Detection of kinase domain mutations in BCR::ABL1 leukemia by ultra-deep sequencing of genomic DNA.

The screening of the BCR::ABL1 kinase domain (KD) mutation has become a routine analysis in case of warning/failure for chronic myeloid leukemia (CML) and B-cell precursor acute lymphoblastic leukemia (ALL) Philadelphia (Ph)-positive patients. In this study, we present a novel DNA-based next-generation sequencing (NGS) methodology for KD ABL1 mutation detection and monitoring with a 1.0E-4 sensitivity. This approach was validated with a well-stablished RNA-based nested NGS method. The correlation of both techniques for the quantification of ABL1 mutations was high (Pearson r = 0.858, p < 0.001), offering DNA-DeepNGS a sensitivity of 92% and specificity of 82%. The clinical impact was studied in a cohort of 129 patients (n = 67 for CML and n = 62 for B-ALL patients). A total of 162 samples (n = 86 CML and n = 76 B-ALL) were studied. Of them, 27 out of 86 harbored mutations (6 in warning and 21 in failure) for CML, and 13 out of 76 (2 diagnostic and 11 relapse samples) did in B-ALL patients. In addition, in four cases were detected mutation despite BCR::ABL1 < 1%. In conclusion, we were able to detect KD ABL1 mutations with a 1.0E-4 sensitivity by NGS using DNA as starting material even in patients with low levels of disease.

C>A substitution in NT 46 of the 3' UTR region (the α complex protected region) of the alpha-1 globin gene: a non-deletional mutation or polymorphism?

AIMS: Untranslated regions (UTRs) play an important role in post-transcriptional regulation of gene expression, including by modulating messenger RNA (mRNA) transport out of the nucleus, translation efficiency, subcellular localisation and stability. Any mutation in this region could alter the stability of mRNA and thereby affect protein synthesis. We analysed if a mutation located in the α complex protected region of the α1 globin gene could cause non-deletional α-thalassaemia by affecting post-transcriptional stability (mRNA stability). METHODS: A total of 14 patients without anaemia, normal or slight microcytosis and hypochromia (medium concentration haemoglobin [MCH] <27 pg) were studied. Haemoglobin subtypes were screened using capillary zone electrophoresis and ion-exchange high-performance liquid chromatography (VARIANT II ß-Thalassaemia Short Program). The most common α-globin mutations were identified by multiplex PCR (Alpha-Globin StripAssay kit) and the molecular characterisation by automatic sequencing of alpha globin genes. RESULTS: All of them shown a novel transversion mutation in nt 778 (C>A), which is located in the 3' UTR in the α complex protected region [HBA1: c.*+46C>A]. CONCLUSIONS: This mutation is in the αRNAmin binding site, so a single nucleotide substitution in this region can decrease mRNA stability by potentially compromising the binding of α-complex protein to αRNAmin, favouring the decay of α-globin mRNA via erythroid cell-enriched endoribonuclease cleavage. In this case, it is a non-deletional α-thalassaemia. However, in silico and empirical studies predicted that it could be a silent polymorphism. Functional studies should be carried out to confirm whether it is a pathological mutation or a silent polymorphism.

Rivaroxabán en síndrome antifosfolipídico tras fracaso con acenocumarol: a propósito de 2 casos / After failure with acenocoumarol, rivaroxaban in antiphospholipid syndrome: a report of 2 cases

El síndrome antifosfolipídico se caracteriza por abortos o fenómenos trombóticos asociado a anticuerpos específicos. El tratamiento se basa en la anticoagulación con los antagonistas de la vitamina K. Presentamos 2 casos en los que el empleo del rivaroxabán ha logrado controlar la enfermedad tras su fracaso con acenocumarol

Antiphospholipid syndrome is characterized by abortions or thrombotic phenomena associated with specific antibodies. Anticoagulant therapy is based on vitamin K antagonists. We present two cases in which the use of rivaroxaban achieved control of the disease after the failure of acenocoumarol

After failure with acenocoumarol, rivaroxaban in antiphospholipid syndrome: A report of 2 cases. / Rivaroxabán en síndrome antifosfolipídico tras fracaso con acenocumarol: a propósito de 2 casos.

Antiphospholipid syndrome is characterized by abortions or thrombotic phenomena associated with specific antibodies. Anticoagulant therapy is based on vitamin K antagonists. We present two cases in which the use of rivaroxaban achieved control of the disease after the failure of acenocoumarol.

Incidence and clinical characteristics of myeloproliferative neoplasms displaying a PDGFRB rearrangement.

OBJECTIVES: The myeloproliferative neoplasms displaying a PDGFRB rearrangement are rare diseases derived from a haematopoietic stem cell. The goals of the study were to assess the incidence of these disorders and to define the clinical and biological characteristics as well as the response to the imatinib therapy. METHODS: A total of 556 patients with myeloproliferative neoplasms were studied by means of molecular cytogenetics. RESULTS: The incidence of myeloproliferative neoplasms (MPN) with PDGFRB rearrangement was low (10 cases, 1.8% of all MPN). Most of the patients showed moderate anaemia (median Hb was 10.0 gr/dL; range from 7.5 to 13 g/dL), leukocytosis (median white blood cells was 21.7 × 10(9) /L with a range from 4 to 43 × 10(9) /L) and eosinophilia (median circulating eosinophils was 2.4 × 10(9) /L with a range of 1.1-5.7 × 10(9) /L) with a median of bone marrow infiltration cells displaying PDGFRB rearrangement of 55% (range, 37-85%). In three cases, a t(5;12) was observed while two patients showed rearrangements of 17q21 region. In two cases, a del(5)(q31) was observed. Most of the patients responded to standard dosage of imatinib, and the response was maintained in the time in those patients with a follow-up higher than 9 years. CONCLUSIONS: The incidence of patients with PDGFRB rearrangement is low. These patients showed leukocytosis with eosinophilia and anaemia. The efficacy of imatinib therapy in patients showing PDGFRB rearrangement is high. For this reason, in all patients with MPN without any other molecular aberration, PDGFRB rearrangement should be ascertained.