Cancer Immunotherapy Research Articles

Linear porokeratosis and the rationale of combining calcipotriol with 5-fluorouracil

Linear porokeratosis is one of the rare forms of porokeratosis and is also pre-malignant in nature. The term porokeratosis is a misnomer, as it is not a disorder of the sweat gland ducts, but rather a disorder of keratinization. There is no standard of therapy for porokeratosis and many topical therapies exist such as topical retinoids; keratolytics such as salicylic acid and urea; topical vitamin D3 analogs such as calcipotriol and calcipotriene, along with the newer 2% lovastatin creams with or without 2% cholesterol cream. We report this case of linear porokeratosis since we have combined 5% 5-fluorouracil cream and 0.005% calcipotriol ointment for both clinical cure and cancer immunotherapy. Although it is a common combination used in the treatment of actinic keratosis, another premalignant dermatosis, it has been uncommonly used in porokeratosis of Mibelli and never reported to be used in linear porokeratosis.

Immunogenic dying cells elicit potent anti-tumor T cell immunity against lung metastasis and tumorigenesis

PurposeImmune checkpoint blockades (ICBs) are promising, however they do not fit all types of tumor, such as those lack of tumor antigens. Induction of potent anti-tumor T cell immunity is critical for cancer therapy. In this study, we investigated the efficacy of immunotherapy via the immunogenic cell death (ICD) dying tumor cells in mouse models of lung metastasis and tumorigenesis.MethodsICD was induced by short exposure to lethal dose of chemotherapeutic drug doxorubicin (Dox), which initiated an irreversible ICD program in tumor cells. We immunized mice with ICD dying tumor cells in prevention, therapy in lung metastasis models, and Gprc5a-knockout (ko) model of lung tumorigenesis. T cells and macrophages isolated from lymph nodes or tumor tissues were analyzed by flow cytometry. Cytokines were analyzed by ELISA or Q-PCR analysis.ResultsImmunization with these live but ICD dying tumor cells induced potent tumor-specific anti-tumor T cell immunity, which not only protected host from challenge by these tumor cells in prevention and therapy in mouse model of lung metastasis, but also prevented tumors development in Gprc5a-ko mouse model of lung tumorigenesis. The lymphocytes from lymph nodes and tumor tissues exhibited greatly enhanced activities of Th1 cells and M1 macrophages.ConclusionImmunization with the ICD dying tumor cells evokes potent tumor-specific T cell immunity, which provides a novel approach for cancer immunotherapy.

Transforming Bacterial Pathogens into Wonder Tools in Cancer Immunotherapy.

Cancer immunotherapy has revolutionized cancer treatment due to its precise, target-specific approach compared to conventional therapies. However, treating solid tumors remains challenging as these tumors are inherently immunosuppressive, and their tumor microenvironment (TME) often limits therapeutic efficacy. Interestingly, certain bacterial species offer a promising alternative by exhibiting an innate ability to target and proliferate within tumor environments. Bacterial structural and functional components can activate innate and adaptive immune responses, creating tumor-suppressive conditions that reduce tumor mass. Additionally, bacteria can deliver effector molecules directly into tumor cells, inducing apoptotic and necrotic cell death. Despite their potential, the use of bacteria in cancer immunotherapy poses risks due to possible toxicities and unpredictable in vivo behavior. Advances in genetic engineering have addressed these concerns by enabling the development of attenuated bacterial strains with enhanced anticancer properties for safer medical applications. This review highlights the role of bacteria in TME modulation, recent strategies to bioengineer bacterial pathogens as therapeutic tools, and the synergistic effects of combining bacteria with other immunotherapies. It also discusses the challenges and prospects of translating this innovative approach into clinical practice, offering a comprehensive overview of bacteria-based cancer immunotherapy's potential to reshape the future of cancer treatment.

Generating allogeneic CAR-NKT cells for off-the-shelf cancer immunotherapy with genetically engineered HSP cells and feeder-free differentiation culture.

