Effect of peptide-binding motif on survival of HLA-haploidentical transplantation with post-transplant cyclophosphamide.

Peptide-binding motif (PBM) model, a hierarchical clustering of HLA class I based on their binding specificity, was developed to predict immunopeptidome divergence. The effect of PBM mismatches on outcomes is unknown in HLA-haploidentical haematopoietic cell transplantation with post-transplant cyclophosphamide (PTCy-haplo). We therefore conducted a retrospective study using national registry data in PTCy-haplo. Overall, 1352 patients were included in the study. PBM-A bidirectional mismatch was associated with an increased risk of overall mortality in multivariable analysis (hazard ratio, 1.26; 95% confidence interval, 1.06 to 1.50; p = 0.010). None of relapse, non-relapse mortality (NRM) and graft-versus-host disease showed significant differences according to PBM-A bidirectional mismatch status in the entire cohort. The impact of PBM-A bidirectional mismatch on overall survival (OS) was preserved within the HLA-A genotype bidirectional mismatch population, and their lower OS stemmed from higher relapse rate in this population. The worse OS due to high NRM with PBM-A bidirectional mismatch was prominent in lymphoid malignancies receiving reduced-intensity conditioning. The PBM model may predict outcomes more accurately than HLA genotype mismatches. In conclusion, this study demonstrated that the presence of PBM-A bidirectional mismatch elevated the risk of mortality of PTCy-haplo. Avoiding PBM-A bidirectional mismatch might achieve better outcomes in PTCy-haplo.

Impact of microsampling on toxicological evaluation in rodent safety studies.

Recently, animal welfare has been attracting worldwide attention, and implementation of 3Rs (replacement, reduction, and refinement) is prioritized in every way possible in the drug development. Microsampling, in which small amounts of blood are collected, is attracting attention in this context. ICH S3A Q&A focused on microsampling was published in November 2017 to help accelerate the application of microsampling for toxicokinetic assessment. The increased sensitivity of drug measurement apparatuses such as mass spectrometers has made it possible to measure drug concentrations with small amounts of blood samples. In this review, we summarized the reports on toxicological influence of microsampling in rodents (rats and mice) with or without drug administration or recovery period after blood collection and influences that may arise from differences in the blood sampling site or blood sampling volume. We also summarized some perspectives on further implementation of microsampling in toxicology studies. The use of microsampling in regulatory toxicology studies has gradually increased, although at a lower rate than in discovery studies. Since more animals are used in GLP toxicology studies than in discovery studies, the effect of reducing the number of animals by microsampling is expected to be greater in the toxicology studies. This report aims to promote the application of microsampling to nonclinical studies, as it is beneficial for improving animal welfare and can contribute to the 3Rs.

High Ki-67 Expression Predicting a Risk Factor for the Progression of Disease within 24 Months and Microenvironment in Follicular Lymphoma.

Most follicular lymphomas (FLs) demonstrate an indolent clinical course with favorable outcomes; however, a fraction of patients experiences progression of disease within 24 months (POD24) and has adverse outcomes. This study aimed to determine the predictive risk factors for POD24 in patients with FL, and the characteristics of the microenvironment in FL with POD24. By multivariate analysis, we revealed that increased Ki-67 expression was associated with POD24 events in patients with FL (hazard ratio [HR]: 6.29, 95% confidence interval [CI]: 1.96-20.22, p = 0.0020). Additionally, patients with FL with POD24 demonstrated immune cell reduction by immunohistochemistry analysis. Our results help better understand the therapeutic strategies for FL with POD24.

[Acquired thrombotic thrombocytopenic purpura during durvalumab monotherapy for non-small cell lung cancer].

Immune checkpoint inhibitor (ICI)-induced thrombocytopenias are rare immune-related adverse events (irAE), but ICI-related thrombotic thrombocytopenic purpura (TTP) is extremely rare. A 79-year-old woman with non-small cell lung cancer received maintenance therapy with the anti-human PD-L1 monoclonal antibody durvalumab. Four weeks after the last infusion, she developed overt TTP. Remission was achieved by plasma exchange and prednisolone, and the patient has now been recurrence-free for over 12 months. To our knowledge, this is the first report of TTP occurring as an irAE of durvalumab.

[CD5- and CD10-positive MYC and BCL2 double-expressor diffuse large B-cell lymphoma with MYD88L265P mutation: a case report and literature review].

