Egyptian Chronic Myeloid Leukemia Patients Research Articles

Utility of T315I mutation in Egyptian patients with chronic myeloid leukemia

ABSTRACT Chronic myeloid leukemia(CML) is a myeloproliferative neoplasm (MPN) characterized by the presence of the Philadelphia chromosome (BCR:ABL), and there is a higher risk in untreated CML to be transformed to blast crisis phase. The development of tyrosine kinase inhibitor (TKI) imatinib was a remarkable step in CML treatment. However, patients showed resistance due to some mutations including T315I which still be the most challenging mutation in CML. Therefore, the aim of our study is to screen T315I in our Egyptian CML patients to predict and determine the frequency of T315I in patients with TKIs resistance. AS-PCR performed on 50 CML patients resistant to the first-line TKIs and 50 CML patients respond to the first-line TKIs. Positive-T315I was found in 15 (30%) of TKIs resistant cases. T315I was significantly associated with higher WBC, platelet count, cellularity of BM aspiration and biopsy when compared to those with negative-T315I. Resistant positive-T315I was significantly associated with lower cumulative OS 55.9% and shorter mean OS 93.4 months when compared to resistant negative-T315I. We conclude that T315I can exist at the diagnosis before starting treatment. Therefore, screening test for T315I can be performed at the time of diagnosis to help in choosing the suitable treatment protocol.

Micro-RNA Biogenesis Genes (AGO1 and GEMIN4) Single Nucleotide Variants of Bad Prognosis and Poor Therapeutic Response in Egyptian Chronic Myeloid Leukemia Patients: Case–control Study

BACKGROUND: Chronic myeloid leukemia (CML) is one of the most common hematological tumors. Gene candidate studies cleared the association of single genetic variants (SNVs) to the risk and progression in CML. MicroRNA biogenesis genes disruption contributes a fundamental role in carcinogenesis. AIM: We aimed to determine the association between rs636832 and rs2740348 SNVs of AGO1 gene and GEMIN4 gene, respectively, and the risk and prognosis in CML Egyptian patients with 5 years survival estimation. METHODS: The study was conducted on 110 newly diagnosed CML patients and 110 age and sex healthy matched controls. Real-time polymerase chain reaction utilizing TaqMan probes was operated to demonstrate genetic modalities of rs636832 and rs2740348. RESULTS: No significance difference was observed between the cases and controls regarding the genotypic and allelic frequencies for both variants. On the other hand, the rs636832 GG genotype was more evident at a younger age of diagnosis and associated with the poor grades of the Sokal and Eutos scores. As well, rs2740348 CC genotype was encountered in high Eutos score levels. Regarding the response therapy, rs636832 GG genotype was overrepresented in the resistance to Imatinib while rs2740348 CC genotype was prevalent in the resistance to both Imatinib and Nilotinib. Overall survival was of no statistical significance for both variants. CONCLUSION: Our study revealed that the major homozygous genotypes of both variants were associated with bad prognostic clinical scores and poor response to therapy but with no role in CML risk.

Study and Survey of BCR-ABL Transcript Types in Chronic Myeloid Leukemia (CML) Young Egyptian Patients

