PI3K/AKT/mTOR and PD­1/CTLA­4/CD28 pathways as key targets of cancer immunotherapy (Review).

T cells play an important role in cancer, and energy metabolism can determine both the proliferation and differentiation of T cells. The inhibition of immune checkpoint molecules programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte associated protein 4 (CTLA-4) are a promising cancer treatment. In recent years, research on CD28 has increased. Although numerous reports involve CD28 and its downstream PI3K/AKT/mTOR signaling mechanisms in T cell metabolism, they have not yet been elucidated. A literature search strategy was used for the databases PubMed, Scopus, Web of Science and Cochrane Library to ensure broad coverage of medical and scientific literature, using a combination of keywords including, but not limited to, 'lung cancer' and 'immunotherapy'. Therefore, the present study reviewed the interaction and clinical application of the PD-1/CTLA-4/CD28 and PI3K/AKT/mTOR pathways in T cells, aiming to provide a theoretical basis for immunotherapy in clinical cancer patients.

Risk factors for relapse of immune-related pneumonitis after 6-week oral prednisolone therapy: a follow-up analysis of a phase II study.

BACKGROUND: Immune-related pneumonitis (irP) is one of the most important immune-related adverse events caused by immune checkpoint inhibitors (ICIs). After corticosteroid therapy irP frequently relapses, which can interfere with cancer therapy. However, risk factors for irP relapse are unknown. METHODS: This study was a follow-up analysis of a phase II study that evaluated 56 patients with grade ≥ 2 irP treated with oral prednisolone, 1 mg/kg/day, tapered over 6 weeks. Clinical factors including patient characteristics, blood test findings, and response to prednisolone therapy were assessed to identify risk factors for irP relapse using the Fine-Gray test. RESULTS: Among 56 patients with irP, 22 (39.3%) experienced irP relapse after 6 weeks of prednisolone therapy during the follow-up observation period. Radiographic organising pneumonia (OP) pattern and duration to irP onset ≥ 100 days from ICI initiation were determined to be significant risk factors for irP relapse in a multivariate Fine-Gray test (hazard ratio [HR] = 3.17, 95% CI 1.37-7.32, p = 0.007, and HR = 2.61, 95% CI 1.01-6.74, p = 0.048, respectively). Other patient characteristics, blood test findings, irP severity, and response to prednisolone therapy were not associated with irP relapse. CONCLUSIONS: In irP patients treated with 6-week prednisolone tapering therapy, OP pattern and duration to irP onset ≥ 100 days were associated with relapse risk. Assessment of the risk factors for irP relapse will be helpful for irP management.

Ophthalmic Immune-Related Adverse Events and Association with Survival: Results from a Real-World Database.

PURPOSE: Assessing immune-related ocular toxicities from immune checkpoint inhibitors (ICIs) is crucial, though rare. This study, utilizing real-world data, examines the occurrence of ophthalmic immune-related adverse events (irAEs) after ICI treatment and their impact on overall survival. DESIGN: A retrospective cohort study METHODS: Data were obtained from TriNetX, an aggregated electronic health records database. Patients who developed ophthalmic irAEs within 1 year after the first instance of ICI therapy were included. Participants with defined ocular toxicities 6 months before ICI treatment were excluded. Subjects were paired with controls using propensity scores derived from demographics and cancer type. A Cox proportional hazard model was used to determine hazard ratios. A Kaplan-Meier survival function was evaluated with the log-rank test based on the development of ophthalmic irAEs in a 12-month landmark analysis. RESULTS: A cohort of 41,020 patients comprising 57.4% males with a mean age of 65.2±11.9 years was included. The five most prevalent ophthalmic irAEs in this cohort were dry eye syndrome (2%), conjunctivitis (0.87%), blepharitis (0.51%), anterior uveitis (0.39%), and keratitis (0.38%). Dry eye syndrome was the most common irAE among all ICI classes. Subjects taking CTLA-4 inhibitor plus PD-1 inhibitor and CTLA-4 inhibitors had higher rates of anterior uveitis (1.39% and 1.29%, respectively) than PD-1 inhibitors (0.27%) and PD-L1 inhibitors (0.14%) within 1 year after taking ICI. After a 12-month landmark analysis, there was a significant decreased chance of survival for the following categories: any ophthalmic irAE (HR, 1.37; 95% CI, 1.20-1.56; P < 0.0001), neuro-ophthalmic irAE (HR, 1.53; 95% CI, 1.09-2.14; P = 0.0124), and cornea and ocular surface irAE (HR, 1.34; 95% CI, 1.15-1.56; P < 0.0001). CONCLUSIONS: Ophthalmic irAEs involving the anterior segment are more frequent than the posterior segment, regardless of ICI class. Ophthalmic irAEs may also portend decreased survival. This insight could help guide clinicians aggressively manage irAEs and allow patients to continue ICI therapy despite having ocular issues.

