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Supplementary Table S3 from Down-Regulation of hsa-miR-10a in Chronic Myeloid Leukemia CD34+ Cells Increases USF2-Mediated Cell Growth

Supplementary Figures S1-S6 from Down-Regulation of hsa-miR-10a in Chronic Myeloid Leukemia CD34+ Cells Increases USF2-Mediated Cell Growth

Supplementary Methods, Figures 1-3, Tables 1-6 from Epigenetic Silencing of the Tumor Suppressor MicroRNA Hsa-miR-124a Regulates CDK6 Expression and Confers a Poor Prognosis in Acute Lymphoblastic Leukemia

Simple Summary After the recent irruption of asciminib into the therapeutic arsenal for chronic myeloid leukemia, real-life data remain scarce to determine which patients may benefit most from this drug. Data on the efficacy of the drug in real-world setting have been reported, but a detailed analysis of the toxicity profile and the influence of prior intolerance to classical tyrosine kinase inhibitors (TKIs) has not been performed. The aim of the present analysis is to study in detail the toxicity profile of asciminib as well as to describe the risk of cross-toxicity with classical TKIs. These results may help to select the patient profile with the best chance of therapeutic success with asciminib monotherapy. (1) Background: Despite the prognostic improvements achieved with tyrosine kinase inhibitors (TKIs) in chronic myeloid leukemia (CML), a minority of patients still fail TKIs. The recent introduction of asciminib may be a promising option in intolerant patients, as it is a first-in-class inhibitor with a more selective mechanism of action different from the ATP-competitive inhibition that occurs with TKIs. Therefore, our goal was to analyze toxicities shown with asciminib as well as to study cross-toxicity with previous TKIs. (2) Methods: An observational, multicenter, retrospective study was performed with data from 77 patients with CML with therapeutic failure to second-generation TKIs who received asciminib through a managed-access program (MAP) (3) Results: With a median follow-up of 13.7 months, 22 patients (28.5%) discontinued treatment: 32% (7/22) due to intolerance and 45% (10/22) due to resistance. Fifty-five percent of the patients reported adverse effects (AEs) with asciminib and eighteen percent grade 3-4. Most frequent AEs were: fatigue (18%), thrombocytopenia (17%), anemia (12%), and arthralgias (12%). None of the patients experienced cardiovascular events or occlusive arterial disease. Further, 26%, 25%, and 9% of patients required dose adjustment, temporary suspension, or definitive discontinuation of treatment, respectively. Toxicities under asciminib seemed lower than with prior TKIs for anemia, cardiovascular events, pleural/pericardial effusion, diarrhea, and edema. Cross-toxicity risk was statistically significant for thrombocytopenia, anemia, neutropenia, fatigue, vomiting, and pancreatitis. (4) Conclusion: Asciminib is a molecule with a good safety profile and with a low rate of AEs. However, despite its new mechanism of action, asciminib presents a risk of cross-toxicity with classical TKIs for some AEs.

Gemtuzumab ozogamicin (GO) is a conjugate of a monoclonal antibody and calicheamicin, which has been reapproved for the treatment of acute myeloid leukemia (AML). AML patients with the CD33 rs12459419 CC genotype might benefit from the addition of GO to intensive treatment in contrast to patients with CT/TT genotypes. Nevertheless, contradictory results have been reported. We sought to shed light on the prediction of GO response in AML patients with rs12459419 polymorphism who were treated with GO in the consolidation ( n = 70 ) or reinduction ( n = 20 ) phase. The frequency distribution of the rs12459419 polymorphism in the complete cohort of patients was 44.4% ( n = 40 ), 50% ( n = 45 ), and 5.6% ( n = 5 ) for CC, CT, and TT genotypes, respectively. Regarding the patients treated with GO for consolidation, we performed a Kaplan-Meier analysis of overall survival and relapse-free survival according to the rs12459419 polymorphism (CC vs. CT/TT patients) and genetic risk using the European Leukemia Net (ELN) 2010 risk score. We also carried out a Cox regression analysis for the prediction of overall survival, with age and ELN 2010 as covariates. We found no statistical significance in the univariate or multivariate analysis. Additionally, we performed a global Kaplan-Meier analysis for the patients treated with GO for reinduction and did not find significant differences; however, our cohort was too small to draw any conclusion from this analysis. The use of GO in consolidation treatment is included in the approval of the compound; however, evidence regarding its efficacy in this setting is lacking. Rs12459419 polymorphism could help in the selection of patients who might benefit from GO. Regrettably, in our cohort, the rs12459419 polymorphism does not seem to be an adequate tool for the selection of patients who might benefit from the addition of GO in consolidation cycles.

Gemtuzumab ozogamicin (GO) is a conjugate of a monoclonal antibody and calicheamicin, which has been reapproved for the treatment of acute myeloid leukemia (AML). AML patients with the

A suitable diagnostic classification of myeloid neoplasms and acute leukemias requires testing for a large number of molecular biomarkers. Next-generation sequencing is a technology able to integrate identification of the vast majority of them in a single test. This manuscript includes the design, analytical validation and clinical feasibility evaluation of a molecular diagnostic kit for onco-hematological diseases. It is based on sequencing of the coding regions of 76 genes (seeking single-nucleotide variants, small insertions or deletions and CNVs), as well as the search for fusions in 27 target genes. The kit has also been designed to detect large CNVs throughout the genome by including specific probes and employing a custom bioinformatics approach. The analytical and clinical feasibility validation of the Haematology OncoKitDx panel has been carried out from the sequencing of 170 patient samples from 6 hospitals (in addition to the use of commercial reference samples). The analytical validation showed sensitivity and specificity close to 100% for all the parameters evaluated, with a detection limit of 2% for SNVs and SVs, and 20% for CNVs. Clinically relevant mutations were detected in 94% of all patients. An analysis of the correlation between the genetic risk classification of AML (according to ELN 2017) established by the hospitals and that obtained by the Haematology OncoKitDx panel showed an almost perfect correlation (K = 0.94). Among the AML samples with a molecular diagnosis, established by the centers according to the WHO, the Haematology OncoKitDx analysis showed the same result in 97% of them. The panel was able to adequately differentiate between MPN subtypes and also detected alterations that modified the diagnosis (FIP1L1-PDGFRA). Likewise, the cytogenetic risk derived from the CNV plot generated by the NGS panel correlated substantially with the results of the conventional karyotype (K = 0.71) among MDS samples. In addition, the panel detected the main biomarkers of prognostic value among patients with ALL. This validated solution enables a reliable analysis of a large number of molecular biomarkers from a DNA sample in a single assay., This research was funded by Imegen (Instituto de Medicina Genómica, Paterna, Spain).

Treatment-free remission (TFR) in patients with chronic myeloid leukemia in chronic phase (CML-CP) is considered a feasible option, especially with the ability of second-generation tyrosine kinase inhibitors to induce higher rates of sustained deep molecular response (DMR). DASFREE is an open-label, single-arm, multicenter phase II trial assessing TFR after dasatinib discontinuation in patients with CML-CP (N = 84). At 2 years, TFR was 46% in all patients. Multivariate analyses revealed statistically significant associations between 2-year TFR and duration of prior dasatinib (≥median; p = .0051), line of therapy (first line; p = .0138), and age (>65 years; p = .0012). No disease transformation occurred, and the most common adverse events experienced off treatment were musculoskeletal (observed in 30 patients); however, dasatinib withdrawal events were reported in nine patients (11%) by the investigator. Overall, these findings support the feasibility of discontinuing dasatinib for patients with CML-CP in sustained DMR in the first line and beyond.

