Initial Efficacy of the COVID-19 mRNA Vaccine Booster and Subsequent Breakthrough Omicron Variant Infection in Patients with B-Cell Non-Hodgkin's Lymphoma: A Single-Center Cohort Study.

It has been suggested that the effect of coronavirus disease 2019 (COVID-19) booster vaccination in patients with B-cell non-Hodgkin's lymphoma (B-NHL) is inferior to that in healthy individuals. However, differences according to histological subtype or treatment status are unclear. In addition, there has been less research on patients who subsequently develop breakthrough infections. We investigated the effects of the first COVID-19 booster vaccination for patients with B-NHL and the clinical features of breakthrough infections in the Omicron variant era. In this study, B-NHL was classified into two histological subtypes: aggressive lymphoma and indolent lymphoma. Next, patients were subdivided according to treatment with anticancer drugs at the start of the first vaccination. We also examined the clinical characteristics and outcomes of patients who had breakthrough infections after a booster vaccination. The booster effect of the COVID-19 mRNA vaccine in patients with B-NHL varied considerably depending on treatment status at the initial vaccination. In the patient group at more than 1 year after the last anticancer drug treatment, regardless of the histological subtype, the booster effect was comparable to that in the healthy control group. In contrast, the booster effect was significantly poorer in the other patient groups. However, of the 213 patients who received the booster vaccine, 22 patients (10.3%) were infected with COVID-19, and 18 patients (81.8%) had mild disease; these cases included the patients who remained seronegative. Thus, we believe that booster vaccinations may help in reducing the severity of Omicron variant COVID-19 infection in patients with B-NHL.

Helicobacter pylori eradication treatment for primary gastric diffuse large B-cell lymphoma: A single-center analysis.

BACKGROUND: Unlike the already established effect of Helicobacter pylori (H. pylori) eradication on gastric mucosa-associated lymphoid tissue (MALT) lymphoma, its therapeutic effect on primary gastric diffuse large B-cell lymphoma (DLBCL) is still unclear. AIM: To clarify the efficacy of H. pylori eradication treatment for primary gastric DLBCL. METHODS: We reported on 3 new cases, and added them to 3 previously reported cases. We analyzed the usefulness of H. pylori eradication treatment for gastric DLBCL for a total of 6 cases at our center. RESULTS: Of the 6 patients (27-90 years old, 3 males and 3 females), all 3 patients with single lesions (one transformed from MALT lymphoma) achieved complete remission (CR) after H. pylori eradication. Regarding the 2 newly reported cases, CR was maintained for more than 6 years with eradication treatment alone. In contrast, none of the 3 patients with 2 lesions achieved CR. In 1 newly reported case, endoscopic CR was achieved in one lesion, while stable disease was obtained in the other lesion. Two patients with progressive disease responded to standard chemotherapy ± radiation and remained in CR for more than 6 years. CONCLUSION: We believe it is worthwhile to attempt H. pylori eradication for elderly patients with primary gastric DLBCL in a single lesion with a small tumor burden.

Successful bridging therapy with tirabrutinib before ASCT for relapsed primary DLBCL of the CNS complicated with PBC, cirrhosis, and pancytopenia.

The optimal therapy for relapsed primary diffuse large B-cell lymphoma (DLBCL) of the central nervous system (CNS) remains unclear. We herein report a case of relapsed primary DLBCL of the CNS complicated with primary biliary cholangitis, cirrhosis, and pancytopenia that was successfully treated with bridging therapy with tirabrutinib before autologous hematopoietic stem cell transplantation (ASCT). Tirabrutinib is well tolerated and effective for relapsed primary DLBCL of the CNS with comorbidities, including cirrhosis and pancytopenia. Tirabrutinib is a promising option as bridging therapy before ASCT.

Imaging findings of a case of intravascular large B-cell lymphoma with cardiac involvement.

Intravascular large B-cell lymphoma (IVLBCL) is a very rare subtype of malignant lymphoma that is difficult to diagnose. Cases of myocardial infarction caused by IVLBCL are even rarer. Herein, we report a case presenting with heart failure and delayed enhancement in the hypokinetic cardiac septum on contrast-enhanced cardiac magnetic resonance imaging. Myocardial biopsy showed large B-cell lymphoma cells in the microvessels within the myocardium. To the best of our knowledge, this is the first report of imaging findings of cardiac involvement in IVLBCL.

