Mechanisms of resistance to CAR T cell therapy

Overcoming antigen loss in CAR T therapy with Vγ9Vδ2 CAR T-cells

Background

Vγ9Vδ2 T-cells demonstrate potent antitumor activity in vitro but, despite successful safety studies, the clinical benefit of Vγ9Vδ2 in adoptive cell therapy has been limited. One approach to enhance the therapeutic potential of Vγ9Vδ2 T-cells while maintaining their safety profile is genetic engineering to express a chimeric antigen receptor (CAR). Vγ9Vδ2 CAR T-cells retain the ability to target tumor cells even after target antigen loss, a major cause of CAR treatment relapse.

Methods

Vγ9Vδ2 T-cells were expanded from peripheral blood mononuclear cells in the presence of high levels of interleukin 2 (IL-2) or IL-2 in combination with IL-15. Cells were then virally transduced with a CD19-directed CAR and underwent antigen-specific stimulation to enrich CAR-expressing cells.

Results

Vγ9Vδ2 CAR T-cells showed similar cytotoxic activity to conventional αβ-CAR T-cells against CD19-positive tumor cells. They demonstrated superior responses against CD19-negative tumor cells, however, particularly when IL-15 was included during expansion. This enhanced function was further confirmed in co-culture assays with mixed CD19-positive and CD19-negative tumor populations, simulating antigen loss.

Conclusions

Vγ9Vδ2 CAR T-cell therapy presents a promising strategy for B-cell malignancies, offering sustained antitumor activity even after antigen loss. This approach may help overcome a major limitation of conventional CAR T-cell therapy, potentially improving clinical outcomes.

CD22 CAR-T cells secreting CD19 T-cell engagers for improved control of B-cell acute lymphoblastic leukemia progression

BACKGROUND

CD19-directed cancer immunotherapies, based on engineered T cells bearing chimeric antigen receptors (CARs, CAR-T cells) or the systemic administration of bispecific T cell-engaging (TCE) antibodies, have shown impressive clinical responses in relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL). However, more than half of patients relapse after CAR-T or TCE therapy, with antigen escape or lineage switching accounting for one-third of disease recurrences. To minimize tumor escape, dual-targeting CAR-T cell therapies simultaneously targeting CD19 and CD22 have been developed and validated both preclinically and clinically.

METHODS

We have generated the first dual-targeting strategy for B-cell malignancies based on CD22 CAR-T cells secreting an anti-CD19 TCE antibody (CAR-STAb-T) and conducted a comprehensive preclinical characterization comparing its therapeutic potential in B-ALL with that of previously validated dual-targeting CD19/CD22 tandem CAR cells (TanCAR-T cells) and co-administration of two single-targeting CD19 and CD22 CAR-T cells (pooled CAR-T cells).

RESULTS

We demonstrate that CAR-STAb-T cells efficiently redirect bystander T cells, resulting in higher cytotoxicity of B-ALL cells than dual-targeting CAR-T cells at limiting effector:target ratios. Furthermore, when antigen loss was replicated in a heterogeneous B-ALL cell model, CAR-STAb T cells induced more potent and effective cytotoxic responses than dual-targeting CAR-T cells in both short- and long-term co-culture assays, reducing the risk of CD19-positive leukemia escape. In vivo, CAR-STAb-T cells also controlled leukemia progression more efficiently than dual-targeting CAR-T cells in patient-derived xenograft mouse models under T cell-limiting conditions.

CONCLUSIONS

CD22 CAR-T cells secreting CD19 T-cell engagers show an enhanced control of B-ALL progression compared with CD19/CD22 dual CAR-based therapies, supporting their potential for clinical testing.

IKAROS levels are associated with antigen escape in CD19- and CD22-targeted therapies for B-cell malignancies

Antigen escape relapse is a major challenge in targeted immunotherapies, including CD19- and CD22-directed chimeric antigen receptor (CAR) T-cell for B-cell acute lymphoblastic leukemia (B-ALL). To identify tumor-intrinsic factors driving antigen loss, we perform single-cell analyses on 61 B-ALL patient samples treated with CAR T cells. Here we show that low levels of IKAROS in pro-B-like B-ALL cells before CAR T treatment correlate with antigen escape. IKAROSlow B-ALL cells undergo epigenetic and transcriptional changes that diminish B-cell identity, making them resemble progenitor cells. This shift leads to reduced CD19 and CD22 surface expression. We demonstrate that CD19 and CD22 expression is IKAROS dose-dependent and reversible. Furthermore, IKAROSlow cells exhibit higher resistance to CD19- and CD22-targeted therapies. These findings establish a role for IKAROS as a regulator of antigens targeted by widely used immunotherapies and in the risk of antigen escape relapse, identifying it as a potential prognostic target.

Advancements in molecular imaging for the diagnosis and treatment of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly malignant tumor characterized by poor overall patient survival and prognosis, largely due to challenges in early diagnosis, limited surgical options, and a high propensity for therapy resistance. The integration of various imaging modalities through molecular imaging techniques, particularly multimodal molecular imaging, offers the potential to provide more precise and comprehensive information about the lesion. With advances in nanomedicine, new imaging and drug delivery approaches that allow the development of multifunctional theranostic agents offer opportunities for improving pancreatic cancer treatment using precision oncology. Herein, we review the diagnostic and therapeutic applications of molecular imaging for PDAC and discuss the adoption of multimodal imaging approaches that combine the strengths of different imaging techniques to enhance diagnostic accuracy and therapeutic efficacy. We emphasize the significant role of nanomedicine technology in advancing multimodal molecular imaging and theranostics, and their potential impact on PDAC management. This comprehensive review aims to serve as a valuable reference for researchers and clinicians, offering insights into the current state of molecular imaging in PDAC and outlining future directions for improving early diagnosis, combination therapies, and prognostic evaluations.

Safety and feasibility of 4-1BB co-stimulated CD19-specific CAR-NK cell therapy in refractory/relapsed large B cell lymphoma: a phase 1 trial

Chimeric antigen receptor (CAR)-modified NK (CAR-NK) cells are candidates for next-generation cancer immunotherapies. Here we generated CD19-specific CAR-NK cells with 4-1BB and CD3ζ signaling endo-domains (CD19-BBz CAR-NK) by transduction of cord blood-derived NK cells using baboon envelope pseudotyped lentiviral vectors and demonstrated their antitumor activity in preclinical B cell lymphoma models in female mice. We next conducted a phase 1 dose-escalation trial involving repetitive administration of CAR-NK cells in 8 patients with relapsed/refractory large B cell lymphoma (NCT05472558). Primary end points were safety, maximum tolerated dose, and overall response rate. Secondary end points included duration of response, overall survival, and progression-free survival. No dose-limiting toxicities occurred, and the maximum tolerated dose was not reached. No cases of cytokine release syndrome, neurotoxicity, or graft-versus-host disease were observed. Results showed an overall response rate of 62.5% at day 30, with 4 patients (50%) achieving complete response. The median progression-free survival was 9.5 months, and the median overall survival was not reached. A post hoc exploratory single-cell RNA sequencing analysis revealed molecular features of CAR-NK cells associated with therapeutic efficacy and efficacy-related immune cell interaction networks. This study met the pre-specified end points. In conclusion, CD19-BBz CAR-NK cells were feasible and therapeutically safe, capable of inducing durable response in patients with B cell lymphoma.

T-bet overexpression enhances CAR T cell effector functions and antigen sensitivity

BACKGROUND

T cells modified to express a chimeric antigen receptor (CAR) are successful against B-lineage malignancies but fail to induce durable remissions in up to half of patients and have shown limited efficacy against other types of cancer. Strategies to improve CAR T cell potency and responses to low antigen densities without inducing CAR T cell dysfunction or limiting persistence are necessary to expand durability of remissions.

METHODS

We overexpressed T-bet in human and mouse CAR T cells to mimic exposure to signal 3 cytokines during T cell priming to promote T helper cell 1 (Th1) polarization of CD4+CAR T cells with the goal of enhancing antitumor activity. Using human CAR T cells and xenograft models we interrogated the impact of T-bet overexpression on CAR T cell antitumor activity in vitro and in vivo. We also used a syngeneic murine CAR T cell model to study the impact of T-bet overexpression on long-term persistence and secondary responses to tumor rechallenge.

RESULTS

T-bet overexpression reduced expression of the Th2 cytokine interleukin 4 and promoted polyfunctional production of Th1-associated cytokines in response to CAR stimulation. T-bet overexpression enhanced some effector functions in vitro but did not improve CAR T cell-mediated control of leukemia expressing high levels of antigen in vivo. T-bet overexpression also improved effector function of murine CD19 CAR T cells with no impairment to the persistence or ability of persistent CAR T cells to re-expand and clear a secondary leukemia challenge. Finally, T-bet overexpression promoted enhanced in vitro function against leukemia expressing low levels of CD19, which translated to improved control of CD19lo leukemia in vivo by human C19 CAR T cells containing a 4-1BB costimulatory domain.