The clinical potential of current chimeric antigen receptor-engineered T (CAR-T) cell therapy is hampered by its autologous nature that poses considerable challenges in manufacturing, costs and patient selection. This spurs demand for off-the-shelf therapies. Here we introduce an ex vivo feeder-free culture method to differentiate gene-engineered hematopoietic stem and progenitor (HSP) cells into allogeneic invariant natural killer T (AlloNKT) cells and their CAR-armed derivatives (AlloCAR-NKT cells). We include detailed information on lentivirus generation and titration, as well as the five stages of ex vivo culture required to generate AlloCAR-NKT cells, including HSP cell engineering, HSP cell expansion, NKT cell differentiation, NKT cell deep differentiation and NKT cell expansion. In addition, we describe procedures for evaluating the pharmacology, antitumor efficacy and mechanism of action of AlloCAR-NKT cells. It takes ~2 weeks to generate and titrate lentiviruses and ~6 weeks to generate mature AlloCAR-NKT cells. Competence with human stem cell and T cell culture, gene engineering and flow cytometry is required for optimal results.

Nanomaterials in cancer immunotherapy: targeting cancer-associated fibroblasts

Emphasizing the significance of cancer-associated fibroblasts (CAFs), non-malignant yet pivotal players within the tumor microenvironment (TME), this review illuminates the role of inflammatory subtype (iCAF) as catalysts in cancer proliferation, metastasis, and therapeutic resistance. Given their paramount importance, targeting CAFs emerges as a robust strategy in the evolving landscape of cancer immunotherapy. Nanomaterials, distinguished by their unique features and malleability, hold considerable promise in biomedicine, especially in the precision-oriented domain of cancer therapy. Their aptitude for modulating immune responses, amplifying drug efficacy through precise delivery, and discerningly focusing on cells within the TME situates nanomaterials as formidable tools to transcend the boundaries set by conventional treatments. This review scrutinizes the convoluted interplay among CAFs, immune cells, and tumor cells within the TME. It further showcases widely utilized nanomaterials in cancer management. We underscore the potential of nanoscale drug delivery systems directed at CAFs, underscoring their transformative power in revolutionizing cancer therapies, enhancing precision, and culminating in improved patient outcomes.

A retrospective multicenter study on the efficacy and safety of disitamab vedotin monotherapy versus combination with anti-PD-1 immunotherapy in advanced gastric cancer

Novel therapeutic agents including disitamab vedotin (RC48, an antibody-drug conjugate) and immune-checkpoint inhibitors (e.g., PD-1 inhibitors) have provided new hope as an advanced gastric-cancer (GC) treatment. This multicenter retrospective study studied RC48 monotherapy (MT)’s efficacy and safety against its combination with anti-PD-1 immunotherapy (IT) in advanced GC. Patients treated with RC48 MT or RC48 combined with anti-PD-1 IT from July 2021 to April 2023 were recruited for the study. The progression-free survival (PFS), overall survival (OS), objective-response rate (ORR), disease-control rate (DCR), and safety were studied. After propensity score matching (PSM) (1:1), this study included 34 in the RC48 plus anti-PD-1 IT group and 34 in the RC48 MT group. The median PFS was significantly longer in the combination-therapy (CT) group than in the MT group (5.3 versus 3.8 months, HR: 0.51, 95% CI: 0.31–0.85, p = 0.010), and the median OS was also notably increased (10.0 versus 6.8 months, HR: 0.45, 95% CI: 0.27–0.77, p = 0.003). The ORR and DCR were higher in the combination group (41.18% versus 14.71%, p = 0.031; 61.76% versus 35.30%, p = 0.052). Moreover, subgroup analyses further revealed that those in the CT group experienced a longer PFS and OS, particularly those with high HER2 expression or a PD-L1 CPS score of 1 or higher. The combination therapy (CT) achieved acceptable tolerability and manageable adverse events. Furthermore, the most common grade 3–5 treatment-related adverse events (TRAEs) included decreased white-blood-cell (WBC) count, decreased neutrophil count, and anemia. No new safety risks were observed. In sum, the RC48 and anti-PD-1 IT combination showed good efficacy and a manageable safety profile, indicating its strong potential as an advanced GC therapeutic option.

