Anti-TIGIT therapies for solid tumors: a systematic review

Immune checkpoint inhibitor (ICI) therapy in central nervous system cancers: State-of-the-art and future outlook

Invasive central nervous system (CNS) cancers are an area where the development of breakthrough therapies is urgently needed. For instance, conditions such as glioblastoma multiforme (GBM) are associated with poor clinical prognosis, with the majority of trials offering no improvement to marginally enhanced survival. Unleashing the potential of targeting the immune system in CNS cancers has gained attention in recent years. Inhibition of immune checkpoints such as CTLA-4, PD-1/PD-L1, TIM-3, and LAG-3 has been attempted in recent trials. While potentially offering a notable edge over other immunotherapies, multi-organ adverse events have been found with the administration of immune checkpoint inhibitors (ICIs). The present review captures the state-of-the-art evidence on ICI treatments in different CNS cancers. Also, we discuss the value of combinational therapies involving ICIs as well as next-generation therapeutics such as bispecific antibodies targeting PD-1/LAG-3/TIM-3 and CRISPR-Cas9-edited PD-1-knock-out checkpoint-resistant CAR T-cells.

PRMT5 Inhibitor Synergizes with Chemotherapy to Induce Resembling Mismatch Repair Deficiency and Enhance Anti-TIGIT Therapy in Microsatellite-Stable Colorectal Cancer

Microsatellite stable (MSS) colorectal cancer (CRC) is considered an "immune-cold" tumor, accounting for ≈85% of all CRC cases. The overall response rate to chemotherapy combined with immune checkpoint inhibitors in MSS CRC is typically less than 10%. The specific mechanism that enhances chemotherapy sensitivity and mediated immunogenicity renders MSS CRC more responsive to immunotherapy remains elusive. Experiments in this study identify a DNA damage repair-related epigenetic gene, protein arginine methyltransferase 5 (PRMT5), whose inhibition enhances Irinotecan (CPT-11) sensitivity and synergistically induces a postmeiotic segregation increased 2 (PMS2)-deficient-like state, leading to the release of cytosolic double-stranded DNA. This activates the cyclic GMP-AMP synthase (cGAS)-stimulator of the IFN gene (STING) signaling pathway, thereby enhancing anti-tumor immunotherapy through dendritic cell-T cell-dependent functions. Importantly, combining the epigenetic anti-tumor drug GSK3326595 with CPT-11 significantly upregulates the immune receptor tyrosine-based inhibitory motif (TIGIT) level on CD8+ T cells and subsequently demonstrates impressive anti-tumor efficacy in vivo when additional anti-TIGIT is included. Collectively, this study reveals the crucial role of PRMT5 blockade combined with CPT-11 in inducing a mismatch repair deficiency-like state and provides a novel triple-drug combination therapy strategy as a potential treatment for patients with MSS CRC.

Precision enhancement of CAR-NK cells through non-viral engineering and highly multiplexed base editing

BACKGROUND

Natural killer (NK) cells' unique ability to kill transformed cells expressing stress ligands or lacking major histocompatibility complexes (MHC) has prompted their development for immunotherapy. However, NK cells have demonstrated only moderate responses against cancer in clinical trials.

METHODS

Advanced genome engineering may thus be used to unlock their full potential. Multiplex genome editing with CRISPR/Cas9 base editors (BEs) has been used to enhance T cell function and has already entered clinical trials but has not been reported in human NK cells. Here, we report the first application of BE in primary NK cells to achieve both loss-of-function and gain-of-function mutations.

RESULTS

We observed highly efficient single and multiplex base editing, resulting in significantly enhanced NK cell function in vitro and in vivo. Next, we combined multiplex BE with non-viral TcBuster transposon-based integration to generate interleukin-15 armored CD19 chimeric antigen receptor (CAR)-NK cells with significantly improved functionality in a highly suppressive model of Burkitt's lymphoma both in vitro and in vivo.

CONCLUSIONS

The use of concomitant non-viral transposon engineering with multiplex base editing thus represents a highly versatile and efficient platform to generate CAR-NK products for cell-based immunotherapy and affords the flexibility to tailor multiple gene edits to maximize the effectiveness of the therapy for the cancer type being treated.

Emerging clinical applications of single-cell RNA sequencing in oncology

Single-cell RNA sequencing (scRNA-seq) has revolutionized our understanding of complex tissues both in health and in disease. Over the past decade, scRNA-seq has been applied to tumour samples obtained from patients with cancer in hundreds of studies, thereby advancing the view that each tumour is a complex ecosystem and uncovering the diverse states of both cancer cells and the tumour microenvironment. Such studies have primarily investigated and provided insights into the basic biology of cancer, although considerable research interest exists in leveraging these findings towards clinical applications. In this Review, we summarize the available data from scRNA-seq studies investigating samples from patients with cancer with a particular focus on findings that are of potential clinical relevance. We highlight four main research objectives of scRNA-seq studies and describe some of the most relevant findings towards such goals. We also describe the limitations of scRNA-seq, as well as future approaches in this field that are anticipated to further advance clinical applicability.

New Therapeutic Targets TIGIT, LAG-3 and TIM-3 in the Treatment of Advanced, Non-Small-Cell Lung Cancer

The introduction of immunotherapy and target therapy into clinical practice has become a chance for many patients with cancer to prolong their survival while maintaining optimal quality of life. Treatment of lung cancer is excellent evidence of the progress of medical therapies. An understanding of the mechanisms of tumor development has led to the evolution of new methods of treatment. Immunoreceptors of T cells with the immunoglobulin domain ITIM, TIM-3 (T-cell immunoglobulin- and mucin domain-3-containing molecule 3), and LAG-3 (lymphocyte activation gene-3) represent new interesting therapeutic targets. The combination of anti-PD-1 and anti-CTLA-4 blockade has proven the possibility of strengthening the anti-tumor response by acting via two separate mechanisms. Adding additional checkpoints to the PD-1 blockade offers hope for further improvements in the effects of the treatment of patients and expanding the group responding to immunotherapy. This paper presents new promising molecular targets along with studies demonstrating the treatment results using them.

Targeting the poliovirus receptor to activate T cells and induce myeloid-derived suppressor cells to differentiate to pro-inflammatory macrophages via the IFN-γ-p-STAT1-IRF8 axis in cancer therapy

T cell immunoglobulin and ITIM domain (TIGIT) is one of the most important immune checkpoints expressed on lymphocytes, and poliovirus receptor (PVR, also CD155) serves as the most crucial ligand for TIGIT, harboring an important function in cancer cells and influencing the tumor microenvironment (TME). While it's well-established that TIGIT blockade could reverse immunosuppression, the question of whether direct inhibition of PVR yields comparable results remains to be fully elucidated. This study investigated the role of PVR within the TME on the LLC, CT26 and MC38 tumor models and found that direct blockade of PVR on tumor cells could trigger T cell activation, enhance the production of immunostimulatory cytokine IFN-γ, and drive the differentiation of intratumoral myeloid-derived suppressor cells (MDSCs) into pro-inflammatory macrophages through the IFN-γ-p-STAT1-IRF8 axis. Furthermore, this study found that the anti-PVR nanobody monotherapy reduced tumor volume in the CT26 and MC38 tumor models. Combination of anti-PVR nanobody and anti-PD-1 antibody was effective in the LLC, CT26 and MC38 tumor models and had acceptable toxicity. These findings collectively suggest that PVR exhibits considerable promise as a therapeutic target in the development of immunotherapies aimed at augmenting the anti-tumor immune response.

Neoadjuvant immune checkpoint therapy: Enabling insights into fundamental human immunology and clinical benefit

While immune checkpoint therapy (ICT) has revolutionized cancer treatment, most patients with advanced disease fail to achieve durable benefit. To address this challenge, it is essential to integrate mechanistic research with clinical studies to: (1) understand response mechanisms, (2) identify patient-specific resistance pathways, (3) develop biomarkers for patient selection, and (4) design novel therapies to overcome resistance. We propose that incorporating "direct-in-patient" studies into clinical trials is crucial for bridging the gap between fundamental science and clinical oncology. In this review, we first highlight recent clinical success of ICT in the neoadjuvant setting, where treatment is given in earlier disease stages to improve outcomes. We then explore how neoadjuvant clinical trials could be utilized to drive mechanistic laboratory-based investigations. Finally, we discuss novel scientific concepts that will potentially aid in overcoming resistance to ICT, which will require future clinical trials to understand their impact on human immune responses.

