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  • 1
    In: Blood, American Society of Hematology, Vol. 108, No. 11 ( 2006-11-16), p. 4812-4812
    Abstract: Imatinib Mesylate (Gleevec™ or Glivec™ from NOVARTIS) is widely used for the treatment of CML inhibiting the BCR-ABL tyrosine kinase activity. Although, 90% of the patients respond to this treatment, resistance to this drug has been seen, mainly due mutations in the tyrosine kinase domain of BCR-ABL. Recently, has been reported that imatinib is a substrate for the ABC-transporters BCRP (breast cancer resistance protein) and MDR1 (P-Glycoprotein). Based in that report, we examined the expression of those two ABC-transporter, by quantitative PCR (Q-PCR) technology, in 29 CML patients who were resistant to IM (9 CP, 17 AP, and 3 BC), in 34 untreated CML patients (23 CP, 10 AP, and 1 BC) and 6 normal blood donors. cDNA was synthesized for RQ-PCR, which was performed on peripheral blood samples drawn after loss of CHR or MCyR for those with resistance to imatinib and prior to start of treatment with imatinib and those untreated patients. All samples were analyzed using SYBER Green technology and reported as the 2−Δ Δ Ct where it assumes that the amplification efficiency of the target gene (BCRP or MDR1) and the internal control gene (ABL) are the same. Resistant patients had a significantly higher levels of BCRP expression than untreated patients, and normal blood donors with a median ratio of 2.1 (range, 0.04–34.2) vs. 0.64 (range, 0–18.6) vs. 0.6 (range, 0.07–1.41) (Wilcoxon test, P 〈 0.0002). For the MDR1 gene expression, patients with resistance to imatinib had also a significantly higher level, median ratio of 1.65 (range, 0.09–10.8) vs. 0.68 (range, 0.01–2.63) in untreated patients and normal blood donors median ratio 0.76 (range, 0.02–1.92) (P 〈 0.0017). Nineteen of 29 resistant patients (65.5%) overexpressed BCRP and 41.3% (12/29) overexpressed MDR1, meantime only 26.5% (9/34) and 11.8% (4/34) of the untreated CML patients overexpressed BCRP and MDR1 respectively (X2 test P=0.004 and P=0,022). Overexpression of BCRP was more frequent in AP of the resistant group (70%) than the untreated patients (30%) (Fisher exact test P=0.05). When comparing the expression of MDR1 between the resitant group in AP (35,3%) and the untreated one in the same phase (40%) no statistic difference was seen (P=1). Patients in CP and BC do not show any difference in the expression of BCRP and MDR1 regardless the presence or not of resistance to imatinib. These data confirms that high expression of BCRP or MDR1 may contribute to imatinib resistance phenotype leading to a reduction in intracellular imatinib concentrations.Further follow-up is necessary for those untreated CML patients that overexpress, at diagnosis, those ABC-transporters BCRP and MDR1. These may reveal correlations between the expression and clinical prognosis and may allow the development of new starategies to overcome imatinib mesylate resistance.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2006
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  • 2
    In: Journal of Clinical Oncology, American Society of Clinical Oncology (ASCO), Vol. 32, No. 15_suppl ( 2014-05-20), p. 7025-7025
    Type of Medium: Online Resource
    ISSN: 0732-183X , 1527-7755
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    Language: English
    Publisher: American Society of Clinical Oncology (ASCO)
    Publication Date: 2014
    detail.hit.zdb_id: 2005181-5
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  • 3
    In: Breast Cancer Research, Springer Science and Business Media LLC, Vol. 7, No. 1 ( 2004-2)
    Type of Medium: Online Resource
    ISSN: 1465-542X
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2004
    detail.hit.zdb_id: 2041618-0
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  • 4
    In: Acta Haematologica, S. Karger AG, Vol. 127, No. 3 ( 2012), p. 165-169
    Abstract: This paper chronicles a 2-year-old girl who presented with acute leukemia/lymphoma syndrome of the T cell immunophenotype. At this time, the cytogenetic analysis of her bone marrow cells showed a reciprocal translocation between the short arm of chromosome 12 and the long arm of chromosome 13, t(12;13)(p13;q14). The immunophenotyping of bone marrow blast cells by flow cytometry revealed a population of cells positive for CD56, CD117, CD45, partial CD33, partial HLA-DR, CD13, CD7, CD2 and CD5. Therefore, a diagnosis of acute leukemia with a mixed T cell/myeloid phenotype was made. The patient had a poor response to classic T cell acute lymphocytic leukemia/lymphoma therapy; thus, her treatment was changed to a myeloid leukemia protocol, which produced a good response. She underwent a successful cord blood transplantation from an unrelated HLA partially matched donor. The coexistence of these two phenotypes prompts questions about the existence of clonal instability, which might influence the choice of therapy. The rarity of the t(12;13)(p13;q14) and the coexistence of T cell/myeloid markers suggest a nonrandom association. To the best of our knowledge, this is the first reported case in which a cell clone bearing a t(12;13)(p13;q14) translocation in a mixed T cell/myeloid lesion was detected.