Background: Geographic and ethnic variations contribute to the variability of incidences among CML registries. Reliable data concerning response rates to therapy in Arab nations is lacking. CML management areas are not in line with the current recommendations, due to sub-optimal timing of treatment decisions, under monitoring, and lack of molecular techniques or TKIs. Median age differs between cancer registries and clinical trials by 10-20 years. Objectives: Assessing the incidence of different BCR-ABL transcript types, among young Egyptian CML patients in different centers in Egypt to assess the impact of ethnic and demographic variables on disease outcome, particularly according to gender and age. And, the relationships of different transcript types with the disease characteristics and response to treatment type. Patients and Methods: This study was conducted on 93 patients with CML from databases of Ain Shams University CML clinic and Hematology and Bone Marrow units, databases of Laboratories testing BCR-ABL for diagnostic purposes & Other contributing medical centers, (51 males, 42 females) with age range (18 years to < 50 years) after obtaining a written informed consent. Results: Patients were divided into 3 groups according to BCR-ABL transcript type. 36 patients had b2-a2, 45 patients had b3-a2 and 12 patients had both. (38.7%, 48.4% and 12.9% respectively). Risk stratification according to Sokal score was done. 30 patients were of low risk, 60 patients were of intermediate risk and 3 patients were of high risk (32%, 65% and 3% respectively). Mean Sokal score in patients with b2-a2 was 0.79, in patients with b3-a2 was 0.88 and in patients with both was 0.83.Risk stratification according to Hasford score was done. 48 patients were of low risk, 45 patients were of intermediate risk and there were no high risk patients (52%, 48% and 0% respectively).Mean Hasford score in patients with b2-a2 was 652.9, in patients with b3-a2 was 831.9 and in patients with both was 914.4.All patients had low EUTOS risk score. Mean EUTOS score in patients with b2-a2 was 41.9, in patients with b3-a2 was 54.7 and in patients with both was 53.5. All patients presented with splenomegaly, the mean size of spleen was 18 cm at diagnosis. All patients presented with leukocytosis, mean basophilic count was (3×103/µL), mean eosinophilic count was (6.35×103/µL), mean platelet count was (364.4×103/µL).Patients’ BCR-ABL levels were measured by PCR at 5 time points: Initially, at 3 months, at 6 months, at 9 months and at 12 months. Patients with b2-a2 had higher PCR levels than the other 2 groups initially and at 3 months. The difference was statistically significant. Initially, PCR was higher in patients with b2-a2 compared to patients with b3-a2 and to patients with both (p=0.001 and p=0.011 respectively).At 3 months, PCR was higher in patients with b2-a2 compared to patients with b3-a2 (p=0.018).All other differences were not statistically significant. Conclusion: Patients with b2-a2 had higher PCR levels than the other 2 groups initially and at 3 months. There was no difference at 6 monthes & later.

Association of the Trough, Peak/Trough Ratio of Imatinib, Pyridine-N-Oxide Imatinib and ABCG2 SNPs 34 G>A and SLCO1B3 334 T>G With Imatinib Response in Egyptian Chronic Myeloid Leukemia Patients.

Imatinib mesylate (IM) is highly efficacious in the treatment of chronic myeloid leukemia (CML). Therapeutic drug monitoring and pharmacogenetic screening are affirmed for better management of IM therapy. The goal of this study was to gain a greater mechanistic understanding of the factors controlling variability in IM level and its relation to the response. One hundred and two patients with CML at chronic phase were recruited in this study. Blood samples were withdrawn at least 30 days after drug administration, and trough and peak concentrations of imatinib, N-des-methyl imatinib, and pyridine-N-oxide imatinib were determined by HPLC/MS/MS. Genetic polymorphism of the genes ABCG2 SNPs 34 G>A and 421C >A; ABCB1 SNPs 2677 G>A/T, 1236 C>T, 3435 C>T; SLCO1B3 SNPs 334 T>G and CYP3A5 were studied using PCR-RFLP technique. Our study presented significant higher trough IM (1,281 ± 578 ng/ml), lower Peak/Trough ratio, clearance (Cl), and elimination rate constant, ke, among patients who achieved favorable responses (N = 64) than those for patients who suffered unfavorable response (N = 37). The P/T ratio was the only significant independent factor affecting response, as the P/T ratio increased by one, the risk of unfavorable response increased by more than double as compared to favorable response with 95% CI (1.28–3.92, P = 00.005). Moreover, like the results of IM, the trough concentration of Pyridine-N-oxide imatinib was significantly higher (P = 0.01) and its P/T ratio was significantly lower (P = 0.008) in patients achieved favorable response than those without. The wild GG genotype of the ABCG2.34 G>A gene was associated with favorable response (P = 0.01), lower Cl, Ke and high plasma IM trough level than both (AA+GA) genotypes. ABCG2.421C >A (CC) genotype had a significantly higher plasma peak of IM, N-des-methyl imatinib and higher Css. The GG and TG alleles of the SLCO1B3.334 T>G gene were significantly correlated to favorable response, while the wild allele TT was linked to unfavorable response (P = 0.03). In conclusion, the trough and P/ T ratio for both IM and Pyridine-N-oxide imatinib, in addition to Polymorphism of ABCG2 SNPs 34 G>A and SLCO1B3.334 T>G gene, is a good predictor for response of IM in CML Egyptian patients.

