Effect of IL-2 polymorphism rs2069762 on single-unit cord blood transplant outcomes.

BACKGROUND: Interleukin-2 (IL-2) is one of the most important cytokines that regulate the activation and proliferation of T cells and natural killer cells. The production of IL-2 may be affected by polymorphisms in the promoter region of the IL-2 gene (rs2069762). In allogeneic hematopoietic cell transplantation (HCT) from adult donors, rs2069762 has been associated with the incidence of acute and chronic graft-versus-host disease (GVHD). However, the impacts of IL-2 polymorphism on cord blood transplantation (CBT) outcomes remain unclear. OBJECTIVE: The objective of this study was to assess the impact of IL-2 polymorphism rs2069762 on transplant outcomes, such as hematopoietic recovery, GVHD, overall survival, relapse, and non-relapse mortality (NRM) after CBT. STUDY DESIGN: We conducted a retrospective analysis of data from adult patients who underwent single-unit CBT at our institution from November 2005 to March 2023 for whom DNA samples from recipients and donors were available. IL-2 genotyping was performed using real-time polymerase chain reaction with the TaqMan® SNP genotyping assay for rs2069762. RESULTS: A total of 143 recipient and donor pairs were included in this study. The proportion of recipient IL-2 polymorphism rs2069762 was 48 % (n = 69) for AA, 42 % (n = 60) for CA, and 10 % (n = 14) for CC. The proportion of donor IL-2 polymorphism rs2069762 was 43 % (n = 61) for AA, 48 % (n = 69) for CA, and 9 % (n = 13) for CC. In the multivariate analysis, the use of an rs2069762 CA + CC donor was associated with lower neutrophil recovery compared to an rs2069762 AA donor (hazard ratio [HR], 0.66; 95 % confidence interval [CI], 0.50-0.88; P = 0.004). Furthermore, recipients of rs2069762 CA + CC were associated with higher NRM compared to recipients of rs2069762 AA (HR, 2.32; 95 % CI, 1.01-5.34; P = 0.047). Serum IL-2 levels at 8 weeks were significantly higher in rs2069762 CA + CC recipients compared to those with rs2069762 AA recipients (P = 0.014). CONCLUSION: Our data showed that donor IL-2 polymorphism affects neutrophil recovery and recipient IL-2 polymorphism affects NRM in adults undergoing single-unit CBT. The polymorphism of IL-2 rs2069762 in recipients and donors might be associated with the clinical outcomes of single-unit CBT.

Analyzing factors affecting positivity in drive-through COVID-19 testing: a cross-sectional study.

BACKGROUND: Demand for COVID-19 testing prompted the implementation of drive-through testing systems. However, limited research has examined factors influencing testing positivity in this setting. METHODS: From October 2020 to March 2023, a total of 1,341 patients, along with their clinical information, were referred from local clinics to the Sasebo City COVID-19 drive-through PCR center for testing. Association between clinical information or factors related to the drive-through center and testing results was analyzed by Fisher's exact test and logistic regression models. RESULTS: Individuals testing positive exhibited higher frequencies of upper respiratory symptoms; cough (OR 1.5 (95% CI 1.2-1.8), p < 0.001, q = 0.005), sore throat (OR 2.4 (95% CI 1.9-3.0), p < 0.001, q < 0.001), runny nose (OR 1.4 (95% CI 1.1-1.8), p = 0.002, q = 0.009), and systemic symptoms; fever (OR 1.5 (95% CI 1.1-2.0), p = 0.006, q = 0.02), headache (OR 1.9 (95% CI 1.4-2.5), p < 0.001, q < 0.001), and joint pain (OR 2.7 (95% CI 1.8-4.1), p < 0.001, q < 0.001). Conversely, gastrointestinal symptoms; diarrhea (OR 0.2 (95% CI 0.1-0.4), p < 0.001, q < 0.001) and nausea (OR 0.3 (95% CI 0.1-0.6), p < 0.001, q < 0.001) were less prevalent among positives. During omicron strain predominant period, higher testing positivity rate (OR 20 (95% CI 13-31), p < 0.001) and shorter period from symptom onset to testing (3.2 vs. 6.0 days, p < 0.001) were observed compared to pre-omicron period. Besides symptoms, contact history with infected persons at home (OR 4.5 (95% CI 3.1-6.5), p < 0.001, q < 0.001) and in office or school (OR 2.9 (95% CI 2.1-4.1), p < 0.001, q < 0.001), as well as the number of sample collection experiences by collectors (B 7.2 (95% CI 2.8-12), p = 0.002) were also associated with testing results. CONCLUSIONS: These findings underscore the importance of factors related to drive-through centers, especially contact history interviews and sample collection skills, for achieving higher rates of COVID-19 testing positivity. They also contribute to enhanced preparedness for next infectious disease pandemics.

