Acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) are usually associated with poor outcomes, especially in high‐risk AML/MDS. Allogeneic hematopoietic stem cell transplantation ...(allo‐HSCT) is the only curative option for patients suffering from high‐risk AML/MDS. However, many patients relapse after allo‐HSCT. Novel therapy to prevent relapse is urgently needed. Both the BCL‐2 inhibitor venetoclax (VEN) and the hypomethylating agent decitabine (DEC) possess significant antitumor activity effects against AML/MDS. Administration of DEC has been shown to ameliorate graft‐versus‐host disease (GVHD) and boost the graft‐versus‐leukemia (GVL) effect post‐transplantation. We therefore conducted a prospective study (ChiCTR1900025374) to examine the tolerability and efficacy of a maintenance therapy of low‐dose decitabine (LDEC) plus VEN to prevent relapse after allo‐HSCT for high‐risk AML/MDS patients. Twenty patients with high‐risk AML (n = 17) or high‐risk MDS (n = 3) post‐transplantation were recruited. Approximately day 100 post‐transplantation, all patients received LDEC (15 mg/m2 for 3 d) followed by VEN (200 mg) on d 1‐21. The cycle interval was 2 mo, and there was 10 cycles. The primary end points of this study were rates of overall survival (OS) and event‐free survival (EFS). The secondary endpoints included adverse events (AEs), cumulative incidence of relapse (CIR), nonrelapse mortality (NRM), incidences of acute GVHD (aGVHD) and chronic GVHD (cGVHD), and incidences of viral infection after allo‐HSCT. Survival outcomes were assessed using Kaplan‐Meier analysis. The median follow‐up was 598 (149‐1072) d. Two patients relapsed, 1 died, and 1 is still alive after the second transplant. The 2‐y OS and EFS rates were 85.2% and 84.7%, respectively. The median 2‐y EFS time was 525 (149‐1072) d, and 17 patients still had EFS and were alive at the time of this writing. The most common AEs were neutropenia, anemia, thrombocytopenia, neutropenic fever, and fatigue. Grade 2 or 3 AEs were observed in 35% (7/20) and 20% (4/20) of the patients, respectively. No grade >3 AEs were observed. aGVHD (any grade) and cGVHD (limited or extensive) occurred in 55% and 20% of patients, respectively. We conclude that LDEC + VEN can be administered safely after allo‐HSCT with no evidence of an increased incidence of GVHD, and this combination decreases the relapse rate in high‐risk AML/MDS patients. This novel maintenance therapy may be a promising way to prevent relapse in high‐risk AML/MDS patients.
The results of the current study suggest that maintenance treatment with LDEC combined with VEN introduced nearly 3 mo after allo‐HSCT is efficacious, with an acceptable toxicity profile and impressive long‐term disease control.
Chimeric antigen receptor (CAR) T cells are emerging as a novel treatment for patients with refractory/relapsed B-cell non-Hodgkin lymphoma (B-NHL), and combination with PD1 inhibitors may further ...improve the efficacy of anti-CD19 CAR (CD19 CAR)-T cells in the treatment of lymphomas. In a single-center study, we evaluated the safety and efficacy of a combination therapy with CD19 CAR-T cells and an anti-PD-1 antibody (nivolumab) in patients with relapsed/refractory B-NHL. A total of 11 patients with refractory/relapsed B-NHL were recruited and subsequently received CD19 CAR-T cells and nivolumab. The primary end points were safety and feasibility. The infusions were safe, and no dose-limiting toxicities occurred. Grade 1 or 2 cytokine release syndrome (CRS) was observed in 25% (3/11) and 50% (6/11) of the patients, respectively, and only one patient (1/11) experienced neurotoxicity. The objective response rate (ORR) and complete response (CR) rate were 81.81% (9/11) and 45.45% (5/11), respectively. The median follow-up time was 6 (1~15) months. The median progression-free survival (PFS) time was 6 months (1~14 months), and 3 patients continued to have a response at the time of this writing. Our study demonstrated that the combination of CD19 CAR-T cells and nivolumab was feasible and safe and mediated potent anti-lymphoma activity, which should be examined further in prospective clinical trials in refractory/relapsed B-NHL.