Prognostic impact of Additional Chromosomal Abnormalities in Egyptian Chronic Myeloid Leukemia Patients

BACKGROUND: Emergence of additional chromosomal abnormalities (ACAs) in chronic myeloid leukemia (CML) is associated with disease progression to advanced phases and reflects the genetic instability of CML.&#x0D; AIM: Is to evaluate the frequency of ACAs in chronic phase (CP) and advanced disease (AP) CML patients and study their impact on patient’s outcome, overall survival (OS) and event-free survival (EFS).&#x0D; RESULTS: The studied group (n = 73) included 31 males (43%) and 42 females (57%). Median age of patients at diagnosis was 37 years (17–76). Median TLC was 208×109/L (2.1–784.2), median Hb was 9.4 g/dL (5.7–13), and median platelets count was 290.5×109/L (13–1271). We identified 32 patients (44%) with ACAs. ACAs emergence was significantly associated with advanced phases of CML (13/21, 62%) compared to CP (19/52, 36%) (p = 0.048). ACAs were associated with lower median OS and EFS in CP compared to AP (38 vs. 120 ms) and (58.3 vs. 77 ms) (p = 0.026 and p = 0.065, respectively). Early molecular responders (6/17, 35%) at 3 months, and 6 months (10/26, 38%) developed ACAs less than nonoptimal responders. Disease phase, hepatomegaly and bone marrow eosinophilia were significant predictors of OS (p &lt; 0.001, p = 0.02, p = 0.04, respectively).&#x0D; CONCLUSION: Early identification of ACAs in Ph+ metaphases at diagnosis and during therapy predicts CML outcome. ACAs emergence occurred at a higher frequency and at a younger age in our CML patients and are related to inferior EFS and OS.

MicroRNA 30a Mediated Autophagy and Imatinib Response in Egyptian Chronic Myeloid Leukemia Patients.

Imatinib Mesylate is the drug used for targeted tyrosine kinase inhibition in the beginning of management of all Chronic Myeloid Leukemia (CML) newly diagnosed cases. However, resistance presents a considerable limit to its efficacy. Currently, it is impossible to anticipate IM resistance which makes the recognition of early flags an important treatment goal in CML. In this work we studied the connection between microRNA 30a (miR-30a) and Beclin 1 mediated autophagy and IM resistance in Egyptian CML patients. The study included newly diagnosed (group I, n = 20), imatinib responder (group II, n = 30), imatinib resistant (group III, n = 30) CML patients and a healthy demographically matched control group (group IV, n = 20). miR-30a expression was assayed by quantitative reverse transcription polymerase chain reaction. The variation in expression of miR-30a between CML cases and healthy controls was calculated using relative quantification method (2-ΔΔCT). Beclin 1 was assayed in Peripheral blood mononuclear cells by western blotting. miR-30a was over expressed and Beclin 1 was under expressed in imatinib responders compared to resistant cases median 1.21(0.55-3.02) versus median 0.65 (0.03-1.0) (p = 0.001) and median 950.0 (400.0-2410.0) versus, median 1570.0 (920.0-5430.0) (p < 0.001) respectively. Beclin 1 correlated significantly positively with miR-30a in new cases (p = 0.001) and negatively in imatinib responders (p = 0.021). Receiver Operating Curves demonstrated the performances of miR-30a and Beclin 1 to detect imatinib resistance. They showed sensitivities of 97.14% and 94.29% and specificities of 53.33% and 42.22% at the cut-off values of 1 and 940 respectively. Both miR-30a and Beclin 1 levels showed a relation with imatinib response and can therefore be put forward as valuable markers for detection of resistance and may also have promising future therapeutic implications.