[Durable remission of T-cell prolymphocytic leukemia with CLEC16A::IL2 after allogeneic hematopoietic stem cell transplantation].

A 64-year-old woman presented with fine motor impairment in both hands. MRI revealed a contrast-enhanced lesion in the medulla oblongata. Lymphoid cells with abnormal blebs were observed and a CD4+/CD8+ double positive (DP) T cell population was detected by flow cytometry (FCM) in the bone marrow (BM) and the peripheral blood (PB). CLEC16A::IL2 fusion gene was identified by whole exome sequencing with DNA prepared from DP T cells. Clonal rearrangement of the T-cell receptor gene and expression of TCL1A protein were detected. This led to a diagnosis of T-cell prolymphocytic leukemia (T-PLL) with central nervous system (CNS) infiltration. Abnormal cells in BM and PB became undetectable on microscopy and FCM, and the CNS lesion disappeared on MRI after second-line therapy with alemtuzumab. Meanwhile, the CLEC16A::IL2 fusion mRNA remained detectable in PB. Allogeneic hematopoietic stem-cell transplantation was performed, and the fusion mRNA has now been undetectable for more than 5 years since transplantation. This is the first report of a T-PLL case with a CLEC16A::IL2 fusion gene.

Clinical and prognostic features of Langerhans cell histiocytosis in adults.

Langerhans cell histiocytosis (LCH) is a rare disease characterized by clonal expansion of CD1a+ CD207+ myeloid dendritic cells. The features of LCH are mainly described in children and remain poorly defined in adults; therefore, we conducted a nationwide survey to collect clinical data from 148 adult patients with LCH. The median age at diagnosis was 46.5 (range: 20-87) years with male predominance (60.8%). Among the 86 patients with detailed treatment information, 40 (46.5%) had single system LCH, whereas 46 (53.5%) had multisystem LCH. Moreover, 19 patients (22.1%) had an additional malignancy. BRAF V600E in plasma cell-free DNA was associated with a low overall survival (OS) rate and the risk of the pituitary gland and central nervous system involvement. At a median follow-up of 55 months from diagnosis, six patients (7.0%) had died, and the four patients with LCH-related death did not respond to initial chemotherapy. The OS probability at 5 years post-diagnosis was 90.6% (95% confidence interval: 79.8-95.8). Multivariate analysis showed that patients aged ≥60 years at diagnosis had a relatively poor prognosis. The probability of event-free survival at 5 years was 52.1% (95% confidence interval: 36.6-65.5), with 57 patients requiring chemotherapy. In this study, we first revealed the high rate of relapse after chemotherapy and mortality of poor responders in adults as well as children. Therefore, prospective therapeutic studies of adults with LCH using targeted therapies are needed to improve outcomes in adults with LCH.

Genetic analysis of low-grade adenosquamous carcinoma of the breast progressing to high-grade metaplastic carcinoma.

PURPOSE: Low-grade adenosquamous carcinoma (LGASC) is a rare type of metaplastic carcinoma of the breast (MBC) with an indolent clinical course. A few LGASC cases with high-grade transformation have been reported; however, the genetics underlying malignant progression of LGASC remain unclear. METHODS: We performed whole-genome sequencing analysis on five MBCs from four patients, including one case with matching primary LGASC and a lymph node metastatic tumor consisting of high-grade MBC with a predominant metaplastic squamous cell carcinoma component (MSC) that progressed from LGASC and three cases of independent de novo MSC. RESULTS: Unlike de novo MSC, LGASC and its associated MSC showed no TP53 mutation and tended to contain fewer structural variants than de novo MSC. Both LGASC and its associated MSC harbored the common GNAS c.C2530T:p.Arg844Cys mutation, which was more frequently detected in the cancer cell fraction of MSC. MSC associated with LGASC showed additional pathogenic deletions of multiple tumor-suppressor genes, such as KMT2D and BTG1. Copy number analysis revealed potential 18q loss of heterozygosity in both LGASC and associated MSC. The frequency of SMAD4::DCC fusion due to deletions increased with progression to MSC; however, chimeric proteins were not detected. SMAD4 protein expression was already decreased at the LGASC stage due to unknown mechanisms. CONCLUSION: Not only LGASC but also its associated high-grade MBC may be genetically different from de novo high-grade MBC. Progression from LGASC to high-grade MBC may involve the concentration of driver mutations caused by clonal selection and inactivation of tumor-suppressor genes.

