Structural basis for cancer immunotherapy by the first-in-class checkpoint inhibitor ipilimumab

Real‑world evidence of advanced non‑small cell lung carcinoma treated with an immune checkpoint inhibitor plus chemotherapy

Immunotherapy is an effective treatment strategy for patients with advanced non-small cell lung cancer (NSCLC). Although clinical trials on immunotherapy have provided promising results, real-world research in clinical practice is needed to assess the effectiveness and safety of immunotherapy. The present study aimed to characterize real-world outcomes in patients with advanced NSCLC treated with immune checkpoint inhibitor (ICI)-based regimens. The medical records of patients with advanced NSCLC, who were treated with programmed cell death protein-1 (PD-1)/programmed cell death 1 ligand 1 (PD-L1) inhibitors, were reviewed for data collection. The primary objectives were to evaluate progression-free survival (PFS) and overall survival (OS). Therefore, multiple Cox regression models were used to investigate the predictive factors for survival outcomes. Furthermore, survival curves for PFS and OS were created using Kaplan-Meier estimates and compared using the log-rank test. The present study included a total of 133 patients with advanced NSCLC who received therapy with ICIs between January 1, 2019 and December 31, 2022. The final follow-up date was August 24, 2023. The median PFS and OS times were 9.8 and 27.2 months, respectively. Univariate Cox regression analysis demonstrated that sex, clinical stage, PD-L1 status, previous systemic therapy, and brain and liver metastases were associated with PFS, while Eastern Cooperative Oncology Group (ECOG) status, clinical stage, PD-L1 status and brain metastasis were associated with OS. Furthermore, multivariate Cox regression analysis demonstrated that a PD-L1 tumor proportion score (TPS) of ≥50% was an indicator of favorable PFS and OS. An ECOG performance status score of ≥1 was also associated with poor OS but not with PFS. Furthermore, brain metastasis was an indicator for poor PFS and OS, while liver metastasis was only associated with a poor PFS. Finally, the results of the present study demonstrated that PD-L1 status was an independent predictor for PFS and OS in patients with advanced NSCLC, especially adenocarcinoma, who were treated with ICIs plus chemotherapy. The results also suggested that patients with a PD-L1 TPS of ≥50% could benefit when the aforementioned regimens were administrated as a first-line or later-line therapy.

Light exacerbates local and global effects induced by pH unfolding of Ipilimumab

Monoclonal antibodies (mAbs) are an essential class of therapeutic proteins for the treatment of cancer, autoimmune and rare diseases. During their production, storage, and administration processes, these proteins encounter various stressors such as temperature fluctuations, vibrations, and light exposure, able to induce chemico-physical modifications to their structure. Viral inactivation is a key step in downstream processes, and it is achieved by titration of the mAb at low pH, followed by neutralization. The changes of the pH pose a significant risk of unfolding and subsequent aggregation to proteins, thereby affecting their manufacturing. This study aims to investigate whether a combined exposure to light during the viral inactivation process can further affect the structural integrity of Ipilimumab, a mAb primarily used in the treatment of metastatic melanoma. The biophysical and biochemical characterization of Ipilimumab revealed that pH variation is a considerable risk for its stability with irreversible unfolding at pH 2. The threshold for Ipilimumab denaturation lies between pH 2 and 3 and is correlated with the loss of the protein structural cooperativity, which is the most critical factor determining the protein refolding. Light has demonstrated to exacerbate some local and global effects making pH-induced exposed regions more vulnerable to structural and chemical changes. Therefore, specific precautions to real-life exposure to ambient light during the sterilization process of mAbs should be considered to avoid loss of the therapeutic activity and to increase the yield of production. Our findings underscore the critical role of pH optimization in preserving the structural integrity and therapeutic efficacy of mAbs. Moreover, a detailed conformational study on the structural modifications of Ipilimumab may improve the chemico-physical knowledge of this effective drug and suggest new production strategies for more stable products under some kind of stress conditions.

Novel post-translational modifications of protein by metabolites with immune responses and immune-related molecules in cancer immunotherapy

Tumour immunotherapy is an effective and essential treatment for cancer. However, the heterogeneity of tumours and the complex and changeable tumour immune microenvironment (TME) creates many uncertainties in the clinical application of immunotherapy, such as different responses to tumour immunotherapy and significant differences in individual efficacy. It makes anti-tumour immunotherapy face many challenges. Immunometabolism is a critical determinant of immune cell response to specific immune effector molecules, significantly affecting the effects of tumour immunotherapy. It is attributed mainly to the fact that metabolites can regulate the function of immune cells and immune-related molecules through the protein post-translational modifications (PTMs) pathway. This study systematically summarizes a variety of novel protein PTMs including acetylation, propionylation, butyrylation, succinylation, crotonylation, malonylation, glutarylation, 2-hydroxyisobutyrylation, β-hydroxybutyrylation, benzoylation, lactylation and isonicotinylation in the field of tumour immune regulation and immunotherapy. In particular, we elaborate on how different PTMs in the TME can affect the function of immune cells and lead to immune evasion in cancer. Lastly, we highlight the potential treatment with the combined application of target-inhibited protein modification and immune checkpoint inhibitors (ICIs) for improved immunotherapeutic outcomes.

Harnessing the capacity of phytochemicals to enhance immune checkpoint inhibitor therapy of cancers: A focus on brain malignancies

Brain cancers, particularly glioblastoma multiforme (GBM), are challenging health issues with frequent unmet aspects. Today, discovering safe and effective therapeutic modalities for brain tumors is among the top research interests. Immunotherapy is an emerging area of investigation in cancer treatment. Since immune checkpoints play fundamental roles in repressing anti-cancer immunity, diverse immune checkpoint inhibitors (ICIs) have been developed, and some monoclonal antibodies have been approved clinically for particular cancers; nevertheless, there are significant concerns regarding their efficacy and safety in brain tumors. Among the various tools to modify the immune checkpoints, phytochemicals show good effectiveness and excellent safety, making them suitable candidates for developing better ICIs. Phytochemicals regulate multiple immunological checkpoint-related signaling pathways in cancer biology; however, their efficacy for clinical cancer immunotherapy remains to be established. Here, we discussed the involvement of immune checkpoints in cancer pathology and summarized recent advancements in applying phytochemicals in modulating immune checkpoints in brain tumors to highlight the state-of-the-art and give constructive prospects for future research.

Engineered biological nanoparticles as nanotherapeutics for tumor immunomodulation

Biological nanoparticles, or bionanoparticles, are small molecules manufactured in living systems with complex production and assembly machinery. The products of the assembly systems can be further engineered to generate functionalities for specific purposes. These bionanoparticles have demonstrated advantages such as immune system evasion, minimal toxicity, biocompatibility, and biological clearance. Hence, bionanoparticles are considered the new paradigm in nanoscience research for fabricating safe and effective nanoformulations for therapeutic purposes. Harnessing the power of the immune system to recognize and eradicate malignancies is a viable strategy to achieve better therapeutic outcomes with long-term protection from disease recurrence. However, cancerous tissues have evolved to become invisible to immune recognition and to transform the tumor microenvironment into an immunosuppressive dwelling, thwarting the immune defense systems and creating a hospitable atmosphere for cancer growth and progression. Thus, it is pertinent that efforts in fabricating nanoformulations for immunomodulation are mindful of the tumor-induced immune aberrations that could render cancer nanotherapy inoperable. This review systematically categorizes the immunosuppression mechanisms, the regulatory immunosuppressive cellular players, and critical suppressive molecules currently targeted as breakthrough therapies in the clinic. Finally, this review will summarize the engineering strategies for affording immune moderating functions to bionanoparticles that tip the tumor microenvironment (TME) balance toward cancer elimination, a field still in the nascent stage.