[Successful treatment of myelomatous pleural effusion with daratumumab administration before autologous peripheral stem cell transplantation].

A 50-year-old woman diagnosed with surgically resected plasmacytoma of the ovaries and uterus presented with another plasmacytoma in the pancreas with positive uptake on positron emission tomography (PET) and massive right pleural effusion with plasma cell infiltration (myelomatous pleural effusion). After four courses of the bortezomib, lenalidomide, and dexamethasone regimen as induction therapy, partial response was achieved with reduced myelomatous pleural effusion and negative uptake on PET in the pancreatic plasmacytoma. However, soon after she received bortezomib and high-dose cyclophosphamide for peripheral blood stem cell harvesting, right myelomatous pleural effusion increased without signs of heart failure or infection. Because of the progressive nature of the disease, daratumumab was introduced as 2 courses of daratumumab, lenalidomide, and dexamethasone (DLd) regimen, after which she achieved complete response with disappearance of the pleural effusion. After autologous peripheral blood stem cell transplantation, she received an additional four courses of the DLd regimen as consolidation therapy. She maintained relapse-free survival for two years with maintenance therapy containing daratumumab and dose-reduced lenalidomide. Our case may suggest the usefulness of daratumumab before autologous peripheral stem cell transplantation for relapsed/refractory myelomatous pleural effusion.

DPP8 is a novel therapeutic target for multiple myeloma.

Dipeptidyl peptidases (DPPs) are proteolytic enzymes that are ideal therapeutic targets in human diseases. Indeed, DPP4 inhibitors are widely used in clinical practice as anti-diabetic agents. In this paper, we show that DPP4 inhibitors also induced cell death in multiple human myeloma cells. Among five DPP4 inhibitors, only two of them, vildagliptin and saxagliptin, exhibited apparent cytotoxic effects on myeloma cell lines, without any difference in suppression of DPP4 activity. As these two DPP4 inhibitors are known to have off-target effects against DPP8/9, we employed the specific DPP8/9 inhibitor 1G244. 1G244 demonstrated anti-myeloma effects on several cell lines and CD138+ cells from patients as well as in murine xenograft model. Through siRNA silencing approach, we further confirmed that DPP8 but not DPP9 is a key molecule in inducing cell death induced by DPP8/9 inhibition. In fact, the expression of DPP8 in CD38+ cells from myeloma patients was higher than that of healthy volunteers. DPP8/9 inhibition induced apoptosis, as evidenced by activated form of PARP, caspases-3 and was suppressed by the pan-caspase inhibitor Z-VAD-FMK. Taken together, these results indicate that DPP8 is a novel therapeutic target for myeloma treatment.

The Novel Pathogenesis of Retinopathy Mediated by Multiple RTK Signals is Uncovered in Newly Developed Mouse Model.

Pericyte desorption from retinal blood vessels and subsequent vascular abnormalities are the pathogenesis of diabetic retinopathy (DR). Although the involvement of abnormal signals including platelet-derived growth factor receptor-ß (PDGFRß) and vascular endothelial growth factor-A (VEGF-A) have been hypothesized in DR, the mechanisms that underlie this processes are largely unknown. Here, novel retinopathy mouse model (N-PRß-KO) was developed with conditional Pdgfrb gene deletion by Nestin promoter-driven Cre recombinase (Nestin-Cre) that consistently reproduced through early non-proliferative to late proliferative DR pathologies. Depletion of Nestin-Cre-sensitive PDGFRß+NG2+αSMA- pericytes suppressed pericyte-coverages and induced severe vascular lesion and hemorrhage. Nestin-Cre-insensitive PDGFRß+NG2+αSMA+ pericytes detached from the vascular wall, and subsequently changed into myofibroblasts in proliferative membrane to cause retinal traction. PDGFRα+ astrogliosis was seen in degenerated retina. Expressions of placental growth factor (PlGF), VEGF-A and PDGF-BB were significantly increased in the retina of N-PRß-KO. PDGF-BB may contribute to the pericyte-fibroblast transition and glial scar formation. Since VEGFR1 signal blockade significantly ameliorated the vascular phenotype in N-PRß-KO mice, the augmented VEGFR1 signal by PlGF and VEGF-A was indicated to mediate vascular lesions. In addition to PDGF-BB, PlGF and VEGF-A with their intracellular signals may be the relevant therapeutic targets to protect eyes from DR.