[The efficacy of alemtuzumab for pure red cell aplasia associated with autoimmune polyendocrine syndrome type 1].

We present a case of a 41-year-old woman who was diagnosed with autoimmune polyendocrine syndrome type 1 (APS-1) at the age of 2. She developed severe anemia and was diagnosed with pure red cell aplasia (PRCA) and T-cell large granular lymphocyte leukemia at the age of 34. The pathogenesis of APS-1 is based on the presence of an inactive mutation in the autoimmune regulator gene on thymic medullary epithelial cells. It is thought that the autoimmune T cells generated by impaired negative selection in the thymus induce PRCA. The patient was treated with immunosuppressive therapy (ciclosporin, antithymocyte globulin, prednisolone, and cyclophosphamide) for a long time by her previous doctor. After a long period of remission and exacerbation, she became dependent on blood transfusion approximately at the age of 40 and was transferred to our hospital. At our hospital, alemtuzumab treatment resulted in the disappearance of large granular lymphocytes and improvement of anemia. We report this case as a valuable demonstration of the efficacy of alemtuzumab for treating PRCA associated with APS-1.

Controlled Tetradeuteration of Straight-Chain Fatty Acids: Synthesis, Application, and Insight into the Metabolism of Oxidized Linoleic Acid.

We describe a concise and reliable protocol for the precisely controlled tetradeuteration of straight-chain fatty acids (FAs) at the α- and ß-positions that is generally applicable to a variety of FAs, including trans-FAs, polyunsaturated FAs (PUFAs), and their oxidized derivatives. The precisely controlled introduction of four deuterium atoms into the FAs enables their persistent and quantitative tracking by LC-MS/MS analysis based on their molecular structures. In addition, the phosphatidylcholine (PC) species prepared from the tetradeuterated FAs thus obtained give a diagnostic peak, namely, a phosphocholine fragment that contains deuterium, in the LC-MS/MS analysis. With these features, the metabolism of a representative oxidized linoleic acid, that is, hydroxyoctadecadienoic acid (HODE), was investigated, leading to the identification of acyltransferases that transfer the acyl moiety derived from HODE to lysophosphatidylcholine.

Prognostic impact of circulating tumor DNA status post-allogeneic hematopoietic stem cell transplantation in AML and MDS.

This study was performed to assess the utility of tumor-derived fragmentary DNA, or circulating tumor DNA (ctDNA), for identifying high-risk patients for relapse of acute myeloid leukemia and myelodysplastic syndrome (AML/MDS) after undergoing myeloablative allogeneic hematopoietic stem cell transplantation (alloSCT). We retrospectively collected tumor and available matched serum samples at diagnosis and 1 and 3 months post-alloSCT from 53 patients with AML/MDS. After identifying driver mutations in 51 patients using next-generation sequencing, we designed at least 1 personalized digital polymerase chain reaction assay per case. Diagnostic ctDNA and matched tumor DNA exhibited excellent correlations with variant allele frequencies. Sixteen patients relapsed after a median of 7 months post-alloSCT. Both mutation persistence (MP) in bone marrow (BM) at 1 and 3 months post-alloSCT and corresponding ctDNA persistence (CP) in the matched serum (MP1 and MP3; CP1 and CP3, respectively) were comparably associated with higher 3-year cumulative incidence of relapse (CIR) rates (MP1 vs non-MP1, 72.9% vs 13.8% [P = .0012]; CP1 vs non-CP1, 65.6% vs 9.0% [P = .0002]; MP3 vs non-MP3, 80% vs 11.6% [P = .0002]; CP3 vs non-CP3, 71.4% vs 8.4% [P < .0001]). We subsequently evaluated whether subset analysis of patients with 3 genes associated with clonal hematopoiesis, DNMT3A, TET2, and ASXL1 (DTA), could also be helpful in relapse prediction. As a result, CP based on DTA gene mutations also had the prognostic effect on CIR. These results, for the first time, support the utility of ctDNA as a noninvasive prognostic biomarker in patients with AML/MDS undergoing alloSCT.