Immune checkpoint inhibitor-induced hypophysitis with transient ACTH-dependent hypercortisolism

A woman in her 70s with metastatic melanoma presenting with refractory hypokalaemia on combined immune checkpoint inhibitors, nivolumab-ipilimumab, was diagnosed with adrenocorticotropic hormone (ACTH)-dependent hypercortisolism 11 weeks following the initiation of her immunotherapy. Investigations also demonstrated central hypothyroidism and hypogonadotropic hypogonadism. She underwent imaging studies of her abdomen and brain which revealed normal adrenal glands and pituitary, respectively. She was started on levothyroxine replacement and had close pituitary function monitoring. Two weeks later, her cortisol and ACTH levels started to trend down. She finally developed secondary adrenal insufficiency and was started on hydrocortisone replacement 4 weeks thereafter.This report highlights a case of immunotherapy-related hypophysitis with well-documented transient central hypercortisolism followed, within weeks, by profound secondary adrenal insufficiency. Healthcare professionals should remain vigilant in monitoring laboratory progression in these patients. Early recognition of the phase of hypercortisolism and its likely rapid transformation into secondary adrenal insufficiency can facilitate timely hormonal replacement and prevent complications.

Deciphering the role of alternative splicing in neoplastic diseases for immune-oncological therapies

Alternative splicing (AS) is an important molecular biological mechanism regulated by complex mechanisms involving a plethora of cis and trans-acting elements. Furthermore, AS is tissue specific and altered in various pathologies, including infectious, inflammatory, and neoplastic diseases. Recently developed immuno-oncological therapies include monoclonal antibodies (mAbs) and chimeric antigen receptor (CAR) T cells targeting, among others, immune checkpoint (ICP) molecules. Despite therapeutic successes have been demonstrated, only a limited number of patients showed long-term benefit from these therapies with tumor entity-related differential response rates were observed. Interestingly, splice variants of common immunotherapeutic targets generated by AS are able to completely escape and/or reduce the efficacy of mAb- and/or CAR-based tumor immunotherapies. Therefore, the analyses of splicing patterns of targeted molecules in tumor specimens prior to therapy might help correct stratification, thereby increasing therapy success by antibody panel selection and antibody dosages. In addition, the expression of certain splicing factors has been linked with the patients' outcome, thereby highlighting their putative prognostic potential. Outstanding questions are addressed to translate the findings into clinical application. This review article provides an overview of the role of AS in (tumor) diseases, its molecular mechanisms, clinical relevance, and therapy response.

Nanodrug Delivery Systems in Antitumor Immunotherapy

Cancer has become one of the most important factors threatening human health, and the global cancer burden has been increasing rapidly. Immunotherapy has become another clinical research hotspot after surgery, chemotherapy, and radiotherapy because of its high efficiency and tumor metastasis prevention. However, problems such as lower immune response rate and immune-related adverse reaction in the clinical application of immunotherapy need to be urgently solved. With the development of nanodrug delivery systems, various nanocarrier materials have been used in the research of antitumor immunotherapy with encouraging therapeutic results. In this review, we mainly summarized the combination of nanodrug delivery systems and immunotherapy from the following 4 aspects: (a) nanodrug delivery systems combined with cytokine therapy to improve cytokines delivery in vivo; (b) nanodrug delivery systems provided a suitable platform for the combination of immune checkpoint blockade therapy with other tumor treatments; (c) nanodrug delivery systems helped deliver antigens and adjuvants for tumor vaccines to enhance immune effects; and (d) nanodrug delivery systems improved tumor treatment efficiency and reduced toxicity for adoptive cell therapy. Nanomaterials chosen by researchers to construct nanodrug delivery systems and their function were also introduced in detail. Finally, we discussed the current challenges and future prospects in combining nanodrug delivery systems with immunotherapy.

Structural insights into IL-6 signaling inhibition by therapeutic antibodies

Antibody inhibitors of the interleukin-6 (IL-6) signaling pathway, such as tocilizumab and sarilumab, have been used to treat rheumatoid arthritis, chimeric antigen receptor T cell-induced cytokine storm, and severe COVID-19 pneumonia. Here, we solve the cryogenic electron microscopy structures of sarilumab and tocilizumab in complex with IL-6R to resolutions of 3.2 and 3.3 Å, respectively. These structures reveal that both tocilizumab and sarilumab bind to the D3 domain of IL-6R. The binding surfaces of the two antibodies largely overlap, but the detailed interactions are different. Functional studies of various mutants show results consistent with our structural analysis of the antibodies and IL-6R interactions. Structural comparisons with the IL-6/IL-6R/gp130 complex indicate that sarilumab and tocilizumab probably inhibit IL-6/IL-6R signaling by competing for the IL-6 binding site. In summary, this work reveals the antibody-blocking mechanism of the IL-6 signaling pathway and paves the way for future antibody discovery.

Soluble CTLA-4 attenuates T cell activation and modulates anti-tumor immunity

CTLA-4 is a crucial immune checkpoint receptor involved in the maintenance of immune homeostasis, tolerance, and tumor control. Antibodies targeting CTLA-4 have been promising treatments for numerous cancers, but the mechanistic basis of their anti-tumoral immune-boosting effects is poorly understood. Although the ctla4 gene also encodes an alternatively spliced soluble variant (sCTLA-4), preclinical/clinical evaluation of anti-CTLA-4-based immunotherapies have not considered the contribution of this isoform. Here, we explore the functional properties of sCTLA-4 and evaluate the efficacy of isoform-specific anti-sCTLA-4 antibody targeting in a murine cancer model. We show that expression of sCTLA-4 by tumor cells suppresses CD8+ T cells in vitro and accelerates growth and experimental metastasis of murine tumors in vivo. These effects were accompanied by modification of the immune infiltrate, notably restraining CD8+ T cells in a non-cytotoxic state. sCTLA-4 blockade with isoform-specific antibody reversed this restraint, enhancing intratumoral CD8+ T cell activation and cytolytic potential, correlating with therapeutic efficacy and tumor control. This previously unappreciated role of sCTLA-4 suggests that the biology and function of multi-gene products of immune checkpoint receptors need to be fully elucidated for improved mechanistic understanding of cancer immunotherapies.

Сytotoxic T lymphocyte-associated protein 4 (CTLA4) is overexpressed in a subset of prolactin- and growth hormone-secreting pituitary adenomas

Cytotoxic T lymphocyte-associated protein 4 (CTLA4), a negative regulator typically expressed on the surface of T lymphocytes, is targeted by immunotherapy in patients with an ever-expanding spectrum of cancers. Characterizing the expression of CTLA4 in the pituitary gland could provide additional rationale for using immune checkpoint inhibitors in pituitary adenoma patients who do not respond to conventional treatments. We assessed the expression of CTLA4 mRNA and protein in a panel of 157 human pituitary glands, 45 collected at autopsy and 112 at surgery. These specimens included 50 normal glands and 107 adenomas: 41 nonsecreting, 25 PRL-, 24 ACTH-, 11 GH-, 2 TSH-, 1 FSH-secreting, and 3 atypical. Specimens were stained for CTLA4 and adenohypophyseal hormones using RNAscope in situ hybridization, immunohistochemistry, and RNAscope Multiplex Fluorescent Assay. CTLA4 mRNA was detectable in most normal pituitary glands (48 of 50, 96%) but varied in expression, with a histological score (H-score) ranging from 0.6 to 20. The variation did not depend upon the patient's gender and age and was not significantly affected by the archival storage time. CTLA4 expression was higher (P = 0.022) in pituitary adenomas than normal glands, with the greatest levels seen in PRL- and GH-secreting adenomas (P = 0.009 and 0.023 versus normal, respectively). Eight of 25 (32%) prolactinomas and 3 of 11 (27%) GH-adenomas had an H-score greater than 20, while no differences were seen for the other types. These novel data highlight the expression of an immune checkpoint such as CTLA4 on pituitary endocrine cells, a finding that could be exploited for therapeutical applications.