Highly Efficient and Universal Degradation of PD‐L1 via Mitochondrial Oxidative Stress Evoked by Cationic AIE‐Active Photosensitizers for Cancer Immunotherapy

AbstractThe blockade of interactions between programmed death‐ligand 1 (PD‐L1) on cancer cell surfaces and programmed cell death‐1 (PD‐1) receptors on T cells is a crucial strategy in cancer immunotherapy. However, the continuous replenishment of PD‐L1 from intracellular stores presents a significant challenge that undermines therapeutic efficacy. Therefore, effective downregulation of intracellular PD‐L1 is essential for improving treatment outcomes. In this study, a novel approach that utilizes mitochondrial oxidative stress to achieve highly efficient and universal PD‐L1 degradation is presented. A cationic aggregation‐induced emission‐active photosensitizer, DPA‐B‐YP+, which generates reactive oxygen species (ROS) upon light activation to induce mitochondrial oxidative stress on demand is developed. Compared to traditional high‐performance PD‐L1 degraders such as metformin and berberine, ROS‐induced mitochondrial stress by DPA‐B‐YP+ demonstrates superior efficiency and broader applicability in PD‐L1 degradation across various tumor types. Mechanistic studies reveal that PD‐L1 degradation by DPA‐B‐YP+ occurs via the AMPK‐ubiquitination pathway. Furthermore, in a murine immunogenic “cold” tumor model, DPA‐B‐YP+ effectively degrades PD‐L1 and significantly enhances CD8+ T cell‐mediated immune responses upon light activation, without the need for additional drugs or immune adjuvants. These findings present a novel approach and material for PD‐L1 degradation, contributing to advancements in cancer immunotherapy.

PRDM1 is a key regulator of the natural killer T-cell central memory program and effector function.

Natural killer T cells (NKTs) are a promising platform for cancer immunotherapy, but few genes involved in regulation of NKT therapeutic activity have been identified. To find regulators of NKT functional fitness, we developed a CRISPR/Cas9-based mutagenesis screen that employs a guide RNA (gRNA) library targeting 1,118 immune-related genes. Unmodified NKTs and NKTs expressing a GD2-specific chimeric antigen receptor (GD2.CAR) were transduced with the gRNA library and exposed to CD1d+ leukemia or CD1d-GD2+ neuroblastoma cells, respectively, over six challenge cycles in vitro. Quantification of gRNA abundance revealed enrichment of PRDM1-specific gRNAs in both NKTs and GD2.CAR NKTs, a result that was validated through targeted PRDM1 knockout. Transcriptional, phenotypic, and functional analyses demonstrated that CAR NKTs with PRDM1 knockout underwent central memory-like differentiation and resisted exhaustion. However, these cells downregulated the cytotoxic mediator granzyme B and showed reduced in vitro cytotoxicity and only moderate in vivo antitumor activity in a xenogeneic neuroblastoma model. In contrast, shRNA-mediated PRDM1 knockdown preserved effector function while promoting central memory differentiation, resulting in GD2.CAR NKTs with potent in vivo antitumor activity. Thus, we have identified PRDM1 as a regulator of NKT memory differentiation and effector function that can be exploited to improve the efficacy of NKT-based cancer immunotherapies.

Endoscopic and imaging evaluations of the primary tumor response in patients with proficient mismatch repair colorectal cancer treated with neoadjuvant combination immunotherapy.