    Type of Medium: Online Resource
    ISSN: 0001-5792 , 1421-9662
    Language: English
    Publisher: S. Karger AG
    Publication Date: 2012
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  • 5
    In: Acta Haematologica, S. Karger AG, Vol. 127, No. 4 ( 2012), p. 228-234
    Abstract: In this retrospective study we evaluated the pretherapeutic mRNA expression of the 〈 i 〉 hOCT1 〈 /i 〉 (human organic cation transporter 1) gene in patients with chronic-phase (CP) chronic myeloid leukemia (CML) who varied in terms of their response to imatinib (IM). 〈 i 〉 hOCT1 〈 /i 〉 mRNA was quanti & #xFB01;ed by real-time PCR. Patients were classified as expressing either high (n = 44) or low 〈 i 〉 hOCT1 〈 /i 〉 mRNA (n = 44). The complete cytogenetic response rates observed at 6, 12 and 18 months were 47.7, 84.1 and 91%, respectively, in patients with high 〈 i 〉 hOCT1 〈 /i 〉 mRNA and 47.5, 81.8 and 86.3%, respectively, in patients with low 〈 i 〉 hOCT1 〈 /i 〉 transcripts. The major molecular response rates were not significantly different between patients with high and low 〈 i 〉 hOCT1 〈 /i 〉 mRNA after 6 months of therapy (22.7 vs. 9.1%; p = 0.07), but they were significantly different after 12 months (54.5 vs. 31.8%; p = 0.026) and 18 months (77.2 vs. 56.8%; p = 0.034). Complete molecular responses were observed in 5 patients with low and 17 patients with high 〈 i 〉 hOCT1 〈 /i 〉 mRNA (p = 0.003). The 5-year event-free and overall survival analyses revealed no significant differences between the groups. These data imply that knowledge of the pretherapeutic level of 〈 i 〉 hOCT1 〈 /i 〉 could be a useful marker to predict IM therapy outcome in treatment-naïve CP CML patients.
