| Autor: |
Cruz SSD; Laboratory of Molecular Biology, Ophir Loyola Hospital, Belém 66063-240, Brazil.; Human Cytogenetics Laboratory, Biological Science Institute, Federal University of Pará, Belém 66075-110, Brazil., Seabra AD; Laboratory of Molecular Biology, Ophir Loyola Hospital, Belém 66063-240, Brazil., Macambira LHR; Laboratory of Molecular Biology, Ophir Loyola Hospital, Belém 66063-240, Brazil., Carneiro DM; Laboratory of Molecular Biology, Ophir Loyola Hospital, Belém 66063-240, Brazil., Nunes PF; Laboratory of Molecular Biology, Ophir Loyola Hospital, Belém 66063-240, Brazil., Pontes TB; Laboratory of Molecular Biology, Ophir Loyola Hospital, Belém 66063-240, Brazil., Mello-Junior FAR; Laboratory of Molecular Biology, Ophir Loyola Hospital, Belém 66063-240, Brazil., Leão LBC; Department of Hematology, Ophir Loyola Hospital, Belém 66063-240, Brazil., Cordeiro FNCDS; Department of Hematology, Ophir Loyola Hospital, Belém 66063-240, Brazil., Carneiro TX; Department of Hematology, Ophir Loyola Hospital, Belém 66063-240, Brazil., Moreira-Nunes CA; Laboratory of Molecular Biology, Ophir Loyola Hospital, Belém 66063-240, Brazil.; Pharmacogenetics Laboratory, Department of Medicine, Drug Research and Development Center (NPDM), Federal University of Ceará, Fortaleza 60430-275, Brazil.; Northeast Biotechnology Network (RENORBIO), Itaperi Campus, Ceará State University, Fortaleza 60740-903, Brazil., Burbano RMR; Laboratory of Molecular Biology, Ophir Loyola Hospital, Belém 66063-240, Brazil.; Human Cytogenetics Laboratory, Biological Science Institute, Federal University of Pará, Belém 66075-110, Brazil. |
| Abstrakt: |
The Philadelphia (Ph+) chromosome, t(9;22)(q34;q11.2), originates from a chimeric gene called BCR-ABL and is present in more than 90% of CML patients. Most patients with CML express the protein p210 BCR-ABL and, with a frequency lower than 5%, express rare isoforms, the main one being p190. In the transition from the chronic phase to the blast phase (BP), additional chromosomal abnormalities, such as the presence of the double Ph+ chromosome, are revealed. Of the 1132 patients analyzed via molecular biology in this study, two patients (0.17%) showed the co-expression of the p210 and p190 isoforms for the BCR-ABL transcript, with the concomitant presence of a double Ph+ chromosome, which was observed via conventional cytogenetics and confirmed by fluorescent in situ hybridization. The BCR-ABL / ABL % p210 and p190 ratio increased in these two patients from diagnosis to progression to blast crisis. To our knowledge, this is the first report in the literature of patients who co-expressed the two main BCR-ABL transcript isoforms and concomitantly presented Ph+ chromosome duplication. The evolution from the chronic phase to BP often occurs within 5 to 7 years, and, in this study, the evolution to BP was earlier, since disease-free survival was on average 4.5 months and overall survival was on average 9.5 months. The presence of the p190 transcript and the double Ph+ chromosome in CML may be related to the vertiginous progression of the disease. |
