CTLA-4 Checkpoint Research Articles

Durvalumab and tremelimumab before surgery in patients with hormone receptor positive, HER2-negative stage II-III breast cancer.

A clinical trial was conducted to assess the feasibility of enrolling patients with Stage II or III hormone receptor positive (HR+)/HER2-negative breast cancer to pre-operative dual PD-L1/CTLA-4 checkpoint inhibition administered prior to neoadjuvant chemotherapy (NACT). Eight eligible patients were treated with upfront durvalumab and tremelimumab for two cycles. Patients then received NACT prior to breast surgery. Seven patients had baseline and interval breast ultrasounds after combination immunotherapy and the responses were mixed: 3/7 patients experienced a ≥30% decrease in tumor volume, 3/7 a ≥30% increase, and 1 patient had stable disease. At the time of breast surgery, 1/8 patients had a pathologic complete response (pCR). The trial was stopped early after 3 of 8 patients experienced immunotherapy-related toxicity or suspected disease progression that prompted discontinuation or a delay in the administration of NACT. Two patients experienced grade 3 immune-related adverse events (1 with colitis, 1 with endocrinopathy). Analysis of the tumor microenvironment after combination immunotherapy did not show a significant change in immune cell subsets from baseline. There was limited benefit for dual checkpoint blockade administered prior to NACT in our study of 8 patients with HR+/HER2-negative breast cancer.

Dual CTLA-4 and PD-1 checkpoint blockade using CS1002 and CS1003 (nofazinlimab) in patients with advanced solid tumors: A first-in-human, dose-escalation, and dose-expansion study.

This study investigated the safety and efficacy of an anti-CTLA-4 monoclonal antibody (CS1002) as monotherapy and in combination with an anti-PD-1 monoclonal antibody (CS1003) in patients with advanced/metastatic solid tumors. The phase 1 study involved phase 1a monotherapy dose-escalation (part 1) and phase 1b combination therapy dose escalation (part 2) and expansion (part 3). Various dosing schedules of CS1002 (0.3, 1, or 3mg/kg every 3 weeks, or 3mg/kg every 9 weeks) were evaluated with 200mg CS1003 every 3 weeks in part 3. Parts 1, 2, and 3 included a total of 13, 18, and 61 patients, respectively. No dose-limiting toxicities or maximum tolerated doses were observed. Treatment-related adverse events (TRAEs) were reported in 30.8%, 83.3%, and 75.0% of patients in parts 1, 2, and 3, respectively. Grade ≥3 TRAEs were experienced by 15.4%, 50.0%, and 18.3% of patients in each part. Of 61 patients evaluable for efficacy, 23 (37.7%) achieved objective responses in multiple tumor types. Higher objective response rates were observed with conventional and high-dose CS1002 regimens (1mg/kg every 3 weeks or 3mg/kg every 9 weeks) compared to low-dose CS1002 (0.3mg/kg every 3 weeks) in microsatellite instability-high/mismatch repair-deficient tumors, melanoma, and hepatocellular carcinoma (50.0% vs. 58.8%, 14.3% vs. 42.9%, and 0% vs. 16.7%). CS1002, as monotherapy, and in combination with CS1003, had a manageable safety profile across a broad dosing range. Promising antitumor activities were observed in patients with immune oncology (IO)-naive and IO-refractory tumors across CS1002 dose levels when combined with CS1003, supporting further evaluation of this treatment combination for solid tumors. CS1002 is a human immunoglobulin (Ig) G1 monoclonal antibody that blocks the interaction of CTLA-4 with its ligands and increases T-cell activation/proliferation. CS1003, now named nofazinlimab, is a humanized, recombinant IgG4 monoclonal antibody that blocks the interaction between human PD-1 and its ligands. In this original article, we determined the safety profile of CS1002 as monotherapy and in combination with CS1003. Furthermore, we explored the antitumor activity of the combination in anti-programmed cell death protein (ligand)-1 (PD-[L]1)-naive microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) pan tumors, and anti-PD-(L)1-refractory melanoma and hepatocellular carcinoma (HCC). CS1002 in combination with CS1003 had manageable safety profile across a broad dosing range and showed promising antitumor activities across CS1002 dose levels when combined with CS1003. This supports further assessment of CS1002 in combination with CS1003 for the treatment of solid tumors.

