Dasatinib induces endothelial dysfunction leading to impaired recovery from ischaemia.

Chronic myeloid leukaemia (CML) management is complicated by treatment-emergent vascular adverse events seen with tyrosine kinase inhibitors (TKIs) such as nilotinib, dasatinib and ponatinib. Pleural effusion and pulmonary arterial hypertension (PAH) have been associated with dasatinib treatment. Endothelial dysfunction and impaired angiogenesis are hallmarks of PAH. In this study, we explored, at cellular and whole animal levels, the connection between dasatinib exposure and disruption of endothelial barrier integrity and function, leading to impaired angiogenesis. Understanding the mechanisms whereby dasatinib initiates PAH will provide opportunities for intervention and prevention of such adverse effects, and for future development of safer TKIs, thereby improving CML management.

Gilteritinib with or without venetoclax for relapsed/refractory FLT3-mutated acute myeloid leukaemia.

Patients with FLT3-mutated acute myeloid leukaemia (AML) that relapse or are refractory (R/R) to intensive induction have poor outcomes. Gilteritinib has recently become standard-of-care for patients with R/R FLT3-mutated AML. We investigated whether adding venetoclax to gilteritinib (gilt-ven) improves outcomes as compared with gilteritinib monotherapy. We included patients treated with gilteritinib (n = 19) and gilt-ven (n = 17) for R/R AML after intensive chemotherapy. Gilteritinib and gilt-ven groups did not differ in terms of mCRc rates (53% and 65%, p = 0.51) and realization of allogeneic haematopoietic stem-cell transplantation (HSCT, 47% and 35%, p = 0.5). Overall survival (OS) was comparable between groups, although a trend towards better OS was seen with gilt-ven (12-month OS 58.8% [95% CI 39.5%-87.6%]) versus gilteritinib (42.1% [95% CI 24.9%-71.3%] for gilteritinib). Early salvage with gilt-ven versus any other gilteritinib-based approach was associated with the best outcome (p = 0.031). Combination therapy was associated with increased haematological toxicity. In summary, gilt-ven did not improve remissions or HSCT-realization rates in patients with R/R FLT3-mutated AML as compared with gilteritinib and was associated with increased haematological toxicity. Although OS did not differ, a trend towards better survival was suggested with gilt-ven and a survival benefit was shown for gilt-ven approach when sequenced early for salvage.

CML in the very elderly: the impact of comorbidities and TKI selection in a real-life multicenter study.

Tyrosine kinase inhibitors (TKIs) have greatly improved chronic myeloid leukemia (CML) treatments, with survival rates close to the general population. Yet, for the very elderly, robust data remains limited. This study focused on assessing comorbidities, treatment approaches, responses, and survival for elderly CML patients. Our study was conducted on 123 elderly (≥ 75 years) CML patients across four centers in Israel and Moffitt Cancer Center, USA. The median age at diagnosis was 79.1 years, with 44.7% being octogenarians. Comorbidities were very common; cardiovascular risk factors (60%), cardiovascular diseases (42%), with a median age-adjusted Charlson Comorbidity Index (aaCCI) of 5. Imatinib was the leading first-line therapy (69%), while the use of second-generation TKIs increased post-2010. Most patients achieved a major molecular response (MMR, 66.7%), and half achieved a deep molecular response (DMR, 50.4%). Over half (52.8%) of patients moved to second-line, and nearly a quarter (23.5%) to third-line treatments, primarily due to intolerance. Overall survival (OS) was notably longer in patients with an aaCCI score below 5, and in patients who attained DMR. Contrary to expectations, the Israeli cohort showed a shorter actual life expectancy than projected, suggesting a larger impact of CML on elderly survival. In summary, imatinib remains the main initial treatment, but second-generation TKIs are on the rise among elderly CML patients. Outcomes in elderly CML patients depend on comorbidities, TKI type, response, and age, underscoring the need for personalized therapy and additional research on TKI effectiveness and safety.

Utility of echocardiogram in neutropenic patients with gram positive bacteremia - a retrospective study.

INTRODUCTION: Hemato-oncology patients are vulnerable to bloodstream infections due to immunocompromised state and use of intravascular catheters. Data regarding risk of infective endocarditis (IE) among those with gram positive bacteremia is limited. We aimed to evaluate the incidence of IE among neutropenic hemato-oncology patients, and to explore the yield of echocardiogram in this population. METHODS: we conducted a single retrospective study of all hospitalized hemato-oncology neutropenic patients with gram positive blood cultures between 2007 and 2021. Data regarding Patients' characteristics, blood cultures and echocardiogram was collected. RESULTS: Study included 241 patients, with 283 isolates. Coagulase negative staphylococcus (CONS) were the most commonly isolates found, followed by streptococcus viridans. Trans thoracic echocardiography (TTE) was performed in 45% of patients overall, of which 5.8% had additional Trans esophageal echocardiogram (TEE). Only a single case of IE was identified; 47 y/o multiple myeloma patient with neutropenic fever, streptococcus viridans bacteremia, and stroke caused by septic emboli. TTE and TEE failed to demonstrate valvular pathology consistent with IE. Conclusion In our experience, the yield of echocardiogram in hemato-oncological neutropenic patients with bacteremia is extremely low, owing to reduced probability of IE in this population, and thus could be avoided in most cases.

Anticoagulation in cancer patients with atrial fibrillation and grade 3-4 thrombocytopenia.

