Frequencies of BCR-ABL1 fusion transcripts among Sudanese chronic myeloid leukaemia patients (original) (raw)
Related papers
Frequency of BCR-ABL 1 Fusion Transcripts Variants in Chronic Myeloid Leukemia Algerian patients
Journal de la faculté de médecine d'Oran, 2017
Objectif-Dans le contexte de la leucémie myéloïde chronique (LMC), la recherche du transcrit de fusion BCR-ABL1 est devenue indispensable pour confirmer le diagnostic moléculaire. Dans cette étude, nous décrivons les différents types de transcrits de fusion BCR-ABL1 retrouvés chez des patients de l'Ouest algérien atteints de leucémie muéloïde chronique (LMC). Méthodes-Au total 167 patients suspects de LMC ont été inclus dans cette étude. La recherche qualitative des transcrits de fusion a été réalisée au service de biochimie de l'Etablissement hospitalier et universitaire d'Oran, par la technique d'amplification en chaine par polymérase après rétro-transcription (RT-PCR). Résultats-Les deux types de transcrits de fusion BCR-ABL1de type majeur Mb3a2 et Mb2a2 étaient présents respectivement dans 59,8 et 36.4 % des cas. Deux patients (1,8%) avaient un transcrit atypique rare de type e19a2 et deux autres (1,8%), ont co-exprimé les deux types b3a2 et b2a2. Conclusion-Notre étude a confirmé les données de la littérature en montrant une incidence plus élevée du transcrit majeur.
Caspian Journal of Internal Medicine, 2018
Background: A specific chromosomal abnormality, the Philadelphia chromosome (BCR-ABL fusion), is present in all patients with chronic myeloid leukemia (CML). The b2a2 and b3a2 fusion mRNAs encode p210 fusion protein p210 and e1a2 encode p190. The aim of this study was to evaluate the frequency of BCR-ABL fusion transcript variants in Northeast of Iranian CML patients and to compare the laboratory results of our patients. Methods: This study was conducted in 85 peripheral blood and bone marrow samples of CML patients. Ribonucleic acid (RNA) was extracted by a commercial kit, RT-PCR for identifying BCR-ABL fusions was carried out by using designed primers and the PCR products were electrophoresed in agarose gels. Finally, statistical analysis was performed for variant frequency identification and their comparison was performed. Results: All patients examined were positive for BCR/ABL rearrangement. Fusion of b3a2 was detected in 53 (62.35%) patients, b2a2 in 25 (29.41), e1a2 in 1 (1.17%) and coexpression of b3a2 and e1a2 in 6 (7.05%) patients. There were significant differences between the mean age in patients with b3a2 positive (44.07 years) and in b3a2 negative group (50.35 years) however, no significant differences were seen between sex and b2a2 (P=0.61), b3a2 (P=0.79) and e1a2 (P=0.20). Conclusions: This study showed higher frequency b3a2 than b2a2 and e1a2 transcripts in CML patients in Northeast Iran and there was no association between e1a2 transcripts frequencies and monocytosis in peripheral blood.
Iranian Journal of Blood and Cancer, 2018
Background: The Philadelphia chromosome (Ph) characterized by t (9; 22) (q34; q11.2) is a reciprocal translocation giving rise to a chimeric BCR-ABL fusion gene. Incidence of Ph chromosome is over 98% in Patients with Chronic Myeloid Leukemia (CML) and around 20% in acute lymphoblastic leukemia (ALL). The finding of this fusion gene is essential for diagnosis of CML by detection of various fusion transcripts such as b2a2 and b3a2 transcripts and Ph positive ALL by detection of e1a2 (p190) transcripts. We conducted this study to determine the frequency of various BCR-ABL fusion transcripts in the west Azerbaijani patients with CML. Methods: RNA was isolated from peripheral blood samples by standard protocols. BCR-ABL fusion gene detection was carried out with one-step multiplex RT-PCR in 41 west Azerbaijani patients with CML. Results: Among patients with CML, the frequencies of b2a2 and b3a2 transcripts were 52.5% and 12.5%, respectively. Co-expression of b3a2 and b2a2 transcripts wa...
