T-cell Immunoglobulin And Mucin-domain Containing-3 Research Articles

Immune checkpoint inhibitors as potential therapy for reverting T-cell exhaustion and reverting HIV latency in people living with HIV.

The immune system of people living with HIV (PLWH) is persistently exposed to antigens leading to systemic inflammation despite combination antiretroviral treatment (cART). This inflammatory milieu promotes T-cell activation and exhaustion. Furthermore, it produces diminished effector functions including loss of cytokine production, cytotoxicity, and proliferation, leading to disease progression. Exhausted T cells show overexpression of immune checkpoint molecules (ICs) on the cell surface, including programmed cell death protein 1 (PD-1), cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), T-cell immunoglobulin and mucin-domain containing-3 (TIM-3), T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT), and lymphocyte activation gene-3 (LAG-3). The ICs also play a crucial role in T-cell exhaustion by reducing the immune response to cancer antigens. Immunotherapy based on immune checkpoint inhibitors (ICIs) has changed the management of a diversity of cancers. Additionally, the interest in exploring this approach in the setting of HIV infection has increased, including AIDS-defining cancers and non-AIDS-defining cancers in PLWH. To date, research on this topic suggests that ICI-based therapies in PLWH could be a safe and effective approach. In this review, we provide an overview of the current literature on the potential role of ICI-based immunotherapy not only in cancer remission in PLWH but also as a therapeutic intervention to restore immune response against HIV, revert HIV latency, and attain a functional cure for HIV infection.

CD33-TIM3 Dual CAR T Cells: Enhancing Specificity While Maintaining Efficacy Against AML

Background: The myeloid associated antigen CD33 is overexpressed in over 88% of Acute myeloid leukemia (AML) patients, making it a suitable target antigen for CAR T cell therapy across different genetic subtypes. Despite the development of clinical trial data, there remains a concern about on-target off-leukemia toxicity. To enhance specificity, we generated dual targeting CAR T cells that target CD33 and/or T-cell immunoglobulin and mucin-domain containing-3 (TIM3). The latter is known to be expressed on LSCs, but not on healthy hematopoietic precursor or stem cells. Notably, TIM3 is recognized for its inhibitory immunomodulatory role further enhancing the suitability of this target antigen. The objective of this research was to explore various CD33 and TIM3 dual-targeting CAR T cells approaches that enhance AML specificity and maintain high anti-AML activity. Methods: The hybridoma technology was used to generate antibodies against TIM3 immunized mice. Antibodies were screened for TIM3 specificity via ELISA and FACS. The anti-TIM3 single-chain variable fragment (scFv) DNA sequence was sequenced from hybridoma cells. Furthermore, the binding ability to TIM3 antigen (PDB ID: 5F71) was evaluated using AlphaFold. The CD33 scFv was derived from Gemtuzumab ozogamicin (clone: hP67.6). ScFv sequences and co-stimulation domains (CD28 or 4-1BB) were cloned into a pMP71 vector. Retrovirus for transduction was produced using the 293Vec-GALV and RD114 retroviral production system. In vitro co-culture assays of CAR T cells and target cells were performed to study the efficacy of CAR T cells. The cytotoxicity against wild-type and TIM3 transduced AML cell lines (THP-1 and OCI-AML3) was assessed by multiparameter flow cytometry (MPFC). The secretion of effector cytokines (IFN-γ, TNF, IL-2) was analyzed via CBA assays. In addition, avidity between CAR T cells and target cells was determined by Z-Movie analyzer. The different CAR constructs were screened for on-target off-tumor toxicity in colony forming unit assays (CFU) using isolated CD34 + hematopoietic stem and progenitor cells (HSPCs) from healthy doners after 14 days. In order to compare CAR constructs regarding long-term efficacy in antigen restimulation assays, CAR T cells were co-cultured with irradiated TIM3 transduced OCI-AML3 every 4 days at an E: T ratio of 1:1 for 24 days. Moreover, CAR T-cell proliferation, checkpoint marker expression and T-cell subset differentiation were analyzed via MPFC. Results: All dual CAR T cells (compound, split, tandem, pooled) were generated with high and robust transduction efficacy (Figure 1A). TIM3-dependent fratricide was not observed during CAR T cell manufacturing. Compared to single antigen targeting CAR T cells, dual CAR T cells showed enhanced cytotoxicity against AML cell lines and primary AML cells (Figure 1B). Moreover, we also observed a strong increase in the secretion of proinflammatory cytokines (IFN-γ and IL-2) and higher avidity of dual CAR T cells. Notably, split CAR T cells demonstrated greater specificity in cocultures directed against mono vs. dual-target antigen expression cell lines. In accordance with these observations, split CAR T cells did not exert on-target off-leukemia toxicity against healthy HSC in CFU assays. In the antigen restimulation assay, we observed that compound CAR T cells exhibited diminished expanding capacity and heightened expression of exhaustion markers in comparison to the other CAR T constructs. Conclusion: We developed multiple CD33 and TIM3 dual CAR T cells using both “AND” and “OR” gating strategies in this study. Our findings revealed that dual CAR T cells provided higher avidity and cytotoxicity compared to single targeting CAR T cells against dual antigen expressing target cells in vitro. Importantly, only the split CAR T constructs demonstrated specific killing of CD33 +TIM3 + cell lines and primary AML cells while sparing HSPCs. Prospectively, compound, tandem, pooled CD33 TIM3 specific CAR T cells might be helpful in a bridge to transplant setting, whereas split CAR T cells might provide a higher safety profile, thereby allowing a transplant independent approach. To advance our concepts, we are currently conducting in vivo experiments in an NSG mouse model.

