Real-world efficacy of DA-EPOCH-R/HD-MTX regimen in CD5-positive diffuse large B cell lymphoma: a single-institute analysis.

CD5-positive diffuse large B cell lymphoma (CD5+ DLBCL) is a high-risk lymphoma type. Recently, the PEARL5 (a Phase II trial of DA-EPOCH and Rituximab with HD-MTX therapy for newly diagnosed DLBCL with CD5 expression) study demonstrated the efficacy of the DA-EPOCH-R (cyclophosphamide, etoposide, doxorubicin, vincristine, prednisone, and rituximab)/HD-MTX (high-dose methotrexate) regimen for CD5+ DLBCL. In this report, we revealed the impact of the DA-EPOCH-R/HD-MTX regimen on the clinical course of CD5+ DLBCL in the real-world. We retrospectively compared CD5+ and CD5- DLBCL patients diagnosed from January 2017 to December 2020 and analyzed their clinicopathological characteristics, treatment, and prognosis. There was no difference in age, sex, clinical stage, and cell of origin; however, the CD5-positive group had higher lactate dehydrogenase levels and a worse performance status than the CD5-negative group (p=0.00121 and p=0.0378, respectively). International prognostic index (IPI) was worse in the CD5-positive group than in the CD5-negative group (p=0.0498), but NCCN-IPI (National Comprehensive Cancer Network-IPI) was no different between the two groups. The CD5-positive group was more frequently treated with the DA-EPOCH-R/HD-MTX regimen than the CD5-negative group (p =0.001857). Complete remission rate and 1-year overall survival did not differ between the CD5-positive and -negative groups (90.0% vs 81.4%, p=0.853; 81.8% vs 76.9%, p=0.433). We conclude that the DA-EPOCH-R/HD-MTX regimen is effective for CD5+ DLBCL in this single institute analysis.

Sub-lethal doses of chemotherapeutic agents induce senescence in T cells and upregulation of PD-1 expression.

Cellular senescence is a stable cell cycle arrest, usually in response to internal and/or external stress, including telomere dysfunction, abnormal cellular growth, and DNA damage. Several chemotherapeutic drugs, such as melphalan (MEL) and doxorubicin (DXR), induce cellular senescence in cancer cells. However, it is not clear whether these drugs induce senescence in immune cells. We evaluated the induction of cellular senescence in T cells were derived from human peripheral blood mononuclear cells (PBMNCs) in healthy donors using sub-lethal doses of chemotherapeutic agents. The PBMNCs were kept overnight in RPMI 1640 medium with 2% phytohemagglutinin and 10% fetal bovine serum and then cultured in RPMI 1640 with 20 ng/mL IL-2 and sub-lethal doses of chemotherapeutic drugs (2 µM MEL and 50 nM DXR) for 48 h. Sub-lethal doses of chemotherapeutic agents induced phenotypes associated with senescence, such as the formation of γH2AX nuclear foci, cell proliferation arrest, and induction of senescence-associated beta-galactosidase (SA-ß-Gal) activity, (control vs. MEL, DXR; median mean fluorescence intensity (MFI) 1883 (1130-2163) vs. 2233 (1385-2254), 2406.5 (1377-3119), respectively) in T cells. IL6 and SPP1 mRNA, which are senescence-associated secretory phenotype (SASP) factors, were significantly upregulated by sublethal doses of MEL and DXR compared to the control (P = 0.043 and 0.018, respectively). Moreover, sub-lethal doses of chemotherapeutic agents significantly enhanced the expression of programmed death 1 (PD-1) on CD3 + CD4 + and CD3 + CD8 + T cells compared to the control (CD4 + T cells; P = 0.043, 0.043, and 0.043, respectively, CD8 + T cells; P = 0.043, 0.043, and 0.043, respectively). Our results suggest that sub-lethal doses of chemotherapeutic agents induce senescence in T cells and tumor immunosuppression by upregulating PD-1 expression on T cells.

Myeloma Microenvironmental TIMP1 Induces the Invasive Phenotype in Fibroblasts to Modulate Disease Progression.

Tissue inhibitors of metalloproteinases (TIMPs) are endogenous matrix metalloproteinase inhibitors. TIMP1 is produced by cancer cells and has pleiotropic activities. However, its role and source in multiple myeloma (MM) are unclear. Here, we evaluated TIMP1 protein and mRNA levels in bone marrow (BM) plasma cells and assessed the effects of TIMP1 expression on fibroblast invasive capacity using three-dimensional spheroid cell invasion assays. TIMP1 mRNA and protein levels were elevated when patients progressed from monoclonal gammopathy of undetermined significance or smouldering myeloma to MM. Furthermore, TIMP1 levels decreased at complete response and TIMP1 protein levels increased with higher international staging. TIMP1 mRNA levels were markedly higher in extramedullary plasmacytoma and MM with t(4;14). Overall survival and post-progression survival were significantly lower in MM patients with high TIMP1 protein. Recombinant TIMP1 did not directly affect MM cells but enhanced the invasive capacity of fibroblasts; this effect was suppressed by treatment with anti-TIMP1 antibodies. Fibroblasts supported myeloma cell invasion and expansion in extracellular matrix. Overall, these results suggested that MM-derived TIMP1 induces the invasive phenotype in fibroblasts and is involved in disease progression. Further studies are required to elucidate the specific roles of TIMP1 in MM and facilitate the development of novel therapies targeting the TIMP1 pathway.

