Challenges in overcoming advanced-stage or relapsed refractory extranodal NK/T-cell lymphoma: meta-analysis of individual patient data.

Introduction: Extranodal NK/T-cell lymphoma (ENKTCL), a non-Hodgkin lymphoma, is known for its destructive local impact on nasal structures and systemic induction of inflammatory cytokines. Concurrent treatment with radiation and nonanthracycline- based chemotherapy has improved survival rates in patients with localized disease stages. However, survival outcomes vary significantly in advanced-stage and relapsed or refractory (R/R) cases. Methods: Therefore, we conducted a meta-analysis using random effects models to assess prognostic factors in advanced or R/R ENKTCL, employing a digital extractor on Kaplan-Meier graphs owing to the scarcity of published prospective trials for these patients. Results: We observed that patients with advanced ENKTCL treated with Lasparaginase had a median progression-free survival (PFS) of 14.3 months and an overall survival (OS) of 19 months. In R/R ENKTCL, PFS and OS were 11.7 and 15.6 months, respectively. Additionally, OS outcomes in advanced-stage ENKTCL were better in the asparaginase group than that in the non-asparaginase group, with PEG-asparaginase showing superior results compared with that using Lasparaginase. Epstein-Barr Virus (EBV)-DNA positivity in the bloodstream prior to treatment was associated with poor outcomes in advanced-stage ENKTCL, and similar trends were observed in patients with R/R ENKTCL and post-treatment EBV viremia. Discussion: Collectively, these findings suggest that chemotherapy with Lasparaginase or PEG-asparaginase can enhance survival in advanced or R/R ENKTCL. However, future strategies must be developed to effectively suppress EBV viremia and achieve a deep response toward tumor eradication.

Comparative analysis of reduced toxicity conditioning regimens between fludarabine plus melphalan and fludarabine plus busulfex in adult patients with acute lymphoblastic leukemia.

Reduced-toxicity conditioning (RTC) regimens aim to mitigate regimen-related toxicity while maintaining anti-leukemic efficacy in allogeneic hematopoietic stem cell transplantation (allo-HSCT). We assessed outcomes of RTC regimens utilizing melphalan versus intravenous busulfan combined with fludarabine in adult acute lymphoblastic leukemia (ALL) patients. A retrospective analysis was conducted with 149 consecutive adult ALL patients (median age 51, range 18-60) in remission undergoing allo-HSCT. Patients received either fludarabine 150 mg/BSA plus 2 days of melphalan 70 mg/BSA (FM140, n = 76) from 2009 to 2015 or fludarabine plus 3 days of busulfan 3.2 mg/kg (FB9.6, n = 73) from 2016 to 2021. At 5 years post-HSCT, FM140 demonstrated superior disease-free survival (53.4% vs. 30.5%, p = 0.007) and lower cumulative relapse (27.4% vs. 46.8%, p = 0.026) than FB9.6. Five-year overall survival and non-relapse mortality did not significantly differ. FM140 exhibited a higher incidence of acute graft-versus-host disease (GVHD) grades II-IV (49.3% vs. 30.3%, p = 0.016), though rates of acute GVHD grades III-IV and chronic GVHD were similar. Multivariate analysis identified Philadelphia chromosome and minimal residual disease positive status, and FB9.6 conditioning as predictors of increased relapse and poorer disease-free survival. FM140 RTC regimen displayed significantly reduced relapse and superior disease-free survival compared to FB9.6 in ALL patients undergoing allo-HSCT, highlighting its current clinical utility.

Mesenchymal stem cells preconditioned with a TLR5 agonist enhanced immunoregulatory effect through M2 macrophage polarization in a murine graft-versus-host disease model.

