A clonally expanded nodal T-cell population diagnosed as T-cell lymphoma after CAR-T therapy.

Reports of secondary malignancies after chimeric antigen receptor (CAR)-T and possible CAR-T derived malignant transformation necessitate caution. Here we describe a patient with diffuse large B-cell lymphoma who developed new lymphadenopathy 2.5 years after CAR-T in the context of COVID-19 infection with histopathologic features consistent with T-cell lymphoma (TCL).

SWIFT-seq enables comprehensive single-cell transcriptomic profiling of circulating tumor cells in multiple myeloma and its precursors.

Multiple myeloma is a bone marrow (BM) plasma cell malignancy preceded by precursor conditions. BM biopsies are conducted infrequently and can yield inconclusive results due to technical limitations. Profiling circulating tumor cells (CTCs) may enable noninvasive routine clinical assessments but remains challenging.

Secretion of a VEGF-Blocking scFv Enhances CAR T-cell Potency.

Chimeric antigen receptor (CAR) T-cell therapy is an effective treatment strategy for B-cell malignancies; however, its efficacy in solid tumors remains limited. VEGF-targeted drugs are used as antitumor agents to target abnormal tumor vasculature; however, toxicities associated with systemic VEGF blockade limit their maximal therapeutic benefit. Increasing evidence suggests a role for VEGF in the immunosuppressive tumor microenvironment, including through direct induction of T cell-effector dysfunction.

Large-scale dependency and drug screens to characterize the therapeutic vulnerabilities of multiple myeloma with 1q.

The development of targeted therapy for patients with multiple myeloma (MM) is hampered by the low frequency of actionable genetic abnormalities. Gain or amplification of chromosome 1q (1q+) is the most frequent arm-level copy number gain in patients with MM and is associated with higher risk of progression and death despite recent therapeutic advances. Thus, developing targeted therapy for patients with MM with 1q+ stands to benefit a large portion of patients in need of more effective management.

Single-cell RNA sequencing defines distinct disease subtypes and reveals hypo-responsiveness to interferon in asymptomatic Waldenstrom's Macroglobulinemia.

Waldenstrom's Macroglobulinemia (WM) is an IgM-secreting bone marrow (BM) lymphoma that is preceded by an asymptomatic state (AWM). To dissect tumor-intrinsic and immune mechanisms of progression, we perform single-cell RNA-sequencing on 294,206 BM tumor and immune cells from 30 patients with AWM/WM, 26 patients with Smoldering Myeloma, and 23 healthy donors. Despite their early stage, patients with AWM present extensive immune dysregulation, including in normal B cells, with disease-specific immune hallmarks.

Single-cell dynamics of breakthrough toxicities after anakinra prophylaxis for axicabtagene ciloleucel in lymphoma.

Chimeric antigen receptor (CAR) T-cell (CAR-T) therapy is limited by cytokine release syndrome (CRS) and neurotoxicity (NT). We sought to use once-daily prophylactic anakinra, an interleukin-1 (IL-1) receptor antagonist, to prevent CRS/NT that would require hospitalization (grade ≥2) in patients receiving axicabtagene ciloleucel for large-cell lymphoma, with the goal of facilitating outpatient therapy and management. Our study, in line with others, demonstrates that once-daily prophylactic anakinra is insufficient to prevent the development of toxicities that would require hospitalization in most patients.

Comparative analysis of Bcl-2 family protein overexpression in CAR T cells alone and in combination with BH3 mimetics.

Approximately 50% of patients with hematologic malignancies relapse after chimeric antigen receptor (CAR) T cell treatment; mechanisms of failure include loss of CAR T persistence and tumor resistance to apoptosis. We hypothesized that both of these challenges could potentially be overcome by overexpressing one or more of the Bcl-2 family proteins in CAR T cells to reduce their susceptibility to apoptosis, both alone and in the presence of BH3 mimetics, which can be used to activate apoptotic machinery in malignant cells. We comprehensively investigated overexpression of different Bcl-2 family proteins in CAR T cells with different signaling domains as well as in different tumor types.

Phase 1 study of CAR-37 T cells in patients with relapsed or refractory CD37+ lymphoid malignancies.

We report a first-in-human clinical trial using chimeric antigen receptor (CAR) T cells targeting CD37, an antigen highly expressed in B- and T-cell malignancies. Five patients with relapsed or refractory CD37+ lymphoid malignancies were enrolled and infused with autologous CAR-37 T cells. CAR-37 T cells expanded in the peripheral blood of all patients and, at peak, comprised >94% of the total lymphocytes in 4 of 5 patients.