INTRODUCTION: Atrial fibrillation or flutter (AF) is prevalent in cancer patients. Many of these patients have an indication for anticoagulation (AC) but are also at risk for developing chemotherapy-induced thrombocytopenia. There are scarce data regarding management of AC and risk of bleeding and thrombosis in cancer patients with AF and thrombocytopenia. AIM: To assess anticoagulation management and incidence of bleeding and arterial thromboembolism (ATE) in cancer patients with AF and grade 3-4 thrombocytopenia (platelets <50 × 109/L). METHODS: A retrospective cohort study included adults with active cancer, grade 3-4 thrombocytopenia and AF with CHA2DS2-VASc score ≥ 1. Patients were stratified according to AC discontinuation (No-AC) or continuation (Continue-AC) when platelets dropped below 50 × 109/L and followed for 30 days. The study outcomes were ATE (ischemic stroke, transient ischemic attack or systemic emboli) and major bleeding. Cox proportional hazards model was used to calculate hazard ratios (HR) with death as a competing risk (Fine and Gray model). RESULTS: The cohort included 131 patients; 90 in the No-AC group and 41 in the Continue-AC group. Patient characteristics were balanced between the groups. The 30-day cumulative incidence of ATE was 2 % [95 % CI 0.4 %-7 %] in the No-AC group and 2 % [0.2 %-11 %] in the Continue-AC group (HR 0.92 [95 % CI 0.09-9.88]). The 30-day cumulative incidence of major bleeding was 7.8 % [95 % CI 3.40 %-14.52 %] and 2.44 % [95 % CI 0.18 %-11.22 %] in the No-AC and Continue-AC groups, respectively (HR 3.29 [95 % CI 0.42-26.04]). CONCLUSIONS: The high rate of bleeding and low rate of ATE in thrombocytopenic cancer patients with AF suggests that holding AC during time-limited periods may be a reasonable approach.

Lymphoplasmacytic lymphoma and multiple myeloma coexisting in the same patient: a case series and literature review.

The simultaneous occurrence of Waldenström macroglobulinemia and multiple myeloma in the same patient has been published as case reports. Patients with Waldenström macroglobulinemia often have a small clone of plasma cells. However, the concurrent occurrence of symptomatic myeloma with lytic bone lesions is rare. The diagnosis of this 'hybrid' entity is challenging, and there are no standard therapies. We present six patients from five centers (three in Israel and two in the United States). We describe these patients' unique clinical course and treatment approaches.

Chronic Lymphocytic Leukemia (CLL)-Derived Extracellular Vesicles Educate Endothelial Cells to Become IL-6-Producing, CLL-Supportive Cells.

We hypothesized that via extracellular vesicles (EVs), chronic lymphocytic leukemia (CLL) cells turn endothelial cells into CLL-supportive cells. To test this, we treated vein-derived (HUVECs) and artery-derived (HAOECs) endothelial cells with EVs isolated from the peripheral blood of 45 treatment-naïve patients. Endothelial cells took up CLL-EVs in a dose- and time-dependent manner. To test whether CLL-EVs turn endothelial cells into IL-6-producing cells, we exposed them to CLL-EVs and found a 50% increase in IL-6 levels. Subsequently, we filtered out the endothelial cells and added CLL cells to this IL-6-enriched medium. After 15 min, STAT3 became phosphorylated, and there was a 40% decrease in apoptosis rate, indicating that IL-6 activated the STAT3-dependent anti-apoptotic pathway. Phospho-proteomics analysis of CLL-EV-exposed endothelial cells revealed 23 phospho-proteins that were upregulated, and network analysis unraveled the central role of phospho-ß-catenin. We transfected HUVECs with a ß-catenin-containing plasmid and found by ELISA a 30% increase in the levels of IL-6 in the culture medium. By chromatin immunoprecipitation assay, we observed an increased binding of three transcription factors to the IL-6 promoter. Importantly, patients with CLL possess significantly higher levels of peripheral blood IL-6 compared to normal individuals, suggesting that the inducers of endothelial IL-6 are the neoplastic EVs derived from the CLL cells versus those of healthy people. Taken together, we found that CLL cells communicate with endothelial cells through EVs that they release. Once they are taken up by endothelial cells, they turn them into IL-6-producing cells.

Is serum-derived exosomal hTERT transcript a marker of oncogenic activity in primary brain tumors? An exploratory study.

BACKGROUND: In order to proliferate indefinitely, all tumors require a telomere maintenance mechanism. The expression of human telomerase reverse transcriptase (hTERT) enables telomere maintenance and provides cancer cells with limitless replicative potential. As such, it may serve as an attractive biomarker for oncogenic activity. This study explored whether a liquid biopsy that analyses blood derived exosomal hTERT transcript (e-hTERT-trans) may serve as such a biomarker in gliomas and meningiomas when compared to healthy controls. METHODS: Exosomes were isolated from the pre-operative sera of patients' samples stored in the biobank of both Rabin and Sheba Medical Centers. The levels of e-hTERT-trans were measured in 81 healthy controls, 117 meningiomas, 17 low-grade gliomas, and 61 glioblastomas. Clinical parameters of the patients were collected retrospectively and compared to the levels of the e-hTERT-trans. RESULTS: The upper normal limit of controls e-hTERT-trans was 1.85 relative quantitation (RQ). The rate of detection increased with rising tumor grade and correlated with tumor recurrence in meningiomas: mean RQ without recurrence (2.17 ± 11.7) versus with recurrence (3.59 ± 4.42; p = 0.002). In glioblastomas, preoperative measurements correlated with tumor volume and with the disease course on serial sampling. CONCLUSIONS: We demonstrated for the first time that the expression of e-hTERT-trans transcript can be measured in the serum of primary brain tumors. This exosomal marker carries the potential to serve as a biomarker once used in conjunction with other clinical and radiological parameters. Future studies are required to investigate whether the sensitivity could be augmented and whether it can be implemented into routine patients care.