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1.
Waste Manag ; 178: 321-330, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38430746

RESUMO

Recycling of post-consumer waste wood material is becoming an increasingly appealing alternative to disposal. However, its huge heterogeneity is calling for an assessment of the material characteristics in order to define the best recycling option and intended reuse. In fact, waste wood comes into a variety of uses/types of wood, along with several levels of contamination, and it can be divided into different categories based on its composition and quality grade. This study provides the measurement of more than a hundred waste wood samples and their characterisation using a hand-held NIR spectrophotometer. Three classification methods, i.e. K-nearest Neighbours (KNN), Principal Component Analysis - Linear Discriminant Analysis (PCA-LDA) and PCA-KNN, have been compared to develop models for the sorting of waste wood in quality categories according to the best-suited reuse. In addition, the classification performance has been investigated as a function of the number of the spectral measurements of the sample and as the average of the spectral measurements. The results showed that PCA-KNN performs better than the other classification methods, especially when the material is ground to 5 cm of particle size and the spectral measurements are averaged across replicates (classification accuracy: 90.9 %). NIR spectroscopy, coupled with chemometrics, turned out to be a promising tool for the real-time sorting of waste wood material, ensuring a more accurate and sustainable waste wood management. Obtaining real-time information about the quality and characteristics of waste wood material translates into a decision of the best recycling option, increasing its recycling potential.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Gerenciamento de Resíduos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Madeira , Reciclagem , Análise Discriminante , Resíduos
2.
Foods ; 12(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37685185

RESUMO

Strawberry is the most cultivated berry fruit globally and it is really appreciated by consumers because of its characteristics, mainly bioactive compounds with antioxidant properties. During the breeding process, it is important to assess the quality characteristics of the fruits for a better selection of the material, but the conventional approaches involve long and destructive lab techniques. Near infrared spectroscopy (NIR) could be considered a valid alternative for speeding up the breeding process and is not destructive. In this study, a total of 216 strawberry fruits belonging to four different cultivars have been collected and analyzed with conventional lab analysis and NIR spectroscopy. In detail, soluble solid content, acidity, vitamin C, anthocyanin, and phenolic acid have been determined. Partial least squares discriminant analysis (PLS-DA) models have been developed to classify strawberry fruits belonging to the four genotypes according to their quality and nutritional properties. NIR spectroscopy could be considered a valid non-destructive phenotyping method for monitoring the nutritional parameters of the fruit and ensuring the fruit quality, speeding up the breeding program.

3.
Cells ; 12(13)2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37443737

RESUMO

The introduction of tyrosine kinase inhibitors (TKIs) has changed the treatment paradigm of chronic myeloid leukemia (CML), leading to a dramatic improvement of the outcome of CML patients, who now have a nearly normal life expectancy and, in some selected cases, the possibility of aiming for the more ambitious goal of treatment-free remission (TFR). However, the minority of patients who fail treatment and progress from chronic phase (CP) to accelerated phase (AP) and blast phase (BP) still have a relatively poor prognosis. The identification of predictive elements enabling a prompt recognition of patients at higher risk of progression still remains among the priorities in the field of CML management. Currently, the baseline risk is assessed using simple clinical and hematologic parameters, other than evaluating the presence of additional chromosomal abnormalities (ACAs), especially those at "high-risk". Beyond the onset, a re-evaluation of the risk status is mandatory, monitoring the response to TKI treatment. Moreover, novel critical insights are emerging into the role of genomic factors, present at diagnosis or evolving on therapy. This review presents the current knowledge regarding prognostic factors in CML and their potential role for an improved risk classification and a subsequent enhancement of therapeutic decisions and disease management.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Aberrações Cromossômicas , Crise Blástica , Medição de Risco
4.
Anal Chim Acta ; 1275: 341564, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37524459

RESUMO

In Europe, the volume of waste wood is increasing. Waste wood can be reused, promoting circular economy and avoiding landfills. It can be used as a bioenergy feedstock reducing the use of fossil fuels, or be reused for producing new composite wood material. Only wood with hazardous substances needs to be disposed. To this aim waste wood samples were collected from a panel board company and several recycling centres in Italy and Denmark. The samples were assigned to waste wood categories and analysed by Near Infrared Spectroscopy. Principal Component Analysis was used to investigate sample variability and Soft Independent Modelling of Class Analogies (SIMCA) for classifying the samples according to the appropriate reuse: energy production, panel board production or landfill. The results are good, with a classification rate of 90% for virgin wood material and 86.7% for treated wood material. The classification of waste wood is key for turning it into a secondary resource.

