Prognostic and therapeutic stratification in CLL: focus on 17p deletion and p53 mutation.

Chronic lymphocytic leukemia (CLL), a disorder for which B cell heterogeneity and increased cellular proliferation play central pathogenic roles, displays several genetic abnormalities that are associated with poor prognosis and have therapeutic implications. In this review, we discuss the prognostic role and therapeutic implications of chromosome 17p deletions and TP53 mutations in CLL. Unlike other recurrent genetic abnormalities, the frequency of TP53 alterations is relatively low in newly diagnosed patients, but increases sharply with disease progression, which suggests that these alterations represent an evolutionary mechanism of resistance. In comparison with patients without such abnormalities, those with 17p deletions and TP53 mutations have lower response rates and more aggressive disease. One important consequence of the diverse molecular mechanisms that affect the TP53 pathway is the need to assess both the presence of 17p deletion and TP53 mutations before treatment initiation. Several authors have attempted to incorporate TP53 abnormalities in different prognostic models for CLL, and the recent International Prognostic Index for Chronic Lymphocytic Leukemia formally considers patients with TP53 abnormalities (deletion 17p or TP53 mutation or both) as high-risk. Several novel agents may improve results in patients with CLL, including in those with TP53 mutations. Ibrutinib, idelalisib, and venetoclax have been approved in various settings and countries for treatment of CLL. Further progress in targeted therapy and judicious use of chemotherapy, monoclonal antibodies, and reduced-intensity allogeneic transplantation will provide patients with CLL in general, and those with TP53 abnormalities in particular, with a better prognosis.

Comparative study of different methodologies to detect the JAK2 V617F mutation in chronic BCR-ABL1 negative myeloproliferative neoplasms.

OBJECTIVES: A mutation in the JAK2 gene, V617F, has been identified in several BCR-ABL1 negative myeloproliferative neoplasms (MPN): polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). Defining the presence or absence of this mutation is an essential part of clinical diagnostic algorithms and patient management. Here, we aimed to evaluate the performance of three PCR-based assays: Amplification Refractory Mutation System (ARMS), High-Resolution Melting analysis (HRM), and Sanger direct sequencing, and compare their results with those obtained by a PCR restriction fragment polymorphism assay (PCR-RFLP). DESIGN AND METHODS: We used blood samples from 136 patients (PV=20; PMF=20; ET=28, and other MPN suspected cases=68). RESULTS: Comparable results were observed among the four assays in patients with PV, PMF, and MPN suspected cases. In patients with a diagnosis of ET, the JAK2 V617F mutation was detected in 67.8% of them by the PCR-ARMS and PCR-HRM assay and in 64% of them by the conventional Sanger sequence approach. The PCR-ARMS and PCR-HRM assays were 100% concordant. With these tests, only one of the 20 patients with ET and one of the three patients with clinically suspected MPN gave different results compared with those obtained by the PCR-RFLP. CONCLUSIONS: Our results have demonstrated that the PCR-ARMS and PCR-HRM assays could detect the JAK2 V617F mutation effectively in MPN patients, but PCR-HRM assays are rapid and the most cost-effective procedures.

Pretherapeutic expression of the hOCT1 gene predicts a complete molecular response to imatinib mesylate in chronic-phase chronic myeloid leukemia.

In this retrospective study we evaluated the pretherapeutic mRNA expression of the hOCT1 (human organic cation transporter 1) gene in patients with chronic-phase (CP) chronic myeloid leukemia (CML) who varied in terms of their response to imatinib (IM). hOCT1 mRNA was quantified by real-time PCR. Patients were classified as expressing either high (n = 44) or low hOCT1 mRNA (n = 44). The complete cytogenetic response rates observed at 6, 12 and 18 months were 47.7, 84.1 and 91%, respectively, in patients with high hOCT1 mRNA and 47.5, 81.8 and 86.3%, respectively, in patients with low hOCT1 transcripts. The major molecular response rates were not significantly different between patients with high and low hOCT1 mRNA after 6 months of therapy (22.7 vs. 9.1%; p = 0.07), but they were significantly different after 12 months (54.5 vs. 31.8%; p = 0.026) and 18 months (77.2 vs. 56.8%; p = 0.034). Complete molecular responses were observed in 5 patients with low and 17 patients with high hOCT1 mRNA (p = 0.003). The 5-year event-free and overall survival analyses revealed no significant differences between the groups. These data imply that knowledge of the pretherapeutic level of hOCT1 could be a useful marker to predict IM therapy outcome in treatment-naïve CP CML patients.