Graft-versus-host disease (GVHD) is a common complication following hematopoietic stem cell transplantation and can be life-threatening. Mesenchymal stem cells (MSCs), adult stem cells with immunomodulatory properties, have been used as therapeutic agents in a variety of ways and have demonstrated efficacy against acute GVHD (aGVHD); however, variability in MSC pro- and anti-inflammatory properties and the limitation that they only exhibit immunosuppressive effects at high levels of inflammation have prevented their widespread clinical use. The outcomes of GVHD treated with MSCs in the clinic have been variable, and the underlying mechanisms remain unclear. Therefore, the unique biological effects of Toll-like receptor 5 (TLR5) agonists led us to compare and validate the efficacy of MSCs primed with KMRC011, a TLR5 agonist. KMRC011 is a stimulant that induces the secretion of cytokines, which play an important role in immune regulation. In this study, we found that MSCs pretreated with KMRC011 increased the secretion of immunosuppressive cytokines indoleamine 2,3-dioxygenase (IDO) and cyclooxygenase-2 (COX2) and increased the expression of M2 macrophage polarizing cytokines macrophage colony-stimulating factor (M-CSF) and interleukin 10 (IL-10) in vitro. We investigated the immunosuppressive effects of TLR5 agonist (KMRC011)-primed MSCs on lymphocytes and their preventive and therapeutic effects on an in vivo mouse aGVHD model. In vitro experiments showed that KMRC011-primed MSCs had enhanced immunosuppressive effects on lymphocyte proliferation. In vivo experiments showed that KMRC011-primed MSCs ameliorated GVHD severity in a mouse model of induced GVHD disease. Finally, macrophages harvested from the spleens of mice treated with KMRC011-primed MSCs showed a significant increase in the anti-inflammatory M2 phenotype. Overall, the results suggest that KMRC011-primed MSCs attenuated GVHD severity in mice by polarizing macrophages to the M2 phenotype and increasing the proportion of anti-inflammatory cells, opening new horizons for GVHD treatment.

Repeated Infusions of Bone-Marrow-Derived Mesenchymal Stem Cells over 8 Weeks for Steroid-Refractory Chronic Graft-versus-Host Disease: A Prospective, Phase I/II Clinical Study.

Chronic graft-versus-host disease (cGVHD) is a long-term complication of allogeneic hematopoietic stem cell transplantation associated with poor quality of life and increased morbidity and mortality. Currently, there are several approved treatments for patients who do not respond to steroids, such as ruxolitinib. Nevertheless, a significant proportion of patients fail second-line treatment, indicating the need for novel approaches. Mesenchymal stem cells (MSCs) have been considered a potential treatment approach for steroid-refractory cGVHD. To evaluate the safety and efficacy of repeated infusions of MSCs, we administered intravenous MSCs every two weeks to ten patients with severe steroid-refractory cGVHD in a prospective phase I clinical trial. Each patient received a total of four doses, with each dose containing 1 × 106 cells/kg body weight from the same donor and same passage. Patients were assessed for their response to treatment using the 2014 National Institutes of Health (NIH) response criteria during each visit. Ten patients with diverse organ involvement were enrolled, collectively undergoing 40 infusions as planned. Remarkably, the MSC infusions were well tolerated without severe adverse events. Eight weeks after the initial MSC infusion, all ten patients showed partial responses characterized by the amelioration of clinical symptoms and enhancement of their quality of life. The overall response rate was 60%, with a complete response rate of 20% and a partial response (PR) rate of 40% at the last follow-up. Overall survival was 80%, with a median follow-up of 381 days. Two patients died due to relapse of their primary disease. Immunological analyses revealed a reduction in inflammatory markers, including Suppression of Tumorigenicity 2 (ST2), C-X-C motif chemokine ligand (CXCL)10, and Secreted phosphoprotein 1(SPP1), following the MSC treatment. Repeated MSC infusions proved to be both feasible and safe, and they may be an effective salvage therapy in patients with steroid-refractory cGVHD. Further large-scale clinical studies with long-term follow-up are needed in the future to determine the role of MSCs in cGVHD.

The IL-6 signaling pathway contributes critically to the immunomodulatory mechanism of human decidua-derived mesenchymal stromal cells.