Background: Five-year follow-up of the open-label, phase 3 DASISION study (NCT00481247) demonstrated faster and deeper molecular responses with dasatinib versus imatinib as first-line therapy for CML-CP. NCCN guidelines recommend considering comorbidities when selecting first-line TKI therapy. This exploratory post hoc analysis of DASISION investigates the effect of comorbidities on responses with dasatinib versus imatinib. Design: Patients with newly diagnosed CML-CP were randomized to 100mg dasatinib (n=259) or 400mg imatinib (n=260) QD. Charlson Comorbidity Index (CCI) was retrospectively calculated for each patient at diagnosis; data were retrospectively stratified by CCI categories (2-4, 5-6, and ≥7 [high burden]). Major molecular response (MMR) and MR4.5 were compared between treatments using unstratified Cochran-Mantel-Haenszel tests. Time to response was evaluated using Kaplan-Meier methodology with HRs based on Cox proportional hazards models and P-values from unstratified log-rank tests. Results: Baseline characteristics were mostly balanced between treatments. Fourteen (3%) patients had CCI 2-4, 260 (50%) had 5-6, and 245 (47%) had ≥7. Responses were numerically greater with dasatinib versus imatinib for CCI 2-4 (MMR: 85.7% versus 57.1%, P=0.2542; MR4.5: 71.4% versus 14.3%, P=0.0374) and ≥7 (MMR: 70.8% versus 64.0%, P=0.2552; MR4.5: 45.0% versus 39.2%, P=0.3589), and significantly higher for CCI 5-6 (MMR: 81.1% versus 64.8%, P=0.0033; MR4.5: 42.4% versus 29.7%, P=0.0329). Median time to MMR (months) was significantly shorter with dasatinib than imatinib for CCI 5-6 (15.0 versus 24.0; HR, 1.64; P=0.0006) and ≥7 (12.0 versus 21.4; HR, 1.41; P=0.0279). Grade 3/4 treatment-related adverse events (TRAEs; dasatinib versus imatinib): 0% versus 14% (CCI 2-4), 8% versus 9% (CCI 5-6), 24% versus 13% (CCI ≥7). Frequency of grade 3/4 TRAEs leading to discontinuation was similar: 0% versus 0%, 1% versus 1%, 8% versus 7%. No deaths occurred for CCI 2-4; similar percentage of patients died between treatments for CCI 5-6 and ≥7. Conclusions: Dasatinib was effective across all CCI groups, consistent with previous findings, suggesting that comorbidities do not negatively affect TKI activity. These findings highlight the benefits of first-line dasatinib in patients with CML-CP and elevated comorbidity burden. Funding: Bristol Myers Squibb. Previous presentation: 62nd ASH Annual Meeting, December 5-8, 2020; republished with permission of Elsevier Inc.

Simple Summary: Dysregulation of noncoding RNAs has been described in numerous types of cancers and it has been associated with oncogenic or tumor suppressor activities. However, the signature of clinically relevant noncoding RNAs in pediatric B-cell acute lymphoblastic leukemia is still poorly understood. In a search for long non-coding RNAs that characterize pediatric B-cell acute lymphoblastic leukemia, we found that the long non-coding RNA AL133346.1 and a neighbouring protein-coding mRNA (CCN2) were significantly over-expressed in leukemia samples compared to healthy bone marrow. Survival analysis showed that patients with high CCN2 expression had a significantly better prognosis. These data suggest that AL133346.1/CCN2 could be useful for discriminating subtypes of leukemia and that CCN2 expression could predict the prognosis of pediatric patients with B-cell acute lymphoblastic leukemia. Abstract: Pediatric acute B-cell lymphoblastic leukemia (B-ALL) constitutes a heterogeneous and aggressive neoplasia in which new targeted therapies are required. Long non-coding RNAs have recently emerged as promising disease-specific biomarkers for the clinic. Here, we identified pediatric B-ALL-specific lncRNAs and associated mRNAs by comparing the transcriptomic signatures of tumoral and non-tumoral samples. We identified 48 lncRNAs that were di erentially expressed between pediatric B-ALL and healthy bone marrow samples. The most relevant lncRNA/mRNA pair was AL133346.1/CCN2 (previously known as RP11-69I8.3/CTGF), whose expression was positively correlated and increased in B-ALL samples. Their di erential expression pattern and their strong correlation were validated in external B-ALL datasets (Therapeutically Applicable Research to Generate E ective Treatments, Cancer Cell Line Encyclopedia). Survival curve analysis demonstrated that patients with “high” expression levels of CCN2 had higher overall survival than those with “low” levels (p = 0.042), and this gene might be an independent prognostic biomarker in pediatric B-ALL. These findings provide one of the first detailed descriptions of lncRNA expression profiles in pediatric B-ALL and indicate that these potential biomarkers could help in the classification of leukemia subtypes and that CCN2 expression could predict the survival outcome of pediatric B-cell acute lymphoblastic leukemia patients., Aula de Investigación sobre la Leucemia infantil: Héroes contra la Leucemia the Ministry of Economy of Spain SAF2015-67919-R, Junta de Andalucía PIGE-0440-2019 Pl-0245-2017 PI-0135-2020, University of Granada PPJIA2019-06 B-CTS-126-UGR18, Spanish Association for Cancer Research (LAB-AECC), Spanish Ministry of Education, Culture and Sports FPU fellowship FPU17/00067 FPU17/01258, PhD "La Caixa Foundation" fellowship LCF/BQ/DE15/10360019, Marie Sklodowska Curie Actions postdoctoral fellowship (H2020-MSCA-IF-2018), "Fundacion Benefica Anticancer Santa Candida y San Francisco Javier" predoctoral fellowship

The development of Next-Generation Sequencing (NGS) has provided useful diagnostic, prognostic, and therapeutic strategies for individualized management of B-cell precursor acute lymphoblastic leukemia (BCP-ALL) patients. Consequently, NGS is rapidly being established in clinical practice. However, the technology’s complexity, bioinformatics analysis, and the different available options difficult a broad consensus between different laboratories in its daily routine introduction. This collaborative study among Spanish centers was aimed to assess the feasibility, pros, and cons of our customized panel and other commercial alternatives of NGS-targeted approaches. The custom panel was tested in three different sequencing centers. We used the same samples to assess other commercial panels (OncomineTM Childhood Cancer Research Assay, Archer®FusionPlex® ALL, and Human Comprehensive Cancer Panel GeneRead Panel v2®). Overall, the panels showed a good performance in different centers and platforms, but each NGS approach presented some issues, as well as pros and cons. Moreover, a previous consensus on the analysis and reporting following international guidelines would be preferable to improve the concordance in results among centers. Our study shows the challenges posed by NGS methodology and the need to consider several aspects of the chosen NGS-targeted approach and reach a consensus before implementing it in daily practice.