    Type of Medium: Online Resource
    ISSN: 0001-5792 , 1421-9662
    Language: English
    Publisher: S. Karger AG
    Publication Date: 2012
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  • 6
    Online Resource
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    Xia & He Publishing ; 2024
    In:  Oncology Advances Vol. 000, No. 000 ( 2024-3-18), p. 000-000
    In: Oncology Advances, Xia & He Publishing, Vol. 000, No. 000 ( 2024-3-18), p. 000-000
    Type of Medium: Online Resource
    ISSN: 2996-3427
    Language: English
    Publisher: Xia & He Publishing
    Publication Date: 2024
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  • 7
    In: The Lancet Haematology, Elsevier BV, Vol. 3, No. 12 ( 2016-12), p. e581-e591
    Type of Medium: Online Resource
    ISSN: 2352-3026
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2016
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  • 8
    In: Blood, American Society of Hematology, Vol. 134, No. Supplement_1 ( 2019-11-13), p. 4257-4257
    Abstract: Background : The recent efforts to uncover the molecular heterogeneity of myelodysplastic syndromes (MDS), mainly by new sequencing technologies, allow the comprehensive identification of driver mutations and/or altered gene expression recurrently found in a recognizable fraction of patients. Ongoing efforts are being made to clarify the impact of molecular changes on clinical phenotype and prognosis, as well as their role in the pathogenesis of MDS. Refining risk stratification allows the proposition of risk-adapted therapy and may shed light in biology of MDS. Aims: Based on the gene expression of selected metabolic targets, we aimed to design a score system that improves MDS overall survival prediction. Patients and methods: Clinical, mutations and transcriptomic data from CD34+ cells from 159 MDS patients and 17 healthy volunteers freely available at Gene Expression Omnibus (GEO/NCBI: GSE58831) were used in the present work. Forty-one genes related to metabolic processes, previously demonstrated as deregulated among diverse neoplastic conditions, were ranked and asked for differential expression and prognostic impact. Each gene was dichotomized according to Receiving-Operating Curve (ROC) and Cox Proportional-Hazard Model was used for multivariate analysis using gender, age and IPSS-R as cofounders. Genes independently associated with overall survival (OS) were selected to compose the Molecular-Based Score (MBS) and integer weight of each one was defined according Hazard Ratio (HR). Survival curves were constructed using Kaplan-Meyer method and compared with Log-Rank Test. ROC c-statistic was used to measure the predictive function of MBS. Prediction accuracy of MBS was cross-validated by a nonparametric bootstrap procedure with 1,000 resamplings of the original cohort allowing replacement and also estimated their respective 95% confidence interval (95% CI) computing the bias-corrected and accelerated bootstrap interval. Results: Among selected genes, 18 were differentially expressed between CD34+ cells from MDS and healthy volunteers. Fifteen genes predict OS in univariate analysis, of which ACLY (HR: 0.48; 95%CI: 0.24 - 0.96; P=0.04), ANPEP (HR: 2.16; 95%CI: 1.08 - 4.31; P=0.02), PANK1 (HR: 0.43; 95%CI: 0.19 - 0.98; P=0.04), PKM (HR: 2.01; 95%CI: 1.02 - 3.93; P=0.04) and SLC25A5 (HR: 0.52; 95%CI: 0.27 - 0.99; P=0.05) were independently associated with OS. Higher expression of ANPEP and PKM, as well as lower expression of ACLY, PANK1 and SLC25A5 were considered to integer high risk being attributed weight 2 for each condition. MBS varied from 0 to 10 (median=2) and was calculated as: MBS Low-Risk =0 (MBS-LR; n=28); MBS Intermediate-Risk=2 and 4 (MBS-IR; n=90) and High-Risk: ≥6 (MBS-HR; n=48). The modeled MBS showed a ROC c-statistic of 0.699 (95%CI: 0.603 - 0.794) and HR=3.05 (95%CI: 1.81 - 5.05; P 〈 0.001) and efficiently identified patients with different risk: MBS-LR (3-year OS: 100%; median time [MT]: not reached); MBS-IR (3-year OS: 66% [95%CI: 53% - 83%] ; MT: 52.2 months [95%CI: 34.2 - 71.5]) and MBS-HR (3-year OS: 32% [95%CI: 17% - 61%] ; MT: 23.5 months [95%CI: 11.6 - 35.4]). Using Cox Proportional Hazard Model for multivariate analysis, the proposed MBS (HR:2.5 [95%CI: 1.2-4.96] ; P=0.008) was independently associated with OS using gender (HR:0.48 [95%CI: 0.21-1.06]; P=0.07), age (HR:1.03 [95%CI: 1.001-1.07] ; P=0.02) and IPSS-R (HR:0.98 [95%CI: 0.69-1.36]; P=0.88) as confounders. The bootstrap resampling procedure validated the MBS and demonstrated the stability of its prediction (3-year OS for MBS-LR: 100% [95%CI: 100-100%] ; MBS-IR: 66% [95%CI: 49-80%]; MBS-HR: 32% [95%CI: 13-54%] ; P 〈 0.001). Conclusions: The proposed Molecular-Based Score (MBS) independently predict OS with superior efficacy in comparison to the most clinically relevant prognostic factors, and reinforce the therapeutic opportunity of metabolic processes in MDS. Figure Disclosures No relevant conflicts of interest to declare.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2019
