BACKGROUND: Several studies have demonstrated the occurrence of secondary tumors as a rare but significant complication of chimeric antigen receptor T (CAR-T) cell therapy, underscoring the need for a detailed investigation. Given the limited variety of secondary tumor types reported to date, a comprehensive characterization of the various secondary tumors arising after CAR-T therapy is essential to understand the associated risks and to define the role of the immune microenvironment in malignant transformation. This study aims to characterize the immune microenvironment of a newly identified secondary tumor post-CAR-T therapy, to clarify its pathogenesis and potential therapeutic targets. METHODS: In this study, the bone marrow (BM) samples were collected by aspiration from the primary and secondary tumors before and after CD19 CAR-T treatment. The CD45 + BM cells were enriched with human CD45 microbeads. The CD45 + cells were then sent for 10× genomics single-cell RNA sequencing (scRNA-seq) to identify cell populations. The Cell Ranger pipeline and CellChat were used for detailed analysis. RESULTS: In this study, a rare type of secondary chronic myelomonocytic leukemia (CMML) were reported in a patient with diffuse large B-cell lymphoma (DLBCL) who had previously received CD19 CAR-T therapy. The scRNA-seq analysis revealed increased inflammatory cytokines, chemokines, and an immunosuppressive state of monocytes/macrophages, which may impair cytotoxic activity in both T and natural killer (NK) cells in secondary CMML before treatment. In contrast, their cytotoxicity was restored in secondary CMML after treatment. CONCLUSIONS This finding delineates a previously unrecognized type of secondary tumor, CMML, after CAR-T therapy and provide a framework for defining the immune microenvironment of secondary tumor occurrence after CAR-T therapy. In addition, the results provide a rationale for targeting macrophages to improve treatment strategies for CMML treatment.
Humans ; Lymphoma, Large B-Cell, Diffuse/therapy* ; Tumor Microenvironment/genetics* ; Antigens, CD19/metabolism* ; Leukemia, Myelomonocytic, Chronic/genetics* ; Immunotherapy, Adoptive/adverse effects* ; Male ; Single-Cell Analysis/methods* ; Female ; Sequence Analysis, RNA/methods* ; Receptors, Chimeric Antigen ; Middle Aged

To analyze the clinical characteristics, diagnosis, treatment and outcome of patients with thrombotic thrombocytopenic purpura (TTP). The clinical data of 69 adult patients with TTP were retrospectively analyzed. There were 19 males and 50 females with a median age of 42 (18-79) years. PLASMIC score 6-7 was recognized in 82.8% (53/64) patients. The activity of von Willebrand factor-cleaving protease (ADAMTS13), which was detected in 21 patients before treatment, was less than 5% in 17 patients and 5%-10% in 3 patients. All 69 patients were treated with plasma exchange (PEX) and/or fresh frozen plasma infusion (PI), 43 of whom were also given glucocorticoid. In addition to PEX/PI and glucocorticoid, rituximab and/or immunosuppressants were administrated in 20 patients. The median follow-up time was 12 (1-57) months. The remission rate was 69.6%, while the relapse rate was 11.6%. The 2-year overall survival (OS) rate was 69.6%±5.5%. The univariate and multivariate analysis showed that relapsed/refractory disease was an independent risk factor for OS. The 2-year OS rate of relapsed/refractory patients was significantly lower than that of the rest patients (41.5%±9.8% vs. 83.7%±5.6%, P<0.001). Regarding the unfavorable prognosis in relapsed/refractory patients, rituximab and/or immunosuppressants are strongly recommended for sake of improving the overall survival.

Objective To investigate the efficacy and safety of domestic bortezomibˉbased chemotherapy for patients with multiple myeloma (MM). Methods The clinical data of 60 MM patients treated with domestic bortezomibˉbased chemotherapy regimen (the observation group) in the First Affiliated Hospital of Zhengzhou University from April 2018 to October 2018 were retrospectively analyzed, which were compared with 112 MM patients treated with original treatment regimen (the control group) at the same hospital from November 2010 to November 2014. According to the disease stage, the patients were divided into newly diagnosed MM (NDMM) group and relapsed refractory MM (RRMM) group, and efficacy and adverse reactions of domestic bortezomib were evaluated. Results The total response rate (ORR) of the observation group was 71.7% (43/60), severe complete response (sCR) + complete response (CR) rate was 16.7% (10/60), very good partial response (VGPR) rate was 18.3% (11/60), and partial response (PR) rate was 36.7% (22/60). The ORR of NDMM group (45 cases) and RRMM group (15 cases) was 82.2% (37/45) and 40.0% (6/15), respectively, and the difference was statistically significant (χ2＝ 9.877, P < 0.05). There was no significant difference between ISS stage Ⅰ+Ⅱ and stage Ⅲ [ORR: 75.7% (28/37) vs. 65.2% (15/23), respectively; χ2＝0.764, P >0.05]. ORR and CR rates in the NDMM group and RRMM group of the observation group and the control group were not statistically different (all P>0.05). In the treatment of bortezomibˉbased chemotherapy, the common adverse reaction was peripheral neuropathy, mostly belonging to grade 1-2. Other side effects included hematocytopenia, gastrointestinal events and herpes zoster, which could be alleviated or restored to normality after supportive treatments. One patient died of pulmonary infection, respiratory failure and septic shock during the intermittent period of chemotherapy. Conclusion ORR of domestic bortezomibˉbased chemotherapy in treatment of the patients with MM is high, and the incidence of adverse reactions shows no significant increase compared with original drugs.

