Naturally occurring T cell mutations enhance engineered T cell therapies

The underlying mechanism of chimeric antigen receptor (CAR)-T cell therapy triggering secondary T-cell cancers: Mystery of the Sphinx?

The U.S. Food and Drug Administration (FDA) has reported cases of T-cell malignancies, including CAR-positive lymphomas, in patients receiving B cell maturation antigen (BCMA)- or CD19-targeted autologous CAR-T cell immunotherapy. These reports were derived from clinical trials and/or post-marketing adverse event data. This finding has attracted widespread attention. Therefore, it is essential to explore the potential mechanisms by which chimeric antigen receptor (CAR)-T cell therapy triggers secondary T-cell cancers to further guarantee the safety of CAR-T cell therapy.

Future perspectives on engineered T cells for cancer

Chimeric antigen receptor (CAR) T cell therapy has emerged as a revolutionary treatment for hematological malignancies, but its adaptation to solid tumors is impeded by multiple challenges, particularly T cell dysfunction and exhaustion. The heterogeneity and inhospitableness of the solid tumor microenvironment (TME) contribute to diminished CAR T cell efficacy exhibited by reduced cytotoxicity, proliferation, cytokine secretion, and the upregulation of inhibitory receptors, similar to the phenotype of tumor-infiltrating lymphocytes (TILs). In this review, we highlight recent advances in T cell therapy for solid tumors, particularly brain cancer. Innovative strategies, including locoregional delivery and 'armoring' CAR T cells with cytokines such as interleukin (IL)-18, are under investigation to improve efficacy and safety. We also highlight emerging issues with toxicity management of CAR T cell adverse events. This review discusses the obstacles associated with CAR T cell therapy in the context of solid tumors and outlines current and future strategies to overcome these challenges.

The Fate(s) of CAR T-Cell Therapy: Navigating the Risks of CAR+ T-Cell Malignancy

The introduction of chimeric antigen receptor (CAR) T-cell therapy represents a landmark advancement in treating resistant forms of cancer such as leukemia, lymphoma, and myeloma. However, concerns about long-term safety have emerged following an FDA investigation into reports of second primary malignancies (SPM) after CAR-T cell treatment. This review offers a thorough examination of how genetically modified T cells might transform into CAR+ SPM. It explores genetic and molecular pathways leading to T-cell lymphomagenesis, the balance between CAR T-cell persistence, stemness, and oncogenic risk, and the trade-off of T-cell exhaustion, which may limit therapy efficacy but potentially reduce lymphomagenesis risk. Significance: An FDA probe into 22 cases of second primary T-cell malignancies following CAR T-cell therapy stresses the need to investigate their origins. Few may arise from preexisting genetic and epigenetic alterations and those introduced during therapeutic engineering. Technological advances, regulatory oversight, and patient monitoring are essential to mitigate potential risks.

Engineered CARD11-PIK3R3 T-cell therapies as weapons of cancer mass destruction

Garcia et al. discover a novel immunotherapy approach by engineering naturally occurring mutations in therapeutic T cells to strongly elevate anti-tumor activity. The authors identify a gene fusion, CARD11-PIK3R3, to increase activator protein 1 and nuclear factor-κB signaling, interleukin-2 production, and tumor death in vitro and in vivo .

Somatic mutations in FAS pathway increase hemophagocytic lymphohistiocytosis risk in patients with T- and/or NK-cell lymphoma

ABSTRACT

Although significant progress has been made in understanding the genetic basis of primary hemophagocytic lymphohistiocytosis (HLH), the pathogenesis of secondary HLH, the more prevalent form, remains unclear. Among the various conditions giving rise to secondary HLH, HLH in patients with lymphoma (HLH-L) accounts for a substantial proportion. In this study, we investigated the role of somatic mutations in the pathogenesis of HLH-L in a cohort of patients with T- and/or natural killer-cell lymphoma. We identified a 3-time higher frequency of mutations in FAS pathway in patients with HLH-L. Patients harboring these mutations had a 5-time increased HLH-L risk. These mutations were independently associated with inferior outcome. Hence, our study demonstrates the association between somatic mutations in FAS pathway and HLH-L. Further studies are warranted on the mechanistic role of these mutations in HLH-L.

Small molecule-regulated switches to provide functional control of CAR T cells within the patient

INTRODUCTION

CAR T cells have generated great excitement due to their remarkable clinical response rates in selected hematologic malignancies. However, these engineered immune cells are living drugs which are hard to control after administration.

AREAS COVERED

We discuss small molecule-regulated switch systems which can potentially be used to control CAR T cell function within the patient, as well as the most important obstacles in the CAR T cell field, which might be overcome with those switch systems.

EXPERT OPINION

There is an urgent need to develop advanced switch systems. Once available, we expect that they will open up new avenues for future CAR T cell generations.

Unveiling a novel fusion gene enhances CAR T cell therapy for solid tumors

The efficacy of Adoptive Cell Transfer Therapy (ACT) in combating hematological tumors has been well-documented, yet its application to solid tumors faces formidable hurdles, chief among them being the suboptimal therapeutic response and the immunosuppressive milieu within the tumor microenvironment (TME). Recently, Garcia, J. et al. present compelling findings shedding light on potential breakthroughs in this domain. Their investigation reveals the pronounced augmentation of anti-tumor activity in CAR T cells through the introduction of a T cell neoplasm fusion gene, CARD11-PIK3R3. The incorporation of this gene into engineered T cell therapy holds promise as a formidable tool in the arsenal of cancer immunotherapy. The innovative strategy outlined not only mitigates the requirement for high doses of CAR T cells but also enhances tumor control while exhibiting encouraging safety profiles. The exploration of the CARD11-PIK3R3 fusion gene represents an advancement in our approach to bolstering the anti-tumor efficacy of immunotherapeutic interventions. Nonetheless, the imperative for further inquiry to ascertain its transfection efficiency and long-term safety cannot be overstated. Nevertheless, this seminal investigation offers a beacon of hope in surmounting the formidable treatment impediments posed by solid tumors, paving the way for a transformative era in cancer therapeutics.

A Roadmap of CAR-T-Cell Therapy in Glioblastoma: Challenges and Future Perspectives

Glioblastoma (GBM) is the most common primary malignant brain tumor, with a median overall survival of less than 2 years and a nearly 100% mortality rate under standard therapy that consists of surgery followed by combined radiochemotherapy. Therefore, new therapeutic strategies are urgently needed. The success of chimeric antigen receptor (CAR) T cells in hematological cancers has prompted preclinical and clinical investigations into CAR-T-cell treatment for GBM. However, recent trials have not demonstrated any major success. Here, we delineate existing challenges impeding the effectiveness of CAR-T-cell therapy for GBM, encompassing the cold (immunosuppressive) microenvironment, tumor heterogeneity, T-cell exhaustion, local and systemic immunosuppression, and the immune privilege inherent to the central nervous system (CNS) parenchyma. Additionally, we deliberate on the progress made in developing next-generation CAR-T cells and novel innovative approaches, such as low-intensity pulsed focused ultrasound, aimed at surmounting current roadblocks in GBM CAR-T-cell therapy.