[Side effects of Immune Checkpoint Inhibitors : Diagnostics and Management-an Update]. / Nebenwirkungen von Immuncheckpoint-Inhibitoren : Diagnostik und Management ­ ein Update.

Immune checkpoint inhibitors (ICI) represent a breakthrough in cancer therapy. They are effective in various tumor entities and can be used in more and more treatment settings. This leads to an increase in the number and complexity of cases with immune-related adverse events (irAE). The most common irAE are cutaneous, gastrointestinal and endocrine side effects, whereas less common irAE include pneumonitis, nephritis, myocarditis or neurological reactions. IrAE can usually be successfully treated, mainly with corticosteroids or other immunosuppressants, but they can also result in long-term sequelae or death. The optimal management of patients with steroid-refractory or steroid-dependent side effects still remains unclear. Broad awareness of these irAE across specialties is therefore of crucial importance to ensure early diagnosis and to improve irAE management.

Cytotoxic T-lymphocyte-associated 4 protein expression is associated with a high international prognostic score in advanced-stage classical Hodgkin lymphoma.

OBJECTIVE: Twenty percent of all classical Hodgkin lymphoma (CHL) cases relapse and recur, especially in advanced stages with a high International Prognostic Score (IPS). Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is a regulatory molecule that can inhibit the immune response and is related to tumor aggressiveness. This study aimed to determine the relationship between CTLA-4 expression in advanced-stage CHL and IPS, identifying it as a potential therapy target. RESULTS: In advanced-stage CHL, the group with a high IPS exhibited significantly higher mean CTLA-4 expression compared to the group with a low IPS (p = 0.003).The group with Hb level < 10.5 g/dl, leukocyte count > 15,000/µL, lymphocyte count < 8%, albumin level < 4 g/dl, and stage 4 exhibited higher CTLA-4 expression than the other group, although only leukocyte count and stage showed statistical significance (p = 0.004 and p = 0.020). Mean CTLA-4 expression was 239.84 ± 76.36 for nodular sclerosis, 293.95 ± 147.94 for mixed cellularity, 271.4 ± 23.56 for lymphocyte depleted, and 225.2 for lymphocyte-rich subtypes. The results suggest that CTLA-4 expression is associated with adverse prognostic factors in the IPS for advanced-stage CHL, supporting the notion that immune checkpoints play a role in cancer progression.

Preclinical models of cardiotoxicity from immune checkpoint inhibitor therapy.

Immune checkpoint inhibitor (ICI) therapy represents a ground-breaking paradigm in cancer treatment, harnessing the immune system to combat malignancies by targeting checkpoints such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed cell death protein 1 (PD-1). The use of ICI therapy generates distinctive immune-related adverse events (irAEs) including cardiovascular toxicity, necessitating targeted research efforts. This comprehensive review explores preclinical models dedicated to ICI-mediated cardiovascular complications including myocarditis. Tailored preclinical models of ICI-mediated myocardial toxicities highlight the key role of CD8+ T cells, emphasizing the profound impact of immune checkpoints on maintaining cardiac integrity. Cytokines and macrophages were identified as possible driving factors in disease progression, and at the same time, initial data on possible cardiac antigens responsible are emerging. The implications of contributing factors including thoracic radiation, autoimmune disorder, and the presence of cancer itself are increasingly understood. Besides myocarditis, mouse models unveiled an accelerated progression of atherosclerosis, adding another layer for a thorough understanding of the diverse processes involving cardiovascular immune checkpoint signalling. This review aims to discuss current preclinical models of ICI cardiotoxicity and their potential for improving enhanced risk assessment and diagnostics, offering potential targets for innovative cardioprotective strategies. Lessons from ICI therapy can drive novel approaches in cardiovascular research, extending insights to areas such as myocardial infarction and heart failure.

