbidities and in patients with good risk profile score imatinib as a 1st line treatment option can be used. For patients who are resistant simultaneously to 2nd generation TKI and for patients with mutation T315I ponatinib - TKI of 3rd generation can be used effectively. Intolerance and toxicity of TKI´s are the main barriers of effective CML treatment. TKI selection for each patient should be individual. Patient´s cooperation with medical team is crucial and inevitable in long time treatment process. The chance for TFR has become feasible for approximately 40-60 % CML patients in deep and durable molecular remission and represents a further important milestone in the management of CML patients.


Assuntos
Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Adulto , Idoso , Antineoplásicos/uso terapêutico , Dasatinibe/uso terapêutico , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/uso terapêutico , Humanos , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Inibidores de Proteínas Quinases/uso terapêutico
12.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(7): 874-880, 2020 Jul 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32879093

RESUMO

Chronic myeloid leukemia (CML) is one of the most common hematological malignancies and characterized by the formation of Philadelphia (Ph) chromosome. Recently, tyrosine kinase inhibitors (TKI) treatment greatly improved the prognosis of CML. However, the options may be limited when a patient develops traditional TKI resistance or gene mutation. Herein, we reported a case. A 38-year-old male CML patient developed a BCR-ABL1 gene mutation of T315I after 2.5 years of TKI treatment, including imatinib and dasatinib. We adjusted the treatment with the combined application of dasatinib and axitinib. BCR-ABL1 gene copies dropped down and achieved an early molecular response at 2 months later. Subsequently, he received hematopoietic stem cell transplantation. Axitinib and dasatinib were applied for another half year after the allogeneic hematopoietic stem cell transplantation (allo-HSCT). Two years after the allo-HSCT, the BCR-ABL1 gene was still undetectable. It provided a successful example in treating CML patients carrying BCR-ABL1 T315I mutation via combination of axitinib with conditional TKI.


Assuntos
Axitinibe , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Adulto , Dasatinibe/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Masculino , Mutação , Inibidores de Proteínas Quinases/uso terapêutico
13.
Nucleic Acids Res ; 48(17): 9521-9537, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32766783

RESUMO

Hippuristanol (Hipp) is a natural product that selectively inhibits protein synthesis by targeting eukaryotic initiation factor (eIF) 4A, a DEAD-box RNA helicase required for ribosome recruitment to mRNA templates. Hipp binds to the carboxyl-terminal domain of eIF4A, locks it in a closed conformation, and inhibits its RNA binding. The dependencies of mRNAs for eIF4A during initiation is contingent on the degree of secondary structure within their 5' leader region. Interest in targeting eIF4A therapeutically in cancer and viral-infected settings stems from the dependencies that certain cellular (e.g. pro-oncogenic, pro-survival) and viral mRNAs show towards eIF4A. Using a CRISPR/Cas9-based variomics screen, we identify functional EIF4A1 Hipp-resistant alleles, which in turn allowed us to link the translation-inhibitory and cytotoxic properties of Hipp to eIF4A1 target engagement. Genome-wide translational profiling in the absence or presence of Hipp were undertaken and our validation studies provided insight into the structure-activity relationships of eIF4A-dependent mRNAs. We find that mRNA 5' leader length, overall secondary structure and cytosine content are defining features of Hipp-dependent mRNAs.


Assuntos
Regiões 5' não Traduzidas , Resistencia a Medicamentos Antineoplásicos/genética , Fator de Iniciação 4A em Eucariotos/genética , Esteróis/farmacologia , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fator de Iniciação 4A em Eucariotos/antagonistas & inibidores , Fator de Iniciação 4A em Eucariotos/metabolismo , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Mutação , Ribossomos/genética , Ribossomos/metabolismo
15.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(4): 1115-1122, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32798385