REXO2 up-regulation is positively correlated with poor prognosis and tumor immune infiltration in hepatocellular carcinoma

BackgroundAs a homologous counterpart to the prokaryotic oligonuclease found in the cellular cytoplasm and mitochondrion, REXO2 assumes a pivotal role in the maintenance of mitochondrial homeostasis. Nevertheless, the precise functions and mechanisms by which REXO2 operates within the context of hepatocellular carcinoma (HCC) have hitherto remained unexamined. MethodsThe expression levels of REXO2 in HCC tissues were evaluated through the utilization of the immunohistochemical (IHC) method, and subsequently, the association between REXO2 expression and the clinicopathological characteristics of HCC patients was scrutinized employing the χ2 test. A battery of experimental assays, encompassing CCK8 viability assessment, cell colony formation, wound healing, and transwell assays, were conducted with the aim of elucidating the biological role of REXO2 within HCC cells. Complementary bioinformatics analyses were undertaken to discern potential correlations between REXO2 and immune infiltration in tumor tissues. ResultsOur IHC findings have unveiled a notable up-regulation of REXO2 within HCC tissues, and this heightened expression bears the status of an independent prognostic factor, portending an adverse outcome for HCC patients (P < 0.05). Upon the attenuation of REXO2 expression, a discernible reduction in the rates of proliferation, invasion and migration of HCC cells ensued (P < 0.05). Furthermore, transcriptome sequencing analysis has provided insights into the putative influence of REXO2 on the development of HCC through the modulation of TNF and NF-κB signaling pathways. Additionally, our bioinformatics analyses have demonstrated a positive correlation between REXO2 and tumor immune cell infiltration, as well as immune checkpoint CTLA-4. ConclusionsIn summation, our results posit an association between the up-regulation of REXO2 and adverse prognostic outcomes, alongside the involvement of immune-related signaling pathways and tumor immune infiltration within the realm of HCC.

T cell senescence: a new perspective on immunotherapy in lung cancer.

T cell senescence is an indication of T cell dysfunction. The ability of senescent T cells to respond to cognate antigens is reduced and they are in the late stage of differentiation and proliferation; therefore, they cannot recognize and eliminate tumor cells in a timely and effective manner, leading to the formation of the suppressive tumor microenvironment. Establishing methods to reverse T cell senescence is particularly important for immunotherapy. Aging exacerbates profound changes in the immune system, leading to increased susceptibility to chronic, infectious, and autoimmune diseases. Patients with malignant lung tumors have impaired immune function with a high risk of recurrence, metastasis, and mortality. Immunotherapy based on PD-1, PD-L1, CTLA-4, and other immune checkpoints is promising for treating lung malignancies. However, T cell senescence can lead to low efficacy or unsuccessful treatment results in some immunotherapies. Efficiently blocking and reversing T cell senescence is a key goal of the enhancement of tumor immunotherapy. This study discusses the characteristics, mechanism, and expression of T cell senescence in malignant lung tumors and the treatment strategies.

Spatial and temporal heterogeneity of tumor immune microenvironment between primary tumor and brain metastases in NSCLC

BackgroundBrain metastasis is a common outcome in non-small cell lung cancer, and despite aggressive treatment, its clinical outcome is still frustrating. In recent years, immunotherapy has been developing rapidly, however, its therapeutic outcomes for primary lung cancer and brain metastases are not the same, suggesting that there may be differences in the immune microenvironment of primary lung cancer and brain metastases, however, we currently know little about these differences.MethodsSeventeen paired samples of NSCLC and their brain metastases and 45 other unpaired brain metastases samples were collected for the current study. Immunohistochemical staining was performed on all samples for the following markers: immune checkpoints CTLA-4, PD-1, PD-L1, B7-H3, B7-H4, IDO1, and EphA2; tumor-infiltrating lymphocytes (TILs) CD3, CD4, CD8, and CD20; tumor-associated microglia/macrophages (TAMs) CD68 and CD163; and tumor proliferation index Ki-67. The differences in expression of these markers were compared in 17 paired samples, and the effect of the expression level of these markers on the prognosis of patients was analyzed in lung adenocarcinoma brain metastases samples. Subsequently, multiplex immunofluorescence staining was performed in a typical lung-brain paired sample based on the aforementioned results. The multiplex immunofluorescence staining results revealed the difference in tumor immune microenvironment between primary NSCLC and brain metastases.ResultsIn 17 paired lesions, the infiltration of CTLA-4+ (P = 0.461), PD-1+ (P = 0.106), CD3+ (P = 0.045), CD4+ (P = 0.037), CD8+ (P = 0.008), and CD20+ (P = 0.029) TILs in brain metastases were significantly decreased compared with primary tumors. No statistically significant difference was observed in the CD68 (P = 0.954) and CD163 (P = 0.654) TAM infiltration between primary NSCLC and paired brain metastases. In all the brain metastases lesions, the expression of PD-L1 is related to the time interval of brain metastases in NSCLC. In addition, the Cox proportional hazards regression models showed high expression of B7-H4 (hazard ratio [HR] = 3.276, 95% confidence interval [CI] 1.335–8.041, P = 0.010) and CD68 TAM infiltration (HR = 3.775, 95% CI 1.419–10.044, P = 0.008) were independent prognosis factors for lung adenocarcinoma brain metastases patients.ConclusionsBoth temporal and spatial heterogeneity is present between the primary tumor and brain metastases of NCSLC. Brain metastases lesions exhibit a more immunosuppressive tumor immune microenvironment. B7-H4 and CD68+ TAMs may have potential therapeutic value for lung adenocarcinoma brain metastases patients.