A systematic review and meta-analysis of observational studies and uncontrolled trials reporting on the use of checkpoint blockers in patients with cancer and pre-existing autoimmune disease.

BACKGROUND: Cancer patients with autoimmune disease have been excluded from randomized trials of immune checkpoint blockers (ICBs). We conducted a systematic review of observational studies and uncontrolled trials including cancer patients with pre-existing autoimmune disease who received ICBs. METHODS: We searched 5 electronic databases through November 2023. Study selection, data collection, and quality assessment were performed independently by 2 investigators. We performed a meta-analysis to pool incidence of immune-related adverse events (irAEs), including de novo events and flares of existing autoimmune disease, hospitalizations due to irAEs, as well as deaths. RESULTS: A total of 95 studies were included (23,897 patients with cancer and preexisting autoimmune disease). The most common cancer evaluated was lung cancer (30.7 %) followed by skin cancer (15.7 %). Patients with autoimmune disease were more likely to report irAEs compared to patients without autoimmune disease (relative risk 1.3, 95 % CI 1.0 to 1.6). The pooled occurrence rate of any irAEs (flares or de novo) was 61 % (95 % CI 54 % to 68 %); that of flares was 36 % (95 % CI 30 % to 43 %), and that of de novo irAEs was 23 % (95 % CI 16 % to 30 %). Flares were mild (grade <3) in half of cases and more commonly reported in patients with psoriasis/psoriatic arthritis (39 %), inflammatory bowel disease (37 %), and rheumatoid arthritis (36 %). 32 % of the patients with irAEs required hospitalization and treatment of irAEs included corticosteroids in 72 % of the cases. The irAEs mortality rate was 0.07 %. There were no statistically significant differences in cancer response to ICBs between patients with and without autoimmune disease. CONCLUSIONS: Although more patients with pre-existing autoimmune disease had irAEs, these were mild and managed with corticosteroids in most cases, with no impact on cancer response. These results suggest that ICBs can be used in these patients, but careful monitoring is required, as over a third of the patients will experience a flare of their autoimmune disease and/or require hospitalization. These findings provide a crucial foundation for oncologists to refine their monitoring and management strategies, ensuring that the benefits of ICB therapy are maximized while minimizing its risks.

Immunotherapy for esophageal cancer: Where are we now and where can we go.

Immune checkpoint inhibitor therapy has dramatically improved patient prognosis, and thereby transformed the treatment in various cancer types including esophageal squamous cell carcinoma (ESCC) in the past decade. Monoclonal antibodies that selectively inhibit programmed cell death-1 (PD-1) activity has now become standard of care in the treatment of ESCC in metastatic settings, and has a high expectation to provide clinical benefit during perioperative period. Further, anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) monoclonal antibody has also been approved in the treatment of recurrent/metastatic ESCC in combination with anti-PD-1 antibody. Well understanding of the existing evidence of immune-based treatments for ESCC, as well as recent clinical trials on various combinations with chemotherapy for different clinical settings including neoadjuvant, adjuvant, and metastatic diseases, may provide future prospects of ESCC treatment for better patient outcomes.