RESUMO

OBJECTIVE: To analyze the significance of various abnormal signal patterns appreared in CML and B-ALL patients by using BCR/ABL/ASS1 tricolor dual-fusion probe, and to explore its application value in detecting BCR/ABL fusion gene and ASS1 gene deletion. METHODS: 50 newly diagnosed CML patients and 50 newly diagnosed B-ALL patients were detected by fluorescence in situ hybridization (FISH) with BCR/ABL/ASS1 tricolor dual-fusion probe. Meanwhile, karyotype analysis was performed on all the patients using the 24 hours short-term culture and R-banding. RESULTS: Among the 50 CML patients, Ph+ was found in 49 cases, 5 normal interphase karyotype was observed in 1 case. FISH detection showed that BCR/ABL fusion gene existed in all patients (100%), while the positive signal pathway showed that 1R1G2B2F was observed in 39 cases (78%), 2R1G2B1F in 2 cases (4%) and 1R1G2B1F in 6 cases (12%), simultaneous existence of 1R1G1B1F and 1R1G2B3F in 1 case (2%), 2R1G1B1F in 1 case (2%) 1R1G3B3F in 1 case (2%). FISH detection also showed that the karyotype of 6 case at ASS1 gene deletion (1R1G1B1F) all were simple t (9; 22) translocation, and other abnormalities not were observed. Among 50 cases of B-ALL, Ph+ was found in 13 cases, the numerical aberration and structural aberration of non t (9; 22) in 16 cases, normal karyotype in 20 cases, absence of mitotic phase in 1 case. FISH detection showed that 16 cases (32%) had BCR/ABL fusion gene including 13 cases (26%) of 1R1G2B2F, 1 case (2%) of stimultaneous exitance of 1R1G2B2F and 1R1G3B3F 1 case (2%) of 2R1G1B1F, 1 case (2%) of 1R1G3B2F. FISH detection also showed that 3 cases had BCR/ABL fusion gene, including 1 case with ASS1 gene deletion (2R1G1B1F), 1 case with classical t (9; 22) translocation (1R1G2B2F) and 1 case with BCR/ABL fusion gene and increase of ASS1 gene copy (1R1G3B3F). CONCLUSION: Tricolor dual-fusion FISH probe for detecting BCR/ABL fusion gene and ASS1 gene deletion is simple, rapid, sensitive and stable. It can detect various forms of molecular fusion and avoid the false positive results due to coincidental overlap of signals generated by D-FISH probe and ES-FISH probe. In addition, this detection method not only can directly observe the presence or absence of ASS1 gene deletion, but also improve the reliability of the positive results of newly diagnosed BCR/ABL fusion gene and accuracy of monitoring results of minimal residual disease for the subsequent visit.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proteínas de Fusão bcr-abl/genética , Deleção de Genes , Humanos , Hibridização in Situ Fluorescente , Reprodutibilidade dos Testes
17.
Hum Cell ; 33(4): 1112-1119, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32862368

RESUMO

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm. INNO-406 is a novel tyrosine kinase inhibitor (TKI) that possess specific Lyn kinase inhibitory activity with no or limited activity against other sarcoma (Src) family member kinases. The present study aimed to confirm the anti-tumor effect of INNO-406 on CML cells, and elucidate the underlying molecular mechanism. CML cells were treated by INNO-406 at the concentration of 5, 25, 50, 100 µM at the indicated time. Cell proliferation was measured by MTT. Cell apoptosis were detected by Western blot and flow cytometry, respectively. As suggested by the findings, INNO-406 significantly inhibited the proliferation and induced apoptosis of CML cells. In addition, INNO-406 promoted the expression level of PTEN. Rescue experiment revealed that PTEN knockdown reversed the effect of INNO-406 which indicated the correlation between INNO-406 and PTEN. Further study determined that PTEN inhibited the phosphorylation of AKT and 4EBP1 and subsequently altered the expression of apoptotic proteins including bax, cytoplasmic cytochrome c (cyto-c), cleaved caspase3 and bcl-2. In vivo study further confirmed that INNO-406 inhibited the growth of CML cells by targeting PTEN. Based on the above findings, this work extended our understanding of INNO-406 in the therapy of CML and its molecular mechanism.


Assuntos
Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Antineoplásicos , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Humanos
18.
Zhonghua Xue Ye Xue Za Zhi ; 41(6): 469-476, 2020 Jun 14.
Artigo em Chinês | MEDLINE | ID: mdl-32654459

