Thyroid dysfunction caused by second-generation tyrosine kinase inhibitors in Philadelphia chromosome-positive chronic myeloid leukemia

BACKGROUND: Thyroid dysfunction is a well-known adverse effect of first-generation tyrosine kinase inhibitors (TKIs), like sunitinib. The aim of this study was to investigate the effect of second-generation TKIs on thyroid function. METHODS: We retrospectively assessed the effect of the first-generation TKI imatinib and the second-generation TKI nilotinib and dasatinib on thyroid function tests in 73 Philadelphia chromosome-positive (Ph-positive) chronic myeloid leukemia patients. RESULTS: Overall, 33 of 73 (45%) had one or more thyroid function test abnormalities during follow-up. Hypothyroidism or hyperthyroidism were found in 18 of 73 (25%) and 21 of 73 (29%) cases after a median of 6 and 22 weeks, respectively. In most patients (29 of 39, 74%) thyroid dysfunction was transient without clinical symptoms. Therapy of hypo-/hyperthyroidism was required in three patients. Thyroid dysfunction never resulted in the discontinuation of TKI therapy. Under treatment with imatinib, nilotinib, and dasatinib, thyroid abnormalities were detected in 25%, 55%, and 70%, respectively. Four of 55 patients (7%) treated with nilotinib had evidence for an autoimmune thyroiditis (antibody positive in 3 of 4 patients) with an episode of hyperthyroidism preceding hypothyroidism. CONCLUSIONS: Thyroid dysfunction is a common adverse event with second-generation TKI therapy in patients with Ph-positive chronic myeloid leukemia. Although the mechanism is still unclear, the high frequency of thyroid abnormalities, including autoimmune thyroiditis, warrants regular and long-term monitoring of thyroid function in these patients

Moxetumomab pasudotox in heavily pre-treated patients with relapsed/refractory hairy cell leukemia (HCL): long-term follow-up from the pivotal trial

Background: Moxetumomab pasudotox is a recombinant CD22-targeting immunotoxin. Here, we present the long-term follow-up analysis of the pivotal, multicenter, open-label trial (NCT01829711) of moxetumomab pasudotox in patients with relapsed/refractory (R/R) hairy cell leukemia (HCL). Methods: Eligible patients had received ≥ 2 prior systemic therapies, including ≥ 2 purine nucleoside analogs (PNAs), or ≥ 1 PNA followed by rituximab or a BRAF inhibitor. Patients received 40 µg/kg moxetumomab pasudotox intravenously on Days 1, 3, and 5 of each 28-day cycle for up to six cycles. Disease response and minimal residual disease (MRD) status were determined by blinded independent central review. The primary endpoint was durable complete response (CR), defined as achieving CR with hematologic remission (HR, blood counts for CR) lasting > 180 days. Results: Eighty adult patients were treated with moxetumomab pasudotox and 63% completed six cycles. Patients had received a median of three lines of prior systemic therapy; 49% were PNA-refractory, and 38% were unfit for PNA retreatment. At a median follow-up of 24.6 months, the durable CR rate (CR with HR > 180 days) was 36% (29 patients; 95% confidence interval: 26–48%); CR with HR ≥ 360 days was 33%, and overall CR was 41%. Twenty-seven complete responders (82%) were MRD-negative (34% of all patients). CR lasting ≥ 60 months was 61%, and the median progression-free survival without the loss of HR was 71.7 months. Hemolytic uremic and capillary leak syndromes were each reported in ≤ 10% of patients, and ≤ 5% had grade 3–4 events; these events were generally reversible. No treatment-related deaths were reported. Conclusions: Moxetumomab pasudotox resulted in a high rate of durable responses and MRD negativity in heavily pre-treated patients with HCL, with a manageable safety profile. Thus, it represents a new and viable treatment option for patients with R/R HCL, who currently lack adequate therapy. Trial registration: ClinicalTrials.gov identifier: NCT01829711; first submitted: April 9, 2013. https://clinicaltrials.gov/ct2/show/NCT0182971

Is there a cloud in the silver lining for imatinib?