Programmed Death 1 and Cytotoxic T-Lymphocyte-Associated Protein 4 Gene Expression in Peripheral Blood Mononuclear Cells Can Serve as Prognostic Biomarkers for Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a highly aggressive form of liver cancer with poor prognosis. The lack of reliable biomarkers for early detection and accurate diagnosis and prognosis poses a significant challenge to its effective clinical management. In this study, we investigated the diagnostic and prognostic potential of programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) expression in peripheral blood mononuclear cells (PBMCs) in HCC. PD-1 and CTLA-4 gene expression was analyzed comparatively using PBMCs collected from HCC patients and healthy individuals. The results revealed higher PD-1 gene expression levels in patients with multifocal tumors, lymphatic invasion, or distant metastasis than those in their control counterparts. However, conventional serum biomarkers of liver function do not exhibit similar correlations. In conclusion, PD-1 gene expression is associated with OS and PFS and CTLA-4 gene expression is associated with OS, whereas the serum biomarkers analyzed in this study show no significant correlation with survival in HCC. Hence, PD-1 and CTLA-4 expressed in PBMCs are considered potential prognostic biomarkers for patients with HCC that can facilitate prediction of malignancy, response to currently available HCC treatments, and overall survival.

Preclinical imaging evaluation of a bispecific antibody targeting hPD1/CTLA4 using humanized mice.

BACKGROUND: The lack of an efficient way to screen patients who are responsive to immunotherapy challenges PD1/CTLA4-targeting cancer treatment. Immunotherapeutic efficacy cannot be clearly determined by peripheral blood analyses, tissue gene markers or CT/MR value. Here, we used a radionuclide and imaging techniques to investigate the novel dual targeted antibody cadonilimab (AK104) in PD1/CTLA4-positive cells in vivo. METHODS: First, humanized PD1/CTLA4 mice were purchased from Biocytogen Pharmaceuticals (Beijing) Co., Ltd. to express hPD1/CTLA4 in T-cells. Then, mouse colon cancer MC38-hPD-L1 cell xenografts were established in humanized mice. A bispecific antibody targeting PD1/CTLA4 (AK104) was labeled with radio-nuclide iodine isotopes. Immuno-PET/CT imaging was performed using a bispecific monoclonal antibody (mAb) probe 124I-AK104, developed in-house, to locate PD1+/CTLA4+ tumor-infiltrating T cells and monitor their distribution in mice to evaluate the therapeutic effect. RESULTS: The 124I-AK104 dual-antibody was successfully constructed with ideal radiochemical characteristics, in vitro stability and specificity. The results of immuno-PET showed that 124I-AK104 revealed strong hPD1/CTLA4-positive responses with high specificity in humanized mice. High uptake of 124I-AK104 was observed not only at the tumor site but also in the spleen. Compared with PD1- or CTLA4-targeting mAb imaging, 124I-AK104 imaging had excellent standard uptake values at the tumor site and higher tumor to nontumor (T/NT) ratios. CONCLUSIONS: The results demonstrated the potential of translating 124I-AK104 into a method for screening patients who benefit from immunotherapy and the efficacy, as well as the feasibility, of this method was verified by immuno-PET imaging of humanized mice.

B Cell Subsets and Immune Checkpoint Expression in Patients with Chronic Lymphocytic Leukemia.

Chronic lymphocytic leukemia (CLL) is characterized by dysfunctional B cells. Immune checkpoint molecules such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed death-1 (PD-1) are upregulated in patients with CLL and may correlate with prognostic markers such as beta-2 microglobulin (B2M). The aim of this study was to evaluate the levels of immune checkpoints on B cell subsets and to further correlate them with B2M levels in patients with CLL. We recruited 21 patients with CLL and 12 controls. B cell subsets and the levels of immune checkpoint expression were determined using conventional multi-color flow cytometry. Basal levels of B2M in patients with CLL were measured using an enzyme-linked immunosorbent assay. Patients with CLL had increased levels of activated B cells when compared to the control group, p < 0.001. The expression of PD-1 and CTLA-4 were increased on activated B cells and memory B cells, p < 0.05. There were no associations between B2M levels and the measured immune checkpoints on B cell subsets, after adjusting for sex and age. In our cohort, the patients with CLL expressed elevated levels of PD-1 and CTLA-4 immune checkpoints on activated and memory B cell subsets. However, there was no correlation between these immune checkpoint expressions and B2M levels.

The Use of Immune Regulation in Treating Head and Neck Squamous Cell Carcinoma (HNSCC).

