RESUMEN
Chronic myeloid leukemia (CML) is characterized by BCR-ABL translocation and an increased number and migration of immature myeloid cells into the peripheral blood. The detection limit of the BCR-ABL transcript, particularly after treatment, is controversial. In the present study, we used quantitative real-time reverse transcription-polymerase chain reaction (RT-qPCR) to monitor BCR-ABL expression in Moroccan CML patients undergoing imatinib treatment, and compared the results with those of conventional PCR and fluorescence in situ hybridization (FISH). The aim of this study was to establish a new molecular tool for in vitro diagnosis of CML. In a retrospective comparative analysis, 20 CML Moroccan patients who had received imatinib treatment (N = 20) were analyzed by real-time PCR, conventional RT-PCR, and FISH. Half of the samples analyzed (N = 10) were positive for BCR-ABL gene expression, while the other half (N = 10) were negative according to conventional PCR. Interestingly, 5 of the 10 samples shown to be negative by conventional PCR showed positive expression of the BCR-ABL gene according to RT-qPCR. The RT-qPCR results were confirmed by FISH, which revealed a high concordance (100%) rate. We found that real-time RT-qPCR is more reliable and should be used in Moroccan biomedical analysis laboratories to monitor CML progression, particularly for minimal residual disease, following imatinib treatment.
Asunto(s)
Proteínas de Fusión bcr-abl/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/sangre , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Neoplasia Residual/sangre , Neoplasia Residual/genética , Adulto , Anciano , Femenino , Proteínas de Fusión bcr-abl/sangre , Humanos , Mesilato de Imatinib/efectos adversos , Hibridación Fluorescente in Situ , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Masculino , Persona de Mediana Edad , Marruecos , Neoplasia Residual/inducido químicamente , Neoplasia Residual/patología , Patología Molecular , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios RetrospectivosRESUMEN
Germline mutations in the BRCA1 gene are known predictive markers for the development of hereditary breast cancer. Nevertheless, no comprehensive study has been performed targeting the presence and relevance of BRCA1 mutations in Moroccan breast cancer patients. We here present an analysis of BRCA1 gene regions (exon 2 and exon 11a/b) of 50 female Moroccan breast cancer patients with early disease onset (≤ 40 years) or familial disease backgrounds. Results showed that no mutation was present in either exon 2 or exon 11a of the BRCA1 gene in any of the 50 patients analysed. However, in exon 11b, a mutation generated by a nucleotide exchange was detected in 8% of patients, most of whom were young women (≤ 40). This mutation leads to substitution of the amino acid glutamine by an arginine at position 356 of the polypeptide sequence (Q356R). Although this mutation was previously characterised at a lower frequency in western populations, our study is the first to describe it in a young Moroccan population. Furthermore, another mutation was detected with a high frequency (4%) on exon 11b of the BRCA1 gene in exclusively young patients (≤ 40). This mutation was silent, encoding the same threonine residue at position 327 (T327T) as the wild type. The present study is the first to describe this mutation as well, particularly in a young Moroccan population. Analysis of a larger population is required in order to highlight the relevance of the Q356R and T327T mutations in young Moroccan breast cancer patients.