BackgroundThrough high-throughput next-generation sequencing of promoters of solute carrier and ATP-binding cassette genes, which encode drug transporters, we aimed to identify SNPs associated with the response to imatinib administered for first-line treatment of patients with chronic myeloid leukemia.Methods In silico analysis using publicly available databases was done to select the SLC and ABC genes and their promoters for the next-generation sequencing. SNPs associated with the imatinib response were identified using Fisher’s exact probability tests and subjected to the linkage disequilibrium analyses with regulatory loci of concerned genes. We analyzed cumulative achievement of major molecular response and probability of event free survival in relation to identified SNP genotypes in 129 CML patients and performed multivariate analysis for determination of genotypes as independent predictors of outcome. Gene expression analysis of eight cell lines naturally carrying different genotypes was performed to outline an impact of genotypes on the gene expression.ResultsWe observed significant differences in the frequencies of the rs460089-GC and rs460089-GG (SLC22A4) genotypes among rs2631365-TC (SLC22A5) genotype carriers that were associated with optimal and non-optimal responses, respectively. Loci rs460089 and rs2631365 were in highly significant linkage disequilibrium with 12 regulatory loci in introns of SLC22A4 and SLC22A5 encoding imatinib transporters. Genotype association analysis with the response to imatinib indicated that rs460089-GC carriers had a significantly higher probability of achieving a stable major molecular response (BCR-ABL1 transcript level below or equal to 0.1% in the international scale). In contrast, the rs460089-GG represented a risk factor for imatinib failure, which was significantly higher in rs460089-GG_rs2631365-TC carriers.ConclusionsThis exploratory study depicted potentially important genetic markers predicting outcome of imatinib treatment, which may be helpful for tailoring therapy in clinical practice.Electronic supplementary materialThe online version of this article (doi:10.1186/s13046-017-0523-3) contains supplementary material, which is available to authorized users.

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Tyrosine kinase inhibitors (TKI) have completely changed the prognosis of patients with Ph+ chronic myeloid leukemia (CML). The occurrence of a second malignancy (SM) in CML patients successfully treated with TKI may significantly affect their prognosis. In a retrospective study of 1,038 patients with CML treated at 10 centers in the Czech Republic and Slovakia between 2000 and 2009, SM was detected in 35 (3.37%) patients after TKI therapy was initiated. The median intervals from the diagnosis of CML and from the start of TKI therapy to the diagnosis of SM were 58 months (range 2 - 214) and 32 months (range 1 - 102), respectively. The observed age-standardized incidence of SM after the start of TKI therapy was 8.95 / 1,000 person-years. Comparison of the incidence of SM in CML patients with population data was performed only for patients from the Czech Republic. The age-standardized incidence rate of all malignant tumors except non-melanoma skin cancers was 6.76 (95% CI: 6.74; 6.78) / 1,000 person-years in 2000 - 2007 while the incidence rate of SM in 708 CML patients from the Czech Republic treated with TKI was 9.84 (95% CI: 6.20; 13.48) / 1,000 person-years, i.e. 1.5-fold higher, although the difference was statistically insignificant. The distribution of SM types in CML patients treated with TKI was similar to that in the age-standardized general Czech population. The median overall survival (OS) of patients treated with TKI who also developed SM (57 months) was shorter than the OS of patients treated with TKI but not suffering from SM (median OS not reached, log rank test p < 0.001. Prospective long-term population-based studies in CML patients treated with TKI as first-line therapy are needed to determine the relationship of SM to KTI therapy.

IntroductionImatinib mesylate is the drug of choice for patients with chronic myeloid leukemia (CML). Imatinib pharmacokinetics is affected by a number of transport proteins and enzymes.Material and methodsIn the present study we evaluated the association of eight polymorphisms in the seven genes CYP3A5*3 (rs776746), CYP3A4*1 (rs2740574), CYP2C9*3 (rs1057910), SLC22A1 (rs683369), ABCB1 (rs1045642, rs1128503), ABCG2 (rs2231142) and ABCC2 (rs717620) with imatinib plasma level and achieving an optimal clinical response in 112 CML patients (53 men and 59 women).ResultsNo association was found between the examined polymorphisms in rs776746, rs2740574, rs1057910, rs683369, rs1045642, rs1128503, rs2231142, rs717620 and the achieved imatinib plasma level. The influence of rs776746 (CYP3A5*3) on the achievement of a complete cytogenetic response (CCyR) at 6 months was borderline non-significant (p = 0.06). Furthermore, no association was demonstrated between rs776746 polymorphisms and the achievement of a major molecular response (MMR) at 12 or 18 months. Polymorphisms rs776746, rs2740574, rs1057910, rs683369, rs1045642, rs1128503, rs2231142, rs717620 showed no impact on the optimal therapeutic response.ConclusionsDespite the results of some other studies, no other polymorphism we analyzed was associated with imatinib plasma level or clinical response. The treatment outcomes cannot be predicted using the candidate gene approach and treatment decisions cannot be made according to the polymorphisms investigated in this study.

Background:Patients (pts) with lower risk myelodysplastic syndromes (LR-MDS) and anemia experience severe fatigue that negatively impacts overall functioning and daily life. Fatigue can also be commonly reported with treatments for LR-MDS, the goals of which are to minimize transfusions and improve pt-reported outcomes (PRO). In the IMerge Phase 3 (Ph3) study (NCT02598661), imetelstat, a first-in-class telomerase inhibitor, demonstrated statistically significant and meaningfully improved 8-and 24-wk transfusion independence (TI) rates, durable TI, and increased hemoglobin levels compared with placebo in heavily red blood cell (RBC) transfusion-dependent (TD) non-del(5q) LR-MDS pts who were ineligible/relapsed/refractory to ESA and naive to lenalidomide/hypomethylating agents. We also evaluated pt reported fatigue (rate of deterioration/improvement) during treatment with imetelstat or placebo.