Immunotherapy has emerged as a promising new treatment modality for head and neck cancer, offering the potential for targeted and effective cancer management. Squamous cell carcinomas pose significant challenges due to their aggressive nature and limited treatment options. Conventional therapies such as surgery, radiation, and chemotherapy often have limited success rates and can have significant side effects. Immunotherapy harnesses the power of the immune system to recognize and eliminate cancer cells, and thus represents a novel approach with the potential to improve patient outcomes. In the management of head and neck squamous cell carcinoma (HNSCC), important contributions are made by immunotherapies, including adaptive cell therapy (ACT) and immune checkpoint inhibitor therapy. In this review, we are focusing on the latter. Immune checkpoint inhibitors target proteins such as programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) to enhance the immune response against cancer cells. The CTLA-4 inhibitors, such as ipilimumab and tremelimumab, have been approved for early-stage clinical trials and have shown promising outcomes in terms of tumor regression and durable responses in patients with advanced HNSCC. Thus, immune checkpoint inhibitor therapy holds promise in overcoming the limitations of conventional therapies. However, further research is needed to optimize treatment regimens, identify predictive biomarkers, and overcome potential resistance mechanisms. With ongoing advancements in immunotherapy, the future holds great potential for transforming the landscape of oral tumor treatment and providing new hope for patients.

Incidence of Hyper Progressive Disease in Combination Immunotherapy and Anti-Programmed Cell Death Protein 1/Programmed Death-Ligand 1 Monotherapy for Unresectable Hepatocellular Carcinoma.

Introduction: Programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) signaling blockade is the most effective strategy for the treatment of immune evading hepatocellular carcinoma (HCC). While immune checkpoint inhibitor has revolutionized the concept of cancer treatment, it has also led to unexpected tumor growth. Regulatory T cells express PD-1 and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) receptors, which are proliferated and activated by antibody binding, and their ratio to CD8+ T cells is altered, which is one of the causes for hyper progressive disease (HPD). We examined the frequency of HPD in anti-PD-1/PD-L1 monotherapy and combination therapy with vascular endothelial growth factor (VEGF) antibody and anti-CTLA-4 antibodies. Methods: This was a prospective and retrospective cohort study which enrolled 198 patients with unresectable HCC from January 2015 to December 2021 at the Kindai University Hospital. Fifty-eight patients received anti-PD-1/PD-L1 monotherapy, 119 patients combination with VEGF antibody, and 21 patients combination with anti-CTLA-4 antibody. We defined HPD as tumor growth rate (TGR) ratio ≥4, ΔTGR ≥40%, and tumor growth kinetics ratio ≥4. Results: The HPD rate was 10.3% (6/58) in anti-PD-1/PD-L1 monotherapy, 1.7% (2/119) in combination with VEGF antibody, and 4.8% (1/21) in combination with anti-CTLA-4 antibody (p = 0.034). The odds ratio for HPD in the combined anti-CTLA-4 antibody group was 0.433 (95% confidence interval [CI]: 0.05-3.83) when compared to the anti-PD-1/PD-L1 monotherapy group and 2.93 (95% CI: 0.25-33.79) when compared to the combined VEGF antibody group. Conclusion: The frequency of HPD in unresectable HCC compared to anti-PD-1/PD-L1 monotherapy was decreased with the combination with anti-VEGF antibody and not increased with anti-CTLA-4 antibody. Anti-PD-1/PD-L1 combined with anti-CTLA-4 antibody is now available in real-world and needs to be further validated with accumulated clinical practice.

The future of targeting cytotoxic T-lymphocyte-associated protein-4: Is there a role?

