CTLA-4 Research Articles

CTLA-4 silencing could promote anti-tumor effects in hepatocellular.

Preclinical and clinical research showed that immune checkpoint blockade provides beneficial effects for many patients with liver cancer. This study aimed to assess the effect of CTLA-4-specific siRNA on the proliferation, cell cycle, migration, and apoptosis of HePG2 cells. Transfection of siRNA was performed by electroporation. The viability of cells was determined through MTT assay. Flow cytometry was performed to investigate the cell cycle and apoptosis rate, and the wound-healing assay was used to determine HepG2 cells migration. The expression levels of CTLA-4, c-Myc, Ki-67, BCL-2, BAX, caspase-9 (CAS9), and MMP-2,9,13 were measured by qRT-PCR. Transfection of specific CTLA-4-siRNA significantly inhibited the expression of the CTLA-4 gene. Also, our results revealed that CTLA-4 silencing diminished the proliferation and migration as well as induced the apoptosis of HePG2 cells. CTLA-4-siRNA transfection induced the cell cycle arrest in G2 phase. Moreover, CTLA-4-siRNA transfection reduced the expression levels of c-Myc, Ki-67, BCL-2, MMP-2,9,13, and elevated the expression levels of BAX and caspase-9. Our results suggest that silencing CTLA-4 through specific siRNA may be a promising strategy for future therapeutic interventions for treating liver cancer.

Whole-Exome Sequencing Detecting a Recurrent Pathogenic Mutation, HFE p.His63Asp (H63D) in COVID-19 Patients and Its Effect on Mortality.

In recent years, various coronaviruses have caused severe respiratory illnesses worldwide. For example the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections of COVID-19 outbreak in 2019 in Wuhan, China. Genome-wide association studies (GWAS) have significantly expanded our comprehension of how specific genetic variations are linked to diseases. Research has demonstrated the existence of genetic factors influencing susceptibility to coronaviruses. The objective of this study was to examine the association of certain loci with the COVID-19 in Saudi population. In the present study we have examined the link between the COVID-19 disease and certain genetic variants in hospitalized COVID-19 patients (n = 16) in Tabuk and Bisha, Kingdom Saudi Arabia. We used the genome Analysis Toolkit (GATK) and Comprehensive variant annotation was performed different databases and tools such as Search Tool for the Retrieval of Interacting Genes (STRING), PanelApp and PolyPhen-2. The study showed that the genetic variants associated with genes such as Homeostatic Iron Regulator (HFE) (found in 7 patients, representing 44%), complement factor H (CFH) (6 patients, 38%), cadherin 23 (CDH23) (4 patients, 25%), cytotoxic T-lymphocyte associated protein 4 (CTLA-4) (3 patients, 19%), Transforming Growth Factor Beta 1 (TGFB1) (3 patients, 19%), CREB-binding protein (CREBBP) (2 patients, 13%), E1A Binding Protein P300 (EP300) (2 patients, 13%), hemoglobin subunit beta (HBB) (2 patients, 13%), interferon regulatory factor 7 (IRF7) (2 patients, 13%), and unc-119 lipid binding chaperone (UNC119) (2 patients, 13%) might be associated with susceptibility to coronavirus. We also identified mutations in the COVID-19 patient that are pathogenic or likely pathogenic. A recurrent pathogenic mutation, HFE p.His63Asp (H63D), was identified in 7 patients, suggesting its potential contribution to disease severity. Additionally, a likely pathogenic variant, HBB p.Glu7Val (E7V), was present in 2 patients, highlighting its potential role in disease susceptibility. Our results shed light on the key genetic mechanisms of COVID-19 pathogenesis and help to identify and stratify the individuals or populations that are at risk to corona virus infection. The identification of susceptible individuals or populations assist in prevention and/or in treatment programs.

Establishment of an animal model of immune-related adverse events induced by immune checkpoint inhibitors.