Immune checkpoint inhibitors and cancer immunotherapy by aptamers: an overview

Efforts in cancer immunotherapy aim to counteract evasion mechanisms and stimulate the immune system to recognise and attack cancer cells effectively. Combination therapies that target multiple aspects of immune evasion are being investigated to enhance the overall efficacy of cancer immunotherapy. PD-1 (Programmed Cell Death Protein 1), CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4), LAG-3 (Lymphocyte-Activation Gene 3), and TIM-3 (T Cell Immunoglobulin and Mucin Domain-Containing Protein3) are all immune checkpoint receptors that play crucial roles in regulating the immune response and maintaining self-tolerance often exploited by cancer cells to evade immune surveillance. Antibodies targeted against immune checkpoint inhibitors such as anti-PD-1 antibodies (e.g., pembrolizumab, nivolumab), anti-CTLA-4 antibodies (e.g., Ipilimumab), and experimental drugs targeting LAG-3 and TIM-3, aim to block these interactions and unleash the immune system's ability to recognise and destroy cancer cells. The US FDA has approved different categories of immune checkpoint inhibitors that have been utilised successfully in some patients with metastatic melanoma, renal cell carcinoma, head and neck cancers, and non-small lung cancer. Although several immune checkpoint inhibitor antibodies have been developed, they exhibited immune-related adverse effects, resulting in hypophysitis, diabetes, and neurological issues. These adverse effects of antibodies can be reduced by developing aptamer against the target. Aptamers offer several advantages over traditional antibodies, such as improved specificity, reduced immunogenicity, and flexible design for reduced adverse effects that specifically target and block protein-protein or receptor-ligand interactions involved in immune checkpoint pathways. The current study aims to review the function of particular immune checkpoint inhibitors along with developed aptamer-mediated antitumor cytotoxicity in cancer treatment.

Deciphering the tumour immune microenvironment of hepatocellular carcinoma

Current treatments for hepatocellular carcinoma (HCC) are less effective and prone to recurrence after surgery, so it's needed to seek new ideas for its therapy. Tumour immune microenvironment (TME) is crucial for the pathogenesis, development and metastasis of HCC. Interactions between immune cells and tumour cells significantly impact responses to immunotherapies and patient prognosis. In recent years, immunotherapies for HCC have shown promising potential, but the response rate is still unsatisfactory. Understanding their cross-talks is helpful for selecting potential therapeutic targets, predicting immunotherapy responses, determining immunotherapy efficacy, identifying prognostic markers and selecting individualized treatment options. In this paper, we reviewed the research advances on the roles of immune cells and multi-omic research associated with HCC pathogenesis and therapy, and future perspectives on TME.

Combinatorial blockade for cancer immunotherapy: targeting emerging immune checkpoint receptors

The differentiation, survival, and effector function of tumor-specific CD8+ cytotoxic T cells lie at the center of antitumor immunity. Due to the lack of proper costimulation and the abundant immunosuppressive mechanisms, tumor-specific T cells show a lack of persistence and exhausted and dysfunctional phenotypes. Multiple coinhibitory receptors, such as PD-1, CTLA-4, VISTA, TIGIT, TIM-3, and LAG-3, contribute to dysfunctional CTLs and failed antitumor immunity. These coinhibitory receptors are collectively called immune checkpoint receptors (ICRs). Immune checkpoint inhibitors (ICIs) targeting these ICRs have become the cornerstone for cancer immunotherapy as they have established new clinical paradigms for an expanding range of previously untreatable cancers. Given the nonredundant yet convergent molecular pathways mediated by various ICRs, combinatorial immunotherapies are being tested to bring synergistic benefits to patients. In this review, we summarize the mechanisms of several emerging ICRs, including VISTA, TIGIT, TIM-3, and LAG-3, and the preclinical and clinical data supporting combinatorial strategies to improve existing ICI therapies.

Comparison of the profiles of first-line PD-1/PD-L1 inhibitors for advanced NSCLC lacking driver gene mutations: a systematic review and Bayesian network meta-analysis

Background

Numerous first-line immune checkpoint inhibitors (ICI) were developed for patients with advanced non-small cell lung cancer (NSCLC) lacking driver gene mutations. However, this group consists of a heterogeneous patient population, for whom the optimal therapeutic choice is yet to be confirmed.

Objective

To identify the best first-line immunotherapy regimen for overall advanced NSCLC patients and different subgroups.

Design

Systematic review and Bayesian network meta-analysis (NMA).

Methods

We searched several databases to retrieve relevant literature. We performed Bayesian NMA for the overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and treatment-related adverse events (tr-AEs) with a grade equal or more than 3 (grade ⩾ 3 tr-AEs). Subgroup analysis was conducted according to programed death ligand 1 (PD-L1) levels, histologic type, central nervous system (CNS) metastases and tobacco use history.

Results

For the PD-L1 non-selective patients, sintilimab plus chemotherapy (sinti-chemo) provided the best OS [hazard ratio (HR) = 0.59, 95% confidence interval (CI):0.42-0.83]. Nivolumab plus bevacizumab plus chemotherapy (nivo-bev-chemo) was comparable to atezolizumab plus bevacizumab plus chemotherapy (atezo-bev-chemo) in prolonging PFS (HR = 0.99, 95% CI: 0.51-1.91). Atezo-bev-chemo remarkably elevated the ORR than chemotherapy (OR = 3.13, 95% CI: 1.51-6.59). Subgroup analysis showed pembrolizumab plus chemotherapy (pembro-chemo) ranked first in OS in subgroups of PD-L1 < 1%, non-squamous, no CNS metastases, with or without smoking history, and ranked second in OS in subgroups of PD-L1 ⩾ 1% and PD-L1 1-49%. Cemiplimab and sugemalimab plus chemotherapy ranked first in OS and PFS for squamous subgroup, respectively. For patients with CNS metastases, nivolumab plus ipilimumab plus chemotherapy (nivo-ipili-chemo) and camrelizumab plus chemotherapy provided the best OS and PFS, respectively.

Conclusions

Sinti-chemo and nivo-bev-chemo were two effective first-line regimens ranked first in OS and PFS for overall patients, respectively. Pembro-chemo was favorable for patients in subgroups of PD-L1 < 1%, PD-L1 ⩾ 1%, PD-L1 1-49%, non-squamous, no CNS metastases, with or without smoking history. Addition of bevacizumab consistently provided with favorable PFS results in patients of all PD-L1 levels. Cemiplimab was the best option in squamous subgroup and nivo-ipili-chemo in CNS metastases subgroup due to their advantages in OS.

New techniques: a roadmap for the development of HCC immunotherapy

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. The absence of effective early diagnostic methods and the limitations of conventional therapies have led to a growing interest in immunotherapy as a novel treatment approach for HCC. The liver serves as an immune organ and a recipient of antigens from the digestive tract, creating a distinctive immune microenvironment. Key immune cells, including Kupffer cells and cytotoxic T lymphocytes, play a crucial role in HCC development, thus offering ample research opportunities for HCC immunotherapy. The emergence of advanced technologies such as clustered regularly interspaced short palindromic repeats (CRISPR) and single-cell ribonucleic acid sequencing has introduced new biomarkers and therapeutic targets, facilitating early diagnosis and treatment of HCC. These advancements have not only propelled the progress of HCC immunotherapy based on existing studies but have also generated new ideas for clinical research on HCC therapy. Furthermore, this review analysed and summarised the combination of current therapies for HCC and the improvement of CRISPR technology for chimeric antigen receptor T cell therapy, instilling renewed hope for HCC treatment. This review comprehensively explores the advancements in immunotherapy for HCC, focusing on the use of new techniques.

Cryoablation and Immunotherapy: An Enthralling Synergy for Cancer Treatment

As less invasive options for surgical tumor removal, minimally invasive ablative techniques have gained popularity. Several solid tumors are being treated with cryoablation, a non-heat-based ablation technique. Cryoablation data in comparison over time demonstrates better tumor response and faster recovery. Combining cryosurgery with other cancer therapies has been explored to improve the cancer-killing process. Cryoablation with the combination of immunotherapy, results in a robust and efficient attack on the cancer cells. This article focuses on investigating the ability of cryosurgery to create a strong antitumor response when combined with immunologic agents resulting in a synergetic effect. To achieve this objective, we combined cryosurgery with immunotherapy using Nivolumab and lpilimumab. Five clinical cases of lymph node, lung cancer, bone, and lung metastasis were followed and analyzed. In this series of patients, percutaneous cryoablation and addressing immunity agents were technically feasible. In the follow-ups, there appeared to be no radiological evidence of new tumor development.

Mechanisms of action of monoclonal antibodies in oncology integrated in IMGT/mAb-DB

Background

Cancer cells activate different immune checkpoint (IC) pathways in order to evade immunosurveillance. Immunotherapies involving ICs either block or stimulate these pathways and enhance the efficiency of the immune system to recognize and attack cancer cells. In this way, the development of monoclonal antibodies (mAbs) targeting ICs has significant success in cancer treatment. Recently, a systematic description of the mechanisms of action (MOA) of the mAbs has been introduced in IMGT/mAb-DB, the IMGT® database dedicated to mAbs for therapeutic applications. The characterization of these antibodies provides a comprehensive understanding of how mAbs work in cancer.

