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1.
J Mol Med (Berl) ; 102(3): 415-433, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38340163

RESUMO

Previous evidence has confirmed that branched-chain aminotransferase-1 (BCAT1), a key enzyme governing branched-chain amino acid (BCAA) metabolism, has a role in cancer aggression partly by restricting αKG levels and inhibiting the activities of the αKG-dependent enzyme family. The oncogenic role of BCAT1, however, was not fully elucidated in acute myeloid leukemia (AML). In this study, we investigated the clinical significance and biological insight of BCAT1 in AML. Using q-PCR, we analyzed BCAT1 mRNAs in bone marrow samples from 332 patients with newly diagnosed AML. High BCAT1 expression independently predicts poor prognosis in patients with AML. We also established BCAT1 knockout (KO)/over-expressing (OE) AML cell lines to explore the underlying mechanisms. We found that BCAT1 affects cell proliferation and modulates cell cycle, cell apoptosis, and DNA damage/repair process. Additionally, we demonstrated that BCAT1 regulates histone methylation by reducing intracellular αKG levels in AML cells. Moreover, high expression of BCAT1 enhances the sensitivity of AML cells to the Poly (ADP-ribose) polymerase (PARP) inhibitor both in vivo and in vitro. Our study has demonstrated that BCAT1 expression can serve as a reliable predictor for AML patients, and PARP inhibitor BMN673 can be used as an effective treatment strategy for patients with high BCAT1 expression. KEY MESSAGES: High expression of BCAT1 is an independent risk factor for poor prognosis in patients with CN-AML. High BCAT1 expression in AML limits intracellular αKG levels, impairs αKG-dependent histone demethylase activity, and upregulates H3K9me3 levels. H3K9me3 inhibits ATM expression and blocks cellular DNA damage repair process. Increased sensitivity of BCAT1 high expression AML to PARP inhibitors may be used as an effective treatment strategy in AML patients.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Humanos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Antineoplásicos/farmacologia , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Reparo do DNA , Dano ao DNA , Transaminases/genética
2.
Br J Haematol ; 202(6): 1119-1126, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37434414

RESUMO

To reducing chemotherapy-related toxicity, the chemo-free regimens become a new trend of Ph + ALL treatment. Therefore, we conducted a phase 2 trial of dasatinib plus prednisone, as induction (Course I) and early consolidation (Courses II and III) treating newly diagnosed Ph + ALL. The trial was registered at www.chictr.org.cn, ChiCTR2000038053. Forty-one patients were enrolled from 15 hospitals. The complete remission (CR) was 95% (39/41), including two elderly induction deaths. By the end of Course III, 25.6% (10/39) of patients achieved a complete molecular response. With a median follow-up of 15.4 months, 2-year disease-free survival (DFS) were 100% and 33% for patients who receiving haematopoietic stem cell transplantation (HSCT) at CR1 and receiving chemotherapy alone respectively. When censored at time of HSCT, 2-year DFS were 51% and 45% for young and elderly patients (p = 0.987). 2-year overall survival were 45%, 86% and 100% for patients without HSCT, receiving HSCT after relapse and receiving HSCT at CR1 respectively. A total of 12 patients had marrow recurrences and one had CNS relapse, with 38% occurred early (between Courses I and III). IKZF1 gene deletion was shown to be associated with relapse (p = 0.019). This chemo-free induction and early consolidation regimen was efficacious and well-tolerated in de novo Ph + ALL. Allogeneic HSCT conferred definite survival advantage after chemo-free induction.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Adulto , Idoso , Dasatinibe/efeitos adversos , Prednisona/efeitos adversos , Cromossomo Filadélfia , Recidiva Local de Neoplasia/tratamento farmacológico , Intervalo Livre de Doença , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Indução de Remissão , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
3.
Front Med ; 17(4): 685-698, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37131085