Expression of B7-H3 and TIM-3 in gastric-type endocervical adenocarcinoma: prevalence, association with PD-L1 expression, and prognostic significance.

Gastric-type endocervical adenocarcinoma (GEA) is the second most common subtype of endocervical adenocarcinoma and has a poor prognosis. Anti-programmed death-1 and anti-programmed death-ligand 1 (PD-L1) inhibitors have emerged as a major treatment option for GEA; however, data on the expression of other immune checkpoints in GEA are limited. We analyzed the expression of T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) and B7 homolog 3 protein (B7-H3) in 58 GEA and investigated their prognostic significance as well as association with PD-L1 expression and other known prognostic factors. Applying the tumor proportion score (TPS) with a cutoff of 1%, B7-H3 and TIM-3 were present in 48.3% and 17.2% of cases, respectively. Applying the combined positive score (CPS) with a cutoff of 1, TIM-3 expression was present in 70.7% of cases. Moreover, the expression of three checkpoints (B7-H3, TIM-3, and PD-L1) was incompletely overlapping. Patients with B7-H3 positive tumors (by TPS) or TIM-3 positive tumors (by TPS) had significantly worse recurrence-free survival (RFS) and overall survival (OS) (log-rank). Using CPS, patients with TIM-3 positive tumors showed significantly worse RFS (log-rank). Similarly, B7-H3 positivity (by TPS) and TIM-3 positivity (by TPS) were associated with worse RFS and OS in univariate analysis. TIM-3 positivity (by CPS) was associated with worse RFS in univariate analysis and the final Cox multivariate analysis. In conclusion, our results show that (1) B7-H3 and TIM-3 are frequently expressed in GEA and their expression overlaps incompletely with PD-L1; and (2) both B7-H3 and TIM-3 are independent negative prognostic markers in GEA.

T-cell immunoglobulin and mucin-domain containing-3 (TIM-3): Solving a key puzzle in autoimmune diseases.

Dysfunctional immune cells participate in the pathogenesis of a variety of autoimmune diseases, although the specific mechanisms remain elusive and effective clinical interventions are lacking. Recent research on immune checkpoint molecules has revealed significant expression of T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) on the surfaces of various immune cells. These include different subsets of T cells, macrophages, dendritic cells, natural killer cells, and mast cells. Further investigation into its protein structure, ligands, and intracellular signaling pathway activation mechanisms has found that TIM-3, by binding with different ligands, is involved in the regulation of crucial biological processes such as proliferation, apoptosis, phenotypic transformation, effector protein synthesis, and cellular interactions of various immune cells. The TIM-3-ligand axis plays a pivotal role in the pathogenesis of numerous conditions, including autoimmune diseases, infections, cancers, transplant rejection, and chronic inflammation. This article primarily focuses on the research findings of TIM-3 in the field of autoimmune diseases, with a special emphasis on the structure and signaling pathways of TIM-3, its types of ligands, and the potential mechanisms implicated in systemic lupus erythematosus, multiple sclerosis, rheumatoid arthritis, as well as other autoimmune diseases and chronic inflammation. The latest research results in the field of immunology suggest that TIM-3 dysfunction affects various immune cells and participates in the pathogenesis of diseases. Monitoring the activity of its receptor-ligand axis can serve as a novel biological marker for disease clinical diagnosis and prognosis evaluation. More importantly, the TIM-3-ligand axis and the downstream signaling pathway molecules may become key targets for targeted intervention treatment of autoimmune-related diseases.