OP-31 - SH2-containing tyrosine phosphatase-1 (SHP-1) MRNA expression and its promoter methylation in imatinib response in Egyptian chronic myeloid leukemia patients

We described the clinical features and outcomes for 63 adult patients with acute myeloid leukemia (AML) with a translocation involving the 11q23 locus (MLL) who were treated at Memorial Sloan Kettering Cancer Center (MSK). The population included 40 female (63 %) and 23 male (37 %) patients, with a median age of 51 years old (range 18–82 years). Of the 31 patients who had had an antecedent malignancy, 14 (45 %) had had breast cancer or DCIS and 22 (71 %) had received anthracycline-based systemic chemotherapy. The translocation partner for the 11q23 rearrangement was identified in 60 of the 63 patients (95 %) studied. The distribution of translocation partners differed for those who had previously received cytotoxic chemotherapy. Most patients with therapy-related disease had a 9p22 or 19p13 partner, as compared to those with de novo disease (95 % vs. 68 %, p = 0.023). Of the 30 patients who received all therapy under observation, 15 (50 %) patients had de novo disease and 15 (50 %) had received antecedent chemotherapy. No significant difference in survival was observed between groups (p = 0.44). Twenty-two patients received induction as up-front therapy, of whom 11 (50 %) achieved CR / CRi. The achievement of CR / CRi with one course of induction was associated with improved OS, with a 6-month OS of 73 % as compared to 23 % for those who did not (p = 0.018). The achievement of CR / CRi with a single course of induction may be a marker of favorable survival in this subtype of high-risk AML.Response to a single induction was associated with favorable survival in this population.

Prognostic Impact of Additional Chromosomal Abnormalities in Egyptian Chronic Myeloid Leukemia Patients

Prognostic Impact of Additional Chromosomal Abnormalities in Egyptian Chronic Myeloid Leukemia Patients

PB1919 EFFECT OF OCT1 GENE POLYMORPHISM ON RESPONSE TO IMATINIB MESYLATE IN CML PATIENTS

Background: Imatinib mesylate (IM) has been shown to be highly efficacious in the treatment of Chronic Myeloid Leukemia (CML). Continuous and adequate dosing is essential for optimal outcomes. There is a considerable variability in the level of molecular responses achieved with IM therapy. These differences could result from variable drug level which may be due to genetic factors. The human organic cation transporter 1 (OCT1; SLC22A1) has been reported to be the main influx transporter responsible for active uptake of IM into CML cells. Aims: We hypothesized that the SNPs of this gene could predict the outcomes of IM therapy in CML patients. Methods: Fifty patients with CML at chronic phase were studied. All patients were monitored at outpatient clinic of the National Cancer Institute, Cairo University, Egypt. The study was approved by the NCI Ethical Committee for Clinical Research. Written Informed consent was obtained. The polymorphism of SLC22A1 gene was studied using PCR-RFLP technique. Imatinib mesylate level was determined using HPLC-massspectroscopy. Results: The mean IM trough plasma level in patients who achieved unfavorable response (n = 25) was 1019 ± 638 ng/mL, and in patients who achieved favorable response (n = 25) 1353 ± 611 ng/mL (p = 0.04). In regard to SLC22A1 rs(628031) gene, heterogeneous & variant allele (GA&AA) was significantly correlated to unfavorable response while wild allele GG is linked to favorable response(p = 0.0006). No significant correlation was detected between SLC22A1 gene polymorphism and drug level (p = 0.08). Summary/Conclusion: In patients with CML treated with IM, one of the significant factors affecting response was OCT1 polymorphism. This may influence the interindividual variation observed among Egyptian CML patients. Although a prospective study with a larger patient population is necessary to validate this finding. In patients with CML treated with IM, one of the significant factors affecting response was OCT1 polymorphism. This may influence the interindividual variation observed among Egyptian CML patients. Although a prospective study with a larger patient population is necessary to validate this finding.

Study of Additional Chromosomal Abnormalities in Young Adult Egyptian Chronic Myeloid Leukemia Patients

Background: Outcome in chronic myeloid leukemia (CML) have improved with tyrosine kinase inhibitor treatment (TKI). Additional chromosomal abnormalities (ACAs) are strongly associated with disease progression but their prognostic impact and influence on treatment response in young adults are yet to be defined. The aim of this study was to analyze the impact of ACAs in Egyptian young adult CML patients on response to treatment. Materials and methods: The data from the Hematology Department and outpatient clinic of Ain Shams University was collected from young adult CML. Results: At presentation, ACAS were found in 7 patients (8%). During treatment, 4 patients of them had achieved molecular response. While during treatment, ACAS were found in 10 patients. 4 patients of them had achieved molecular response. Also during treatment, chromosome 17 abnormalities were found in 4 patients.Three patients of them didn’t achieve molecular response and shifted to tasigna. Conclusion: ACAS at diagnosis and during treatment has no impact on CML poor risk parameters which denotes that other factors are more significant .Time to molecular response didn’t differ between ACAS +ve &-ve patients at diagnosis