Immunotherapy, specifically immune checkpoint inhibitors (ICIs), has revolutionized cancer treatment. However, it can also cause immune-related adverse events (irAEs). This study aimed to develop a clinically practical animal model of irAEs using BALB/c mice. Subcutaneous tumors of mouse breast cancer 4T1 cells were generated in inbred BALB/c mice. The mice were treated with programmed death-1 (PD-1) and cytotoxic t-lymphocyte antigen 4 (CTLA-4) inhibitors once every 3 days for five consecutive administration cycles. Changes in tumor volume and body weight were recorded. Lung computed tomography (CT) scans were conducted. The liver, lungs, heart, and colon tissues of the mice were stained with hematoxylin-eosin (H&E) staining to observe inflammatory infiltration and were scored. Serum samples were collected, and enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of ferritin, glutamic-pyruvic transaminase (ALT), tumor necrosis factor-α (TNF-α), interferon-gamma (IFN-γ), and interleukin-6 (IL-6). Mouse liver and lung cell suspensions were prepared, and changes in macrophages, T cells, myeloid-derived suppressor cells (MDSCs), and regulatory (Treg) cells were detected by flow cytometry. Mice treated with PD-1 and CTLA-4 inhibitors showed significant reductions in tumor volume and body weight. The tissue inflammatory scores in the experimental group were significantly higher than those in the control group. Lung CT scans of mice in the experimental group showed obvious inflammatory spots. Serum levels of ferritin, IL-6, TNF-α, IFN-γ, and ALT were significantly elevated in the experimental group. Flow cytometry analysis revealed a substantial increase in CD3+T cells, Treg cells, and macrophages in the liver and lung tissues of mice in the experimental group compared with the control group, and the change trend of MDSCs was opposite. The irAE-related animal model was successfully established in BALB/c mice using a combination of PD-1 and CTLA-4 inhibitors through multiple administrations with clinical translational value and practical. This model offers valuable insights into irAE mechanisms for further investigation.

Meta-analysis of CTLA-4 Gene A/G +49 Polymorphism and Susceptibility to Graves' Disease

Meta-analysis of CTLA-4 Gene A/G +49 Polymorphism and Susceptibility to Graves' Disease

Evolving Precision First-Line Systemic Treatment for Patients with Unresectable Non-Small Cell Lung Cancer.

First-line systemic therapy for patients with advanced or metastatic non-small cell lung cancer (NSCLC) has rapidly evolved over the past two decades. First, molecularly targeted therapy for a growing number of gain-of-function molecular targets has been shown to improve progression-free survival (PFS) and overall survival (OS) with favorable toxicity profiles compared to platinum-containing chemotherapy and can be given as first-line systemic therapy in ~25% of patients with NSCLC. Actionable genetic alterations include EGFR, BRAF V600E, and MET exon 14 splicing site-sensitizing mutations, as well as ALK-, ROS1-, RET-, and NTRK-gene fusions. Secondly, inhibitors of programmed cell death protein 1 or its ligand 1 (PD-1/L1) such as pembrolizumab, atezolizumab, or cemiplimab monotherapy have become a standard of care for ~25% of patients with NSCLC whose tumors have high PD-L1 expression (total proportion score (TPS) ≥50%) and no sensitizing EGFR/ALK alterations. Lastly, for the remaining ~50% of patients who are fit and whose tumors have no or low PD-L1 expression (TPS of 0-49%) and no sensitizing EGFR/ALK aberrations, platinum-containing chemotherapy with the addition of a PD-1/L1 inhibitor alone or in combination of a cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitor improves PFS and OS compared to chemotherapy alone. The objectives of this review are to summarize the current data and perspectives on first-line systemic treatment in patients with unresectable NSCLC and propose a practical algorithm for implementing precision biomarker testing at diagnosis.

Brain -cyst-driven genes expression in Toxoplasma Gondii Tehran strain: a parasitic-immunogenicity assessment by dint of RNA-Seq.

Toxoplasma gondii (T. gondii) is an obligate intracellular parasite of warm-blooded vertebrates. At present, High-throughput RNA sequencing analysis have made it possible to determine the role of effective genes in host immune response. The aim of the present study is to global transcriptome analysis of the brain of mice infected with T. gondii Tehran strain for the first time and also to evaluate the expression of effective genes in the chronic form of infection. RNA was extracted from the samples and the library was prepared and sequenced using the IlluminaNovaSeq 6000 system. After analyzing gene expression changes, the results were confirmed by real-time method. We found 125 genes that were significantly differentially expressed between infected and non-infected samples (p < 0.0005). Gene ontology analysis revealed that the expression of many genes is critical for pathways such as T cell receptor signaling pathway, Natural Killer cell mediated cytotoxicity, Lysosome and Apoptosis of the host. As infection with Tehran strain leads to chronic infection in mice, therefore, we investigated the genes effective in creating the chronic form of Toxoplasma infection. The comparative analysis of genes showed increases in the expression of genes ctla4, ccl4, cd3e, c3, lcn2, gbp5, usp18, cyba, tap1 and samhd1 in the in the infected sample, which highlights their role in causing chronic infection. RNA-seq provides a valuable tool for analyzing host transcriptomes, better understanding the parasite-host interaction, and developing future drug and vaccine targets.

