Chihiro Yamamoto

Rituximab plus 70% cyclophosphamide, doxorubicin, vincristine and prednisone for Japanese patients with diffuse large B-cell lymphoma aged 70 years and older

Abstract In the rituximab era, several large studies have suggested that full-dose rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) might be the best treatment for patients with diffuse large B-cell lymphoma (DLBCL) aged 60 years and older. However, it remains unclear whether this is also the case for those aged 70 years and older. Previously untreated patients with DLBCL aged 70 years and older (elderly) were treated with R-70%CHOP, and patients younger than 70 years (younger) were treated with full-dose R-CHOP every 3 weeks, for a total of 6–8 cycles. Complete remission (CR) rates in elderly versus younger patients were 75 vs. 78% (p = 0.7), respectively. The 3-year overall survival, event-free survival and progression-free survival of elderly versus younger patients were 58 vs. 78% (p < 0.05), 45 vs. 70% (p < 0.05) and 64 vs. 72% (p = 0.43), respectively. Severe adverse events were more frequent in the elderly, even with the dose reduction in that age group. Three-year PFS with R-70%CHOP for patients aged 70 years and older was not significantly worse than that with full-dose R-CHOP for younger patients, suggesting that R-70% CHOP might be a reasonable choice for patients with DLBCL aged 70 years and older, especially for those with comorbidities.

The Tol2 transposon system mediates the genetic engineering of T-cells with CD19-specific chimeric antigen receptors for B-cell malignancies

Engineered T-cell therapy using a CD19-specific chimeric antigen receptor (CD19-CAR) is a promising strategy for the treatment of advanced B-cell malignancies. Gene transfer of CARs to T-cells has widely relied on retroviral vectors, but transposon-based gene transfer has recently emerged as a suitable nonviral method to mediate stable transgene expression. The advantages of transposon vectors compared with viral vectors include their simplicity and cost-effectiveness. We used the Tol2 transposon system to stably transfer CD19-CAR into human T-cells. Normal human peripheral blood lymphocytes were co-nucleofected with the Tol2 transposon donor plasmid carrying CD19-CAR and the transposase expression plasmid and were selectively propagated on NIH3T3 cells expressing human CD19. Expanded CD3+ T-cells with stable and high-level transgene expression (~95%) produced interferon-γ upon stimulation with CD19 and specifically lysed Raji cells, a CD19+ human B-cell lymphoma cell line. Adoptive transfer of these T-cells suppressed tumor progression in Raji tumor-bearing Rag2−/−γc−/− immunodeficient mice compared with control mice. These results demonstrate that the Tol2 transposon system could be used to express CD19-CAR in genetically engineered T-cells for the treatment of refractory B-cell malignancies.

CD19 target-engineered T-cells accumulate at tumor lesions in human B-cell lymphoma xenograft mouse models.

Adoptive T-cell therapy with CD19-specific chimeric antigen receptors (CARs) is promising for treatment of advanced B-cell malignancies. Tumor targeting of CAR-modified T-cells is likely to contribute therapeutic potency; therefore we examined the relationship between the ability of CD19-specific CAR (CD19-CAR)-transduced T-cells to accumulate at CD19(+) tumor lesions, and their ability to provide anti-tumor effects in xenograft mouse models. Normal human peripheral blood lymphocytes, activated with immobilized RetroNectin and anti-CD3 antibodies, were transduced with retroviral vectors that encode CD19-CAR. Expanded CD19-CAR T-cells with a high transgene expression level of about 75% produced IL-2 and IFN-γ in response to CD19, and lysed both Raji and Daudi CD19(+) human B-cell lymphoma cell lines. Furthermore, these cells efficiently accumulated at Raji tumor lesions where they suppressed tumor progression and prolonged survival in tumor-bearing Rag2(-/-)γc(-/-) immunodeficient mice compared to control cohorts. These results show that the ability of CD19-CAR T-cells to home in on tumor lesions is pivotal for their anti-tumor effects in our xenograft models, and therefore may enhance the efficacy of adoptive T-cell therapy for refractory B-cell lymphoma.

Clinical outcomes of myeloid/lymphoid neoplasms with fibroblast growth factor receptor-1 (FGFR1) rearrangement