Clinicopathological and prognostic significance of PD-L1 and TIM-3 expression in medullary thyroid carcinoma: a retrospective immunohistochemistry study

PurposeExpression of the programmed death-ligand 1 (PD-L1) and T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) in medullary thyroid carcinoma (MTC) has been controversial and rarely reported.MethodsSurgical specimens of 190 MTC patients who had initial curative-intent surgery were collected. Immunohistochemistry of PD-L1 and TIM-3 was performed using 22C3 pharmDx (Dako, Carpinteria, CA) and anti-TIM-3 (1:500, ab241332, Abcam). Stained slides were scored using a combined positive score (CPS) with a cutoff of ≥ 1. We established correlations between PD-L1 expression, TIM-3 expression, clinicopathological, and survival data.Results13 cases (13/190, 6.84%) were positive for PD-L1 expression, and 42 cases (42/154, 27.27%) for TIM-3 expression. PD-L1 expression was correlated to TIM-3 expression (P = 0.002), but was not related to overall survival (OS) or progression-free survival (PFS). TIM-3 expression was correlated to perineural invasion (P = 0.040). Multivariate Cox analysis showed that lymphovascular invasion (LVI) was independently associated with OS. And tumor size, LVI, and lymph node metastases were significantly associated with PFS. Furthermore, the multivariate logistic analysis showed multifocal status, LVI, pathological T stage and lymph node metastasis were independent risk factors for biochemical recurrence/persistent disease.ConclusionsWe demonstrated that PD-L1 and TIM-3 expression were not frequent in MTC and were not associated with survival prognosis. Our results should be considered when clinical trials of PD-L1 or TIM-3 blockades are implemented.

TIM-3/Galectin-9 and CD160 expression in salivary adenoid cystic carcinoma.

Investigating T-cell immunoglobulin and mucin-domain containing-3 (TIM-3), Galectin 9 (Gal-9), CD160 expression and tumor-infiltrating lymphocytes (TILs) and correlation with clinicopathological characteristics of salivary adenoid cystic carcinoma (SACC). Sixty cases of SACC were detected by immunohistochemical staining to evaluate TIM-3, Gal-9, and CD160 expression and analyze the correlation between TIM-3, Gal-9, CD160 expression and clinicopathologic features by rank-sum test. The association of TILs with TIM-3, Gal-9, and CD160 expression in SACC stromal was done by Chi-square test. TIM-3 and CD160 overexpression were correlated with recurrence of SACC (p = 0.029, p = 0.007, respectively). High Gal-9 expression was correlated with pathological classification (p = 0.018). The average percentage of TILs was 18.2% in SACC and most of TILs were more likely to occur in minor salivary glands (p = 0.038). Pairwise positive correlations were observed between the expression of TIM-3, Gal-9, and CD160 in tumor cells as well as in TILs, respectively. Low density of TILs was characteristic of the SACC microenvironment, with upregulation of TIM-3, Gal-9, and CD160 all occurring. However, TIM-3, Gal-9, and CD160 expression in the stromal dependent on the number of TILs represent potential therapeutic targets in SACC.

Biomarker Profiles and Immunologic Predictors of Neurodevelopment in Children who are HIV Exposed Uninfected