Promising New Anti-TIGIT Agents: Stealthy Allies in Cancer Immunotherapy

TIGIT (T cell immunoreceptor with immunoglobulin and tyrosine-based inhibitory motif (ITIM) domain), Vstm3, and VSIG9, are newly recognized immunological checkpoints. They are prominently expressed on CD4+ and CD8+ T cells, tumor-infiltrating lymphocytes (TILs), natural killer (NK) cells, and regulatory T cells (Tregs). The TIGIT (TIGIT) protein is crucial for immune modulation since it diminishes NK cell populations and hinders T cell activity in cancer patients and experimental models. CD155, the principal ligand of TIGIT in humans, has been recognized as a pivotal target for immunotherapy owing to its interaction with TIGIT. CD155 is linked to the efficacy of anti-programmed cell death protein 1 (PD-1) therapy, even without TIGIT expression, underscoring its importance in immune checkpoint suppression. Anti-TIGIT medicines, either independently or in conjunction with anti-PD-1 treatments, have demonstrated potential in augmenting immune responses to malignancies. This review examines the structural and functional characteristics of the TIGIT protein, new developments in anti-TIGIT drugs, and their prospective use in cancer immunotherapy.

Computational screening for natural compounds as potential immune checkpoint inhibitors against TIGIT, a new avenue in cancer immunotherapy

The TIGIT-PVR signalling pathway is a key mechanism of tumour immune evasion, making it an attractive target for cancer immunotherapy. Despite the recent advances in anti-TIGIT antibodies, monoclonal antibody-based therapeutics present significant challenges because of their immunogenicity and immune-related side effects. This study presents a new path involving natural compounds as potential small molecule inhibitors of TIGIT, providing a possible alternative to antibodies in cancer immunotherapy. Through a comprehensive in silico workflow combining structure-based virtual screening, ADMET analysis, Molecular docking and molecular dynamics simulations, six promising candidates, mostly of bacterial origin, were identified: Neomycin K, 4'-Deoxybutirosin A, 5-Glucosyl-neamine, S-11-A, 12-carbamoylstreptothricin E acid, and Zwittermicin A. These candidates demonstrated favourable binding energies, stable interactions, and the capacity to block TIGIT-PVR signalling. The compounds can potentially compete with PVR to bind to TIGIT, limiting the formation of the TIGIT-PVR complex, which typically activates an inhibitory cascade in T cells and NK cells, reducing their anti-tumour activity. By disrupting this interaction, the identified compounds have the potential to stimulate T cell and NK cell responses against cancer cells. Such natural compounds potentially provide better tissue penetration and reduced immunogenicity compared to conventional antibody therapies. The discovery of bacterial-derived compounds as TIGIT inhibitors presents a new direction in the investigation of microbial metabolites for cancer immunotherapy. This strategy not only identifies a new class of TIGIT inhibitors but also provides a robust computational framework for discovering and characterizing small molecule immune checkpoint inhibitors, paving the way for subsequent experimental validation to explore their efficacy in restoring anti-tumour immune responses and improving clinical outcomes for cancer patients.

Immune inhibitory receptor agonist therapeutics

The immune system maintains the health of an organism through complex sensing and communication mechanisms. Receptors on the surface of immune cells respond to stimuli resulting in activity described at its most basic as inhibitory or stimulatory. Significant progress in therapeutic intervention has occurred by modulating these pathways, yet much remains to be accomplished. Therapeutics that antagonize, or block, immune inhibitory receptor (IIR) pathways, such as checkpoint inhibitors in cancer are a key example. Antagonism of immune stimulatory receptors (ISRs) for dysregulated inflammation and autoimmunity have received significant attention. An alternative strategy is to agonize, or induce signaling, in immune pathways to treat disease. Agonism of ISRs has been employed with some success in disease settings, but agonist therapeutics of IIRs have great, untapped potential. This review discusses and highlights recent advances in pre-clinical and clinical therapeutics designed to agonize IIR pathways to treat diseases. In addition, an understanding of IIR agonists based on activity at a cellular level as either agonist suppression of stimulatory cells (SuSt), or a new concept, agonist suppression of suppressive cells (SuSu) is proposed.

C. S, Devkota HP, Khadka D. Immune Modulation and Immunotherapy in Solid Tumors: Mechanisms of Resistance and Potential Therapeutic Strategies

Understanding the modulation of specific immune cells within the tumor microenvironment (TME) offers new hope in cancer treatments, especially in cancer immunotherapies. In recent years, immune modulation and resistance to immunotherapy have become critical challenges in cancer treatments. However, novel strategies for immune modulation have emerged as promising approaches for oncology due to the vital roles of the immunomodulators in regulating tumor progression and metastasis and modulating immunological responses to standard of care in cancer treatments. With the progress in immuno-oncology, a growing number of novel immunomodulators and mechanisms are being uncovered, offering the potential for enhanced clinical immunotherapy in the near future. Thus, gaining a comprehensive understanding of the broader context is essential. Herein, we particularly summarize the paradoxical role of tumor-related immune cells, focusing on how targeted immune cells and their actions are modulated by immunotherapies to overcome immunotherapeutic resistance in tumor cells. We also highlight the molecular mechanisms employed by tumors to evade the long-term effects of immunotherapeutic agents, rendering them ineffective.

PD-1 transcriptomic landscape across cancers and implications for immune checkpoint blockade outcome

Programmed cell death protein 1 (PD-1) is a critical immune checkpoint receptor and a target for cancer immune checkpoint inhibitors (ICI). We investigated PD-1 transcript expression across cancer types and its correlations to clinical outcomes. Using a reference population, PD-1 expression was calculated as percentiles in 489 of 514 patients (31 cancer types) with advanced/metastatic disease. PD-1 RNA expression varied across and within cancer types; pancreatic and liver/bile duct malignancies displayed the highest rates of high PD-1 (21.82% and 21.05%, respectively). Elevated CTLA-4, LAG-3, and TIGIT RNA expression were independently correlated with high PD-1. Although high PD-1 was not associated with outcome in immunotherapy-naïve patients (n = 272), in patients who received ICIs (n = 217), high PD-1 transcript expression was independently correlated with prolonged survival (hazard ratio 0.40; 95%CI, 0.18-0.92). This study identifies PD-1 as an important biomarker in predicting ICI outcomes, and advocates for comprehensive immunogenomic profiling in cancer management.

Mitochondrial autophagy-related lncRNAs as prognostic biomarkers and therapeutic targets in gastric adenocarcinoma

Understanding the tumor microenvironment (TME) and the role of long noncoding RNAs (lncRNAs) in gastric adenocarcinoma (GA) is crucial, as these elements not only influence tumor progression but also provide opportunities for more precise prognostic assessments and tailored therapeutic interventions. This study identified mitochondrial autophagy-related lncRNAs, constructed a robust prognostic risk model, and explored the relationship between immune microenvironment characteristics and therapeutic responses. The model's performance was evaluated using ROC curves, Kaplan-Meier survival analysis, and nomograms. Our results demonstrate that the model outperforms traditional clinical factors, such as age and stage, in predicting patient outcomes. Immune cell analysis revealed distinct correlations with risk scores, and several immune checkpoint genes exhibited differential expression between risk groups. Drug sensitivity analysis suggested that low-risk patients could benefit more from ICIs, Oxaliplatin, Irinotecan, Afatinib, and Dabrafenib, while high-risk patients showed higher sensitivity to IGF1R3801, JQI, WZ4003 and NU7441. The identified lncRNA-based risk model provides a reliable prognostic tool for GA patients and highlights distinct immune microenvironment profiles that may influence treatment responses. These findings contribute to developing personalized therapeutic strategies targeting lncRNAs and the TME in GA.

Targeting novel regulated cell death: disulfidptosis in cancer immunotherapy with immune checkpoint inhibitors

The battle against cancer has evolved over centuries, from the early stages of surgical resection to contemporary treatments including chemotherapy, radiation, targeted therapies, and immunotherapies. Despite significant advances in cancer treatment over recent decades, these therapies remain limited by various challenges. Immune checkpoint inhibitors (ICIs), a cornerstone of tumor immunotherapy, have emerged as one of the most promising advancements in cancer treatment. Although ICIs, such as CTLA-4 and PD-1/PD-L1 inhibitors, have demonstrated clinical efficacy, their therapeutic impact remains suboptimal due to patient-specific variability and tumor immune resistance. Cell death is a fundamental process for maintaining tissue homeostasis and function. Recent research highlights that the combination of induced regulatory cell death (RCD) and ICIs can substantially enhance anti-tumor responses across multiple cancer types. In cells exhibiting high levels of recombinant solute carrier family 7 member 11 (SLC7A11) protein, glucose deprivation triggers a programmed cell death (PCD) pathway characterized by disulfide bond formation and REDOX (reduction-oxidation) reactions, termed "disulfidptosis." Studies suggest that disulfidptosis plays a critical role in the therapeutic efficacy of SLC7A11high cancers. Therefore, to investigate the potential synergy between disulfidptosis and ICIs, this study will explore the mechanisms of both processes in tumor progression, with the goal of enhancing the anti-tumor immune response of ICIs by targeting the intracellular disulfidptosis pathway.