ABSTRACT Objective: Myeloid/lymphoid neoplasms with fibroblast growth factor receptor-1 (FGFR1) rearrangement are hematopoietic stem cell disorders with a poor prognosis, but no established standard therapy. Methods: We experienced a patient with T-lymphoblastic lymphoma (LBL) associated with FGFR1 rearrangement who underwent cord blood transplantation, but died of pulmonary complication. We collected the clinical data of patients with FGFR1 rearrangement from the medical literature and analyzed 45 patients, including our patient. Results: The primary diagnoses were myeloproliferative neoplasm (MPN) or myelodysplastic syndromes (MDS) in 14 and acute leukemia or LBL in 31. In MPN and MDS patients, the cumulative incidence of transformation to blast phase (BP) at 12 months was 46.2%. The 1-year overall survival (OS) from diagnosis in all cases was 43.1%. With regard to the impact of treatment response on survival, the achievement of complete response with a landmark at 2 months after diagnosis of BP was associated with a superior OS (40.0% vs. 26.0% P = 0.011 for 1-year OS from BP). Allogeneic hematopoietic stem cell transplantation (HSCT) was performed in 13 patients, and the 1-year OS from allogeneic HSCT was 61.5%. The hazard ratio for mortality was 0.34 (95% CI, 0.08–1.51, P = 0.15) for allogeneic HSCT treated as a time-dependent covariate, which suggests that allogeneic HSCT may confer a clinical benefit. Conclusion: The further accumulation of clinical data is needed to determine the optimal therapeutic approach for these neoplasms.

A leukemic double-hit follicular lymphoma associated with a complex variant translocation, t(8;14;18)(q24;q32;q21), involving BCL2, MYC, and IGH

Double-hit lymphoma (DHL) is defined as lymphoma with concurrent BCL2 and MYC translocations. While the most common histological subtype of DHL is diffuse large B-cell lymphoma, the present patient had leukemic follicular lymphoma (FL). A 52-year-old man was admitted to our hospital due to general fatigue and cervical and inguinal lymph node swelling. The patient was leukemic and the pathological diagnosis of the inguinal lymph node was FL grade 1. Chromosomal analysis revealed a complex karyotype including a rare three-way translocation t(8;14;18)(q24;q32;q21) involving the BCL2, MYC, and IGH genes. Based on a combination of fluorescence in situ hybridization (FISH), using BCL2, MYC and IGH, and spectral karyotyping (SKY), the karyotype was interpreted as being the result of a multistep mechanism in which the precursor B-cell gained t(14;18) in the bone marrow and acquired a translocation between der(14)t(14;18) and chromosome 8 in the germinal center, resulting in t(8;14;18). The pathological diagnosis was consistently FL, not only at presentation but even after a second relapse. The patient responded well to standard chemotherapies but relapsed after a short remission. This patient is a unique case of leukemic DH-FL with t(8;14;18) that remained in FL even at a second relapse.

CD25 as an adverse prognostic factor in elderly patients with acute myeloid leukemia.

ABSTRACT Objectives: CD25 has been reported to be highly expressed in leukemia stem cells and correlated with adverse outcomes in young patients with acute myeloid leukemia (AML). However, the significance of CD25 expression in elderly patients with AML has not yet been investigated. Methods: We retrospectively analyzed 154 newly diagnosed AML patients aged 60 years or over by flow cytometry. Results: CD25-positive AML was characterized by high white blood cell counts, secondary AML, rare favorable karyotypes, and positivity for CD34 and CD7 antigens, compared with CD25-negative AML. CD25 positivity was significantly correlated with an inferior complete remission (CR), event-free survival (EFS), and overall survival. Multivariate analysis showed CD25 positivity to be a significant prognostic predictor of CR and EFS. A regimen of low-dose cytarabine and aclarubicin combined with granulocyte-colony-stimulating factor (CAG) led to higher CR rates in the CD25-positive AML patients than intensive chemotherapies. CD25 expression was increased at relapse and in the development of leukemic status from myelodysplastic syndrome or myeloproliferative neoplasm. Discussion: An effective treatment strategy for elderly patients with CD25-positive AML has not been established. Further studies are needed to evaluate the effect of a CAG regimen and allogenic stem cell transplantation in patients. Conclusion: CD25 is an independent prognostic factor in elderly AML patients. Alternative therapies for CD25-positive elderly AML patients are needed.

A low-dose cytarabine, aclarubicin and granulocyte colony-stimulating factor priming regimen versus a daunorubicin plus cytarabine regimen as induction therapy for older patients with acute myeloid leukemia: A propensity score analysis

This retrospective analysis compared the efficacy of intensive induction therapy consisting of daunorubicin and cytarabine (DNR-AraC) to that of less-intensive therapy including low-dose cytarabine, aclarubicin and granulocyte colony-stimulating factor priming (CAG). Patients aged 60 years or older who were newly diagnosed as acute myeloid leukemia (AML) were analyzed. Sixty-four and 48 patients were treated with DNR-AraC and CAG, respectively. The complete remission rates, 3-year overall survival and event-free survival in the DNR-AraC group were significantly superior to those in the CAG group (65.6% vs. 29.2%, p<0.001, 38.4% vs. 12.3%, p=0.0033, and 20.3% vs. 7.8%, p=0.0030, respectively), although these differences were not statistically significant in multivariate analyses. Next, we calculated a propensity score for selecting the CAG regimen from six factors. The DNR-AraC regimen was associated with better survival than the CAG regimen in a low propensity score group, but there was no difference in survival between regimens in a high propensity score group. Intensive therapy should be performed for patients with sufficient general and comorbid conditions, but less-intensive therapy may be sufficient for patients with higher age, myelodysplasia-related changes, and lower white blood cell counts, which were relevant factors in the propensity score calculation.