The 2022 yearly Think Tank Meeting in Siena, Tuscany (Italy), organized by the Italian Network for Tumor Biotherapy (NIBIT) Foundation, the Parker Institute for Cancer Immunotherapy and the World Immunotherapy Council, included a focus on the future of integrating and expanding the use of targeting cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). The conference members exchanged their views on the lessons from targeting CTLA-4 and compared the effect to the impact of blocking Programmed cell death protein 1 (PD1) or its ligand (PDL1). The increasing experience with both therapeutic approaches and their combination suggests that targeting CTLA-4 may lead to more durable responses for a sizeable proportion of patients, though the specific mechanism is not entirely understood. Overcoming toxicity of blocking CTLA-4 is currently being addressed with different doses and dose regimens, especially when combined with PD1/PDL1 blocking antibodies. Novel therapeutics targeting CTLA-4 hold the promise to reduce toxicities and thus allow different combination strategies in the future. On the whole, the consent was that targeting CTLA-4 remains an important strategy to improve the efficacy of cancer immunotherapies.

Immune checkpoint biology in health & disease: Immune checkpoint biology and autoimmunity in cancer patients.

Immune checkpoints (ICs) play a central role in maintaining immune homoeostasis. The discovery that tumours use this physiological mechanism to avoid elimination by the immune system, opened up avenues for therapeutic targeting of ICs as a novel way of treating cancer. However, this therapy a new array of autoimmune side effects, termed immune-related adverse events (irAEs). In this narrative review, we first recapitulate the physiological function of ICs that are approved targets for cancer immunotherapy (CTLA-4, PD-(L)1 and LAG-3), as the groundwork to critically discuss current knowledge on irAEs. Specifically, we summarize clinical aspects and examine a molecular classification and predisposing factors of irAEs. Finally, we discuss irAE treatment, particularly emphasizing how molecular knowledge is changing the current treatment paradigm.

Tolerated Re-Challenge of Immunotherapy in a Patient with ICI Associated Myocarditis: A Case Report and Literature Review.

Many different types of cancer can be treated with immunotherapy drugs called immune checkpoint inhibitors (ICIs). These drugs have altered the landscape of cancer treatment options since they function by triggering a stronger immune response to malignancy. As expected, ICIs' modification of immune regulatory controls leads to a wide range of organ/gland-specific immune-related side effects. These adverse effects are uncommonly deadly and typically improve by discontinuing treatment or administering corticosteroid drugs. As a result of a number of factors-including a lack of specificity in the clinical presentation, the possibility of overlap with other cardiovascular and general medical illnesses, difficulties in diagnosis, and a general lack of awareness-the true incidence of ICI-associated myocarditis is likely underestimated. Currently, protocols for the surveillance, diagnosis, or treatment of this condition are unclear. Several questions remain unanswered, such as how to best screen for this rare toxin, what tests should be run on patients who are suspected of having it, how to treat myocarditis once it has developed, and who is at most risk. In this article, we provide a case study of ICI-associated myocarditis and explain its key characteristics and treatment options.

Genetic and pharmaceutical targeting of HIF1α allows combo-immunotherapy to boost graft vs. leukemia without exacerbation graft vs. host disease.

Despite potential impact on the graft vs. leukemia (GVL) effect, immunotherapy targeting CTLA-4 and/or PD-1 has not been successfully combined with bone marrow transplant (BMT) because it exacerbates graft vs. host disease (GVHD). Here, using models of GVHD and leukemia, we demonstrate that targeting hypoxia-inducible factor 1α (HIF1α) via pharmacological or genetic approaches reduces GVHD by inducing PDL1 expression on host tissue while selectively inhibiting PDL1 in leukemia cells to enhance the GVL effect. More importantly, combination of HIF1α inhibition with anti-CTLA-4 antibodies allows simultaneous inhibition of both PDL1 and CTLA-4 checkpoints to achieve better outcomes in models of mouse and human BMT-leukemia settings. These findings provide an approach to enhance the curative effect of BMT for leukemia and broaden the impact of cancer immunotherapy.