Abstract A040: Assessing the ability of Fc3TSR to remodel the tumor microenvironment and enhance efficacy of immunotherapies and chemotherapy in a murine model of pancreatic ductal adenocarcinoma

Abstract Introduction: Pancreatic Ductal Adenocarcinoma (PDAC) has a poor survival rate due to late diagnosis where metastasis has often occurred. Angiogenesis, the process by which new vessels form from pre-existing vasculature, is crucial for tumor growth and metastasis. Tumors aggressively upregulate expression of pro-angiogenic factors, stimulating rapid vessel formation. These vessels often lack pericyte coverage and have dysfunctional morphology, leading to high interstitial fluid pressure (IFP). Impaired perfusion and high IFP impede therapy uptake. Fc3TSR is a novel fusion protein derived from the potent angiogenic inhibitor thrombospondin 1, which we have shown to normalize vasculature in ovarian cancer, significantly decreasing tumor size and improving uptake of many therapies. In this study, we evaluated Fc3TSR’s ability to remodel the tumor microenvironment to induce tumor regression and to enhance efficacy of other therapies. Methods: We developed an orthotopic syngeneic murine model of PDAC, whereby we surgically injected 2.5 × 104 murine PDAC cells (KPC) into the tail of the pancreas of C57BL/6 mice. Tumors were allowed to progress for 14 days before intraperitoneal (IP) administration of Fc3TSR (0.158mg/kg) or PBS (control) on day 14 and 21. Gemcitabine (GEM) chemotherapy treated mice received either daily, metronomic dosages of GEM, or weekly, maximum tolerated dosages GEM starting on day 23. Checkpoint inhibitor mice received either PD-L1 (25ug) or CTLA4 (25ug) checkpoint inhibitors on day 23 and 26. Mice were euthanized on day 30 and tumors and the draining lymph nodes were collected and weighed. 1 hour before euthanasia, Fc3TSR and PBS mice were IP injected with Hypoxyprobe (Pimonidazole Hydrochloride) and tumors were immunostained for markers of blood vessels and tumor hypoxia. Results: Fc3TSR induced tumor regression when compared to PBS, but GEM at either dosage did not further enhance this effect. Following Fc3TSR, PD-L1, but not CTLA-4 checkpoint inhibitors significantly reduced tumor size when compared to mice pre-treated with PBS. Fc3TSR treatment also reduced the area of tumor hypoxia. Tumor vasculature is currently being imaged and analyzed for Fc3TSR’s effect on vessel morphology. Conclusion: Our data suggests that normalizing the tumor microenvironment can enhance the uptake and efficacy of combination therapies. Enhanced perfusion could facilitate the migration of activated immune cells and may enhance immune responses in PDAC patients. Here we demonstrate a novel approach to optimize therapeutic efficacy in advanced stage PDAC. Citation Format: Bianca Garlisi, Caroline Aitken, Sylvia Lauks, Julia Stewart, Duncan Petrik, Jack Lawler, Jim Petrik. Assessing the ability of Fc3TSR to remodel the tumor microenvironment and enhance efficacy of immunotherapies and chemotherapy in a murine model of pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr A040.