Polymorphism of Human Organic Cationic Transporter1 (C480G) in Egyptian Chronic Myeloid Leukemia Patients on Imatinib

Background: Human organic cationic transporter1 (Hoct1) is a plasma membrane transporter responsible for the main influx of Imatinib into chronic myeloid leukemia (CML) cells. Single nucleotide polymorphisms (SNPs) in the gene coding for hOCT1 are important factors causing Imatinib resistance. We investigated the frequency of hOCT1 SNP C480G among Egyptian CML patients and its relation to early molecular response as an indicator of treatment outcome. Materials and Methods: Two groups of CML patients were included in this study. Group I consisted of 25 patients responding to Imatinib treatment (Imatinib responsive) and group II consisted of 25 patients resistant to Imatinib (Imatinib resistant). Response criteria were assessed according to the NCCN (National Comprehensive Cancer Network) guidelines 2017. Twenty healthy controls of matched age and sex were also included (group III). For all patients, we studied hOCT1 C480G at initial presentation using Taqman drug metabolism genotyping as well as BCR-ABL percent at diagnosis and after 3 months interval. Results: hOCT1 C480G was present in 32% of studied CML patients. CC (wild) was detected in 68% of group I and 64% of group II. CG (mutant heterozygous) was present in 28% of group I and 36% of group II while GG (mutant homozygous) was detected in only one case in group I. CG was also detected in 15% of control subjects There was no significant difference between hOCT1 C480G polymorphism and Early Molecular Response (χ2 = 0.089, p = 0.765). Conclusions: hOCT1 C480G polymorphism has no association with Imatinib resistance in Egyptian population. However, further studies on a larger number of patients are still needed to confirm this finding.

Influence of CYP3A5 and SLCO1 on Imatinib Response Among Egyptian Patients with Chronic Myeloid Leukemia in Chronic Phase

BackgroundImatinib (IM) was approved as a molecular target tyrosine kinase inhibitor (TKI) drug that selectively inhibits BCR/ABL1 tyrosine kinase which causes Philadelphia-positive chronic myeloid leukemia (CML) and so far has been one of the first-choice treatment option in CML with excellent results. However, only a proportion of patients achieve major molecular response. Hence, the need to find whether there are some factors that affect the response to treatment is essential. Although IM pharmacokinetics is influenced by several enzymes and transporters, little is known about the role of pharmacogenetic variation in IM metabolism. This study aimed to investigate the frequencies of mutational status of CYP3A5 and SLCO1 in CML patients undergoing imatinib treatment and to determine whether these two genes could predict the response to imatinib therapy in CML patients.Subjects and methodsWe investigated the mutational status of SLCO1 and CYP3A5 by Polymerase Chain Reaction followed by restricted fragment length polymorphism in 62 Philadelphia positive newly diagnosed Egyptian CML patients in chronic phase; 39 males (62.9%) and 23 females (37.1%). All patients received imatinib therapy and were followed up for at least one and half year. The response to imatinib therapy was evaluated by recording the hematological response, cytogenetic response at 3rd then 6th month and molecular response at 12th month according to the European Leukemia Net criteria. ResultsTwenty-eight patients (45.2%) were CYP3A5 wild versus 34 patients (54.8%) mutant while 26 patients (41.9%) were SLCO1 wild versus 36 patients (58.1%) mutant. 85.7% of patients with wild CYP3A5 had low & intermediate Sokal score versus 76.5% of mutant CYP3A5 patients had low & intermediate Sokal score with non-significant relation (p = 0.3). There was a significant relation between mutation in CYP3A5 and poor performance state (PS) of the patients at presentation; 89.3% of patients with wild CYP3A5 had good PS versus 61.8% in the mutant group with (p = 0.01). After 3 month of imatinib therapy there was no significant relation between CYP3A5 mutational state and response to therapy however, 85.7% of patients with wild CYP3A5 reached optimal & suboptimal response versus 79.4% in the mutant group with non-significant difference (p = 0.5). We had 51 patients that continued on imatinib till 6th month of therapy whereas 11 patients shifted to 2nd line TKI after imatinib failure. 87.5% of patients with wild CYP3A5 reached optimal & suboptimal response versus 66.7% in the mutant group with difference reaching significance (p = 0.07). We have 39 patients continued imatinib therapy till 12 month whereas 12 patients shifted to 2nd line TKI after imatinib failure. 71.4% of patients with wild CYP3A5 reached MMR at 12th month of treatment however only 22.2% of mutant CYP3A5 patients reached major molecular response (MMR) with significant difference (p = 0.002). Patients with wild SLCO1 were significantly had low & intermediate Sokal score (p = 0.04). However there was no significant correlation between SLCO1 mutational state and performance state or response to imatinib therapy.ConclusionCYP3A5 mutant gene was associated with poor imatinib efficacy while the SLCO1 gene was not associated with the response to imatinib treatment in Egyptian patients with CML in chronic phase. DisclosuresNo relevant conflicts of interest to declare.