CONCLUSIONS

Together, our data demonstrate that T-bet overexpression induces a reduction in Th2 cytokine production, an increase in polyfunctional Th1 cytokine production and enhances 4-1BB CAR T cell activity against cancers expressing low levels of target antigen without promoting a loss in functional CAR T cell persistence.

The 2023 EBMT report on hematopoietic cell transplantation and cellular therapies. Increased use of allogeneic HCT for myeloid malignancies and of CAR-T at the expense of autologous HCT

In 2023, 47,731 HCT (20,485 (42.9%) allogeneic and 27,246 (57.1%) autologous) in 43,902 patients were reported by 696 European centers. 6042 patients received advanced cellular therapies, 4888 of which were CAR-T. Compared to the previous year there was an increase in CAR-T (+52.5%), in allogeneic HCT (+7.8%) but none in autologous HCT (+0.4%). Main indications for allogeneic HCT were myeloid (11,748; 60.7%), lymphoid malignancies (4,850; 25.0%), and non-malignant disorders (2558; 13.2%). Use of allogeneic HCT increased for AML (+12.1%) and for NHL (+11.0%), particularly in T-NHL (+25.6%). Main indications for autologous HCT were lymphomas (7890; 32.2%), PCD (14,271; 58.2%), and solid tumors (1608; 6.6%) with recovering numbers for autoimmune diseases. In patients with allogeneic HCT, the use of sibling donors increased by +1.0%, haploidentical donors by +11.7%, and unrelated donors by +11.1%. Cord blood HCT decreased again by -5.4%. Pediatric HCT activity increased slightly (5455; +0.1%) with differences between allogeneic (4111; -0.5%) and autologous HCT (1344: +1.7%). Use of CAR-T increased to a cumulative total of 13,927 patients including patients treated for autoimmune diseases. Overall, numbers show a complete recovery from the pandemic dip with increased cellular therapy at the expense of autologous HCT. Allogeneic HCT activity focuses on myeloid malignancies.

Charge-based immunoreceptor signalling in health and disease

Immunoreceptors have crucial roles in sensing environmental signals and initiating immune responses to protect the host. Dysregulation of immunoreceptor signalling can therefore lead to a range of diseases, making immunoreceptor-based therapies a promising frontier in biomedicine. A common feature of various immunoreceptors is the basic-residue-rich sequence (BRS), which is a largely unexplored aspect of immunoreceptor signalling. The BRS is typically located in the cytoplasmic juxtamembrane region of immunoreceptors, where it forms dynamic interactions with neighbouring charged molecules to regulate signalling. Loss or gain of the basic residues in an immunoreceptor BRS has been linked to severe human diseases, such as immunodeficiency and autoimmunity. In this Perspective, we describe the role of BRSs in various immunoreceptors, elucidating their signalling mechanisms and biological functions. Furthermore, we highlight pathogenic mutations in immunoreceptor BRSs and discuss the potential of leveraging BRS signalling in engineered T cell-based therapies.

Mathematical modeling unveils the timeline of CAR-T cell therapy and macrophage-mediated cytokine release syndrome

Chimeric antigen receptor (CAR)-T cell therapy holds significant potential for cancer treatment, although disease relapse and cytokine release syndrome (CRS) remain as frequent clinical challenges. To better understand the mechanisms underlying the temporal dynamics of CAR-T cell therapy response and CRS, we developed a novel multi-layer mathematical model incorporating antigen-mediated CAR-T cell expansion, antigen-negative resistance, and macrophage-associated cytokine release. Three key mechanisms of macrophage activation are considered: release of damage-associated molecular patterns, antigen-binding mediated activation, and CD40-CD40L contact. The model accurately describes 25 patient time courses with different responses and IL-6 cytokine kinetics. We successfully link the dynamic shape of the response to interpretable model parameters and investigate the influence of CAR-T cell dose and initial tumor burden on the occurrence of cytokine release and treatment outcome. By disentangling the timeline of macrophage activation, the model identified distinct contributions of each activation mechanism, suggesting the CD40-CD40L axis as a major driver of cytokine release and a clinically feasible target to control the activation process and modulate cytokine peak height. Our multi-layer model provides a comprehensive framework for understanding the complex interactions between CAR-T cells, tumor cells, and macrophages during therapy.

Targeting cardiac fibrosis with Chimeric Antigen Receptor-Engineered Cells

Cardiac fibrosis poses a significant challenge in cardiovascular diseases due to its intricate pathogenesis, and there is currently no standardized and effective treatment approach. The fibrotic process entails the involvement of various cell types and molecular mechanisms, such as fibroblast activation and proliferation, increased collagen synthesis, and extracellular matrix rearrangement. Traditional therapies often fall short in efficacy or carry substantial side effects. However, recent studies have shown that Chimeric Antigen Receptor T (CAR-T) cells can selectively target and eliminate activated cardiac fibroblasts (CFs) in mice, leading to reduced cardiac fibrosis and improved myocardial tissue compliance. This breakthrough presents a new and promising avenue for treating cardiac fibrosis. Currently, CAR-T cell-based therapy for cardiac fibrosis is undergoing animal experimentation, indicating ample scope for enhancement. Future investigations could explore the application of CAR cell therapy in cardiac fibrosis treatment, including the potential of CAR-natural killer (CAR-NK) cells and CAR macrophages (CAR-M), offering novel insights and strategies for combating cardiac fibrosis.

Treatment failure patterns in early versus late introduction of CAR T-cell therapy in large B-cell lymphoma

CD19-directed chimeric antigen receptor T-cell (CAR-T) therapy has recently been approved as second-line treatment for relapsed/refractory large B-cell lymphoma (LBCL). This study compares patterns of disease relapse and progression across patients receiving CAR-T as second-line (early administration) versus third or subsequent lines (late administration). We analyzed 354 patients treated with Axicabtagene ciloleucel (71%) and Lisocabtagene maraleucel (29%); 80 (23%) received early administration, and 274 (77%) late administration. One-year overall survival was higher in the early group (82% [95% CI 72-93] vs. 71% [95% CI 66-77], p = 0.048). However, the survival benefit was not sustained in multivariable Cox regression modeling and propensity score matching. One-year cumulative incidences of relapse were similar (37% [95% CI 24-50] vs. 43% [95% CI 37-49], p = 0.2), as were 1-year progression-free survival probabilities (62% [95% CI 50-76] vs. 50% [95% CI 44-57], p = 0.14). The early group exhibited a favorable toxicity profile, with lower rate of grade ≥2 cytokine release syndrome (26% vs. 39%, p = 0.031) and reduced cumulative incidence of severe neutropenia (41% [95% CI 30-52] vs. 55% [95% CI 49-60], p = 0.027). Our results indicate favorable outcomes with CAR-T irrespective of treatment line. The equivalence in disease control suggests that CAR-T resistance mechanisms persist in LBCL failing first-line therapy.

From molecular design to clinical translation: dual-targeted CAR-T strategies in cancer immunotherapy

The pathogenesis of tumors involves various abnormalities at both the cellular and genetic levels. Chimeric antigen receptor (CAR)-T cell immunotherapy has emerged as a transformative treatment strategy that effectively addresses these challenges. While CAR-T therapy has shown remarkable success in treating hematological malignancies, limitations have been identified, particularly in single antigen-targeting CAR-T therapies. These limitations include antigenic mutation or loss, reduced efficacy against leukemia, and poor results in solid tumors due to factors like low CAR-T cell persistence, limited tumor infiltration, rapid cell exhaustion, the suppressive tumor microenvironment, and heterogeneous tumor antigen expression. In recent years, multi-antigen targeted CAR-T therapies have garnered significant attention for their potential to prevent tumor relapse and progression. This review outlines the fundamental design of dual CAR structures and summarizes the major advancements in both preclinical studies and clinical trials of dual-targeted CAR-T cell therapy, categorized by cancer type. Additionally, it discusses the challenges associated with dual-targeted CAR-T therapy and the strategies to enhance its efficacy and applicability in treating both hematologic and solid tumors. In conclusion, the progress in dual-targeted CAR-T cell therapy presents a promising therapeutic avenue for multiple malignancies, offering insights into future modifications of immunotherapy to advance the field.