Neoadjuvant combination immunotherapy is a potential treatment option for patients with proficient mismatch repair/microsatellite stable colorectal cancer. Preoperative screening via endoscopy and imaging examinations could help identify patients who may potentially achieve a complete response after neoadjuvant combination immunotherapy. This study aims to evaluate the diagnostic accuracy of endoscopic and imaging examinations in predicting pathological complete response after neoadjuvant combination immunotherapy. This single-center, retrospective, observational study included patients diagnosed with colorectal cancer by biopsy between 2015 and 2023 at a tertiary referral center. The main outcome measures included endoscopic examination, imaging findings, and pathological results after neoadjuvant combination immunotherapy. This study included 36 patients with locally advanced proficient mismatch repair colorectal cancer. Postoperative pathology revealed that 17 patients (47.2%) achieved a complete response (ypT0N0). The sensitivity, specificity, and accuracy of the endoscopic ypT0N0 diagnosis were 62.5%, 80.0%, and 80.6%, respectively; those of imaging-based ypT0N0 diagnosis were 43.8%, 100%, and 75.0%, respectively; and those of the combined diagnosis were 37.5%, 100%, and 72.2%, respectively. The areas under the receiver-operating characteristic curve for the endoscopic and imaging ypT0N0 diagnoses were 0.768 and 0.706, respectively. The specificities of endoscopy and imaging for diagnosing complete response after neoadjuvant combination immunotherapy for colorectal cancer were high; however, sensitivities were low. Therefore, radical surgery should still be recommended for patients with an incomplete response based on either examination. Larger scale studies are required to determine if a watch-and-wait strategy is suitable for patients with a complete response based on these two examinations.

Personalized Nanovaccine Based on STING-Activating Nanocarrier for Robust Cancer Immunotherapy.

Tumor-specific T cells play a vital role in potent antitumor immunity. However, their efficacy is severely affected by the spatiotemporal orchestration of antigen-presentation as well as the innate immune response in dendritic cells (DCs). Herein, we develop a minimalist nanovaccine that exploits a dual immunofunctional polymeric nanoplatform (DIPNP) to encapsulate ovalbumin (OVA) via electrostatic interaction when the nanocarrier serves as both STING agonist and immune adjuvant in DCs. In vitro results reveal that the nanocarrier induces STING activation via facilitating interferon regulatory factor 3 phosphorylation by block poly 18-crown-6-yl methacrylate (P18C6MA) mediated K+ perturbation cascade with endoplasmic reticulum stress, and stimulates DC maturation via the Toll-like receptor 4 activation by primary amine. In vivo studies indicate that the smart nanovaccine dramatically inhibits tumor growth with a long-term immune memory response in both the B16-OVA and EG7-OVA tumor models. After combination with programmed death ligand-1 antibody (aPD-L1), mice survival rate is notably prolonged. In addition, DIPNP forms a personalized nanovaccine after resected autologous primary tumor cell membranes decoration with a high antitumor activity in a homologous distant tumor model. The rational design provides inspiration for personalized nanovaccine construction via immunofunctional nanocarriers.

Multiplexed inhibition of immunosuppressive genes with Cas13d for combinatorial cancer immunotherapy.

The complex nature of the immunosuppressive tumor microenvironment (TME) requires multi-agent combinations for optimal immunotherapy. Here we describe multiplex universal combinatorial immunotherapy via gene silencing (MUCIG), which uses CRISPR-Cas13d to silence multiple endogenous immunosuppressive genes in the TME, promoting TME remodeling and enhancing antitumor immunity. MUCIG vectors targeting four genes delivered by adeno-associated virus (AAV) (Cd274/Pdl1, Lgals9/Galectin9, Lgals3/Galectin3 and Cd47; AAV-Cas13d-PGGC) demonstrate significant antitumor efficacy across multiple syngeneic tumor models, remodeling the TME by increasing CD8+ T-cell infiltration while reducing neutrophils. Whole transcriptome profiling validates the on-target knockdown of the four target genes and shows limited potential off-target or downstream gene alterations. AAV-Cas13d-PGGC outperforms corresponding shRNA treatments and individual gene knockdown. We further optimize MUCIG by employing high-fidelity Cas13d (hfCas13d), which similarly showed potent gene silencing and in vivo antitumor efficacy, without weight loss or liver toxicity. MUCIG represents a universal method to silence multiple immune genes in vivo in a programmable manner, offering broad efficacy across multiple tumor types.