RESUMO

Acyl-CoA synthetase long chain family member 5 (ACSL5), is a member of the acyl-CoA synthetases (ACSs) family that activates long chain fatty acids by catalyzing the synthesis of fatty acyl-CoAs. The dysregulation of ACSL5 has been reported in some cancers, such as glioma and colon cancers. However, little is known about the role of ACSL5 in acute myeloid leukemia (AML). We found that the expression of ACSL5 was higher in bone marrow cells from AML patients compared with that from healthy donors. ACSL5 level could serve as an independent prognostic predictor of the overall survival of AML patients. In AML cells, the ACSL5 knockdown inhibited cell growth both in vitro and in vivo. Mechanistically, the knockdown of ACSL5 suppressed the activation of the Wnt/ß-catenin pathway by suppressing the palmitoylation modification of Wnt3a. Additionally, triacsin c, a pan-ACS family inhibitor, inhibited cell growth and robustly induced cell apoptosis when combined with ABT-199, the FDA approved BCL-2 inhibitor for AML therapy. Our results indicate that ACSL5 is a potential prognosis marker for AML and a promising pharmacological target for the treatment of molecularly stratified AML.


Assuntos
Leucemia Mieloide Aguda , Humanos , Antineoplásicos/uso terapêutico , Apoptose , beta Catenina/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Coenzima A Ligases/genética , Coenzima A Ligases/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Lipoilação , Prognóstico , Via de Sinalização Wnt
5.
Lancet Haematol ; 9(6): e415-e424, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35512726

RESUMO

BACKGROUND: Adults with acute myeloid leukaemia have unsatisfactory clinical outcomes and rates of complete remission. Venetoclax combined with azacytidine or low-dose cytarabine has shown efficacy in adults aged 75 years or older (or 18-74 years with comorbidities precluding intensive chemotherapy) with acute myeloid leukaemia. We aimed to investigate the activity and safety of venetoclax plus 3+7 daunorubicin and cytarabine chemotherapy in adults with acute myeloid leukaemia. METHODS: We conducted a two-stage, single-arm, phase 2 trial at three public hospitals in China. We enrolled patients aged 18-60 years with previously untreated de novo acute myeloid leukaemia and an Eastern Cooperative Oncology Group performance status of 0-2. Patients received induction treatment with intravenous daunorubicin (60 mg/m2 on days 1-3), intravenous cytarabine (100 mg/m2 on days 1-7), and oral venetoclax (100 mg on day 4, 200 mg on day 5, and 400 mg on days 6-11; DAV regimen). For induction therapy, the length of the treatment was 28-35 days per cycle and the number of treatment cycles was one or two. The primary endpoint was the composite complete remission rate (complete remission plus complete remission with incomplete blood cell count recovery) after one cycle of induction treatment, assessed in the as-treated population. Secondary endpoints were bone marrow measurable residual disease by flow cytometry, event-free survival, overall survival, and adverse events. This trial is ongoing and is registered with Chinese Clinical Trial Registry, ChiCTR2000041509. FINDINGS: Between Dec 25, 2020, and July 7, 2021, 36 patients were assessed for eligibility and 33 were enrolled. 15 (45%) patients were men and 18 (55%) were women, and all were Asian. The composite complete remission rate after one cycle of DAV regimen was 91% (95% CI 76-98; 30 of 33 patients) in the entire cohort. 29 (97%) of 30 patients who reached complete remission had undetectable measurable residual disease (ie, <0·1%). Grade 3 or worse adverse events included neutropenia in 33 (100%) of 33 patients, thrombocytopenia in 33 (100%), anaemia in 33 (100%), febrile neutropenia in 18 (55%), pneumonia in seven (21%), and sepsis in four (12%). No treatment-related deaths occurred. With a median follow-up of 11 months (IQR 9-12), estimated 1-year overall survival was 97% (95% CI 91-100) and 1-year event-free survival was 72% (56-94). INTERPRETATION: The DAV regimen represents an effective induction therapy for newly diagnosed adults with acute myeloid leukaemia, which resulted in a high rate of complete remission. These findings are an important contribution to the field, showing a safe strategy to incorporate venetoclax into the most common induction regimen used to treat newly diagnosed acute myeloid leukaemia internationally. FUNDING: Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang, National Natural Science Foundation of China, Key Research and Development Program of Zhejiang. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Citarabina , Leucemia Mieloide Aguda , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Compostos Bicíclicos Heterocíclicos com Pontes/efeitos adversos , Citarabina/uso terapêutico , Daunorrubicina/uso terapêutico , Feminino , Humanos , Masculino , Neoplasia Residual , Sulfonamidas
6.
Exp Hematol Oncol ; 11(1): 13, 2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35277197