Introduction: asciminib is a first-in-class STAMP (Specifically Targeting the ABL Myristoyl Pocket) inhibitor that potently inhibits aberrant kinase activity of the BCR-ABL1 oncoprotein via allosteric binding. asciminib has shown high efficacy profile in heavily pretreated Chronic Myeloid Leukemia (CML) patients with an adequate safety profile in phase I and III clinical trials. However, data from the use of asciminib in real life setting are still scarce. Methods: We gathered real-life retrospective data from 49 patients with BCR-ABL1 positive CML treated with asciminib (mean dose: 40 mg twice daily) between October 2018 and July 2021 at 33 institutions. The indication of asciminib was made according to the criterion of the attending physician and the drug was granted by Novartis under a controlled access program. Molecular biology tests were performed according to ELN guidelines and BCR-ABL/ABL ratios were expressed as % IS in all centers. Treatment responses were calculated with the patients at risk at each specific time points. For the event free survival (EFS), the events were treatment discontinuation due to any reason, progression or death. Data collection followed the local regulations for observational studies. Results: Median time on asciminib was 11,69 months for the entire cohort. Patients' characteristics are displayed on Table 1. Most patients were heavily pretreated with at least 3 prior TKI lines in 45 patients (91,83%), 18 of them receiving prior Ponatinib. Switch to asciminib occurred due to intolerance in 32 patients and due to resistance in the remaining 17. Fifteen patients (30,61%) harbored mutations in BCR-ABL1 (3 with a T315 mutation). Regarding efficacy (Table 2), probability of reaching or maintaining previous responses were 94%, 45% and 21% for complete hematological response (CHR), complete cytogenetic response (CCyR) and major molecular response (MMR), respectively. Considering probabilities of improving previous response, rates were 40%, 42% and 33% for the same parameters. Probabilities to obtain CCyR and MMR in resistant and intolerant patients were 29% (4/14) vs 55% (6/11) and 27% (4/15) vs 52% (11/21), respectively. Amid the patients previously treated with Ponatinib, probabilities of reaching or maintaining previous response were 53% (9/17) and 35% (6/17) for CCyR and MMR respectively, and 30% (3/10), 23% (3/13) displayed improvement of response. Regarding responses in patients with mutations, 39% (5/13) achieved or maintained CCyR and 31% (4/13) MMR; whereas 20% (2/10) and 18% (2/11) improved such responses. Of the three patients with T315I mutation, one discontinued due to progression to advanced stages, and the rest maintained the previous response. With a median follow-up of 11,69 months, the estimated EFS was 80% (figure 1). In terms of safety (Table 3), the most frequent extra-hematological adverse events (AE) were: fatigue (16,2%), joint pain (13,5%) and nausea (8,1%), most of them grade 1-2. Grade 3-4 AE were observed in 10% of patient (fatigue (2), cholestasis enzyme elevation (1), hypertension (1), pancreatitis (1) and pericardial effusion (1)). Thrombocytopenia was shown as the most frequent AE (16,3%), with 6% of patients suffering from grade 3-4. Dose reduction was required in 15 patients (30,6%). After a median follow up of 51 weeks, 73,5% of the patients remained on treatment. Only fourteen patients discontinued treatment due to progression or loss of efficacy, whereas 6% of patients discontinuing treatment due to intolerance. Conclusions: The results presented are in line with the data obtained in clinical trials, positioning asciminib as a potential safe and efficacious treatment for CML patients with failure to several TKI lines. Figure 1 Figure 1. Disclosures Sanchez-Guijo: Novartis: Consultancy, Honoraria, Research Funding; Celgene/Bristol-Myers-Squibb,: Consultancy, Honoraria; Incyte: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Takeda: Honoraria, Research Funding; Roche: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; Amgen: Consultancy, Honoraria. Garcia Gutierrez: BMS: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; Incyte: Consultancy, Honoraria, Research Funding.

Introduction: Tyrosine kinase inhibitors (TKIs) have dramatically improved the standard of care for patients (pts) with chronic myeloid leukemia in chronic phase (CML-CP). In the 5-year follow-up of the phase 3 DASISION study (NCT00481247), dasatinib was associated with faster and deeper molecular responses than imatinib as first-line therapy for CML-CP (Cortes J et al. J Clin Oncol 2016). The NCCN guidelines recommend that multiple factors independent of risk score should be considered when selecting TKI therapy, including the presence of comorbidities. More than 50% of pts with CML-CP have at least one comorbidity at diagnosis (Hoffmann et al. Leukemia 2015); as such, comorbidities may influence first-line treatment choice for most pts. In this exploratory post hoc analysis of DASISION at 5-years' follow-up, we investigated the effect of comorbidities on response outcomes with dasatinib vs imatinib. Methods: DASISION was a multinational, open-label, phase 3 trial assessing dasatinib vs imatinib for newly diagnosed CML-CP. Pts were randomized to receive 100 mg dasatinib (n = 259) or 400 mg imatinib (n = 260) once daily. Charlson Comorbidity Index (CCI) was retrospectively calculated for each pt at diagnosis. Efficacy and safety data were retrospectively stratified based on CCI score categories 2-4, 5-6, and ≥ 7 (higher scores indicate a higher comorbidity burden). Rates of major molecular response (MMR) and molecular response with a 4.5-log reduction (MR4.5) were compared between treatment groups using unstratified Cochran-Mantel-Haenszel tests. Time to MMR and MR4.5 were evaluated using Kaplan-Meier methodology with hazard ratios (HRs) based on Cox proportional hazards models and P values from unstratified log-rank tests. Confidence intervals (CI) for median time to response were calculated using the Brookmeyer and Crowley method. P values are descriptive and unadjusted for multiple comparisons. Results: In total, 14 (3%) pts had CCI 2-4 (dasatinib 7, imatinib 7), 260 (50%) had CCI 5-6 (dasatinib 132, imatinib 128), and 245 (47%) had CCI ≥ 7 (dasatinib 120, imatinib 125). Baseline characteristics and drug exposure data are shown in the Table. Dose reductions of dasatinib and imatinib occurred in 14% vs 29% (CCI 2-4 group), 23% vs 12% (CCI 5-6 group) and 54% vs 22% (CCI ≥ 7 group) of pts, respectively. In the CCI 2-4 group, the MMR rate was 85.7% with dasatinib and 57.1% with imatinib (P = 0.2542) and the MR4.5 rates were 71.4% and 14.3% (P = 0.0374), respectively. In the CCI 5-6 group, the MMR rate was significantly higher with dasatinib vs imatinib (81.1% vs 64.8%, P = 0.0033), as was the MR4.5 rate (42.4% vs 29.7%, P = 0.0329). Median time to MMR in the CCI 5-6 group was significantly shorter with dasatinib than imatinib (15.0 vs 24.0 months; HR, 1.64; 95% CI, 1.23-2.19; P = 0.0006). In the CCI ≥ 7 group, response rates were numerically higher with dasatinib than imatinib: MMR rates were 70.8% vs 64.0% (P = 0.2552) and MR4.5 rates were 45.0% vs 39.2% (P = 0.3589), respectively. Median time to MMR was significantly shorter in the CCI ≥ 7 group with dasatinib than imatinib (12.0 vs 21.4 months; HR, 1.41; 95% CI, 1.04-1.91; P = 0.0279; Figure). Grade 3-4 treatment-related adverse events (TRAEs) were reported in 0% vs 14% (dasatinib vs imatinib) of pts with CCI 2-4, 8% vs 9% of pts with CCI 5-6, and 24% vs 13% of pts with CCI ≥ 7. Grade 3-4 TRAEs leading to discontinuation did not occur in the CCI 2-4 group, and were reported with similar frequency with dasatinib and imatinib in both CCI 5-6 (1% vs 1%) and CCI ≥ 7 groups (8% vs 7%). No deaths occurred in the CCI 2-4 group; a similar percentage of pts treated with dasatinib and imatinib died in the CCI 5-6 group (8% vs 9%) and CCI ≥ 7 group (13% vs 11%). Conclusions: In this exploratory post hoc analysis, dasatinib was effective across all CCI groups, consistent with previous findings suggesting that comorbidities do not negatively affect TKI activity. Molecular response rates were significantly higher with dasatinib than imatinib in pts with CCI 5-6, and comparable between treatments in pts with CCI ≥ 7. Furthermore, time to response was significantly faster with dasatinib than imatinib in both the CCI 5-6 and CCI ≥ 7 groups, while the frequency of grade 3-4 TRAEs leading to discontinuation was similar between treatments. These findings highlight the benefit of first-line treatment with dasatinib in pts with CML-CP and a high comorbidity burden. Study support: BMS. Figure Disclosures Breccia: Bristol-Myers Squibb/Celgene: Consultancy, Honoraria; Abbvie: Consultancy; Pfizer: Consultancy, Honoraria; Incyte: Consultancy, Honoraria; Novartis: Consultancy, Honoraria. Mauro:Sun Pharma/SPARC: Research Funding; Pfizer: Consultancy, Honoraria, Other: Travel, Accommodation, Expenses, Research Funding; Takeda: Consultancy, Honoraria, Other: Travel, Accommodation, Expenses, Research Funding; Novartis: Consultancy, Honoraria, Other: Travel, Accommodation, Expenses, Research Funding; Bristol-Myers Squibb: Consultancy, Honoraria, Other: Travel, Accommodation, Expenses, Research Funding. Jabbour:BMS: Other: Advisory role, Research Funding; Takeda: Other: Advisory role, Research Funding; Pfizer: Other: Advisory role, Research Funding; Adaptive Biotechnologies: Other: Advisory role, Research Funding; Genentech: Other: Advisory role, Research Funding; Amgen: Other: Advisory role, Research Funding; AbbVie: Other: Advisory role, Research Funding. Saglio:Pfizer: Research Funding; Bristol-Myers Squibb: Research Funding; Incyte: Research Funding; Roche: Research Funding; Ariad: Research Funding; Novartis: Research Funding. le Coutre:Pfizer: Honoraria; Novartis: Honoraria; Incyte: Honoraria. DeGutis:Bristol-Myers Squibb: Current Employment, Current equity holder in publicly-traded company. Khan:Bristol-Myers Squibb: Current Employment, Current equity holder in publicly-traded company. Sy:Bristol-Myers Squibb: Current Employment. Swanink:Bristol-Myers Squibb: Current Employment. Cortes:Amphivena Therapeutics: Research Funding; Novartis: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; Daiichi Sankyo: Consultancy, Research Funding; Jazz Pharmaceuticals: Consultancy, Research Funding; Immunogen: Research Funding; Merus: Research Funding; Bristol-Myers Squibb: Research Funding; Arog: Research Funding; BiolineRx: Consultancy, Research Funding; BioPath Holdings: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Astellas: Research Funding; Telios: Research Funding; Sun Pharma: Research Funding.

