Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has improved survival for patients with hematological malignancy, especially for those highly at risk of relapse. However, disease ...relapse after allo-HSCT remains the most common cause of treatment failure and death, even with conventional chemotherapy and donor lymphocyte infusion. Disease relapse in allo-HSCT can be reduced via pre-emptive treatment based on measurable residual disease and maintenance therapy for patients at high risk of relapse as promising treatment strategies. Recently, the development of novel agents and cellular therapies with high antitumor activity and less toxicity, which can be used in the post-transplant setting, has increased their clinical applications in the therapeutic approach. This review examines the current landscape and future strategies for maintenance therapy, mainly for AML and ALL after allo-HSCT.
We report here that in chronic lymphocytic leukemia (CLL), the propensity to generate clonal B cells has been acquired already at the hematopoietic stem cell (HSC) stage. HSCs purified from patients ...with CLL displayed lymphoid-lineage gene priming and produced a high number of polyclonal B cell progenitors. Strikingly, their maturation into B cells was restricted always to mono- or oligo-clones with CLL-like phenotype in xenogeneic recipients. These B cell clones were independent of the original CLL clones because they had their own immunoglobulin VDJ genes. Furthermore, they used preferentially VH genes frequently used in human CLL, presumably reflecting the role of B cell receptor signaling in clonal selection. These data suggest that HSCs can be involved in leukemogenesis even in mature lymphoid tumors.
► HSCs in CLL have cell-intrinsic propensity to generate clonal CLL-like B cells ► Abnormal karyotypes are not required for appearance of such B cell clones ► The majority of single HSCs in patients with CLL display lymphoid-lineage priming ► HSCs can be involved in oncogenesis even in mature lymphoid tumors
Prophylactic use of letermovir (LMV) markedly reduces the incidence of early clinically significant cytomegalovirus (csCMV) infection within the first 100 days after allogeneic hematopoietic cell ...transplantation (allo-HCT), which improves transplant outcomes. However, some patients eventually develop late-csCMV infection (beyond day 100) after completing LMV prophylaxis. To assess the incidence of late-csCMV infection as well as its risk factors and impacts on transplant outcome, a total of 81 allo-HCT recipients who had not developed early csCMV infection during LMV prophylaxis were retrospectively analyzed. Among them, 23 (28.4%) patients developed late-csCMV infection (until day 180) at a median time of 131 days after transplantation and 30 days after LMV discontinuation, respectively. Late-csCMV infection was correlated with apparent delayed immune reconstitution: patients transplanted from HLA-mismatched donors (hazard ratio HR = 13.0,
p
= 0.011) or CMV-IgG-negative donors (HR = 2.39,
p
= 0.043) had a significantly higher risk. In this study, transplant outcomes did not differ between patients with and without late-csCMV infection. This suggests a need to clarify the efficacy of extended administration of LMV for preventing late-csCMV infection in a larger number of allo-HCT recipients, especially those with “high-risk” donors.
Chemotherapy-induced nausea and vomiting (CINV) are generally evaluated according to the Common Terminology Criteria for Adverse Events (CTCAE). The Multinational Association for Supportive Care in ...Cancer (MASCC) developed the MASCC Antiemesis Tool (MAT) to facilitate recognition for CINV between patients and oncology specialists. In the present study, MAT and CTCAE were comparatively assessed in Japanese patients with hematological malignancies. A total of 61 patients were eligible for this study. The CTCAE data were collected from an electronic medical record system. The patients were asked to complete the Japanese version of MAT in the hospital, on the first and fourth days after the start of chemotherapy. The percentages of patients in whom nausea was completely controlled, with severity scores of zero, ranged from 70.5 to 82.0% for CTCAE and from 59.0 to 75.4% for MAT, during the first five days after the chemotherapy. The percentages of patients who had no vomiting ranged from 93.4 to 96.7% for CTCAE and from 90.2 to 98.4% for MAT. During the observation periods, the day-to-day response profiles of patients who received antiemetic treatment were comparable between CTCAE and MAT cohorts, and these two assessment tools showed good, positive correlations for nausea severity scores. The present study shows that the MAT is a useful tool for assessing the severity of CINV in patients with hematological malignancy, is comparable to CTCAE, and facilitates the identification of poor cancer care conditions by medical staff.