Comprehensive Analysis of the Activation and Proliferation Kinetics and Effector Functions of Human Lymphocytes, and Antigen Presentation Capacity of Antigen-Presenting Cells in Xenogeneic Graft-Versus-Host Disease

Xenogeneic graft-versus-host disease (GVHD) models in highly immunodeficient mice are currently being used worldwide to investigate human immune responses against foreign antigens in vivo. However, the individual roles of CD4+ and CD8+ T cells, and donor/host hematopoietic and nonhematopoietic antigen-presenting cells (APCs) in the induction and development of GVHD have not been fully investigated. In the present study, we comprehensively investigated the immune responses of human T cells and the antigen presentation capacity of donor/host hematopoietic and nonhematopoietic APCs in xenogeneic GVHD models using nonobese diabetic/Shi-scid-IL2rgnull mice. CD4+ T cells and, to a lesser extent, CD8+ T cells individually mediated potentially lethal GVHD. In addition to inflammatory cytokine production, CD4+ T cells also supported the activation and proliferation of CD8+ T cells. Using bone marrow chimeras, we demonstrated that host hematopoietic, but not nonhematopoietic, APCs play a critical role in the development of CD4+ T cell-mediated GVHD. During early GVHD, we detected 2 distinct populations in memory CD4+ T cells. One population was highly activated and proliferated in major histocompatibility complex antigen (MHC)+/+ mice but not in MHC-/- mice, indicating alloreactive T cells. The other population showed a less activated and slowly proliferative status regardless of host MHC expression, and was associated with higher susceptibility to apoptosis, indicating nonalloreactive T cells in homeostasis-driven proliferation. These observations are clinically relevant to donor T cell response after allogeneic hematopoietic stem cell transplantation. Our findings provide a better understanding of the immunobiology of humanized mice and support the development of novel options for the prevention and treatment for GVHD.

Prognostic value of the soluble interleukin-2 receptor level after patients with follicular lymphoma achieve a response to R-CHOP

ABSTRACT Objectives: Follicular lymphoma (FL) is a clinically and biologically heterogeneous disease. Therefore, it is important to identify factors that can predict its clinical outcome. Methods: We retrospectively evaluated the usefulness of soluble interleukin-2 receptor (sIL-2R) levels after R-CHOP (posttreatment sIL-2R) in 72 patients with newly diagnosed FL who had either a complete response (CR) or partial response. With the use of a recursive partitioning analysis, we determined the cut-off values of post- and pretreatment sIL-2R levels that were associated with disease progression, which corresponded to 486.5 and 5405 U/mL, respectively. Results: The high posttreatment sIL-2R group showed a significantly inferior progression-free survival (PFS) compared to the low posttreatment sIL-2R group in all patients (3-year PFS 52.6% vs. 77.4%, P = 0.003), and in patients with CR (3-year PFS 57.1% vs. 82.1%, P = 0.034). Although a multivariate analysis showed that pretreatment sIL-2R, but not posttreatment sIL-2R, was an independently significant predictive factor for disease progression, among patients with low pretreatment sIL-2R levels, those with high posttreatment sIL-2R levels tended to have inferior PFS. There was a significant trend in PFS among the high pretreatment sIL-2R group, the low pre- and high posttreatment sIL-2R group, and the low pre- and low posttreatment sIL-2R group (P < 0.001). Conclusion: Among patients with a low pretreatment sIL-2R level who exhibited a positive response to R-CHOP, the posttreatment sIL-2R level may help to identify those with a poor prognosis.

High-Dose Methotrexate and Cytarabine-Based Multi-Agent Chemotherapy (Modified Bonn Protocol) for Systemic Lymphoma with CNS Involvement

The prognosis of patients with systemic lymphoma with central nervous system (CNS) involvement is very poor and there is no established standard therapy. We retrospectively analyzed 18 patients (4 untreated and 14 relapsed) with systemic lymphoma with CNS involvement who received methotrexate and cytarabine-based multiagent chemotherapy (modified Bonn protocol). Complete and partial responses were achieved in 56 and 22% of the patients, respectively. The 1-year overall survival (OS) and progression-free survival (PFS) was 81.0 and 39.2%, respectively. Patients with parenchymal involvement showed a better 1-year PFS than those with either leptomeningeal involvement or both. In a multivariate analysis, poor performance status (PS) was the only independent prognostic factor for the 1-year OS and PFS (HR 10.8, 95% CI 1.09-108, p = 0.042; HR 20.8, 95% CI 2.39-181, p = 0.006, respectively). Grade 4 neutropenia and thrombocytopenia occurred in 17 patients each (94%), but there were no grade 4 nonhematopoietic adverse events. The modified Bonn protocol resulted in relatively favorable response and survival, and provided clinical benefits to patients with good PS, in particular. This study demonstrated that the modified Bonn protocol could be a feasible and encouraging treatment approach for lymphoma with CNS and systemic involvement.