RESUMO

BACKGROUND: The differential signaling and outcome of patients with p190 or p210 transcripts of BCR-ABL1 have been systematically investigated in chronic myeloid leukemia rather than in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). METHODS: We analyzed the outcomes and ABL1 mutation profiles in 305 consecutive adult patients with Ph+ ALL treated with chemotherapy plus tyrosine kinase inhibitors. We also studied transcriptome features in two newly diagnosed patients with p190 and p210 using single-cell RNA sequencing (scRNA-seq). RESULTS: P190 and p210 were found in 199 (65%) and 106 (35%) patients, respectively. Compared to patients with p190, a higher white blood cell count (p = 0.05), platelet count (p = 0.047), BCR-ABL1 transcript level (p < 0.001), and lower bone marrow blasts (p = 0.003) were found in patients with p210. Patients with p210 had fewer types of ABL1 mutations (4 vs. 16) and a higher prevalence of T315I and E225K/V mutations (91.3% vs. 68.6%; p = 0.031). Patients with p210 had a similar complete remission rate (91.0% vs. 90.1%; p = 0.805) but a lower complete molecular remission rate at 1 month (9.9% vs. 22.0%; p = 0.031) compared with p190. Patients with p210 had lower 3-year overall survival (OS) and disease-free survival (DFS) rates than those with p190 (3-year DFS: 10.4% vs. 9.2%, p = 0.069, 3-year OS: 44.3% vs. 38.2%, p = 0.018, respectively). Multivariate analysis revealed that p210 was independently associated with worse OS [HR 1.692 (95% CI 1.009-2.838), p = 0.046]. Allogeneic hematopoietic stem-cell transplantation (allo-HSCT) was associated with a better prognosis in patients with p210 (p < 0.0001). In addition, scRNA-seq data showed distinct molecular and cellular heterogeneity between bone marrow cells of the two transcripts. CONCLUSIONS: Ph+ ALL patients with p190 and p210 had different clinical characteristics, outcomes, ABL1 mutation profiles, and transcriptome features. Allo-HSCT could improve the outcomes of patients with p210.

8.
Front Med ; 16(3): 416-428, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34792736

RESUMO

Abivertinib, a third-generation tyrosine kinase inhibitor, is originally designed to target epidermal growth factor receptor (EGFR)-activating mutations. Previous studies have shown that abivertinib has promising antitumor activity and a well-tolerated safety profile in patients with non-small-cell lung cancer. However, abivertinib also exhibited high inhibitory activity against Bruton's tyrosine kinase and Janus kinase 3. Given that these kinases play some roles in the progression of megakaryopoiesis, we speculate that abivertinib can affect megakaryocyte (MK) differentiation and platelet biogenesis. We treated cord blood CD34+ hematopoietic stem cells, Meg-01 cells, and C57BL/6 mice with abivertinib and observed megakaryopoiesis to determine the biological effect of abivertinib on MK differentiation and platelet biogenesis. Our in vitro results showed that abivertinib impaired the CFU-MK formation, proliferation of CD34+ HSC-derived MK progenitor cells, and differentiation and functions of MKs and inhibited Meg-01-derived MK differentiation. These results suggested that megakaryopoiesis was inhibited by abivertinib. We also demonstrated in vivo that abivertinib decreased the number of MKs in bone marrow and platelet counts in mice, which suggested that thrombopoiesis was also inhibited. Thus, these preclinical data collectively suggested that abivertinib could inhibit MK differentiation and platelet biogenesis and might be an agent for thrombocythemia.


Assuntos
Acrilamidas , Plaquetas , Megacariócitos , Piperazinas , Pirimidinas , Acrilamidas/farmacologia , Animais , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Diferenciação Celular , Megacariócitos/citologia , Megacariócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Piperazinas/farmacologia , Pirimidinas/farmacologia
9.
EBioMedicine ; 69: 103441, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34166980