Background: Children who are HIV-exposed uninfected (HEU) have higher morbidity and mortality rates than their unexposed uninfected counterparts (HU). HEU also exhibit lower neurodevelopmental outcomes. Previous studies show that HIV-induced immune dysregulation can be linked to decreased neurodevelopment in HIV+ children. However, the role of inflammation on neurodevelopment in HEU remains unclear. 
 Methods: This study investigated the plasma levels of 81 biomarkers in 82 Kenyan children between the ages of 18 and 36 months. Neurodevelopment was measured using the Bayley Scales of Infant and Toddler Development, 3rd edition. Bayesian model averaging was used to identify significant biomarkers. 
 Results: HEU showed lower levels of 12 different proinflammatorycytokines/chemokines/growth factors: IL-12, leukemia inhibitory factor (LIF), macrophage migration inhibitory factor (MIF), TNF-related weak inducer of apoptosis (TWEAK), and A proliferation inducing ligand (APRIL); BLC, eoxtaxin-2, I-TAC, monokine induced by gamma interferon (MIG), and MIP-3a; fibroblast growth factor-2 (FGF-2) and granulocyte colony-stimulating factor (G-CSF). HEU showed higher levels of 2 inhibitory soluble immune checkpoints: T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) and CD40. Bayesian model averaging identified the biomarkers to best predict HEU vs. HU status were IL-12, IL-13, and CD40. In HU children, hepatocyte growth factor (HGF) and IL-5 predicted cognitive scores, BLC and IL-7 predicted motor outcomes, and IL-1a, IL-2R, IL-5, and maternal education predicted language scores. In HEU, FGF-2 predicted language scores, and IL-22 predicted motor development. Statistical analysis identified IL-2R and IL-22 as the strongest predictors of neurodevelopmental outcomes in HU and HEU, respectively.
 Conclusion/Potential Impact: This study shows that HEU exhibit an immune suppressive biomarker profile, rather than an inflammatory profile as indicated in previous studies. The significant biomarkers we found may be used to determine children at risk of decreased poor neurodevelopmental outcomes, allowing more time for intervention.

The Variations' in Genes Encoding TIM-3 and Its Ligand, Galectin-9, Influence on ccRCC Risk and Prognosis.

Renal cell cancer is the most common type of kidney cancer in adults, and clear cell renal cell carcinoma (ccRCC) is the most diagnosed type. T cell immunoglobulin and mucin-domain-containing-3 (TIM-3) belongs to immunological checkpoints that are key regulators of the immune response. One of the known TIM-3 ligands is galectin-9 (LGALS9). A limited number of studies have shown an association between TIM-3 polymorphisms and cancer risk in the Asian population; however, there is no study on the role of LGALS9 polymorphisms in cancer. The present study aimed to analyze the influence of TIM-3 and LGALS9 polymorphisms on susceptibility to ccRCC and patient overall survival (OS), with over ten years of observations. Using TaqMan probes, ARMS-PCR, and RFPL-PCR, we genotyped two TIM-3 single-nucleotide polymorphisms (SNPs): rs1036199 and rs10057302, and four LGALS9 SNPs: rs361497, rs3751093, rs4239242, and rs4794976. We found that the presence of the rs10057302 A allele (AC + AA genotypes) as well as the rs4794976 T allele (GT + TT genotypes) decreased susceptibility to ccRCC by two-fold compared to corresponding homozygotes. A subgroup analysis showed the association of some SNPs with clinical features. Moreover, TIM-3 rs1036199 significantly influenced OS. Our results indicate that variations within TIM-3 and LGALS9 genes are associated with ccRCC risk and OS.

