Relationship between molecular response and quality of life with bosutinib or imatinib for chronic myeloid leukemia.

Patients with newly diagnosed chronic phase chronic myeloid leukemia (CP CML) can be effectively treated with tyrosine kinase inhibitors (TKIs) and achieve a lifespan similar to the general population. The success of TKIs, however, requires long-term and sometimes lifelong treatment; thus, patient-assessed health-related quality of life (HRQoL) has become an increasingly important parameter for treatment selection. Bosutinib is a TKI approved for CP CML in newly diagnosed adults and in those resistant or intolerant to prior therapy. In the Bosutinib Trial in First-Line Chronic Myelogenous Leukemia Treatment (BFORE), bosutinib demonstrated a significantly higher major molecular response rate compared with imatinib, with maintenance of HRQoL (measured by the Functional Assessment of Cancer Therapy-Leukemia (FACT-Leu) questionnaire), after 12 months of first-line treatment. We examined relationships between molecular response (MR) and HRQoL. MR values were represented by a log-reduction scale (MRLR; a continuous variable). A repeated-measures longitudinal model was used to estimate the relationships between MRLR as a predictor and each FACT-Leu domain as an outcome. Effect sizes were calculated to determine strength of effects and allow comparisons across domains. The majority of FACT-Leu domains (with the exception of social well-being and physical well-being) demonstrated a significant relationship with MRLR (p < 0.05). Our results showed variable impact of clinical improvement on different dimensions of HRQoL. For patients who achieved MR5, emotional well-being and leukemia-specific domains showed the greatest improvement, with medium differences in effect sizes, whereas social well-being and physical well-being had the weakest relationship with MR.

BCR-ABL1 transcript types showed distinct laboratory characteristics in patients with chronic myeloid leukemia.

In chronic myeloid leukemia (CML) two main types of messenger RNA (e14a2 and e13a2) can be produced by BCR-ABL1 gene rearrangement. Due to conflicting results, the clinical value of these transcripts remains controversial. The aim of this study was to identify associations of e14a2 and e13a2 transcripts with laboratory variables and also the response to treatment. This study included 203 adult patients with CML treated with Imatinib as first-line drug in a reference hematology center in Northeast Brazil. Clinical and laboratory data were obtained after informed consent. Samples were collected for RNA extraction and analyzed by reverse transcription-polymerase chain reaction (PCR), according to the international protocol BIOMED-1. The LeukemiaNet 2013 criteria were used to establish the molecular response. The frequency distribution of the BCR-ABL1 transcripts was e14a2 (64%), e13a2 (34%), and double positives (2%). The results showed a statistically significant association of the e14a2 transcript type with thrombocytosis (P = 0.0005) and the e13a2 with higher leukocyte count (P = 0.0491). In a subgroup of 44 patients, the molecular response to treatment with Imatinib was assessed by quantitative PCR at 3 months (BCR-ABL1 ≤ 10%), 6 months (BCR-ABL1 ≤ 1%), or 12 months (BCR-ABL1 ≤ 0.1%). Although patients with the transcript e14a2 showed higher frequency of good responses than patients with the transcript e13a2, this difference was not statistically significant. In agreement with published data, our results showed association of the BCR-ABL1 transcript e14a2 with thrombocytosis and the BCR-ABL1 transcript e13a2 with higher leukocytosis in patients with chronic myeloid leukemia.

Medical Devices; Immunology and Microbiology Devices; Classification of the BCR­ABL Quantitation Test. Final order.

The Food and Drug Administration (FDA or we) is classifying the BCR-ABL quantitation test into class II (special controls). The special controls that apply to the device type are identified in this order and will be part of the codified language for the BCR-ABL quantitation test's classification. We are taking this action because we have determined that classifying the device into class II (special controls) will provide a reasonable assurance of safety and effectiveness of the device. We believe this action will also enhance patients' access to beneficial innovative devices, in part by reducing regulatory burdens.