Circulating cell-free DNA in the peripheral blood plasma of patients is an informative biomarker for multiple myeloma relapse.

BACKGROUND: Multiple myeloma (MM) is an incurable hematological malignancy. Despite the introduction of several novel drugs, most patients relapse. Biomarkers to identify the early signs of relapse will make it possible to adjust the therapeutic strategy before the disease worsens. Although understanding genetic changes is important for the treatment of MM, currently known biomarkers of relapse, including serum free-light chains and monoclonal paraproteins, are not associated with genetic changes. METHODS: We therefore performed a multicenter study to examine the usefulness of circulating cell-free DNA (cfDNA) present in the peripheral blood (PB) plasma of patients as a biomarker for MM relapse. RESULTS: We identified several driver mutations by combined analysis of next-generation sequencing and existing databases of candidate oncogenes. Furthermore, relapse was detected more sensitively by monitoring the circulating cfDNA with these driver mutations than by conventional serum free-light chain examination. CONCLUSION: These results suggest the potential utility of cfDNA in the PB plasma of patients as a relevant early biomarker for MM relapse.

Glycosphingolipids with Very Long-Chain Fatty Acids Accumulate in Fibroblasts from Adrenoleukodystrophy Patients.

Adrenoleukodystrophy (X-ALD) is an X-linked genetic disorder caused by mutation of the ATP-binding cassette subfamily D member 1 gene, which encodes the peroxisomal membrane protein, adrenoleukodystrophy protein (ALDP). ALDP is associated with the transport of very-long-chain fatty acids (VLCFAs; carbon chain length ≥ 24) into peroxisomes. Defective ALDP leads to the accumulation of saturated VLCFAs in plasma and tissues, which results in damage to myelin and the adrenal glands. Here, we profiled the glycosphingolipid (GSL) species in fibroblasts from X-ALD patients. Quantitative analysis was performed using liquid chromatography-electrospray ionization-tandem mass spectrometry with a chiral column in multiple reaction monitoring (MRM) mode. MRM transitions were designed to scan for precursor ions of long-chain bases to detect GSLs, neutral loss of hexose to detect hexosylceramide (HexCer), and precursor ions of phosphorylcholine to detect sphingomyelin (SM). Our results reveal that levels of C25 and C26-containing HexCer, Hex2Cer, NeuAc-Hex2Cer, NeuAc-HexNAc-Hex2Cer, Hex3Cer, HexNAc-Hex3Cer, and SM were elevated in fibroblasts from X-ALD patients. In conclusion, we precisely quantified SM and various GSLs in fibroblasts from X-ALD patients and determined structural information of the elevated VLCFA-containing GSLs.

[Prognostic impact of circulating tumor DNA status post-allogeneic hematopoietic stem cell transplantation in acute myeloid leukemia and myelodysplastic syndromes].

Relapse is an issue of concern for patients with acute myeloid leukemia and myelodysplastic syndromes (AML/MDS) who underwent allogeneic hematopoietic stem cell transplantation (allo HSCT). The conventional minimal residual disease (MRD) test of the bone marrow has serious limitations regarding invasiveness and applicability. To address this problem, we investigated the utility of a novel MRD test using tumor-derived fragmentary DNA, or circulating tumor DNA (ctDNA) for the identification of patients with high risk of AML/MDS relapse after undergoing myeloablative allo HSCT. We retrospectively collected tumor specimens and available matched serum samples at diagnosis and at 1 and 3 months post-allo HSCT from 53 patients with AML/MDS. After identifying driver mutations in 51 patients using next-generation sequencing, we designed at least one personalized digital polymerase chain reaction assay per case. Diagnostic ctDNA and matched tumor DNA exhibited excellent correlations with variant allele frequencies. Sixteen patients relapsed after a median of 7 months post allo HSCT. Both the mutation persistence in the bone marrow at 1 and 3 months post allo HSCT and the corresponding ctDNA persistence in the matched serum were comparably associated with higher 3-year cumulative incidence of relapse rates. These results demonstrate, for the first time, the utility of ctDNA as a noninvasive prognostic biomarker in patients with AML/MDS who underwent allo HSCT.

