Dasatinib suppresses atherosclerotic lesions by suppressing cholesterol uptake in a mouse model of hypercholesterolemia.

Although the use of BCR-ABL1 tyrosine kinase inhibitors (TKIs) for chronic myeloid leukemia is known to cause vascular adverse events (VAEs), the frequency of VAEs during dasatinib administration is not high, and the same holds for atherosclerosis-related VAEs. However, its effect on atherosclerosis remains controversial. In this study, our primary objective was to investigate how dasatinib affects atherosclerosis. Ldlr-/-/Apobec1-/- mice, which are highly prone to develop atherosclerosis, were administered dasatinib. After 16 weeks, we evaluated their atherosclerotic lesions. We used bone-marrow-derived macrophages to investigate the uptake of oxidized low-density lipoprotein (LDL) complexed with DiI dye (DiI-oxLDL). RNA sequencing and quantitative reverse transcription polymerase chain reaction (RT-qPCR) were performed to explore the potential effects of dasatinib on cholesterol metabolism. Dasatinib administration significantly reduced atherosclerotic lesions (P < 0.001 and P = 0.013) and DiI-oxLDL uptake (P < 0.001) unlike other TKIs. RNA sequencing and RT-qPCR suggested that Sort1, which encodes sortilin, a known regulator of LDL uptake, and Cd36 were potential targets of dasatinib. In conclusion, dasatinib induced elevated LDL-C levels, but oxLDL uptake in macrophages were suppressed, resulting in reducing atherosclerotic lesions. These results further our understanding of the differences in VAEs between dasatinib and other TKIs.

[Sarcoidosis-lymphoma syndrome showing abnormal FDG uptake in lymph nodes and muscles upon post-chemotherapy PET/CT imaging].

A 65-year-old woman was diagnosed with rheumatoid arthritis in 2010 and was treated with methotrexate (MTX). In 2012, she was diagnosed with sarcoidosis and underwent a follow-up therapy for mild peripheral neuropathy due to neurosarcoidosis. In 2018, she experienced primary splenic diffuse large B-cell lymphoma (DLBCL) and was diagnosed with sarcoidosis-lymphoma syndrome (SLS). MTX was discontinued, and six cycles of rituximab were administered combined with chemotherapy. Positron emission tomography combined with computed tomography performed 18 weeks after the last cycle of chemotherapy showed new abnormal fluoro-2-deoxy-D-glucose (FDG) uptake in the mediastinal and hilar lymph nodes and skeletal muscles. Sarcoidosis was suspected because of increased serum angiotensin-converting enzyme levels and magnetic resonance imaging findings in the lower limb muscles. However, pathological findings of DLBCL and sarcoidosis were not confirmed in the hilar lymph node biopsy. Therefore, malignant lymphoma can be distinguished from sarcoidosis using abnormal FDG uptake after chemotherapy for SLS.

Successful treatment with nilotinib after bosutinib-induced pulmonary arterial hypertension recurrence following dasatinib in chronic myeloid leukemia in chronic phase.

A 52-year-old man was diagnosed with chronic myeloid leukemia in the chronic phase (CML-CP). He experienced bosutinib-induced pulmonary arterial hypertension (PAH) recurrence following dasatinib use. Symptoms and examination findings associated with PAH improved after bosutinib cessation. Although nilotinib was started because of the loss of response after bosutinib cessation, a deep molecular response without PAH recurrence was achieved 3 months after the initiation of nilotinib therapy. PAH recurrence after switching to bosutinib due to dasatinib-induced PAH should be closely monitored. In addition, nilotinib therapy might be an effective approach in PAH cases related to dasatinib and/or bosutinib in patients with CML-CP.

Prognostic impact of the dosage of methotrexate combined with tacrolimus for graft-versus-host disease prophylaxis after cord blood transplantation.

The optimal dosage of methotrexate (MTX) for graft-versus-host disease (GVHD) prophylaxis after cord blood transplantation (CBT) has not been well elucidated. Therefore, we conducted a retrospective study comparing a mini-MTX group (5 mg/m2 on day 1, 3 and 6) to a short-MTX group (10 mg/m2 on day 1 and 7 mg/m2 on day 3 and 6) after CBT. Sixty-three patients were classified as the mini-MTX group and 20 as the short-MTX group. The median time and cumulative incidence of neutrophil engraftment did not vary between the two groups. The cumulative incidence of grade 2-4 and grade 3-4 acute GVHD was similar in both groups. Overall survival in the mini-MTX group was significantly lower than in the short-MTX group (46.9% vs. 88.7% at 1 year, p < 0.01), contributing to higher non-relapse mortality (NRM) in the mini-MTX group (32.0% vs. 5.0% at 1 year, p = 0.02). In multivariate analysis, the mini-MTX regimen was the most powerful prognostic factor for OS (hazard ratio 4.11; p = 0.03). Although the reduced dosage of MTX had no effect on neutrophil engraftment, increased NRM due to higher incidence of infection, graft failure, and severe acute GVHD resulted in a lower survival rate in the mini-MTX group after CBT.

Simple isotope dilution headspace-GC-MS analysis of naphthalene and p-dichlorobenzene in whole blood and urine.

A very simple and sensitive method for the simultaneous analysis of naphthalene and p-dichlorobenzene in human whole blood and urine by headspace capillary gas chromatography-mass spectrometry (GC-MS) is presented. The advantages of the method were that as much as 1 mL of headspace vapor could be injected into a GC port in the splitless mode, and that the addition of deuterated naphthalene and p-dichlorobenzene as internal standards resulted in much better headspace extraction efficiencies, which resulted in high sensitivity. The detection limits for both naphthalene and p-dichlorobenzene were 1 ng mL(-1) for whole blood and 0.5 ng mL(-1) for urine. Validation data, such as the linearity of calibration curves, reproducibility and recovery rates, were all satisfactory. Using this method, both compounds could actually be detected from whole blood samples of a male volunteer after the inhalation of each gas of the compounds.