Frequency of BCR-ABL fusion transcripts in Serbian patients with chronic myeloid leukemia
Journal of B.U.ON. : official journal of the Balkan Union of Oncology
The aim of this study was to analyze the occurrence of the most frequent BCR-ABL transcript variants (b3a2, b2a2 and e1a2) in Serbian patients with chronic myeloid leukemia (CML) and compare it with the occurrence reported in other populations. We analyzed peripheral blood and bone marrow samples of 136 Serbian patients with CML by RT-PCR and cytogenetic methods. In 100 patients (73.5%) the b3a2 and in 34 (25%) the b2a2 forms of BCR-ABL were detected. One (0.75%) patient was BCR-ABL negative, but in lymphoblastic transformation he expressed the e1a2 [corrected] transcript of BCR-ABL. One (0.75%) patient displayed both b2a2 and b3a2 forms of BCR-ABL. Analysis of this group according to karyotype showed b3a2 predominance (79%) in patients with classic t(9;22); b2a2 was found in 20% and both b2a2 and b3a2 forms in 1%. In variant translocations b3a2 in 65% and b2a2 in 35% of the patients were detected. In contrast, the subgroup with normal karyotype expressed slight predominance of the ...
Frequency of BCR-ABL Fusion Transcripts in Iranian Patients with Chronic Myeloid Leukemia
Archives of Iranian Medicine, 2008
Background: A specific chromosomal abnormality, the Philadelphia chromosome, is present in 90 -95% of patients with chronic myeloid leukemia. The aberration results from a reciprocal translocation of chromosomes 9 and 22, creating a BCR-ABL fusion gene. There are two major forms of the BCR-ABL fusion gene, involving ABL exon 2, but including different exons of BCR gene. The transcript b2a2 or b3a2 codes for a p210 protein. Other fusion gene leads to the expression of an e1a2 transcript, which codes for a p190 protein. Other less common fusion genes are b3a3 or b2a3 (p203) and e19a2 (p230). The incidence of one or other rearrangement in chronic myeloid leukemia patients varies in different reports. In general, fusion transcripts are determined individually, a process which is labor-intensive in order to detect all major fusion transcripts. The objective of this study was to set up a multiplex RT-PCR assay for detection and to determine the frequency of different fusion genes in 75 Iranian patients with chronic myeloid leukemia.
Characteristics of BCR–ABL gene variants in patients of chronic myeloid leukemia
Open Medicine
Background Depending on breakpoints of rearrangement different types of BCR–ABL fusion protein can be generated in patients of chronic myeloid leukemia (CML). The aim of this study is to observe frequencies of major transcripts in CML patients by reverse transcriptase polymerase chain reaction (RT-PCR) and their hematological features at the time of presentation. Materials and methods This cross sectional study was performed at Molecular Lab of Riphah International University, Islamabad from January to June 2019. Consecutive peripheral blood samples of 70 newly diagnosed CML patients in chronic phase were analyzed by RT-PCR to detect different BCR–ABL transcripts. Routine blood cell counts were assessed by an automated hematology analyzer. Results All samples expressed typical BCR–ABL rearrangement. Expression of either e14a2 or e13a2 transcript was detected in 38 (54%) and 30 (43%) patients, respectively. Coexpression of e13a2 + e14a2 was found in 2 (3%) patients. The mean total le...
Asian Pacific journal of cancer prevention : APJCP, 2015
Chronic myeloid leukemia (CML) is a myeloproliferative disorder of pluripotent stem cells, caused by reciprocal translocation between the long arms of chromosomes 9 and 22, t(9;22)(q34;q11), known as the Philadelphia chromosome. A total of 51 CML patients were recruited in this study. Complete blood counts of all CML patients were performed to find out their total leukocytes, hemoglobin and platelets. FISH was performed for the detection of BCR-ABL fusion and cryptogenic tests using bone marrow samples were performed for the conformation of Ph (9;22)(q34;q11) and variant translocation mechanisms. In cytogenetic analysis we observed that out of 51 CML patients 40 (88.9%) were Ph positive and 4 (8.88%) had Ph negative chromosomes. Mean values of WBC 134.5 103/μl, hemoglobin 10.44 mg/dl, and platelets 288.6 103/μl were observed in this study. In this study, Ph positive translocation between chromosome (9:22)(q34;q11) were observed in 40 (88.9%) CML patients.