The Role of the Immune System in the Course of Hashimoto's Thyroiditis: The Current State of Knowledge.

The process of thyroid autoimmunization develops against the background of genetic predispositions associated with class II human leukocyte antigens (HLA-DR), as well as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), protein tyrosine phosphatase non-receptor type 22 (PTPN22), and forkhead transcription box protein P3 (FOXP3). Environmental factors, such as vitamin D deficiency, Zn, Se, and Mg, as well as infections, chronic stress, pregnancy, smoking, alcohol, medications, intestinal dysbiosis, and malnutrition, also play an important role. The first stage of autoimmunization involves the accumulation of macrophages and dendritic cells, as well as plasma cells. In the second stage, the mutual interactions of individual cells in the immune system lead to a decrease in the level of CD8+ in favor of CD4+, which intensifies the synthesis of T lymphocyte derivatives, especially Th1, Th17, Tfh, and Tc, reducing the level of Treg. Consequently, the number of the anti-inflammatory cytokines IL10 and IL2 decreases, and the synthesis of the pro-inflammatory cytokines IL-2, Il-12, Il-17, IL-21, IL-22, IFN-γ, and TNF-α increases. The latter two especially trigger the pyroptosis process involving the inflammasome. Activation of the inflammasome by IL-β and IL-18 produced by macrophages is one of the mechanisms of pyroptosis in the course of Hashimoto's thyroiditis, involving Gram-negative bacteria and NLRC4. In the next step, the apoptosis of thyroid cells is initiated by the intensification of perforin, granzyme, and proteoglycan synthesis by Tc and NK cells. The current findings raise many possibilities regarding interventions related to the inhibition of pro-inflammatory cytokines and the stimulation of anti-inflammatory cytokines produced by both T and B lymphocytes. Furthermore, since there is currently no effective method for treating thyroid autoimmunity, a summary of the review may provide answers regarding the treatment of not only Hashimoto's thyroiditis, but also other autoimmune diseases associated with autoimmunity.

SPDYC serves as a prognostic biomarker related to lipid metabolism and the immune microenvironment in breast cancer.

Breast cancer remains the most common malignant carcinoma among women globally and is resistant to several therapeutic agents. There is a need for novel targets to improve the prognosis of patients with breast cancer. Bioinformatics analyses were conducted to explore potentially relevant prognostic genes in breast cancer using The Cancer Genome Atlas (TCGA) and The Gene Expression Omnibus (GEO) databases. Gene subtypes were categorized by machine learning algorithms. The machine learning-related breast cancer (MLBC) score was evaluated through principal component analysis (PCA) of clinical patients' pathological statuses and subtypes. Immune cell infiltration was analyzed using the xCell and CIBERSORT algorithms. Kyoto Encyclopedia of Genes and Genomes enrichment analysis elucidated regulatory pathways related to speedy/RINGO cell cycle regulator family member C (SPDYC) in breast cancer. The biological functions and lipid metabolic status of breast cancer cell lines were validated via quantitative real-time polymerase chain reaction (RT‒qPCR) assays, western blotting, CCK-8 assays, PI‒Annexin V fluorescence staining, transwell assays, wound healing assays, and Oil Red O staining. Key differentially expressed genes (DEGs) in breast cancer from the TCGA and GEO databases were screened and utilized to establishthe MLBC score. Moreover, the MLBC score we established was negatively correlated with poor prognosis in breast cancer patients. Furthermore, the impacts of SPDYC on the tumor immune microenvironment and lipid metabolism in breast cancer were revealed and validated. SPDYC is closely related to activated dendritic cells and macrophages and is simultaneously correlated with the immune checkpoints CD47, cytotoxic T lymphocyte antigen-4 (CTLA-4), and poliovirus receptor (PVR). SPDYC strongly correlated with C-C motif chemokine ligand 7 (CCL7), a chemokine that influences breast cancer patient prognosis. A significant relationship was discovered between key genes involved in lipid metabolism and SPDYC, such as ELOVL fatty acid elongase 2 (ELOVL2), malic enzyme 1 (ME1), and squalene epoxidase (SQLE). Potent inhibitors targeting SPDYC in breast cancer were also discovered, including JNK inhibitor VIII, AICAR, and JW-7-52-1. Downregulation of SPDYC expression in vitro decreased proliferation, increased the apoptotic rate, decreased migration, and reduced lipid droplets. SPDYC possibly influences the tumor immune microenvironment and regulates lipid metabolism in breast cancer. Hence, this study identified SPDYC as a pivotal biomarker for developing therapeutic strategies for breast cancer.