5.
Biomark Res ; 11(1): 29, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36894973

RESUMO

BACKGROUND: The SETD2 tumor suppressor gene encodes a histone methyltransferase that safeguards transcription fidelity and genomic integrity via trimethylation of histone H3 lysine 36 (H3K36Me3). SETD2 loss of function has been observed in solid and hematologic malignancies. We have recently reported that most patients with advanced systemic mastocytosis (AdvSM) and some with indolent or smoldering SM display H3K36Me3 deficiency as a result of a reversible loss of SETD2 due to reduced protein stability. METHODS: Experiments were conducted in SETD2-proficient (ROSAKIT D816V) and -deficient (HMC-1.2) cell lines and in primary cells from patients with various SM subtypes. A short interfering RNA approach was used to silence SETD2 (in ROSAKIT D816V cells), MDM2 and AURKA (in HMC-1.2 cells). Protein expression and post-translational modifications were assessed by WB and immunoblotting. Protein interactions were tested by using co-immunoprecipitation. Apoptotic cell death was evaluated by flow cytometry after annexin V and propidium iodide staining, respectively. Drug cytotoxicity in in vitro experiments was evaluated by clonogenic assays. RESULTS: Here, we show that the proteasome inhibitors suppress cell growth and induce apoptosis in neoplastic mast cells by promoting SETD2/H3K36Me3 re-expression. Moreover, we found that Aurora kinase A and MDM2 are implicated in SETD2 loss of function in AdvSM. In line with this observation, direct or indirect targeting of Aurora kinase A with alisertib or volasertib induced reduction of clonogenic potential and apoptosis in human mast cell lines and primary neoplastic cells from patients with AdvSM. Efficacy of Aurora A or proteasome inhibitors was comparable to that of the KIT inhibitor avapritinib. Moreover, combination of alisertib (Aurora A inhibitor) or bortezomib (proteasome inhibitor) with avapritinib allowed to use lower doses of each drug to achieve comparable cytotoxic effects. CONCLUSIONS: Our mechanistic insights into SETD2 non-genomic loss of function in AdvSM highlight the potential value of novel therapeutic targets and agents for the treatment of patients who fail or do not tolerate midostaurin or avapritinib.

6.
Front Oncol ; 12: 901132, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992847

RESUMO

In chronic myeloid leukemia (CML), Aurora kinase A and Polo like kinase 1 (PLK1), two serine-threonine kinases involved in the maintenance of genomic stability by preserving a functional G2/M checkpoint, have been implicated in BCR::ABL1-independent resistance to the tyrosine kinase inhibitor (TKI) imatinib mesylate and in leukemic stem cell (LSC) persistence. It can be speculated that the observed deregulated activity of Aurora A and Plk1 enhances DNA damage, promoting the occurrence of additional genomic alterations contributing to TKI resistance and ultimately driving progression from chronic phase to blast crisis (BC). In this study, we propose a new therapeutic strategy based on the combination of Aurora kinase A or PLK1 inhibition with danusertib or volasertib, respectively, and WEE1 inhibition with AZD1775. Danusertib and volasertib used as single drugs induced apoptosis and G2/M-phase arrest, associated with accumulation of phospho-WEE1. Subsequent addition of the WEE1 inhibitor AZD1775 in combination significantly enhanced the induction of apoptotic cell death in TKI-sensitive and -resistant cell lines as compared to both danusertib and volasertib alone and to the simultaneous combination. This schedule indeed induced a significant increase of the DNA double-strand break marker γH2AX, forcing the cells through successive replication cycles ultimately resulting in apoptosis. Finally, combination of danusertib or volasertib+AZD1775 significantly reduced the clonogenic potential of CD34+ CML progenitors from BC patients. Our results may have implications for the development of innovative therapeutic approaches aimed to improve the outcomes of patients with multi-TKI-resistant or BC CML.