Abstract 6150: Potential role of CD47 in T cell exhaustion program

Abstract Multiple suppressive mechanisms within the tumor microenvironment (TME) are capable of blunting anti-tumor T cell responses. These include engagement of inhibitory receptors expressed in tumor-associated, exhausted CD8 T cells, such as programmed cell death protein 1 (PD-1), T-cell immunoglobulin and mucin-domain containing-3 (TIM-3), lymphocyte-activation gene 3 (LAG-3), 2B4 (also known as CD244), and T cell immunoreceptor with Ig and ITIM domains (TIGIT). While immune checkpoint blockade therapies aimed at reversing the dysfunctional state of tumor-associated T cells have demonstrated clinical effectiveness, not all cancer patients achieve long-term disease control. This is due, at least in part, to the refractory nature of what are categorized as terminally exhausted CD8 T cells to be reinvigorated by, for example, PD-1/PD-L1 blockade. As CD8 T cell exhaustion (or dysfunction) is a major therapeutic challenge, gaps in our understanding of cellular and molecular mechanisms underlying the T cell exhaustion (or dysfunction) program in cancer warrant further study of pathways that program T cells toward exhaustion (or dysfunction). Through comprehensive immune profiling of tumor-infiltrating T lymphocytes (TILs), we found that CD47 expression in CD8 TILs isolated from melanoma patients significantly correlates with expression of several checkpoint inhibitory molecules (e.g., TIM-3, PD-1 and LAG-3). Additionally, our re-analysis of single cell data from melanoma patients revealed that terminally exhausted T cells (Tex) and TCF7hi Tex precursor cells exhibit high levels of CD47 transcripts, suggesting phenotypic association of CD47 with T cell exhaustion. We confirmed our observations in murine B16-F10 melanoma where CD47 expression is significantly upregulated in exhausted CD8 TILs. We also show that CD47 functions as a negative regulator for T cell proliferation and function during T cell priming. To address the role of CD47 during the development of CD8 T cell exhaustion/dysfunction in cancer, we performed adoptive T cell transfer of the naïve-sorted Cd47+/+ (WT) and Cd47+/- (Het) antigen specific Pmel-1 CD8 T cells (but not Cd47-deficient Pmel-1 CD8 T cells as they would be subject to innate immune clearance) into B16 tumor-bearing mice and found that Cd47-Het Pmel-1 CD8 TILs, as compared to the Cd47-WT Pmel-1 CD8 TILs, exhibit less expression of exhaustion-related genes (e.g. Pdcd1, Lag3 and Tox), and increased expression of genes associated with T cell activation and proliferation (e.g. Mki67, Lck, Cd69, Gzma, Gzmk). We further confirmed that thrombospondin-1 (TSP-1), as an extracellular matrix protein and a ligand of CD47, contributes to driving the differentiation of CD8 T cells toward exhaustion. Our data highlight for the first time the potential of extracellular matrix protein TSP-1 in programming CD8 T cell exhaustion in cancer through its interaction with CD47 expressed on CD8 T cells. Citation Format: Chien-Huan Weng, Fadi Samaan, Sadna Budhu, Levi Mangarin, Sébastien Monette, Cailian Liu, Stephane Pourpe, Linda Hamadene, Hong Zhong, Xia Yang, David Schroder, Roberta Zappasodi, Pamela Holland, Jedd D. Wolchok, Taha Merghoub. Potential role of CD47 in T cell exhaustion program [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6150.

Increased coexpression of PD-L1 and TIM3/TIGIT is associated with poor overall survival of patients with esophageal squamous cell carcinoma

BackgroundImmune checkpoint (IC) blockades (ICBs) significantly improve patients’ clinical outcomes with solid tumors. Because the objective response rate of single-agent ICB is limited, it is meaningful to explore the combination...

TIM-3 in normal and malignant hematopoiesis: Structure, function, and signaling pathways.

Acute myeloid leukemia (AML) is hierarchically organized by self‐renewing leukemic stem cells (LSCs). LSCs originate from hematopoietic stem cells (HSCs) by acquiring multistep leukemogenic events. To specifically eradicate LSCs, while keeping normal HSCs intact, the discrimination of LSCs from HSCs is important. We have identified T‐cell immunoglobulin and mucin‐domain containing‐3 (TIM‐3) as an LSC‐specific surface molecule in human myeloid malignancies and demonstrated its essential function in maintaining the self‐renewal ability of LSCs. TIM‐3 has been intensively investigated as a “coinhibitory” or “immune checkpoint” molecule of T cells. However, little is known about its distinct function in T cells and myeloid malignancies. In this review, we discuss the structure of TIM‐3 and its function in normal blood cells and LSCs, emphasizing the specific signaling pathways involved, as well as the therapeutic applications of TIM‐3 molecules in human myeloid malignancies.

Immune checkpoint inhibitors in lymphoma: challenges and opportunities.

Immune checkpoint inhibitors (ICIs) are immunomodulatory antibodies that intensify the host immune response, thereby leading to cytotoxicity. The primary targets for checkpoint inhibition have included cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), programmed cell death receptor-1 (PD-1) or programmed cell death ligand-1 (PD-L1). ICIs have resulted in a change in treatment landscape of various neoplasms. Among hematologic malignancies, ICIs have been most successful in certain subtypes of lymphomas such as classic Hodgkin lymphoma (cHL) and primary mediastinal B-cell lymphoma (PMBCL). However, there have been several challenges in harnessing the host immune system through ICI use in other lymphomas. The underlying reasons for the low efficacy of ICI monotherapy in most lymphomas may include defects in antigen presentation, non-inflamed tumor microenvironment (TME), immunosuppressive metabolites, genetic factors, and an overall lack of predictive biomarkers of response. In this review, we outline the existing and ongoing studies utilizing ICI therapy in various lymphomas. We also describe the challenges leading to the lack of efficacy with ICI use and discuss potential strategies to overcome those challenges including: chimeric antigen receptor T-cell therapy (CAR-T therapy), bispecific T-cell therapy (BiTE), lymphocyte activation gene-3 (LAG-3) inhibitors, T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) inhibitors, vaccines, promotion of inflammatory macrophages, indoleamine 2,3-dioxygenase 1 (IDO1) inhibitors, DNA methyltransferase inhibitors (DNMTi) and histone deacetylase inhibitors (HDACi). Tumor mutational burden and interferon-gamma release assays are potential biomarkers of ICI treatment response beyond PD-L1 expression. Further collaborations between clinicians and scientists are vital to understand the immunopathology in ICI therapy in order to improve clinical outcomes.