Advances in adoptive cell therapies in small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive tumor characterized by early metastasis and resistance to treatment, making it a prime target for therapeutic investigation. The current standard of care for frontline treatment involves a combination of chemotherapeutic agents and immune checkpoint inhibitors (ICIs), though durability of response remains limited. The genetic heterogeneity of SCLC also complicates the development of new therapeutic options. Adoptive cell therapies show promise by targeting specific mutations in order to increase efficacy and minimize toxicity. There has been significant investigation in three therapeutic classes for application towards SCLC: antibody drug conjugates (ADCs), bispecific T-cell engagers (BiTEs), and chimeric antigen receptor (CAR)-T cell therapies. This review summarizes the recent advances and challenges in the development of adoptive cell therapies. Genetic targets such as delta-like ligand 3 (DLL3), trophoblast cell surface antigen 2 (Trop2), B7-H3 (CD276), gangliosides disialoganglioside GD2 (GD2) and ganglioside GM2 (GM2) have been found to be expressed in SCLC, which makes them prime targets for therapy development. While investigated therapies such as rovalpituzumab tesirine (Rova-T) have failed, several insights from these trials have led to the development of compelling new agents such as sacituzumab govitecan (SG), ifinatamab deruxtecan (I-DXd), tarlatamab, and DLL3-targeted CAR-T cells. Advancing development of molecular testing and improving targeted approaches remain integral to pushing forward the progress of adoptive cell therapies in SCLC.

Restoration of LAT activity improves CAR T cell sensitivity and persistence in response to antigen-low acute lymphoblastic leukemia

Chimeric antigen receptor (CAR) T cells induce responses in patients with relapsed/refractory leukemia; however, long-term efficacy is frequently limited by relapse. The inability to target antigen-low cells is an intrinsic vulnerability of second-generation CAR T cells and underlies most relapses following CD22BBz CAR T cell therapy. Here, we interrogate CD22BBz CAR signaling in response to low antigen and find inefficient phosphorylation of the linker for activation of T cells (LAT) limiting downstream signaling. To overcome this, we designed the adjunctive LAT-activating CAR T cell (ALA-CART) platform, pairing a second-generation CAR with a LAT-CAR incorporating the intracellular domain of LAT. ALA-CART cells demonstrate reduced differentiation during manufacturing and increased LAT phosphorylation, MAPK signaling, and AP-1 activity. ALA-CART cells show improved cytotoxicity, proliferation, persistence, and efficacy against antigen-low leukemias that were refractory to clinically active CD22BBz CAR T cells. Restoration of LAT signaling through the ALA-CART platform represents a promising strategy for overcoming multiple mechanisms of CAR T cell failure.

Elevated CD10- neutrophils correlate with non-response and poor prognosis of CD19 CAR T-cell therapy for B-cell acute lymphoblastic leukemia

BACKGROUND

The primary challenges in CD19-specific chimeric antigen receptor T-cell (CD19 CAR T) therapy for patients with refractory/relapsed B-cell acute lymphoblastic leukemia (r/r B-ALL) are non-response and relapse; it is urgent to reveal these mechanisms. Neutrophils play a critical role in the immunosuppressive tumor microenvironment (TME), which can hinder CAR T efficacy. Our previous research identified a subset of immunosuppressive neutrophils with a special phenotype (CD14-CD10-CD45-HLA-DR-SSC++, termed CD10- neuts), which suppress T cell function. Therefore, we speculate that CD10- neuts may also influence CAR T efficacy, and this study aims to clinically validate this hypothesis.

METHODS

We enrolled 44 patients with r/r B-ALL undergoing CD19 CAR T therapy and 47 healthy controls (HCs). Peripheral blood samples were obtained prior to CAR T infusion to detect CD10- neuts levels by flow cytometry. Key parameters included the percentage of CD10- neuts in neutrophils (CD10- neuts/neutrophils), in all nucleated cells (CD10- neuts/nucleated cells), and the absolute count of CD10- neuts. We analyzed the correlations between these indicators and therapeutic response, relapse-free survival (RFS), overall survival (OS), and CAR T cell persistence time.

RESULTS

CD10- neuts levels were significantly elevated in patients with r/r B-ALL compared to HCs. Additionally, non-responding patients exhibited higher CD10- neuts levels than those in remission. Specifically, CD10- neuts/neutrophils, CD10- neuts/nucleated cells, and absolute CD10- neuts count were 64.44% vs. 25.43% (p = 0.004), 28.61% vs. 9.81% (p = 0.018), and 766.1/μL vs. 152.9/μL (p = 0.04), respectively. Among these indices, only CD10- neuts/neutrophils emerged as an independent risk factor for CAR T response (OR = 19.8, p = 0.013), relapse (HR = 4.704, p = 0.004), and survival (HR = 6.417, p = 0.001). Patients with CD10- neuts/neutrophils ≥ 21.57% demonstrated significantly shorter RFS and OS compared to those with lower levels (p = 0.001; p = 0.0002). Furthermore, CD10- neuts/neutrophils were negatively correlated with the persistence time of CAR T cells.

CONCLUSIONS

As one of the key factors in the TME, abnormally elevated CD10- neuts correlate with CAR T therapy resistance. Targeting these neutrophils could enhance the effectiveness of CAR T treatment.

Finding a needle in a haystack: functional screening for novel targets in cancer immunology and immunotherapies

Genome-wide functional genetic screening has been widely used in the biomedicine field, which makes it possible to find a needle in a haystack at the genetic level. In cancer research, gene mutations are closely related to tumor development, metastasis, and recurrence, and the use of state-of-the-art powerful screening technologies, such as clustered regularly interspaced short palindromic repeat (CRISPR), to search for the most critical genes or coding products provides us with a new possibility to further refine the cancer mapping and provide new possibilities for the treatment of cancer patients. The use of CRISPR screening for the most critical genes or coding products has further refined the cancer atlas and provided new possibilities for the treatment of cancer patients. Immunotherapy, as a highly promising cancer treatment method, has been widely validated in the clinic, but it could only meet the needs of a small proportion of cancer patients. Finding new immunotherapy targets is the key to the future of tumor immunotherapy. Here, we revisit the application of functional screening in cancer immunology from different perspectives, from the selection of diverse in vitro and in vivo screening models to the screening of potential immune checkpoints and potentiating genes for CAR-T cells. The data will offer fresh therapeutic clues for cancer patients.

Leveraging the Immunomodulatory Potential of Ibrutinib for Improved Outcomes of T Cell-Mediated Therapies of B Cell Malignancies: A Narrative Review

Standard treatment options for B cell malignancies include immunochemotherapies and/or targeted therapies, which often provide temporary disease remission. However, many patients do not achieve complete remission with these treatments, develop resistance, and eventually experience disease relapse. New immunomodulatory treatments, such as T cell-based therapies, show promise in treating various types of blood cancers, including B cell malignancies. However, their effectiveness is often limited by the immunosuppressive tumor microenvironment and altered function of patient-derived T cells. Ibrutinib, a Bruton tyrosine kinase inhibitor, has been shown to restore immune balance and function in patients with chronic lymphocytic leukemia. Ibrutinib is being studied as adjuvant or combinatorial therapy with chimeric antigen receptor (CAR) T cells or T cell-engaging bispecific antibodies for the treatment of B cell malignancies. Current evidence suggests that ibrutinib could be beneficial when used before, during, or after CAR T cell administration, potentially providing higher complete response rates and reduced toxicity. In conclusion, existing evidence strongly supports the combined use of ibrutinib and T cell therapies. However, additional clinical trials are needed to further validate the effectiveness of this treatment strategy in patients with various B cell malignancies.

Loncastuximab in high-risk and heavily pretreated relapsed/refractory diffuse large B-cell lymphoma: a realworld analysis from 21 US centers

Outcomes in patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL) are poor. Loncastuximab- teserine (Lonca) is an antibody-drug conjugate which was approved by the Food and Drug Administration for the treatment of patients with R/R DLBCL who have received at least two prior lines of therapy, based on the results of the LOTIS-2 trial. However, there are limited data regarding its efficacy in the real-world setting. This retrospective study included 21 US centers and evaluated outcomes of patients with R/R DLBCL treated with Lonca. Our analysis comprises 187 patients with notably higher-risk baseline features compared to those of the LOTIS-2 population, including a higher proportion of patients with bulky disease (17% vs. 0%), high-grade B-cell histology (22% vs. 8%), and increased number of prior lines of therapy (median 4 vs. 3). The complete response rate was 14% and overall response rate was 32%. The median event-free survival and overall survival were 2.1 and 4.6 months, respectively. Those with bulky disease and high-grade B-cell histology had significantly worse outcomes, and those with non-germinal center cell of origin and a complete response to the most recent line of therapy demonstrated superior outcomes. In summary, in this largest retrospective cohort study of Lonca in the real-world setting, the response rates, event-free survival and overall survival were lower than those reported in LOTIS-2, which is likely reflective of its use in higher risk and more heavily pre-treated patients in the real world compared to the patients enrolled on a clinical study.