Abstract C029: Multiple non-redundant immune checkpoints direct therapeutic resistance to chemotherapy and anti-CSF1R in pancreatic ductal adenocarcinoma

Abstract A hallmark of pancreatic ductal adenocarcinoma (PDA) is the formation of a myeloid rich immunosuppressive microenvironment which acts as a barrier to treatment. Therapeutic blockade/depletion of immunosuppressive myeloid cells in combination with chemotherapy or anti-PD-1 checkpoint blockade is under investigation in PDA but has yet to demonstrate broad clinical success. Here, we studied mechanisms of resistance to myeloid-targeted therapy to inform rational combination strategies. Spatial and molecular profiling of the tumor microenvironment in mouse and human PDA revealed vast intra-tumoral myeloid heterogeneity. Depletion of distinct myeloid cell populations triggered T cell infiltration into tumors but also provoked compensatory remodeling of the myeloid compartment. However, concurrent depletion of multiple myeloid subsets using drugs targeting CSF1R, CCR2/5, and CXCR2 was unexpectedly insufficient to overcome treatment resistance and failed to restore productive T cell surveillance in murine models of PDA. Therefore, we next investigated the role of the lymphoid compartment. High-dimensional single cell analyses of T cell infiltrates in PDA revealed an upregulation of multiple checkpoint molecules, including PD-1, LAG3 and CTLA-4, in both mice and humans, suggesting potential resistance mechanisms. In contrast to combinatory myeloid cell depletion, combined blockade of PD-1, LAG3, and CTLA-4 with gemcitabine and anti-CSF1R triggered peripheral CD4+ and CD8+ T cell activation and produced deep and durable tumor responses with a nearly 3-fold increase in median survival and in some cases, tumor cures. Taken together, these studies highlight the contribution of multiple immune checkpoints to cancer immune evasion and reveal a novel role for LAG3 in treatment resistance in PDA. Together, these findings suggest that a multipronged approach to disrupting negative regulatory signals controlling T cell function may be needed to realize the potential of immunotherapy in PDA. Citation Format: Meredith L. Stone, Veronica M. Herrera, Yan Li, Heather Coho, Yuqing Yue, Kathleen Graham, Devora Delman, Shaun O'Brien, Gregory L. Beatty. Multiple non-redundant immune checkpoints direct therapeutic resistance to chemotherapy and anti-CSF1R in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr C029.

Cell-free chromatin particles released from dying cancer cells activate immune checkpoints in human lymphocytes: implications for cancer therapy.

Immune checkpoint blockade is the exciting breakthrough in cancer, but how immune checkpoints are activated is unknown. We have earlier reported that cell-free chromatin particles (cfChPs) that circulate in blood of cancer patients, or those that are released locally from dying cancer cells, are readily internalized by healthy cells with biological consequences. Here we report that treatment of human lymphocytes with cfChPs isolated from sera of cancer patients led to marked activation of the immune checkpoints PD-1, CTLA-4, LAG-3, NKG2A, and TIM-3. This finding was corroborated in vivo in splenocytes of mice when cfChPs were injected intravenously. Significant upregulation of immune checkpoint was also observed when isolated lymphocytes were exposed to conditioned medium containing cfChPs released from hypoxia-induced dying HeLa cells. Immune checkpoint activation could be down-regulated by pre-treating the conditioned media with three different cfChPs deactivating agents. Down-regulation of immune checkpoints by cfChPs deactivating agents may herald a novel form of immunotherapy of cancer.

High CTLA-4 transcriptomic expression correlates with high expression of other checkpoints and with immunotherapy outcome.

