Kinetics of BCR::ABL1 transcript levels and molecular relapse after tyrosine kinase inhibitors discontinuation in chronic myeloid leukemia patients: preliminary results from the DES-CML study.

Tyrosine kinase inhibitors (TKI) have revolutionized the treatment of patients with chronic myeloid leukemia. Patients who achieve sustained deep molecular response are eligible for treatment discontinuation. DES-CML is an ongoing, phase 2 multicentric discontinuation trial. Adult patients with CML in chronic phase with typical BCR::ABL1 transcripts, stable deep molecular response (MR4.5 IS) for two years, and no previous resistance were eligible. Patients underwent a phase of TKI dose de-escalation for six months before discontinuation. TKI was reintroduced at the previous dose if the patient lost major molecular response (MMR) at any time. This study aimed to assess the impact of BCR-ABL transcript kinetics during TKI de-escalation and discontinuation phases on treatment-free survival. So far, the study recruited 41 patients, and 38 patients discontinued therapy (4 were in the second discontinuation attempt). Eleven patients lost MMR, one during the de-escalation phase and ten after discontinuation. 24-month treatment-free survival was 66% (95% CI: 48-84%) in a median follow-up of 7 (1-30) months. No patient lost hematological response or had disease progression. A higher rate of molecular relapses occurred in patients with fluctuating BCR::ABL1 levels after the discontinuation phase (with loss of MR4.5, but no loss of MMR) (P=0.04, HR-4.86 (1.03-22.9) but not confirmed in the multivariate analysis. The longer duration of TKI treatment (P=0.03, HR-1.02, 95%CI - 1.00-1.04) and MMR (P=0.004, HR-0.95, 95%CI - 0.92-098) were independent factors of a lower relapse rate.

Bioactive Lipids as Chronic Myeloid Leukemia's Potential Biomarkers for Disease Progression and Response to Tyrosine Kinase Inhibitors.

Chronic myelogenous leukemia (CML) is a myeloproliferative neoplasm that expresses the Philadelphia chromosome and constitutively activated Bcr-Abl tyrosine kinase in hematopoietic progenitor cells. Bcr-Abl tyrosine-kinase inhibitors (TKI) do not definitively cure all CML patients. The efficacy of TKI is reduced in CML patients in the blastic phase-the most severe phase of the disease-and resistance to this drug has emerged. There is limited knowledge on the underlying mechanisms of disease progression and resistance to TKI beyond BCR-ABL1, as well as on the impact of TKI treatment and disease progression on the metabolome of CML patients. The present study reports the metabolomic profiles of CML patients at different phases of the disease treated with TKI. The plasma metabolites from CML patients were analyzed using liquid chromatography, mass spectrometry, and bioinformatics. Distinct metabolic patterns were identified for CML patients at different phases of the disease and for those who were resistant to TKI. The lipid metabolism in CML patients at advanced phases and TKI-resistant patients is reprogrammed, as detected by analysis of metabolomic data. CML patients who were responsive and resistant to TKI therapy exhibited distinct enriched pathways. In addition, ceramide levels were higher and sphingomyelin levels were lower in resistant patients compared with control and CML groups. Taken together, the results here reported established metabolic profiles of CML patients who progressed to advanced phases of the disease and failed to respond to TKI therapy as well as patients in remission. In the future, an expanded study on CML metabolomics may provide new potential prognostic markers for disease progression and response to therapy.

Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular Consensus on genetically modified cells. III: anti-CD19 CAR-T cell therapy for patients with non-Hodgkin lymphoma.

The treatment and evolution of B-cell non-Hodgkin lymphoma (B-NHL) has undergone important changes in the last years with the emergence of targeted therapies, such as monoclonal antibodies, small molecules, antibody-drug conjugates, and bispecific antibodies. Nevertheless, a significant portion of patients remains refractory or relapsed (R/R) to the new therapeutic modalities, representing thus an unmet medical need. The use of CAR-T cells for the treatment of B-NHL patients has shown to be a promising therapy with impressive results in patients with R/R disease. The expectations are as high as the imminent approval of CAR-T cell therapy in Brazil, which it is expected to impact the prognosis of R/R B-NHL. The aim of this manuscript is to offer a consensus of specialists in the field of onco-hematology and cellular therapy, working in Brazil and United States, in order to discuss and offer recommendations in the present setting of the use of CAR-T cells for patients with B-NHL.