Fc-competent TIGITx4-1BB bispecific antibody exerts potent long-lasting antitumor activity by potentiating CD8+ T cell activity and Fcγ receptor-mediated modulation of the tumor microenvironment

BACKGROUND

TIGIT was identified as a target immune checkpoint for overcoming resistance to PD-(L)1-blocking antibodies. However, the clinical efficacies of TIGIT antibodies were moderate in monotherapy and mixed in combination with PD-(L)1 antibodies. 4-1BB, a strong inducible costimulatory receptor, is another attractive target in antitumor therapeutics. This study investigated whether ABL112, an Fc-competent bispecific antibody targeting TIGIT and 4-1BB (TIGITx4-1BB), would enhance antitumor activity via Fcγ receptor (FcγR)-mediated macrophage activation and antibody-dependent cell-mediated functions.

METHODS

TIGIT-dependent 4-1BB activation and TIGIT-blocking activity were assessed using reporter Jurkat T cell lines expressing 4-1BB and TIGIT, respectively. In vivo antitumor activity was confirmed in h4-1BB knock-in mice. The main immune cell subsets associated with the antitumor activity of ABL112 were identified using antibodies for depleting specific immune cell subtypes or FcγR-blocking antibodies. The effects of a combined pembrolizumab or atezolizumab treatment with ABL112 were assessed in two mouse models with different genetic backgrounds. Statistical analysis was performed using one-way or two-way analysis of variance (ANOVA) with Dunnett's multiple-comparison test or one-way ANOVA with Fisher's multiple-comparison test.

RESULTS

ABL112 restored T cell activity by blocking TIGIT-CD155 interactions, based on a TIGIT blockade reporter assay. ABL112, an Fc-competent TIGITx4-1BB bispecific antibody, showed strong FcγRI-dependent 4-1BB activation along with TIGIT-dependent 4-1BB activation. In H22 tumor models expressing high levels of endogenous CD155, both ABL112 and parent TIGIT single-domain Ab showed potent tumor-suppressive activity; however, only ABL112 exerted long-lasting antitumor activity. ABL112 induced a marked decrease in Treg numbers, while augmenting the absolute number of CD8+ T cells and proportion of CD226+ CD8+ T cells. The expressions of CXCL10, CXCL11, IFN-γ, and TNF-α increased, indicating myeloid cell activation and potential modification of the tumor microenvironment to an inflammatory phenotype. ABL112 not only showed outstanding antitumor activity as a monotherapy, but also showed synergistic effects with PD-(L)1 mAb compared with the combined TIGIT-PD-(L)1 mAb treatments.

CONCLUSIONS

Through multiple mechanisms of action, ABL112 exerted potent tumor-killing activity and immune memory response alone or in combination with anti-PD-(L)1 therapies, representing a promising new cancer treatment strategy.

Triple-Negative Breast Cancer Systemic Treatment: Disruptive Early-Stage Developments for Overcoming Stagnation in the Advanced Pipeline

New breast cancer (BC) diagnoses will soon reach 2.5-3 million/year worldwide, with 15-25% of them being triple-negative breast cancer (TNBC), the most aggressive type, characterized for lacking the main pharmacological targets: estrogen and progesterone receptors (ERs and PRs), as well as HER2 overexpression. Therefore, chemotherapy remains the almost-unique systemic treatment for TNBC. However, some targeted therapies are recommended for use in combination with chemotherapy; namely, PARP inhibitors for BRCA-mutated TNBC, the immune checkpoint inhibitors pembrolizumab and atezolizumab, as well as the antibody-drug conjugates sacituzumab govitecan and trastuzumab deruxtecan, the latter for HER2low subtypes. Regardless of the limited benefits they provide, other treatments with similar mechanisms of action are being investigated in advanced clinical stages. Further, therapies that benefit other cancers, like PI3K/Akt/mTOR pathway and CDK4/6 inhibitors, are still being investigated for TNBC, although convincing results have not been obtained. Given this scenario, it might appear innovation for TNBC treatments has become stuck. However, the huge unmet medical need drives intense research into the biology of the disease. As a result, emerging disruptive therapies are being tested in early-stage trials, designed for novel targets and applying cutting-edge advances in immunotherapy and precision oncology.

TIGIT inhibitor M6223 as monotherapy or in combination with bintrafusp alfa in patients with advanced solid tumors: a first-in-human, phase 1, dose-escalation trial

BACKGROUND

M6223 is an intravenous (IV), Fc-competent, fully human, antagonistic, anti-T cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) antibody. Bintrafusp alfa (BA) is a bifunctional fusion protein that simultaneously blocks nonredundant immunosuppressive TGF-β and PD-(L)1 pathways.

METHODS

This first-in-human, dose-escalation study in patients with advanced solid tumors (N=58; aged ≥18 years, ECOG PS≤1) evaluated M6223 alone (Part 1A, n=40; M6223 10-2400 mg every 2 weeks, n=32; M6223 2400 mg every 3 weeks, n=8) or with BA (Part 1B, n=18; M6223 300-1600 mg with BA 1200 mg; both every 2 weeks, intravenous). Primary objectives were safety, tolerability, maximum tolerated dose (MTD) and recommended dose for expansion (RDE). Additional objectives included pharmacokinetics, pharmacodynamics and clinical activity (NCT04457778).

RESULTS

Two dose-limiting toxicities were observed: grade 3 adrenal insufficiency (Part 1A: M6223 900 mg every 2 weeks) and grade 3 anemia (Part 1B: M6223 300 mg, only BA related). MTD was not reached. Overall, median overall survival and progression-free survival were 7.6 (95% CI 4.9, 12.0) and 1.4 (95% CI 1.3, 1.8) months, respectively. Stable disease as best response was observed in 13 (32.5%) and 5 (27.8%) patients in parts 1A and 1B, respectively. M6223±BA displayed a linear pharmacokinetic profile. Anti-TIGIT mode-of-action-related pharmacodynamic effects were observed in peripheral blood and in tumor tissue. RDEs were 1600 mg every 2 weeks or 2400 mg every 3 weeks for M6223 monotherapy and 1600+1200 mg every 2 weeks for M6223+BA.

CONCLUSIONS

M6223±BA had a manageable safety profile, with RDEs defined for both monotherapy and combination therapy. Further evaluation of M6223 is ongoing in combination with the PD-L1 inhibitor avelumab in patients with advanced urothelial carcinoma (JAVELIN Bladder Medley; NCT05327530).

TRIAL REGISTRATION NUMBER

NCT04457778.

Immunomodulation of Pancreatic Cancer via Inhibition of SUMOylation and CD155/TIGIT Pathway

Pancreatic ductal adenocarcinoma (PDAC) is the deadliest major cancer and has a profoundly immunosuppressive tumor microenvironment (TME). Previous studies have shown that inhibition of the E1 enzyme, which catalyzes the small ubiquitin-like modifiers (SUMO), with the small molecule TAK-981, can reprogram the TME to enhance immune activation and suppress tumor growth. We found that the CD-155/TIGIT pathway, a key regulator of immune evasion in PDAC, is influenced by SUMOylation. We hypothesized that the combination of SUMO E1 and TIGIT inhibition would synergistically induce anti-tumor immune effects. We used a clinically relevant orthotopic mouse model that consistently develops liver metastases to study this combination therapy alone and in the perioperative setting with surgical resection. The combination of SUMO E1 and TIGIT inhibition significantly prolonged survival. Complete responders exhibited protective immunity and enhanced T cell reactivity to model-specific alloantigens. Complementary immune analyses of resected tumors demonstrated that combination therapy more significantly reduces the abundance of regulatory FOXP3+CD4+ T cells than each monotherapy alone. The findings suggest that SUMO E1 inhibition enhances antibody-mediated elimination of Tregs through innate immune cells, potentially by activation of type I interferon responses. Our results highlight a mechanism to enhance the efficacy of anti-TIGIT therapy.