Methods

In depth biocuration taking advantage of the abundant literature data as well as amino acid sequence analyses from mAbs managed in IMGT/2Dstructure-DB, the IMGT® protein database, allowed to define a standardized and consistent description of the MOA of mAbs targeting immune checkpoints in cancer therapy.

Results

A fine description and a standardized graphical representation of the MOA of selected mAbs are integrated within IMGT/mAb-DB highlighting two main mechanisms in cancer immunotherapy, either Blocking or Agonist. In both cases, the mAbs enhance cytotoxic T lymphocyte (CTL)-mediated anti-tumor immune response (Immunostimulant effect) against tumor cells. On the one hand, mAbs targeting co-inhibitory receptors may have a functional Fc region to increase anti-tumor activity by effector properties that deplete T_reg cells (Fc-effector function effect) or may have limited FcγR binding to prevent T_eff cells depletion and reduce adverse events. On the other hand, agonist mAbs targeting co-stimulatory receptors may bind to FcγRs, resulting in antibody crosslinking (FcγR crosslinking effect) and substantial agonism.

Conclusion

In IMGT/mAb-DB, mAbs for cancer therapy are characterized by their chains, domains and sequence and by several therapeutic metadata, including their MOA. MOAs were recently included as a search criterion to query the database. IMGT® is continuing standardized work to describe the MOA of mAbs targeting additional immune checkpoints and novel molecules in cancer therapy, as well as expanding this study to other clinical domains.

Chemokine Receptors CCR6 and PD1 Blocking scFv E27 Enhances Anti-EGFR CAR-T Therapeutic Efficacy in a Preclinical Model of Human Non-Small Cell Lung Carcinoma

Chimeric antigen receptor (CAR)-T cells, a therapeutic agent for solid tumors, are not completely effective due to a lack of infiltration of T cells into the tumor site and immunity caused by Programmed Death Receptor 1(PD1). Here, an epidermal growth factor receptor (EGFR) CAR-T cell was engineered to express the chemokine receptor CCR6 and secrete PD1 blocking Single-chain antibody fragment (scFv) E27 to enhance their anti-tumor effects. The findings showed that CCR6 enhanced the migration of EGFR CAR-E27-CCR6 T cells in vitro by the Transwell migration assay. When incubated with tumor cells, EGFR CAR-E27-CCR6 T cells specifically exerted potent cytotoxicity and produced high levels of pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-2 (IL-2), and interferon-γ (IFN-γ). A non-small cell lung carcinoma (NSCLC) cell line-derived xenograft model was constructed by implanting modified A549 cell lines into immunodeficient NOD.PrkdcscidIl2rgem1/Smoc (NSG) mice. In comparison with traditional EGFR CAR-T cells, live imaging indicated that EGFR CAR-E27-CCR6 T cells displayed superior anti-tumor function. In addition, the histopathological examination of mouse organs showed no obvious organic damage. Our findings confirmed that PD1 blocking and CCR6 can enhance the anti-tumor function of EGFR CAR-T cells in an NSCLC xenograft model, providing an effective treatment strategy to improve the efficacy of CAR-T in NSCLC.

Residue-Level Characterization of Antibody Binding Epitopes Using Carbene Chemical Footprinting

Characterization of antibody binding epitopes is an important factor in therapeutic drug discovery, as the binding site determines and drives antibody pharmacology and pharmacokinetics. Here, we present a novel application of carbene chemical footprinting with mass spectrometry for identification of antibody binding epitopes at the single-residue level. Two different photoactivated diazirine reagents provide complementary labeling information allowing structural refinement of the antibody binding interface. We applied this technique to map the epitopes of multiple MICA and CTLA-4 antibodies and validated the findings with X-ray crystallography and yeast surface display epitope mapping. The characterized epitopes were used to understand biolayer interferometry-derived competitive binding results at the structural level. We show that carbene footprinting provides fast and high-resolution epitope information critical in the antibody selection process and enables mechanistic understanding of function to accelerate the drug discovery process.

Computational analysis of structural and functional evaluation of the deleterious missense variants in the human CTLA4 gene

CTLA-4 is an immune checkpoint receptor that negatively regulates the T-cell function expressed after T-cell activation to break the immune response. The current study predicted the genomic analysis to explore the functional variations of missense SNPs in the human CTLA4 gene using PolyPhen2, SIFT, PANTHER, PROVEAN, Fathmm, Mutation Assessor, PhD-SNP, SNPs&GO, SNAP2, and MutPred2. Phylogenetic conservation protein was predicted by ConSurf. Protein structural analysis was carried out by I-Mutant3, MUpro, iStable2, PremPS, and ERIS servers. Molecular dynamics trajectory analysis (RMSD, RMSF, Rg, SASA, H-bonds, and PCA) was performed to analyze the dynamic behavior of native and mutant CTLA-4 at the atomic level. Our in-silico analysis suggested that C58S, G118R, P137Q, P137R, P137L, P138T, and G146L variants were predicted to be the most deleterious missense variants and highly conserved residues. Moreover, the molecular dynamics analysis proposed a decrease in the protein stability and compactness with the P137R and P138T highlighting the impact of these variants on the function of the CTLA-4 protein.Communicated by Ramaswamy H. Sarma.

Characterization of the high-affinity anti-CTLA-4 monoclonal antibody JS007 for immune checkpoint therapy of cancer

Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) is a critical inhibitory checkpoint molecule, and monoclonal antibodies (mAbs) targeting CTLA-4 that restore anti-tumor T cell immunity have achieved clinical success. Here, we report a humanized IgG1 mAb, namely JS007, with high binding affinity to CTLA-4. JS007 shows superior binding affinity and T-cell activating efficiency over ipilimumab. Moreover, it demonstrates substantial in vivo tumor suppression efficacy at low doses. The crystal structure of JS007/CTLA-4 complex (PDB: 8HIT) shows JS007 adopts a heavy-chain-dominant binding mode, and mainly contacts the BC loop, DE loop and FG loop of CTLA-4. Notably, two Tyr residues (VH-Y100 and VL-Y32) from the complementarity-determining region loops insert into the two cavities formed by the residues from the loops of CTLA-4, which may contribute to the stabilization of the binding. Comparative analysis with other anti-CTLA-4 mAbs indicates that the double "wedge-into-hole" binding mode is unique for JS007 and may be responsible for the high-affinity binding to CTLA-4. These findings have provided an important molecular understanding of the high-affinity CTLA-4 blockade mAbs and shed light on future development of agents targeting CTLA-4.

Epitope mapping of monoclonal antibodies: a comprehensive comparison of different technologies

Monoclonal antibodies have become an important class of therapeutics in the last 30 years. Because the mechanism of action of therapeutic antibodies is intimately linked to their binding epitopes, identification of the epitope of an antibody to the antigen plays a central role during antibody drug development. The gold standard of epitope mapping, X-ray crystallography, requires a high degree of proficiency with no guarantee of success. Here, we evaluated six widely used alternative methods for epitope identification (peptide array, alanine scan, domain exchange, hydrogen-deuterium exchange, chemical cross-linking, and hydroxyl radical footprinting) in five antibody-antigen combinations (pembrolizumab+PD1, nivolumab+PD1, ipilimumab+CTLA4, tremelimumab+CTLA4, and MK-5890+CD27). The advantages and disadvantages of each technique are demonstrated by our data and practical advice on when and how to apply specific epitope mapping techniques during the drug development process is provided. Our results suggest chemical cross-linking most accurately identifies the epitope as defined by crystallography.

