A scoring system to predict molecular responses in patients with chronic myeloid leukemia in the chronic phase receiving initial imatinib therapy / 中华血液学杂志

Objective: To develop a scoring system to predict molecular responses in patients with chronic myeloid leukemia in the chronic phase (CML-CP) receiving initial imatinib therapy. Methods: Data from consecutive adults with newly diagnosed CML-CP treated by initial imatinib was interrogated and subjects were distributed randomly into training and validation cohort, in a ratio of 2∶1. Fine-gray models were applied in the training cohort to identify co-variates of predictive value for major molecular response (MMR) and MR4. A predictive system was built using significant co-variates. The predictive system was then tested in the validation cohort and the area under the receiver-operator characteristic curve (AUROC) was used to estimate accuracy of the predictive system. Results: 1 364 CML-CP subjects receiving initial imatinib were included in this study. Subjects were distributed randomly into training cohort (n=909) and validation cohort (n=455) . In the training cohort, the male gender, European Treatment and Outcome Study for CML (EUTOS) Long-Term Survival (ELTS) intermediate-risk, ELTS high-risk, high WBC (≥130×10(9)/L or 120×10(9)/L, MMR or MR4) and low HGB (<110 g/L) at diagnosis were significantly related with poor molecular responses and were given points based on their regression coefficients. For MMR, male gender, ELTS intermediate-risk and low HGB (<110 g/L) were given 1 point; ELTS high-risk and high WBC (≥130×10(9)/L) , 2 points. For MR4, male gender was given 1 point; ELTS intermediate-risk and low HGB (<110 g/L) were given 2 points; high WBC (≥120×10(9)/L) , 3 points; ELTS high-risk, 4 points. We divided all subjects into 3 risk subgroups according to the predictive system above. Cumulative incidence of achieving MMR and MR4 in 3 risk subgroups was significantly different in both training and validation cohort (all P values <0.001) . In the training and validation cohorts, the time-dependent AUROC ranges of MMR and MR4 predictive systems were 0.70-0.84 and 0.64-0.81, respectively. Conclusions: A scoring system combining gender, WBC, HGB level and ELTS risk was built to predict MMR and MR4 in CML-CP patients receiving initial imatinib therapy. This system had good discrimination and accuracy, which could help phsicians optimize the selsction of initial TKI-therapy.

Therapeutic Drug Monitoring of Imatinib in Patients of Chronic Myeloid Leukemia - Chronic Phase

Introduction: Tyrosine kinase inhibitor is recommended for the initial management of chronic phase chronic myeloid leukemia (CP CML) based on the more favorable balance of toxicity and long-term disease control. Background: Mean trough plasma Imatinib Mesylate (IM) levels are detected to be significantly higher in patients with a complete cytogenetic response or major molecular response (MMR). Methodology: The primary objective of the study was to correlate the IM drug levels with MMR on two different occasions at least 3 months apart and to study the variation in the plasma trough levels of IM during the treatment with standard dose for at least 12 months. Results: After exclusion, 30 patients of CML-CP in MMR, on standard dose over a period of 2 years were finally analyzed. The mean IM plasma levels (IPLs) of the first sample for all patients were 1722 ± 566 ng/ml (IPL-1) with a corresponding mean molecular response (MR) 0.0257 ± 0.0279 breakpoint cluster region-abelson murine leukemia (BCR-ABL) IS % (MR-1). The mean IPLs of the second sample for all patients were 1549 ± 375 ng/ml (IPL-2) with a corresponding mean MR 0.0143 ± 0.0184 BCR-ABL IS % (MR-2). Area under the receiver operating characteristic curve for IPL-1 was 0.565 and IPL-2 was 0.639. For IM level at second point of 1800 ng/ml, the specificity for predicting MMR was 81.8% and sensitivity was 31.6%. Conclusion: Monitoring of trough IM plasma concentrations may become the part of standard management of CML patients.