7.
Leukemia ; 36(9): 2250-2260, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35908105

RESUMO

One of the indications for BCR::ABL1 mutation testing in chronic myeloid leukemia (CML) is when tyrosine kinase inhibitor therapy (TKI) needs to be changed for unsatisfactory response. In this study, we evaluated a droplet digital PCR (ddPCR)-based multiplex strategy for the detection and quantitation of transcripts harbouring mutations conferring resistance to second-generation TKIs (2GTKIs). Parallel quantitation of e13a2, e14a2 and e1a2 BCR::ABL1 fusion transcripts enables to express results as percentage of mutation positive- over total BCR::ABL1 transcripts. We determined the limit of blank in 60 mutation-negative samples. Accuracy was demonstrated by further analysis of 48 samples already studied by next generation sequencing (NGS). Mutations could be called down to 0.5% and across 3-logs of BCR::ABL1 levels. Retrospective review of BCR::ABL1 NGS results in 513 consecutive CML patients with non-optimal response to first- or second-line TKI therapy suggested that a ddPCR-based approach targeted against 2GTKI-resistant mutations would score samples as mutation-negative in 22% of patients with warning response to imatinib but only in 6% of patients with warning response to 2GTKIs. We conclude ddPCR represents an attractive method for easy, accurate and rapid screening for 2GTKI-resistant mutations impacting on TKI selection, although ddPCR cannot identify compound mutations.


Assuntos
Proteínas de Fusão bcr-abl , Leucemia Mielogênica Crônica BCR-ABL Positiva , Resistencia a Medicamentos Antineoplásicos , Humanos , Mutação , Reação em Cadeia da Polimerase , Inibidores de Proteínas Quinases
8.
Onco Targets Ther ; 15: 103-116, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35115784

RESUMO

Protein kinases (PKs) play crucial roles in cellular proliferation and survival, hence their deregulation is a common event in the pathogenesis of solid and hematologic malignancies. Targeting PKs has been a promising strategy in cancer treatment, and there are now a variety of approved anticancer drugs targeting PKs. However, the phenomenon of resistance remains an obstacle to be addressed and overcoming resistance is a goal to be achieved. Chronic myeloid leukemia (CML) is the first as well as one of the best examples of a cancer that can be targeted by molecular therapy; hence, it can be used as a model disease for other cancers. This review aims to summarize up-to-date knowledge on the main mechanisms implicated in resistance to PK inhibitory therapies and to outline the main strategies that are being explored to overcome resistance. The importance of molecular diagnostics and disease monitoring in counteracting resistance will also be discussed.

9.
Cancers (Basel) ; 14(3)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35159005

RESUMO

Systemic mastocytosis (SM) is due to the pathologic accumulation of neoplastic mast cells in one or more extracutaneous organ(s). Although midostaurin, a multikinase inhibitor active against both wild-type and D816V-mutated KIT, improves organ damage and symptoms, a proportion of patients relapse or have resistant disease. It is well known that Aurora kinase A (AKA) over-expression promotes tumorigenesis, but its role in the pathogenesis of systemic mastocytosis (SM) has not yet been investigated. Evidence from the literature suggests that AKA may confer cancer cell chemo-resistance, inhibit p53, and enhance Polo-like kinase 1 (Plk1), CDK1, and cyclin B1 to promote cell cycle progression. In this study, we aimed to investigate the pathogenetic role of AKA and Plk1 in the advanced forms of SM. We demonstrate here, for the first time, that SM cell lines display hyper-phosphorylated AKA and Plk1. Danusertib (Aurora kinase inhibitor) and volasertib (Plk1 inhibitor) inhibited growth and induced apoptotic cell death in HMC-1.1 and -1.2 cells. Their growth-inhibitory effects were associated with cell cycle arrest and the activation of apoptosis. Cell cycle arrest was associated with increased levels of phospho-Wee1. Wee1 inhibition by MK1775 after 24 h treatment with danusertib or volasertib, when cells were arrested in G2 phase and Wee1, was overexpressed and hyper-activated, resulting in a significantly higher rate of apoptosis than that obtained from concomitant treatment with danusertib or volasertib + MK1775 for 48 h. In conclusion, Plk1 and AKA, alone or together with Wee1, are attractive therapeutic targets in neoplastic MCs. Repurposing Plk1 or AKA ± Wee1 inhibitors in advanced clinical development for other indications is a therapeutic strategy worthy of being explored, in order to improve the outcome of patients with advanced SM.