Progress in the cryoablation and cryoimmunotherapy for tumor

With the rapid advancement of imaging equipment and minimally invasive technology, cryoablation technology is being used more frequently in minimally invasive treatment of tumors, primarily for patients with early tumors who voluntarily consent to ablation as well as those with advanced tumors that cannot be surgically removed or cannot be tolerated. Cryoablation is more effective and secure for target lesions than other thermal ablation methods like microwave and radiofrequency ablation (RFA). The study also discovered that cryoablation, in addition to causing tumor tissue necrosis and apoptosis, can facilitate the release of tumor-derived autoantigens into the bloodstream and activate the host immune system to elicit beneficial anti-tumor immunological responses against primary. This may result in regression of the primary tumor and distant metastasis. The additional effect called " Accompanying effects ". It is the basis of combined ablation and immunotherapy for tumor. At present, there is a lot of research on the mechanism of immune response induced by cryoablation. Trying to solve the question: how positively induce immune response. In this review, we focus on: 1. the immune effects induced by cryoablation. 2. the effect and mechanism of tumor immunotherapy combined with cryoablation. 3.The clinical research of this combination therapy in the treatment of tumors.

Artificial Intelligence and Advanced Melanoma: Treatment Management Implications

Artificial intelligence (AI), a field of research in which computers are applied to mimic humans, is continuously expanding and influencing many aspects of our lives. From electric cars to search motors, AI helps us manage our daily lives by simplifying functions and activities that would be more complex otherwise. Even in the medical field, and specifically in oncology, many studies in recent years have highlighted the possible helping role that AI could play in clinical and therapeutic patient management. In specific contexts, clinical decisions are supported by "intelligent" machines and the development of specific softwares that assist the specialist in the management of the oncology patient. Melanoma, a highly heterogeneous disease influenced by several genetic and environmental factors, to date is still difficult to manage clinically in its advanced stages. Therapies often fail, due to the establishment of intrinsic or secondary resistance, making clinical decisions complex. In this sense, although much work still needs to be conducted, numerous evidence shows that AI (through the processing of large available data) could positively influence the management of the patient with advanced melanoma, helping the clinician in the most favorable therapeutic choice and avoiding unnecessary treatments that are sure to fail. In this review, the most recent applications of AI in melanoma will be described, focusing especially on the possible finding of this field in the management of drug treatments.

Human immunomodulatory ligand B7-1 mediates synaptic remodeling via the p75 neurotrophin receptor

Cell surface receptors, ligands, and adhesion molecules underlie development, circuit formation, and synaptic function of the central nervous system and represent important therapeutic targets for many neuropathologies. The functional contributions of interactions between cell surface proteins of neurons and nonneuronal cells have not been fully addressed. Using an unbiased protein-protein interaction screen, we showed that the human immunomodulatory ligand B7-1 (hB7-1) interacts with the p75 neurotrophin receptor (p75NTR) and that the B7-1:p75NTR interaction is a recent evolutionary adaptation present in humans and other primates, but absent in mice, rats, and other lower mammals. The surface of hB7-1 that engages p75NTR overlaps with the hB7-1 surface involved in CTLA-4/CD28 recognition, and these molecules directly compete for binding to p75NTR. Soluble or membrane-bound hB7-1 altered dendritic morphology of cultured hippocampal neurons, with loss of the postsynaptic protein PSD95 in a p75NTR-dependent manner. Abatacept, an FDA-approved therapeutic (CTLA-4-hFc fusion) inhibited these processes. In vivo injection of hB7-1 into the murine subiculum, a hippocampal region affected in Alzheimer's disease, resulted in p75NTR-dependent pruning of dendritic spines. Here, we report the biochemical interaction between B7-1 and p75NTR, describe biological effects on neuronal morphology, and identify a therapeutic opportunity for treatment of neuroinflammatory diseases.

Identification and validation of a potential key gene SGOL1 for poor prognosis in hepatocellular carcinoma based on a bioinformatics approach

OBJECTIVE

Hepatocellular carcinoma (HCC) is one of the most prevalent types of cancer worldwide. Shugoshin 1 (SGOL1) plays a crucial role in cell mitosis and its aberrant expression level in human tumors has shown to promote chromosomal instability (CIN) and accelerate tumor growth. SGOL1 expression level in HCC cells and tissues, whether it has an influence on HCC patients' prognosis, and its mechanism of action have not yet been studied.

METHODS

We carried out the bioinformatics analysis of SGOL1 expression level and survival analysis in 8 different malignancies, including HCC. In addition, we analyzed SGOL1 expression level in HCC tissues, as well as HCC patients' clinical features, enrichment analysis of SGOL1 function and mechanism of action in HCC and tumor immune cells. The effects of SGOL1 expression level and cell viability on HCC were confirmed by in vitro cytological assays.

RESULTS

It was found that SGOL1 mRNA expression level was significantly higher in several tumor tissues, including HCC, than in corresponding normal tissues, and the elevated SGOL1 expression level was strongly associated with HCC patients' poor prognosis. It was also revealed that SGOL1 expression level in HCC tissue was positively correlated with disease stage, tumor grade, and tumor size, and the results of multivariate logistic regression analysis showed that SGOL1 was one of the independent influential factors of the prognosis of HCC. Enrichment analysis revealed that SGOL1 expression level in HCC tissue was mainly associated with tumor proliferation, cell cycle, and other factors. The results of the immune infiltration analysis indicated that SGOL1 expression level was associated with immune cell infiltration and immune checkpoints in HCC. In vitro experiments demonstrated the high SGOL1 expression level in HCC tissues and cells, and silencing of SGOL1 resulted in altered cell cycle markers and decreased proliferation, invasion, and migration of HCC cells.

CONCLUSION

The findings revealed that SGOL1 is highly expressed in HCC tissues, it is a biomarker of a poor prognosis, which may be related to immune cell infiltration in HCC, and may enhance the proliferation, invasion, and migration of HCC cells. The results may provide new insights into targeted treatment of HCC and improve HCC patients' prognosis.

Pivotal role of PD-1/PD-L1 immune checkpoints in immune escape and cancer progression: Their interplay with platelets and FOXP3+Tregs related molecules, clinical implications and combinational potential with phytochemicals

Immune checkpoint proteins including programmed cell death protein 1 (PD-1), its ligand PD-L1 and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) are involved in proliferation, angiogenesis, metastasis, chemoresistance via immune escape and immune tolerance by disturbing cytotoxic T cell activation. Though many clinical trials have been completed in several cancers by using immune checkpoint inhibitors alone or in combination with other agents to date, recently multi-target therapy is considered more attractive than monotherapy, since immune checkpoint proteins work with other components such as surrounding blood vessels, dendritic cells, fibroblasts, macrophages, platelets and extracellular matrix within tumor microenvironment. Thus, in the current review, we look back on research history of immune checkpoint proteins and discuss their associations with platelets or tumor cell induced platelet aggregation (TCIPA) and FOXP3+ regulatory T cells (Tregs) related molecules involved in immune evasion and tumor progression, clinical implications of completed trial results and signaling networks by phytochemicals for combination therapy with immune checkpoint inhibitors and suggest future research perspectives.

Exploring the oncogenic roles of LINC00857 in pan-cancer

Although aberrant LINC00857 expression may play a key role in oncogenesis, no research has analyzed the pan-cancer oncogenic roles of LINC00857, particularly in tumor immunology. Here, we integrated data from several databases to analyze the characteristics of LINC00857 in pan-cancer. We found that LINC00857 was overexpressed and correlated with a poor prognosis in a variety of cancers. Furthermore, high-expression of LINC00857 was negatively associated with immune cell infiltration and immune checkpoint gene expression. Notably, LINC00857 expression was negatively related to microsatellite instability and tumor mutation burden in colorectal cancer, implying poor reaction to immunotherapy when LINC00857 was highly expressed. Targeting LINC00857 could dramatically impair the proliferative ability of colorectal cancer cells. After RNA-sequencing in HCT116 cells, gene set enrichment analysis showed that LINC00857 may accelerate cancer progression by inhibiting the ferroptosis pathway and promoting glycolipid metabolism in colorectal cancer. Screening by weighted gene co-expression network analysis determined PIWIL4 as a target of LINC00857, which also performed an immunosuppressive role in colorectal cancer. Based on the structure of PIWIL4, a number of small molecule drugs were screened out by virtual screening and sensitivity analysis. In summary, LINC00857 expression was closely correlated with an immunosuppressive microenvironment and may be a novel diagnostic and prognostic biomarker for diverse cancers. The LINC00857/PIWIL4 axis may be predictive biomarkers for immunotherapy and valuable molecular targets for malignant tumors.