A 75-year-old man who had lymphadenopathy was admitted to our hospital. Histopathological examination of cervical lymph node biopsy specimens showed diffuse proliferation of lymphoma cells with large nuclei. In immunohistochemistry, the lymphoma cells were positive for CD5, CD10, CD20, BCL2, BCL6, and MYC. The patient was diagnosed with CD5- and CD10-positive diffuse large B-cell lymphoma (DLBCL). MYD88L265P mutations have been detected in DLBCL. Partial response was achieved after six courses of R-THP-COP therapy. However, the patient died because of disease progression 18 months after the diagnosis. On autopsy, lymphoma cells were found in the lymph nodes throughout the body, central nervous system, adrenals, and skin. CD5- and CD10-positive DLBCL account for 0.5-1% of DLBCL cases and have a very poor disease prognosis. This is a rare case of CD5- and CD10-positive DLBCL with MYC and BCL2 expressions harboring MYD88L265P mutation.

Single cord blood transplantation for acute myeloid leukemia patients aged 60 years or older: a retrospective study in Japan.

The availability of alternative donor sources could allow elderly patients to receive allogeneic hematopoietic cell transplantation (HCT). We retrospectively evaluated the outcomes of single-unit cord blood transplantation (CBT) in 1577 patients aged ≥60 years with acute myeloid leukemia (AML) in Japan between 2002 and 2017. In total, 990 (63%) patients were not in complete remission (CR) at the time of CBT. A myeloablative conditioning regimen (52%) and calcineurin inhibitor (CI) + mycophenolate mofetil (MMF)-based graft-versus-host disease (GVHD) prophylaxis (45%) were more commonly used. With a median follow-up for survivors of 31 months, the probability of overall survival and the cumulative incidence of leukemia-related mortality at 3 years was 31% and 29%, respectively. The cumulative incidence of non-relapse mortality (NRM) at 100 days and 3 years were 24% and 41%, respectively. The cumulative incidences of grade II-IV and grade III-IV acute GVHD at 100 days and extensive chronic GVHD at 2 years were 44%, 16%, and 14%, respectively. The cumulative incidence of neutrophil engraftment was 80% at 42 days. Results of multivariate analysis indicated that the following factors were significantly associated with higher overall mortality: performance status ≥1, hematopoietic cell transplantation-specific comorbidity index ≥3, adverse cytogenetics, extramedullary disease at diagnosis, and non-CR status at CBT. By contrast, female sex, HLA disparities ≥2, mycophenolate mofetil-based GVHD prophylaxis, and recent CBT were significantly associated with lower overall mortality. In conclusion, single CBT offers a curative option for AML patients aged ≥60 years with careful patient selection.

Candidatus Mycoplasma haemohominis in Human, Japan.

Hemotropic mycoplasmas are common pathogens in animals, but it remains unclear what role these pathogens play in human infections. We report clinical and biologic characterization of Candidatus Mycoplasma haemohominis infection in a 42-year-old man in Japan. The patient had severe hemophagocytic syndrome 1 month after an accidental needlestick injury. Metagenomic deep sequencing identified Candidatus M. haemohominis and determined its draft genome for an isolate from serum of the patient. A high copy number of the Candidatus M. haemohominis genome was detected in serum and bone marrow samples. Electron microscopy examination showed morphologic characteristics of Candidatus M. haemohominis. Levofloxacin monotherapy induced resistance caused by a gyrase A gene mutation in the quinolone resistance-determining region, but a combination treatment with moxifloxacin and minocycline was effective. We identified Candidatus M. haemohominis in a patient who had life-threatening symptoms related to multiple organ infection. Human infection with this mycoplasma might occur more frequently than has been generally recognized.

Comparative Study of Tacrolimus and Short-Term Methotrexate: 2-Day versus 3-Day Methotrexate as Graft-versus-Host-Disease Prophylaxis after Umbilical Cord Blood Transplantation in Adults.

Methotrexate (MTX) in combination with a calcineurin inhibitor has been commonly used for prophylaxis of graft-versus-host disease (GVHD) following umbilical cord blood transplantation (UCBT) in Japan. However, the appropriate prophylactic MTX dosage in UCBT has not been established to date. To determine the preferential GVHD prophylaxis in UCBT, this study retrospectively investigated the administration of short-term MTX for 2 days versus 3 days. Of 103 adult patients submitted to UCBT enrolled in the study, 73 received tacrolimus (TAC) with 2 days of MTX given at 10 mg/m2 on day 1 and 7 mg/m2 on day 3 (very short-term [vs] MTX), whereas 30 patients received TAC with 3 days of MTX given at 10 mg/m2 on day 1, 7 mg/m2 on day 3, and 7 mg/m2 on day 6 (short-term [s] MTX). In univariate analysis, neutrophil engraftment was shown to be significantly better (P = .039) in the vsMTX/TAC group. Among high-risk patients, the vsMTX/TAC group also exhibited earlier neutrophil engraftment (P = .042); however, the incidence of acute GVHD was higher in the vsMTX/TAC group (P = .035) on univariate analysis. In multivariate analysis, compared with sMTX/TAC, vsMTX/TAC was associated with lower risk of relapse (hazard ratio, .27; 95% confidence interval, .11 to .64; P = .003) . These results suggest that vsMTX/TAC can be appropriate GVHD prophylaxis after UCBT, especially in higher-risk patients.