BackgroundThe analysis of molecular haematopoietic chimerisms (HC) has become a well-established method to monitor the transplant evolution and to assess the risk of relapse after allogeneic stem cells transplantation (allo-STC). Different techniques and molecular markers are being used for chimerism surveillance after transplantation, including quantitative real-time PCR (qPCR) and the recently developed digital PCR (dPCR). This study aims to compare the sensitivity and accuracy of both methods to quantify HC and predict early relapse.MethodologyHC was evaluated using custom PCR systems for the specific detection of the Y-chromosome, null alleles and insertion-deletion polymorphisms. A total of 281 samples from 28 adult patients who underwent an allo-SCT were studied. Increasing mixed chimerism was detected prior to relapse in 100% of patients (18 relapses).ResultsCompared with conventional qPCR amplification, dPCR predicted relapse with a median anticipation period of 63 days versus 45.5 days by qPCR. Overall, 56% of the relapses were predicted earlier with dPCR whereas 38% of the relapses where detected simultaneously using both techniques and only in 1 case, relapse was predicted earlier with qPCR.ConclusionsIn conclusion, chimerism determination by dPCR constitutes a suitable technique for the follow-up of patients with haematological pathologies after allo-STC, showing greater sensitivity to predict an early relapse.

To determine whether a lower imatinib dose could minimize toxicity while maintaining the molecular response (MR), imatinib dose was reduced to 300 mg daily in 43 patients with chronic myeloid leukemia (CML) in sustained deep molecular response to first-line imatinib 400 mg daily. At the time of dose reduction, median duration of the deep response was 4.1 (interquartile range (IQR) 2.2–5.9) years; molecular response was MR4, MR4.5, and MR5 of the international scale in 6, 28, and 9 patients, respectively. Toxicity grade was 1, 2, and 3 in 28, 8, and 1 patients, respectively; 6 patients underwent dose reduction without having side effects. With a median of 1.6 (IQR 0.7–3.2) years on imatinib 300 mg daily, only one patient lost the deep molecular response to MR3. At the last follow-up, response was MR3, MR4, MR4.5, and MR5 in 1, 3, 9, and 30 patients, respectively. Toxicity improvement was observed in 23 (62.2 %) of the 37 patients with side effects, decreasing to grade 0 in 20 of them. All but one anemic patients improved (p = 0.01), the median Hb increase in this subgroup of patients being 1 g/dL. In CML patients with sustained deep response to the standard imatinib dose, reducing to 300 mg daily significantly improves tolerability and preserves efficacy.

Context In the treatment of CML-CP, early molecular responses to tyrosine kinase inhibitors (TKIs) are associated with improved long-term outcomes, and major molecular response (MMR) at 18 months is an important goal. Obesity may elevate the risk of CML (Strom 2009), and high BMI at diagnosis can delay time to response and reduce MMR rate in patients treated with first-line imatinib (Breccia 2013). In the phase 3 DASISION study ( NCT00481247 ), dasatinib was associated with earlier, more durable, and deeper responses than imatinib (Cortes 2016). Objective Investigate the relationship between BMI and response to first-line TKIs. Design DASISION was an open-label multinational study assessing dasatinib versus imatinib for newly diagnosed CML-CP. Patients were randomized to 100mg dasatinib or 400mg imatinib once daily. In this exploratory analysis, patients were stratified according to high (≥25kg/m2) or normal BMI ( Results Collectively, 259 patients received dasatinib (high BMI, n=109; normal BMI, n=147; unknown, n=3) and 260 received imatinib (high BMI, n=107; normal BMI, n=147; unknown, n=6). Baseline characteristics were balanced within BMI subgroups. High BMI subgroup: significant improvements for dasatinib versus imatinib in median time to MMR (9.2 vs 27.6 months; P Conclusions Improved outcomes were seen in patients with high BMI treated with dasatinib versus imatinib; however, these differences were not seen with normal BMI. These findings need further validation to ascertain the role of BMI in predicting treatment responses in patients with CML-CP. Funding BMS. Previous presentation ASH 2019, HOPA 2020.

Bosutinib is a second-generation tyrosine kinase inhibitor (2GTKI) approved at 400 mg once daily (QD) as first-line therapy in patients with chronic myeloid leukemia (CML) patients and at 500 mg QD in patients who are resistant to or intolerant of prior therapy. In clinical practice, bosutinib is often given to patients who have failed imatinib, nilotinib, and dasatinib (i.e., as fourth-line treatment), despite the limited data on its clinical benefit in this setting. We have retrospectively evaluated the results of bosutinib in a series of 62 CML patients who have failed to prior treatment with all three, imatinib, nilotinib, and dasatinib. Median time on TKI treatment before bosutinib start was 105 (9–163) months, and median duration on bosutinib was 9 months (1–30). Overall, probabilities to achieve complete cytogenetic response (CCyR) and major molecular response (MMR) were 25% and 24% respectively. After a median follow-up period of 14 months, the event-free survival and progression-free survival were 68 and 85%, respectively. Sixty-four percent of patients in CCyR at the time of bosutinib start were able to achieve MMR. In contrast, patients without CCyR, probabilities to obtain CCyR and MMR were 25% and 14%. Bosutinib was well tolerated in this heavily pretreated patients’ cohort. Pleural effusions and diarrhea were the most frequent grade II–IV side effects, leading to treatment discontinuation in 16% of patients. Bosutinib is an effective treatment option for patients who have failed previous 2GTKIs due to intolerance. However, efficacy seems to be related to the molecular response that the patient achieved prior to bosutinib.