A B7-CD28 Family-Based Signature Demonstrates Significantly Different Prognosis and Immunological Characteristics in Diffuse Gliomas

The B7-CD28 gene family plays a crucial role in modulating immune functions and has served as potential targets for immunotherapeutic strategies. Therefore, we systematically analyzed B7-CD28 family gene expression profiles and constructed a B7-CD28 family-based prognostic signature to predict survival and immune host status in diffuse gliomas. The TCGA dataset was used as a training cohort, and three CGGA datasets (mRNAseq_325, mRNAseq_693 and mRNA-array) were employed as validation cohorts to intensify the findings that we have revealed in TCGA dataset. Ultimately, we developed a B7-CD28 family-based signature that consisted of CD276, CD274, PDCD1LG2 and CD80 using LASSO Cox analysis. This gene signature was validated to have significant prognostic value, and could be used as a biomarker to distinguish pathological grade and IDH mutation status in diffuse glioma. Additionally, we found that the gene signature was significantly related to intensity of immune response and immune cell population, as well as several other important immune checkpoint genes, holding a great potential to be a predictive immune marker for immunotherapy and tumor microenvironment. Finally, a B7-CD28 family-based nomogram was established to predict patient life expectancy contributing to facilitate personalizing therapy for tumor sufferers. In summary, this is the first mathematical model based on this gene family with the aim of providing novel insights into immunotherapy for diffuse glioma.

High-throughput virtual screening of small-molecule inhibitors targeting immune cell checkpoints to discover new immunotherapeutics for human diseases

Immunotherapy is widely used to treat various cancers, and the drugs used are called immune checkpoint (ICP) inhibitors. Overexpression of immune cell checkpoints is reported for other human diseases such as acute infections (malaria), chronic viral infection (HIV, hepatitis B virus, TB infections), allergy, asthma, neurodegeneration, and autoimmune diseases. Some mAbs (monoclonal antibodies) are available against ICPs, but they have side effects. Small molecule seems to be safer in comparison with mAbs. Three independent small-molecule inhibitor libraries consisting of 9466 compounds were screened against seven immune cell checkpoints by applying high-throughput virtual screening approach. A total of 13 ICP inhibitors were finalized based on docking, MM-GBSA scores, and ADME properties. Six compounds were selected for MD simulation, and then, rutin hydrate (targeting all seven immune cell checkpoints), amikacin hydrate (targeting six), and 6-hydroxyluteolin (targeting three) were found to be the best immune cell checkpoint inhibitors. These three potential inhibitors have shown the potential to activate human immune cells and thus may control the spread of human lifestyle or infectious diseases. Proposed inhibitors warrant the in vitro and in vivo validation to develop it as an immunotherapeutic.

Evolution of Preclinical Characterization and Insights into Clinical Pharmacology of Checkpoint Inhibitors Approved for Cancer Immunotherapy

Cancer immunotherapy has significantly advanced the treatment paradigm in oncology, with approvals of immuno‐oncology agents for over 16 indications, many of them first line. Checkpoint inhibitors (CPIs) are recognized as an essential backbone for a successful anticancer therapy regimen. This review focuses on the US Food and Drug Administration (FDA) regulatory approvals of major CPIs and the evolution of translational advances since their first approval close to a decade ago. In addition, critical preclinical and clinical pharmacology considerations, an overview of the pharmacokinetic and dose/regimen aspects, and a discussion of the future of CPI translational and clinical pharmacology as combination therapy becomes a mainstay of industrial immunotherapy development and in clinical practice are also discussed.

Managing antibody stability: effects of stressors on Ipilimumab from the commercial formulation to diluted solutions

The stability of the monoclonal antibody Ipilimumab, the active ingredient of Yervoy®, used for the treatment of different types of cancer, has been investigated. Shaking/temperature, light exposure and dilution, protein drug renowned stressors, were applied on a 30-45-day series of experiments to observe the physicochemical and biological behavior of the molecule. Ipilimumab demonstrated stability under shaking and heat up to 45 days, without any unfolding during the induced combined stressors. Under artificial sunlight, the mAb showed to be sensitive even under the minimum dose tested (720 kJ/m²) with formation of aggregates, particularly when diluted in glucose solution. The light-induced soluble aggregates were higher in the case of diluted samples irradiated with much higher light doses (10460 kJ/m²). The aggregation of Ipilimumab took place also by irradiating the non-diluted formulation, indicating that the excipients did not protect completely the drug from photodegradation. Amino acid oxidation and deamidation were found. Anyway, after irradiation with both light doses, soluble Ipilimumab maintained its typical β-sheets structure, and the tertiary structure was nearly maintained compared to the dark. As an additional stressor test, the effect of dilution on the formulation was monitored by using a saline solution (1 mg/mL Ipilimumab) applied during hospital infusion. After two days from dilution, the protein exhibited aggregation and chemical modifications including oxidation and deamidation. When stability conditions were compromised, the viability of human cell lines treated with the stressed formulation slight decreased suggesting low potential biological toxicity of the modified mAb. As this study has demonstrated the susceptibility of Ipilimumab to light, specific solutions, and excipients as well as the use of safe light in manufacturing, handling, and storage of this drug should be promoted. Moreover, the use of proper primary and secondary packaging should be indicated to avoid the detrimental effect of light on the mAb structure and efficacy. A detailed understanding of Ipilimumab physicochemical properties, integrity, and stability could assure the best storage and manipulation conditions for its safe and successful application in cancer therapy.

Lysine Acetylation/Deacetylation Modification of Immune-Related Molecules in Cancer Immunotherapy

As major post-translational modifications (PTMs), acetylation and deacetylation are significant factors in signal transmission and cellular metabolism, and are modulated by a dynamic process via two pivotal categories of enzymes, histone acetyltransferases (HATs) and histone deacetylases (HDACs). In previous studies, dysregulation of lysine acetylation and deacetylation has been reported to be associated with the genesis and development of malignancy. Scientists have recently explored acetylation/deacetylation patterns and prospective cancer therapy techniques, and the FDA has approved four HDAC inhibitors (HDACi) to be used in clinical treatment. In the present review, the most recent developments in the area of lysine acetylation/deacetylation alteration in cancer immunotherapy were investigated. Firstly, a brief explanation of the acetylation/deacetylation process and relevant indispensable enzymes that participate therein is provided. Subsequently, a multitude of specific immune-related molecules involved in the lysine acetylation/deacetylation process are listed in the context of cancer, in addition to several therapeutic strategies associated with lysine acetylation/deacetylation modification in cancer immunotherapy. Finally, a number of prospective research fields related to cancer immunotherapy concepts are offered with detailed analysis. Overall, the present review may provide a reference for researchers in the relevant field of study, with the aim of being instructive and meaningful to further research as well as the selection of potential targets and effective measures for future cancer immunotherapy strategies.

Combination targeted and immune therapy in the treatment of advanced melanoma: a valid treatment option for patients?

Melanomas harboring an activating BRAFV600 mutation account for 50% of all advanced melanomas. The approval of BRAF-targeted therapy revolutionized treatment of these patients with achievement of impressive responses. However, development of resistance to these drugs is a significant problem, and as such, duration of response remains low, with median progression free survival of around 11–15 months. Immune checkpoint blockers exploit the immune system to eradicate cancer and can produce durable disease control that results in long-term, treatment-free survival in some patients. These drugs have shown very impressive survival in patients with BRAF-mutated melanoma. Thus, there is a need to continue to utilize emerging data to achieve long-term disease control for patients with advanced melanoma. Combining targeted therapy with immune therapy may be one possible way to achieve this goal. In this review, the mechanisms of action of these two pathways, including the mechanistic basis of this combination, are summarized, along with results of completed and ongoing trials in triple therapy.

Application of Noninvasive Imaging to Combined Immune Checkpoint Inhibitors for Breast Cancer: Facts and Future

With the application of mono-immunotherapy in cancer, particularly immune checkpoint inhibitors, improved outcomes have been achieved. However, there are several limitations to immunotherapy, such as a poor response to the drugs, immune resistance, and immune-related adverse events. In recent years, studies of preclinical animal models and clinical trials have demonstrated that immune checkpoint inhibitors for breast cancer can significantly prolong the overall survival and quality of patients' lives. Meanwhile, combined immune checkpoint inhibitor treatment has attracted researchers' attention and showed great potential in the comprehensive treatment of breast cancer patients. Additionally, noninvasive imaging enables physicians to predict response to combined immunotherapeutic drugs, achieve treatment efficacy, and lead to better clinical management. Herein, we review the background of combined immune checkpoint inhibitor therapy and summarize its targeted imaging as well as progress in noninvasive imaging aimed at evaluating therapeutic outcomes. Finally, we describe several factors that may influence the outcome of this combined immunotherapy, the future direction of medical imaging, and the potential application of artificial intelligence in breast cancer. With further development of noninvasive imaging for the guidance of combined immune checkpoint inhibitors, cures for this disease may be achieved.