Monitoring TIGIT/DNAM-1 and PVR/PVRL2 Immune Checkpoint Expression Levels in Allogeneic Stem Cell Transplantation for Acute Myeloid Leukemia.

After allogeneic stem cell transplantation (alloSCT), several immune checkpoints play an important role in the antileukemic immune response in the bone marrow (BM) microenvironment. However, immune checkpoint expression levels in the BM have not been reported after alloSCT in patients with acute myeloid leukemia (AML). We investigated the clinical impact of immune checkpoint expression in BM samples after alloSCT for AML. Higher expression of T cell immunoreceptor with Ig and ITIM domains (TIGIT) was associated with a decreased incidence of acute graft-versus-host disease (P = .048) and poor overall (P = .046) and progression-free survival (P = 0.024). In addition, higher expression of TIGIT at engraftment after alloSCT was correlated with a decreased number of natural killer cells in BM (P = .019). Monitoring TIGIT expression in the BM could be useful for predicting outcome after alloSCT for AML. Our findings raise the possibility that blockade of TIGIT would improve survival.

Natural Killer Immunotherapy for Minimal Residual Disease Eradication Following Allogeneic Hematopoietic Stem Cell Transplantation in Acute Myeloid Leukemia.

The most common cause of death in patients with acute myeloid leukemia (AML) who receive allogeneic hematopoietic stem cell transplantation (allo-HSCT) is AML relapse. Therefore, additive therapies post allo-HSCT have significant potential to prevent relapse. Natural killer (NK)-cell-based immunotherapies can be incorporated into the therapeutic armamentarium for the eradication of AML cells post allo-HSCT. In recent studies, NK cell-based immunotherapies, the use of adoptive NK cells, NK cells in combination with cytokines, immune checkpoint inhibitors, bispecific and trispecific killer cell engagers, and chimeric antigen receptor-engineered NK cells have all shown antitumor activity in AML patients. In this review, we will discuss the current strategies with these NK cell-based immunotherapies as possible therapies to cure AML patients post allo-HSCT. Additionally, we will discuss various means of immune escape in order to further understand the mechanism of NK cell-based immunotherapies against AML.

[Development of cardiac tamponade and emergence of arrhythmia during chemotherapy for diffuse large B-cell lymphoma].

Cardiac involvement during lymphoma often causes complications, including arrhythmia. A 68-year-old male with cardiac tamponade was diagnosed with diffuse large B-cell lymphoma with cardiac involvement based on the presence of the tumor mass in the myocardium and lymphoma cells in the pericardial effusion. He developed atrial fibrillation, ventricular tachycardia, and atrial flutter after initiating chemotherapy. Following chemotherapy, sinus rhythm was restored without invasive treatment for arrhythmia, while the cardiac mass disappeared. No recurrent arrhythmias were observed. In lymphoma with cardiac involvement, unexpected arrhythmias can emerge after initiation of chemotherapy, which could potentially be related to accelerated cardiac remodeling owing to the rapid relief of cardiac damage. Follow-up using electrocardiogram is thus necessary during chemotherapy for cardiac lymphoma, despite the absence of arrhythmia at the time of diagnosis.

Status of Natural Killer Cell Recovery in Day 21 Bone Marrow after Allogeneic Hematopoietic Stem Cell Transplantation Predicts Clinical Outcome.

Rapid immune recovery following allogeneic hematopoietic stem cell transplantation (allo-HSCT) is important for clinical outcome prediction. In most studies, immune recovery after allo-HSCT is monitored via peripheral blood. However, few reports regarding the status of absolute lymphocyte subsets in the bone marrow (BM) microenvironment have been undertaken. Therefore, we evaluated the clinical impact of immune recovery in the early period following allo-HSCT using BM samples. We showed that delayed natural killer cell recovery was independently associated with a poor prognosis for overall survival (hazard ratio [HR], 3.07; 95% confidence interval [CI], 1.37- 6.89; P = .007), progression-free survival (HR, 3.42; 95% CI, 1.47-7.94; P = .004), and nonrelapse mortality (HR, 6.68; 95% CI, 1.82-25.0; P = .004) by multivariate analysis. In addition, low NK cell counts were associated with the presence of 1 or more bacterial, viral, or fungal infections. Our results indicate that investigating absolute lymphocyte subsets in BM in the early phase following allo-HSCT can be useful for predicting and improving survival outcomes.