Distribution of common BCR-ABL fusion transcripts and their impact on treatment response in Imatinib treated CML patients: A study from India

Background: Philadelphia chromosome (Ph): Hallmark of CML is caused by reciprocal translocation between chromosomes 9 and 22 resulting in BCR-ABL fusion protein. Most commonly associated breakpoint with CML is M-bcr in exon 13 or exon 14, producing splice variant b2a2 or b3a2 respectively. The distribution of these transcripts and their influence on clinico-hematological parameters is variable. Impact of the fusion transcripts on treatment outcome in Imatinib treated CML patients is still a matter of debate. Aims/settings and design: We conducted this study on 400 CML-CP patients to look for the distribution of fusion transcripts i.e. b3a2 and b2a2, their clinico-hematological profile and impact on treatment response in patients treated with Imatinib. Material and Methods: CML-CP was diagnosed by reverse transcriptase PCR (RT-PCR) for the BCR-ABL fusion transcript. Real-time quantitative PCR (RQ-PCR) was performed on peripheral blood every 3-6 monthly to look for treatment response. Results: The overall frequency of b3a2 transcript was observed in 288 (72%) followed by b2a2 in 104 (26%) and hybrid fusion transcript (b3a2 + b2a2) was seen in 8 (2%) cases. MMR was attained in 198/288 (68.7%) patients with b3a2 transcript and 90/288 (31.3%) patients failed to achieve MMR after 12 months of Imatinib therapy. Among the patients with b2a2 transcript, 44/104 (42.3%) patients achieved MMR and 60/104 (57.7%) patients failed to achieve MMR after 12 months of Imatinib therapy. Conclusions: In conclusion, the frequency of b3a2 transcript was more as compared to b2a2 transcript. MMR was significantly higher in patients with b3a2 transcript as compared to patients with b2a2.

Situación actual de la leucemia mieloide crónica en Costa Rica / (Current situation of chronic myeloid leukemia in Costa Rica)

Resumen Justificación y objetivo: la leucemia mieloide crónica constituye un paradigma de reversión de neoplasia con un tratamiento específico basado en los inhibidores de tirosina quinasa. Aunque la situación epidemiológica ha sido estudiada en países primermundistas, los estudios en Latinoamérica son escasos. Con el fin de actualizar la situación real de la LMC en la región centroamericana, el estudio pretende describir la epidemiología de la leucemia mieloide crónica en Costa Rica. Métodos: se evaluaron 133 pacientes con la enfermedad, mediante monitoreo hematológico y molecular. Se analizó la respuesta de estos casos a tratamiento conforme a las siguientes variables: respuesta hematológica, respuesta molecular y supervivencia global, libre de evento, progresión, así como la prevalencia de mutaciones que confieren resistencia al tratamiento. Resultados: la respuesta hematológica completa fue del 97,7%, y la molecular mayor, a los 12 meses, fue del 43,4%. El seguimiento recomendado por la guía European LeukemiaNet se alcanzó solo en un 68,4% de los pacientes en el primer año, bajando al 57,7%, posteriormente. Un total de 92 pacientes alcanzó respuesta molecular mayor en algún momento; de ellos, el 87,0% conservó respuesta. La supervivencia libre de evento a 3 años fue del 65,7%, libre de progresión del 92,2% y global del 89,2%. La mutación más frecuente encontrada en el gen ABL fue la T315I. Conclusión: el tratamiento de la leucemia mieloide crónica en Costa Rica presenta una eficacia comparable a lo reportado en otros países, con una respuesta molecular mayor inferior a lo esperado, debido a dificultades de acceso al medicamento y monitoreo de la enfermedad.