Addressing the Elephant in the Immunotherapy Room: Effector T-Cell Priming versus Depletion of Regulatory T-Cells by Anti-CTLA-4 Therapy

Cytotoxic T-lymphocyte Associated Protein 4 (CTLA-4) is an immune checkpoint molecule highly expressed on regulatory T-cells (Tregs) that can inhibit the activation of effector T-cells. Anti-CTLA-4 therapy can confer long-lasting clinical benefits in cancer patients as a single agent or in combination with other immunotherapy agents. However, patient response rates to anti-CTLA-4 are relatively low, and a high percentage of patients experience severe immune-related adverse events. Clinical use of anti-CTLA-4 has regained interest in recent years; however, the mechanism(s) of anti-CTLA-4 is not well understood. Although activating T-cells is regarded as the primary anti-tumor mechanism of anti-CTLA-4 therapies, mounting evidence in the literature suggests targeting intra-tumoral Tregs as the primary mechanism of action of these agents. Tregs in the tumor microenvironment can suppress the host anti-tumor immune responses through several cell contact-dependent and -independent mechanisms. Anti-CTLA-4 therapy can enhance the priming of T-cells by blockading CD80/86-CTLA-4 interactions or depleting Tregs through antibody-dependent cellular cytotoxicity and phagocytosis. This review will discuss proposed fundamental mechanisms of anti-CTLA-4 therapy, novel uses of anti-CTLA-4 in cancer treatment and approaches to improve the therapeutic efficacy of anti-CTLA-4.

Cardiotoxicity risk factors with immune checkpoint inhibitors

Background

Checkpoint-inhibitor immunotherapies have had a profound effect in the treatment of cancer by inhibiting down-regulation of T-cell response to malignancy. The cardiotoxic potential of these agents was first described in murine models and, more recently, in numerous clinical case reports of pericarditis, myocarditis, pericardial effusion, cardiomyopathy, and new arrhythmias. The objective of our study was to determine the frequency of and associated risk factors for cardiotoxic events in patients treated with immune checkpoint inhibitors.

Methods

Medical records of patients who underwent immunotherapy with durvalumab, ipilimumab, nivolumab, and pembrolizumab at Wake Forest Baptist Health were reviewed. We collected retrospective data regarding sex, cancer type, age, and cardiovascular disease risk factors and medications. We aimed to identify new diagnoses of heart failure, atrial fibrillation, ventricular fibrillation/tachycardia, myocarditis, and pericarditis after therapy onset. To assess the relationship between CVD risk factors and the number of cardiac events, a multivariate model was applied using generalized linear regression. Incidence rate ratios were calculated for every covariate along with the adjusted P-value. We applied a multivariate model using logistic regression to assess the relationship between CVD risk factors and mortality. Odds ratios were calculated for every covariate along with the adjusted P-value. Adjusted P-values were calculated using multivariable regression adjusting for other covariates.

Results

Review of 538 medical records revealed the following events: 3 ventricular fibrillation/tachycardia, 12 pericarditis, 11 atrial fibrillation with rapid ventricular rate, 0 myocarditis, 8 heart failure. Significant risk factors included female gender, African American race, and tobacco use with IRR 3.34 (95% CI 1.421, 7.849; P = 0.006), IRR 3.39 (95% CI 1.141, 10.055; P = 0.028), and IRR 4.21 (95% CI 1.289, 13.763; P = 0.017) respectively.

Conclusions

Our study revealed 34 significant events, most frequent being pericarditis (2.2%) and atrial fibrillation (2.0%) with strongest risk factors being female gender, African American race, and tobacco use. Patients who meet this demographic, particularly those with planned pembrolizumab treatment, may benefit from early referral to a cardio-oncologist. Further investigation is warranted on the relationship between CTLA-4 and PD-L1 expression and cardiac adverse events with ICIs, particularly for these subpopulations.

Inborn Errors of Immunity and Their Phenocopies: CTLA4 and PD-1

Elucidating links between genotype and phenotype in patients with rare inborn errors of immunity (IEIs) provides insights into mechanisms of immune regulation. In many autosomal dominant IEIs, however, variation in expressivity and penetrance result in complex genotype-phenotype relations, while some autosomal recessive IEIs are so rare that it is difficult to draw firm conclusions. Phenocopies arise when an environmental or non-genetic factor replicates a phenotype conferred by a specific genotype. Phenocopies can result from therapeutic antibodies or autoantibodies that target a protein to replicate aspects of the phenotype conferred by mutations in the gene encoding the same protein. Here, we consider IEIs arising from rare genetic variants in CTLA4 and PDCD1 and compare clinical and laboratory manifestations arising as drug-induced phenocopies (immune related adverse events, IRAEs) in cancer patients treated with immune checkpoint inhibitors (ICI) and identify outstanding questions regarding mechanism of disease.

Biomarkers for response to immune checkpoint inhibitors in gastrointestinal cancers

Gastrointestinal (GI) cancers account for a large proportion of cancer deaths worldwide and pose a major public health challenge. Immunotherapy is considered to be one of the prominent and successful approaches in cancer treatment in recent years. Among them, immune checkpoint inhibitor (ICI) therapy, has received widespread attention, and many clinical findings support the feasibility of ICIs, with sustained responses and significantly prolonged lifespan observed in a wide range of tumors. However, patients treated with ICIs have not fully benefited, and therefore, the identification and development of biomarkers for predicting ICI treatment response have received further attention and exploration. From tumor genome to molecular interactions in the tumor microenvironment, and further expanding to circulating biomarkers and patient characteristics, the exploration of biomarkers is evolving with high-throughput sequencing as well as bioinformatics. More large-scale prospective and specific studies are needed to explore biomarkers in GI cancers. In this review, we summarize the known biomarkers used in ICI therapy for GI tumors. In addition, some ICI biomarkers applied to other tumors are included to provide insights and further validation for GI tumors. Moreover, we present single-cell analysis and machine learning approaches that have emerged in recent years. Although there are no clear applications yet, it can be expected that these techniques will play an important role in the application of biomarker prediction.

Pulmonary Toxicities of Immunotherapy

Immune checkpoint inhibitors are a form of immunotherapy that are increasingly being used in a wide variety of cancers. Immune-related adverse events (irAEs) pose a major challenge in the treatment of cancer patients. Pneumonitis, the most common lung irAE, can cause significant disruptions in the treatment of cancer and may be life-threatening. The goal of this chapter is to instruct readers on the incidence and clinical manifestations of pneumonitis and to offer guidance in the evaluation and treatment of patients with pneumonitis.

The new insight of treatment in Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a relatively rare malignant tumor originating from the bile duct epithelial cells, and it is one of the malignant tumors with fast growth in incidence and death rate in recent years. CCA carries a very poor prognosis due to a typically late clinical presentation and a poor response to current therapeutics. Currently, surgery is the only possible curative treatment, radiotherapy and chemotherapy also play an important role in slowing down disease progression, while targeted therapy and immunotherapy are changing with each passing day and their combined effect may have great potential for the treatment of CCA; Clinical trials of various treatment options for CCA are also being conducted. This article reviews the different treatment options for CCA and explores the adjuvant treatment for it from a new perspective. In the future, the goal of treatment should be multiple and combined for different CCA patients to achieve individualized programs and improve overall survival.