ASXL2 regulates hematopoiesis in mice and its deficiency promotes myeloid expansion.

Chromosomal translocation t(8;21)(q22;q22) which leads to the generation of oncogenic RUNX1-RUNX1T1 (AML1-ETO) fusion is observed in approximately 10% of acute myelogenous leukemia (AML). To identify somatic mutations that co-operate with t(8;21)-driven leukemia, we performed whole and targeted exome sequencing of an Asian cohort at diagnosis and relapse. We identified high frequency of truncating alterations in ASXL2 along with recurrent mutations of KIT, TET2, MGA, FLT3, and DHX15 in this subtype of AML. To investigate in depth the role of ASXL2 in normal hematopoiesis, we utilized a mouse model of ASXL2 deficiency. Loss of ASXL2 caused progressive hematopoietic defects characterized by myeloid hyperplasia, splenomegaly, extramedullary hematopoiesis, and poor reconstitution ability in transplantation models. Parallel analyses of young and >1-year old Asxl2-deficient mice revealed age-dependent perturbations affecting, not only myeloid and erythroid differentiation, but also maturation of lymphoid cells. Overall, these findings establish a critical role for ASXL2 in maintaining steady state hematopoiesis, and provide insights into how its loss primes the expansion of myeloid cells.

Association of Soluble Interleukin-2 Receptor and C-Reactive Protein with the Efficacy of Bendamustine Salvage Treatment for Indolent Lymphomas and Mantle Cell Lymphoma.

Bendamustine has demonstrated favourable efficacy in relapsed or refractory indolent lymphoma and mantle cell lymphoma. We retrospectively evaluated the pre-treatment clinical and laboratory factors and their correlation with the clinical outcome of these lymphomas. We analysed 53 patients who had been treated with bendamustine alone (n = 6) or rituximab plus bendamustine (n = 47). The overall response rate was 81.1%, with a complete response (CR) rate of 39.6%. The CR rate was significantly low in patients who had elevated levels of soluble interleukin-2 receptor (p = 0.024) and C-reactive protein (CRP; p = 0.004). The 1-year overall survival (OS) rate was 79.3%. An elevated CRP was associated with a short OS (p = 0.056). The present findings suggest that the lymphoma microenvironment and immune response were involved in the effects of bendamustine. These findings are also important in order to understand the pathophysiology of refractory lymphoma and to find effective strategies using bendamustine.

Efficacy of palonosetron to prevent delayed nausea and vomiting in non-Hodgkin's lymphoma patients undergoing repeated cycles of the CHOP regimen.

PURPOSE: Few studies have investigated the effect of palonosetron on delayed chemotherapy-induced nausea and vomiting in lymphoma patients receiving the CHOP regimen. We conducted a prospective clinical trial to assess the efficacy of palonosetron in patients receiving the CHOP regimen. METHODS: Complete control (CC: emesis-free and mild nausea) during delayed phase (24-120 h) was the primary endpoint. The secondary endpoint was complete response (CR: emesis-free) during acute (0-24 h), delayed, and overall phases (0-120 h), and CC during acute and overall phases. Palonosetron (0.75 mg) was administered before chemotherapy on day 1 of both the first and second CHOP cycles. RESULTS: The efficacy of palonosetron in preventing emesis was evaluated in 40 patients. Across two cycles, over 85% of patients achieved CR. As the primary endpoint, the proportion of patients achieving CC in the delayed phase increased from 70% (cycle 1) to 85% (cycle 2). CR rate in the delayed phase increased from 85% (cycle 1) to 95% (cycle 2). CONCLUSION: These results suggest that the antiemetic effects during the delayed phase were inferior to those in the acute phase during the first cycle. However, even at the same dose of palonosetron, CR and CC rates increased in the second cycle.

[Syndrome of inappropriate secretion of antidiuretic hormone in multiple myeloma patients treated with bortezomib, lenalidomide, and dexamethasone combination therapy].