Nilotinib 300 mg twice daily: an academic single-arm study of newly diagnosed chronic phase chronic myeloid leukemia patients.

The introduction and the extended clinical use of nilotinib in the first-line treatment of chronic myeloid leukemia have been based on company-sponsored trials. Independent confirmations are extremely important. We report an investigator-sponsored study of nilotinib 300 mg twice daily in 130 chronic myeloid leukemia patients in early chronic phase. A deep molecular response was achieved in 46% (MR4.0) and 17% (MR4.5) of patients at 2 years; 58% of the enrolled patients achieved a MR4.0 at least once, with a sustained MR4.0 in 52% of them. With a median observation of 29 months (range 24-37 months), 77% of patients were still on treatment with nilotinib. The reasons for permanent discontinuation were: 3% progression, 5% failure or suboptimal response, 8% adverse events, 1% treatment-free remission, and 5% other reasons. Thirteen thrombotic arterial events were reported in 12 patients. A prospective evaluation of metabolic effects showed an increase of fasting glucose without significant variations of glycated hemoglobin, an increase of total cholesterol (both low density lipoprotein and high density lipoprotein fractions) and a decrease of triglycerides. This study confirms a high and rapid efficacy of nilotinib 300 mg twice daily and provides detailed information on the type and incidence of non-hematologic and metabolic adverse events (clinicaltrials.gov identifier: 01535391).

Younger patients with chronic myeloid leukemia do well in spite of poor prognostic indicators: results from the randomized CML study IV.

Since the advent of tyrosine kinase inhibitors, the impact of age on outcome of chronic myeloid leukemia (CML) patients has changed. We therefore analyzed patients from the randomized CML study IV to investigate disease manifestations and outcome in different age groups. One thousand five hundred twenty-four patients with BCR-ABL-positive chronic phase CML were divided into four age groups: (1) 16-29 years, n = 120; (2) 30-44 years, n = 383; (3) 45-59 years, n = 495; and (4) ≥60 years, n = 526. Group 1 (adolescents and young adults (AYAs)) presented with more aggressive disease features (larger spleen size, more frequent symptoms of organomegaly, higher white blood count, higher percentage of peripheral blasts and lower hemoglobin levels) than the other age groups. In addition, a higher rate of patients with BCR-ABL transcript levels >10 % on the international scale (IS) at 3 months was observed. After a median observation time of 67.5 months, no inferior survival and no differences in cytogenetic and molecular remissions or progression rates were observed. We conclude that AYAs show more aggressive features and poor prognostic indicators possibly indicating differences in disease biology. This, however, does not affect outcome.

Phase 2 study of subcutaneous omacetaxine mepesuccinate for chronic-phase chronic myeloid leukemia patients resistant to or intolerant of tyrosine kinase inhibitors.

Omacetaxine mepesuccinate (omacetaxine) is a first-in-class cephalotaxine with a unique mode of action, independent of BCR-ABL, that has shown promising activity in patients with chronic myeloid leukemia (CML). This multicenter, noncomparative, open-label phase 2 study evaluated the efficacy and safety of subcutaneous omacetaxine in CML patients with resistance or intolerance to two or more tyrosine kinase inhibitors (TKIs); results in patients in chronic phase are reported here. Patients received subcutaneous omacetaxine 1.25 mg/m² twice daily days 1-14 every 28 days until hematologic response (up to a maximum of six cycles), then days 1-7 every 28 days as maintenance. Primary endpoints were rates of hematologic response lasting >8 weeks and major cytogenetic response (MCyR). Forty-six patients were enrolled: all had received imatinib, 83% had received dasatinib, and 57% nilotinib. A median 4.5 cycles of omacetaxine were administered (range, 1-36). Hematologic response was achieved or maintained in 31 patients (67%); median response duration was 7.0 months. Ten patients (22%) achieved MCyR, including 2 (4%) complete cytogenetic responses. Median progression-free survival was 7.0 months [95% confidence interval (CI), 5.9-8.9 months], and overall survival was 30.1 months (95% CI, 20.3 months-not reached). Grade 3/4 hematologic toxicity included thrombocytopenia (54%), neutropenia (48%), and anemia (33%). Nonhematologic adverse events were predominantly grade 1/2 and included diarrhea (44%), nausea (30%), fatigue (24%), pyrexia (20%), headache (20%), and asthenia (20%). Subcutaneous omacetaxine may offer clinical benefit to patients with chronic-phase CML with resistance or intolerance to multiple TKI therapies.