CTLA-4 impedes the immune system's antitumor response. There are two Food and Drug Administration-approved anti-CTLA-4 agents - ipilimumab and tremelimumab - both used together with anti-PD-1/PD-L1 agents. To assess the prognostic implications and immunologic correlates of high CTLA-4 in tumors of patients on immunotherapy and those on non-immunotherapy treatments. We evaluated RNA expression levels in a clinical-grade laboratory and clinical correlates of CTLA-4 and other immune checkpoints in 514 tumors, including 489 patients with advanced/metastatic cancers and full outcome annotation. A reference population (735 tumors; 35 histologies) was used to normalize and rank transcript abundance (0-100 percentile) to internal housekeeping gene profiles. The most common tumor types were colorectal (140/514, 27%), pancreatic (55/514, 11%), breast (49/514, 10%), and ovarian cancers (43/514, 8%). Overall, 87 of 514 tumors (16.9%) had high CTLA-4 transcript expression (⩾75th percentile rank). Cancers with the largest proportion of high CTLA-4 transcripts were cervical cancer (80% of patients), small intestine cancer (33.3%), and melanoma (33.3%). High CTLA-4 RNA independently/significantly correlated with high PD-1, PD- L2, and LAG3 RNA levels (and with high PD-L1 in univariate analysis). High CTLA-4 RNA expression was not correlated with survival from the time of metastatic disease [N = 272 patients who never received immune checkpoint inhibitors (ICIs)]. However, in 217 patients treated with ICIs (mostly anti-PD-1/anti-PD- L1), progression-free survival (PFS) and overall survival (OS) were significantly longer among patients with high versus non-high CTLA-4 expression [hazard ratio, 95% confidence interval: 0.6 (0.4-0.9) p = 0.008; and 0.5 (0.3-0.8) p = 0.002, respectively]; results were unchanged when 18 patients who received anti-CTLA-4 were omitted. Patients whose tumors had high CTLA-4 and high PD-L1 did best; those with high PD-L1 but non-high CTLA-4 and/or other expression patterns had poorer outcomes for PFS (p = 0.004) and OS (p = 0.009) after immunotherapy. High CTLA-4, especially when combined with high PD-L1 transcript expression, was a significant positive predictive biomarker for better outcomes (PFS and OS) in patients on immunotherapy.

Roles of RNA m5C modification patterns in prognosis and tumor microenvironment infiltration of diffuse large B-cell lymphoma.

Genetic and epigenetic aberrations display an essential role in the initiation and progression of diffuse large B-cell lymphoma (DLBCL). 5-methylcytosine (m5C), a common RNA modification, regulates various cellular processes and contributes to tumorigenesis and cancer progression. However, m5C alterations in DLBCL remain unclear. Our research constructed an m5C prognostic model utilizing GEO data sets, which can efficiently predict the prognosis of patients with DLBCL, and verified the m5C prognostic model genes by immunohistochemistry analysis. This model was constructed using unsupervised consensus clustering analyses, Least Absolute Shrinkage and Selection Operator (LASSO), and multivariate Cox regression analyses. Based on the expression of m5C genes in the model, patients with DLBCL could be effectively divided into groups with significant survival time differences. The m5C risk-score signature demonstrated a highly significant independent prognostic value. Results from tumor microenvironment analyses revealed that m5C genes altered the infiltration of eosinophils, Tregs, and M2 macrophages. Additionally, they regulated T cell activation by modulating the expression of CTLA4, PDL1, B2M, CD8A, ICOS, and other relevant immune checkpoint expressions. In conclusion, our study presents a robust m5C prognostic model that effectively predicts prognosis in DLBCL. This model may offer a new approach for prognostic stratification and potential therapeutic interventions for patients with DLBCL.

Expression of immune checkpoints PD-L1, CTLA4, LAG3 in the microenvironment of colon adenocarcinoma depending on MMR status

Study of the features of expression of immune checkpoint proteins PD-L1, CTLA4 and LAG3 in the microenvironment of colon adenocarcinoma depending on MMR status. The study group consisted of 32 patients with a morphologically confirmed diagnosis of colon cancer; all of them underwent surgical treatment in the form of hemicolonectomy or resection. The work assessed samples of tumor tissue obtained as a result of surgery, the study was carried out in 3 stages: morphological examination of histological slides of colon tumors at the light-optical level, immunohistochemistry examination of tumor samples to determine the dMMR/pMMR status of carcinoma using a panel of antibodies to proteins of the unpaired nucleotide repair system MLH1, MSH2, MSH6 and PMS2, multiplex analysis of PD-L1, CTLA4, LAG3, CD3+, CD8+, CD163+ markers using the Vectra 3.0.3 tissue scanning system (Perkin Elmer, USA). Significant differences in the expression of PD-L1, CTLA4, LAG3 in the area of the invasive tumor margin were revealed between the dMMR and pMMR groups of colon adenocarcinomas in patients comparable in clinical and morphological characteristics and treatment. In the group of tumors with dMMR status, an increase in the expression of all studied markers was noted. The number of CD3+ TILs was also significantly higher in the invasive margin of tumors with dMMR status. Similarly, in this group of colon carcinomas, a large number of CD163+ macrophages were noted both in the center and in the invasive margin zone. No statistically significant differences were found in the expression of immune checkpoints and the composition of TILs in the central zone of tumors with different MMR status. A study using multiplex immunohistochemical analysis showed that MMR-deficient colon adenocarcinomas are characterized by more pronounced immune infiltration and increased expression of immune checkpoints in microenvironmental cells, mainly in the area of invasive tumor growth. The data obtained may be important for understanding the mechanisms of immune-mediated control of tumor growth and the choice of immunotherapy tactics depending on MMR status.