Brief Summary

SUMOylation is a post-translational modification process critical for cancer. Inhibition of SUMOylation can improve the sensitivity of pancreatic cancer to immune checkpoint inhibition.

Warming-up the immune cell engagers (ICEs) era in breast cancer: state of the art and future directions

The advent of immune checkpoint inhibitors (ICIs) has deeply reshaped the therapeutic algorithm of triple-negative breast cancer (TNBC). However, there is considerable scope for better engagement of the immune system in other BC subtypes. ICIs have paved the way for investigations into emerging immunotherapeutic strategies, such as immune cell engagers (ICEs) that work by promoting efficient tumor cell killing through the redirection of immune system against cancer cells. Most ICEs are bispecific antibodies that simultaneously recognize and bind to both cancer and immune cells generating an artificial synapse. Major side effects are cytokine release syndrome, hepatotoxicity, and neurotoxicity related to inappropriate immune system activation. Here, we provide a comprehensive overview of this compounds, the available preclinical and clinical evidence supporting their investigation and development in BC also highlighting the challenges that have prevented their widespread use in oncology. Finally, major strategies are explored to broaden their use in BC.

Resistance mechanisms to immune checkpoint inhibitors: updated insights

The last decade has witnessed unprecedented succusses with the use of immune checkpoint inhibitors in treating cancer. Nevertheless, the proportion of patients who respond favorably to the treatment remained rather modest, partially due to treatment resistance. This has fueled a wave of research into potential mechanisms of resistance to immune checkpoint inhibitors which can be classified into primary resistance or acquired resistance after an initial response. In the current review, we summarize what is known so far about the mechanisms of resistance in terms of being tumor-intrinsic or tumor-extrinsic taking into account the multimodal crosstalk between the tumor, immune system compartment and other host-related factors.

Differential Role of NKG2A/HLA-E Interaction in the Outcomes of Bladder Cancer Patients Treated with M. bovis BCG or Other Therapies

Background: Immunotherapy is gaining great relevance in both non-muscle-invasive bladder cancer (NMIBC), with the use of bacille Calmette-Guerin (BCG), and in muscle-invasive BC (MIBC) with anti-checkpoint therapies blocking PD-1/PD-L1, CTLA-4/CD80-CD86, and, more recently, NKG2A/HLA-E interactions. Biomarkers are necessary to optimize the use of these therapies. Methods: We evaluated killer-cell immunoglobulin-like receptors (KIRs) and HLA-I genotyping and the expression of NK cell receptors in circulating T and NK lymphocytes at diagnosis in 325 consecutive BC patients (151 treated with BCG and 174 treated with other therapies), as well as in 648 patients with other cancers and 973 healthy donors as controls. The proliferation and production of cytokines and cytotoxicity were evaluated in peripheral blood mononuclear cells, stimulated in vitro with anti-CD3/CD28 or BCG, from selected patients based on HLA-B -21M/T dimorphism (NKG2A ligands). Results: The HLA-B -21M/T genotype showed opposing results in BC patients treated with BCG or other therapies. The MM genotype, compared to MT and TT, was associated with a longer 75th-percentile overall survival (not reached vs. 68.0 ± 13.7 and 52.0 ± 8.3 months, p = 0.034) in BCG, but a shorter (8.0 ± 2.4 vs. 21.0 ± 3.4 and 19.0 ± 4.9 months, p = 0.131) survival in other treatments. The HLA-B -21M/T genotype was an independent predictive parameter of the progression-free survival (HR = 2.08, p = 0.01) and the OS (HR = 2.059, p = 0.039) of BC patients treated with BCG, together with age and tumor histopathologic characteristics. The MM genotype was associated with higher counts of circulating CD56bright, fewer KIR2DL1/L2+ NK cells, and lower NKG2A expression, but not with differential in vitro NK cell functionality. Conclusions: The HLA-B -21M/T is independently associated with BC patient outcomes and can help to optimize the use of new immunotherapies in these patients.

Learning from Other Tumors: Pathways for Progress and Overcoming Challenges in Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a group of complex and heterogeneous tumors originating from the epithelial cells of bile ducts that can occur in intrahepatic, perihilar, or distal localizations [...].

Non-Genetic Biomarkers in Merkel Cell Carcinoma: Prognostic Implications and Predictive Utility for Response to Anti-PD-(L)1 Immune Checkpoint Inhibitors

Merkel cell carcinoma (MCC) is a skin cancer that arises due to either Merkel cell polyomavirus infection (MCPyV) or ultraviolet (UV) radiation exposure, presenting primarily in the head and neck region of fair-skinned males. The recent success of PD-(L)1 immune checkpoint inhibitors (ICIs) in locally advanced/metastatic MCC, with an objective response rate (ORR) around 50% and improved survival, as a first-line treatment has moved ICIs to the forefront of therapy for MCC and generated interest in identifying biomarkers to predict clinical response. The MCC tumour microenvironment (TME) contains various components of the adaptive and innate immune system. These components can contribute to tumour immune escape through immunosuppression by preventing entrance of other immune cells or by aiding in the cytotoxic clearance of tumour cells. We aim to combine information from studies of baseline and on-treatment monitoring of the TME to help predict the success of ICIs in MCC. This review enhances the understanding of how CD8 T cells, γδ T cells and macrophages may impact predictions of response rates to ICIs in MCC patients. These immune cells are non-genetic biomarkers that can also be used to determine prognosis in MCC treatment.

PVR exposure influences the activation, adhesion, and protein expression of human CD8+ T cells, including the CD96-mediated transfer of PVR

Poliovirus receptor (PVR) ligands have gained attention as immunotherapy targets, yet their regulation remains unclear. Here, we examine the impact of PVR exposure on primary human CD8+ T cells. We used flow cytometry and Western blot analysis to quantify expression of PVR and its ligands in naïve and effector T cells and used adhesion assays and enzyme-linked immunosorbent assay (ELISA) to assess the impact of PVR on T cell adhesion and cytokine production. Stimulation with phytohemagglutinin P strongly increased DNAM-1 expression and caused a less robust and more variable increase in TIGIT expression. Exposure to PVR-Fc enhanced the CD8+ T cell adhesion to ICAM-1-coated plates in a dose-dependent manner, while exposure to PVR-expressing K32 cells mildly decreased CD8+ T cell interferon γ release. However, PVR exposure strongly decreased the expression of DNAM-1, TIGIT, and CD96. The reduction of DNAM-1, TIGIT, and CD96 induced by PVR was dominant to the increase caused by T cell receptor signaling. The impact of PVR on their expression was completely abolished by the Q63R and F128R point mutations of PVR, while DNAM-1 was partially rescued by inhibitors of Src and protein kinase C. Additionally, PVR exposure along with T cell receptor signaling promoted the transfer of surface proteins including PVR from K32 cells to CD8+ T cells. This PVR transfer was mediated by the IgV domain of PVR and CD96 on CD8+ T cells and required cellular contact. Our findings collectively demonstrate that PVR engagement has a mild antagonistic effect on interferon γ production but strongly impacts CD8+ T cell adhesion and protein expression.

Enhancement of Human Immunodeficiency Virus-Specific CD8+ T Cell Responses with TIGIT Blockade Involves Trogocytosis

Natural killer (NK) and CD8+ T cell function is compromised in human immunodeficiency virus type 1 (HIV-1) infection by increased expression of inhibitory receptors such as TIGIT (T cell immunoreceptor with Ig and ITIM domains). Blocking inhibitory receptors or their ligands with monoclonal antibodies (mAb) has potential to improve antiviral immunity in general and facilitate HIV eradication strategies. We assessed the impact of TIGIT engagement and blockade on cytotoxicity, degranulation, and interferon-gamma (IFN-γ) production by CD8+ T cells from persons living with HIV (PLWH). The effect of TIGIT engagement on non-specific anti-CD3-redirected cytotoxicity was assessed in redirected cytotoxicity assays, and the effect of TIGIT blockade on HIV-specific CD8+ T cell responses was assessed by flow cytometry. In 14/19 cases where peripheral blood mononuclear cells (PBMC) mediated >10% redirected cytotoxicity, TIGIT engagement reduced the level of cytotoxicity to <90% of control values. We selected PLWH with >1000 HIV Gag or Nef-specific IFN-γ spot forming cells per million PBMC to quantify the effects of TIGIT blockade on HIV-specific CD8+ T cell responses by flow cytometry. Cell surface TIGIT expression decreased on CD8+ T cells from 23/40 PLWH following TIGIT blockade and this loss was associated with increased anti-TIGIT mAb fluorescence on monocytes. In total, 6 of these 23 PLWH had enhanced HIV-specific CD8+ T cell degranulation and IFN-γ production with TIGIT blockade, compared to 0/17 with no decrease in cell surface TIGIT expression. Reduced CD8+ T cell TIGIT expression with TIGIT blockade involved trogocytosis by circulating monocytes, suggesting that an effector monocyte population and intact fragment crystallizable (Fc) functions are required for mAb-based TIGIT blockade to effectively enhance HIV-specific CD8+ T cell responses.