10.
Front Oncol ; 11: 728613, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660293

RESUMO

FMS-like tyrosine kinase 3 (FLT3) is among the most common driver genes recurrently mutated in acute myeloid leukemia (AML), accounting for approximately 30% of cases. Activating mutations of the FLT3 receptor include internal tandem duplications (ITD) that map to the auto-inhibitory juxtamembrane (JM) domain or point mutations within the tyrosine kinase domain (TKD). Several FLT3 tyrosine kinase inhibitors have been developed in the last few years, but midostaurin is currently the only one approved for the treatment of newly diagnosed patients harboring FLT3 mutations. Here we describe for the first time a novel in-frame deletion in exon 14 (JM domain) of the FLT3 gene, that we identified in a young woman with CBFb-MYH11-positive AML. We demonstrated that this novel FLT3 variant is pathogenic, since it is responsible for constitutive activation of FLT3 receptor. Finally, ex-vivo studies demonstrated that this novel mutation is sensitive to midostaurin.

11.
Int J Mol Sci ; 22(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202238

RESUMO

Acute myeloid leukemia (AML) is a hematologic malignancy caused by a wide range of alterations responsible for a high grade of heterogeneity among patients. Several studies have demonstrated that the hypoxic bone marrow microenvironment (BMM) plays a crucial role in AML pathogenesis and therapy response. This review article summarizes the current literature regarding the effects of the dynamic crosstalk between leukemic stem cells (LSCs) and hypoxic BMM. The interaction between LSCs and hypoxic BMM regulates fundamental cell fate decisions, including survival, self-renewal, and proliferation capacity as a consequence of genetic, transcriptional, and metabolic adaptation of LSCs mediated by hypoxia-inducible factors (HIFs). HIF-1α and some of their targets have been associated with poor prognosis in AML. It has been demonstrated that the hypoxic BMM creates a protective niche that mediates resistance to therapy. Therefore, we also highlight how hypoxia hallmarks might be targeted in the future to hit the leukemic population to improve AML patient outcomes.


Assuntos
Medula Óssea/metabolismo , Medula Óssea/patologia , Hipóxia/metabolismo , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/metabolismo , Microambiente Tumoral , Animais , Linhagem Celular Tumoral , Reprogramação Celular , Gerenciamento Clínico , Suscetibilidade a Doenças , Metabolismo Energético , Epigênese Genética , Regulação Leucêmica da Expressão Gênica , Humanos , Fator 1 Induzível por Hipóxia/metabolismo , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , Terapia de Alvo Molecular , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais
12.
Mediterr J Hematol Infect Dis ; 13(1): e2021046, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34276915

RESUMO

Over the past decade, we have witnessed significant advances in the molecular characterization of systemic mastocytosis (SM). This has provided important information for a better understanding of the pathogenesis of the disease but has also practically impacted the way we diagnose and manage it. Advances in molecular testing have run in parallel with advances in therapeutic targeting of constitutive active KIT, the major driver of the disease. Therefore, assessing the molecular landscape in each SM patient is essential for diagnosis, prognosis, treatment, and therapeutic efficacy monitoring. This is facilitated by the routine availability of novel technologies like digital PCR and NGS. This review aims to summarize the pathogenesis of the disease, discuss the value of molecular diagnostic testing and how it should be performed, and provide an overview of present and future therapeutic concepts based on fine molecular characterization of SM patients.

13.
Int J Mol Sci ; 22(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209376

RESUMO

Chronic myeloid leukemia (CML) is a classical example of stem cell cancer since it arises in a multipotent hematopoietic stem cell upon the acquisition of the t(9;22) chromosomal translocation, that converts it into a leukemic stem cell (LSC). The resulting BCR-ABL1 fusion gene encodes a deregulated tyrosine kinase that is recognized as the disease driver. Therapy with tyrosine kinase inhibitors (TKIs) eliminates progenitor and more differentiated cells but fails to eradicate quiescent LSCs. Thus, although many patients obtain excellent responses and a proportion of them can even attempt treatment discontinuation (treatment free remission [TFR]) after some years of therapy, LSCs persist, and represent a potentially dangerous reservoir feeding relapse and hampering TFR. Over the past two decades, intensive efforts have been devoted to the characterization of CML LSCs and to the dissection of the cell-intrinsic and -extrinsic mechanisms sustaining their persistence, in an attempt to find druggable targets enabling LSC eradication. Here we provide an overview and an update on these mechanisms, focusing in particular on the most recent acquisitions. Moreover, we provide a critical appraisal of the clinical relevance and feasibility of LSC targeting in CML.