Programmed death 1 (PD-1) activation triggers an immune checkpoint resulting in inhibition of T cells that leads to peripheral tolerance. Some PD-1 polymorphisms have been described and associated with the development of autoimmune diseases or cancer predisposition, but there are few data concerning the relevance of such polymorphisms on the clinical outcome after allogeneic hematopoietic stem cell transplant (alloHSCT). We analyzed the distribution of the SNPs PD-1.1G/A (rs36084323) and PD-1.3G/A (rs11568821) genotypes of the donor in a cohort of 1485 alloHSCT from HLA-identical sibling donors. We found an increased risk of grades II to IV graft-versus-host disease (GvHD) in patients receiving grafts from donors homozygous for the G allele at the rs36084323 SNP (P = 0.033; hazard ratio [HR] 2.2; 95% confidence interval [CI] 1.1 to 4.8) and also from donors homozygous for the A allele at the rs11568821 position (P

Introduction: Early responses to tyrosine kinase inhibitors (TKIs) are associated with improved long-term outcomes in patients with chronic myeloid leukemia in chronic phase (CML-CP), and guideline recommendations support the achievement of major molecular response (MMR) at 18 months as a therapeutic goal in CML treatment. Dasatinib is a first-line (1L) treatment option for patients with CML-CP, and long-term results from the DASISION study have demonstrated that patients on dasatinib achieved faster, deeper, and more durable molecular responses than patients on imatinib (Cortes J et al. J Clin Oncol 2016). Earlier reports have shown that obesity may increase the risk of developing CML (Strom SS et al. Cancer Epidemiol Biomarkers Prev 2009) and that patients with a high body mass index (BMI; > 25 kg/m2) at diagnosis who receive 1L imatinib have a significantly longer median time to response and a reduced rate of MMR compared with patients with a normal BMI (< 18.5-25 kg/m2; Breccia M et al. Cancer Lett 2013). In this exploratory post hoc analysis of the phase 3 DASISION trial (NCT00481247), we further investigated the association of high BMI with treatment responses with 1L TKIs. Methods: DASISION was a multinational, open-label, phase 3 trial of dasatinib versus imatinib for newly diagnosed CML-CP. Patients were randomized to receive 100 mg dasatinib (n = 259) or 400 mg imatinib (n = 260) once daily. Response outcomes were retrospectively stratified on the basis of two BMI categories: high (≥ 25 kg/m2) and normal (< 25 kg/m2). Median time to response was estimated using Kaplan-Meier analysis; Cox proportional hazard models and log-rank tests were stratified by Hasford scores. Molecular response rates were compared using Cochran-Mantel-Haenszel tests (stratified by Hasford scores). P values are descriptive and unadjusted for multiple comparisons. Results: In total, 109 patients with a high BMI and 147 patients with a normal BMI were treated with dasatinib, and 107 patients with a high BMI and 147 patients with a normal BMI were treated with imatinib. Baseline characteristics were balanced within BMI subgroups and are listed in the table below (Table). Median time to complete cytogenetic response (CCyR) was significantly shorter with dasatinib versus imatinib in patients with a high BMI (3.1 vs 6.1 months; P < 0.0001). MMR was also achieved faster in patients with a high BMI who were treated with dasatinib versus imatinib (median time 9.2 vs 27.6 months; P < 0.0001; Figure). More patients with a high BMI treated with dasatinib achieved MMR compared with those treated with imatinib (79.8% vs 59.8%; P = 0.0004). Likewise, 54.1% of patients with a high BMI achieved MR4.5 with dasatinib, compared with 34.6% with imatinib (P = 0.0013). In the normal BMI group, median time to CCyR (5.6 vs 6.0 months; P = 0.1055) and MMR (18.0 vs 21.5 months; P = 0.4095) was faster for dasatinib versus imatinib, and more patients on dasatinib versus imatinib achieved MMR (73.5% vs 67.3%; P = 0.3335) and MR4.5 (36.7% vs 33.3%; P = 0.6344). Although these results were numerically better with dasatinib, the differences were not statistically different. A graphical exploratory analysis suggested that there was no difference in exposures across BMI subgroups with respect to dasatinib. However, imatinib exposure data were not available to make comparisons across the BMI subgroups. There was no major difference in the previously reported adverse event profiles between treatment groups when assessed based on BMI. Any-cause pleural effusion occurred more frequently with dasatinib (34.3% [high BMI] and 24.5% [normal BMI]) compared with imatinib (0% [high BMI] and 2.0% [normal BMI]). Additional analyses are being planned to address the role of any potential confounders (eg, Hasford risk scores). Conclusions: In this exploratory post hoc analysis, patients with a high BMI treated with dasatinib demonstrated a significantly faster time to response compared with imatinib, with an increased percentage of patients also achieving MMR and MR4.5 at 5 years. However, these differences were not apparent in patients with a normal BMI. Although these findings highlight the potential role of BMI in affecting treatment responses to TKIs, additional validation of these findings is necessary to define the overall impact of BMI as a prognostic factor for patients with CML-CP. Study support: BMS. Writing support: Jane Cheung, Caudex, funded by BMS. Disclosures Breccia: Bristol-Myers Squibb, Celgene, Incyte, Novartis, Pfizer: Honoraria. Cortes:Bristol-Myers Squibb: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Daiichi Sankyo: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; Astellas Pharma: Consultancy, Honoraria, Research Funding; Jazz Pharmaceuticals: Consultancy, Research Funding; Sun Pharma: Research Funding; Immunogen: Consultancy, Honoraria, Research Funding; Merus: Consultancy, Honoraria, Research Funding; Forma Therapeutics: Consultancy, Honoraria, Research Funding; Biopath Holdings: Consultancy, Honoraria; BiolineRx: Consultancy. Shah:Bristol-Myers Squibb: Research Funding. Saglio:Celgene: Consultancy; Jansen: Consultancy; Pfizer: Consultancy; BMS: Consultancy; Novartis: Consultancy; Ariad: Consultancy; Incyte: Consultancy. Le Coutre:Novartis: Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau; Bristol-Myers Squibb: Honoraria, Speakers Bureau; Incyte: Honoraria, Speakers Bureau. Brun:Bristol-Myers Squibb: Employment. DeGutis:Bristol-Myers Squibb: Employment, Other: Stock options. Sy:Bristol-Myers Squibb: Employment, Equity Ownership. Jabbour:AbbVie: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; BMS: Consultancy, Research Funding; Adaptive: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Cyclacel LTD: Research Funding; Pfizer: Consultancy, Research Funding.