Mesoporous silica nanoparticles inflame tumors to overcome anti-PD-1 resistance through TLR4-NFκB axis

BackgroundThe clinical benefits of antiprogrammed cell death protein 1 (PD-1) therapy are compromised by resistance in immunologically cold tumors. Convergence of immunotherapy and bioengineering is potential to overcome the resistance....

Skin dendritic cells in melanoma are key for successful checkpoint blockade therapy

BackgroundImmunotherapy with checkpoint inhibitors has shown impressive results in patients with melanoma, but still many do not benefit from this line of treatment. A lack of tumor-infiltrating T cells is...

LAG-3, TIM-3 and VISTA Expression on Tumor-Infiltrating Lymphocytes in Oropharyngeal Squamous Cell Carcinoma-Potential Biomarkers for Targeted Therapy Concepts.

Tumor growth and survival requires a particularly effective immunosuppressant tumor microenvironment (TME) to escape destruction by the immune system. While immunosuppressive checkpoint markers like programmed cell death 1 ligand (PD-L1) are already being targeted in clinical practice, lymphocyte-activation-protein 3 (LAG-3), T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) and V-domain Ig suppressor of T cell activation (VISTA) inhibitors are currently under investigation in clinical trials. Reliable findings on the expression status of those immune checkpoint inhibitors on tumor-infiltrating lymphocytes (TILs) in the TME of oropharyngeal squamous cell carcinoma (OPSCC) are lacking. This work aims to describe the expression of LAG-3, TIM-3, and VISTA expression in the TME of OPSCC. We created a tissue microarray of paraffin-embedded tumor tissue of 241 OPSCC. Expression of the immune checkpoint protein LAG-3, TIM-3, and VISTA in OPSCC was evaluated using immunohistochemistry and results were correlated with CD8+ T-cell inflammation and human papillomavirus (HPV)-status. 73 OPSCC stained positive for LAG-3 (31%; HPV+:44%; HPV-:26%, p = 0.006), 122 OPSCC stained positive for TIM-3 (51%; HPV+:70%; HPV-:44%, p < 0.001) and 168 OPSCC (70%; HPV+:75%; HPV-:68%, p = 0.313) for VISTA. CD8+ T-cells were significantly associated with LAG-3, TIM-3 and VISTA expression (p < 0.001, p < 0.001, p = 0.007). Immune checkpoint therapy targeting LAG-3, TIM-3, and/or VISTA could be a promising treatment strategy especially in HPV-related OPSCC. Future clinical trials investigating the efficacy of a checkpoint blockade in consideration of LAG-3, TIM-3, and VISTA expression are required.

Concurrent Chemoradiotherapy Increases the Levels of Soluble Immune Checkpoint Proteins in Patients with Locally Advanced Cervical Cancer