A tumor-responsive nanostrategy for reducing the risk of immunotherapy-related myocarditis

Immune checkpoint blockade (ICB) therapy using anti-programmed cell death 1 (PD1) and cytotoxic T lymphocyte antigen 4 (CTLA4), either individual or in combination, has emerged as a pioneer in clinical immunotherapy for various human cancers. However, immune-related adverse effects (irAEs) remain the significant hindrances to their clinical development. In particular, immune-related myocarditis has emerged as a fatal adverse event with the highest fatality rate. For this purpose, we report herein the first example of uncoupling efficacy and myocarditis toxicity in checkpoint blockade cancer therapy. This efficient, yet highly safe access to ICB therapy was achieved by a simple nanoplatform that masked anti-PD1/CTLA4 antibodies to albumin via a ROS-cleavable linker. An in-depth investigation of the experimental autoimmune myocarditis (EAM) mouse model revealed the avoiding exacerbation of myocarditis of our nanomedicine. Notably, the on-demand release of antibodies at the tumor sites enables the combined checkpoint antibody activity. The present study uncouples the ICB efficacy and toxicity, and highlights the irresistible charm of TME-responsive nanoantibodies in clinical cancer immunotherapy, offering solutions to challenges in the advancement of TME-responsive drug delivery toward clinical application.

Expression of Immune Checkpoint Regulator Cytotoxic T Lymphocyte Antigen 4 (CTLA-4) and Programmed Cell Death Protein Ligand 1 (PD-L1) in Invasive Ductal Carcinoma Breast

Expression of Immune Checkpoint Regulator Cytotoxic T Lymphocyte Antigen 4 (CTLA-4) and Programmed Cell Death Protein Ligand 1 (PD-L1) in Invasive Ductal Carcinoma Breast

Molecular characterisation of lupus low disease activity state (LLDAS) and DORIS remission by whole-blood transcriptome-based pathways in a pan-European systemic lupus erythematosus cohort

ObjectivesTo unveil biological milieus underlying low disease activity (LDA) and remission versus active systemic lupus erythematosus (SLE).MethodsWe determined differentially expressed pathways (DEPs) in SLE patients from the PRECISESADS project (NTC02890121)...

Immunotherapy Based on Immune Checkpoint Molecules and Immune Checkpoint Inhibitors in Gastric Cancer-Narrative Review.

Due to its rapid progression to advanced stages and highly metastatic properties, gastric cancer (GC) is one of the most aggressive malignancies and the fourth leading cause of cancer-related deaths worldwide. The metastatic process includes local invasion, metastasis initiation, migration with colonisation at distant sites, and evasion of the immune response. Tumour growth involves the activation of inhibitory signals associated with the immune response, also known as immune checkpoints, including PD-1/PD-L1 (programmed death 1/programmed death ligand 1), CTLA-4 (cytotoxic T cell antigen 4), TIGIT (T cell immunoreceptor with Ig and ITIM domains), and others. Immune checkpoint molecules (ICPMs) are proteins that modulate the innate and adaptive immune responses. While their expression is prominent on immune cells, mainly antigen-presenting cells (APC) and other types of cells, they are also expressed on tumour cells. The engagement of the receptor by the ligand is crucial for inhibiting or stimulating the immune cell, which is an extremely important aspect of cancer immunotherapy. This narrative review explores immunotherapy, focusing on ICPMs and immune checkpoint inhibitors in GC. We also summarise the current clinical trials that are evaluating ICPMs as a target for GC treatment.