Adoptive cell therapy against tumor immune evasion: mechanisms, innovations, and future directions

Tumors employ a range of strategies to evade detection and eradication by the host's immune system. These include downregulating antigen expression, altering antigen presentation processes, and inhibiting immune checkpoint pathways. etc. Adoptive Cell Therapy (ACT) represents a strategy that boosts anti-tumor immunity. This is achieved by amplifying or genetically engineering immune cells, which are either sourced from the patient or a donor, in a laboratory setting. Subsequently, these cells are reintroduced into the patient to bolster their immune response against cancer. ACT has successfully restored anti-tumor immune responses by amplifying the activity of T cells from patients or donors. This review focuses on the mechanisms underlying tumor escape, including alterations in tumor cell antigens, the immunosuppressive tumor microenvironment (TME), and modulation of immune checkpoint pathways. It further explores how ACT can avddress these factors to enhance therapeutic efficacy. Additionally, the review discusses the application of gene-editing technologies (such as CRISPR) in ACT, highlighting their potential to strengthen the anti-tumor capabilities of T cells. Looking forward, the personalized design of ACT, combined with immune checkpoint inhibitors and targeted therapies, is expected to significantly improve treatment outcomes, positioning this approach as a key strategy in the field of cancer immunotherapy.

CAR-T cells in the treatment of multiple myeloma: an encouraging cell therapy

Multiple myeloma (MM) is a malignant disease of plasma cells that accounts for approximately 10% of all hematological malignancies and is characterized by a clonal proliferation of malignant plasma cells in the bone marrow. Numerous therapeutic strategies, including proteasome inhibitors, immunomodulators, monoclonal antibodies against CD38 and autologous stem cell transplantation, have prolonged the median survival of MM patients. Nevertheless, almost all MM patients suffer disease relapses due to drug resistance and eventually die from MM or MM-related complications. Chimeric antigen receptor (CAR) T-cell therapy is a novel immunotherapy strategy for MM and has shown encouraging results in several clinical trials. However, the use of CAR T-cell therapy for the treatment of MM is still associated with several difficulties, including antigen escape, poor persistence, an immunosuppressive microenvironment, cytokine release syndrome, immune effector cell-associated neurotoxicity syndrome, CAR T-cell-associated encephalopathy syndrome, cytopenia, and infections. In this review, we describe in detail the target antigens of CAR T cells in MM. We also comprehensively discuss recent innovations in the development of CAR T cells to improve clinical efficacy and strategies to overcome the limitations of CAR T-cell therapy in MM.

Inaticabtagene autoleucel in adult relapsed or refractory B-cell acute lymphoblastic leukemia

ABSTRACT

Before November 2023, CD19 chimeric antigen receptor (CAR) T-cell therapies had not been approved in China for patients with relapsed or refractory B-cell acute lymphoblastic leukemia (R/R B-ALL), leaving a significant unmet need. In response, inaticabtagene autoleucel (Inati-cel), a novel CD19 CAR T-cell therapy with a distinct single-chain variable fragment (HI19α), was developed and showed promising efficacy in preliminary clinical research. We conducted a phase 2, single-arm, multicenter study of Inati-cel in adult CD19+ R/R B-ALL in China. The primary end point was the overall remission rate (ORR) at the end of month 3. Forty-eight patients who underwent Inati-cel infusion were evaluated for both efficacy and safety. Among them, 34 patients achieved and maintained remission beyond 3 months, with a 3-month ORR of 70.8% (95% confidence interval [CI], 55.9-83.1). The best ORR was 85.4%, with all responders reaching minimal residual disease negativity. With a median follow-up of 23.7 months, the median duration of remission was 20.7 months (95% CI, 6.4 to not reached), and the median overall survival was not reached (95% CI, 13.0 months to not reached). Additionally, grade ≥3 cytokine release syndrome and neurologic events occurred in 12.5% and 6.2% of patients, respectively. The 2-year follow-up data suggest that Inati-cel demonstrates encouraging and durable responses with manageable safety profiles in R/R B-ALL. Based on the data from this pivotal trial, Inati-cel was approved as the first CAR T-cell therapy for adult R/R B-ALL in China and underscores its potential therapeutic benefits for this patient population. This trial was registered at www.ClinicalTrials.gov as #NCT04684147.

Comprehensive analysis of adverse events associated with T-cell engagers using the FAERS database

BACKGROUND

T-cell engagers (TCEs) are transformative immunotherapies with significant potential in treating hematologic malignancies and solid tumors. However, their real-world safety profiles remain inadequately characterized.

RESEARCH DESIGN AND METHODS

Using the FDA Adverse Event Reporting System (FAERS) database (October 2019 - September 2024, 8,747,158 reports), we analyzed adverse events (AEs) associated with nine TCEs. Disproportionality analysis identified overreported AEs, with 11,963 unique reports analyzed after deduplication.

RESULTS

Blinatumomab was the most reported TCE (n = 4,950), and Tarlatamab the least (n = 185). Predominant AEs included immune system disorders, particularly cytokine release syndrome (IC025 range: 6.08-7.47). Drug-specific signals included reproductive system and breast disorders (IC025: 2.74) and vascular disorders (IC025: 2.25) with Tebentafusp, renal and urinary disorders with Epcoritamab (IC025: 1.84), and eye disorders with Elranatamab (IC025: 1.81). Novel AEs were also uncovered, including second malignant neoplasms, vasogenic cerebral edema with Mosunetuzumab (IC025: 5.77, ROR025: 56.29), and hydronephrosis with Epcoritamab (IC025: 7.50, ROR025: 180.70). Early-onset events (0.5-9.5 days) were linked to four TCEs, while delayed-onset events (>20 days) were linked to five others.

CONCLUSIONS

This study highlights diverse AE profiles of TCEs, providing insights for clinicians to optimize their safe use in practice.

Mechanisms of antigen-dependent resistance to chimeric antigen receptor (CAR)-T cell therapies

Cancer immunotherapy has reshaped the landscape of cancer treatment over the past decades. Genetic manipulation of T cells to express synthetic receptors, known as chimeric antigen receptors (CAR), has led to the creation of tremendous commercial and therapeutic success for the treatment of certain hematologic malignancies. However, since the engagement of CAR-T cells with their respective antigens is solely what triggers their cytotoxic reactions against target cells, the slightest changes to the availability and/or structure of the target antigen often result in the incapacitation of CAR-T cells to enforce tumoricidal responses. This results in the resistance of tumor cells to a particular CAR-T cell therapy that requires meticulous heeding to sustain remissions in cancer patients. In this review, we highlight the antigen-dependent resistance mechanisms by which tumor cells dodge being recognized and targeted by CAR-T cells. Moreover, since substituting the target antigen is the most potent strategy for overcoming antigen-dependent disease relapse, we tend to highlight the current status of some target antigens that might be considered suitable alternatives to the currently available antigens in various cancers. We also propose target antigens whose targeting might reduce the off-tumor adverse events of CAR-T cells in certain malignancies.

Exploring the therapeutic efficacy difference in claudin18.2-targeted cell therapy revealed by single-cell sequencing

Chimeric antigen receptor T cell (CAR T) therapy has been successfully used to treat hematological malignancies. Nonetheless, its application to solid tumors remains challenging. Our previous analysis of the ongoing clinical trial (NCT03874897) demonstrated promising results in patients with advanced CLDN18.2-positive gastric cancer who received CT041 CAR T treatment. Here, we collected peripheral blood and ascites from five patients from the clinical trial 3 and 7 days (d) after CT041 infusion. Patients with a high proportion of naïve-like T cells were more likely to benefit from CT041 treatment. We found that high expression of CLDN18 in ascites epithelial cells correlated with a favorable prognosis, whereas ascites epithelial cells with high MYC expression and strong interactions between tumor cells and T cells were adverse prognostic factors for CT041 treatment. These findings may provide theoretical evidence for the screening of populations that can benefit from CAR T therapy and improve the efficacy of CAR T therapy.