The importance of establishing genetic phase in clinical medicine

Haplotyping or determination of genetic phase has always played a pivotal role in MHC (HLA studies) both in helping to understand inheritance patterns in diseases such as type 1 diabetes (T1D) and in ensuring better matching in transplantation scenarios such as haematopoietic stem cell transplantation (HSCT), using donors genetically related to the patient. In recent years the need to establish genetic phase in a number of clinical scenarios has become apparent. These include: Genetic phasing for hematopoietic stem cell transplants using unrelated donors, where the HLA haplotypes are not known but where haplotype-matched recipients fare better clinically than allele matched, but haplotype mismatched patients. The use of checkpoint inhibitors is one of the most innovative and exciting developments in cancer treatment in years. An example is the use of the monoclonal ipilimumab to block the CTLA-4 receptor which is known to contain polymorphic sites. Until the phase of these polymorphisms is known it will not be possible to determine how effectively this monoclonal will perform in individual patients. The role of miRNA single strand molecules and their effect on gene expression. Thousands of non-coding genes have been identified and have been shown to be polymorphic, as have their target genes. Genetic phasing of polymorphism both in the miRNA source genes and their targets is clearly a fertile area of research In areas such a drug metabolism where the polymorphic family of CYP genes is responsible for the metabolism of the majority of prescription drugs, determining phase of SNPs is critical to understanding drug metabolism and efficacy. In multigenic disease studies combinations of single nucleotide polymorphisms (SNPs) in participating genes require accurate phasing in order to fully appreciate their role in the disease process. In addition, the level of expression of genes (point 3) is also important in understanding disease processes at the functional level. This review outlines the techniques that are currently available for approximating phase and discusses the clinical relevance of establishing genetic phase in areas of clinical medicine outlined in points 1-3.

The foundations of immune checkpoint blockade and the ipilimumab approval decennial

Cancer immunity, and the potential for cancer immunotherapy, have been topics of scientific discussion and experimentation for over a hundred years. Several successful cancer immunotherapies - such as IL-2 and interferon-α (IFNα) - have appeared over the past 30 years. However, it is only in the past decade that immunotherapy has made a broad impact on patient survival in multiple high-incidence cancer indications. The emergence of immunotherapy as a new pillar of cancer treatment (adding to surgery, radiation, chemotherapy and targeted therapies) is due to the success of immune checkpoint blockade (ICB) drugs, the first of which - ipilimumab - was approved in 2011. ICB drugs block receptors and ligands involved in pathways that attenuate T cell activation - such as cytotoxic T lymphocyte antigen 4 (CTLA4), programmed cell death 1 (PD1) and its ligand, PDL1 - and prevent, or reverse, acquired peripheral tolerance to tumour antigens. In this Review we mark the tenth anniversary of the approval of ipilimumab and discuss the foundational scientific history of ICB, together with the history of the discovery, development and elucidation of the mechanism of action of the first generation of drugs targeting the CTLA4 and PD1 pathways.

Nanobody-based CTLA4 inhibitors for immune checkpoint blockade therapy of canine cancer patients

Cancer is the leading cause of death in the geriatric dog population. Currently, the use of immune checkpoint inhibitors (ICIs) such as anti-CTLA4 antibodies has markedly improved the prognosis of several cancers in their advanced stages. However, ICIs targeting CTLA4 blockade to treat canine cancer patients are yet to define. In this study, we sought to develop, characterize and assess whether chimeric heavy chain only antibodies (cHcAbs) against CTLA4 are viable therapeutic candidates for the treatment of canine cancers. Anti-CTLA4 nanobodies (Nbs) were identified from a yeast nanobody (Nb) library using magnetic-assisted cell sorting (MACS) and flow cytometry. cHcAbs were engineered by genetically fusing the DNA sequences coding for anti-CTLA4 Nbs with the Fc domain of the subclass B of canine IgG. Recombinant cHcAbs were purified from ExpiCHO-S cells. Stable cell lines expressing canine CTLA4 and FcγRI were used to elucidate the binding ability and specificity of cHcAbs. PBMCs isolated from healthy dogs were used to evaluate the ability of cHcAbs to activate canine PBMCs (cPBMCs). Novel Nbs were identified using the extracellular domain of canine CTLA4 protein to screen a fully synthetic yeast nanobody library. Purified Nbs bind specifically to natïve canine CTLA4. We report that chimeric HcAbs, which were engineered by fusing the anti-CTLA4 Nbs and Fc region of subclass B of canine IgG, were half the size of a conventional mAb and formed dimers. The chimeric HcAbs specifically binds both with canine CTLA4 and Fcγ receptors. As the binding of Nbs overlapped with the MYPPPY motif of canine CTLA4, these Nbs were expected to sterically disrupt the interaction of canine CTLA4 to B-7s. Like their human counterpart, canine CTLA4 was expressed on helper T cells and a small subset of cytotoxic T cells. Canine Tregs also constitutively expressed CTLA4, and stimulation with PMA/Ionomycin dramatically increased expression of CTLA4 on the cell surface. Stimulation of cPBMCs in the presence of agonistic anti-CD3 Ab and cHcAb6 significantly increased the expression of IFN-γ as compared to the isotype control. This study identifies a novel nanobody-based CTLA4 inhibitor for the treatment of canine cancer patients.

New insights into exosome mediated tumor-immune escape: Clinical perspectives and therapeutic strategies

Recent advances in extracellular vesicle biology have uncovered a substantial role in maintaining cell homeostasis in health and disease conditions by mediating intercellular communication, thus catching the scientific community's attention worldwide. Extracellular microvesicles, some called exosomes, functionally transfer biomolecules such as proteins and non-coding RNAs from one cell to another, influencing the local environment's biology. Although numerous advancements have been made in treating cancer patients with immune therapy, controlling the disease remains a challenge in the clinic due to tumor-driven interference with the immune response and inability of immune cells to clear cancer cells from the body. The present review article discusses the recent findings and knowledge gaps related to the role of exosomes derived from tumors and the tumor microenvironment cells in tumor escape from immunosurveillance. Further, we highlight examples where exosomal non-coding RNAs influence immune cells' response within the tumor microenvironment and favor tumor growth and progression. Therefore, exosomes can be used as a therapeutic target for the treatment of human cancers.

Cancer immunotherapies revisited: state of the art of conventional treatments and next-generation nanomedicines

Nowadays, the landscape of cancer treatments has broadened thanks to the clinical application of immunotherapeutics. After decades of failures, cancer immunotherapy represents an exciting alternative for those patients suffering from a wide variety of cancers, especially for those skin cancers, such as the early stages of melanoma. However, those cancers affecting internal organs still face a long way to success, because of the poor biodistribution of immunotherapies. Here, nanomedicine appears as a hopeful strategy to modulate the biodistribution aiming at target organ accumulation. In this way, efficacy will be improved, while reducing the side effects at the same time. In this review, we aim to highlight the most promising cancer immunotherapeutic strategies. From monoclonal antibodies and their traditional use as targeted therapies to their current use as immune checkpoint inhibitors; as well as adoptive cell transfer therapies; oncolytic viruses, and therapeutic cancer vaccination. Then, we aim to discuss the important role of nanomedicine to improve the performance of these immunotherapeutic tools to finally review the already marketed nanomedicine-based cancer immunotherapies.

A comparative study of immunotherapy as second-line treatment and beyond in patients with advanced non-small-cell lung carcinoma

Background

Immunotherapy has demonstrated an improved overall survival (OS) and progression-free survival (PFS) as second-line treatment and subsequent lines compared with chemotherapy.

Materials & methods

This was a retrospective review among eight medical centers comprising 100 patients with a confirmed diagnosis of non-small-cell lung carcinoma, in their second-line treatment or beyond with immune checkpoints inhibitors treatment. The current study aimed to analyze effectiveness of immunotherapy in second-line treatment or further in the Mexican population, using PFS rate, OS rate and the best objective response to treatment by RECIST 1.1 as a surrogate of effectiveness.

Results

In total, 100 patients met the criteria for enrollment in the current study. From the total study population, 49 patients (49.0%) were male and 51 (51.0%) were female, with an average age of 60 years and stage IV as the most prevalent clinical stage at the beginning of the study. A total of 61 patients (61.0%) had partial response; 11 (11.0%) stable disease; 2 (2.0%), complete response, 4 (4.0%), progression; and 22 (22.0%) were nonevaluable. We found a median PFS of 4 months (95% CI: 3.2-4.7 months) and an OS of 9 months (95% CI: 7.2-10.7 months).

Conclusion

The response to immunotherapy is similar, with an improvement in OS and PFS, independent of which drug is used. Patients using nivolumab had a better survival, although that was not statistically significant.