Yeast paves the way for cancer immunotherapy.

In this issue of Cell Chemical Biology, Rebeck etal.1 construct a system that enables Saccharomyces cerevisiae var. boulardii (Sb) to secrete immune checkpoint inhibitors, reducing intestinal tumor load. This safe and effective delivery platform using engineered yeast demonstrates potential for enhancing the efficacy of biologics.

Nano-Oncologic Vaccine for Boosting Cancer Immunotherapy: The Horizons in Cancer Treatment

Nano-Oncologic Vaccine for Boosting Cancer Immunotherapy: The Horizons in Cancer Treatment

Blocking PD-1 and Tim-3 Pathways to Overcome CD8+ T Cell Exhaustion and Enhance Cancer Immunotherapy Efficacy

Although significant progress has been made in cancer immunotherapy in recent years, its overall efficacy remains limited in a large number of patients. The interaction between the tumor microenvironment (TME) and CD8+ T cells is one of the core topics in cancer immunotherapy research. CD8+ T cells can play an anti-tumor role by recognizing and killing virus-infected or mutated cells. However, in the TME, as the tumor compresses immune cells, the function of them is impaired, and studies have found that relying on PD-1 alone is not enough to resist tumor cells. Therefore, by blocking the PD-1 and Tim-3 pathways to interfere with CD8+ T cell exhaustion (TEX), the performance of CD8+ T cells can be maximized, their survival period extended, and the efficacy of positive cancer immunotherapy improved. For patients with cancer who have failed to respond to immune checkpoint inhibitors as monotherapy, multi-targeted combination therapy may achieve better results.

Proximity Labeling and Genetic Screening Reveal that DSG2 is a Counter Receptor of Siglec-9 and Suppresses Macrophage Phagocytosis.

Cancer cells present sialylated glycoconjugates that modulate the activity of various immune cells within the tumor microenvironment through trans interaction with immunosuppressive Siglec receptors. Identifying counter receptors for Siglecs can provide valuable targets for cancer immunotherapy, but it presents significant challenges. Here, the identification of DSG2 (Desmoglein 2) as a dominant counter receptor of Siglec-9 in melanoma cells is reported, using a workflow that combines the strength of proximity labeling and the advantage of CRISPR knockout screening. It is further demonstrated that the interaction between DSG2 and Siglec-9 is mainly dependent on sialic acid-bearing N-glycans on DSG2. Importantly, blocking trans interaction between DSG2 and Siglec-9 significantly enhances macrophage phagocytosis of melanoma cells and, to a lesser extent, other cancer cells. The work thus suggests sialylated DSG2 as a potential "don't eat me" signal molecule with therapeutic potentials in cancer immunotherapy.

Potential and development of cellular vesicle vaccines in cancer immunotherapy.

Cancer vaccines are promising as an effective means of stimulating the immune system to clear tumors as well as to establish immune surveillance. In this paper, we discuss the main platforms and current status of cancer vaccines and propose a new cancer vaccine platform, the cytosolic vesicle vaccine. This vaccine has a unique structure that can integrate antigen and adjuvant carriers to improve the delivery efficiency and immune activation ability, which brings new ideas for cancer vaccine design. Tumor exosomes carry antigens and MHC-peptide complexes, which can provide tumor antigens to antigen-processing cells and increase the chances of recognition of tumor antigens by immune cells. DEVs play a role in amplifying the immune response by acting as carriers for the dissemination of antigenic substances in dendritic cells. OMVs, with their natural adjuvant properties, are one of the advantages for the preparation of antitumor vaccines. This paper presents the advantages of these three bacteria/extracellular vesicles as cancer vaccines and discusses the potential applications of functionally modified extracellular vesicles as cancer vaccines after cellular engineering or genetic engineering, as well as current clinical trials of extracellular vesicle vaccines. In summary, extracellular vesicle vaccines are a promising direction for cancer vaccine research.