Human bone marrow-derived mesenchymal stromal cells (BM-MSCs) have been proposed as a treatment for graft-versus-host disease (GVHD), which is a major complication following allogeneic hematopoietic cell transplantation. However, clinical trials have not yielded good results, and human decidua-derived mesenchymal stromal cells (DSCs) have been proposed as an alternative. In addition, the mechanism by which DSCs exert their immunomodulatory effects is still unknown. We found that knockdown of IL-6 in DSCs reduced the expression of PD-L1 and PD-L2, which are known as classical immune checkpoint inhibitors. Expression of PD-L1 and PD-L2 was restored by adding recombinant IL-6 to the DSCs. When DSCs and IL-6-knockdown DSCs were administered as treatment in a murine GVHD model, the group receiving IL-6-knockdown DSCs had significantly higher mortality and clinical scores compared to the group receiving DSCs. Taken together, these data suggest that the IL-6 signaling pathway is a crucial contributor to the immunosuppressive capacity of DSCs.

TLR5 agonist in combination with anti-PD-1 treatment enhances anti-tumor effect through M1/M2 macrophage polarization shift and CD8+ T cell priming.

Immune checkpoint inhibitors have revolutionized anti-tumor therapy, notably improving treatment responses in various tumors. However, many patients remain non-responsive and do not experience benefits. Given that Toll-like receptors (TLRs) can counteract tumor immune tolerance by stimulating both innate and adaptive immune responses, TLR agonists are being explored as potential immune adjuvants for cancer treatment. In this study, we assessed the potential of enhancing the efficacy of immune checkpoint inhibitors by activating innate immunity with a TLR5 agonist. In a mouse tumor model, combination therapy with TLR5 agonist and anti-PD-1 significantly inhibited tumor growth. The TLR5 agonist shifted the balance from M2-like to M1-like macrophages and upregulated the expression of co-stimulatory molecules in macrophages. Furthermore, TLR5 agonist promoted the activation and tumor infiltration of CD8+ T cells. As a result, the TLR5 agonist augmented the anti-tumor efficacy of anti-PD-1, suggesting its potential in modulating the tumor microenvironment to enhance the anti-tumor response. Our findings point toward the possibility of optimizing immune checkpoint inhibitor therapy using TLR5 agonists.

Reduced toxicity (FluBu3) versus myeloablative (BuCy) conditioning in acute myeloid leukemia patients who received first allogeneic hematopoietic stem cell transplantation in measurable residual disease-negative CR1.

In the present study, reduced toxicity (FluBu3) and myeloablative (BuCy) conditioning were compared in patients with AML who received first allogeneic HSCT in MRD-negative CR1. The study included 124 adult patients who underwent HSCT from an HLA-matched (8/8) sibling, unrelated, or 1-locus mismatched (7/8) unrelated donor (MMUD). The median age was 45 years and intermediate cytogenetics comprised majority (71.8%). The 2-year OS, RFS, CIR and NRM for BuCy (n = 78, 62.9%) and FluBu3 (n = 46, 37.1%) groups were 78.3% and 84.5% (p = 0.358), 78.0% and 76.3% (p = 0.806), 7.7% and 21.5% (p = 0.074) and 14.3% and 2.2% (p = 0.032), respectively. At the time of data cut-off, relapse and NRM were the main causes of HSCT failure in each of the FluBu3 and BuCy arms. Among patients, 75% of relapsed FluBu3 patients had high-risk features of either poor cytogenetics or FLT3-ITD mutation compared with 16.7% of BuCy patients. The majority of NRM in the BuCy group was due to GVHD (73%), half of whom received MMUD transplantation. To conclude, the FluBu3 reduced toxicity conditioning showed comparable post-transplant OS and RFS to BuCy and was associated with significantly reduced NRM that was offset by a trend towards higher risk of relapse even in MRD-negative CR1 population.

Long-term Clinical Outcomes of Optimizing Combination Therapy for Primary Pulmonary Mucosa-associated Lymphoid Tissue Lymphoma: A Retrospective Study.