Significance of deeper molecular responses in patients with chronic myeloid leukemia in early chronic phase treated with tyrosine kinase inhibitors.

Most patients with chronic myeloid leukemia (CML) in chronic phase (CP) treated with tyrosine kinase inhibitors (TKI) achieve complete cytogenetic response (CCyR). An increasing number of patients also achieve deep molecular responses (MR). We determined the frequency and significance of deep MR after TKI therapy for CML in CP. MR included: major molecular response (MMR), MR4, MR4.5, and undetectable transcripts (UND), i.e., BCR-ABL/ABL of ≤0.1, ≤0.01, ≤0.0032%, and undetectable transcripts, respectively. Four hundred eighty-three patients received imatinib 400 mg/day (IM400, 71, July 2000 to April 2001), imatinib 800 mg/day (IM800, 204, June 2001 to July 2005), nilotinib (106, July 2005 to date), or dasatinib (102, November 2005 to date). UND rates at 36 months were 18.1, 30.6, 29.2, and 28.6%, respectively. Patients achieving UND have superior transformation-free survival (TFS) and overall survival (OS) versus those obtaining ≤MMR, but not other MR levels. At the 18- and 24-month landmark analysis, patients achieving UND have no advantage in TFS and OS compared to those achieving a lesser degree of MR. Among patients achieving MR4.5, those who maintain it for ≥2 years (susMR4·5) have no additional benefit in TFS or OS. Most patients with early CP CML receiving TKI achieve MMR. BCR-ABL transcripts become undetectable in a significant fraction of them. Deeper MR at 18 or 24 months are not associated with a benefit in TFS or OS. Furthermore, achieving susMR4·5 does not appear to further reduce the risk of transformation or death.

Profile of BCR-ABL transcript levels based on Sokal prognostic score in chronic myeloid leukemia patients treated with imatinib.

AIM: to elucidate the pattern of molecular response assessed by logarithmic reduction in BCR-ABL transcription levels based on Sokal prognostic score in chronic phase chronic myeloid leukemia (CML) patients receiving Imatinib treatment. METHODS: cross-sectional study was conducted in the Hematologic Outpatient Clinic, Dr. Soetomo Hospital Surabaya in all chronic phase CML patients from June 2008 to June 2012. Data on subject characteristics (age and sex), complete blood count with differential and spleen size were collected. Patients were stratified according to Sokal score at diagnosis. Real-time quantitative PCR (RT-qPCR) were used to monitor BCR-ABL levels in patients who fulfilled study. Proportion difference of complete molecular response (MR) was analyzed by chi-square test, while differences of BCR-ABL transcript level among Sokal prognostic scole subgroups was analyzed by Kruskal-Wallis test. RESULTS: 40 subjects finished the study. After 18 months of Imatinib treatment, the undetected BCR-ABL transcript level (complete MR) were 7(70%), 8(66.7%), and 9(50%) in low-, intermediate-, and high risk group patients, respectively (p=0.417). Although proportion of subjects with complete MR is higher in sokal low risk group compared to in sokal high risk groups (70% v.s. 50%), but this difference is not statistically significant (p=0.557). Kruskal-Wallis test showed that there was no significant difference of BCR-ABL transcript level among Sokal prognostic score subgroup (p=0.734). CONCLUSION: there was no difference of BCR-ABL transcript level among sokal prognostic score risk groups in chronic phase CML patients treated with Imatinib.