[Cooccurrence of classic Hodgkin lymphoma and multiple myeloma].

Although classic Hodgkin's lymphoma (CHL) sometimes develops after treatment for multiple myeloma (MM), simultaneous diagnosis of both malignancies is extremely rare without previous treatment history. Here we describe a case of a 54-year-old female who complained of left cervical lymphadenopathy. Biopsy specimen from the left cervical lymph node revealed mixed-cellularity CHL. Bone marrow aspirate comprised 10.3% plasma cells. She was diagnosed with MM due to involved: uninvolved serum free light chain ratio of >100. She achieved complete response for CHL after 4 cycles of doxorubicin, bleomycin, vinblastine, and dacarbazine chemotherapy along with 30 Gy of involved-field radiotherapy. Three years later, bortezomib, lenalidomide, and dexamethasone (VRd-lite) therapy was initiated for MM. Severe neutropenia during her 1st cycle prompted a dosage reduction of lenalidomide and bortezomib. Partial response was achieved after 4 cycles of VRd-lite followed by high-dose melphalan/autologous stem cell transplantation. No severe adverse events were recorded. This was followed by 4 cycles of carfilzomib, lenalidomide, and dexamethasone therapy, which resulted in complete remission. As the number of elderly people increases, multiple myeloma patients with previous history of other malignancies would increase. Our case has shown that VRd-lite therapy may be suitable for those patients.

Hexacosenoyl-CoA is the most abundant very long-chain acyl-CoA in ATP binding cassette transporter D1-deficient cells.

X-linked adrenoleukodystrophy (X-ALD) is an inherited disorder caused by deleterious mutations in the ABCD1 gene. The ABCD1 protein transports very long-chain FAs (VLCFAs) from the cytosol into the peroxisome where the VLCFAs are degraded through ß-oxidation. ABCD1 dysfunction leads to VLCFA accumulation in individuals with X-ALD. FAs are activated by esterification to CoA before metabolic utilization. However, the intracellular pools and metabolic profiles of individual acyl-CoA esters have not been fully analyzed. In this study, we profiled the acyl-CoA species in fibroblasts from X-ALD patients and in ABCD1-deficient HeLa cells. We found that hexacosenoyl (26:1)-CoA, but not hexacosanoyl (26:0)-CoA, was the most abundantly concentrated among the VLCFA-CoA species in these cells. We also show that 26:1-CoA is mainly synthesized from oleoyl-CoA, and the metabolic turnover rate of 26:1-CoA was almost identical to that of oleoyl-CoA in both WT and ABCD1-deficient HeLa cells. The findings of our study provide precise quantitative and metabolic information of each acyl-CoA species in living cells. Our results suggest that VLCFA is endogenously synthesized as VLCFA-CoA through a FA elongation pathway and is then efficiently converted to other metabolites, such as phospholipids, in the absence of ABCD1.

Role of exosomes as a proinflammatory mediator in the development of EBV-associated lymphoma.

Epstein-Barr virus (EBV) causes various diseases in the elderly, including B-cell lymphoma such as Hodgkin's lymphoma and diffuse large B-cell lymphoma. Here, we show that EBV acts in trans on noninfected macrophages in the tumor through exosome secretion and augments the development of lymphomas. In a humanized mouse model, the different formation of lymphoproliferative disease (LPD) between 2 EBV strains (Akata and B95-8) was evident. Furthermore, injection of Akata-derived exosomes affected LPD severity, possibly through the regulation of macrophage phenotype in vivo. Exosomes collected from Akata-lymphoblastoid cell lines reportedly contain EBV-derived noncoding RNAs such as BamHI fragment A rightward transcript (BART) micro-RNAs (miRNAs) and EBV-encoded RNA. We focused on the exosome-mediated delivery of BART miRNAs. In vitro, BART miRNAs could induce the immune regulatory phenotype in macrophages characterized by the gene expressions of interleukin 10, tumor necrosis factor-α, and arginase 1, suggesting the immune regulatory role of BART miRNAs. The expression level of an EBV-encoded miRNA was strongly linked to the clinical outcomes in elderly patients with diffuse large B-cell lymphoma. These results implicate BART miRNAs as 1 of the factors regulating the severity of lymphoproliferative disease and as a diagnostic marker for EBV+ B-cell lymphoma.