Concurrent chemoradiotherapy (CCRT) could influence systematic immunity in cancer patients, but its impact on soluble immune checkpoint molecules remain largely unknown. Here, we investigated the dynamic alterations of 16 soluble immune checkpoint molecules in locally advanced cervical cancer (LACC) patients treated with CCRT. Sixty LACC patients treated with CCRT were prospectively enrolled and patients’ blood was collected before, during, and at the end of CCRT. Sixteen soluble immune checkpoint molecules were tested by Luminex platform. Tumor response was evaluated based on RECIST 1.1 guidelines at one month after CCRT. One-way analysis of variance with Bonferroni's post-test or paired t tests were used to evaluate the change of the levels of soluble immune checkpoint molecules. Forty-five (75%) patients experienced complete response (CR), 12 (20%) patients experienced partial response (PR), and 3 (5%) patients experienced stable disease after CCRT. Levels of T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) increased both during and at the end of CCRT (P = .015 and .003, respectively), while inducible T-cell costimulator (ICOS), B7-2, glucocorticoid-induced tumor necrosis factor receptor ligand (GITRL) increased at the end of CCRT (P = .032, .048, and .050, respectively). The other soluble immune checkpoint molecules including CD40 showed no significant change throughout CCRT (all P >0.05). Interestingly, we found that these changes were more significant in patients with CR than patients with PR/SD. Specifically, for patients with CR, levels of TIM-3 were significantly elevated both during and at the end of CCRT (P = .008 and < .001, respectively), while ICOS, B7-2, GITRL were significantly elevated at the end of CCRT (P = .023, .039, and .042, respectively). Meanwhile, CD40 was significantly elevated at the end of CCRT in patients with CR (P = .040). However, patients with PR/SD, no soluble immune checkpoint molecules were significantly changed (all P > 0.05). Our study reveals that CCRT could induce the elevation of the levels of soluble TIM-3, ICOS, B7-2, and GITRL in the blood of patients with LACC. This phenomenon was more obvious in patients with good response to CCRT.

Immune Co-inhibitory Receptors PD-1, CTLA-4, TIM-3, LAG-3, and TIGIT in Medullary Thyroid Cancers: A Large Cohort Study.

Programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte antigen 4 (CTLA-4), T-cell immunoglobulin and mucin-domain containing-3 (TIM-3), lymphocyte activation gene-3 (LAG-3), and T-cell immunoglobulin and ITIM domain (TIGIT) are considered major immune co-inhibitory receptors (CIRs) and the most promising immunotherapeutic targets in cancer treatment, but they are largely unexplored in medullary thyroid carcinoma (MTC). We aimed to provide the first evidence regarding the expression profiles and clinical significance of CIRs in a large cohort of MTC patients. In total, 200 MTC patients who received initial surgery in our hospital were included. Immunohistochemistry was performed to evaluate CIR expressions in tissue microarrays (TMAs). Combined with the results of our previous programmed cell death ligand-1 (PD-L1) study, clinicopathologic and prognostic correlations of these proteins were retrospectively analyzed. TIM-3, PD-1, CTLA-4, LAG-3, and TIGIT positivity was detected in 96 (48.0%), 27 (13.5%), 25 (12.5%), 6 (3.0%), and 6 (3.0%) patients, respectively, in whom TIM-3, PD-1, and CTLA-4 expressions were positively correlated. Log-rank tests and multivariate Cox analyses both indicated that TIM-3, CTLA-4 expression, and PD-1/PD-L1 coexpression were associated with worse structural recurrence-free survival. In addition, among 20 patients who developed advanced disease during follow-up, 12 (60%) showed TIM-3 positivity, among whom 6 cases also had concurrent moderate to strong PD-1, PD-L1, or CTLA-4 expression. Using the currently largest TMA cohort of this rare cancer, we delineated the CIR expression profiles in MTC, and identified TIM-3, CTLA-4 expression, and PD-1/PD-L1 coexpression as promising biomarkers for tumor recurrence. Furthermore, a subset of advanced MTCs are probably immunogenic, for which single or combined immunotherapy including TIM-3, PD-1, PD-L1, or CTLA-4 blockade may be potential therapeutic approaches in the future.

Abstract 933: Pre-clinical characterization of TIM-3 antibody NB002

Abstract Targeting immune checkpoint molecules PD1 and CTLA-4 by activating the immune system have improved the lives of many cancer patients. However, this type of immunotherapy is not effective for all patients, suggesting that there are additional mechanisms of immune evasion. T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) has been reported to be expressed on exhausted T and NK cells within the tumor microenvironment. The data in many preclinical models suggest that targeting TIM-3 pathway might provide an additional immune modulation of this anti-tumor axis in cancer patients. We have developed a novel monoclonal antibody NB002 against TIM-3,which forms a high-affinity interaction with a unique epitope. NB002 can enhance IFN-gamma secretion and proliferation of these exhausted T cells that has increased TIM-3 expression. Moreover, TIM-3 is constitutively expressed on NK cells. TIM-3 blockade could enhance in vitro cytotoxic activity of NK cells. Altogether, our data shows that NB002 is capable of targeting exhausted T cells and NK cells resulting activation of antitumor immunity. Further preclinical assessment in vivo and in vitro for solid tumors will support clinical development of NB002. Citation Format: Xin Dong, Jannie Dong, Jun Ma, Lianqi Zhao, Haojie Wang, Binbin Wang, Qian Gao, Hui Pan, Dong Wang, Liegang Shao. Pre-clinical characterization of TIM-3 antibody NB002 [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 933.

