Real-world Outcomes of Commercial Tisagenlecleucel for Children, Adolescents, and Young Adults With Acute Lymphoblastic Leukemia in Japan.

Chimeric antigen receptor (CAR) T cells are a major new treatment option for children, adolescents, and young adults (CAYA) patients with relapsed and refractory (R/R) B cell acute lymphoblastic leukemia (B-ALL). Therefore, accumulating evidence from real-world experiences of CAR-T outcomes in various regions worldwide is important, particularly when comparing outcomes of patients with differing medical and ethnic backgrounds. More than 5 years have passed since tisagenlecleucel was approved in Japan.

[Development of dual-targeted CAR T-cell therapy].

Chimeric antigen receptor T-cell therapy (CAR-T-cell therapy) has revolutionized the treatment of relapsed and refractory hematological malignancies. Targeting of the CD19 antigen on B cells has yielded high rates of remission induction and sustained remission in patients with acute lymphoblastic leukemia and B-cell lymphomas. Despite these remarkable responses, many escape mechanisms from CAR-T cell therapy have been identified, with the most common being target antigen deficiency.

MGMT protein expression is a reliable predictive biomarker for temozolomide-containing chemotherapy in osteosarcoma.

The prognosis of patients with osteosarcoma who experience recurrence or progression (R/P) is extremely poor, and more effective and less toxic therapies are needed. In the current study, the clinical data of osteosarcoma patients who experienced R/P were retrospectively analyzed to verify the reliability of O-6-methylguanine-DNA methyltransferase (MGMT) protein expression or MGMT promoter methylation for predicting the response to off-label temozolomide (TMZ)-containing chemotherapy. Of the 30 evaluable patients, 9 (30%) showed no/low MGMT protein expression, whereas all 16 evaluable patients had unmethylated MGMT promoter irrespective of MGMT protein expression levels.

Canonical BAF complex regulates the oncogenic program in human T-cell acute lymphoblastic leukemia.

Acute leukemia cells require bone marrow microenvironments, known as niches, which provide leukemic cells with niche factors that are essential for leukemic cell survival and/or proliferation. However, it remains unclear how the dynamics of the leukemic cell-niche interaction are regulated. Using a genome-wide CRISPR screen, we discovered that canonical BRG1/BRM-associated factor (cBAF), a variant of the switch/sucrose nonfermenting chromatin remodeling complex, regulates the migratory response of human T-cell acute lymphoblastic leukemia (T-ALL) cells to a niche factor CXCL12.

Safety and efficacy of post-haematopoietic cell transplantation maintenance therapy with blinatumomab for relapsed/refractory CD19-positive B-cell acute lymphoblastic leukaemia: protocol for a phase I-II, multicentre, non-blinded, non-controlled trial (JPLSG SCT-ALL-BLIN21).

Introduction: Relapsed and refractory B-cell acute lymphoblastic leukaemia (R/R-B-ALL) is linked to a significant relapse rate after allogeneic haematopoietic cell transplantation (allo-HCT) in children, adolescents and young adults (CAYA). No standard treatment has been established to prevent relapse after allo-HCT for R/R-B-ALL, which is an unmet medical need. The administration of blinatumomab after allo-HCT is expected to enhance the antileukaemic effect on residual CD19-positive blasts by donor-derived CD3-positive T-cells.

High-dose carboplatin-irinotecan-temozolomide is an effective salvage chemotherapy for relapsed or refractory neuroblastoma.

There is no clear consensus on the most effective treatment for relapsed/refractory high-risk neuroblastoma (NB). We retrospectively assessed seven NB patients with relapsed/refractory disease who received high-dose carboplatin-irinotecan-temozolomide (HD-CIT). Five of seven patients showed favorable therapeutic response (complete remission or partial remission).

Autologous Recovery With Chromosomal Abnormalities After Unrelated Umbilical Cord Blood Transplantation With Myeloablative Conditioning in a Case of Pediatric Acute Lymphoblastic Leukemia.

Detailed case reports of autologous recovery of hematopoiesis after hematopoietic stem cell transplantation with myeloablative conditioning are scarce. We present a rare case of a 3-year-old male with relapsed KMT2A -rearranged acute lymphoblastic leukemia who experienced autologous recovery following secondary engraftment failure after cord blood transplantation with myeloablative conditioning. Similar to prior reports, we detected unusual chromosomal abnormalities, which differed at each bone marrow examination.