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  • 9
    In: Blood, American Society of Hematology, Vol. 118, No. 21 ( 2011-11-18), p. 1701-1701
    Abstract: Abstract 1701 Mutations within the BCR-ABL domain are the most frequent mechanism of imatinib (IM) resistance. The second generation inhibitors (SGI) are indicated for imatinib intolerance or resistance and the initials trials showed similar response rates in IM resistant patients after IM failure, independent of mutation status, with exception of T315I. The aim of this work was to report the frequency of BCR-ABL mutations in chronic myeloid leukemia (CML) patients of a Latin American population and to evaluate the clinical impact of the presence and type of mutations in overall survival (OS), progression free survival (PFS) and in the response to second generation inhibitors (SGI). Methods: retrospective analysis of 17 centers from Latin America. A total of 529 CML patients with mutation analysis performed in samples collected between 2002 and 2011 were included. Mutations were detected by direct sequencing from bone marrow or peripheral blood samples, collected from CML patients. After imatinib resistance, patients were treated with SGI (69%) or other treatments. Overall survival (OS) was calculated from date of mutation detection until last follow-up or death, and progression-free survival (PFS) from date of mutation detection until progression to accelerated phase or blast crisis, last follow-up or death. Survival curves were calculated using the log-rang test (SPSS 14.0 software).Results: the median age of patients at diagnosis was 45 years (5–87). 81% were in chronic phase (CP), 13% in accelerated phase (AP), 6% in blast crisis (BC). According to Sokal score, patients were stratified in low (36%), intermediate (30%) and high risk (34%); 36% had previously used Interferon. The median time from diagnosis until Imatinib treatment was 8 months (0–310) and from Imatinib start until mutation detection was 31 months (1–104). Mutations were found in 188 patients, in the following sites: P-loop (75/40%), nucleotide contact site (34/18%), catalytic domain (44/23%), A-loop (11/6%) and others (24/13%). The most frequent mutations detected were: T315I (30/16%), F359V/C/I (27/14%), M244V (18/9.6%), E255K/V (17/9%), G250E (17/9%), Y253H/F/Y (15/8%), M351T/L (12/6%); Ten patients presented concomitant mutations. On dasatinib treatment 29 mutations (27% T315I) were detected whereas 18 during nilotinib (16.5% T315I). Overall survival in the total group was 61% (95%CI: 51–71%) with a median time of 12 months. There was a significant difference in OS and PFS between non-mutated and mutated patients (76% vs 44% and 64% vs 44% respectively (P= 0.008 and P= 0.001). There was no difference in survival comparing P-loop mutations and others, excluding T315I. Patients with T315I mutations had a poorer outcome in comparison with other mutations (OS 21% vs 62%; PFS 35% vs 55%) (P= 0.04 and 0.06, respectively). In the group with BCR-AL mutations, OS was superior in patients that received a SGI in comparison with other treatments after resistance (50% vs 36% P= 0.007). One hundred patients (19%) died due to: disease progression (72), infections (8), graft versus host disease (2), central nervous system bleeding (2), cardiac failure (1), second neoplasia (1). 14 causes were not reported. Conclusions: Patients with BCR-ABL mutations had an inferior OS and PFS. T315I mutations were associated to a poor outcome. Treatment with SGI prolonged survival of patients after imatinib failure. Disclosures: Pagnano: Novartis: Speakers Bureau; Bristol Myers Squibb: Speakers Bureau. Boquimpani:Novartis: Speakers Bureau; Bristol Myers Squibb: Speakers Bureau. Pasquini:Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bristol Myers Squibb: Speakers Bureau. Spector:Novartis: Membership on an entity's Board of Directors or advisory committees.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2011