Plasma exposure of imatinib and its correlation with clinical response in the Tyrosine Kinase Inhibitor Optimization and Selectivity Trial.

BACKGROUND: This study evaluates the correlation between imatinib trough plasma concentrations (C(min)) and clinical response and safety in patients with newly diagnosed Philadelphia chromosome-positive chronic myeloid leukemia in chronic phase in the Tyrosine Kinase Inhibitor OPtimization and Selectivity (TOPS) trial. DESIGN AND METHODS: Patients were randomized 1:2 to 400 mg/day or 800 mg/day imatinib. Imatinib C(min) levels were collected at pre-dose before treatment, and at the end of months 1 (day 29), 6, 9, and 12. RESULTS: Imatinib C(min) were stable over time in the 400 mg/day dose arm, but showed a slight decrease in the 800 mg/day arm due to dose adjustments between months 1-6. The overall median imatinib C(min) levels were 1040, 1200, 1935, and 2690 ng/mL for the actual 300, 400, 600, and 800 mg/day doses, respectively. The rates of major molecular response (MMR) at 3, 6, 9, and 12 months, and complete cytogenetic response (CCyR) at 6 and 12 months were significantly lower among patients with the lowest imatinib C(min) levels at Day 29 (<1165 ng/mL, 25th percentile). There was an apparent association between high imatinib C(min) and the occurrence of grade 3/4 neutropenia and all-grade rash, diarrhea, arthralgia/myalgia, and all-cause edema. Conclusions Imatinib C(min) levels were relatively stable over time and proportional to the dose administered. Patients with an imatinib C(min) above 1165 ng/mL on Day 29 achieved MMR faster and had higher MMR and CCyR rates at 12 months. There appeared to be an association between imatinib C(min) and the frequency of some adverse events. This trial was registered at http://www.clinicaltrials.gov as NCT00124748.

Population pharmacokinetic and exposure-response analysis of nilotinib in patients with newly diagnosed Ph+ chronic myeloid leukemia in chronic phase.

PURPOSE: We investigated the population pharmacokinetics and exposure-response relationship of nilotinib in patients with newly diagnosed chronic myeloid leukemia (CML) in chronic phase. METHODS: Nilotinib was given at 300 mg or 400 mg twice daily. Serum concentration data (sparse and full pharmacokinetic profiles) were obtained from 542 patients over 12 months. A population pharmacokinetic analysis was performed using nonlinear mixed-effect modeling. Exposure-response relationships were explored graphically or using logistic regression models. RESULTS: Nilotinib concentrations were stable over 12 months. Patients in the 400 mg twice-daily arm had an 11.5% higher exposure than did those in the 300 mg twice-daily arm, and the relative bioavailability of nilotinib 400 mg twice daily was 0.84 times that of 300 mg twice daily. Patient demographics did not significantly affect nilotinib pharmacokinetics. The occurrence of all-grade total bilirubin elevation was significantly higher in patients with higher nilotinib exposure, and a positive correlation was also observed between nilotinib exposure and QTcF change on electrocardiograms from baseline. There was no significant relationship between nilotinib exposure and major molecular response at 12 months. CONCLUSIONS: There is a less than proportional dose-exposure relationship between nilotinib 300 mg and 400 mg twice-daily doses. Blood level testing is unlikely to play an important role in the general management of patients with newly diagnosed CML treated with nilotinib.

Delayed achievement of cytogenetic and molecular response is associated with increased risk of progression among patients with chronic myeloid leukemia in early chronic phase receiving high-dose or standard-dose imatinib therapy.