High Prevalence of Left Ventricular Non-Compaction and Its Effect on Chemotherapy-Related Cardiac Dysfunction in Patients With Hematological Diseases.

BACKGROUND: Recent progress in chemotherapy has prolonged the survival of patients with hematological diseases, but has also increased the number of patients with chemotherapy-related cardiac dysfunction (CTRCD). However, the causes of individual variations and risk factors for CTRCD have yet to be fully elucidated.Methods and Results:Consecutive echocardiograms of 371 patients were retrospectively evaluated for the presence of left ventricular (LV) non-compaction (LVNC). Individual LV ejection fraction (LVEF) outcome estimates were made using bivariate linear regression with log-transformed duration Akaike information criterion (AIC) model fitting. The prevalence of LVNC was 6-fold higher in patients with hematological diseases than in those with non-hematological diseases (12% vs. 2%; risk ratio 6.1; 95% confidence interval [CI] 2.0, 18.2). Among patients with hematological diseases, the ratio of myeloid diseases was significantly higher in the group with LVNC (P=0.031). Deterioration of LVEF was more severe in patients with than without LVNC (-14.4 percentage points/year [95% CI -21.0, -7.9] vs. -4.6 percentage points/year [95% CI -6.8, -2.4], respectively), even after multivariate adjustment for baseline LVEF, background disease distributions, cumulative anthracycline dose, and other baseline factors. CONCLUSIONS: LVNC is relatively prevalent in patients with hematological diseases (particularly myeloid diseases) and can be one of the major risk factors for CTRCD. Detailed cardiac evaluations including LVNC are recommended for patients undergoing chemotherapy.

[Artificial intelligence-guided precision medicine in hematological disorders].

Precision medicine in oncology uses genomic data to provide the right intervention in the right patients at the right time. For this purpose, next-generation sequencing (NGS) is an indispensable tool. However, further innovations are necessary, including medical informatics which uses somatic mutations to inform clinical intervention. This process, called manual interpretation or curation, is currently labor-intensive, involving experienced curators who identify the relevant evidence among a growing body of knowledge and translate it into medical practice. To address this issue, since 2015, we have been organizing a clinical sequencing (CS) team, which integrates clinical and genomic information related to hematological malignancies with the aid of artificial intelligence (AI). So far, we have collated AI-assisted CS data for more than 300 patients with hematological cancers. In this paper, we provide a brief introduction for the nonspecialist to the manual interpretation process together with an overview of a representative AI platform, Watson for Genomics. Based on our own experience, we highlight why AI is needed in the manual interpretation process in CS. We also present some of the pitfalls and limitations of AI that hematologists should be aware of when interpreting AI-output.

Complex formation of sphingomyelin synthase 1 with glucosylceramide synthase increases sphingomyelin and decreases glucosylceramide levels.

Sphingolipids, including sphingomyelin (SM) and glucosylceramide (GlcCer), are generated by the addition of a polar head group to ceramide (Cer). Sphingomyelin synthase 1 (SMS1) and glucosylceramide synthase (GCS) are key enzymes that catalyze the conversion of Cer to SM and GlcCer, respectively. GlcCer synthesis has been postulated to occur mainly in cis-Golgi, and SM synthesis is thought to occur in medial/trans-Golgi; however, SMS1 and GCS are known to partially co-localize in cisternae, especially in medial/trans-Golgi. Here, we report that SMS1 and GCS can form a heteromeric complex, in which the N terminus of SMS1 and the C terminus of GCS are in close proximity. Deletion of the N-terminal sterile α-motif of SMS1 reduced the stability of the SMS1-GCS complex, resulting in a significant reduction in SM synthesis in vivo In contrast, chemical-induced heterodimerization augmented SMS1 activity, depending on an increase in the amount and stability of the complex. Fusion of the SMS1 N terminus to the GCS C terminus via linkers of different lengths increased SM synthesis and decreased GlcCer synthesis in vivo These results suggest that formation of the SMS1-GCS heteromeric complex increases SM synthesis and decreases GlcCer synthesis. Importantly, this regulation of relative Cer levels by the SMS1-GCS complex was confirmed by CRISPR/Cas9-mediated knockout of SMS1 or GCS combined with pharmacological inhibition of Cer transport protein in HEK293T cells. Our findings suggest that complex formation between SMS1 and GCS is part of a critical mechanism controlling the metabolic fate of Cer in the Golgi.