Objective To investigate the efficacy and safety of maintenance treatment with low-dose decitabine after allogeneic stem cell transplantation (allo-HSCT) for high-risk acute lymphoblastic leukemia (ALL). Methods The data of 10 patients with high-risk ALL who received maintenance therapy with low-dose decitabine after allo-HSCT in the First Affiliated Hospital of Zhengzhou University from July 2016 to March 2018 was collected. The incidence of post-transplant relapse and graft-versus-host disease (GVHD) and the safety of the treatment protocol were analyzed. The cumulative incidence of relapse (CIR) rate, disease-free survival (DFS) rate and overall survival (OS) rate were estimated by Kaplan-Meier method. Results Two patients relapsed and the median relapse time of these 10 patients was 575 days after transplantation. The 1-year CIR, OS and DSF rates were 16.7%, 100.0% and 83.3%, respectively. At the end of follow-up, the DFS time after transplantation of 2 patients with p53 mutation were 23 months and 11 months, respectively. There was no induction or alleviation of GVHD caused by decitabine treatment. Nine patients developed grade Ⅰ-Ⅱmyelosuppression. Three patients had unexplained thrombocytopenia after transplantation and their platelet counts recovered after decitabine treatment. Conclusion Maintenance therapy with low-dose decitabine has low hematologic toxicity without increasing GVHD, which could be a maintenance treatment option to prevent relapse after transplantation for patients with high-risk ALL.

BACKGROUND:For pediatric patients with aplastic anemia in China, it is difficult to find human leucocyte antigen-matched sibling donors that are mostly replaced by parental donors.
OBJECTIVE:To retrospectively analyze the clinical efficacy and safety of parental haploidentical peripheral blood hematopoietic stem cel transplantation in children with relapsed and refractory severe aplastic anemia.
METHODS:Seventeen children with relapsed and refractory severe aplastic anemia who had no matched sibling or unrelated donor and failed to respond to immunosuppressive therapy were subjected to parental haploidentical peripheral blood hematopoietic stem cel transplantation. A conditioning regimen of fludarabine+cyclophosphamide+rabbit anti-human thymocyte immunoglobulin antibody and the triple therapy of methotrexate, cyclosporine A and mycophenolate mofetil were applied to prevent graft-versus-host disease.
RESULTS AND CONCLUSION: (1) Of the 17 children, 16 cases (94%) reached hematopoietic reconstitution, and the median time of neutrophils≥ 0.5×109/L and platelets≥ 20×109/L was 13 (11-15) days and 17 (12-28) days, respectively. (2) Incidence of acute graft-versus-host disease was 47% (8 of 17 cases), including 29% (5/17) of grades I-II and 18% (3/17) of grades III-IV. Incidence of chronic graft-versus-host disease was 41% (7/17). (3) With a median folow-up duration of 268 (43-753) days, the overal survival rate was 70.6% (12/17). Five dead cases (29%) belonged to transplantation-related death, including one case of fungal skin infections, one case of graft-versus-host disease, three cases of severe lung infection. No relapse case was reported. These findings indicate that if there are no matched sibling or unrelated donors and the immunosuppression effect is poor, parental haploidentical peripheral blood hematopoietic stem cel transplantation is a safe and effective salvage treatment for children with relapsed and refractory severe aplastic anemia.

Remarkable achievements have been made for lymphocyte infusion of lymphoma and leukemia, especially of lymphoproliferative disease within twenty-first century. The donor lymphocyte infusion or mobilized donor lymphocyte infusion (DLI/DSI) offer an opportunity of second remission for relapse patients post-transplantation. Cytokine-induced killer/DC cytokine-induced killer play an anti-tumor activity beyond non-MHC restricted. Cytotoxic lymphocyte infusion activated by synthetic tumor antigen produces targeted effects of anti-tumor. Transgenic CTL of anti-tumor TCR has brought the dawn in lymphoma and leukemia patients with defective lymphocytes. Maternal lymphocyte infusion play an anti-tumor/viral activity by avoiding the immune barrier of HLA mismatch.