UiO-66 MOFs-Based "Epi-Nano-Sonosensitizer" for Ultrasound-Driven Cascade Immunotherapy against B-Cell Lymphoma

B-cell lymphoma (BCL) is a hematological malignancy with high heterogeneity and represents an aggressive proliferation of mature B-cells. Despite the initial success of traditional treatments for BCL in clinical trials, a majority of patients eventually develop resistance to therapy and have poor clinical outcomes. Epigenetic dysregulation is a major contributor to the pathogenesis of BCL, and therapies targeting epigenetic pathways is a promising alternative strategy for treating BCL. Herein, we developed a metal-organic framework (MOF)-based nano-sonosensitizer for ultrasound-driven cascade immunotherapy against BCL. The nano-sonosensitizer was synthesized by encapsulating copper complex of the m6A-mRNA demethylase inhibitor into UiO-66-NH2, which possesses a Z-scheme heterostructure and allows efficient electron-hole pair separation for generating reactive oxygen species (ROS) under ultrasound activation. These CuR@UiO66 sonosensitizers were functionalized with mPEG-PO3 and anti-CD19 antibody, and the resulting CRUPPA19 particles could specifically accumulate in the BCL tissue and also target lymphoma cells that infiltrated into the bone marrow. Once internalized, CRUPPA19 could induce intracellular ROS production and apoptosis under ultrasound irradiation. Subsequently, ultrasonic stimulation triggered autophagy-mediated release of Cu and Rhein from CRUPPA19, thereby increasing protein lipoylation and global mRNA methylation, which led to cuproptosis and the transcriptional repression PDL1, respectively. These cascades synergistically induced immunogenic cell death in the tumors and promoted activation of CD8+ T cells, eventually leading to an antilymphoma immune response. CRUPPA19-mediated sono-immunotherapy not only eliminated the primary and metastatic lymphomas but also cleared lymphoma cells from the bone marrow. This study provided an insight into a MOF-based nanoepigenetic therapy platform with ultrasound-triggered cascade amplification for enhanced antihematological tumor immunity.

The CD64/CD28/CD3ζ chimeric receptor reprograms T-cell metabolism and promotes T-cell persistence and immune functions while triggering antibody-independent and antibody-dependent cytotoxicity

BACKGROUND

Recent studies have shown that CD32/CD8a/CD28/CD3ζ chimeric receptor cells directly kill breast cancer cells, suggesting the existence of cell surface myeloid FcγR alternative ligands (ALs). Here, we investigated the metabolism, ALs, cytotoxicity, and immunoregulatory functions of CD64/CD28/CD3ζ in colorectal cancer (CRC) and squamous cell carcinoma of the head and neck.

METHODS

The CD64/CD28/CD3ζ -SFG retroviral vector was used to produce viruses for T-cell transduction. T-cell expansion and differentiation were monitored via flow cytometry. Gene expression was assessed by RNA-seq. Bioenergetics were documented on a Seahorse extracellular flux analyzer. CD64/CD28/CD3ζ polarization was identified via confocal microscopy. Cytotoxicity was determined by MTT assay and bioluminescent imaging, and flow cytometry. Tridimensional antitumor activity of CD64/CD28/CD3ζ T cells was achieved by utilizing HCT116-GFP 3D spheroids via the IncuCyte S3 Live-Cell Analysis system. The intraperitoneal distribution and antitumor activity of NIR-CD64/CD28/CD3ζ and NIR-nontransduced T cells were investigated in CB17-SCID mice bearing subcutaneous FaDu Luc + cells by bioluminescent and fluorescent imaging. IFNγ was assessed by ELISA.

RESULTS

Compared to CD16/CD8a/CD28/CD3ζ T cells, CD32/CD8a/CD28/CD3ζ T cells, and non-transduced T cells, CD64/CD28/CD3ζ T cells exhibited the highest levels of cell expansion and persistence capacity. A total of 235 genes linked to cell division and 52 genes related to glycolysis were overexpressed. The glycolytic phenotype was confirmed by functional in vitro studies accompanied by preferential T-cell effector memory differentiation. Interestingly, oxamic acid was found to inhibit CD64-CR T cell proliferation, indicating the involvement of lactate. Upon CD64/CD28/CD3ζ T-cell conjugation with CRC cells, CD64/CD28/CD3ζ cells polarize at immunological synapses, leading to CRC cell death. CD64/CD28/CD3ζ T cells kill SCCHN cells, and in combination with the anti-B7-H3 mAb (376.96) or anti-EGFR mAb, these cells trigger antibody-dependent cellular cytotoxicity (ADCC) in vitro under 2D and 3D conditions. The 376.96 mAb combined with CD64/CD28/CD3ζ T cells had anti-SCCHN activity in vivo. In addition, they induce the upregulation of PD-L1 and HLA-DR expression in cancer cells via IFNγ. PD-L1 positive SCCHN cells in combination with anti-PD-L1 mAb and CD64-CR T cells were killed by ADCC, which enhanced direct cytotoxicity. These findings indicate that the glycolytic phenotype is involved in CD64-CR T cell proliferation/expansion. These cells mediate long-lasting HLA-independent cytotoxicity and ADCC in CRC and SCCHN cells.

CONCLUSIONS

CD64/CD28/CD3ζ T cells could significantly impact the rational design of personalized studies to treat CRC and SCCHN and the identification of novel FcγR ALs in cancer and healthy cells.

Tumor dormancy and relapse: understanding the molecular mechanisms of cancer recurrence

Cancer recurrence, driven by the phenomenon of tumor dormancy, presents a formidable challenge in oncology. Dormant cancer cells have the ability to evade detection and treatment, leading to relapse. This review emphasizes the urgent need to comprehend tumor dormancy and its implications for cancer recurrence. Despite notable advancements, significant gaps remain in our understanding of the mechanisms underlying dormancy and the lack of reliable biomarkers for predicting relapse. This review provides a comprehensive analysis of the cellular, angiogenic, and immunological aspects of dormancy. It highlights the current therapeutic strategies targeting dormant cells, particularly combination therapies and immunotherapies, which hold promise in preventing relapse. By elucidating these mechanisms and proposing innovative research methodologies, this review aims to deepen our understanding of tumor dormancy, ultimately facilitating the development of more effective strategies for preventing cancer recurrence and improving patient outcomes.

Selective JAK2 pathway inhibition enhances anti-leukemic functionality in CD19 CAR-T cells

The integration of molecular targeted therapeutics with chimeric antigen receptor T (CAR-T) cell therapy represents a novel strategy to amplify the anti-tumor efficacy of immunotherapy. While CD19-targeted CAR-T cells and Janus kinase (JAK) inhibitors have independently shown efficacy against certain B-cell leukemias, such as Philadelphia chromosome-like acute lymphoblastic leukemia, the concurrent use of JAK1/2 inhibitors, such as ruxolitinib, has been implicated in reducing CAR-T cell potency by inhibiting the JAK1-dependent T cell activation pathway. This study explores the combinatorial use of a selective type II JAK2 inhibitor, CHZ868, with CD19 CAR-T cells, revealing a synergistic enhancement of anti-leukemic activity across B-cell tumor models irrespective of JAK2 mutational status. CHZ868-mediated JAK2 inhibition did not induce the exhaustion of CAR-T cells, maintaining efficacy over repeated tumor challenges and significantly extending survival in mouse models engrafted with JAK2 inhibitor-resistant leukemia cells (median survival, CD19 CAR-T + CHZ868 vs. CD19 CAR-T + DMSO: 32 days vs. 26 days, p = 0.0303). Transcriptomic analyses suggest that CHZ868 impedes CAR-T cell differentiation while preserving their proliferative capacity, a crucial factor in maintaining CAR-T cell functionality. Therefore, the selective inhibition of the JAK2 pathway may potentiate CAR-T cell therapy and offer a viable treatment strategy for patients with resistant B-cell leukemias.

Upregulation of CD19 by low-dose chidamide promotes CAR T cells functionality in B-cell non-Hodgkin lymphoma

B-cell non-Hodgkin lymphoma (B-NHL) is a highly heterogeneous group of lymphopoietic malignancies that account for 85% to 90% of all non-Hodgkin lymphomas. In recent years, CD19 Chimeric antigen receptor T (CAR T) cell immunotherapy has significantly improved the cure rate of B-NHL patients, but there are still some patients who cannot achieve remission after treatment, or relapse after remission. Therefore, it is of great importance to overcome the drug resistance of CD19 CAR T cells after B-NHL treatment and reduce the recurrence rate of CD19 CAR T cells after B-NHL treatment. We found that low concentrations of chidamide did not enhance the ability of CD19 CAR T cells to kill B-NHL cells during and after preparation. B-NHL cells pretreated with chidamide were more likely to be killed by CD19 CAR T cells. CD19 CAR T cells secreted more cytokines (IL-2, TNF-α, and IFN-γ) after co-culture with B-NHL cells pretreated with chidamide. At the same time, the expression of CD19 on B-NHL cell surface was increased by chidamide. In vivo experiments showed that infusion of CD19 CAR T cells after chidamide bridging intervention can enhance the therapeutic effect of B-NHL and prolong the overall survival of mice. This study provides a new direction and theoretical foundation for CD19 CAR T cell therapy in B-NHL.