Patients not in complete cytogenetic response (CCyR) continuously face the competing possibilities of eventually achieving a cytogenetic response versus progressing. We analyzed the probability of achieving a CCyR, major molecular response, and progression in 258 patients with chronic myeloid leukemia in early chronic phase at 3, 6, and 12 months from imatinib start. The initial imatinib dose was 800 mg/day in 208 (81%) and 400 mg/day in 50 (19%) patients. For patients not in CCyR, the probability of achieving CCyR (P = .002) or major molecular response (P = .004) significantly decreased, whereas the risk of progression increased (P = .16) at each time point. Patients with a BCR-ABL1/ABL1 ratio greater than 1% to 10% after 3 months of imatinib had a 92% probability of achieving CCyR with continued therapy, similar to the 98% for those with 1% or less, but their risk of progression (11%) was almost 3-fold that of patients with a BCR-ABL1/ABL1 transcript ratio of 1% or less (4%) and similar to that of patients with transcript levels more than 10% (13%). These results suggest that patients not in CCyR after 12 months on imatinib have a higher risk of progression. This risk is discernible as early as 3 months into imatinib therapy by molecular analysis and may provide the rationale to institute therapies that render higher rates of early response.

A model of oscillatory blood cell counts in chronic myelogenous leukaemia.

In certain blood diseases, oscillations are found in blood cell counts. Particularly, such oscillations are sometimes found in chronic myelogenous leukaemia, and then occur in all the derived blood cell types: red blood cells, white blood cells, and platelets. It has been suggested that such oscillations arise because of an instability in the pluri-potential stem cell population, associated with its regulatory control system. In this paper, we consider how such oscillations can arise in a model of competition between normal (S) and genetically altered abnormal (A) stem cells, as the latter population grows at the expense of the former. We use an analytic model of long period oscillations to describe regions of oscillatory behaviour in the S-A phase plane, and give parametric criteria to describe when such oscillations will occur. We also describe a mechanism which can explain dynamically how the transformation from chronic phase to acute phase and blast crisis can occur.

Chronic myelogenous leukemia accompanied by megaloblastic anemia showing atypical clinical features.

Leukocytosis, splenomegaly, and an increased vitamin B(12) level are characteristic findings of chronic myelogenous leukemia in the chronic phase (CML-CP). Here, we report a patient with CML-CP accompanied by megaloblastic anemia. A 61-year-old man consulted our hospital because of anemia and thrombocytopenia. On physical examination, there were no remarkable findings; there was no hepatosplenomegaly. Laboratory findings were: hemoglobin 6.0 g/dl; MCV 113.6 fl; platelet count 100×10(9)/l; white cell count 8.66×10(9)/l; and LDH 1,236 IU/l. Peripheral blood smear demonstrated hypersegmented neutrophils and megalocytes with emergence of myeloblasts, giant metamyelocytes, and nucleated red cells. Vitamin B(12) and folic acid levels were low. Bone marrow examination showed megaloblastic change in the erythroblasts and myeloid hyperplasia. Following vitamin B(12) and folic acid administration, anemia and thrombocytopenia rapidly improved; thereafter, marked leukocytosis became evident. Based on the presence of t(9;22)(q34;q11) on cytogenetic study and a positive result for Major bcr/abl fusion gene, a diagnosis of CML-CP was established. This case illustrates that ineffective erythropoiesis results in anemia and thrombocytopenia in CML with vitamin B12 and/or folic acid deficiency.

Higher red blood cell distribution width at diagnose is a simple negative prognostic factor in chronic phase-chronic myeloid leukemia patients treated with tyrosine kinase inhibitors: A retrospective study.