The Utility and Applicability of Chronic Myeloid Leukemia Scoring Systems for Predicting the Prognosis of Egyptian Patients on Imatinib: Retrospective Study

Background: Chronic myeloid leukemia (CML) is myeloproliferative clonal neoplasm. Imatinib has greatly improved CML prognosis. Many prognostic scoring systems have been developed for CML risk stratification. In clinical practice, 3 systems are widely used: Sokal, Hasford and European Treatment Outcome Study (EUTOS). Recently, EUTOS long-term survival (ELTS) score is the first long-term scoring system that considered specifically CML-related death. Therefore, the aim of the present study was to validate the effectiveness of Sokal, Hasford, EUTOS and ELTS scoring systems in predicting the outcome in Egyptian CML-chronic phase (CML-CP) patients treated with imatinib. Patients and methods: Retrospective study performed on 167 patients with CML-CP who were treated with imatinib. Using the Sokal, Hasford, EUTOS and ELTS scores, we divided the patients into each risk groups. Results: Significant differences in event free survival (EFS), time without progression (TWP) and overall survival (OS) prediction between the Sokal, Hasford and ELTS risk groups, but no significant difference among the EUTOS score risk groups. Conclusion: Our study indicates that Sokal, Hasford and ELTS scoring systems but not the EUTOS score are effective in predicting early treatment response, EFS, TWP and OS for Egyptian CML patients treated with imatinib

Detection of BCR/ABL Translocation in Bone Marrow Derived Mesenchymal Stem Cells in Egyptian CML Patients.

BACKGROUND:Chronic myeloid leukemia (CML) is a clonal myeloproliferative disorder of hematopoietic stem cells. It is characterized at the cytogenetic level by Philadelphia (ph) chromosome and at the molecular level by the BCR/ABL gene rearrangement. Bone marrow derived mesenchymal stem cells (MSCs) are pluripotent stem cells that can differentiate into several mesenchymal tissues.AIM:To observe the biological characteristics of MSCS from CML patients and to determine whether MSCs harbor the abnormal BCR/ABL translocation similar to CML bone marrow cells.SUBJECTS AND METHODS:Characterized MSCs were isolated from 12 newly diagnosed Philadelphia positive untreated CML patients.RESULTS:MSCs can be readily isolated from CML marrow and exhibit major expansion. Flow cytometry analysis revealed the typical MSC phenotype. Moreover; MSCs do not harbor the BCR/ABL translocation confirmed by karyotype and real time PCR.CONCLUSION:MSCs from CML patients express the typical MSC phenotype; and do not express the BCR/ABL gene. Since; MSCs are able to support engraftment of hematopoietic stem cells in stem cell transplantation(SCT) as well as suppress alloreactive T cells causing graft versus –host disease, this current study provides evidence that in a SCT setting of CML patients, autologous MSCs could be a source of stem cell support in future cell therapy applications.