Post-transplant cytomegalovirus (CMV) disease can be almost completely avoided by current infection control procedures. However, CMV reactivation occurs in more than half of patients, and some ...patients can develop clinically resistant CMV infections. Whether resistance is due to the host’s immune status or a viral resistance mutation is challenging to confirm. Therefore, a prospective observational analysis of refractory CMV infection was conducted in 199 consecutive patients who received allogeneic hematopoietic stem cell transplantation at a single institution. Among them, 143 (72%) patients received anti-CMV drugs due to CMV reactivation, and only 17 (8.5%) exhibited refractory CMV infection. These patients had clinically refractory infection. However, viral genome analysis revealed that only one patient exhibited a mutation associated with the anti-CMV drug resistance. Clinical resistance was mainly correlated with host immune factors, and the incidence of resistance caused by gene mutations was low at the early stage after a transplantation.
Myeloid cell leukemia-1 (MCL-1) is an essential survival factor for hematopoiesis. In humans, hematopoietic stem cells (HSCs) express MCL-1 at the highest level in response to FMS-like tyrosine ...kinase-3 (FLT3) signaling. We here show that this FLT3-dependent stem cell maintenance system also plays a critical role in survival of leukemic stem cells (LSCs) in acute myeloid leukemia (AML). The CD34+CD38− LSC fraction expresses high levels of FLT3 as well as MCL-1, even compared with normal HSCs. Treatment with FLT3 ligand induced further MCL-1 up-regulation in LSCs in all AML cases tested. Interestingly, the group of samples expressing the highest levels of MCL-1 constituted AML with FLT3–internal tandem duplications (ITD). In FLT3-ITD AML cell lines, cells expressed a high level of MCL-1, and an inhibition of MCL-1 induced their apoptotic cell death. A tyrosine kinase inhibitor suppressed MCL-1 expression, and induced apoptosis that was reversed by the enforced MCL-1 expression. Finally, transduction of FLT3-ITD into HSCs strongly activated MCL-1 expression through its signal transducer and activator of transcription 5 (STAT5)–docking domains. This effect was completely abrogated when STAT5 activation was blocked. Thus, the acquisition of FLT3-ITD ensures LSC survival by up-regulating MCL-1 via constitutive STAT5 activation that is independent of wild-type FLT3 signaling.
Relapsed and refractory aggressive lymphoma have a poor prognosis. High-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (auto-HSCT) is effective in chemosensitive ...patients. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is among the few options for non-chemosensitive patients.
18
Fluoro-2-deoxy-
d
-glucose positron emission tomography–computed tomography (
18
FDG-PET/CT) is the standard tool for evaluating response to chemotherapy and residual tumor volume. However, accurate assessment of residual tumor volume is not currently being achieved in clinical practice, and its value in prognostic and therapeutic stratification remains unclear. To answer this question, we investigated the efficacy of quantitative indicators, including total metabolic tumor volume (TMTV), in predicting prognosis after auto-HSCT and allo-HSCT. We retrospectively analyzed 39 patients who received auto-HSCT and 28 who received allo-HSCT. In the auto-HSCT group, patients with a higher TMTV had a poor prognosis due to greater risk of relapse. In the allo-HSCT group, patients with a higher TMTV had a lower progression-free survival rate and a significantly higher relapse rate. Neither Deauville score nor other clinical parameters were associated with prognosis in either group. Therefore, pre-transplant TMTV on PET is effective for prognostic prediction and therapeutic decision-making for relapsed or refractory aggressive lymphoma.
Use of novel agents, including proteasome inhibitors and immunomodulatory drugs, has markedly improved outcomes in multiple myeloma (MM) patients. However, most MM patients eventually relapse and ...require salvage treatments. We report herein the result of a phase I/II study, performed from 2014 to 2017 to assess the feasibility and efficacy of a maximum tolerated dose (MTD) of lenalidomide (Len) combined with a fixed dose of once weekly subcutaneous (sc) 1.3 mg/m
2
of bortezomib plus 20 mg of dexamethasone (scVRd regimen) in relapsed/refractory MM patients in the Japanese population. In the phase I part, dose-limiting toxicities were observed in three of six patients treated with 20 mg of Len; the MTD was accordingly defined as 15 mg in our cohort. In the phase II part, the recommended dose of the scVRD regimen showed a 71.4% best overall response rate, with a median overall survival of 14.8 months and a median progression-free survival of 8 months. Severe adverse events (≥ grade 3) were observed in ~ 15% of the patients, indicating the tolerability and efficacy of the regimen. Less prior treatment was associated with higher probability of durable response. This scVRd regimen may thus be a better fit for MM patients in early-stage relapse.