Current landscape and future prospects of interleukin-2 receptor (IL-2R) agonists in cancer immunotherapy

ABSTRACT Immune checkpoint blockade (ICB) has significantly improved the survival for many patients with advanced malignancy. However, fewer than 50% of patients benefit from ICB, highlighting the need for more effective immunotherapy options. High-dose interleukin-2 (HD IL-2) immunotherapy, which is approved for patients with metastatic melanoma and renal cell carcinoma, stimulates CD8+ T cells and NK cells and can generate durable responses in a subset of patients. Moreover, HD IL-2 may have potential efficacy in patients whose disease has progressed following ICB and plays a vital role in expanding tumor-infiltrating lymphocyte (TIL) in TIL therapy. Despite its potential, the use of HD IL-2 is limited by severe toxicities such as hypotension and vascular leak syndrome. Additionally, only a few patients achieve a good outcome after HD IL-2 therapy. To address these challenges, numerous next-generation IL-2 receptor (IL-2 R) agonists have been developed to exhibit treatment effects while minimizing adverse events. This review will explore IL-2 biology, the clinical application of HD IL-2 therapy, and the development of novel IL-2 R agonists for cancer immunotherapy.

Orthogonalized human protease control of secreted signals.

Synthetic circuits that regulate protein secretion in human cells could support cell-based therapies by enabling control over local environments. Although protein-level circuits enable such potential clinical applications, featuring orthogonality and compactness, their non-human origin poses a potential immunogenic risk. In this study, we developed Humanized Drug Induced Regulation of Engineered CyTokines (hDIRECT) as a platform to control cytokine activity exclusively using human-derived proteins. We sourced a specific human protease and its FDA-approved inhibitor. We engineered cytokines (IL-2, IL-6 and IL-10) whose activities can be activated and abrogated by proteolytic cleavage. We used species specificity and re-localization strategies to orthogonalize the cytokines and protease from the human context that they would be deployed in. hDIRECT should enable local cytokine activation to support a variety of cell-based therapies, such as muscle regeneration and cancer immunotherapy. Our work offers a proof of concept for the emerging appreciation of humanization in synthetic biology for human health.

An OMV-Based Nanovaccine as Antigen Presentation Signal Enhancer for Cancer Immunotherapy.

Antigen-presenting cells (APCs) process tumor vaccines and present tumor antigens as the first signals to T cells to activate anti-tumor immunity, which process requires the assistance of co-stimulatory second signals on APCs. The immune checkpoint programmed death ligand 1 (PD-L1) not only mediates the immune escape of tumor cells but also acts as a co-inhibitory second signal on APCs. The serious dysfunction of second signals due to the high expression of PD-L1 on APCs in the tumor body results in the inefficiency of tumor vaccines. To overcome this challenge, a previously established Plug-and-Display tumor vaccine platform based on bacterial outer membrane vesicles (OMVs) is developed into an "Antigen Presentation Signal Enhancer" (APSE) by surface-modifying PD-L1 antibodies (αPD-L1). While delivering tumor antigens, APSE can activate the expression of co-stimulatory second signals in APCs due to the high immunogenicity of OMVs. More importantly, the surface-modified αPD-L1 binds to the co-inhibitory signals PD-L1, potentially restoring CD80 function and ensuring efficient co-stimulatory second signals and activation of anti-tumor immunity. The results reveal the importance of PD-L1 blockage in the initiation process of anti-tumor immunity, and the second signal modulation capability of APSE can expand the application potential of cancer vaccines to less immunogenic malignancies.

Advances in engineered bacteria vaccines for enhancing anti-cancer immunity

Advances in synthetic biology have enabled the development of tumor-targeted live bacterial therapeutics. In a recent study published in Nature , Redenti et al. engineered Escherichia coli Nissle 1917(EcNcΔlon/ΔompT/LLO+ nAg), which exploits the advantages of living medicines to deliver arrays of tumor-specific neoantigenic epitope in optimal environments, thereby providing a novel strategy for developing effective and durable cancer immunotherapies.