Clinical and molecular profile of a Brazilian cohort of patients with classical BCR-ABL1-negative myeloproliferative neoplasms

ABSTRACT Background: The classical BCR-ABL1-negative myeloproliferative neoplasms (MPNs) are Polycythemia Vera (PV), Essential Thrombocythemia (ET) and Primary Myelofibrosis (PMF). In developing countries, there are few reports that truly reveal the clinical setting of these patients. Therefore, we aimed to characterize a single center MPN population with a special focus on the correct diagnosis based on the recent review of the WHO criteria for the diagnosis of myeloid neoplasms. Methods: This retrospective study analyzed data from medical records of patients with classical BCR-ABL1-negative MPNs diagnosed from January 1997 to October 2017 and followed at the University Hospital of Ribeirão Preto Medical School. Results: A total of 162 patients were assessed, 61 with PV, 50 with ET, and 51 with PMF. The mutational status analysis revealed that 113 (69.3%) harbored the JAK2V617F mutation, 23 (14.1%), the CALR mutation, and 12 (7.4%) had a triple-negative status. None of the patients were found to have mutations on the thrombopoietin receptor gene (MPL), including some ET and PMF patients who were not tested. Among the PV patients, 57 (93.5%) were positive for the JAK2V617F mutation, one (1.6%) presented an in-frame deletion JAK2 exon 12 mutation and one (1.6%) presented a missense JAK2 exon 9 mutation, not previously described. The overall survival was lower in the triple-negative patients with PMF, when compared to the JAK2V617F or CALR-mutated (p= 0.002). Conclusion: The frequency of somatic mutations and survival in our cohort, stratified according to the respective disease, was consistent with the literature data, despite some limitations. Further prospective epidemiological studies of MPN cohorts are encouraged in developing countries.

Clinical and molecular profile of a Brazilian cohort of patients with classical BCR-ABL1-negative myeloproliferative neoplasms.

BACKGROUND: The classical BCR-ABL1-negative myeloproliferative neoplasms (MPNs) are Polycythemia Vera (PV), Essential Thrombocythemia (ET) and Primary Myelofibrosis (PMF). In developing countries, there are few reports that truly reveal the clinical setting of these patients. Therefore, we aimed to characterize a single center MPN population with a special focus on the correct diagnosis based on the recent review of the WHO criteria for the diagnosis of myeloid neoplasms. METHODS: This retrospective study analyzed data from medical records of patients with classical BCR-ABL1-negative MPNs diagnosed from January 1997 to October 2017 and followed at the University Hospital of Ribeirão Preto Medical School. RESULTS: A total of 162 patients were assessed, 61 with PV, 50 with ET, and 51 with PMF. The mutational status analysis revealed that 113 (69.3%) harbored the JAK2V617F mutation, 23 (14.1%), the CALR mutation, and 12 (7.4%) had a triple-negative status. None of the patients were found to have mutations on the thrombopoietin receptor gene (MPL), including some ET and PMF patients who were not tested. Among the PV patients, 57 (93.5%) were positive for the JAK2V617F mutation, one (1.6%) presented an in-frame deletion JAK2 exon 12 mutation and one (1.6%) presented a missense JAK2 exon 9 mutation, not previously described. The overall survival was lower in the triple-negative patients with PMF, when compared to the JAK2V617F or CALR-mutated (p = 0.002). CONCLUSION: The frequency of somatic mutations and survival in our cohort, stratified according to the respective disease, was consistent with the literature data, despite some limitations. Further prospective epidemiological studies of MPN cohorts are encouraged in developing countries.

Expression of Hippo signaling pathway and Aurora kinase genes in chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm resulting from clonal expansion of hematopoietic stem cells positive for the Philadelphia chromosome. The CML pathogenesis is associated with expression of the BCR-ABL1 oncogene, which encodes the Bcr-Abl protein with tyrosine kinase activity, promoting the leukemic cell exacerbated myeloproliferation and resistance to apoptosis. CML patients are usually treated with tyrosine kinase inhibitors (TKI), but some of them acquire resistance or are refractory to TKI. Thus, it is still relevant to elucidate the CML pathogenesis and seek new therapeutic targets, such as the Hippo signaling pathway and cell cycle regulatory genes from the Aurora kinase family. The present study quantified the expression level of genes encoding components of the Hippo signaling pathway (LATS1, LATS2, YAP, and TAZ), AURKA and AURKB in CML patients at different stages of the disease, who were resistant or sensitive to imatinib mesylate therapy, and in healthy individuals. The expression levels of the target genes were correlated with the CML Sokal's prognostic score. The most striking results were the LATS2 and AURKA overexpression in CML patients, the overexpression of TAZ and AURKB in CML patients at advanced phases and TAZ in CML IM-resistant. The development of drugs and/or identification of tumor markers for the Hippo signaling pathway and the Aurora kinase family, either alone or in combination, can optimize CML treatment by enhancing the susceptibility of leukemic cells to apoptosis and leading to a better disease prognosis.