The level of BCR-ABL1 reached after treatment with tyrosine kinase inhibitors is an effective marker of the therapeutic response and a good survival predictor in chronic myeloid leukemia (CML) patients. However, no agreement has yet been achieved about either the standardization of the technique to determine BCR-ABL1 or the interpretation of the results. The aim of this study was to compare the method currently recommended by the European Leukemia Net, which includes the application of a conversion factor to express the results in international scale, with an automated method (Xpert BCR-ABL™, Cepheid). BCR-ABL1 transcript quantification was performed in 117 samples from CML patients in two different laboratories by both methods, and the results were compared by statistical procedures. A high linear correlation was obtained in the results between the two methods. The concordance at logarithmic intervals reached 62 %. When the major molecular response (MMR) was analyzed, 85 % agreement was achieved. The automated method provides reproducible results and does not show significant differences compared with the traditional method. As a clinical tool, Xpert correctly classified the patients in MMR and can be considered a useful alternative for the molecular follow-up of CML patients.

Introduction: Tyrosine kinase inhibitor (TKI) discontinuation is being investigated in pts with CML-CP with sustained DMR (defined here as MR4.5 or BCR-ABL1 ≤ 0.0032% on the International Scale [IS]), with the goal of treatment-free remission (TFR). Successful TFR has been reported previously for pts enrolled in DASFREE (CA180-406/NCT01850004), which showed that 48% of CML-CP pts with DMR for ≥ 1 year were able to stop dasatinib and maintain major molecular response (MMR) 12 months after discontinuation. Here we present updated results from pts followed for a minimum of 18 months, in order to understand the durability of TFR beyond 12 months. Methods: DASFREE is a phase 2, open-label, single-arm study in adult pts with CML-CP on dasatinib for ≥ 2 years as 1st-line or subsequent therapy. Eligible pts had dasatinib-induced DMR (MR4.5) confirmed at a local lab for ≥ 1 year prior to enrollment, with a 1-log reduction in BCR-ABL1 from baseline within 3-6.5 months of starting dasatinib. MR4.5 was confirmed at a central lab twice within 3 months prior to dasatinib discontinuation (screening phase). BCR-ABL1 was monitored centrally after discontinuation every month in the 1st year, then every 3 months. Pts resumed dasatinib at their previous dose if MMR was lost. The primary endpoint is the rate of MMR 12 months after dasatinib discontinuation. Secondary endpoints include BCR-ABL1 kinetics, molecular relapse-free survival (MRFS; no loss of MMR), relapse-free survival (RFS; no loss of MMR, complete cytogenetic response, or complete hematologic response, or progression to accelerated/blast phase [AP/BP] CML), rate of transformation to AP/BP, progression-free survival, and overall survival. Exploratory analyses include frequency of adverse events (AEs) after discontinuation and during dasatinib treatment, and MMR after reinitiating dasatinib. Results: In total, 84 pts enrolled between February 2014 and June 2016 discontinued dasatinib; all had ≥ 18 months of follow-up after discontinuation at the time of this analysis. Pt characteristics were previously reported (the majority [64%] had low Sokal scores; no pt had prior interferon; 37 pts were on 1st-line dasatinib, 47 on subsequent lines of dasatinib). At 18 months after discontinuation, the RFS rate was 48% (95% CI 37-58) in all pts (Figure), 54% (95% CI 38, 70) in 1st-line pts, and 42% (95% CI 28, 57) in pts who received subsequent-line therapy. With longer follow-up, 1 additional pt lost MMR at 18 months following discontinuation. Of the 45 pts who lost MMR and restarted treatment, 44 regained MMR (1 pt discontinued after only 1 molecular assessment) in a median of 2 months (range 1-4) and 42 regained MR4.5 in a median of 3 months (range 2-18). Analyses of baseline pt characteristics revealed that for the 40 pts who did not lose MMR after discontinuation, 15 (37.5%) were able to maintain MR4.5. Additionally, the median time in prior MR4.5 was 28 months (range 13-116) for all pts, and was similar for 1st-line pts who maintained (27 months [range 13-56]) or lost MMR (27 months [range 15-68]) at 12 months. With longer follow-up, AEs (any cause) identified were consistent with previous reports and were found to be similar on and off treatment: 8 (10%) pts off treatment and 8 (18%) pts on treatment experienced grade 3/4 AEs of any cause after restarting dasatinib (4.4% were drug related). No transformation events or deaths occurred. Of the 13 reported withdrawal events occurring in 8 (9.5%) pts, 10 were resolved (5 off treatment, 5 resolved after restarting treatment due to loss of MMR) after a median of 5 months (range 1-12) after onset. One pt discontinued after restarting dasatinib due to malignancy unrelated to treatment. In addition to efficacy and safety data, multivariate analyses evaluating prognostic factors for MMR will be presented. Conclusions: Additional follow-up of pts enrolled in DASFREE revealed that TFR remained durable at 18 months after discontinuing dasatinib. AEs reported here were consistent with the known safety profile of dasatinib, and withdrawal was well tolerated. Collectively, this trial, the largest dasatinib discontinuation trial to date, continues to support the feasibility and practicality of TFR in pts with CML-CP in DMR treated with dasatinib in the 1st line and beyond. Figure. Figure. Disclosures Shah: ARIAD: Research Funding; Bristol-Myers Squibb: Research Funding. García Gutiérrez:Bristol-Myers Squibb: Consultancy, Research Funding, Speakers Bureau; Incyte: Consultancy, Research Funding, Speakers Bureau; Novartis: Consultancy, Research Funding, Speakers Bureau. Larson:Bristol-Myers Squibb: Consultancy; Takeda: Speakers Bureau. Saussele:Bristol-Myers Squibb: Honoraria, Research Funding; Incyte: Honoraria; Novartis: Honoraria, Research Funding; Pfizer: Honoraria. Rea:Incyte: Honoraria; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria. Mahon:Bristol-Myers Squibb: Speakers Bureau; Incyte: Speakers Bureau; Novartis: Speakers Bureau; Pfizer: Speakers Bureau. Levy:Takeda (Millennium Pharmaceuticals, Inc.): Consultancy. Gómez-Casares:Novartis: Speakers Bureau; Bristol-Myers Squibb: Speakers Bureau; Incyte: Speakers Bureau. Pane:Bristol-Myers Squibb: Consultancy, Honoraria; Novartis: Consultancy, Honoraria, Research Funding; Incyte: Consultancy. Nicolini:Incyte: Consultancy, Honoraria, Speakers Bureau; Sun Pharma: Consultancy; Bristol-Myers Squibb: Consultancy, Honoraria, Speakers Bureau. Mauro:Pfizer: Consultancy; Takeda: Consultancy; Bristol-Myers Squibb: Consultancy; Novartis: Consultancy, Research Funding. Sy:Bristol-Myers Squibb: Employment. Martin Regueira:Bristol-Myers Squibb: Employment, Equity Ownership. Lipton:ARIAD: Consultancy, Research Funding; Bristol-Myers Squibb: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Pfizer: Consultancy, Research Funding.

This study aimed to compare the sensitivity and accuracy of two methods of quantitative real-time polymerase chain reaction (qrt-PCR), in order to determine haematopoietic chimerism (CH): single nucleotide polymorphisms using TaqMan (TM) probes and insertion/deletion polymorphisms using Hybridization (Hyb) probes. A total of 106 samples from 20 patients who underwent allogenic stem cell transplantation (n = 14) or live-donor liver transplantation (n = 6) were studied. The mean level of chimerism was 8.37% for the TM method and 7.73% in the Hyb method, which was not significantly different (P = 0.69). The Pearson correlation coefficient between the two methods was r = 0.91 (P < 0.001). The estimation of the regression line, using the Passing and Balbock method was Intercept A -0.0381 [95% confidence interval (CI) -0.1265 to 0.0296) and Slope B: 1.04609(95% CI 0.9349-1.161). Bland-Altman data showed that the standard deviations, which differed between the two methods (%Hyb-%TM), were 0.98 and -1.28. The accuracy and sensitivity of qrt-PCR chimerism is independent of the method used if the optimization is adequate and satisfies the criteria for adequate study. Real-time PCR, independent of the method adopted, is a very good tool for study levels of CH.