Understanding Mechanisms of Response to CAR T-cell Therapy through Single-Cell Sequencing: Insights and Challenges.

Single-cell RNA sequencing has emerged as a powerful technique to understand the molecular features of chimeric antigen receptor (CAR) T cells that associate with clinical outcomes. Here we discuss the common themes that have emerged from across single-cell studies of CAR T-cell therapy, and summarize the challenges in interpreting this complex data type.

Latent human herpesvirus 6 is reactivated in CAR T cells.

Cell therapies have yielded durable clinical benefits for patients with cancer, but the risks associated with the development of therapies from manipulated human cells are understudied. For example, we lack a comprehensive understanding of the mechanisms of toxicities observed in patients receiving T cell therapies, including recent reports of encephalitis caused by reactivation of human herpesvirus 6 (HHV-6). Here, through petabase-scale viral genomics mining, we examine the landscape of human latent viral reactivation and demonstrate that HHV-6B can become reactivated in cultures of human CD4 T cells.

Single cell characterization of myeloma and its precursor conditions reveals transcriptional signatures of early tumorigenesis.

Multiple myeloma is a plasma cell malignancy almost always preceded by precursor conditions, but low tumor burden of these early stages has hindered the study of their molecular programs through bulk sequencing technologies. Here, we generate and analyze single cell RNA-sequencing of plasma cells from 26 patients at varying disease stages and 9 healthy donors. In silico dissection and comparison of normal and transformed plasma cells from the same bone marrow biopsy enables discovery of patient-specific transcriptional changes.

Distinct cellular dynamics associated with response to CAR-T therapy for refractory B cell lymphoma.

Chimeric antigen receptor (CAR)-T cell therapy has revolutionized the treatment of hematologic malignancies. Approximately half of patients with refractory large B cell lymphomas achieve durable responses from CD19-targeting CAR-T treatment; however, failure mechanisms are identified in only a fraction of cases. To gain new insights into the basis of clinical response, we performed single-cell transcriptome sequencing of 105 pretreatment and post-treatment peripheral blood mononuclear cell samples, and infusion products collected from 32 individuals with large B cell lymphoma treated with either of two CD19 CAR-T products: axicabtagene ciloleucel (axi-cel) or tisagenlecleucel (tisa-cel).

CAR T cell killing requires the IFNγR pathway in solid but not liquid tumours.

Chimeric antigen receptor (CAR) therapy has had a transformative effect on the treatment of haematologic malignancies, but it has shown limited efficacy against solid tumours. Solid tumours may have cell-intrinsic resistance mechanisms to CAR T cell cytotoxicity. Here, to systematically identify potential resistance pathways in an unbiased manner, we conducted a genome-wide CRISPR knockout screen in glioblastoma, a disease in which CAR T cells have had limited efficacy.

Designing sensitive viral diagnostics with machine learning.

Design of nucleic acid-based viral diagnostics typically follows heuristic rules and, to contend with viral variation, focuses on a genome's conserved regions. A design process could, instead, directly optimize diagnostic effectiveness using a learned model of sensitivity for targets and their variants. Toward that goal, we screen 19,209 diagnostic-target pairs, concentrated on CRISPR-based diagnostics, and train a deep neural network to accurately predict diagnostic readout.

A post-transcriptional program of chemoresistance by AU-rich elements and TTP in quiescent leukemic cells.

Background: Quiescence (G0) is a transient, cell cycle-arrested state. By entering G0, cancer cells survive unfavorable conditions such as chemotherapy and cause relapse. While G0 cells have been studied at the transcriptome level, how post-transcriptional regulation contributes to their chemoresistance remains unknown.

The repertoire of mutational signatures in human cancer.

Somatic mutations in cancer genomes are caused by multiple mutational processes, each of which generates a characteristic mutational signature. Here, as part of the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA), we characterized mutational signatures using 84,729,690 somatic mutations from 4,645 whole-genome and 19,184 exome sequences that encompass most types of cancer. We identified 49 single-base-substitution, 11 doublet-base-substitution, 4 clustered-base-substitution and 17 small insertion-and-deletion signatures.

Analyses of non-coding somatic drivers in 2,658 cancer whole genomes.

The discovery of drivers of cancer has traditionally focused on protein-coding genes. Here we present analyses of driver point mutations and structural variants in non-coding regions across 2,658 genomes from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). For point mutations, we developed a statistically rigorous strategy for combining significance levels from multiple methods of driver discovery that overcomes the limitations of individual methods.