ABSTRACT: The aim of this study was to evaluate the ability of the red blood cell distribution width (RDW) to predict prognosis and treatment response in chronic myeloid leukemia (CML)-chronic phase (CP) patients treated with tyrosine kinase inhibitor (TKIs).We retrospectively enrolled 93 newly diagnosed CML-CP patients treated with TKIs from 2009 to 2018 at the First Hospital of Lanzhou University. Patients were divided into 2 groups using an RDW of 18.65% determined by receiver operating characteristic curve analysis. We analyzed the correlation of treatment responses and the RDW compared to common scoring systems, as well as the correlation of the RDW with disease outcome, including overall survival (OS) and progression-free survival (PFS), and demographic and laboratory factors affecting outcome. Univariate analysis and Cox regression analysis were used.The median age of patients was 40 years, and 51 patients (54.8%) were men. A high RDW could predict treatment response at 3 months (P = .03) and 6 months (P = .02). The RDW was significantly lower in patients who achieved molecular response by 3 months (P < .001) and complete cytogenetic response by 6 months (P = .001) than in those who did not respond. Patients with a high RDW (>18.65%, n = 35) had significantly worse 5-year OS (77.1% vs 96.6%; P = .008) and PFS (80.0% vs 98.3%; P = .002) than those with a low RDW (≤18.65%, n = 58). Multivariate analysis demonstrated that a high RDW was an adverse predictor of OS (P = .005, HR (hazard ratio) = 9.741) and PFS (P = .009, HR = 16.735).The RDW is a readily available prognostic marker of outcome in patients with CML-CP and can predict treatment response to TKIs. Further larger and prospective studies are required.

Trough plasma concentration of imatinib reflects BCR-ABL kinase inhibitory activity and clinical response in chronic-phase chronic myeloid leukemia: a report from the BINGO study.

Pharmacokinetic (PK) factors have been suggested to be involved in the unfavorable clinical responses of chronic myeloid leukemia (CML) patients treated with imatinib. The purpose of this study was to clarify prognostic implications of PK factors in CML patients treated with imatinib. The plasma trough (C(min)) level of imatinib and serum α(1)-acid glycoprotein (AGP) level were measured on two different days in 65 CML patients treated with imatinib for more than 12 months. We further examined whether the C(min) level of imatinib actually reflects inhibitory activity against BCR-ABL kinase using the plasma inhibitory activity (PIA) assay. Since the differences of five patients were statistically rejected by the Smirnov-Grubbs' test, we excluded them for further analysis. The C(min) level was strongly associated with the achievement of MMR at the 12th month, and ROC analysis demonstrated C(min) levels and their discrimination potential for major molecular response (MMR) with the best sensitivity (63.2%) and specificity (68.2%) at a C(min) threshold of 974 ng/mL. The α(1)-Acid glycoprotein (AGP) level was within the normal range in 57 of 60 patients, indicating little impact of AGP on our study. There was a weak correlation between PIA against phospho (P)-BCR-ABL and the C(min) level of imatinib (r(2) = 0.2501, P = 0.0007), and patient plasma containing >974 ng/mL imatinib sufficiently inhibited P-BCR-ABL. These results collectively indicated that maintaining ∼1000 ng/mL of C(min) was clinically and biologically important for the optimal response in CML patients treated with imatinib. A prospective intervention study is required to establish PK-based management in CML patients treated with imatinib.

Cytogenetic and molecular responses in chronic phase chronic myeloid leukaemia patients receiving low dose of imatinib for intolerance to standard dose.

Imatinib mesylate is the gold standard treatment of chronic myeloid leukaemia (CML) and 400 mg/day is considered the standard dose. Although it is generally well tolerated, some patients require temporary drug discontinuation and permanent dose reduction because of haematological or non-haematological toxicities. Whether or not reduced doses are effective as the standard dose in inducing and/or maintaining complete cytogenetic and molecular response is not clear. We report the outcome of 45 CML patients in early (17) and late (28) chronic phase (CP) in whom, within a series of 250 patients treated with imatinib, reduced the dose of the drug after experiencing adverse events. Median time interval between the start of therapy and dose reduction was 58 days, whereas median administered dose was 300 mg/day. At 6 months from reduction, major cytogenetic responses (MCRs) were observed in 67% of patients, with 58% being complete cytogenetic remission (CCR), and complete molecular response (CMR) were obtained in 18% of patients. At 12 months, all patients who had obtained MCR reached CCR: this was significantly higher in low risk patients (87%) versus non-low risk patients (66 and 46%), and in early phase (82%) versus late phase (53.5%). CMR and major molecular response (MMR) were detected in 20 and 22% of patients, respectively. Low dose imatinib appears effective in patients with intolerance to standard dose, even though long-term effects remain to be established.

