Finding new lanes: Chimeric antigen receptor (CAR) T-cells for myeloid leukemia

Broadening the horizon: potential applications of CAR-T cells beyond current indications

Engineering immune cells to treat hematological malignancies has been a major focus of research since the first resounding successes of CAR-T-cell therapies in B-ALL. Several diseases can now be treated in highly therapy-refractory or relapsed conditions. Currently, a number of CD19- or BCMA-specific CAR-T-cell therapies are approved for acute lymphoblastic leukemia (ALL), diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma (MCL), multiple myeloma (MM), and follicular lymphoma (FL). The implementation of these therapies has significantly improved patient outcome and survival even in cases with previously very poor prognosis. In this comprehensive review, we present the current state of research, recent innovations, and the applications of CAR-T-cell therapy in a selected group of hematologic malignancies. We focus on B- and T-cell malignancies, including the entities of cutaneous and peripheral T-cell lymphoma (T-ALL, PTCL, CTCL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), chronic lymphocytic leukemia (CLL), classical Hodgkin-Lymphoma (HL), Burkitt-Lymphoma (BL), hairy cell leukemia (HCL), and Waldenström's macroglobulinemia (WM). While these diseases are highly heterogenous, we highlight several similarly used approaches (combination with established therapeutics, target depletion on healthy cells), targets used in multiple diseases (CD30, CD38, TRBC1/2), and unique features that require individualized approaches. Furthermore, we focus on current limitations of CAR-T-cell therapy in individual diseases and entities such as immunocompromising tumor microenvironment (TME), risk of on-target-off-tumor effects, and differences in the occurrence of adverse events. Finally, we present an outlook into novel innovations in CAR-T-cell engineering like the use of artificial intelligence and the future role of CAR-T cells in therapy regimens in everyday clinical practice.

Transcriptional states of CAR-T infusion relate to neurotoxicity – lessons from high-resolution single-cell SOM expression portraying

Anti-CD19 CAR-T cell immunotherapy is a hopeful treatment option for patients with B cell lymphomas, however it copes with partly severe adverse effects like neurotoxicity. Single-cell resolved molecular data sets in combination with clinical parametrization allow for comprehensive characterization of cellular subpopulations, their transcriptomic states, and their relation to the adverse effects. We here present a re-analysis of single-cell RNA sequencing data of 24 patients comprising more than 130,000 cells with focus on cellular states and their association to immune cell related neurotoxicity. For this, we developed a single-cell data portraying workflow to disentangle the transcriptional state space with single-cell resolution and its analysis in terms of modularly-composed cellular programs. We demonstrated capabilities of single-cell data portraying to disentangle transcriptional states using intuitive visualization, functional mining, molecular cell stratification, and variability analyses. Our analysis revealed that the T cell composition of the patient’s infusion product as well as the spectrum of their transcriptional states of cells derived from patients with low ICANS grade do not markedly differ from those of cells from high ICANS patients, while the relative abundancies, particularly that of cycling cells, of LAG3-mediated exhaustion and of CAR positive cells, vary. Our study provides molecular details of the transcriptomic landscape with possible impact to overcome neurotoxicity.

Therapeutic potential of 1,2,3-triazole hybrids for leukemia treatment

Leukemia, a hematological malignancy originating from the bone marrow, is the principal cancer of childhood. In recent decades, improved remission rates and survival of patients with leukemia have been achieved due to significant breakthroughs in the treatment. However, chemoresistance and relapse are common, creating an urgent need for the search for novel pharmaceutical interventions. 1,2,3-Triazole is one of the most fascinating pharmacophores in the discovery of new drugs, and several 1,2,3-triazole derivatives have already been used in clinics or are under clinical evaluation for the treatment of cancers. In particular, 1,2,3-triazole hybrids could suppress tumor proliferation, invasion, and metastasis by inhibiting enzymes, proteins, and receptors in cancer cells, revealing their potential as putative antileukemic agents. This review covers the recent advances regarding the 1,2,3-triazole hybrids with potential antileukemic activity, focusing on the chemical structures, structure-activity relationship, and mechanisms of action, covering articles published from January 2017 to January 2022.

Finding new lanes: Chimeric antigen receptor (CAR) T-cells for myeloid leukemia

BACKGROUND

Myeloid leukemia represents a heterogeneous group of cancers of blood and bone marrow which arise from clonal expansion of hematopoietic myeloid lineage cells. Acute myeloid leukemia (AML) has traditionally been treated with multi-agent chemotherapy, but conventional therapies have not improved the long-term survival for decades. Chronic myeloid leukemia (CML) is an indolent disease which requires lifelong treatment, is associated with significant side effects, and carries a risk of progression to potentially lethal blast crises.

RECENT FINDINGS

Recent advances in molecular biology, virology, and immunology have enabled researchers to grow and modify T lymphocytes ex-vivo. Chimeric antigen receptor (CAR) T-cell therapy has been shown to specifically target cells of lymphoid lineage and induce remission in acute lymphoblastic leukemia (ALL) patients. While the success of CAR T-cells against ALL is considered a defining moment in modern oncology, similar efficacy against myeloid leukemia cells remains elusive. Over the past 10 years, numerous CAR T-cells have been developed that can target novel myeloid antigens, and many clinical trials are finally starting to yield encouraging results. In this review, we present the recent advances in this field and discuss strategies for future development of myeloid targeting CAR T-cell therapy.

CONCLUSIONS

The field of CAR T-cell therapy has rapidly evolved over the past few years. It represents a radically new approach towards cancers, and with continued refinement it may become a viable therapeutic option for patients of acute and chronic myeloid leukemia.