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) is a group of heterogeneous hematologic malignancies correlates with poor prognosis. It is important to identify biomarkers for effective treatment of AML. Kinases participate in many regulatory pathways and biological activities in AML. Previous studies demonstrated that MAP4K1, a serine/threonine kinase, was associated with immune regulation and cancer progression. However, its role and mechanism in acute myeloid leukemia (AML) have not been explored. METHODS: RNA-seq profiling was performed for Homoharringtonine (HHT)-resistant and Homoharringtonine (HHT)-sensitive cell lines. Bioinformatic tools were used for differential analysis. Cell culture and transfection, Cell proliferation, apoptosis and Cell cycle assay, Quantitative RT-PCR, and Western blotting analysis were used to explore biological phenotypes in vitro. FINDINGS: We found that MAP4K1 was highly expressed in HHT-induced resistant AML cell lines. In addition, overexpression of MAP4K1 in AML cells induced resistance of AML cells against HHT. Not only that, the findings of this study showed that overexpression of MAP4K1 was an independent risk factor that predicts poor prognosis of AML. Further, In vitro studies showed that MAP4K1 modulated cell cycle through MAPK and DNA damage/repair pathways. Therefore, MAP4K1 is a potential target for developing therapies for AML. INTERPRETATION: This study demonstrates that MAP4K1 not only regulates HHT resistance but also independently predicts AML prognosis. In addition, understanding the regulatory mechanism of MAP4K1 reveals novel treatment strategies for resistant and refractory AML. Fundings: This work was supported by the National Natural Science Foundation of China (NSFC) (Grant No.81800199, 81670124, 82070118) and the Natural Science Foundation of Zhejiang Province (LY20H080008).


Assuntos
Biomarcadores Tumorais/genética , Resistencia a Medicamentos Antineoplásicos , Leucemia Mieloide Aguda/genética , Proteínas Serina-Treonina Quinases/genética , Animais , Antineoplásicos Fitogênicos/toxicidade , Apoptose , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Dano ao DNA , Reparo do DNA , Mepesuccinato de Omacetaxina/toxicidade , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Sistema de Sinalização das MAP Quinases , Camundongos , Proteínas Serina-Treonina Quinases/metabolismo , Células THP-1 , Transcriptoma
10.
Biomark Res ; 9(1): 30, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933163

RESUMO

Venetoclax (VEN) plus azacitidine has become the first-line therapy for elderly patients with acute myeloid leukemia (AML), and has a complete remission (CR) plus CR with incomplete recovery of hemogram rate of ≥70%. However, the 3-year survival rate of these patients is < 40% due to relapse caused by acquired VEN resistance, and this remains the greatest obstacle for the maintenance of long-term remission in VEN-sensitive patients. The underlying mechanism of acquired VEN resistance in AML remains largely unknown. Therefore, in the current study, nine AML patients with acquired VEN resistance were retrospectively analyzed. Our results showed that the known VEN resistance-associated BCL2 mutation was not present in our cohort, indicating that, in contrast to chronic lymphocytic leukemia, this BCL2 mutation is dispensable for acquired VEN resistance in AML. Instead, we found that reconstructed existing mutations, especially dominant mutation conversion (e.g., expanded FLT3-ITD), rather than newly emerged mutations (e.g., TP53 mutation), mainly contributed to VEN resistance in AML. According to our results, the combination of precise mutational monitoring and advanced interventions with targeted therapy or chemotherapy are potential strategies to prevent and even overcome acquired VEN resistance in AML.

11.
J Transl Med ; 19(1): 181, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33926484

RESUMO

BACKGROUND: Fatty acid oxidation (FAO) provides an important source of energy to promote the growth of leukemia cells. Carnitine palmitoyltransferase 1a(CPT1a), a rate-limiting enzyme of the essential step of FAO, can facilitate cancer metabolic adaptation. Previous reports demonstrated that CPT1a acts as a potential molecular target in solid tumors and hematologic disease. However, no systematic study was conducted to explore the prognostic value of CPT1a expression and possible treatment strategies with CPT1a inhibitor on acute myeloid leukemia (AML). METHODS: The expression of CPT1a in 325 cytogenetically normal AML (CN-AML) patients was evaluated using RT-PCR. The combination effects of ST1326 and ABT199 were studied in AML cells and primary patients. MTS was used to measure the cell proliferation rate. Annexin V/propidium iodide staining and flow cytometry analysis was used to measure the apoptosis rate. Western blot was used to measure the expression of Mcl-1. RNAseq and GC-TOFMS were used for genomic and metabolic analysis. RESULTS: In this study, we found AML patients with high CPT1a expression (n = 245) had a relatively short overall survival (P = 0.01) compared to patients in low expression group (n = 80). In parallel, downregulation of CPT1a inhibits proliferation of AML cells. We also conducted genomic and metabolic interactive analysis in AML patients, and found several essential genes and pathways related to aberrant expression of CPT1a. Moreover, we found downregulation of CPT1a sentitized BCL-2 inhibitor ABT199 and CPT1a-selective inhibitor ST1326 combined with ABT199 had a strong synergistic effect to induce apoptosis in AML cells and primary patient blasts for the first time. The underlying synergistic mechanism might be that ST1326 inhibits pGSK3ß and pERK expression, leading to downregulation of Mcl-1. CONCLUSION: Our study indicates that overexpression of CPT1a predicts poor clinical outcome in AML. CPT1a-selective inhibitor ST1326 combined with Bcl-2 inhibitor ABT199 showed strong synergistic inhibitory effects on AML.