Hyponatremia occurs while receiving bortezomib-containing combination therapy in multiple myeloma (MM) ; however, the mechanism of hyponatremia remains unclear. A 65-year-old female with MM was treated with bortezomib, lenalidomide, and dexamethasone. Fourteen days after chemotherapy initiation, she developed hyponatremia (serum sodium, 127 mEq/l, compared with 136 mEq/l before chemotherapy) with plasma hypo-osmolality and urine hyper-osmolality. She exhibited neither dehydration nor adrenal insufficiency. Her serum arginine vasopressin peptide (AVP) level was 1.5 pg/ml. She was diagnosed with syndrome of inappropriate secretion of antidiuretic hormone (SIADH), wherein causative roles of inflammatory cytokines were strongly suggested in the development because (1) SIADH was triggered by the cessation of the dexamethasone treatment and (2) hyponatremia was successfully treated with prednisolone, which was administered for the complication of drug eruption. Perhaps, bortezomib-induced immune reactions could be involved in a subset of hyponatremia during bortezomib-containing antimyeloma chemotherapy.

SETDB1 accelerates tumourigenesis by regulating the WNT signalling pathway.

We investigated the oncogenic role of SETDB1, focusing on non-small cell lung cancer (NSCLC), which has high expression of this protein. A total of 387 lung cancer cases were examined by immunohistochemistry; 72% of NSCLC samples were positive for SETDB1 staining, compared to 46% samples of normal bronchial epithelium (106 cases) (p <0.0001). The percentage of positive cells and the intensity of staining increased significantly with increased grade of disease. Forced expression of SETDB1 in NSCLC cell lines enhanced their clonogenic growth in vitro and markedly increased tumour size in a murine xenograft model, while silencing (shRNA) SETDB1 in NSCLC cells slowed their proliferation. SETDB1 positively stimulated activity of the WNT-ß-catenin pathway and diminished P53 expression, resulting in enhanced NSCLC growth in vitro and in vivo. Our finding suggests that therapeutic targeting of SETDB1 may benefit patients whose tumours express high levels of SETDB1.

Age and Bone Marrow Cellularity are Associated with Response to Eltrombopag in Japanese Adult Immune Thrombocytopenia Patients: A Retrospective Single-Center Study.

In the present retrospective single-center study, we examined the efficacy and safety of eltrombopag, a thrombopoietin (TPO) -receptor agonist (TPO-RA), and found clinical factors associated with its efficacy in Japanese patients with chronic immune thrombocytopenia (ITP). According to the definition of a response, which is to attain a platelet count of more than 50,000/µL at least once during eltrombopag treatment, 42 enrolled patients were divided into two groups: responders (29 patients, 69%) and non-responders (13 patients, 31%). In analyses of the clinical and laboratory data of these two groups, we extracted two factors that are significantly associated with a better response to eltrombopag, which have not been recognized previously, namely, (1) an older age of patients at eltrombopag initiation (≥ 70 years old) and (2) normal or decreased cellularity of iliac bone marrow (BM) biopsy at diagnosis. The significance of patient age contradicts previous findings from studies in which the Caucasian population was the major focus. However, factors such as changes of pharmacokinetics might modulate the effects of eltrombopag in older patients in Japan because East Asians show higher bioavailability of eltrombopag by as-yet-unknown mechanisms. BM cellularity in ITP may represent an impairment and/or lower responsiveness of pluripotent hematopoietic stem cells, not limited to the megakaryocyte (MgK) -platelet axis, to endogenous TPO, because recent evidence shows that TPO-RA can successfully restore hematopoiesis in aplastic anemia. These results should be useful for the therapeutic use of TPO-RA for ITP and also related thrombocytopenia in Japan.

Blastic Plasmacytoid Dendritic Cell Neoplasm in Long-Term Complete Remission After Venetoclax Monotherapy.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematological malignancy associated with a poor prognosis and limited treatment options. Although allogeneic hematopoietic stem cell transplantation or intensive chemotherapy prolongs overall survival in patients with BPDCN, intensive chemotherapy is inappropriate for older or unfit patients. Venetoclax (VEN), an oral BCL2 inhibitor, is approved for use in patients with acute myeloid leukemia (AML). BPDCN cells require BCL2 protein and are uniformly sensitive to VEN in vivo. Moreover, patients with AML who have achieved complete remission after induction therapy are reportedly considered to receive VEN monotherapy as maintenance therapy, especially older patients. However, the efficacy of VEN monotherapy as a maintenance therapy for patients with BPDCN remains controversial. Recently, BPDCN has been classified into MYC+ and MYC- subtypes, which show clinical differences. Hence, BPDCN treatment strategies based on the MYC classification may be necessary. Here, we report a case of MYC- BPDCN in an older patient in long-term complete remission after VEN monotherapy following VEN and azacitidine induction chemotherapy.