Next-generation combination approaches for immune checkpoint therapy

Immune checkpoint therapy has revolutionized cancer treatment, leading to dramatic clinical outcomes for a subset of patients. However, many patients do not experience durable responses following immune checkpoint therapy owing to multiple resistance mechanisms, highlighting the need for effective combination strategies that target these resistance pathways and improve clinical responses. The development of combination strategies based on an understanding of the complex biology that regulates human antitumor immune responses has been a major challenge. In this Review, we describe the current landscape of combination therapies. We also discuss how the development of effective combination strategies will require the integration of small, tissue-rich clinical trials, to determine how therapy-driven perturbation of the human immune system affects downstream biological responses and eventual clinical outcomes, reverse translation of clinical observations to immunocompetent preclinical models, to interrogate specific biological pathways and their impact on antitumor immune responses, and novel computational methods and machine learning, to integrate multiple datasets across clinical and preclinical studies for the identification of the most relevant pathways that need to be targeted for successful combination strategies.

Neoadjuvant immunotherapy strategies for resectable non-small cell lung cancer (NSCLC): Current evidence among special populations and future perspectives

About one third of patients with Non-Small Cell Lung Cancer (NSCLC) presents at diagnosis with localized or locally advanced disease amenable to curative surgical resection. Surgical operability refers to stage I to IIIA and selected stage IIIB NSCLC. One of the main challenges in the management of early-stage resectable NSCLC is the optimization of available therapeutic strategies to prevent local and distant disease relapse, thus improving survival outcomes. There is evidence supporting the clinical use of both adjuvant and neoadjuvant immunotherapy-based strategies for resected/resectable, stage IB-IIIA NSCLC. Available data from randomized phase III trials have led to the incorporation of several immune checkpoint blockers (ICBs) into the international guidelines for early-stage NSCLC. Preclinical rationale of targeting specific subsets of T-cells by acting early on immune checkpoint receptors (e.g., PD-(L)1 and CTLA-4) is strong. Recent evidence is in favor of the neoadjuvant approach alone or as a part of perioperative strategy, demonstrating survival benefit. Combining neoadjuvant chemotherapy and immunotherapy before surgery results in both pathologic complete response (pCR) and major pathologic response (MPR) improvement, and survival outcomes, with no major safety issues. In this review, we summarize the rationale behind neoadjuvant/perioperative immunotherapy strategies and, due to the clinical relevance of immunotherapy in resectable NSCLC, we provide current evidence of this cutting-edge approach among special populations including older adults, women, and oncogene addicted NSCLC. To conclude, we present future perspectives in the use of immunotherapy for operable NSCLC with a special focus on novel investigational combinations underway.

Turning Cancer Immunotherapy to the Emerging Immune Checkpoint TIGIT: Will This Break Through the Limitations of the Legacy Approach?

The discovery of immune checkpoints (ICs) has pushed cancer treatment into the next era. As an emerging immune checkpoint, the TIGIT/CD155 axis inhibits the cytotoxicity of T and NK cells through multiple pathways. Immune checkpoint inhibitors (ICIs) targeting TIGIT are hopefully expected to address the issue of unresponsiveness to anti-PD-(L)1 monoclonal antibodies (mAbs) by combination therapy. This paper presents insights on the expression, structure and mechanism of action of TIGIT, as well as the principles and methods of designing mAbs targeting TIGIT and their clinical data. The advantages and disadvantages of targeting TIGIT using mAbs, bispecific and tri-specific antibodies (bsAbs and tsAbs), peptides, and compounds, in addition to potential combination therapies of anti-TIGIT with anti-PD-1 or cancer vaccines, are addressed. Finally, perspectives on current immunotherapies targeting TIGIT are discussed.

Exploring the Immunoresponse in Bladder Cancer Immunotherapy

Bladder cancer (BC) represents a wide spectrum of diseases, ranging from recurrent non-invasive tumors to advanced stages that require intensive treatments. BC accounts for an estimated 500,000 new cases and 200,000 deaths worldwide every year. Understanding the biology of BC has changed how this disease is diagnosed and treated. Bladder cancer is highly immunogenic, involving innate and adaptive components of the immune system. Although little is still known of how immune cells respond to BC, immunotherapy with bacillus Calmette-Guérin (BCG) remains the gold standard in high-risk non-muscle invasive BC. For muscle-invasive BC and metastatic stages, immune checkpoint inhibitors targeting CTLA-4, PD-1, and PD-L1 have emerged as potent therapies, enhancing immune surveillance and tumor cell elimination. This review aims to unravel the immune responses involving innate and adaptive immune cells in BC that will contribute to establishing new and promising therapeutic options, while reviewing the immunotherapies currently in use in bladder cancer.

Regulatory T cells in immune checkpoint blockade antitumor therapy

Regulatory T cells (Tregs), an essential component of the human immune system, are a heterogeneous group of T lymphocytes with the ability to suppress immune responses and maintain immune homeostasis. Recent evidence indicates that Tregs may impair antitumor immunity and facilitate cancer progression by weakening functions of effector T cells (Teffs). Consequently, targeting Tregs to eliminate them from tumor microenvironments to improve Teffs' activity could emerge as an effective strategy for cancer immunotherapy. This review outlines the biology of Tregs, detailing their origins, classification, and crucial markers. Our focus lies on the complex role of Tregs in cancer's development, progression and treatment, particularly on their suppressive role upon antitumor responses via multiple mechanisms. We delve into Tregs' involvement in immune checkpoint blockade (ICB) therapy, their dual effect on cancer immunotherapy and their potential biomarkers for ICB therapy effectiveness. We also summarize advances in the therapies that adjust Tregs to optimize ICB therapy, which may be crucial for devising innovative cancer treatment strategies.

A CD25×TIGIT bispecific antibody induces anti-tumor activity through selective intratumoral Treg cell depletion

Intratumoral regulatory T cells (Tregs) express high levels of CD25 and TIGIT, which are also recognized as markers of effector T cell (Teff) activation. Targeting these molecules each alone with monoclonal antibodies (mAbs) poses a risk of concurrently depleting both Teffs and peripheral Tregs, thereby compromising the effectiveness and selectivity of intratumoral Treg depletion. Here, leveraging the increased abundance of CD25+ TIGIT+ double-positive Tregs in the solid tumor microenvironment (but not in peripheral tissues), we explore the feasibility of using a CD25×TIGIT bispecific antibody (bsAb) to selectively deplete intratumoral Tregs. We initially constructed a bsAb co-targeting mouse CD25 and TIGIT, NSWm7210, and found that NSWm7210 conferred enhanced intratumoral Treg depletion, Teff activation, and tumor suppression as compared to the parental monotherapies in mouse models. We subsequently constructed a bsAb co-targeting human CD25 and TIGIT (NSWh7216), which preferentially eliminated CD25+ TIGIT+ double-positive cells over single-positive cells in vitro. NSWh7216 exhibited enhanced anti-tumor activity without toxicity of peripheral Tregs in CD25 humanized mice compared to the parental monotherapies. Our study illustrates the use of CD25×TIGIT bsAbs as effective agents against solid tumors based on selective depletion of intratumoral Tregs.

Molecular and modular intricacies of precision oncology

Precision medicine is revolutionizing the world in combating different disease modalities, including cancer. The concept of personalized treatments is not new, but modeling it into a reality has faced various limitations. The last decade has seen significant improvements in incorporating several novel tools, scientific innovations and governmental support in precision oncology. However, the socio-economic factors and risk-benefit analyses are important considerations. This mini review includes a summary of some commendable milestones, which are not just a series of successes, but also a cautious outlook to the challenges and practical implications of the advancing techno-medical era.

The frontier of neoadjuvant therapy in non-small cell lung cancer beyond PD-(L)1 agents

INTRODUCTION

While surgical resection is the cornerstone of treatment for resectable lung cancer, neoadjuvant/adjuvant chemotherapy has shown limited improvement in survival rates over the past decades. With the success of immune checkpoint inhibitors (ICIs) in advanced NSCLC, there is growing interest in their application in earlier stages of the disease. Recent approvals for neoadjuvant/adjuvant ICIs in stage II-IIIA NSCLC highlight this shift in treatment paradigms.