Imatinib mesylate (Gleevec® or Glivec®), a small molecule tyrosine kinase inhibitor for the treatment of chronic myeloid leukaemia, has been said to herald the dawn of a new er-a of rationally designed, molecularly targeted oncotherapy. Lurking on the same new horizon, however, is the age-old spectre of drug resistance. This review sets the intoxicating clinical perspective against the more sobering laboratory evidence of such divergent mechanisms of imatinib resistance as gene amplification and stem cell quiescence. Polychemotherapy has already been considered to combat resistance, but a more innovative, as yet unformulated, approach may be advocated

European LeukemiaNet recommendations for the management and avoidance of adverse events of treatment in chronic myeloid leukaemia

Most reports on chronic myeloid leukaemia (CML) treatment with tyrosine kinase inhibitors (TKIs) focus on efficacy, particularly on molecular response and outcome. In contrast, adverse events (AEs) are often reported as infrequent, minor, tolerable and manageable, but they are increasingly important as therapy is potentially lifelong and multiple TKIs are available. For this reason, the European LeukemiaNet panel for CML management recommendations presents an exhaustive and critical summary of AEs emerging during CML treatment, to assist their understanding, management and prevention. There are five major conclusions. First, the main purpose of CML treatment is the antileukemic effect. Suboptimal management of AEs must not compromise this first objective. Second, most patients will have AEs, usually early, mostly mild to moderate, and which will resolve spontaneously or are easily controlled by simple means. Third, reduction or interruption of treatment must only be done if optimal management of the AE cannot be accomplished in other ways, and frequent monitoring is needed to detect resolution of the AE as early as possible. Fourth, attention must be given to comorbidities and drug interactions, and to new events unrelated to TKIs that are inevitable during such a prolonged treatment. Fifth, some TKI-related AEs have emerged which were not predicted or detected in earlier studies, maybe because of suboptimal attention to or absence from the preclinical data. Overall, imatinib has demonstrated a good long-term safety profile, though recent findings suggest underestimation of symptom severity by physicians. Second and third generation TKIs have shown higher response rates, but have been associated with unexpected problems, some of which could be irreversible. We hope these recommendations will help to minimise adverse events, and we believe that an optimal management of them will be rewarded by better TKI compliance and thus better CML outcomes, together with better quality of life.Peer reviewe

Safety and efficacy of switching to nilotinib 400 mg twice daily for patients with chronic myeloid leukemia in chronic phase with suboptimal response or failure on frontline imatinib or nilotinib 300 mg twice daily.

In a randomized, phase III trial of nilotinib versus imatinib in patients with newly diagnosed Philadelphia chromosome positive chronic myeloid leukemia in chronic phase, more patients had suboptimal response or treatment failure on front-line imatinib than on nilotinib. Patients with suboptimal response/treatment failure on imatinib 400 mg once or twice daily or nilotinib 300 mg twice daily could enter an extension study to receive nilotinib 400 mg twice daily. After a 19-month median follow up, the safety profile of nilotinib 400 mg twice daily in patients switching from imatinib (n=35) was consistent with previous reports, and few new adverse events occurred in patients escalating from nilotinib 300 mg twice daily (n=19). Of patients previously treated with imatinib or nilotinib 300 mg twice daily, respectively, 15 of 26 (58%) and 2 of 6 (33%) without complete cytogenetic response at extension study entry, and 11 of 34 (32%) and 7 of 18 (39%) without major molecular response at extension study entry, achieved these responses at any time on nilotinib 400 mg twice daily. Estimated 18-month rates of freedom from progression and overall survival after entering the extension study were lower for patients switched from imatinib (85% and 87%, respectively) versus nilotinib 300 mg twice daily (95% and 94%, respectively). Nilotinib dose escalation was generally well tolerated and improved responses in about one-third of patients with suboptimal response/treatment failure. Switch to nilotinib improved responses in some patients with suboptimal response/treatment failure on imatinib, but many did not achieve complete cytogenetic response (clinicaltrials.gov identifiers: 00718263, 00471497 - extension)

Simulation of milling cells in shell through the cam module Compas‐3D v18

У роботі проведено комп’ютерне моделювання фрезерування карманів дослідної оболонки корпусу ракетно‐космічного призначення із алюмінієвого сплаву. При моделюванні застосована програма «Модуль ЧПУ. Фрезерная обработка», що є інтегрована в систему тривимірного моделювання КОМПАС‐3D v18. Показано, що з трьох стратегій фрезерування карманів («зігзаг», «еквідистанта», «по рядках») найбільш продуктивною є стратегія «зігзаг».The computer simulation of the milling of cells of the experimental shell of the rocket space housing of aluminum alloy. For simulation, we use the program "CNC Module. Milling Processing", which is integrated into Compas‐3D v18. It is shown that of the three pocket milling strategies ("zigzag", "equidistant", "line by line") the most productive is the "zigzag" strategy