DNA lesion-gated dumbbell nanodevices enable on-demand activation of the cGAS-STING pathway for enhancing cancer immunotherapy

Utilizing the cGAS-STING pathway to combat immune evasion is one of the most promising strategies for enhancing cancer immunotherapy. However, current techniques for activating the cGAS-STING pathway often face a dilemma, mainly due to the balance between efficacy and safety. Here, we develop a uracil base lesion-gated dumbbell DNA nanodevice (UBLE) that allows on-demand activation and termination of the cGAS-STING pathway in tumor cells, thereby enhancing cancer immunotherapy. The UBLE integrates two deoxyuridines (dU) in the stem for DNA lesion recognition, two locked complementary primer sequences (primers A and B) for DNA self-assembly, and a Förster resonance energy transfer pair (Cy3 and Cy5) attached to the loop for activation assessment. Upon the orthogonal recognition of tumor-specific repair indicators (UDG and APE1), the UBLE undergoes a conformational change to create massive nicked double-stranded DNA (dsDNA) units. These units self-assemble to generate long fluorescent dsDNA structures, permitting selective evaluation and on-demand activation of the cGAS-STING pathway. Furthermore, we demonstrate that the UBLE can effectively activate the cGAS-STING pathway in tumor cells, enhancing NK cell-targeted cancer immunotherapy. This work develops a DNA lesion-gated strategy for on-demand activation and termination of the cGAS-STING pathway, affording an innovative avenue for enhancing cancer immunotherapy.

Cell therapy for scleroderma: progress in mesenchymal stem cells and CAR-T treatment

Cell therapy is an emerging strategy for precision treatment of scleroderma. This review systematically summarizes the research progress of mesenchymal stem cell (MSC) and chimeric antigen receptor T cell (CAR-T) therapies in scleroderma and discusses the challenges and future directions for development. MSCs possess multiple functions, including immunomodulation, anti-fibrosis, and promotion of vascular regeneration, all of which can improve multiple pathological processes associated with scleroderma. Studies have demonstrated that MSCs can alleviate skin fibrosis by inhibiting CCL2 production and reducing the recruitment of pathological macrophages; their paracrine effects can exert extensive regulatory functions. CAR-T cell therapy ca specifically target and eliminate autoreactive immune cells, exhibiting enhanced specificity and personalized potential. Different cell therapies may have complementary and synergistic effects in treating scleroderma, such as MSCs exerting their effects through paracrine mechanisms while CAR-T cells specifically eliminate pathological cells. Furthermore, cell-free therapies derived from MSCs, such as extracellular vesicles or exosomes, may help circumvent the limitations of MSC therapy. Although cell therapy has opened new avenues for the precision treatment of scleroderma, it still faces numerous challenges. In the future, it is essential to strengthen integration of basic and clinical research, establish standardized protocols for cell preparation and quality control, develop personalized treatment plans, and rationally combine cell therapy with existing treatment methods to maximize its advantages and improve patient prognosis and quality of life.

Photo-metallo-immunotherapy: Fabricating Chromium-Based Nanocomposites to Enhance CAR-T Cell Infiltration and Cytotoxicity against Solid Tumors

The infiltration and cytotoxicity of chimeric antigen receptor (CAR)-T cells are crucial for effective elimination of solid tumors. While metallo-immunotherapy is a promising strategy that can activate the antitumor immunity, its role in promoting CAR-T cell therapy remains elusive. The first single-element nanomaterial based on chromium nanoparticles (Cr NPs) for cancer photo-metallo-immunotherapy has been reported previously. Herein, an extended study using biodegradable polydopamine as a versatile carrier for these nanoparticles, enabling synergistic CAR-T cell therapy, is reported. The results show that these nanocomposites with or without further encapsulation of the anticancer drug alpelisib can promote the CAR-T cell migration and antitumor effect. Upon irradiation with near-infrared light, they caused mild hyperthermia that can "warm" the "cold" tumor microenvironment (TME). The administration of B7-H3 CAR-T cells to NOD severe combined immunodeficiency gamma mice bearing a human hepatoma or PIK3CA-mutated breast tumor can significantly inhibit the tumor growth after the induction of tumor hyperthermia by the nanocomposites and promote the secretion of serum cytokines, including IL-2, IFN-γ, and TNF-α. The trivalent Cr3+ ions, which are the major degradation product of these nanocomposites, can increase the CXCL13 and CCL3 chemokine expressions to generate tertiary lymphoid structures (TLSs) in the tumor tissues, facilitating the CAR-T cell infiltration.

Accelerating CAR-T Cell Therapies with Small-Molecule Inhibitors

Chimeric antigen receptor T-cell therapies have markedly improved the survival rates of patients with B-cell malignancies. However, their efficacy in other hematological cancers, such as acute myeloid leukemia, and in solid tumors has been limited. Key obstacles include the downregulation or loss of antigen expression on cancer cells, restricted accessibility to target cells, and the poor persistence of these "living drugs" because of the highly immunosuppressive tumor microenvironment. Additionally, manufacturing these immunotherapies presents significant challenges, and patients frequently experience side effects such as cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome. This review emphasizes the potential of small-molecule inhibitors, many of which are already approved for clinical use, to facilitate chimeric antigen receptor T-cell manufacturing, enhance their anti-tumor efficacy, and mitigate their side effects. Although substantial work remains, the robust pre-clinical data and the growing clinical interest suggest significant promise for using cancer signaling pathway inhibitors to enhance and refine chimeric antigen receptor T-cell therapy for both hematological and solid tumors. Exploring these combination strategies could lead to more effective therapies, offering new hope for patients with resistant forms of cancer.

The potential of antibody-drug conjugates for effective therapy in diffuse large B-cell lymphoma

INTRODUCTION

Antibody-drug conjugates (ADCs) are a rapidly evolving class of anti-cancer drugs with a significant impact on management of hematological malignancies including diffuse large B-cell lymphoma (DLBCL). ADCs combine a cytotoxic drug (a.k.a. payload) attached through a linker to a monoclonal antibody specific to a particular cancer antigen. Payloads include microtubule disruptors or DNA damaging chemicals. After attaching to the antigen, the ADCs are internalized, and the payload is dissociated from ADC by lysozymes and delivered to the intended site for exerting cytotoxic effects. This unique molecular design permits a better balance of efficacy and safety. Loncastuximab tesirine and polatuzumab vedotin are two ADCs approved in the U.S.A. for treatment of DLBCL.

AREAS COVERED

This review covers the efficacy and safety data of these two drugs. We will review new ADC-based combination regimens and novel constructs in development.

EXPERT OPINION

ADCs have made a significant impact in improving outcomes of DLBCL patients. Both polatuzumab vedotin and loncastuximab tesirine are established as useful therapeutics options, with polatuzumab vedotin currently approved in first line and relapsed/refractory setting, while loncastuximab tesirine is approved in relapsed setting. ADCs are effective with tolerable safety profile and currently many more ADCs are undergoing clinical trials.

Nanocarriers in glioblastoma treatment: a neuroimmunological perspective

Glioblastoma multiforme (GBM) is the most fatal brain tumor with a poor prognosis with current treatments, mainly because of intrinsic resistance processes. GBM is also referred to as grade 4 astrocytoma, that makes up about 15.4 % of brain cancers globally as well as 60-75 % of astrocytoma. The most prevalent therapeutic choices for GBM comprise surgery in combination with radiotherapy and chemotherapy, providing patients with an average survival of 6-14 months. Nanocarriers provide various benefits such as enhanced drug solubility, biocompatibility, targeted activity, as well as minimized side effects. In addition, GBM treatment comes with several challenges such as the presence of the blood-brain barrier (BBB), blood-brain tumor barrier (BBTB), overexpressed efflux pumps, infiltration, invasion, drug resistance, as well as immune escape due to tumor microenvironment (TME) and cancer stem cells (CSC). Recent research has focused on nanocarriers due to their ability to self-assemble, improve bioavailability, provide controlled release, and penetrate the BBB. These nano-based components could potentially enhance drug accumulation in brain tumor tissues and reduce systemic toxicity, making them a compelling solution for GBM therapy. This review captures the complexities associated with multi-functional nano drug delivery systems (NDDS) in crossing the blood-brain barrier (BBB) and targeting cancer cells. In addition, it presents a succinct overview of various types of targeted multi-functional nano drug delivery system (NDDS) which has exhibited promising value for improving drug delivery to the brain.