AREAS COVERED

In this review, we aim to explore available data regarding alternative agents beyond the PD-(L)1 inhibitors, such as monoclonal antibodies against CTLA4, LAG3, TIGIT, antiangiogenic drugs, and novel therapies (antibody drug conjugates, bispecific antibodies) in neoadjuvant/perioperative regimens.

EXPERT OPINION

Novel agents and combinations (with or without ICI or/and chemotherapy), guided by molecular profiling and immune phenotyping, showed promise in improving surgical and survival outcomes. Crucial is, also in early setting, to identifying biomarkers predictive of treatment efficacy in order to personalize neoadjuvant/perioperative treatment strategies.

Novel Immune Checkpoint Inhibitor Targets in Advanced or Metastatic Renal Cell Carcinoma: State of the Art and Future Perspectives

Immune checkpoint inhibitors (ICI) have become the cornerstone of treatment in renal cell carcinoma (RCC), for both metastatic disease and in an adjuvant setting. However, an adaptive resistance from cancer cells may arise during ICI treatment, therefore many studies are focusing on additional immune checkpoint inhibitor pathways. Promising targets of immunotherapeutic agents under investigation include T cell immunoglobulin and ITIM domain (TIGIT), immunoglobulin-like transcript 4 (ILT4), lymphocyte activation gene-3 (LAG-3), vaccines, T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), and chimeric antigen receptor (CAR) T cells. In this review of the literature, we recollect the current knowledge of the novel treatment strategies in the field of immunotherapy that are being investigated in RCC and analyze their mechanism of action, their activity and the clinical studies that are currently underway.

Prognostic impact of nectin-like molecule-5 (CD155) expression in non-small cell lung cancer

BACKGROUND

CD155 is a transmembrane protein that inhibits antitumor immune response and represents a predictor of worse prognosis in non-small-cell lung cancer (NSCLC). However, it remains unexplored its association with clinical characteristics and genomic status of Latin American patients. This study characterizes the CD155 expression and its clinical implications in this population.

METHODS

Tissue biopsies from 86 patients with locally-advanced or metastatic NSCLC were assessed for CD155 protein expression, ALK rearrangements and EGFR mutations. Cutoff values for high CD155 expression (CD155high) were determined from receiver operating characteristic (ROC) curves according to 2-year survival. It was evaluated its association with clinicopathological features, median progression-free survival (mPFS) and overall survival (mOS).

RESULTS

the cutoff score for CD155high was 155 in the entire cohort and in patients without oncogenic alterations, and it was 110 in patients with oncogenic alterations. Eighty-four patients (97.7%) were CD155 positive, of which fifty-six (65.0%) had CD155high. EGFR L858R mutation related to lower CD155 IHC score than exon 19 deletion. Individuals with CD155high showed a shorter mOS (13.0 vs. 30.8 months; HR: 1.96 [95% CI, 1.15-3.35]; p = 0.014). Patients without oncogenic alterations having a CD155high displayed shorter mPFS (1.6 vs. 6.4 months, HR: 2.09 [95% CI, 1.06-4.20]; p = 0.034) and mOS (2.9 vs. 23.1 months; HR: 1.27 [95% CI, 1.07- 4.42]; p = 0.032). Patients with oncogenic alterations having CD155high only showed a trend to shorter mOS (26.3 vs. 52.0 months; HR: 2.39 [95% CI, 0.98-5.83]; p = 0.058).

CONCLUSION

CD155high is a predictor of worse outcomes in patients with advanced NSCLC, predominantly among those without oncogenic alterations. CD155 could be a potential biomarker and a molecular target in patients with poor responses to current therapies.

Increased PVR Expression on Bone Marrow Macrophages May Promote Resistance to TIGIT Blockade in Multiple Myeloma

PURPOSE

TIGIT blockade in our ex vivo model of bone marrow (BM) reduced the number of malignant plasma cells (PC) in only half of patients with multiple myeloma. Here, we wanted to investigate whether increased expression of TIGIT ligands may inhibit T-cell immune response promoting resistance to TIGIT blockade.

EXPERIMENTAL DESIGN

We first characterized the number and phenotype of BM macrophages in different stages of the disease by multiparameter flow cytometry. We assessed the effect of TIGIT ligands on PC survival by performing experiments in the ex vivo BM model and analyzed changes in gene expression by using NanoString technology and real-time PCR.

RESULTS

The frequency of BM macrophages was significantly decreased in multiple myeloma, which was accompanied by changes in their immunophenotype. Moreover, we found a higher number of malignant PC in ex vivo BM cells cultured onto the poliovirus receptor (PVR) and nectin-2 compared with control, suggesting that both ligands may support PC survival. In addition, the presence of PVR, but not nectin-2, overcame the therapeutic effect of TIGIT blockade or exogenous IL2. Furthermore, exogenous IL2 increased TIGIT expression on both CD4+ and CD8+ T cells and, indirectly, PVR on BM macrophages. Consistently, PVR reduced the number of cytotoxic T cells and promoted a gene signature with reduced effector molecules.

CONCLUSIONS

IL2 induced TIGIT on T cells in the BM, in which increased PVR expression resulted in cytotoxic T-cell inhibition, promoting PC survival and resistance to TIGIT blockade.

Harnessing the Power of NK Cell Receptor Engineering as a New Prospect in Cancer Immunotherapy

Natural killer (NK) cells have recently gained popularity as an alternative for cancer immunotherapy. Adoptive cell transfer employing NK cells offers a safer therapeutic option compared to T-cell-based therapies, due to their significantly lower toxicity and the availability of diverse autologous and allogeneic NK cell sources. However, several challenges are associated with NK cell therapies, including limited in vivo persistence, the immunosuppressive and hostile tumor microenvironment (TME), and the lack of effective treatments for solid tumors. To address these limitations, the modification of NK cells to stably produce cytokines has been proposed as a strategy to enhance their persistence and proliferation. Additionally, the overexpression of activating receptors and the blockade of inhibitory receptors can restore the NK cell functions hindered by the TME. To further improve tumor infiltration and the elimination of solid tumors, innovative approaches focusing on the enhancement of NK cell chemotaxis through the overexpression of chemotactic receptors have been introduced. This review highlights the latest advancements in preclinical and clinical studies investigating the engineering of activating, inhibitory, and chemotactic NK cell receptors; discusses recent progress in cytokine manipulation; and explores the potential of combining the chimeric antigen receptor (CAR) technology with NK cell receptors engineering.

Advancements in nuclear imaging using radiolabeled nanobody tracers to support cancer immunotherapy

The evolving landscape of cancer immunotherapy has revolutionized cancer treatment. However, the dynamic tumor microenvironment has led to variable clinical outcomes, indicating a need for predictive biomarkers. Noninvasive nuclear imaging, using radiolabeled modalities, has aided in patient selection and monitoring of their treatment response. This approach holds promise for improving diagnostic accuracy, providing a more personalized treatment regimen, and enhancing the clinical response. Nanobodies or single-domain antibodies, derived from camelid heavy-chain antibodies, allow early timepoint detection of targets with high target-to-background ratios. To date, a plethora of nanobodies have been developed for nuclear imaging of tumor-specific antigens, immune checkpoints, and immune cells, both at a preclinical and clinical level. This review comprehensively outlines the recent advancements in nanobody-based nuclear imaging, both on preclinical and clinical levels. Additionally, the impact and expected future advancements on the use of nanobody-based radiopharmaceuticals in supporting cancer diagnosis and treatment follow-up are discussed.

A non-comparative, randomized, phase II trial of atezolizumab or atezolizumab plus tiragolumab for programmed death-ligand 1-positive recurrent cervical cancer (SKYSCRAPER-04)

OBJECTIVE

To evaluate tiragolumab (anti-TIGIT) and atezolizumab (anti-PD-L1) as second- or third-line therapy for PD-L1-positive persistent/recurrent cervical cancer.

METHODS

In the open-label, non-comparative, randomized phase II SKYSCRAPER-04 trial (NCT04300647), patients with PD-L1-positive (SP263 tumor area positivity ≥5%) recurrent/persistent cervical cancer after 1-2 chemotherapy lines (≥1 platinum-based) were randomized 3:1 to atezolizumab 1200 mg with/without tiragolumab 600 mg every 3 weeks until disease progression or unacceptable toxicity. Stratification factors were performance status, prior (chemo)radiotherapy, and disease status. The primary endpoint was independent review committee-assessed confirmed objective response rate per RECIST v1.1 in patients receiving tiragolumab plus atezolizumab. An objective response rate ≥21% (one-sample z-test p≤0.0245) was required for statistical significance versus a historical reference.