UBE2C as an Immune-Related Biomarker for Breast Cancer: A Study Based on Multiple Databases

ObjectiveTo screen the target genes that are associated with survival of breast cancer (BRCA) and explore their prognostic values and immune correlations with BRCA using multiple databases.. MethodsThe microarray expression datasets of BRCA were downloaded from the Gene Expresssion Omnibus database (GEO) and analyzed to obtain differentially expressed genes (DEGs). Hub genes were obtained by constructing and visualizing the protein-protein interaction network of DEGs. The key gene was determined using R language, STRING, and Cytoscape, and the differential expression of the key gene was verified using external datasets The Cancer Genome Atlas (TCGA) and quantitative real-time PCR (qRT-PCR) for BRCA tissues of 37 patients. The prognostic value and immunological correlation of UBE2C in BRCA were explored using R language, TIMER, and Gene Set Enrichment Analysis (GSEA). ResultsOf 10 hub genes seleceed from 302 DEGS, UBE2C was identified as the gene associated with BRCA survival. The expression of UBE2C was differentially upregulated in BRCA, as verified by TCGA and qRT-PCR. Prognostic analysis revealed that UBE2C served as an independent prognostic factor. High expression of UBE2C was associated with decreased immune infiltration levels of B cells, CD4+ T cells, CD8+ T cells, macrophages, and myeloid dendritic cells in BRCA tissue. The expression of UBE2C in BRCA showed a significant correlation with immune checkpoints genes PDCD1, CD274, and CTLA4 expressions. There was a positive correlation between the expression of UBE2C and the tumor mutational burden and microsatellite instability. GSEA demonstrated that UBE2C expression significantly enriched 786 immune-related gene sets. ConclusionsUBE2C expression in BRCA tissues is closely related to the BRCA immune microenvironment and showes predictive values on the survivals and prognosis of BRCA patients and the effecacy of immunotherapy. UBE2C may be an potential immune-related prognostic biomarker for BRCA.

CTLA-4 Checkpoint Inhibition Improves Sepsis Survival in Alcohol-Exposed Mice.

Chronic alcohol use increases morbidity and mortality in the setting of sepsis. Both chronic alcohol use and sepsis are characterized by immune dysregulation, including overexpression of T cell coinhibitory molecules. We sought to characterize the role of CTLA-4 during sepsis in the setting of chronic alcohol exposure using a murine model of chronic alcohol ingestion followed by cecal ligation and puncture. Results indicated that CTLA-4 expression is increased on CD4+ T cells isolated from alcohol-drinking septic mice as compared with either alcohol-drinking sham controls or water-drinking septic mice. Moreover, checkpoint inhibition of CTLA-4 improved sepsis survival in alcohol-drinking septic mice, but not water-drinking septic mice. Interrogation of the T cell compartments in these animals following pharmacologic CTLA-4 blockade, as well as following conditional Ctla4 deletion in CD4+ T cells, revealed that CTLA-4 deficiency promoted the activation and proliferation of effector regulatory T cells and the generation of conventional effector memory CD4+ T cells. These data highlight an important role for CTLA-4 in mediating mortality during sepsis in the setting of chronic alcohol exposure and may inform future approaches to develop targeted therapies for this patient population.

A disulfidptosis-related glucose metabolism and immune response prognostic model revealing the immune microenvironment in lung adenocarcinoma.

Lung adenocarcinoma accounts for the majority of lung cancer cases and impact survival rate of patients severely. Immunotherapy is an effective treatment for lung adenocarcinoma but is restricted by many factors including immune checkpoint expression and the inhibitory immune microenvironment. This study aimed to explore the immune microenvironment in lung adenocarcinoma via disulfidptosis. Public datasets of lung adenocarcinoma from the TCGA and GEO was adopted as the training and validation cohort. Based on the differences in the expression of disulfidptosis -related genes, a glucose metabolism and immune response prognostic model was constructed. The prognostic value and clinical relationship of the model were further explored. Immune-related analyses were performed according to CIBERSORT, ssGSEA, TIDE, IPS. We verified that the model could accurately predict the survival expectancy of lung adenocarcinoma patients. Patients with lung adenocarcinoma and a low-risk score had better survival outcomes according to the model. Moreover, the high-risk group tended to have an immunosuppressive effect, as reflected by the immune cell components, phenotypes and functions. We also found that the clinically relevant immune checkpoint CTLA-4 was significantly higher in low-risk group (P<0.05), indicating that the high-risk group may suffer worse tumor immunotherapy efficacy. Finally, we found that this model has accurate predictive value for the efficacy of immune checkpoint blockade in non-small cell lung cancer (P<0.05). The prognostic model demonstrated the feasibility of predicting survival and immunotherapy efficacy via disulfidptosis-related genes and will facilitate the development of personalized anticancer therapy.