Changes in T-cell subsets occur in interstitial lung disease and may contribute to pathology via complicated immune cascade.

The study aimed to investigate the expression profiles of transcription factors, cytokines, and co-stimulatory molecules in helper T (Th)-cell subsets within bronchoalveolar lavage (BAL) samples of patients with interstitial lung diseases (ILDs). Twenty ILDs patients were included in the study, comprising those with idiopathic pulmonary fibrosis (IPF) (n:8), autoimmune-related ILDs (auto-ILD) (n:4), and orphan diseases (O-ILD) (n:8), alongside five control subjects. Flow cytometry was employed to evaluate the Th to cytotoxic Tcell (CTL) ratio in BAL fluid, while cytopathological examination assessed macrophages, lymphocytes, and neutrophils. Quantitative real-time polymerase chain reaction was utilized to investigate the expressions in Th1, Th2, Th17, and regulatory T (Treg) cells. Results revealed elevated Th cell to CTL ratios across all patient groups compared to controls. Furthermore, upregulation of Th1, Th2, Th17, and T-cell factors was observed in all patient groups compared to controls. Interestingly, upregulation of CD28 and downregulation of CTLA-4 and PD-1 gene expression were consistent across all ILDs groups, highlighting potential immune dysregulation. This study provides a comprehensive exploration of molecular immunological mechanisms in ILDs patients, underscoring the dominance of Th2 and Th17 responses and revealing novel findings regarding the dysregulation of CD28, CTLA-4, and PD-1 expressions in ILDs for the first time.

Increased inhibitory surface marker PD-1 expression in CD4+T cells and Th2+T cells in allergen-specific immunotherapy

Recent evidence has shown that T cell exhaustion is implicated in Allergen-specific Immunotherapy (AIT). However, how T cell exhaustion plays a role in AIT is far from clear. Our study aimed to investigate T cell exhaustion associated with allergen exposure during AIT in mice. Ovalbumin (OVA) − sensitized C57BL/6J asthma mouse and AIT mouse models were constructed. Quantitative real-time PCR (qRTPCR) and flow cytometry were used to monitor the occurrence of local and systemic CD4+ T cells and Th2+T cells exhaustion in OVA-sensitized mice. The inhibitory surface marker programmed cell death protein 1 (PD-1) on CD4+ T cells and Th2+T cells was significantly upregulated in AIT mice compared with asthmatic and control mice. The level of PD-1 on the surface of CD4+T cells of asthma mice was significantly higher than that of control mice. The inhibitory surface marker cytotoxic T lymphocyte-associated protein 4 (CTLA-4) on CD4+ T cells and Th2+T cells showed no significant difference between the AIT, asthma and control mice. Collectively, our study indicated that the expression of PD-1 on CD4+ T cells and Th2+T cells was increased in AIT. Allergen exposure promotes the expression of PD-1 on the surface of CD4+ T cells. T cell exhaustion plays an important role in AIT.

ADU-1604, a novel CTLA-4 blocking antibody, to modulate pharmacodynamic markers in patients with PD1 relapse/refractory melanoma.