Acyl Chain Preference in Foam Cell Formation from Mouse Peritoneal Macrophages.

Macrophage foam cells play critical roles in the initiation and development of atherosclerosis by synthesizing and accumulating cholesteryl ester (CE) in lipid droplets. However, in analyzing lipid metabolism in foam cell formation, studies have focused on the sterol group, and little research has been done on the acyl chains. Therefore, we adapted a model system using liposomes containing particular acyl chains and examined the effect of various acyl chains on foam cell formation. Of the phosphatidylserine (PS) liposomes tested containing PS, phosphatidylcholine, and cholesterol, we found that unsaturated (C18:1), but not saturated (C16:0 and C18:0), PS liposomes induced lipid droplet formation, indicating that foam cell formation depends on the nature of the acyl chain of the PS liposomes. Experiments on the uptake and accumulation of cholesterol from liposomes by adding [14C]cholesterol suggested that foam cell formation could be induced only when cholesterol was converted to CE in the case of C18:1 PS liposomes. Both microscopic observations and metabolic analysis suggest that cholesterol incorporated into either C16:0 or C18:0 PS liposomes may stay intact after being taken in by endosomes. The [14C]C18:1 fatty acyl chain in the C18:1 PS liposome was used to synthesize CE and triacylglycerol (TG). Interestingly, the [14C]C16:0 in the C18:1 PS liposome was metabolized to sphingomyelin rather than being incorporated into either CE or TG, which could be because of enzymatic acyl chain selectivity. In conclusion, our results indicate that the acyl chain preference of macrophages could have some impact on their progression to foam cells.

Splenic marginal zone lymphoma complicated by cold agglutinin disease.

Splenic marginal zone lymphoma (SMZL) is a rare low-grade B-cell lymphoma accounting for less than 1% of lymphoid neoplasms and is often associated with autoimmune disorders. A 48-year-old woman presented with severe anemia due to steroid-refractory cold agglutinin disease (CAD), and was referred to our hospital for management of progressive systemic illness and high fever. On admission, she showed elevated serum soluble IL-2R and mild splenomegaly. PET/CT revealed FDG accumulation in the spleen and bone. She was pathologically diagnosed as having splenic marginal zone lymphoma by splenectomy and received 8 cycles of rituximab every 2 weeks, resulting in marked improvement of anemia. Lymphoma cells were positive for CD20/CD11c/CD13, phenotypically compatible with SMZL. We report herein the characteristic features of SMZL, and appropriate procedures for diagnosis and treatment.

[Autologous peripheral blood stem cell transplantation for double-refractory myeloma with K-RAS and N-RAS mutations].

The prognosis of multiple myeloma (MM) has been improved due to the introduction of novel agents like proteasome inhibitors and immunomodulatory drugs (IMiDs). However, some cases are refractory to the use of novel agents, and the prognosis of such cases is poor. A 53-year-old male was diagnosed with MM and categorized as follows: Bence-Jones protein lambda type MM, Durie-Salmon IIIA, international staging system (ISS) stage II, and revised ISS stage II. Mutations in K-RAS and IGH/FGFR3 translocation were detected at diagnosis. His tumor was refractory to seven therapeutic regimens including bortezomib, IMiDs (lenalidomide, thalidomide, pomalidomide), conventional chemotherapy, and radiation therapy. N-RAS mutations, CKS1B gains, and C-MYC split signals were detected after treatment. We performed high-dose melphalan/autologous stem cell transplantation (HD-MEL/ASCT) as a salvage therapy and achieved very good partial response. The correlation between K-RAS mutations and poor prognosis or between N-RAS mutations and reduced sensitivity to bortezomib is reported. However, RAS mutations are reported as a favorable factor for HD-MEL/ASCT. In general, mutations of both the K-RAS and N-RAS are known to be mutually exclusive. This rare MM case has mutations in both K-RAS and N-RAS, and the possible relevance of these mutations to both the refractoriness to novel therapies and sensitivity to HD-MEL/ASCT is suggested.