Role of DNA Methylation Profiles as Potential Biomarkers and Novel Therapeutic Targets in Head and Neck Cancer.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and is associated with high mortality. The main reasons for treatment failure are a low rate of early diagnosis, high relapse rates, and distant metastasis with poor outcomes. These are largely due to a lack of diagnostic, prognostic, and predictive biomarkers in HNSCC. DNA methylation has been demonstrated to play an important role in the pathogenesis of HNSCC, and recent studies have also valued DNA methylation as a potential biomarker in HNSCC. This review summarizes the current knowledge on DNA methylation profiles in HPV-positive and HPV-negative HNSCC and how these may contribute to the pathogenesis of HNSCC. It also summarizes the potential value of DNA methylation as a biomarker in the diagnosis, prognosis, and prediction of the response to therapy. With the recent immunotherapy era in head and neck treatment, new strategies to improve immune responses by modulating TIMEs have been intensely investigated in early-phase trials. Therefore, this study additionally summarizes the role of DNA methylation in the regulation of TIMEs and potential predictive immunotherapy response biomarkers. Finally, this study reviews ongoing clinical trials using DNA methylation inhibitors in HNSCC.

Antitumor effect of plant-produced anti-CTLA-4 monoclonal antibody in a murine model of colon cancer.

Cytotoxic T lymphocyte-associated protein 4 (CTLA-4) is an immune checkpoint regulator exclusively expressed on T cells that obstructs the cell's effector functions. Ipilimumab (Yervoy®), a CTLA-4 blocking antibody, emerged as a notable breakthrough in modern cancer treatment, showing upfront clinical benefits in multiple carcinomas. However, the exhilarating cost of checkpoint blockade therapy is discouraging and even utmost prominent in developing countries. Thereby, affordability of cancer care has become a point of emphasis in drug development pipelines. Plant expression system blossomed as a cutting-edge platform for rapid, facile to scale-up, and economical production of recombinant therapeutics. Here, we describe the production of an anti-CTLA-4 2C8 antibody in Nicotiana benthamiana. ELISA and bio-layer interferometry were used to analyze antigen binding and binding kinetics. Anticancer responses in vivo were evaluated using knocked-in mice implanted with syngeneic colon tumor. At 4 days post-infiltration, the antibody was transiently expressed in plants with yields of up to 39.65 ± 8.42 µg/g fresh weight. Plant-produced 2C8 binds to both human and murine CTLA-4, and the plant-produced IgG1 also binds to human FcγRIIIa (V158). In addition, the plant-produced 2C8 monoclonal antibody is as effective as Yervoy® in inhibiting tumor growth in vivo. In conclusion, our study underlines the applicability of plant platform to produce functional therapeutic antibodies with promising potential in cancer immunotherapy.

Re-immunotherapy with nivolumab plus ipilimumab in advanced non-small cell lung cancer patients previously treated with anti-programmed death-1 and/or anti-programmed death ligand-1 antibodies.

BACKGROUND: The role of re-immunotherapy in advanced non-small cell lung cancer (NSCLC) remains unclear. No studies have evaluated the re-immunotherapy regimen including anti-cytotoxic T-lymphocyte antigen-4 antibody for lung cancer treatment. This study aimed to investigate the efficacy and safety of re-immunotherapy with nivolumab plus ipilimumab in patients with advanced NSCLC previously treated with anti-programmed death-1 (PD-1) and/or anti-programmed death ligand-1 (PD-L1) antibodies. METHODS: We retrospectively reviewed patients with advanced or recurrent NSCLC who received immunotherapy with nivolumab plus ipilimumab (without concomitant cytotoxic chemotherapy) between November 2020 and November 2022 at the National Hospital Organization Kyoto Medical Center, Kyoto, Japan. Data were extracted from patients who had previously received immunotherapies with anti-PD-1 and/or anti-PD-L1 antibodies. Treatment responses and adverse events were evaluated. RESULTS: Of the 67 patients who received immunotherapy with nivolumab plus ipilimumab, 23 were included in final analysis. The objective response rate was 17%, and the disease control rate was 48% for nivolumab plus ipilimumab therapy. The highest grade of immune-related adverse events was grade 3, occurring in 11% of cases. CONCLUSION: Re-immunotherapy with nivolumab plus ipilimumab after anti-PD-1 and/or anti-PD-L1 immunotherapy may be feasible and provide clinical benefit in selected patients. Further prospective studies are warranted to identify the patient population that may benefit from re-immunotherapy.