Background Expression of the pro-apoptotic BCL-2-interacting mediator ( BIM ) has recently been implicated in imatinib-induced apoptosis of BCR-ABL1 + cells. However, the mechanisms involved in the regulation of BIM in CML and its role in the clinical setting have not been established. Design and methods We analysed the mRNA expression of BIM in 100 newly diagnosed patients with CML in chronic phase by Q-RT-PCR and the protein levels by Western blot analysis. Methylation status was analysed by bisulphite genomic sequencing and MSP. CML cell lines were treated with imatinib and 5-aza-2’-deoxycytidine, and were transfected with two different siRNAs against BIM and cell proliferation and apoptosis were analysed. Results We demonstrated that down-regulation of BIM expression was present in 36% of the patients and was significantly associated with a lack of optimal response to imatinib as indicated by the decrease in cytogenetic and molecular responses at 6, 12 and 18 months in comparison with patients with normal BIM expression ( p BIM was mediated by promoter hypermethylation as demonstrated by restoration of BIM expression after treatment of CML cells with 5-aza-2′-deoxycytidine. Using CML cell lines with low and normal expression of BIM we further demonstrated that the expression of BIM is required for imatinib-induced CML apoptosis. Conclusion Our data indicate that down-regulation of BIM is epigenetically controlled by methylation in a percentage of CML patients and has an unfavourable prognostic impact, and that the combination of imatinib with a de-methylating agent may result in improved responses in patients with decreased expression of BIM .

MicroRNAs (miRNA) are small noncoding, single-stranded RNAs that inhibit gene expression at a posttranscriptional level, whose abnormal expression has been described in different tumors. The aim of our study was to identify miRNAs potentially implicated in chronic myeloid leukemia (CML). We detected an abnormal miRNA expression profile in mononuclear and CD34+ cells from patients with CML compared with healthy controls. Of 157 miRNAs tested, hsa-miR-10a, hsa-miR-150, and hsa-miR-151 were down-regulated, whereas hsa-miR-96 was up-regulated in CML cells. Down-regulation of hsa-miR-10a was not dependent on BCR-ABL1 activity and contributed to the increased cell growth of CML cells. We identified the upstream stimulatory factor 2 (USF2) as a potential target of hsa-miR-10a and showed that overexpression of USF2 also increases cell growth. The clinical relevance of these findings was shown in a group of 85 newly diagnosed patients with CML in which expression of hsa-miR-10a was down-regulated in 71% of the patients, whereas expression of USF2 was up-regulated in 60% of the CML patients, with overexpression of USF2 being significantly associated with decreased expression of hsa-miR-10a (P = 0.004). Our results indicate that down-regulation of hsa-miR-10a may increase USF2 and contribute to the increase in cell proliferation of CML implicating a miRNA in the abnormal behavior of CML. (Mol Cancer Res 2008;6(12):1830–40)

The clinical significance of aberrant promoter methylation of the canonical Wnt pathway antagonist genes (sFRP1, sFRP2, sFRP4, sFRP5, Wif1, Dkk3, and Hdpr1) and also putative tumor-suppressor gene Wnt5a, belonging to the non-canonical Wnt signaling pathway, was investigated in a large series of 75 patients with Philadelphia chromosome-positive acute lymphoblastic leukemia by methylationspecific polymerase chain reaction. At least one methylated gene was observed in cells from 66% (49/75) of patients (methylated group). Disease-free survival and overall survival at 9 years were 51 and 40%, respectively, for the unmethylated group and 3 and 2%, respectively, for the methylated group (both P < 0.0001). Multivariate analysis demonstrated that the Wnt methylation profile was an independent prognostic factor predicting disease-free survival (P = 0.007) and overall survival (P = 0.039). Abnormal DNA methylation of promoter-associated CpG islands in the Wnt signaling pathway is very common in Philadelphia chromosome-positive acute lymphoblastic leukemia and potentially defines subgroups with distinct clinical characteristics.

In order to determine new signal transduction pathways implicated in chronic myeloid leukaemia (CML), we performed a gene expression profile comparison between CD34+ cells from CML patients and healthy donors. Functional studies were performed using the Mo7e and Mo7e-p210 cell lines. Expression of CCND1 (Cyclin D1), as well as the chaperone HSPA8, which is important for regulation of CCND1, were significantly upregulated in CD34+ CML cells. Upregulation of HSPA8 was dependent, at least in part, on STAT5 (signal transducer and activator of transcrition 5)-dependent transcriptional activation, as demonstrated by chromatin immunoprecipitation. The presence of HSPA8 in the nuclear protein fraction as well as its binding to CCND1 suggests that it may contribute to stabilization of the CCND1/CDK4 complex, which, in turn, may participate in proliferation of CML cells. Treatment of CML cells with the specific HSPA8 inhibitor 15-deoxyspergualin induced inhibition of CML cell viability but did not induce apoptosis. In conclusion, our studies suggest that STAT5-mediated activation of HSPA8 induces nuclear translocation and activation of the CCND1/CDK4 complex leading to increased proliferation of CML cells, deciphering a new pathway implicated in CML and supporting a potential role of chaperone inhibitors in the treatment of CML.

The aim of our study was to determine the potential mechanism(s) implicated in Imatinib resistance in patients with Ph + ALL. Resistance of Ph + ALL cells to Imatinib-induced apoptosis was associated with lack of inhibition of Akt phosphorylation. Addition of the PI3K inhibitor LY294002 to Imatinib significantly increased apoptosis of Ph + ALL cells. Interestingly, expression of PTEN was reduced in Ph + ALL cells which was due to PTEN promoter hypermethylation. Treatment of Ph + ALL cells with 5-Aza-2′-deoxycytidine was associated with an increased expression of PTEN and an increase in cell apoptosis. These results suggest that Imatinib resistance in patients with ALL may be dependent at least in part to PTEN down-regulation due to the abnormal promoter hypermethylation and support the potential role of de-methylating agents for the treatment of patients with Ph + ALL.

CTLA-4 is an inhibitory molecule that down-regulates T-cell activation. Although polymorphisms at CTLA-4 have been correlated with autoimmune diseases their association with clinical outcome after allogeneic hematopoietic stem cell transplantation (allo-HSCT) has yet to be explored. A total of 5 CTLA-4 single-nucleotide polymorphisms were genotyped on 536 HLA-identical sibling donors of allo-HSC transplants. Genotypes were tested for an association with patients' posttransplantation outcomes. The effect of the polymorphisms on cytotoxic T-lymphocyte antigen 4 (CTLA-4) mRNA and protein production were determined in 60 healthy control participants. We observed a reduction in the mRNA expression of the soluble CTLA-4 isoform in the presence of a G allele at CT60 and +49. Patients receiving stem cells from a donor with at least 1 G allele in position CT60 had worse overall survival (56.2% vs 69.8% at 5 years; P = .001; hazard ratio [HR], 3.80; 95% confidence interval [CI], 1.75-8.22), due to a higher risk of relapse (P = .049; HR, 1.71; 95% CI, 1.00-2.93). Acute graft-versus-host disease (aGVHD) was more frequent in patients receiving CT60 AA stem cells (P = .033; HR, 1.54; 95% CI, 1.03-2.29). This is the first study to report an association between polymorphisms at CTLA-4 and clinical outcome after allo-HSCT. The CT60 genotype influences relapse and aGVHD, probably due to its action on CTLA-4 alternative splicing.