Basophil progenitor marker histamine and its relation to the treatment response in Egyptian chronic myeloid leukemia patients

Introduction Chronic myeloid leukemia (CML) is characterized by the presence of the BCR-ABL fusion gene with constitutive tyrosine kinase activity that activates many signaling pathways contributing to the abnormal growth and survival of leukemic cells. Basophilia is a strong independent prognostic variable that correlates with the phase of CML. In CML, basophils are difficult to be identified by their morphology due to their immaturity or low frequency by tyrosine kinase inhibitors (TKIs) therapy. It is important to predict responses to therapy and to monitor levels of minimal residual disease in CML patients by cytogenetics and PCR. However, these parameters are expensive and require special technologies. Thus, the aim of the current study was to clarify whether the serum level of the basophil-marker histamine correlates with hematologic, cytogenetic, and molecular responses in CML patients and with the achievement of the optimal response to TKI therapy. Patients and methods The histamine level was measured by enzyme-linked immunosorbent assay in 48 CML patients, together with cytogenetic analysis at diagnosis and after 6 months from the start of imatinib treatment. Molecular study of BCR-ABL was also performed at 6 months. Results Histamine levels were upregulated in CML patients at diagnosis compared with the healthy control group and correlated with the total leukocytic count, the absolute peripheral blood basophil count, and the percent of bone marrow basophils. After 6 months of imatinib treatment, histamine levels were significantly reduced in CML patients compared with the levels at diagnosis and were still significantly higher than in controls. Histamine levels at 6 months correlated significantly with PCR measurements for BCR-ABL . A significant difference in histamine levels was found between patients according to their hematological, cytogenetic, and molecular responses. Also, it differed significantly among TKI response groups (optimal, warning, failure). Conclusion We found that the serum histamine level may serve as a cheap early predictor of cytogenetic and molecular remission as well as the response to imatinib. However, we could not encourage measuring serum histamine as an alternative to PCR for BCR-ABL for the monitoring of minimal residual disease.

Association of MDR1 gene polymorphism (G2677T) with imatinib response in Egyptian chronic myeloid leukemia patients

BackgroundDespite the excellent efficacy results of imatinib treatment in CML patients, resistance to imatinib has emerged as a significant problem. Genetic variations in genes involved in drug transportation might influence the pharmacokinetic and metabolism of imatinib. The genotype of a patient is increasingly recognized in influencing the response to the treatment.AimTo investigate the genotype frequencies of single nucleotide polymorphisms (SNPs) G2677T in CML patients undergoing imatinib treatment to determine whether different genotype pattern of these SNPs have any influence in mediating response to imatinib.MethodsA total of 96 CML and 90 control samples were analyzed for the human multidrug resistance gene 1 (MDR1) gene polymorphism (G2677T) using polymerase chain reaction-restriction fragment length polymorphism technique.ResultsGenotype distribution revealed a significant lower frequency of TT genotype in CML patients and non-significant difference in the GG, GT genotype frequencies between patients and controls (P = 0.004, 0.138, 0.210, respectively). GG genotype was significantly higher in chronic phase (P = 0.046), while GT genotype was significantly higher in Blastic crisis phase (P = 0.002). There was a significant difference in genotype frequency of G2677T among patients showing response and resistance to imatinib in chronic phase (P = 0.02). TT genotype was associated with complete hematological response (P = 0.01), complete cytogenetic response (P < 0.001), and better molecular response with a significant association (P < 0.001). GT genotype was associated with partial hematological response (P = 0.01) and minor cytogenetic response (P < 0.001). Optimal and suboptimal responses were observed for patients with TT genotype (P = 0.003). Failure of drug response was associated with GT genotype (P = 0.02); however, GG had no association with drug response. Multivariate analysis considered GT genotype as independent risk factor for resistance (P = 0.037), while TT genotype as protective factor against resistance to imatinib (P = 0.008).ConclusionDetermination of MDR1 polymorphisms (G2677T) might be useful in response prediction to therapy with imatinib in patients with CML.

Do SLCO1B3 (T334G) and CYP3A5*3 polymorphisms affect response in Egyptian chronic myeloid leukemia patients receiving imatinib therapy?