9552 Background: Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is a negative regulator of T-cell responses, also known as an immune checkpoint. The clinical relevance of CTLA-4 blockade was demonstrated by the approval of ipilimumab for the treatment of melanoma, both in the adjuvant as well as metastatic settings. ADU-1604 is a humanized hIgG1 CTLA-4 antagonist antibody. ADU-1604 binds a unique epitope on CTLA-4 demonstrating, in contrast to ipilimumab full blockade of both CD80 and CD86 interactions. In vitro and in vivo ADU-1604 demonstrates at least as potent efficacy as compared to ipilimumab, was well tolerated in non-human primates and demonstrated enhanced immunogenicity against hepatitis B vaccine in non-human primates. Methods: This is a phase 1, first-in-human (FIH), two-part, open-label clinical trial of intravenous (IV) administration of ADU-1604 given as monotherapy in subjects with advanced-stage, relapsed/refractory melanoma who relapsed or were refractory to a prior anti-PD-1/PD-L1 therapy. Main endpoints are safety of ADU-1604 monotherapy, pharmacokinetics, pharmacodynamics (upregulation of ICOS and Ki-67 on circulation CD4+ T cells and ALC, CD4+ and CD8+ T cells) as well as preliminary clinical efficacy. 20 subjects received escalating doses of ADU-1604 IV (25, 75, 225, 450 mg flat dose) Q3W. In the dose expansion part up to 20 additional patients will be treated with 225 mg dose to confirm recommended Phase 2 dose (RP2D). Safety and preliminary efficacy of ADU-1604 monotherapy in PD1 relapsed/refractory melanoma patients will be evaluated. The study was initiated in June 2022. Results: ADU-1604 was demonstrated to have a typical pharmacokinetic behavior for a human IgG1 antibody and similar exposure was observed as described for ipilimumab. Administration of ADU-1604 in cycle 1 and 2 showed a dose-dependent modulation of ICOS and Ki-67 on circulating CD4+ T cells. Similarly, in cycles 3 and 4 a dose-dependent increase of ALC and CD4+ and CD8+ T cells was detected. Notably, no DLTs across the 25, 75, 225 and 450 mg dose level have occurred. Of the patients treated at 225 and 450 mg dose levels (N=6 at 225 mg and N=6 at 450 mg), two Grade 2 severe adverse events (both immune-related enterocolitis) and two Grade 3 AESIs (ALT elevation and immune-related gastritis) suggesting that ADU-1604 has a relatively mild safety profile. Two patients at 225 mg and one patient at 450 mg demonstrated clinical efficacy. Conclusions: ADU-1604 Phase 1 dose-escalation data indicates clinical activity in line with what has been observed with other CTLA-4 blocking antibodies. Importantly, no DLTs and very limited safety signals were reported during the study. Dose expansion at 225 mg dose is ongoing in subjects with advanced-stage, relapsed/refractory melanoma who relapsed or were refractory to a prior anti-PD-1/PD-L1 therapy. Clinical trial information: 2021-002623-38 .

Targeting Histone 3 Variants Epigenetic Landscape and Inhibitory Immune Checkpoints: An Option for Paediatric Brain Tumours Therapy.

Despite little progress in survival rates with regular therapies, which do not provide complete care for curing pediatric brain tumors (PBTs), there is an urgent need for novel strategies to overcome the toxic effects of conventional therapies to treat PBTs. The co-inhibitory immune checkpoint molecules, e.g., CTLA-4, PD-1/PD-L1, etc., and epigenetic alterations in histone variants, e.g., H3K27me3 that help in immune evasion at tumor microenvironment have not gained much attention in PBTs treatment. However, key epigenetic mechanistic alterations, such as acetylation, methylation, phosphorylation, sumoylation, poly (ADP)-ribosylation, and ubiquitination in histone protein, are greatly acknowledged. The crucial checkpoints in pediatric brain tumors are cytotoxic T lymphocyte antigen-4 (CTLA-4), programmed cell death protein-1 (PD-1) and programmed death-ligand 1 (PDL1), OX-2 membrane glycoprotein (CD200), and indoleamine 2,3-dioxygenase (IDO). This review covers the state of knowledge on the role of multiple co-inhibitory immunological checkpoint proteins and histone epigenetic alterations in different cancers. We further discuss the processes behind these checkpoints, cell signalling, the current scenario of clinical and preclinical research and potential futuristic opportunities for immunotherapies in the treatment of pediatric brain tumors. Conclusively, this article further discusses the possibilities of these interventions to be used for better therapy options.

Unraveling the role of CTLA-4 variants in acute kidney injury after ICI treatments.