RESULTS

Protocol-defined independent review committee-assessed objective response rates were 19.0% (95% CI 12.6 to 27.0) in 126 patients receiving tiragolumab plus atezolizumab (p=0.0787 vs historical reference) and 15.6% (95% CI 6.5 to 29.5) in 45 atezolizumab-treated patients. Response rates were higher in PD-L1high (tumor area positivity ≥10%) than PD-L1low (tumor area positivity 5%-9%) subgroups with both regimens. At 8.5 months' median follow-up, independent review committee-assessed progression-free survival was 2.8 months (95% CI 1.7 to 4.1) with tiragolumab plus atezolizumab and 1.9 months (95% CI 1.5 to 3.0) with atezolizumab. In post hoc analyses (10.4 months' median follow-up), median overall survival was 11.1 months (95% CI 9.6 to 14.5) with the combination and 10.6 months (95% CI 6.9 to 13.8) with atezolizumab (crossover permitted). In the combination group, 3% of patients had adverse events requiring treatment discontinuation and 8% had grade ≥3 adverse events of special interest; corresponding values in the single-agent arm were 4% and 11%. There were no treatment-related deaths or new safety findings.

CONCLUSION

The objective response rate with the tiragolumab-plus-atezolizumab combination was numerically higher than the historical reference but did not reach statistical significance.

Pharmacotherapy for cervical cancer: current standard of care and new perspectives

INTRODUCTION

Cervical cancer, while highly preventable, remains an international public health challenge especially in under resourced regions. Although early-stage cervix confined cancers are often amenable to surgical resection, larger tumors deemed locally advanced cervical cancer (LACC) necessitate systemic therapy as part of chemoradiation therapy. Moreover, systemic therapy is the standard therapeutic approach for those presenting with primary metastasis or recurrence.

AREAS COVERED

While several agents have been approved to treat recurrent cervical cancer including checkpoint inhibitors as well as both biomarker agnostic and specific antibody drug conjugates, the development of agents added to chemoradiation has been less fruitful. Until recently, the addition of novel therapies to chemoradiation has been negative in terms of improving outcomes; however, results of a recent Phase III clinical trial (NCT04221945) in LACC demonstrated that the addition of pembrolizumab to standard of care chemoradiation was associated with an improvement in progression-free survival and resulted in an FDA approval for this therapy. This observation led to the first change in treating LACC since the early 2000s.

EXPERT OPINION

Improvements in systemic therapy both alone and in combination with chemoradiation for cervical cancer have been realized. Ongoing research is needed for therapeutic options following immunotherapy.

Illuminating immunotherapy response via precision T cell-targeted PET imaging

Traditionally, immunotherapy agent selection and treatment strategies are guided by biopsy-based histological information. However, biopsies are limited in that they are invasive, provide static information regarding the tumor immune microenvironment, and only sample a small part of one tumor site. The tumor microenvironment is dynamic and heterogenous. As a result, the immune milieu at one site may be distinct from other metastatic sites. These factors make identifying which patients are likely to respond to different immunotherapies and which harbor intrinsic resistance mechanisms difficult to identify based on a biopsy alone. As such, there is significant interest in alternative methodologies that better characterize the tumor immune microenvironment and monitor immunotherapy response. PET imaging potentially offers a non-invasive way to characterize the tumor immune microenvironment at the primary tumor and metastases and allow for longitudinal characterization. Herein, we review pre-clinically and clinically tested T cell-targeted PET radiopharmaceuticals, as T cells have been the dominant immunotherapy target, and their utility in both evaluating response to immunotherapy and in understanding the systemic immune response to treatment with immunotherapeutics.

Lipid-based nanosystems: the next generation of cancer immune therapy

Immunotherapy has become an important part of the oncotherapy arsenal. Its applicability in various cancer types is impressive, as well as its use of endogenous mechanisms to achieve desired ends. However, off-target or on-target-off-tumor toxicity, limited activity, lack of control in combination treatments and, especially for solid tumors, low local accumulation, have collectively limited clinical use thereof. These limitations are partially alleviated by delivery systems. Lipid-based nanoparticles (NPs) have emerged as revolutionary carriers due to favorable physicochemical characteristics, with specific applications and strengths particularly useful in immunotherapeutic agent delivery. The aim of this review is to highlight the challenges faced by immunotherapy and how lipid-based NPs have been, and may be further utilized to address such challenges. We discuss recent fundamental and clinical applications of NPs in a range of areas and provide a detailed discussion of the main obstacles in immune checkpoint inhibition therapies, adoptive cellular therapies, and cytokine therapies. We highlight how lipid-based nanosystems could address these through either delivery, direct modulation of the immune system, or targeting of the immunosuppressive tumor microenvironment. We explore advanced and emerging liposomal and lipid nanoparticle (LNP) systems for nucleic acid delivery, intrinsic and extrinsic stimulus-responsive formulations, and biomimetic lipid-based nanosystems in immunotherapy. Finally, we discuss the key challenges relating to the clinical use of lipid-based NP immunotherapies, suggesting future research directions for the near term to realize the potential of these innovative lipid-based nanosystems, as they become the crucial steppingstone towards the necessary enhancement of the efficacy of immunotherapy.

Acute Eosinophilic Pneumonia Induced by Immune Checkpoint Inhibitor and Anti-TIGIT Therapy

BACKGROUND Immune checkpoint inhibitors (ICIs) have been linked to various immune-related adverse events, including pneumonitis, necessitating early recognition and potential treatment discontinuation. Acute eosinophilic pneumonia (AEP) induced by ICIs, particularly with no reported cases involving anti-TIGIT therapy, is rare. This report describes a case of AEP following treatment with pembrolizumab and anti-TIGIT therapy. CASE REPORT A 46-year-old woman with lung adenoid cystic carcinoma and chronic hypoxemic respiratory failure on long-term oxygen therapy presented with fever, cough, and shortness of breath. She underwent left pneumonectomy and radiation therapy at diagnosis 9 years earlier. She was participating in a clinical trial using pembrolizumab and anti-TIGIT EOS-448, due to cancer progression. After starting therapy, she developed stable peripheral eosinophilia and a skin rash, suggestive of a drug reaction. On admission, she was in acute-on-chronic hypoxemic respiratory failure, febrile, with an elevated eosinophil count and new multifocal infiltrates in the right lung. Despite broad antibiotics coverage for pneumonia, she developed worsening respiratory symptoms and eosinophilia. She was then empirically started on intravenous methylprednisolone for acute eosinophilic pneumonia without confirmatory bronchoscopy as she was at high risk with her previous pneumonectomy. She subsequently had rapid improvement in her symptoms. CONCLUSIONS AEP should be considered in patients treated with ICIs who develop immune-related adverse effects. Although bronchoscopy findings are part of AEP's diagnostic criteria, this case underscores the importance of clinical judgment in the prompt initiation of steroids, even without confirmatory bronchoscopy, in rapidly progressing cases. The role of anti-TIGIT therapy in this context remains uncertain.

Radiation and systemic immunotherapy for metastatic uveal melanoma: a clinical retrospective review

Introduction

Metastatic uveal melanoma (mUM) is a difficult to treat disease. The liver is the primary site of metastasis in most patients, though uveal melanoma spreads widely in advanced disease. The only FDA approved immunotherapy medication for metastatic uveal melanoma is the HLA-A02:01 restricted bispecific T cell engager drug, Tebentafusp. Checkpoint inhibitor strategies and combination approaches have been tried with some limited success. We describe our experience treating patients at the University of Minnesota.

Methods

Patients were included if they had biopsy-confirmed mUM. Twenty-five (25) patients meeting the criteria were identified. Medical records were reviewed and data extracted for patient baseline characteristics and response to treatments.

Results

Median time to metastasis from the time of local therapy to the eye was 14.2 months (IQR; 9.3-22.0), and first site of metastasis was liver in 92% of patients. Two patients (8%) did not receive systemic therapy or radiation therapy for metastatic disease. Twenty-three (92%) patients received systemic therapy, 13 patients (52%) received ipilimumab-nivolumab as the first-line, while 4 patients (16%) received pembrolizumab. Landmark survival analysis by receipt of systemic therapy and radiation therapy treatments within 6 months of biopsy confirmed diagnosis is shown. Twenty patients (80%) received systemic therapy within 6 months of mUM diagnosis. Thirteen patients (52%) received liver directed radiation therapy within 6 months of mUM diagnosis.