Assuntos
Leucemia Mieloide Aguda , Apoptose , Linhagem Celular Tumoral , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Prognóstico , Sulfonamidas
12.
Mol Cytogenet ; 14(1): 10, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33573663

RESUMO

Mixed phenotype acute leukemia (MPAL) is an uncommon type of leukemia. It is one kind of malignant clonal diseases that expresses more than one genealogical specific antigen simultaneously. Most MPAL patients are associated with clonal chromosomal abnormalities and molecular genetic changes, such as t(9;22) (q34;q11) and KMT2A (MLL) rearrangement. These specific abnormalities usually have important guiding significance in MPAL diagnosis, targeted therapy and prognosis judgment. In this paper, we reported a case of MPAL, T/myeloid (M5) with an unfrequent combination of PML-RARα positivity and t(15;17). The treatment was successful with chemotherapy for both AML and ALL with daunorubicin, cytarabine (DA) and vincristine, prednisone (VP). We reported here this suggestive MPAL case of rare disease condition and effective treatment, in order to provide experience for the early diagnosis and treatment of similar patients.

13.
BMC Med ; 19(1): 28, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33517886

RESUMO

BACKGROUND: Although there are many clinical and molecular biomarkers in acute myeloid leukemia (AML), the novel and reliable biomarkers are still required to predict the overall survival at the time of disease diagnosis. METHODS: In order to identify independent predictors, we firstly selected 60 cytogenetically normal AML (CN-AML) patients using the propensity score analysis to balance the confounders and performed circular RNA (circRNA) sequencing. Next, one outcome related to circRNA was selected and validated in the independent cohort of 218 CN-AML patients. We then constructed circRNA-miRNA-mRNA regulated network and performed cellular metabolomic analysis to decipher the underlying biological insights. RESULTS: We identified 308 circRNAs as independent candidate predictors of overall survival. Hsa_circ_0075451 expression was validated as an independent predictor with a weak predictive ability for overall survival. The regulated network of this circular RNA indicated 84 hub genes that appear to be regulated by 10 miRNAs sponged by hsa_circ_0075451. The regulatory axis of hsa_circ_0075451 -| miR-330-5p/miR-326 -| PRDM16 was validated by the dual luciferase report assay, fluorescence in situ hybridization, and ShRNA interference assay. CONCLUSIONS: Our data demonstrates that hsa_circ_0075451 expression may independently contribute to the poor prognosis of AML and present a novel therapeutic target.


Assuntos
Biomarcadores Tumorais/metabolismo , Leucemia Mieloide Aguda/metabolismo , MicroRNAs/metabolismo , RNA Circular/metabolismo , RNA Mensageiro/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente/métodos , Leucemia Mieloide Aguda/genética , Masculino , Prognóstico , RNA/metabolismo , RNA Mensageiro/metabolismo , Análise de Sequência de RNA
14.
Ther Adv Hematol ; 12: 2040620720976984, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33473264

RESUMO

Some subtypes of acute myeloid leukemia (AML) share morphologic, immunophenotypic, and clinical features of acute promyelocytic leukemia (APL), but lack a PML-RARA (promyelocytic leukemia-retinoic acid receptor alpha) fusion gene. Instead, they have the retinoic acid receptor beta (RARB) or retinoic acid receptor gamma (RARG) rearranged. Almost all of these AML subtypes exhibit resistance to all-trans retinoic acid (ATRA); undoubtedly, the prognosis is poor. Here, we present an AML patient resembling APL with a novel cleavage and polyadenylation specific factor 6 (CPSF6)-RARG fusion, showing resistance to ATRA and poor response to chemotherapy with homoharringtonine and cytarabine. Simultaneously, the patient also had extramedullary infiltration.