e14682 Background: Immune checkpoint inhibitors (ICIs) often result in various immune-related adverse events (irAEs), which limit their therapeutic application and pose challenges to clinical decision-making. Among these irAEs, the incidence rate of ICI-related acute kidney injury (ICI-AKI) is on the rise. Understanding the genetic predisposition to ICI-AKI can inform personalized treatment plans, thereby minimizing risks and optimizing outcomes. This study aims to interrogate risk loci for AKI patients to gain insights into ICI-related AKI in cancer patients and to support the design of more personalized cancer therapies. Methods: This study comprehensively integrates meta-analysis, replication genome-wide association study (GWAS), fine-mapping, and mendelian randomization (MR) to explore potential genetic variants related with ICI-AKI. We first conducted a meta-analysis of 6 ICI pharmacogenomics studies, aggregating effect sizes from these studies using both fixed-effect and random-effects models to address heterogeneity and identified 186 significant genotypes. Subsequently, a GWAS was carried out over the 186 candidate genotypes in an independent cohort from the NIH All of Us program (N = 230,013) using logistic regression, identifying14,773 patients who developed AKI. To identify causal variants, we implemented fine-mapping techniques to further refine our genotype selection. Results: Our study identified genetic variants associated with an increased risk of AKI. Among these, the variant with the strongest association was located at the cytotoxic T lymphocyte antigen 4 (CTLA-4) gene locus, rs3087243 (chr2: 203874196, G&gt;A,T). This genotype exhibited a significant inverse relationship with AKI risk (beta = -8.19e-2, P = 2e-11), suggesting that reduced activity of the CTLA-4 gene may be linked to an elevated risk of developing AKI. Our findings indicate that cancer patients with this genotype may have a lower risk of ICI-related AKI after immunotherapy. In our future study, we will continue investigating significant SNPs including rs3087243 in cancer patients for their ICI-AKI risk. Conclusions: We identified an AKI-tolerant genotype, rs3087243. Patients with this genotype may be safter from developing ICI-related AKI after immunotherapy treatment. This work also highlights the research potential of All of Us clinicogenomics data.

The role of macrophage migration inhibitory factor family and CD74 in the pathogenesis of melanoma.

Melanoma is an aggressive tumour with poor prognosis that arises from the malignant transformation of melanocytes. Over the past few decades, intense research into the pathogenesis of melanoma has led to the development of BRAF and immune checkpoint inhibitors, including antibodies against programmed cell death protein 1 (PD-1) and cytotoxic T lymphocyte-associated protein 4 (CTLA-4), which have shown clinically significant efficacy. However, some tumours do not respond to these therapies initially or become treatment resistant. Most melanoma tissues appear to possess biological characteristics that allow them to evade these treatments, and identifying these characteristics is one of the major challenges facing cancer researchers. One such characteristic that has recently gained attention is the role of macrophage migration inhibitory factor (MIF) and its receptor CD74. This review outlines the cellular and molecular functions of CD74, MIF and their family of proteins. We then review their roles in tumours based on previous reports, highlight their pathological significance in melanoma and discuss their potential as therapeutic targets.

Impact of concurrent antibiotics on survival with immunotherapy in metastatic colorectal and pancreatic cancer.

2609 Background: The interplay between antibiotics and the microbiome has been hypothesized to modify the immune response to cancer and may negatively affect immune checkpoint inhibitor (ICI) efficacy. Methods: We retrospectively reviewed concurrent antibiotics received in the randomized phase II Canadian Cancer Trials Group (CCTG) CO.26 and PA.7 clinical trials. CO.26 evaluated dual programmed death-ligand 1 (PD-L1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibition (with durvalumab and tremelimumab) versus best supportive care only (BSC) in metastatic refractory colorectal cancer (CRC). PA.7 evaluated gemcitabine and nab-paclitaxel +/- durvalumab and tremelimumab in metastatic pancreatic ductal adenocarcinoma. In CO.26, T cell receptor sequencing (TCR-seq) was available at baseline and week 8. Results: In CO.26 (n=180), median (range) age was 65 (36-87) years, 33% (n=59) were female, and 29% (n=50) were ECOG 0. Concurrent exposure to antibiotics was associated with improved overall survival (OS) (7.4 vs 6.2 months, adjusted hazard ratio (aHR) 0.66 (95% confidence interval (CI) 0.46-0.93), p=0.018) in patients with metastatic CRC who received ICIs, but not in patients who received BSC (3.5 vs 4.5 months, HR 1.49 (95% CI 0.81-2.73), p= 0.20); (p-interaction=0.094). In antibiotic class analysis, concurrent exposure of ICIs to fluoroquinolones (9.4 vs 6.2 months, aHR 0.50 (95% CI 0.30-0.82), p=0.0067), but not penicillins or cephalosporins, was associated with improved OS. There was no difference in RAS/RAF status or tumor mutation burden in patients who received antibiotics/fluoroquinolones or not. The results were consistent when also controlling for TMB (antibiotics aHR 0.63 (0.44, 0.91), p=0.013; fluoroquinolones aHR 0.51 (0.31, 0.84), p=0.009). Patients treated with antibiotics did not have a different TCR diversity or clonality between baseline and 8 weeks (p=0.37 and p=0.47) compared to those who did not receive antibiotics (p=0.26 and p=0.60). In PA.7 (n=180), median (range) age was 65 (29-84) years, 48% (n=87) were female, and 24% (n=44) were ECOG 0. Antibiotics were not associated with OS in patients who did/did not receive ICIs (9.7 vs 10.8 months, HR 0.97 (95% CI 0.64, 1.46), p=0.87; 7.4 vs 10.3 months HR 1.22 (95% CI 0.72, 2.09), p=0.46, respectively). Fluoroquinolones were also not associated with OS regardless of whether or not the patient received ICI therapy (10.9 vs 9.8 months, HR 0.74 (95% CI 0.47, 1.15), p=0.18; 7.2 vs 10.2 months, HR 1.18 (95% CI 0.62, 2.27), p=0.62). Conclusions: Concurrent exposure to antibiotics, and specifically fluoroquinolones during ICI therapy was associated with a statistically significant improvement in OS in patients with metastatic CRC, but not metastatic pancreatic cancer. This is discrepant from prior reports in other tumor types and suggests that the gut microbiome may impact ICI efficacy uniquely in patient with CRC. Clinical trial information: NCT02870920 , NCT02879318 .