The hedgehog signaling pathway regulates multiple morphogenetic processes during embryogenesis. Aberrant activation of the hedgehog pathway signal transduction in adult tissues is associated with the ...pathogenesis of hematologic malignancies and solid tumors. We report findings from an open‐label, multicenter phase I trial of the selective, small‐molecule hedgehog signaling inhibitor glasdegib (PF‐04449913) in Japanese patients with select advanced hematologic malignancies. Glasdegib was administered as once‐daily oral doses (25, 50 and 100 mg) in 28‐day cycles after a lead‐in dose on Day −5. The primary objectives were to determine first‐cycle dose‐limiting toxicities, safety, vital signs and laboratory test abnormalities. Secondary objectives included evaluation of pharmacokinetics, pharmacodynamics and preliminary evidence of clinical activity of glasdegib. No dose‐limiting toxicities were noted in the 13 patients in the present study. All patients experienced at least one treatment‐emergent, all‐causality adverse event. The most frequent treatment‐related adverse events (observed in ≥3 patients) were dysgeusia (n = 9), muscle spasms (n = 5), alopecia, decreased appetite (n = 4 each), and increased blood creatinine phosphokinase, constipation and diarrhea (n = 3 each). Two deaths occurred during the study and were deemed not to be treatment‐related due to disease progression. Glasdegib demonstrated dose‐proportional pharmacokinetics, marked downregulation of the glioma‐associated transcriptional regulator GLI1 expression in normal skin, and evidence of preliminary clinical activity, although data are limited. Glasdegib was safe and well tolerated across the dose levels tested. It is confirmed that the 100‐mg dose is safe and tolerable in Japanese patients, and this dose level will be examined in the future clinical trial.
We report findings from an open‐label, multicenter phase I trial of the selective, small‐molecule hedgehog signaling inhibitor glasdegib (PF‐04449913) in Japanese patients with select advanced hematologic malignancies. Glasdegib was administered as once‐daily oral doses (25, 50, and 100 mg) in 28‐day cycles after a lead‐in dose on Day –5. Glasdegib demonstrated dose‐proportional pharmacokinetics, marked downregulation of the glioma‐associated transcriptional regulator GLI1 expression in normal skin, and evidence of preliminary clinical activity, although data are limited. Glasdegib was safe and well tolerated across the dose levels tested.
To establish effective therapeutic strategies for eosinophil-related disorders, it is critical to understand the developmental pathway of human eosinophils. In mouse hematopoiesis, eosinophils ...originate from the eosinophil lineage-committed progenitor (EoP) that has been purified downstream of the granulocyte/macrophage progenitor (GMP). We show that the EoP is also isolatable in human adult bone marrow. The previously defined human common myeloid progenitor (hCMP) population (Manz, M.G., T. Miyamoto, K. Akashi, and I.L. Weissman. 2002. Proc. Natl. Acad. Sci. USA. 99:11872-11877) was composed of the interleukin 5 receptor alpha chain(+) (IL-5Ralpha(+)) and IL-5Ralpha(-) fractions, and the former was the hEoP. The IL-5Ralpha(+)CD34(+)CD38(+)IL-3Ralpha(+)CD45RA(-) hEoPs gave rise exclusively to pure eosinophil colonies but never differentiated into basophils or neutrophils. The IL-5Ralpha(-) hCMP generated the hEoP together with the hGMP or the human megakaryocyte/erythrocyte progenitor (hMEP), whereas hGMPs or hMEPs never differentiated into eosinophils. Importantly, the number of hEoPs increased up to 20% of the conventional hCMP population in the bone marrow of patients with eosinophilia, suggesting that the hEoP stage is involved in eosinophil differentiation and expansion in vivo. Accordingly, the phenotypic definition of hCMP should be revised to exclude the hEoP; an "IL-5Ralpha-negative" criterion should be added to define more homogenous hCMP. The newly identified hEoP is a powerful tool in studying pathogenesis of eosinophilia and could be a therapeutic target for a variety of eosinophil-related disorders.