BCR/ABL p210, p190 and p230 fusion genes in 250 Mexican patients with chronic myeloid leukaemia (CML
Clinical and Laboratory Haematology, 2002
There are two major forms of the BCR/ABL fusion gene, involving ABL exon 2, but including different exons of BCR gene. The transcripts b2a2 or b3a2 code for a p210 protein. Another fusion gene leads to the expression of an e1a2 transcript, which codes for a p190 protein. Another, less common fusion gene is c3a2[e19a2], which encodes a p230 protein. The incidence of one or the other rearrangement in chronic myeloid leukaemia (CML) patients varies in different reported series. This study was designed to determine the frequency of coexpresion of the p210, p190 and p230 transcripts in 250 Mexican patients with CML. We performed nested and multiplex reverse transcriptase polymerase chain reaction (RT-PCR) on bone marrow samples from adult patients and found that all cases were positive for some type of BCR/ABL rearrangement. In 226 (90.4%) patients it was p210, while the remaining 9.6% showed coexpression or one of the transcripts of p190/p210/p230. In 7% of patients with p210 expression there are both isoforms (b3a2/b2a2), presumably the result of alternative splicing. The rate of coexpression of the p190/p210 transcripts was 5%, which is much lower than in other reports. This may be due to the technical factors. These patients had high platelet counts, marked splenomegaly and chromosomal abnormalities in addition to Ph¢. Other types of coexpression seen were p210/p230 and p190/p210/p230, in patients with high-risk clinical factors. Our study confirms the occurrence of coexpression of different BCR/ABL transcripts, although the rate (9.6%) was much lower than has been reported in other populations. This may reflect either the sensitivity of the detection techniques used or the possibility of genetic differences between the populations studied. Coexpression may be due to alternative splicing or to phenotypic variation, with clinical courses different from classical CML.
Heterogeneity of BCR-ABL rearrangements in patients with Chronic Myeloid Leukemia in Pakistan
Pakistan Journal of Medical Sciences, 2014
Background and Objective: Breakpoint cluster region-Abelson (BCR-ABL) rearrangement or Philadelphia (Ph) chromosome in Chronic Myeloid Leukemia (CML) is derived from a reciprocal chromosomal translocation between ABL gene on chromosome 9 and BCR gene on chromosome 22. This chimeric protein has various sizes and therefore different clinical behaviour. The purpose of this study was to determine the heterogeneity of BCR-ABL rearrangement in patients with Ph + CML in Pakistan. Methods: The study was conducted at Civil Hospital and Baqai Institute of Hematology (BIH) Karachi. Blood samples from 25 patients with CML were collected. Multiplex reverse transcription polymerase chain reaction (RT-PCR) was performed to identify various BCR-ABL transcripts. Results: All 25 samples showed BCR-ABL rearrangements. Out of these, 24 (96%) patients expressed p210 BCR-ABL rearrangements i.e. 60% (n=15) had b3a2 and 32% (n=8) had b2a2 rearrangements. Co-expression of b3a2 /b2a2 rearrangement and p190 (e1a3) rearrangement was also identified in two patients. Conclusion: It is apparent that majority of the patients had p210 BCR-ABL rearrangements. Frequency of co-expression and rare fusion transcripts was very low.
Distribution of BCR–ABL1 Transcript Variants in Nigerians with Chronic Myeloid Leukemia
Indian Journal of Hematology and Blood Transfusion, 2020
The distribution of BCR-ABL1 transcript variants e13a2 (''b2a2'') and e14a2 (''b3a2'') in Nigerians with chronic myeloid leukemia (CML) had not been previously studied. In addition, there is paucity of data on the impact of BCR-ABL1 transcript variants on clinical presentation and survival in CML patients in Nigeria. The BCR-ABL1 transcript variants were analyzed in 230 Imatinib-treated CML patients at diagnosis. Patients with incomplete data (n = 28), e19a2 (n = 3) and e1a2 (n = 1) were excluded from analysis of transcript variant on disease presentation and survival leaving only 198. The frequencies of BCR-ABL1 transcript variants were 30 (13.0%), 114 (49.6%), 82 (35.7%), three (1.3%) and one (0.4%) for e13a2, e14a2, coexpression of e13a2/e14a2, e19a2 and e1a2, respectively. A significantly higher platelet count was found in patients with e13a2 variant (531.1 ± 563.4 9 10 9 /L) than in those expressing e14a2 (488.2 ± 560.3 9 10 9 /L) or e13a2/e14a2 (320.7 ± 215.8 9 10 9 /L); p = 0.03. No significant differences were found between the variants with regards to gender, age, phase of disease at diagnosis, total white blood cell count, neutrophil percentage, hematocrit, splenomegaly or hepatomegaly. Overall survival was higher but not statistically significant (p = 0.4) in patients with e14a2 variant (134 months) than in e13a2 (119 months) and coexpression of e13a2/e14a2 (115 months). Nigerian CML patients have the highest incidence of co-expression of e13a2 and e14a2. Distinct disease characteristics which contrast with findings from the Western countries were also identified in Nigerians which may be due to genetic factors.