Journal Article; BACKGROUND AND OBJECTIVES Cancer testis antigens (CTA) provide attractive targets for cancer-specific immunotherapy. Although CTA genes are expressed in some normal tissues, such as the testis, this immunologically protected site lacks MHC I expression and as such, does not present self antigens to T cells. To date, CTA genes have been shown to be expressed in a range of solid tumors via demethylation of their promoter CpG islands, but rarely in chronic myeloid leukemia (CML) or other hematologic malignancies. DESIGN AND METHODS In this study, the methylation status of the HAGE CTA gene promoter was analyzed by quantitative methylation-specific polymerase chain reaction (MSP) and sequencing in four Philadelphia-positive cell lines (TCC-S, K562, KU812 and KYO-1) and in CML samples taken from patients in chronic phase (CP n=215) or blast crisis (BC n=47). HAGE expression was assessed by quantitative reverse transcriptase-polymerase chain reaction. RESULTS The TCC-S cell line showed demethylation of HAGE that was associated with over-expression of this gene. HAGE hypomethylation was significantly more frequent in BC (46%) than in CP (22%) (p=0.01) and was correlated with high expression levels of HAGE transcripts (p

Effect of mismatching for mHA UTA2-1 on clinical outcome after HLA-identical sibling donor allo-SCT

Granulocyte colony-stimulating factor (G-CSF)-mobilized peripheral blood (PB) is increasingly selected as a source of stem cells for allogeneic transplantation.1 The shift from using bone marrow (BM) to PB stem cells is based on the faster haematological recovery and lower transplant-related mortality (TRM) in patients with advanced disease observed after transplantation with PB.2 However, it remains unclear whether the use of PB is associated with an increased incidence of acute graft-versus-host disease (GvHD). Several retrospective and randomized prospective studies comparing BM and PB found a similar incidence of acute GvHD,2, 3 except the European Group for Blood and Marrow Transplantation (EBMT) study, which seems to indicate that PB transplants are associated with an increased cumulative incidence of acute GvHD.4 This association was recently confirmed by a meta-analysis of nine randomized trials.5 Nevertheless, it seems clear that PB transplants have an increased risk of chronic GvHD.2, 3, 4, 5

We have analyzed the regulation and expression of ASPP members, genes implicated in the regulation of the apoptotic function of the TP53 tumor-suppressor gene, in acute lymphoblastic leukemia (ALL). Expression of ASPP1 was significantly reduced in ALL and was dependent on hypermethylation of the ASPP1 gene promoter. Abnormal ASPP1 expression was associated with normal function of the tumor-suppressor gene TP53 in ALL. The analyses of 180 patients with ALL at diagnosis showed that the ASPP1 promoter was hypermethylated in 25% of cases with decreased mRNA expression. Methylation was significantly higher in adult ALL vs childhood ALL (32 vs 17%, P¼0.03) and T-ALL vs B-ALL (50 vs 9%, P¼0.001). Relapse rate (62 vs 44%, P¼0.05) and mortality (59 vs 43%, P¼0.05) were significantly higher in patients with methylated ASPP1. DFS and OS were 32.8 and 33.7% for patients with unmethylated ASPP1 and 6.1 and 9.9% for methylated patients (Po0.001 y Po0.02, respectively). On the multivariate analysis, methylation of the ASPP1 gene promoter was an independent poor prognosis factor in ALL patients. Our results demonstrate that decreased expression of ASPP1 in patients with ALL is due to an abnormal methylation o

The PARK2 gene, previously identified as a mutated target in patients with autosomal recessive juvenile parkinsonism (ARJP), has recently been found to be a candidate tumor suppressor gene in ovarian, breast, lung and hepatocellular carcinoma that maps to the third common fragile site (CFS) FRA6E. PARK2 is linked to a novel described PACRG gene by a bidirectional promoter containing a defined CpG island in its common promoter region. We have studied the role of promoter hypermethylation in the regulation of PARK2 and PACRG expression in different tumor cell lines and primary patient samples. Abnormal methylation of the common promoter of PARK2 and PACRG was observed in 26% of patients with acute lymphoblastic leukemia and 20% of patients with chronic myelogenous leukemia (CML) in lymphoid blast crisis, but not in ovarian, breast, lung, neuroblastoma, astrocytoma or colon cancer cells. Abnormal methylation resulted in downregulation of PARK2 and PACRG gene expression, while demethylation of ALL cells resulted in demethylation of the promoter and upregulation of PARK2 and PACRG expression. By FISH, we demonstrated that a lack of PARK2 and PACRG expression was due to biallelic hypermethylation and not to deletion of either PARK2 or PACRG in ALL. In conclusion, our results demonstrate for the first time that the candidate tumor suppressor genes PARK2 and PACRG are epigenetically regulated in human leukemia, suggesting that abnormal methylation and regulation of PARK2 and PACRG may play a role in the pathogenesis and development of this hematological neoplasm.

In this study, we report the case of a Philadelphia (Ph) positive chronic myelogenous leukemia (CML) patient with the presence of p190 and p210 BCR-ABL1 mRNA fusion transcripts derived from e1a2 and b3a2 BCR-ABL1 genomic rearrangements, respectively. The presence of e1a2 BCR-ABL1 genomic rearrangement was seen in 2 different clones, one with the rearrangement and another one with the rearrangement and deletion of the BCR gene of the non-rearranged chromosome 22. After treatment with imatinib, the p210 transcript could not be detected, whereas p190 was still present 6 months after initiation of imatinib therapy and progression to blast phase. The absence of p210 transcript post treatment indicates that the clone with b3a2 responded to imatinib and that the observed resistance was associated to cells harboring the e1a2 genomic rearrangement. Despite resistance of this patient to imatinib, no evidence of mutations in the kinase domain of ABL1 was found. Loss of normal BCR in one cell clone may contribute to the resistance to imatinib due to the lack of BCR mediated inhibition of BCR-ABL1.

Increasing mixed chimerism (MC) after allogeneic stem cell transplantation (SCT) has been associated with a high risk of relapse in acute leukemia. We evaluated a new method for chimerism detection, based on the quantitative real-time PCR (qrt-PCR) amplification of null alleles or insertion/deletion polymorphisms (indels). All qrt-PCR assays with null alleles and indels attained a sensitivity of at least 10(-4), as well as good intra- and interassay concordance, and a high accuracy in experiments with cell mixtures. Informativeness was found in 80.3% of the 61 donor/recipient pairs tested. Nonrelapsed patients showed a progressive decrease in peripheral blood chimerism to values below 0.01% (complete chimerism (CC)). Bone marrow chimerism failed to reach CC more than 4 years after SCT. Increasing MC was observed prior to relapse in 88.2% of patients. Compared with conventional PCR amplification of variable number of tandem repeats, qrt-PCR predicted a significantly higher number of relapses (88.2 vs 44.4%) with a median anticipation period of 58 days. In conclusion, chimerism determination by qrt-PCR amplification of null alleles and indels constitutes a useful tool for the follow-up of patients with acute leukemia after SCT, showing better results than those obtained with conventional PCR.

Promoter hypermethylation and global hypomethylation are independent epigenetic events in lymphoid leukemogenesis with opposing effects on clinical outcome