Impact of single nucleotide polymorphisms of immune checkpoint CTLA-4 (SNP rs231775 and rs5742909) in susceptibility to Hashimoto's thyroiditis patients

Background: Hashimoto thyroiditis is an autoimmune disorder causing thyroid cell destruction. This research aimed to evaluate CTLA-4 expression levels in patients with Hashimoto's thyroiditis, biochemical parameters. As well as understand the risk and protective effects of two CTLA-4 SNPs polymorphisms (rs231775 and rs5742909) in Iraqi patients. Methods: A case control study was conducted on 50 HT patients (5 men and 45 females) were assembled from Baghdad teaching hospital, Baghdad, Iraq. The relative Gene expression method was used to measure the gene expression of CTLA-4 using qRT-PCR. The single nucleotide polymorphisms of (318C/T (rs231775) and +49A/G (rs5742909) were sequenced for data analysis. Results: There was significant increase of serum CTLA-4 levels, similarity fold change of CTLA-4 was significant upregulated in HT patients compared to controls. The allele and genotypes frequencies according to HWB equilibrium showed significant differences in HT patients 318C/T (rs231775) AA genotypes, while no significant differences in the AG, GG genotypes, respectively compared to controls (p&lt;0.05), There were also no significant differences in the CTLA-4 SNP +49A/G (rs5742909), (CC, CT, TT) genotype, respectively. (p&gt;0.05). Both studied SNPs recoded higher upregulation of soluble and fold change of the immune check point (CTLA-4), respectively. Conclusion: The study reveals that CTLA-4 gene SNPs rs231775 and rs5742909 significantly influence soluble and the expression of CTLA-4 levels in HT patients, potentially causing Hashimoto disease and HT incidence and development.

Design And Evaluating The Efficacy Of Novel Antibodies Enhancing Binding On CTLA-4 And PD-1 Immune Checkpoints

Immune checkpoint proteins, including CTLA-4 and PD-1, have emerged as promising targets for cancer immunotherapy due to their vital role in immune regulation. In this comprehensive study, we conducted a thorough analysis of antibody-protein interactions by employing structural analysis, mutational studies, and antibody-antigen docking simulations. Our findings revealed that antibodies 1 and 2 exhibited strong binding affinities towards CTLA-4 and PD-1 proteins, respectively. Further analysis through alanine scanning identified specific residues, namely Tyr91 on antibody 1, along with Asn31 and Asp96 on antibody 2, as potential mutation sites. Introducing these mutations resulted in the generation of two novel antibodies, 1a, 2a and 2b, which displayed enhanced binding affinity towards their respective target proteins. With their improved binding capabilities, these novel antibodies hold tremendous promise for enhancing the effectiveness of antibody-based therapies designed to target immune checkpoints in cancer treatment. The ultimate objective is to significantly improve the health outcomes of patients by leveraging the potential of these novel antibodies.

Bioinformatic Analysis and Computer-Aided Study to Investigate the Potential Application of a Bioflavonoid Compound Bilobetin in Liver Cancer Treatment.

Hepatocellular carcinoma (HCC/LIHC) is the most common type of primary liver cancer, which is a leading cause of cancer death worldwide. Patients with HCC have a short survival time after diagnosis. Unfortunately, there are no effective treatments for advanced or aggressive HCC. Thus, the rapid development of new therapeutic drugs or treatment methods for HCC is urgently needed. Bioinformatic tools and computer-aided predictions advance the processes of drug development. In this study, we incorporated bioinformatic analyses and computer-aided drug development processes to investigate the potential application of bilobetin, a bioactive compound of bioflavonoid, as a therapeutic agent for HCC treatment. Our results revealed that 4 out of 20 predicted hub target genes of bilobetin displayed functional importance in cancer-related signaling pathways in different cancers, including HCC. Importantly, the mRNA expression levels of these four key hub genes (VEGFA, SRC, MMP9, and CDK1) were significantly different between normal and HCC tumor samples. Their expression levels were significantly associated with the clinical survival outcomes of HCC patients, as well as the immune cell infiltration levels in the HCC tumor microenvironment. In addition, these four genes showed significant co-expression correlated with immune checkpoint genes, including CD274, PDCD1, CTLA4, and CD47. Furthermore, we used computer-aided approaches to investigate the binding affinity and potential binding mechanisms between bilobetin and target proteins encoded by four key hub genes. In conclusion, our study shed light on the potential application of the bioactive bioflavonoid molecule bilobetin in LIHC treatment by regulating four key hub genes.