BCR-ABL1-independent PI3Kinase activation causing imatinib-resistance

<p>Abstract</p> <p>Background</p> <p>The <it>BCR-ABL1 </it>translocation occurs in chronic myeloid leukemia (CML) and in 25% of cases with acute lymphoblastic leukemia (ALL). The advent of tyrosine kinase inhibitors (TKI) has fundamentally changed the treatment of CML. However, TKI are not equally effective for treating ALL. Furthermore, <it>de novo </it>or <it>secondary </it>TKI-resistance is a significant problem in CML. We screened a panel of <it>BCR-ABL1 </it>positive ALL and CML cell lines to find models for imatinib-resistance.</p> <p>Results</p> <p>Five of 19 <it>BCR-ABL1 </it>positive cell lines were resistant to imatinib-induced apoptosis (KCL-22, MHH-TALL1, NALM-1, SD-1, SUP-B15). None of the resistant cell lines carried mutations in the kinase domain of <it>BCR-ABL1 </it>and all showed resistance to second generation TKI, nilotinib or dasatinib. STAT5, ERK1/2 and the ribosomal S6 protein (RPS6) are <it>BCR-ABL1 </it>downstream effectors, and all three proteins are dephosphorylated by imatinib in sensitive cell lines. TKI-resistant phosphorylation of RPS6, but responsiveness as regards JAK/STAT5 and ERK1/2 signalling were characteristic for resistant cell lines. PI3K pathway inhibitors effected dephosphorylation of RPS6 in imatinib-resistant cell lines suggesting that an oncogene other than <it>BCR-ABL1 </it>might be responsible for activation of the PI3K/AKT1/mTOR pathway, which would explain the TKI resistance of these cells. We show that the TKI-resistant cell line KCL-22 carries a PI3Kα E545G mutation, a site critical for the constitutive activation of the PI3K/AKT1 pathway. Apoptosis in TKI-resistant cells could be induced by inhibition of AKT1, but not of mTOR.</p> <p>Conclusion</p> <p>We introduce five Philadelphia-chromosome positive cell lines as TKI-resistance models. None of these cell lines carries mutations in the kinase domain of <it>BCR-ABL1 </it>or other molecular aberrations previously indicted in the context of imatinib-resistance. These cell lines are unique as they dephosphorylate ERK1/2 and STAT5 after treatment with imatinib, while PI3K/AKT1/mTOR activity remains unaffected. Inhibition of AKT1 leads to apoptosis in the imatinib-resistant cell lines. In conclusion, Ph+ cell lines show a form of imatinib-resistance attributable to constitutive activation of the PI3K/AKT1 pathway. Mutations in <it>PIK3CA</it>, as observed in cell line KCL-22, or PI3K activating oncogenes may undelie TKI-resistance in these cell lines.</p

The Tyrosine Kinase Inhibitor Dasatinib Induces a Marked Adipogenic Differentiation of Human Multipotent Mesenchymal Stromal Cells

BACKGROUND: The introduction of specific BCR-ABL inhibitors in chronic myelogenous leukemia therapy has entirely mutated the prognosis of this hematologic cancer from being a fatal disorder to becoming a chronic disease. Due to the probable long lasting treatment with tyrosine-kinase inhibitors (TKIs), the knowledge of their effects on normal cells is of pivotal importance. DESIGN AND METHODS: We investigated the effects of dasatinib treatment on human bone marrow-derived mesenchymal stromal cells (MSCs). RESULTS: Our findings demonstrate, for the first time, that dasatinib induces MSCs adipocytic differentiation. Particularly, when the TKI is added to the medium inducing osteogenic differentiation, a high MSCs percentage acquires adipocytic morphology and overexpresses adipocytic specific genes, including PPARγ, CEBPα, LPL and SREBP1c. Dasatinib also inhibits the activity of alkaline phosphatase, an osteogenic marker, and remarkably reduces matrix mineralization. The increase of PPARγ is also confirmed at protein level. The component of osteogenic medium required for dasatinib-induced adipogenesis is dexamethasone. Intriguingly, the increase of adipocytic markers is also observed in MSCs treated with dasatinib alone. The TKI effect is phenotype-specific, since fibroblasts do not undergo adipocytic differentiation or PPARγ increase. CONCLUSIONS: Our data demonstrate that dasatinib treatment affects bone marrow MSCs commitment and suggest that TKIs therapy might modify normal phenotypes with potential significant negative consequences