RESUMO

Objectives: To explore BCR-ABL kinase domain mutation profiles and clinical variables associated with them in tyrosine kinase inhibitor (TKI) -resistant patients with chronic myeloid leukemia (CML) . Methods: Imatinib-, nilotinib-, and/or dasatinib-resistant patients with CML who screened BCR-ABL mutation (s) in Peking University People's Hospital between June 2001 and September 2019 were retrospectively reviewed. BCR-ABL mutation was analyzed by Sanger sequencing. Binary logistic regression model was built to identify independent clinical variables associated with developing BCR-ABL mutation (s) . Results: Data of 1 093 TKI-resistant cases in 804 patients who experienced resistance to imatinib (n=576, 52.7%) , nilotinib (n=238, 21.8%) , and dasatinib (n=279, 25.5%) were analyzed. In total, 291 (50.5%) imatinib-, 152 (63.9%) nilotinib-, and 160 (57.3%) dasatinib-resistant cases developed BCR-ABL mutation (s) . T315I mutation was the most frequent mutation detected in imatinib-, nilotinib-, and dasatinib-resistant cases, accounting for 12.3%, 27.3%, and 34.1%, respectively. Y253F/H (7.5%) and F359V/C/I (5.6%) were the mutation detected in ≥5% imatinib-resistant cases; F359V/C/I (12.2%) , Y253F/H (11.8%) , and E255K/V (10.5%) in nilotinib-resistant cases; and F317L/V/I/C (11.5%) and E255K/V (5.4%) in dasatinib-resistant cases. In multivariate analyses, no TKI dose reduction or discontinuation of TKI therapy was the common variable associated with developing BCR-ABL mutation (s) . Other variables associated with developing BCR-ABL mutation (s) in imatinib-, nilotinib-, or dasatinib-resistant cases included male gender, younger age, no comorbidity, advanced phase before starting current TKI therapy, longer interval from diagnosis to starting current TKI therapy, acquired resistance, and TKI resistance due to progression to advanced phase or hematologic failure. In addition, interval from TKI failure to BCR-ABL mutation detection, starting initial TKI therapy to TKI failure, and starting current TKI therapy to TKI failure were associated with the frequency of developing BCR-ABL mutation. Dasatinib and nilotinib use and acquired resistance were identified to be associated with the development of T315I mutation in multivariate analyses. Conclusions: More than half of TKI-resistant CML patients developed BCR-ABL mutation (s) by Sanger sequencing. T315I mutation was the most frequently detected. Clinical variables significantly associated with developing BCR-ABL mutation (s) should be used not only as basis for the choice of subsequent TKIs but also the understanding of TKI-resistant mechanisms.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Proteínas de Fusão bcr-abl , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Masculino , Mutação , Inibidores de Proteínas Quinases , Estudos Retrospectivos
19.
BMC Bioinformatics ; 21(1): 281, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32615918

RESUMO

BACKGROUND: During transcription, numerous transcription factors (TFs) bind to targets in a highly coordinated manner to control the gene expression. Alterations in groups of TF-binding profiles (i.e. "co-binding changes") can affect the co-regulating associations between TFs (i.e. "rewiring the co-regulator network"). This, in turn, can potentially drive downstream expression changes, phenotypic variation, and even disease. However, quantification of co-regulatory network rewiring has not been comprehensively studied. RESULTS: To address this, we propose DiNeR, a computational method to directly construct a differential TF co-regulation network from paired disease-to-normal ChIP-seq data. Specifically, DiNeR uses a graphical model to capture the gained and lost edges in the co-regulation network. Then, it adopts a stability-based, sparsity-tuning criterion -- by sub-sampling the complete binding profiles to remove spurious edges -- to report only significant co-regulation alterations. Finally, DiNeR highlights hubs in the resultant differential network as key TFs associated with disease. We assembled genome-wide binding profiles of 104 TFs in the K562 and GM12878 cell lines, which loosely model the transition between normal and cancerous states in chronic myeloid leukemia (CML). In total, we identified 351 significantly altered TF co-regulation pairs. In particular, we found that the co-binding of the tumor suppressor BRCA1 and RNA polymerase II, a well-known transcriptional pair in healthy cells, was disrupted in tumors. Thus, DiNeR successfully extracted hub regulators and discovered well-known risk genes. CONCLUSIONS: Our method DiNeR makes it possible to quantify changes in co-regulatory networks and identify alterations to TF co-binding patterns, highlighting key disease regulators. Our method DiNeR makes it possible to quantify changes in co-regulatory networks and identify alterations to TF co-binding patterns, highlighting key disease regulators.


Assuntos
Redes Reguladoras de Genes , Modelos Genéticos , Software , Imunoprecipitação da Cromatina , Regulação da Expressão Gênica , Genoma , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Ligação Proteica , Fatores de Transcrição/metabolismo , Transcrição Genética
20.
Hematol Oncol ; 38(4): 607-610, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32602167
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