Immune Checkpoint Inhibitors Current Advances and Future Perspective

Immune therapy has become the fourth method to treat tumors after the traditional methods including radiotherapy, chemotherapy and surgery. Immune therapies use humans’ innate immune system to fight against tumors. Nowadays there are many immune therapies used in clinic, including immune checkpoint inhibitors, cancer vaccines, cytokine therapies, and so on. One of the most mature and widely used immune therapies is immune checkpoint inhibitors (ICIs). Because tumor surface have some proteins that can bind to the receptors on the immune cells, once they are bound the function of the immune system will be inhibited and so tumors can live in human bodies and not be killed by the immune system. Immune checkpoint inhibitor is a method that uses different proteins to block the receptors on the immune cells and the ligands on the tumor cells. In that way, the immune cells will be activated, and kill the tumors. It is worth mentioning that immune checkpoint inhibitors CTLA-4 and PD-1 have made some process in clinical. This article will review some immune checkpoints, make detailed introductions about immune checkpoints CTLA-4, PD-1, and PD-L1 and their recent advances and some immune checkpoints under investigation.

Current Landscape of Immune Checkpoint Inhibitors for Metastatic Urothelial Carcinoma: Is There a Role for Additional T-Cell Blockade?

Urothelial carcinoma (UC) is the most common form of bladder cancer (BC) and is the variant with the most immunogenic response. This makes urothelial carcinoma an ideal candidate for immunotherapy with immune checkpoint inhibitors. Key immune checkpoint proteins PD-1 and CTLA-4 are frequently expressed on T-cells in urothelial carcinoma. The blockade of this immune checkpoint can lead to the reactivation of lymphocytes and augment the anti-tumor immune response. The only immune checkpoint inhibitors that are FDA-approved for metastatic urothelial carcinoma target the programmed death-1 receptor and its ligand (PD-1/PD-L1) axis. However, the overall response rate and progression-free survival rates of these agents are limited in this patient population. Therefore, there is a need to find further immune-bolstering treatment combinations that may positively impact survival for patients with advanced UC. In this review, the current immune checkpoint inhibition treatment landscape is explored with an emphasis on combination therapy in the form of PD-1/PD-L1 with CTLA-4 blockade. The investigation of the current literature on immune checkpoint inhibition found that preclinical data show a decrease in tumor volumes and size when PD-1/PD-L1 is blocked, and similar results were observed with CTLA-4 blockade. However, there are limited investigations evaluating the combination of CTLA-4 and PD-1/PD-L1 blockade. We anticipate this review to provide a foundation for a deeper experimental investigation into combination immune checkpoint inhibition therapy in metastatic urothelial carcinoma.

Pan-cancer analysis of TIM-3 transcriptomic expression reveals high levels in pancreatic cancer and interpatient heterogeneity.

T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), an immune checkpoint receptor, dampens immune function. TIM-3 antagonists have entered the clinic. We analyzed TIM-3 transcriptomic expression in 514 diverse cancers. Transcript abundance was normalized to internal housekeeping genes and ranked (0-100 percentile) to a reference population (735 tumors; 35 histologies [high≥75 percentile rank]). Ninety tumors (17.5%) demonstrated high TIM-3 expression. TIM-3 expression varied between and within tumor types. However, high TIM-3 expression was more common in pancreatic cancer (20/55 tumors, 36.4%; odds ratio, 95% confidence interval (pancreatic vs. other tumors) = 3.176 (1.733-5.818; p < 0.001, multivariate]). High TIM-3 also significantly and independently correlated with high PD-L1 (p = 0.014) and high CTLA-4 (p < 0.001) transcriptomic expression (multivariate). These observations indicate that TIM-3 RNA expression is heterogeneous, but more common in pancreatic cancer and in tumors exploiting PD-L1 and CTLA-4 checkpoints. Clinical trials with patient selection for matched immune-targeted combinations may be warranted.