[Knowledge and practice of patient-derived xenograft models in leukemia].

Patient-derived xenograft (PDX) models have gained attention due to their wide applications in basic research and drug development, and due to the increase in requirements for pathological analysis and anticancer drug evaluation. The development of immunodeficient mouse strains with high-level engraftment of normal and diseased cells has contributed to the considerable progress in understanding the human pathophysiology. The PDX model is one of the most important tools to bridge the gap between traditional animal models and the clinical trials.

Impact of human leukocyte antigen mismatch on outcomes after unrelated bone marrow transplantation in paediatric patients: A retrospective analysis by the JSTCT HLA working group.

The impact of human leukocyte antigen (HLA) mismatching at the HLA-A, -B, -C, and -DRB1 loci after unrelated bone marrow transplantation in paediatric patients with haematological malignancies has not been fully examined. Here, we analysed patients with haematological malignancies (all aged ≤15 years; n = 1330) who underwent a first unrelated bone marrow transplantation between 1993 and 2017 in Japan. The results show that although an HLA mismatch was significantly associated with a low relapse rate, it was also associated with higher non-relapse mortality.

The combination of ruxolitinib and Bcl-2/Mcl-1 inhibitors has a synergistic effect on leukemic cells carrying a SPAG9::JAK2 fusion.

JAK2 rearrangements can occur in Philadelphia chromosome-like acute lymphoblastic leukemia (Ph-like ALL). Here, we performed functional analysis of the SPAG9::JAK2 fusion, which was identified in a pediatric patient with Ph-like ALL, to establish molecular targeted therapy. Ba/F3 cells expressing SPAG9::JAK2 generated by retroviral transduction (Ba/F3-SPAG9-JAK2), proliferated in the absence of IL-3, and exhibited constitutive phosphorylation of the tyrosine residues in the JAK2 kinase domain of the fusion protein and STAT3/STAT5.

The first Japanese biobank of patient-derived pediatric acute lymphoblastic leukemia xenograft models.

A lack of practical resources in Japan has limited preclinical discovery and testing of therapies for pediatric relapsed and refractory acute lymphoblastic leukemia (ALL), which has poor outcomes. Here, we established 57 patient-derived xenografts (PDXs) in NOD.Cg-Prkdc ll2rg /ShiJic (NOG) mice and created a biobank by preserving PDX cells including three extramedullary relapsed ALL PDXs.

Use of Cabozantinib to Treat MET -amplified Pediatric Colorectal Cancer.

Pediatric colorectal cancer (CRC) is extremely rare, with little information about genetic profiles compared with adult CRC. Here, a 13-year-old male with advanced CRC underwent cancer gene panel testing, which detected 4 genetic abnormalities ( MET amplification in addition to TP53 , SMAD4 , and CTNNA1 mutations) that might be associated with a poor prognosis. Based on high-level MET amplification, he received a multikinase inhibitor, cabozantinib, after failure of first-line and second-line chemotherapy, resulting in transient disease stabilization.

A Clinically Applicable Prediction Model to Improve T Cell Collection in Chimeric Antigen Receptor T Cell Therapy.

As chimeric antigen receptor (CAR) T cell therapy targeting CD19 has shown favorable outcomes in patients with relapsed or refractory (r/r) mature B cell lymphomas and B cell acute lymphoblastic leukemia (B-ALL), an increasing number of patients are waiting to receive these treatments. Optimized protocols for T cell collection by lymphapheresis for chimeric antigen receptor (CAR) T cell therapy are urgently needed to provide CAR T cell therapy for patients with refractory and progressive disease and/or a low number of lymphocytes owing to prior chemotherapy. The predicted efficiency of CD3 cell collection in apheresis can guide protocols for apheresis, but a clinically applicable model to produce reliable estimates has not yet been established.

Ponatinib in pediatric patients with Philadelphia chromosome-positive leukemia: a retrospective survey of the Japan Children's Cancer Group.

Ponatinib is effective in adults with Philadelphia chromosome-positive (Ph+) leukemia, resistant or intolerant to second-generation tyrosine kinase inhibitors, but there are limited data on its use in children. The clinical courses of nine pediatric patients with Ph+ acute lymphoblastic leukemia (Ph+ ALL) and four with chronic myeloid leukemia (CML) who received ponatinib therapy were retrospectively reviewed. The median age at the start of ponatinib therapy was 12 years (range 8-16 years).