Retro TIMing: A multicentric retrospective analysis of immunotherapy timing in metastatic melanoma.

9542 Background: Immune checkpoint inhibitors (ICI) targeting programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) are now the standard of care in the treatment of metastatic melanoma (mM). The interplay between cancer cells and tumor microenvironment cells (e.g. immune cells) impacts cancer cell survival, local invasion, and metastatic dissemination. Chrono-immunotherapy is an emerging field as circadian oscillations are observed in the immune landscape (e.g immune cell numbers) as well as in the expression of immunotherapy targets (e.g. PD-1). Recently, a growing body of evidence suggests the outcome can be influenced by the time of the day when immunotherapy is administered (morning versus in the afternoon). This work aims to evaluate the impact of immunotherapy with ICIs administration timing on the overall survival (OS) and progression-free survival (PFS) of patients with mM. Methods: Multicentric, retrospective cohort study of mM patients under immunotherapy (ipilimumab/nivolumab, nivolumab, or pembrolizumab) with PS 0-1, between July 2016 and June 2023. Clinical, demographic characteristics, and time of treatment administration were obtained from medical records. Patients were distributed in two groups: those who received less than 75% of infusions after 2pm (morning group), and those who received at least 75% of infusions after 2pm (afternoon group). OS and PFS were calculated with Kaplan-Meier method and tested using a Cox regression model, with a 95% confidence interval. Results: We identified 168 patients from the 7 Oncology Centers included. The majority were men (n=100, 59.5%), with a median age of 69 years old, and 22% of the patients (n=37) were included in the afternoon group. No significant demographic or tumor burden differences were found between the morning and afternoon groups. The median follow-up time was 29 months, the estimated median PFS was 11.8 months (CI 95%, 8.0 - 14.6) and median OS was 31.4 months (CI 95%, 20.6 - NR). Patients in the afternoon group presented with shorter OS compared with those in the morning group (14.4 vs 37.6 months; HR 1.94 [CI 95% 1.16 to 3.23]; p 0,014). No statistically significant differences were observed in PFS. Subgroup analysis showed an increased detriment of performing ICIs infusions in the afternoon in women (OS 8.7 (4.2, 21.2) versus 30.9 months (18.9, NR), p=0.002; afternoon versus morning) and those older than 65 years old (OS 14.2 months (4.7, 31.4) versus 24.2 months (18.3, NR), p=0.002); afternoon versus morning). Conclusions: This work provides valuable insights into the potential role of the circadian timing of immunotherapy treatments for mM, suggesting patients may benefit from having ICIs infusion in the morning. Prospective randomized studies with a translational approach are needed to validate and fully understand the underlying mechanisms at play in circadian timing efficacy.