Discussion

Within our cohort, there was no overall survival benefit for patients receiving treatment of metastatic disease within 6 months of mUM diagnosis, versus those electing later or no treatment at all. There was remarkable clinical activity of ipilimumab and nivolumab in a subset of patients with mUM, in agreement with prior studies, and metastatic PD-L1 positive tumors were associated with a prolonged survival.

Dysregulation of peripheral and intratumoral KLRG1+ CD8+T cells is associated with immune evasion in patients with non-small-cell lung cancer

OBJECTIVES

Killer cell lectin like receptor G1 (KLRG1) is identified as a co-inhibitory receptor for NK cells and antigen-experienced T cells. The role of KLRG1 in immune regulation in patients with non-small cell lung cancer (NSCLC) remains poorly understood.

MATERIALS AND METHODS

We measured the proportion and immune function of KLRG1+CD8+T cells derived from peripheral blood in patients with NSCLC by flow cytometry. Besides, using data from the gene expression profiles and single-cell sequencing, we explored the expression and immune role of KLRG1 in tumor tissues of patients with NSCLC. We further determined the prognostic value of KLRG1 in terms of overall survival (OS) in NSCLC patients.

RESULTS

We found that the proportion of KLRG1+CD8+T cells in peripheral blood significantly increased in patients with NSCLC as compared to those with benign pulmonary nodules and healthy donors. Peripheral KLRG1+CD8+T cell proportion was increased in elder subjects compared to that in younger ones, implying an immunosenescence phenotype. Moreover, the KLRG1+CD8+T cell levels were positively correlated with tumor size and TNM stage in the NSCLC cohort. In vitro stimulation experiments demonstrated that the KLRG1+CD8+T cells from peripheral blood expressed higher levels of Granzyme B and perforin than the KLRG1-CD8+ T cells. However, single-cell RNA sequencing data revealed that the KLRG1+CD8+ T cells were less infiltrated in tumor microenvironment and exhibited impaired cytotoxicity. The KLRG1 gene expression levels were significantly lower in tumor tissues than that in normal lung tissues, and were inversely correlated with CDH1 expression levels. Moreover, higher expression of CDH1 in tumor tissues predicted worse overall survival only in patients with KLRG1-high expression, but not in the KLRG1-low subset.

CONCLUSION

This study demonstrates that KLRG1+CD8+T cells were associated with tumor immune evasion in NSCLC and suggests KLRG1 as a potential immunotherapy target.

From bench to bedside: the past, present and future of IL-21 immunotherapy

As immunotherapy gains momentum as a promising approach for treating several types of cancer, IL-21 has emerged as the latest discovery within the γ chain cytokine family, known for its decisive effects on innate and adaptive immunity and immunopathology. Through the modulation of immune cells, IL-21 has demonstrated significant anti-tumor effects in preclinical studies. The potential of IL-21 in cancer treatment has been explored in phase I and II clinical trials, where it has been utilized both as monotherapy and in combination with other drug agents. Further investigation, alongside larger studies, is necessary before final evaluation and application of IL-21 as immunotherapy. This review aims to summarize these pre-clinical and clinical studies and to discuss the possible future directions of IL-21 immunotherapy development. Such a study may be helpful to accelerate the process of clinical application for IL21 immunotherapy.

[Research Progress on Predictive Biomarkers of Immunotherapy Efficacy in Non-small Cell Lung Cancer]

Lung cancer is one of the most common malignant tumors in the world, of which non-small cell lung cancer (NSCLC) is the majority. The emergence of immune checkpoint inhibitors (ICIs) has greatly changed the treatment strategy of NSCLC and improved the prognosis of patients. However, in reality, only a small number of patients can achieve long-term benefit. Therefore, the identification of reliable predictive biomarkers is essential for the selection of treatment modalities. With the development of molecular biology and genome sequencing technology in recent years, as well as the in-depth understanding of tumor and its host immune microenvironment, research on biomarkers has emerged in an endless stream. This review focuses on the predictive biomarkers of immunotherapy efficacy in NSCLC, in order to provide some guidance for precision immunotherapy.
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Immune checkpoint inhibitors: breakthroughs in cancer treatment

Over the past two decades, immunotherapies have increasingly been considered as first-line treatments for most cancers. One such treatment is immune checkpoint blockade (ICB), which has demonstrated promising results against various solid tumors in clinical trials. Monoclonal antibodies (mAbs) are currently available as immune checkpoint inhibitors (ICIs). These ICIs target specific immune checkpoints, including cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and programmed cell death protein 1 (PD-1). Clinical trial results strongly support the feasibility of this immunotherapeutic approach. However, a substantial proportion of patients with cancer develop resistance or tolerance to treatment, owing to tumor immune evasion mechanisms that counteract the host immune response. Consequently, substantial research focus has been aimed at identifying additional ICIs or synergistic inhibitory receptors to enhance the effectiveness of anti-PD-1, anti-programmed cell death ligand 1 (anti-PD-L1), and anti-CTLA-4 treatments. Recently, several immune checkpoint molecular targets have been identified, such as T cell immunoreceptor with Ig and ITIM domains (TIGIT), mucin domain containing-3 (TIM-3), lymphocyte activation gene-3 (LAG-3), V-domain immunoglobulin suppressor of T cell activation (VISTA), B and T lymphocyte attenuator (BTLA), and signal-regulatory protein α (SIRPα). Functional mAbs targeting these molecules are under development. CTLA-4, PD-1/PD-L1, and other recently discovered immune checkpoint proteins with distinct structures are at the forefront of research. This review discusses these structures, as well as clinical progress in mAbs targeting these immune checkpoint molecules and their potential applications.

Advances in Hodgkin Lymphoma Treatment: From Molecular Biology to Clinical Practice

Classical Hodgkin Lymphoma (cHL) is a highly curable disease, but around 20% of patients experience progression or relapse after standard frontline chemotherapy regimens. Salvage regimens followed by autologous stem cell transplants represent the historical treatment approach for these cases. In the last decade, with the increasing understanding of cHL biology and tumor microenvironment role in disease course, novel molecules have been introduced in clinical practice, improving outcomes in the relapsed/refractory setting. The anti-CD30 antibody-drug conjugated brentuximab vedotin and PD-1/PD-L1 checkpoint inhibitors represent nowadays curative options for chemorefractory patients, and randomized trials recently demonstrated their efficacy in frontline immune-chemo-combined modalities. Several drugs able to modulate the patients' T-lymphocytes and NK cell activity are under development, as well as many anti-CD30 chimeric antigen receptor T-cell products. Multiple tumor aberrant epigenetic mechanisms are being investigated as targets for antineoplastic compounds such as histone deacetylase inhibitors and hypomethylating agents. Moreover, JAK2 inhibition combined with anti-PD1 blockade revealed a potential complementary therapeutic pathway in cHL. In this review, we will summarize recent findings on cHL biology and novel treatment options clinically available, as well as promising future perspectives in the field.

A novel anti-LAG-3/TIGIT bispecific antibody exhibits potent anti-tumor efficacy in mouse models as monotherapy or in combination with PD-1 antibody

We report the generation of a novel anti-LAG-3/TIGIT bispecific IgG4 antibody, ZGGS15, and evaluated its anti-tumor efficacy in mouse models as monotherapy or in combination with a PD-1 antibody. ZGGS15 exhibited strong affinities for human LAG-3 and TIGIT, with KDs of 3.05 nM and 2.65 nM, respectively. ZGGS15 has EC50s of 0.69 nM and 1.87 nM for binding to human LAG-3 and TIGIT on CHO-K1 cells, respectively. ZGGS15 competitively inhibited the binding of LAG-3 to MHC-II (IC50 = 0.77 nM) and the binding of TIGIT to CD155 (IC50 = 0.24 nM). ZGGS15 does not induce ADCC, CDC, or obvious cytokine production. In vivo results showed that ZGGS15 had better anti-tumor inhibition than single anti-LAG-3 or anti-TIGIT agents and demonstrated a synergistic effect when combined with nivolumab, with a significantly higher tumor growth inhibition of 95.80% (p = 0.001). The tumor volume inhibition rate for ZGGS15 at 2 mg/kg was 69.70%, and for ZGGS15 at 5 mg/kg plus nivolumab at 1 mg/kg, it was 94.03% (p < 0.001). Our data reveal that ZGGS15 exhibits potent anti-tumor efficacy without eliciting ADCC or CDC or causing cytokine production, therefore having a safe profile.