Assuntos
Sistemas de Liberação de Medicamentos , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Células-Tronco Neoplásicas/enzimologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética
14.
Front Chem ; 9: 722090, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071179

RESUMO

Waste wood is becoming an appealing alternative material to virgin wood, and the main drivers are the increased demand for waste wood by the panel industry, the introduction of renewable energy policies, and the waste framework directive. In fact, the use of waste wood as a secondary resource is favored over both landfills and combustion. The best reuse and cascading use of the material are linked to its characteristics. That is why it is important to know the chemical composition and the variation in the properties of such a heterogeneous material. In this article, a sampling study was carried out in a panel board company located in the northern part of Italy. In order to investigate the heterogeneity of waste wood, all samples have been analyzed by near-infrared spectroscopy. Nested analysis of variance and principal component analysis have been used to evaluate the heterogeneity and the variation in sample properties. The approach gives information about how to ensure representative measurements and efficiently describe the variability of the material. The results suggest that it is important to have replicates or at least two subsamples for each lot and then measure each of these with at least 100 scans, in order to get representative measurements and describe the variability of the material. The determination of waste wood composition and variability is the focal point for improving the sorting process and increasing the reuse of waste wood, avoiding expensive landfills and risks for human health and the environment.

15.
Int J Mol Sci ; 21(11)2020 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-32498255

RESUMO

In recent years, molecular characterization and management of patients with systemic mastocytosis (SM) have greatly benefited from the application of advanced technologies. Highly sensitive and accurate assays for KIT D816V mutation detection and quantification have allowed the switch to non-invasive peripheral blood testing for patient screening; allele burden has prognostic implications and may be used to monitor therapeutic efficacy. Progress in genetic profiling of KIT, together with the use of next-generation sequencing panels for the characterization of associated gene mutations, have allowed the stratification of patients into three subgroups differing in terms of pathogenesis and prognosis: i) patients with mast cell-restricted KIT D816V; ii) patients with multilineage KIT D816V-involvement; iii) patients with "multi-mutated disease". Thanks to these findings, new prognostic scoring systems combining clinical and molecular data have been developed. Finally, non-genetic SETD2 histone methyltransferase loss of function has recently been identified in advanced SM. Assessment of SETD2 protein levels and activity might provide prognostic information and has opened new research avenues exploring alternative targeted therapeutic strategies. This review discusses how progress in recent years has rapidly complemented previous knowledge improving the molecular characterization of SM, and how this has the potential to impact on patient diagnosis and management.


Assuntos
Alelos , Histona-Lisina N-Metiltransferase/genética , Mastocitose Sistêmica/diagnóstico , Mastocitose Sistêmica/terapia , Mutação , Proteínas Proto-Oncogênicas c-kit/genética , Linhagem da Célula , Citogenética , Variação Genética , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Mastócitos/metabolismo , Fenótipo , Prognóstico
16.
Foods ; 9(4)2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32268548

RESUMO

The determination of strawberry fruit quality through the traditional destructive lab techniques has some limitations related to the amplitude of the samples, the timing and the applicability along all phases of the supply chain. The aim of this study was to determine the main qualitative characteristics through traditional lab destructive techniques and Near Infrared Spectroscopy (NIR) in fruits of five strawberry genotypes. Principal Component Analysis (PCA) was applied to search for spectral differences among all the collected samples. A Partial Least Squares regression (PLS) technique was computed in order to predict the quality parameters of interest. The PLS model for the soluble solids content prediction was the best performing-in fact, it is a robust and reliable model and the validation values suggested possibilities for its use in quality applications. A suitable PLS model is also obtained for the firmness prediction-the validation values tend to worsen slightly but can still be accepted in screening applications. NIR spectroscopy represents an important alternative to destructive techniques, using the infrared region of the electromagnetic spectrum to investigate in a non-destructive way the chemical-physical properties of the samples, finding remarkable applications in the agro-food market.