Chimeric antigen receptor T cell (CAR-T cell) therapy is a relatively new, effective, and rapidly evolving therapeutic for adoptive immunotherapies. Although it has achieved remarkable effect in ...hematological malignancies, there are some problems that remain to be resolved. For example, there are high recurrence rates and poor efficacy in solid tumors. In this review, we first briefly describe the metabolic re-editing of T cells and the changes in metabolism during the preparation of CAR-T cells. Furthermore, we summarize the latest developments and newest strategies to improve the metabolic adaptability and antitumor activity of CAR-T cells in vitro and in vivo.
Stem cells play critical roles both in the development of cancer and therapy resistance. Although mesenchymal stem cells (MSCs) can actively migrate to tumor sites, their impact on chimeric antigen ...receptor modified T cell (CAR-T) immunotherapy has been little addressed. Using an in vitro cell co-culture model including lymphoma cells and macrophages, here we report that CAR-T cell-mediated cytotoxicity was significantly inhibited in the presence of MSCs. MSCs caused an increase of CD4
T cells and Treg cells but a decrease of CD8
T cells. In addition, MSCs stimulated the expression of indoleamine 2,3-dioxygenase and programmed cell death-ligand 1 which contributes to the immune-suppressive function of tumors. Moreover, MSCs suppressed key components of the NLRP3 inflammasome by modulating mitochondrial reactive oxygen species release. Interestingly, all these suppressive events hindering CAR-T efficacy could be abrogated if the stanniocalcin-1 (STC1) gene, which encodes the glycoprotein hormone STC-1, was knockdown in MSC. Using xenograft mice, we confirmed that CAR-T function could also be inhibited by MSC in vivo, and STC1 played a critical role. These data revealed a novel function of MSC and STC-1 in suppressing CAR-T efficacy, which should be considered in cancer therapy and may also have potential applications in controlling the toxicity arising from the excessive immune response.
Relapsed or refractory (R/R) acute myeloid leukemia (AML) has a poor prognosis. In this study, we evaluated chimeric antigen receptor (CAR) T cell therapy targeting CLL-1 in adults with R/R AML ...patients. Patients received conditioning chemotherapy with cyclophosphamide (500 mg/m.sup.2) and fludarabine (30 mg/m.sup.2) for 3 days and an infusion of a dose of 1-2 x 10.sup.6 CAR-T cells/kg. The incidence of dose-limiting toxicity was the primary endpoint. Ten patients were treated, and all developed cytokine release syndrome (CRS); 4 cases were low-grade, while the remaining 6 were considered high-grade CRS. No patient developed CAR-T cell-related encephalopathy syndrome (CRES). Severe pancytopenia occurred in all patients. Two patients died of severe infection due to chronic agranulocytosis. The complete response (CR)/CR with incomplete hematologic recovery (CRi) rate was 70% (n = 7/10). The median follow-up time was 173 days (15-488), and 6 patients were alive at the end of the last follow-up. CAR-T cells showed peak expansion within 2 weeks. Notably, CLL-1 is also highly expressed in normal granulocytes, so bridging hematopoietic stem cell transplantation (HSCT) may be a viable strategy to rescue long-term agranulocytosis due to off-target toxicity. In conclusion, this study is the first to demonstrate the positive efficacy and tolerable safety of CLL-1 CAR-T cell therapy in adult R/R AML. Keywords: Chimeric antigen receptor, Acute myeloid leukemia, C-type lectin-like molecule 1
Objective
To evaluate the efficacy of combined rapid on-site evaluation of cytology (ROSE), ultrathin bronchoscopy, virtual bronchoscopic navigation, radial endobronchial ultrasound (EBUS), and ...metagenomic next-generation sequencing (mNGS) for diagnosis of peripheral pulmonary infectious lesions.