Advancements in immunotherapy for colorectal cancer treatment: a comprehensive review of strategies, challenges, and future prospective

PURPOSE

Colorectal cancer (CRC) remains one of the leading causes of cancer-related mortality worldwide. Metastatic colorectal cancer (mCRC) continues to present significant challenges, particularly in patients with proficient mismatch repair/microsatellite stable (pMMR/MSS) tumors. This narrative review aims to provide recent developments in immunotherapy for CRC treatment, focusing on its efficacy and challenges.

METHODS

This review discussed the various immunotherapeutic strategies for CRC treatment, including immune checkpoint inhibitors (ICIs) targeting PD-1 and PD-L1, combination therapies involving ICIs with other modalities, chimeric antigen receptor T-cell (CAR-T) cell therapy, and cancer vaccines. The role of the tumor microenvironment and immune evasion mechanisms was also explored to understand their impact on the effectiveness of these therapies.

RESULTS

This review provides a comprehensive update of recent advancements in immunotherapy for CRC, highlighting the potential of various immunotherapeutic approaches, including immune checkpoint inhibitors, combination therapies, CAR-T therapy, and vaccination strategies. The results of checkpoint inhibitors, particularly in patients with MSI-H/dMMR tumors, which have significant improvements in survival rates have been observed. Furthermore, this review also addresses the challenges faced in treating pMMR/MSS CRC, which remains resistant to immunotherapy.

CONCLUSION

Immunotherapy plays a significant role in the treatment of CRC, particularly in patients with MSI-H/dMMR tumors. However, many challenges remain, especially in treating pMMR/MSS CRC. This review discussed the need for further research into combination therapies, biomarker development, CAR-T cell therapy, and a deeper understanding of immune evasion mechanisms for CRC treatment.

Correlative studies reveal factors contributing to successful CAR-T cell therapies in cancer

Cellular and targeted immunotherapies have revolutionized cancer treatments in the last several decades. Successful cellular therapies require both effective and durable cytotoxic activity from the immune cells as well as an accessible and susceptible response from targeted cancer cells. Correlative studies from clinical trials as well as real-world data from FDA-approved therapies have revealed invaluable insights about immune cell factors and cancer cell factors that impact rates of response and relapse to cellular therapies. This review focuses on the flagship cellular therapy of engineered chimeric antigen receptor T-cells (CAR-T cells). Within the CAR-T cell compartment, we discuss discoveries about T-cell phenotype, transcriptome, epigenetics, cytokine signaling, and metabolism that inform the cell manufacturing process to produce the most effective and durable CAR-T cells. Within the cancer cell compartment, we discuss mechanisms of resistance and relapse caused by mutations, alternative splicing, post-transcriptional modifications, and cellular reprogramming. Continued correlative and mechanistic studies are required to help us further optimize cellular therapies in a variety of malignancies.

Leveraging CRISPR gene editing technology to optimize the efficacy, safety and accessibility of CAR T-cell therapy

Chimeric Antigen Receptor (CAR)-T-cell therapy has revolutionized cancer immune therapy. However, challenges remain including increasing efficacy, reducing adverse events and increasing accessibility. Use of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology can effectively perform various functions such as precise integration, multi-gene editing, and genome-wide functional regulation. Additionally, CRISPR screening using large-scale guide RNA (gRNA) genetic perturbation provides an unbiased approach to understanding mechanisms underlying anti-cancer efficacy of CAR T-cells. Several emerging CRISPR tools with high specificity, controllability and efficiency are useful to modify CAR T-cells and identify new targets. In this review we summarize potential uses of the CRISPR system to improve results of CAR T-cells therapy including optimizing efficacy and safety and, developing universal CAR T-cells. We discuss challenges facing CRISPR gene editing and propose solutions highlighting future research directions in CAR T-cell therapy.

Adoptive transfer of membrane-restricted IL-12-TCR T cells promotes antigen spreading and elimination of antigen-negative tumor variants

BACKGROUND

Adoptive T-cell therapy has demonstrated clinical activity in B-cell malignancies, offering hope for its application to a broad spectrum of cancers. However, a significant portion of patients with solid tumors experience primary or secondary resistance to this treatment modality. Target antigen loss resulting either from non-uniform antigen expression or defects in antigen processing and presentation machinery is one well-characterized resistance mechanism. Constitutively expressed membrane-anchored interleukin-12 (caIL-12) has demonstrated enhanced antitumor activity and low systemic exposure in multiple preclinical adoptive T-cell treatment models with homogeneous tumor antigen expression. In this study, we assess the therapeutic impact of caIL-12 on target antigen-negative variants in syngeneic mouse models.

METHODS

Target antigen-positive tumors were generated by transducing B16F10 melanoma cells (B16) or Lewis Lung Carcinoma cells (LLC) with a construct expressing the OVA antigen, SIINFEKL, tagged to ubiquitin (B16-U-OVA, LLC-U-OVA), while B16 or LLC tumors served as antigen-negative variants. C57BL/6J mice were subcutaneously injected with heterogeneous tumors composed of 80% B16-U-OVA and 20% B16. Bilateral tumors were established by injecting the left flank with B16-U-OVA or LLC-U-OVA tumors and the right flank injected with B16 or LLC tumors. The tumor-bearing mice then underwent 5.5 Gy total body irradiation, followed by adoptive transfer of OT-I TCR-T cells engineered with or without caIL-12.

RESULTS

TCR-T cells (OT-I) delivered caIL-12 to the B16-U-OVA tumor sites and induced robust tumor control and survival benefits in mice bearing a heterogeneous tumor with OVA-negative variants. caIL-12 exerted its effect on OVA-negative B16 variants primarily by priming and activating endogenous antitumor CD8 T cells via antigen spreading. In addition, antigen spreading induced by OT-I-caIL-12 resulted in controlling OVA-negative tumors implanted at distant sites. This therapeutic effect required antigen-specific TCR-T cells and caIL-12 to colocalize at the tumor site, along with endogenous CD8 T cells capable of recognizing shared tumor antigens.

CONCLUSION

Expression of caIL-12 by tumor-targeting T cells demonstrated therapeutic effect against target-antigen-negative tumor variants, primarily through the induction of antigen spreading. These findings highlight the potential of caIL-12 to address challenges of antigen escape and tumor heterogeneity that may limit the efficacy of T-cell therapy against solid tumors.

TET2 mutation in acute myeloid leukemia: biology, clinical significance, and therapeutic insights

TET2 is a critical gene that regulates DNA methylation, encoding a dioxygenase protein that plays a vital role in the regulation of genomic methylation and other epigenetic modifications, as well as in hematopoiesis. Mutations in TET2 are present in 7%-28% of adult acute myeloid leukemia (AML) patients. Despite this, the precise mechanisms by which TET2 mutations contribute to malignant transformation and how these insights can be leveraged to enhance treatment strategies for AML patients with TET2 mutations remain unclear. In this review, we provide an overview of the functions of TET2, the effects of its mutations, its role in clonal hematopoiesis, and the possible mechanisms of leukemogenesis. Additionally, we explore the mutational landscape across different AML subtypes and present recent promising preclinical research findings.

Unraveling the role of heavy metals xenobiotics in cancer: a critical review

Cancer is a multifaceted disease characterized by the gradual accumulation of genetic and epigenetic alterations within cells, leading to uncontrolled cell growth and invasive behavior. The intricate interplay between environmental factors, such as exposure to carcinogens, and the molecular cascades governing cell growth, differentiation, and survival contributes to cancer's development and progression. This review offers a comprehensive overview of key molecular targets and their roles in cancer development. Peroxisome proliferator-activated receptors are implicated in various cancers due to their role in regulating lipid metabolism, inflammation, and cell proliferation. Nuclear factor erythroid 2-related factor 2 protects cells from oxidative damage but can also promote tumor cell survival. Cytochrome P450 1B1 metabolizes exogenous and endogenous substances, and its increased expression is observed in several cancers. The constitutive androstane receptor regulates gene expression, and its dysregulation can lead to liver cancer. Transforming growth factor-beta 2 is involved in the development and progression of various cancers by dysregulating cell proliferation, differentiation, and migration. Chelation treatment has been investigated for removing heavy metals, while genetically altered immune cells show promise in treating specific cancers. Metal-organic frameworks and fibronectin targeting represent new directions in cancer treatment. While some heavy metals, such as arsenic, chromium, nickel, and cadmium, are known to have carcinogenic properties, others, like zinc, Copper, gold, bismuth, and silver, have many uses that highlight their potential as effective cancer control tactics. There are a variety of heavy metal-based technologies that show potential for improving cancer treatment methods, including targeted drug delivery, improved radiation, and diagnostic tools.