18.
Parkinsonism Relat Disord ; 55: 134-137, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29887357

RESUMO

BACKGROUND: Parkinson's disease (PD) is the second most common neurodegenerative disorder, and the most common neurodegenerative form of parkinsonism. Recently, a pathogenic mutation (p.N855S) in DNAJC13 was linked to autosomal dominant Lewy body PD in a Dutch-German-Russian Mennonite multi-incident kindred, and was found in five additional patients. In this study, we performed a comprehensive screening of the DNAJC13 gene in familial PD and sporadic PD to assess the frequency of known and novel rare nonsynonymous variants. METHODS: We screened 563 sporadic and 168 familial PD patients and a control series (n = 1000) for the coding region of DNAJC13. RESULTS: Our sequencing analysis identified two carriers of the c.2708G > A (p.R903K) variant in exon 24 of DNAJC13. One of these carriers is a familial PD. CONCLUSION: The p. R903K variant was not found in 1000 healthy controls and it is localized in a functional domain of the DNAJC13 protein. Further studies are necessary to evaluate the role of DNAJC13 variants in PD.


Assuntos
Predisposição Genética para Doença/genética , Proteínas de Choque Térmico HSP40/genética , Mutação/genética , Doença de Parkinson/epidemiologia , Doença de Parkinson/genética , Idoso , Análise Mutacional de DNA , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade
19.
Mol Cancer ; 17(1): 49, 2018 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-29455643

RESUMO

Deregulated activity of BCR-ABL1, a nonreceptor tyrosine kinase encoded by the fusion gene resulting from the t(9;22)(q34;q11) chromosomal translocation, is thought to be the driver event responsible for initiation and maintenance of chronic myeloid leukemia (CML). BCR-ABL1 was one of the first tyrosine kinases to be implicated in a human malignancy and the first to be successfully targeted. Imatinib mesylate, the first tyrosine kinase inhibitor (TKI) to be approved for therapeutic use, was hailed as a magic bullet against cancer and remains one of the safest and most effective anticancer agents ever developed. Second- and third-generation TKIs were later introduced to prevent or counteract the problem of drug resistance, that may arise in a small proportion of patients. They are more potent molecules, but have been associated to more serious side effects and complications. Patients achieving stable optimal responses to TKI therapy are predicted to have the same life expectancy of the general population. However, TKIs do not 'cure' CML. Only a small proportion of cases may attempt therapy discontinuation without experiencing subsequent relapse. The great majority of patients will have to assume TKIs indefinitely - which raises serious pharmacoeconomic concerns and is now shifting the focus from efficacy to compliance and quality of life issues. Here we retrace the steps that have led from the biological acquisitions regarding BCR-ABL1 structure and function to the development of inhibitory strategies and we discuss drug resistance mechanism and how they can be addressed.


Assuntos
Inibidores de Proteínas Quinases/uso terapêutico , Animais , Resistencia a Medicamentos Antineoplásicos , Humanos , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
Oncotarget ; 8(50): 88244-88250, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-29152155

RESUMO

Chibby 1 (CBY1) is a small and evolutionarily conserved protein, which act as ß-catenin antagonist. CBY1 is encoded by C22orf2 (22q13.1) Its antagonistic function on ß-catenin involves the direct interaction with: The C-terminal activation domain of ß-catenin, which hinders ß-catenin binding with Tcf/Lef transcription factors hence repressing ß-catenin transcriptional activation. 14-3-3 scaffolding proteins (σ or ξ), which drive CBY1 nuclear export into a stable tripartite complex with ß-catenin. The relative proximity of C22orf2 gene encoding for CBY1 to the BCR breakpoint on chromosome 22q11, whose translocation and rearrangement with the c-ABL is the causative event of chronic myeloid leukemia (CML), suggested that gene haploinsufficiency may play a role in the disease pathogenesis and progression. We found CBY1 down-modulation associated with the BCR-ABL1, promoted by transcriptional mechanisms (promoter hyper-methylation) and post-transcriptional events, addressing the protein towards proteasome-dependent degradation through SUMOylation. CBY1 reduced expression in clonal progenitors and, more importantly, in leukemic stem cells (LSC), is contingent upon the tyrosine kinase (TK) activity of BCR-ABL1 fusion protein. Accordingly, its induction by Imatinib (IM) and second generation TK inhibitors contributes to ß-catenin inactivation through multiple events encompassing the activation of endoplasmic reticulum (ER) stress-associated unfolded protein response (UPR) and autophagy, eventually leading to apoptotic death. These findings support the advantage of combined regimens including drugs targeting DNA epigenetics and/or proteasome to eradicate the BCR-ABL1+ hematopoiesis.

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