Plasma imatinib levels and ABCB1 polymorphism influences early molecular response and failure-free survival in newly diagnosed chronic phase CML patients.

Achieving early molecular response (EMR) has been shown to be associated with better event free survival in patients with chronic phase chronic myeloid leukemia (CP-CML) on Imatinib therapy. We prospectively evaluated the factors influencing the 2-year failure free survival (FFS) and EMR to imatinib therapy in these patients including day29 plasma Imatinib levels, genetic variants and the gene expression of target genes in imatinib transport and biotransformation. Patients with low and intermediate Sokal score had better 2-year FFS compared to those with high Sokal Score (p = 0.02). Patients carrying ABCB1-C1236T variants had high day29 plasma imatinib levels (P = 0.005), increased EMR at 3 months (P = 0.044) and a better 2 year FFS (P = 0.003) when compared to those with wild type genotype. This translates to patients with lower ABCB1 mRNA expression having a significantly higher intracellular imatinib levels (P = 0.029). Higher day29 plasma imatinib levels was found to be strongly associated with patients achieving EMR at 3 months (P = 0.022), MMR at 12 months (P = 0.041) which essentially resulted in better 2-year FFS (p = 0.05). Also, patients who achieved EMR at 3 months, 6 months and MMR at 12 months had better FFS when compared to those who did not. This study suggests the incorporation of these variables in to the imatinib dosing algorithm as predictive biomarkers of response to Imatinib therapy.

Quantitative detection of bcr-abl transcripts in chronic myeloid leukemia.

The optimal management of malignant haematological disorders depend on the degree of tumor load reduction after therapy. Chronic myeloid leukemia constitutes a clinical model for molecular detection and therapy surveillance of malignant disease since this entity was the first leukemia shown to be associated with a specific bcr-abl fusion gene in the patient's leukemia cells. Molecular monitoring of bcr-abl transcript levels by real-time quantitative PCR is increasingly used to assess treatment response in patients with chronic myeloid leukemia (CML). This has become particularly relevant in the era of imatinib therapy when residual levels of leukaemia usually fall below the level of detection by bone marrow cytogenetic analysis. We monitored bcr-abl transcript levels by quantitative real time PCR in 50 tunisian patients treated with imatinib for chronic myeloid leukemia in chronic phase for a median of 29 months (3-60) after they started imatinib.

Circulating microRNAs expression profile in newly diagnosed and imatinib treated chronic phase - chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is a stem cell derived malignant disorder result of translocation t(9;22)(q34;q11) called Philadelphia chromosome (Ph+). microRNAS (miRNAs) are involved in several biological processes, altering the progression of various pathologies, including CML. This study evaluated whether circulating miRNAs display differential expression profiles in peripheral blood of CML-Chronic Phase (CML-CP) patients newly diagnosed in comparison with CML-CP treated with imatinib. We obtained peripheral blood samples from CML-CP Ph+ patients divided among group 1 (untreated newly diagnosed) and group 2 (treated with imatinib). A pool of total leukocytes from healthy donors was considered as control group. Expression analyses were performed for 768 miRNAs by RT-qPCR array. Bioinformatic tools were used to identify significant pathways and interaction networks. We found 80 deregulated miRNAs between the groups and, according to bioinformatic analysis, they are involved in different pathways, including molecular mechanisms of cancer. The study allows better understanding of disease molecular behavior, and it is useful for possible monitoring CML treatment and prognostic biomarkers identification.