MYC Causes Multiple Myeloma Progression via Attenuating TP53-Induced MicroRNA-34 Expression.

MicroRNAs (miRNAs and miRs) are small (19-25 base pairs) non-coding RNAs with the ability to modulate gene expression. Previously, we showed that the miR-34 family is downregulated in multiple myeloma (MM) as the cancer progressed. In this study, we aimed to clarify the mechanism of miRNA dysregulation in MM. We focused particularly on the interaction between MYC and the TP53-miR34 axis because there is a discrepancy between increased TP53 and decreased miR-34 expressions in MM. Using the nutlin-3 or Tet-on systems, we caused wild-type (WT) p53 protein accumulation in human MM cell lines (HMCLs) and observed upregulated miR-34 expression. Next, we found that treatment with an Myc inhibitor alone did not affect miR-34 expression levels, but when it was coupled with p53 accumulation, miR-34 expression increased. In contrast, forced MYC activation by the MYC-ER system reduced nutlin-3-induced miR-34 expression. We also observed that TP53 and MYC were negatively correlated with mature miR-34 expressions in the plasma cells of patients with MM. Our results suggest that MYC participates in the suppression of p53-dependent miRNA expressions. Because miRNA expression suppresses tumors, its inhibition leads to MM development and malignant transformation.

IgG4-related Disease with a Cardiac Mass.

A 69-year-old man with palpitations and decreased blood pressure was referred. Echocardiography showed a mass in the right atrium and cardiac septum. The serum IgG4 level was 1,450 mg/dL. A biopsy of the cardiac mass showed fibrosis with inflammatory cells and increased IgG4-positive plasma cells and lymphocytes. Flow cytometry and polymerase chain reaction of the immunoglobulin heavy chain did not demonstrate monoclonality. He was diagnosed with IgG4-related disease (IgG4-RD). IgG4-RD with a cardiac mass is rare and it is difficult to distinguish it from malignant lymphoma by a pathological examination alone. We therefore performed a biopsy and analyzed the clonality in order to make an accurate diagnosis of IgG4-RD.

[Giant hemophilic pseudotumors in brothers with non-severe hemophilia B].

Hemophilic pseudotumors can occur in patients with hemophilia because of recurrent bleeding and poor hemostasis. A man in his 30s with hemophilia B and human immunodeficiency virus/hepatitis C virus co-infection complicated by liver cirrhosis presented with a large pseudotumor in the left iliopsoas muscle. However, resting to stop bleeding was difficult with his daily work. Osteolytic changes in the left ilium progressed over 8 years. A large osteolytic pseudotumor in the pelvis was also incidentally identified in his younger brother during his 30s. The same mutations in F9 (p. Arg294Gln, hemizygous mutation) associated with a non-severe phenotype were detected in both brothers. The clinical courses of the brothers suggested that large pseudotumors can occur in patients with non-severe hemophilia and underline the importance of patient education.

Longitudinal nosocomial outbreak of Pseudomonas fluorescens bloodstream infection of 2 years' duration in a coronary care unit.

BACKGROUND: Outbreaks of bloodstream infections (BSI) of nonfermenting bacteria are a critical issue and often associated with hospital environments. We experienced a long-lasting outbreak of Pseudomonas fluorescens BSI limited to a coronary care unit (CCU). METHODS: We conducted a retrospective epidemiologic investigation and a case-control study for Pseudomonas fluorescens BSI from April 2011-July 2014. Environmental sample culture was conducted to detect the specific environmental source of transmission. RESULTS: Hospital-wide microbiology data from the term identified 13 case patients with P fluorescens BSI and 32 control patients with BSI due to organisms other than P fluorescens in the CCU. The case-control study revealed that the case group had significantly higher odds of exposure to only cardiac output (CO) measurement with thermodilution method (odds ratio, 22.0; 95% confidence interval, 2.4-202.3). The organism was identified only from an ice bath used for CO measurement. The susceptibility patterns were identical among all strains derived from the cases and the environment. CONCLUSIONS: The nosocomial outbreak of P fluorescens BSI in our CCU over 2 years was associated with a contaminated ice bath used for CO measurement within the unit. Detection and elimination of the specific source was essential to stop the outbreak.