BackgroundImatinib has so far been the first-choice treatment in chronic myeloid leukemia (CML) with excellent results. However, only a proportion of patients achieve major molecular response. Hence, the need to find whether there are some factors that affect the response to treatment is essential. This study aimed to investigate the allele and genotype frequencies of single nucleotide polymorphisms (SNPs) of SLCO1B3 (T334G) and CYP3A5*3 in CML patients undergoing imatinib treatment and to determine whether SNPs of these two genes could predict the response of imatinib therapy in CML patients.Subjects and methodsWe investigated SLCO1B3 (T334G) and CYP3A5*3 polymorphisms by Polymerase Chain Reaction-restriction fragment length polymorphism in 86 Philadelphia positive newly diagnosed Egyptian CML patients (78 patients in chronic phase and 8 patients in accelerated phase). All patients received imatinib therapy and were followed for at least one and half years. The response to imatinib therapy was evaluated by recording the hematological response, cytogenetic response, and molecular response according to the European Leukemia Net criteria.ResultsThis study included 86 Philadelphia positive newly diagnosed CML patients, 78 in the early chronic phase and 8 in the accelerated phase. In the chronic phase patients, no association between SLCO1B3 (T334G) exon 3 polymorphism and response to imatinib therapy was detected (P = 0.938) while CYP3A5*3 gene polymorphism was associated with inferior outcome (P < 0.001). In the group of accelerated phase patients, the SLCO1B3 polymorphic variants (TG) and (GG) were detected equally with none of the patients in this group having the homozygous wild form (TT). The homozygous state for the CYP3A5*3 allele was the most frequent (50%) and the homozygous state for the CYP3A5*1 allele was the least frequent (12.5%) in this group.ConclusionCYP3A5*3 polymorphism was associated with imatinib efficacy while the SNP SLCO1B3 (T334G) was not associated with the response to imatinib treatment in Egyptian patients with CML in chronic phase. These results prompt us to explore the effect of CYP3A5*3 in CML patients taking imatinib in a larger scale study.

Abl Kinase Domain Mutations in Imatinib-treated Egyptian Patients with Chronic Myeloid Leukemia

Background: Point mutations within ABL kinase domain (AKD) of the BCR-ABL gene are the most common cause of resistance to Imatinib Mesylate (IM) treated Chronic Myeloid Leukemia (CML) patients. Objectives: To assess the frequency, type and impact of AKD mutations on prognosis in a cohort of Egyptian CML patients. Patients and methods: Serial measurements of BCR-ABL transcripts level in 175 IM treated CML patients were performed using real time quantitative polymerase chain reaction (RQ-PCR). Mutation screening was performed by allele specific oligonucleotide polymerase chain reaction (ASO-PCR) in 72 patients including all 42 non-optimal responders; 28 resistant patients, 18 suboptimal responders in addition to 30 patients randomly selected with stable/ decreasing transcript level representing an optimal responder category. Results: AKD mutations were detected in 16/28 resistant patients (57%) at time of >2-fold rise in BCR-ABL transcript and in none of the 44 optimal or suboptimal responders (0%) with decreasing or stable transcript levels. From 16 positive patients, P-loop mutations were detected in 9 patients; Q252H in 3 patients (19%), Y253H in 2 patients (12%), Y253F in 2 patients (12%) and E255K in 2 patients (12%). T315I was detected in 1/16 (6%) patient. Regarding non P-loop mutation; V299L was detected in one patient (6%), M351T in 4 patients (25%), F359V in 2 patients (12%). One patient had both Y253H and E255K mutations. Ten/16 (62%) patients carrying mutations experienced disease progression versus 1/56 (2%) in non mutation group (p=0.001). Median progression free survival (PFS) and overall survival (OS) of the mutation group was 13.5 months and 37.5 months, respectively versus 42.6 months in non mutation group (p=0.001). The estimated PFS and OS at 49 months in patients with mutations were 37.5% and 56.3% respectively versus 98.2% in non mutation carriers (p 2-folds in IM resistant patients may signal progression that implies testing for AKD mutations and early planning for second generation tyrosine kinase inhibitors (TKIs). P-loop mutations are significantly associated with advanced CML phases and poorer OS than non-P loop mutations. ASOPCR is a valuable tool for detection of mutations in countries where sequencing facilities are not available.

CYP1A1, GSTM1 and GSTT1 Genetic Polymorphism in Egyptian Chronic Myeloid Leukemia Patients

CYP1A1, GSTM1 and GSTT1 Genetic Polymorphism in Egyptian Chronic Myeloid Leukemia Patients