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  • 10
    In: Blood, American Society of Hematology, Vol. 134, No. Supplement_1 ( 2019-11-13), p. 5844-5844
    Abstract: Quantitative RT-PCR (RQ-PCR) is an essential test for BCR-ABL transcripts monitoring in patients with chronic myeloid leukemia (CML) treated with tyrosine kinase inhibitors (TKI), to guide therapy and for monitoring after a discontinuation attempt in patients with deep molecular response. RT-PCR (RQ-PCR) is currently not reimbursed by the public health system in Brazil. Aims: To assess the proportion of CML patients treated with first-line imatinib eligible for discontinuation, and to calculate the financial impact resulting from IM discontinuation. Methods: Between January 2010 and December 2011, 151 consecutive cases of chronic phase myeloid leukemia treated with Glivec first-line therapy were evaluated. Between June and December 2013 there was a switch in treatment from Glivec to generic IM. Cases that exhibited stable MR4.5 for 2 years with first-line IM were selected for the study. Cases which switched treatment to second-generation inhibitors and patients older than 75 years of age were excluded from the study. The methodology used was a pharmacoeconomic cost-utility analysis. Glivec monthly cost has been estimated at U$ 3,257.54 and the generic IM U$ 365.48, while the unitary value for the PCR test was U$ 117.49. In order to calculate the period of IM consumption, the median age of the patients and the life expectancy data released in 2015 by the Brazilian Institute of Geography and Statistics (IBGE) of 75 years was considered. In the first analysis, the life expectancy for the sample group, and the total cost of treatment (cost of Glivec, generic IM and four annual RQ-PCR tests for each patient) were calculated. The second analysis consisted of a hypothetical calculation of costs under the scenario where the study group is therapy-free (estimating that the survival rate under discontinued therapy was similar to data available in the literature, with discontinuation success of 50% in this group) with molecular monitoring by PCR monthly in the first year, bimestrial in the second year and every three months from the third year on. Results: One hundred fifty-one cases were analyzed, with a median age at diagnosis of 45. From those, 56 (37%) patients achieved stable MR4.5 with a median time to achieve MR4.5 of 71 months. The median duration of follow-up was 8 (0-10) years. In the last follow-up, 108 patients were still in treatment, 10% (11/108) with Glivec, 90% (97/108) on generic IM. Patients excluded from the analysis: 4 cases aged more than 75 years; 13 that switched therapy to another TKI and one during the bone marrow transplant period. Finally, 38/56 (25%) patients who obtained MR4.5 with IM were eligible for analysis. Analysis 1: Total treatment cost for the 38 eligible cases, if the individuals sustained continuous use of IM, considering the life expectancy of 75 years. The calculations resulted in an average of 29 years of treatment, with an estimated cost of U$ 9,363,866.00. Analysis 2: The cost after discontinuation of generic IM, estimating that 50% of patients would resume the treatment. Nineteen cases were analyzed. The costs related to the monthly PCR exam in year 1, bimestrial exam in year 2 and trimester in year 3, until the patient reaches 75 years of age, have been calculated, with a total cost of U$ 7,823.515. Conclusions: The economy resulting from the discontinuation of treatment (US$1.540.340,00) by 19 patients could support 219 patients tests over 29 years, or 12.110 tests each year. This data is relevant, providing that RQ-PCR is essential for the appropriate management of CML and to allow safe discontinuation of the therapy in eligible patients. Such results may help to change the current health policies concerning RQ-PCR tests reimbursement for CML management and future attempting of TFR in Brazil. Disclosures Centrone: Novartis: Honoraria; Janssen: Honoraria. Magalhaes:Novartis: Honoraria. Pagnano:Pint Pharma: Consultancy; Abbvie: Consultancy; Sandoz: Consultancy.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2019
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
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