Abstract Background and aim: Chronic myeloid leukemia is a paradigm of reversion of neoplasia with a specific treatment based on tyrosine kinase inhibitors. Although the epidemiological situation has been studied in first world countries, studies in Latin American countries are scarce. In order to update the real situation of the chronic myeloid leukemia in our Central American region, this study aims to describe the epidemiology of chronic myeloid leukemia in Costa Rica. Methods: 133 patients with the disease were evaluated through hematological and molecular monitoring. The response of these cases to treatment was analyzed by the following variables: haematological response, molecular response and overall survival, event-free, progression, as well as the prevalence of mutations that confer resistance to treatment. Results: The complete haematological response was 97.7% and the molecular response greater than 12 months was 43.4%. The follow-up recommended by the European LeukemiaNet guideline was reached in only 68.4% of the patients in the first year, decreasing to 57.7% later on. A total of 92 patients achieved a higher molecular response at some point, of which 87.0% retained a response. The 3-year event-free survival was 65.7%, progression free of 92.2% and overall of 89.2%. The most frequent mutation found in the ABL gene was T315I. Conclusion: The treatment of chronic myeloid leukemia in Costa Rica presents an efficacy comparable to that reported in other countries, with a lower molecular response than expected due to difficulties in accessing medication and monitoring the disease.

Molecular response to imatinib mesylate of Brazilian patients with chronic myeloid leukemia

Abstract Background Imatinib mesylate has revolutionized the treatment of chronic myeloid leukemia leading to significant reductions of BCR-ABL1 transcript levels in peripheral blood. Objective To evaluate the response to imatinib mesylate treatment (400 mg/day) in Brazilian patients in the chronic phase of chronic myeloid leukemia monitored by quantitative real time polymerase chain reaction. Methods Between October 2002 and October 2010, 3169 peripheral blood samples were collected from 1403 patients from 3 to 5 months, 6 to 11 months, 12 to 17 months, 18 to 23 months and ≥24 months after beginning imatinib treatment. Eighty-two patients had samples available and analyzed for all time intervals. BCR-ABL1 quantification was performed by quantitative real time polymerase chain reaction using the ABL1 gene as the control. Results of the BCR-ABL1 ratio as a percentage were reported by the international scale (IS) using the laboratory conversion factor (0.51). Results In the first interval, 80.8% of patients achieved the optimal response (BCR-ABL1 IS ≤ 10%). In the second period, 69.1% achieved optimal response (BCR-ABL1 IS ≤ 1%) and, between 12 and 17 months, 47.3% achieved major molecular response (BCR-ABL1 IS ≤ 0.1%). Conclusions The results of this retrospective study show that the response to imatinib treatment (400 mg/day) of Brazilian patients in the chronic phase of chronic myeloid leukemia is within the expected profile when compared to patients reported in international prospective randomized studies.

The predictive value of early molecular response in chronic myeloid leukaemia patients treated with imatinib in a single real-world medical centre in a developing country

<p><b>INTRODUCTION</b>The prognosis of patients with chronic myeloid leukaemia (CML) has improved since the introduction of imatinib. However, patients who do not achieve complete cytogenetic response (CCyR) and major molecular response (MMR) have poorer prognosis. Recent clinical trials have demonstrated that early and deeper cytogenetic and molecular responses predict a better long-term outcome. This study aimed to analyse the relationship between early molecular response and clinical outcome in a real-life setting.</p><p><b>METHODS</b>This retrospective study included all patients with CML, in chronic or accelerated phase, who were treated with imatinib at University of Malaya Medical Centre, Malaysia.</p><p><b>RESULTS</b>A total of 70 patients were analysed. The median follow-up duration was 74 months, and the cumulative percentages of patients with CCyR and MMR were 80.0% and 65.7%, respectively. Overall survival (OS) and event-free survival (EFS) at ten years were 94.3% and 92.9%, respectively. Patients who achieved CCyR and MMR had significantly better OS and EFS than those who did not. At six months, patients who had a BCR-ABL level ≤ 10% had significantly better OS and EFS than those who had a BCR-ABL level > 10%. The target milestone of CCyR at 12 months and MMR at 18 months showed no survival advantage in our patients.</p><p><b>CONCLUSION</b>Our data showed that imatinib is still useful as first-line therapy. However, vigilant monitoring of patients who have a BCR-ABL level > 10% at six months of treatment should be implemented so that prompt action can be taken to provide the best outcome for these patients.</p>

Molecular response to imatinib & its correlation with mRNA expression levels of imatinib influx & efflux transporters in patients with chronic myeloid leukaemia in chronic phase.