Methods
Specimens from patients with peripheral lung infection were obtained by transbronchial lung biopsy (TBLB) and bronchoalveolar lavage (BAL), and mNGS was used to detect pathogenic microorganisms. The sensitivity and specificity of mNGS were compared between TBLB tissue and BAL fluid.
Results
The most common pathogens of pulmonary infectious lesions in this study were Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii. The specificity of mNGS was higher in TBLB tissue than in BAL fluid, but mNGS of BAL fluid had higher sensitivity.
Conclusions
The combination of ROSE, ultrathin bronchoscopy, virtual bronchoscopic navigation, radial EBUS, and mNGS technology yielded high efficacy for the diagnosis of peripheral pulmonary infectious lesions. TBLB and BAL specimens have respective advantages in specificity and sensitivity for mNGS analysis.
Opinion statement
Although chimeric antigen receptor T cell immunotherapy has been successfully applied in patients with hematological malignancies, several obstacles still need to be overcome, such ...as high relapse rates and side effects. Overcoming the limitations of CAR-T cell therapy and boosting the efficacy of CAR-T cell therapy are urgent issues that must be addressed. The exploration of small-molecule compounds in combination with CAR-T cell therapies has achieved promising success in pre-clinical and clinical studies in recent years. Protein kinase inhibitors, demethylating drugs, HDAC inhibitors, PI3K inhibitors, immunomodulatory drugs, Akt inhibitors, mTOR inhibitors, and Bcl-2 inhibitors exhibited potential synergy in combination with CAR-T cell therapy. In this review, we will discuss the recent application of these combination therapies for improved outcomes of CAR-T cell therapy.
The high expression of CD7 targets in T-cell acute lymphoblastic leukemia (T-ALL) and T-lymphoma has attracted considerable attention from researchers. However, because CD7 chimeric antigen receptor ...(CAR) T-cells undergo fratricide, CD7 CAR T-cells develop an exhaustion phenotype that impairs the effect of CAR T-cells. There have been significant breakthroughs in CD7-targeted CAR T-cell therapy in the past few years. The advent of gene editing, protein blockers, and other approaches has effectively overcome the adverse effects of conventional methods of CD7 CAR T-cells. This review, in conjunction with recent advances in the 64
annual meeting of the American Society of Hematology (ASH), provides a summary of the meaningful achievements in CD7 CAR T-cell generations and clinical trials over the last few years.
B cell lymphoma 2 (BCL-2) family proteins play an important role in intrinsic apoptosis. Overexpression of BCL-2 proteins in acute myeloid leukemia can circumvent resistance to apoptosis and ...chemotherapy. Considering this effect, the exploration of anti-apoptotic BCL-2 inhibitors is considered to have tremendous potential for the discovery of novel pharmacological modulators in cancer. This review outlines the impact of BCL-2 family proteins on intrinsic apoptosis and the development of acute myeloid leukemia (AML). Furthermore, we will also review the new combination therapy with venetoclax that overcomes resistance to venetoclax and discuss biomarkers of treatment response identified in early-phase clinical trials.
Opinion statement
Chimeric antigen receptor (CAR) cell therapy offers patients with hematological malignancies a new therapeutic option. Traditionally, autologous T cells are used to generate CAR ...designed T cells for each patient. However, this method has several drawbacks, the development of allogeneic CAR cell therapy would be a promising breakthrough that could address several of these limitations. From the clinical trials that have published data, the efficacy of allogeneic CAR cell therapy did not meet the expectations. Because of the host-versus-graft (HvG) effect, allogeneic CAR cells are eliminated by the host, resulting in short-term persistence of allogeneic CAR cells and poor efficacy. It is critical to solve the HvG effect of allogeneic CAR cells. The current commonly used methods are suppressing the host’s immune system, using HLA-matched homozygous donors, reducing the expression of HLA, targeting alloreactive lymphocytes and eliminating anti-CAR activities. In this review, we will focus on the HvG effect of the “off-the-shelf” allogeneic CAR cell therapy, especially its mechanism and current methods to solve this problem and summarize relevant clinical trial data.
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