INTRODUCTION: Pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma progresses with advancing disease stage. However, no standard treatment approach has been established. This single-center retrospective study evaluated clinical and radiological characteristics, treatment modalities, and long-term prognosis of pulmonary MALT lymphoma. METHODS: The study included 42 patients diagnosed with pulmonary MALT lymphoma between October 2004 and July 2019. Primary therapeutic modalities were determined using modified Ann Arbor staging. Therapeutic response was evaluated via computed tomography and laboratory analyses every 6 months for 5 years. Radiological findings were categorized based on the Lugano classification as complete response (CR), partial response, stable disease (SD), or progressive disease. RESULTS: Initial treatment included observation (n=2), surgical resection (n=6), or systemic chemotherapy (n=34). Patients treated surgically had localized disease and achieved initial and long-term CR. Of the 34 patients who underwent chemotherapy, 30 achieved CR, 2 achieved SD, and 2 died. Overall and progression-free survival (PFS) rates were 93.9% and 54.3%, respectively. Multivariate analysis indicated that PFS was lower in patients with modified Ann Arbor stage III-IV lymphoma and those who did not achieve CR. CONCLUSIONS: Optimized treatment based on anatomical location, pulmonary function, and disease stage can improve long-term survival in patients with pulmonary MALT lymphoma.

Dynamic changes in physical function during intensive chemotherapy affect transplant outcomes in older adults with AML.

Introduction: Intensive chemotherapy (IC) can affect all geriatric assessment (GA) domains in older adults with acute myeloid leukemia (AML), but data on the effects of these changes on transplant outcomes are lacking. Methods: Therefore, we prospectively assessed the prognostic role of GA domains at diagnosis and allogeneic hematopoietic stem cell transplantation (allo-HSCT) in 51 patients with AML aged ≥60 years who achieved complete remission after IC. We performed both baseline and pre-allo-HSCT GA; moreover, physical function, including a short physical performance battery (SPPB), cognitive function, psychological function, nutritional status, and social support were examined. Results: All GA domains showed dynamic changes between the two time points. The directions of change were statistically significant for social support, self-reported physical and psychological functions, and distress, but not for nutritional status, cognitive function, or physical function. Among all GA domains at each time point, only poor physical function and its submaneuvers at diagnosis but not at allo-HSCT were significantly associated with inferior survival. In particular, since the direction of change varied between patients, we found that patients whose physical function improved before allo-HSCT were more likely to survive longer than those with persistently impaired SPPB (55.6% vs. 28.6%, p=0.268). Finally, persistent impairment in SPPB (28.6% vs. 65.9%, p=0.006), tandem stand (0% vs. 63.3%, p=0.012), sit-and-stand (41.2% vs. 70.6%, p=0.009), and gait speed (38.5% vs. 68.4%, p=0.027) further strongly predicted inferior survival. Discussion: This study showed that IC courses can induce dynamic changes in different directions in the GA domains of each patient and that changes in objectively measured physical function can predict transplant outcomes.

The salvage role of allogeneic hematopoietic stem-cell transplantation in relapsed/refractory diffuse large B cell lymphoma.

To clarify the role of allogeneic hematopoietic stem-cell transplantation (allo-HSCT) in the chimeric antigen receptor T-cell therapy era, we analyzed the clinical characteristics and outcomes of 52 patients treated with allo-HSCT with relapsed/refractory diffuse large B cell lymphoma. Most enrolled patients had previously undergone intensive treatments, the median number of chemotherapy lines was 4, and the median time from diagnosis to allo-HSCT was 27.1 months. Patients were divided into remission-achieved (n = 30) and active-disease (n = 22) groups before allo-HSCT. Over a median follow-up period of 38.3 months, overall survival (OS) and event-free survival (EFS) rates were 38.4% and 30.6%, respectively. The cumulative incidence of relapse (CIR) and the non-relapsed mortality (NRM) were 36.7% and 32.7%, respectively. OS, EFS, and graft-versus-host disease-free, relapse-free survival (GRFS) outcomes were significantly superior in the remission-achieved group with lower CIR. In a multivariate analysis, a shorter interval from diagnosis to allo-HSCT reflected relatively rapid disease progression and showed significantly poor OS and EFS with higher CIR. Patients with active disease had significantly lower EFS, GRFS, and higher CIR. Previous autologous stem-cell transplantation was associated with better GRFS. Allo-HSCT is an established modality with a prominent group of cured patients and still has a role in the CAR T-cell era, particularly given its acceptable clinical outcomes in young patients with chemo-susceptible disease.