Claudin 1, 4, 6 and 18 isoform 2 as targets for the treatment of cancer (Review)

The 24 claudin (CLDN) genes in the human genome encode 26 representative CLDN family proteins. CLDNs are tetraspan‑transmembrane proteins at tight junctions. Because several CLDN isoforms, such as CLDN6 and CLDN18.2, are specifically upregulated in human cancer, CLDN‑targeting monoclonal antibodies (mAbs), antibody‑drug conjugates (ADCs), bispecific antibodies (bsAbs) and chimeric antigen receptor (CAR) T cells have been developed. In the present review, CLDN1‑, 4‑, 6‑ and 18.2‑targeting investigational drugs in clinical trials are discussed. CLDN18.2‑directed therapy for patients with gastric and other types of cancer is the most advanced area in this field. The mouse/human chimeric anti‑CLDN18.2 mAb zolbetuximab has a single‑agent objective response rate (ORR) of 9%, and increases progression‑free and overall survival in combination with chemotherapy. The human/humanized anti‑CLDN18.2 mAb osemitamab, and ADCs AZD0901, IBI343 and LM‑302, with single‑agent ORRs of 28‑60%, have been tested in phase III clinical trials. In addition, bsAbs, CAR T cells and their derivatives targeting CLDN4, 6 or 18.2 are in phase I and/or II clinical trials. AZD0901, IBI343, zolbetuximab and the anti‑CLDN1 mAb ALE.C04 have been granted fast track designation or priority review designation by the US Food and Drug Administration.

Cellular therapy in lymphoma

CD19-directed chimeric antigen receptor (CAR) T-cell therapy has had a dramatic impact on the natural history and survival of patients with high-risk B-cell non-Hodgkin lymphoma. Accompanying this success has been the development of new fields of medicine and investigation into toxicity risks and mitigation therapies, mechanisms of resistance and the development of novel and next generation products and strategies in order to address relapse, and issues related to global access and health care economics. This article is a survey of each of these areas as it pertains to the rapidly evolving field of CAR T-cell therapy, written by an International community of lymphoma experts, who also happen to be women.

Augmenting CAR T-cell Functions with LIGHT

Chimeric antigen receptor (CAR) T-cell therapy has resulted in remarkable clinical success in the treatment of B-cell malignancies. However, its clinical efficacy in solid tumors is limited, primarily by target antigen heterogeneity. To overcome antigen heterogeneity, we developed CAR T cells that overexpress LIGHT, a ligand of both lymphotoxin-β receptor on cancer cells and herpes virus entry mediator on immune cells. LIGHT-expressing CAR T cells displayed both antigen-directed cytotoxicity mediated by the CAR and antigen-independent killing mediated through the interaction of LIGHT with lymphotoxin-β receptor on cancer cells. Moreover, CAR T cells expressing LIGHT had immunostimulatory properties that improved the cells' proliferation and cytolytic profile. These data indicate that LIGHT-expressing CAR T cells may provide a way to eliminate antigen-negative tumor cells to prevent antigen-negative disease relapse.

Applications of cell therapy in the treatment of virus-associated cancers

A diverse range of viruses have well-established roles as the primary driver of oncogenesis in various haematological malignancies and solid tumours. Indeed, estimates suggest that approximately 1.5 million patients annually are diagnosed with virus-related cancers. The predominant human oncoviruses include Epstein-Barr virus (EBV), Kaposi sarcoma-associated herpesvirus (KSHV), hepatitis B and C viruses (HBV and HCV), human papillomavirus (HPV), human T-lymphotropic virus type 1 (HTLV1), and Merkel cell polyomavirus (MCPyV). In addition, although not inherently oncogenic, human immunodeficiency virus (HIV) is associated with immunosuppression that contributes to the development of AIDS-defining cancers (specifically, Kaposi sarcoma, aggressive B cell non-Hodgkin lymphoma and cervical cancer). Given that an adaptive T cell-mediated immune response is crucial for the control of viral infections, increasing research is being focused on evaluating virus-specific T cell therapies for the treatment of virus-associated cancers. In this Review, we briefly outline the roles of viruses in the pathogenesis of these malignancies before describing progress to date in the field of virus-specific T cell therapy and evaluating the potential utility of these therapies to treat or possibly even prevent virus-related malignancies.

Transcriptional rewiring in CD8+ T cells: implications for CAR-T cell therapy against solid tumours

T cells engineered to express chimeric-antigen receptors (CAR-T cells) can effectively control relapsed and refractory haematological malignancies in the clinic. However, the successes of CAR-T cell therapy have not been recapitulated in solid tumours due to a range of barriers such as immunosuppression, poor infiltration, and tumour heterogeneity. Numerous strategies are being developed to overcome these barriers, which include improving culture conditions and manufacturing protocols, implementing novel CAR designs, and novel approaches to engineering the T cell phenotype. In this review, we describe the various emerging strategies to improve CAR T cell therapy for solid tumours. We specifically focus on new strategies to modulate cell function and fate that have precipitated from the growing knowledge of transcriptional circuits driving T cell differentiation, with the ultimate goal of driving more productive anti-tumour T cell immunity. Evidence shows that enrichment of particular phenotypic subsets of T cells in the initial cell product correlates to improved therapeutic responses and clinical outcomes. Furthermore, T cell exhaustion and poor persistence are major factors limiting therapeutic efficacy. The latest preclinical work shows that targeting specific master regulators and transcription factors can overcome these key barriers, resulting in superior T cell therapeutic products. This can be achieved by targeting key transcriptional circuits promoting memory-like phenotypes or sustaining key effector functions within the hostile tumour microenvironment. Additional discussion points include emerging considerations for the field such as (i) targeting permutations of transcription factors, (ii) transient expression systems, (iii) tissue specificity, and (iv) expanding this strategy beyond CAR-T cell therapy and cancer.

Validation of a PD-1/CD28 chimeric switch receptor to augment CAR-T function in dogs with spontaneous B cell lymphoma

Chimeric antigen receptor (CAR) T cell therapy has achieved unprecedented clinical outcomes in patients with relapsed/refractory B cell leukemias; however, response rates in patients with large B cell lymphoma (LBCL) are less impressive. Expression of PD-1 on activated T cells and PD-L1 on malignant, stromal, and immune cells within the tumor microenvironment (TME) contribute to CAR-T exhaustion, hypofunction, and treatment failures. Here, a comparative approach is taken to develop a chimeric switch receptor (CSR) with potential to augment CAR-T persistence, function, and clinical efficacy in immune competent, pet dogs with spontaneous B cell lymphoma (BCL). We show that similar to human CAR-T cells, expression of a PD-1/CD28 CSR in canine CAR-T cells results in enhanced function against PD-L1+ targets and preserves central memory phenotype. We also demonstrate that these effects depend upon active CSR signaling. This work paves the way for in vivo studies in canine BCL patients to inform human trial design.

Regulation of CAR transgene expression to design semiautonomous CAR-T

Effective transgene expression is critical for genetically engineered cell therapy. Therefore, one of CAR-T cell therapy's critical areas of interest, both in registered products and next-generation approaches is the expression of transgenes. It turns out that various constitutive promoters used in clinical products may influence CAR-T cell antitumor effectiveness and impact the manufacturing process. Furthermore, next-generation CAR-T starts to install remotely controlled inducible promoters or even autonomous expression systems, opening new ways of priming, boosting, and increasing the safety of CAR-T. In this article, a wide range of constitutive and inducible promoters has been grouped and structured, making it possible to compare their pros and cons as well as clinical usage. Finally, logic gates based on Synthetic Notch have been elaborated, demonstrating the coupling of desired external signals with genetically engineered cellular responses.

IL-4 drives exhaustion of CD8+ CART cells

Durable response to chimeric antigen receptor T (CART) cell therapy remains limited in part due to CART cell exhaustion. Here, we investigate the regulation of CART cell exhaustion with three independent approaches including: a genome-wide CRISPR knockout screen using an in vitro model for exhaustion, RNA and ATAC sequencing on baseline and exhausted CART cells, and RNA and ATAC sequencing on pre-infusion CART cell products from responders and non-responders in the ZUMA-1 clinical trial. Each of these approaches identify interleukin (IL)-4 as a regulator of CART cell dysfunction. Further, IL-4-treated CD8+ CART cells develop signs of exhaustion independently of the presence of CD4+ CART cells. Conversely, IL-4 pathway editing or the combination of CART cells with an IL-4 monoclonal antibody improves antitumor efficacy and reduces signs of CART cell exhaustion in mantle cell lymphoma xenograft mouse models. Therefore, we identify both a role for IL-4 in inducing CART exhaustion and translatable approaches to improve CART cell therapy.