15.
Thromb Haemost ; 121(2): 192-205, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32961571

RESUMO

Ibrutinib, an irreversible inhibitor of Bruton's tyrosine kinase, has a favorable safety profile in patients with B cell-related malignancies. A primary adverse effect of ibrutinib is thrombocytopenia in the early stages of treatment, but platelet counts increase or recover as treatment continues. Currently, the effects of ibrutinib on megakaryopoiesis remain unclear. In this study, we investigated the mechanism by which ibrutinib induces thrombocytopenia using cord blood CD34+ hematopoietic stem cells (HSCs), a human megakaryoblastic cell line (SET-2), and C57BL/6 mice. We show that treatment with ibrutinib can suppress CD34+ HSC differentiation into megakaryocytes (MKs) and decrease the number of colony-forming unit-MKs (CFU-MKs). The ibrutinib-dependent inhibition of early megakaryopoiesis seems to mainly involve impaired proliferation of progenitor cells without induction of apoptosis. The effects of ibrutinib on late-stage megakaryopoiesis, in contrast to early-stage megakaryopoiesis, include enhanced MK differentiation, ploidy, and proplatelet formation in CD34+ HSC-derived MKs and SET-2 cells. We also demonstrated that MK adhesion and spreading, but not migration, were inhibited by ibrutinib. Furthermore, we revealed that integrin αIIbß3 outside-in signaling in MKs was inhibited by ibrutinib. Consistent with previous clinical observations, in C57BL/6 mice treated with ibrutinib, platelet counts decreased by days 2 to 7 and recovered to normal levels by day 15. Together, these results reveal the pathogenesis of ibrutinib-induced transient thrombocytopenia. In conclusion, ibrutinib suppresses early megakaryopoiesis, as evidenced by inhibition of MK progenitor cell proliferation and CFU-MK formation. Ibrutinib enhances MK differentiation, ploidy, and proplatelet formation, while it impairs integrin αIIbß3 outside-in signaling.


Assuntos
Adenina/análogos & derivados , Plaquetas/efeitos dos fármacos , Megacariócitos/efeitos dos fármacos , Piperidinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Trombopoese/efeitos dos fármacos , Adenina/farmacologia , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Animais , Plaquetas/citologia , Linhagem Celular , Humanos , Megacariócitos/citologia , Camundongos Endogâmicos C57BL
16.
Int J Biol Sci ; 16(15): 2853-2867, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061801

RESUMO

MicroRNAs (miRNAs) and N6-methyladenosine (m6A) are known to serve as key regulators of acute myeloid leukemia (AML). Our previous microarray analysis indicated miR-550-1 was significantly downregulated in AML. The specific biological roles of miR-550-1 and its indirect interactions and regulation of m6A in AML, however, remain poorly understood. At the present study, we found that miR-550-1 was significantly down-regulated in primary AML samples from human patients, likely owing to hypermethylation of the associated CpG islands. When miR-550-1 expression was induced, it impaired AML cell proliferation both in vitro and in vivo, thus suppressing tumor development. When ectopically expressed, miR-550-1 drove the G0/1 cell cycle phase arrest, differentiation, and apoptotic death of affected cells. We confirmed mechanistically that WW-domain containing transcription regulator-1 (WWTR1) gene was a downstream target of miR-550-1. Moreover, we also identified Wilms tumor 1-associated protein (WTAP), a vital component of the m6A methyltransferase complex, as a target of miR-550-1. These data indicated that miR-550-1 might mediate a decrease in m6A levels via targeting WTAP, which led to a further reduction in WWTR1 stability. Using gain- and loss-of-function approaches, we were able to determine that miR-550-1 disrupted the proliferation and tumorigenesis of AML cells at least in part via the direct targeting of WWTR1. Taken together, our results provide direct evidence that miR-550-1 acts as a tumor suppressor in the context of AML pathogenesis, suggesting that efforts to bolster miR-550-1 expression in AML patients may thus be a viable clinical strategy to improve patient outcomes.


Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Linhagem Celular Tumoral , Proliferação de Células/genética , Genes Supressores de Tumor , Via de Sinalização Hippo , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , MicroRNAs/metabolismo
17.
J Hematol Oncol ; 13(1): 128, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32977829

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) is a fatal hematopoietic malignancy and has a prognosis that varies with its genetic complexity. However, there has been no appropriate integrative analysis on the hierarchy of different AML subtypes. METHODS: Using Microwell-seq, a high-throughput single-cell mRNA sequencing platform, we analyzed the cellular hierarchy of bone marrow samples from 40 patients and 3 healthy donors. We also used single-cell single-molecule real-time (SMRT) sequencing to investigate the clonal heterogeneity of AML cells. RESULTS: From the integrative analysis of 191727 AML cells, we established a single-cell AML landscape and identified an AML progenitor cell cluster with novel AML markers. Patients with ribosomal protein high progenitor cells had a low remission rate. We deduced two types of AML with diverse clinical outcomes. We traced mitochondrial mutations in the AML landscape by combining Microwell-seq with SMRT sequencing. We propose the existence of a phenotypic "cancer attractor" that might help to define a common phenotype for AML progenitor cells. Finally, we explored the potential drug targets by making comparisons between the AML landscape and the Human Cell Landscape. CONCLUSIONS: We identified a key AML progenitor cell cluster. A high ribosomal protein gene level indicates the poor prognosis. We deduced two types of AML and explored the potential drug targets. Our results suggest the existence of a cancer attractor.


Assuntos
Exame de Medula Óssea/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Leucemia Mieloide Aguda/patologia , Análise de Célula Única/métodos , Linhagem da Célula , Células Clonais , Sistemas Computacionais , DNA Mitocondrial/genética , DNA de Neoplasias/genética , Regulação Leucêmica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Leucemia Monocítica Aguda/genética , Leucemia Monocítica Aguda/patologia , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/química , Células-Tronco Neoplásicas/patologia , Fenótipo , Prognóstico , RNA Mensageiro/análise , RNA Neoplásico/análise , Recidiva , Proteínas Ribossômicas/genética , Fatores de Transcrição/fisiologia
20.
Am J Cancer Res ; 10(12): 4527-4537, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33415016

RESUMO

FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) is one of the most common somatic mutations in acute myeloid leukemia (AML). However, the molecular structure characteristics and widely accepted prognostic factors for FLT3-ITD are still not well described. This study aimed to retrospectively examine 81 patients with FLT3-ITD-positive AML diagnosed and treated at the First Affiliated Hospital of Zhejiang University from December 2013 to March 2018 using the next-generation sequencing 185-gene platform. High variant allele frequency (VAF) [> 0.48, P = 0.0089 for overall survival (OS), P = 0.13 for relapse-free survival (RFS)], multiple ITDs (> 1 ITDs, P = 0.011 for OS, P = 0.033 for RFS) and longer insertion length (> 69 bp, P = 0.14 for OS, P = 0.0078 for RFS) predicted poor survival. The study further proposed an easily applicable scoring model for OS using the Least Absolute Shrinkage and Selector Operation (LASSO) Cox regression model. Also, an independent cohort of 30 patients was used for external model validation. The mode was expressed as follows: 0.659 × FLT3-ITD VAF + 0.375 × FLT3-ITD number + 0.807 × Age + 0.688 × DNMT3A + 1.939 × U2AF1 (FLT3-ITD VAF > 0.48 scored 1; FLT3-ITD number scored 1 if carried 1 ITD, 2 if carried ≥ 2 ITDs; age > 44 years scored 1, the presence of DNMT3A or U2AF1 scored 1; 0 for other conditions). It categorized patients into low-risk (L-R, score < 1, n = 20) and high-risk (H-R, score ≥ 1, n = 61) groups based on the risk score with a significant difference in survival (3-year OS, P < 0.0001; 3-year RFS, P = 0.0005). A prognostic nomogram that integrated these five factors was developed with a concordance index calculation [OS: 0.68, 95% CI (0.64-0.72)].

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