Background & objectives: Imatinib is the standard first-line treatment for chronic myeloid leukaemia (CML) patients. About 20 to 30 per cent patients develop resistance to imatinib and fail imatinib treatment. One of the mechanisms proposed is varying expression levels of the drug transporters. This study was aimed to determine the expression levels of imatinib transporter genes (OCT1, ABCB1, ABCG2) in CML patients and to correlate these levels with molecular response. Methods: Sixty three CML chronic phase patients who were on 400 mg/day imatinib for more than two years were considered for gene expression analysis study for OCT1, ABCB1 and ABCG2 genes. These were divided into responders and non-responders. The relative transcript expression levels of the three genes were compared between these two categories. The association between the expression values of these three genes was also determined. Results: No significant difference in the expression levels of OCT1, ABCB1 and ABCG2 was found between the two categories. The median transcript expression levels of OCT1, ABCB1 and ABCG2 genes in responders were 26.54, 10.78 and 0.64 versus 33.48, 7.09 and 0.53 in non-responders, respectively. A positive association was observed between the expression of the ABCB1 and ABCG2 transporter genes (r=0.407, P<0.05) while no association was observed between the expression of either of the ABC transporter genes with the OCT1 gene. Interpretation & conclusions: Our findings demonstrated that the mRNA expression levels of imatinib transporter genes were not correlated with molecular response in CML patients. further studies need to be done on a large sample of CML patients to confirm these findings.

In silico analysis of ESTs from roots of Rangpur lime (Citrus limonia Osbeck) under water stress

CitEST project resulted in the construction of cDNA libraries from different Citrus sp. tissues under various physiological conditions. Among them, plantlets of Rangpur lime were exposed to hydroponic conditions with and without water stress using PEG6000. RNA from roots was obtained and generated a total of 4,130 valid cDNA reads, with 2,020 from the non-stressed condition and 2,110 from the stressed set. Bioinformatic analyses measured the frequency of each read in the libraries and yielded an in silico transcriptional profile for each condition. A total of 40 contigs were differentially expressed and allowed to detect up-regulated homologue sequences to well known genes involved in stress response, such as aquaporins, dehydrin, sucrose synthase, and proline-related synthase. Some sequences could not be classified by using FunCat and remained with an unknown function. A large number of sequences presented high similarities to annotated genes involved with cell energy, protein synthesis and cellular transport, suggesting that Rangpur lime may sustain active cell growth under stressed condition. The presence of membrane transporters and cell signaling components could be an indication of a coordinated morphological adaptation and biochemical response during drought, helping to explain the higher tolerance of this rootstock to water stress.

Accelerated Phase Chronic Myeloid Leukemia in Complete Molecular Response with STI571 / 대한혈액학회지

STI571 is an effective agent for the patients with chronic myeloid leukemia (CML). But, complete molecular response with STI571 is rarely reported in accelerated phase CML. Here we report a patient with accelerated phase CML who achieved complete molecular response with STI571. A 60-year old female patient visited emergency room with syncope. Her white blood cell count was 30,800/microliter (basophil 23%), hemoglobin 8.9g/dL, and platelet counts 2,748,000/microliter. Bone marrow was hypercellular with increase in megakaryocyte and basophils (15%). She was diagnosed as an accelerated phase CML. Seven days after stopping hydroxyurea, we used STI571 in a daily oral dose of 600mg. Generalized edema and skin rash were observed 15 days after treatment (all grade 1) and were controlled well with conservative management. Complete hematologic and cytogenetic responses were achieved after 1 month and 3 months of therapy with STI571 respectively. Complete molecular response was simultaneously proven by conventional reverse transcriptase PCR and real-time PCR analysis. The patient still remained in complete hematologic, cytogenetic, and molecular responses for 24 months. Treatment with STI571 was well tolerated and rapid hematologic improvement was observed. This case shows STI571 can induce complete molecular response as well as cytogenetic response in accelerated phase CML.