Immune Checkpoint Expression on Immune Cells of HNSCC Patients and Modulation by Chemo- and Immunotherapy.

Endogenous control mechanisms, including immune checkpoints and immunosuppressive cells, are exploited in the process of tumorigenesis to weaken the anti-tumor immune response. Cancer treatment by chemotherapy or immune checkpoint inhibition can lead to changes of checkpoint expression, which influences therapy success. Peripheral blood lymphocytes (PBL) and tumor-infiltrating lymphocytes (TIL) were isolated from head and neck squamous cell carcinoma (HNSCC) patients (n = 23) and compared to healthy donors (n = 23). Immune checkpoint expression (programmed cell death ligand 1 (PD-1), tumor necrosis factor receptor (TNFR)-related (GITR), CD137, tumor necrosis factor receptor superfamily member 4 (TNFRSF4) (OX40), t-cell immunoglobulin and mucin-domain containing-3 (TIM3), B- and T-lymphocyte attenuator (BTLA), lymphocyte-activation gene 3 (LAG3)) was determined on immune cells by flow cytometry. PD-L1 expression was detected on tumor tissue by immunohistochemistry. Immune cells were treated with immuno- and chemotherapeutics to investigate treatment-specific change in immune checkpoint expression, in vitro. Specific changes of immune checkpoint expression were identified on PBL and TIL of HNSCC patients compared to healthy donors. Various chemotherapeutics acted differently on the expression of immune checkpoints. Changes of checkpoint expression were significantly less pronounced on regulatory T cells compared to other lymphocyte populations. Nivolumab treatment significantly reduced the receptor PD-1 on all analyzed T cell populations, in vitro. The specific immune checkpoint expression patterns in HNSCC patients and the investigated effects of immunomodulatory agents may improve the development and efficacy of targeted immunotherapy.

Bgb-A425, an investigational anti-TIM-3 monoclonal antibody, in combination with tislelizumab, an anti-PD-1 monoclonal antibody, in patients with advanced solid tumors: A phase I/II trial in progress.

TPS3146 Background: While immune surveillance plays a critical role in preventing tumor proliferation and metastasis, tumors develop resistance mechanisms to suppress and/or escape the immune system. T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) and programmed cell death protein-1 (PD-1) function as immune checkpoint receptors on tumor-infiltrating lymphocytes. Overlap in expression and function suggests TIM-3 and PD-1 cooperate to maximize effector T-cell exhaustion, leading to a decreased antitumor immune response. Although blockade of TIM-3 alone is unlikely to result in an efficacious antitumor immune response, combined TIM-3/PD-1 blockade may enhance the antitumor properties of anti-PD-1 therapies alone. BGB-A425 is an investigational IgG1-variant monoclonal antibody against TIM-3. Tislelizumab, an anti-PD-1 antibody, was engineered to minimize binding to FcɣR on macrophages in order to abrogate antibody-dependent phagocytosis, a mechanism of T-cell clearance and potential resistance to anti-PD-1 therapy. This phase 1/2 study will assess the safety/tolerability, pharmacokinetic (PK) profile, and antitumor activity of BGB-A425 in combination with tislelizumab in patients with advanced solid tumors. Methods: This is an open-label phase 1/2 study (NCT03744468) of BGB-A425 in combination with tislelizumab in patients with histologically/cytologically confirmed advanced, metastatic, unresectable solid tumors. Phase 1 will determine the recommended phase 2 dose (RP2D) for combination treatment; phase 2 will assess the antitumor effects of the combination in select tumor types. In phase 1, up to 42 patients will be enrolled into sequential cohorts of increasing doses of intravenous (IV) BGB-A425 in combination with tislelizumab 200 mg IV, based on a 3+3 study design. During Cycle 1, patients will receive BGB-A425 alone on Day 1 followed by tislelizumab alone on Day 8. If no dose-limiting toxicities are observed, patients will receive both BGB-A425 and tislelizumab sequentially on Day 29 and every 21 days thereafter. Once the RP2D is determined, the combination therapy will be evaluated in up to 120 patients with select tumor types in phase 2. Safety/tolerability profile and RP2D determination (phase 1) and objective response rate per RECIST v1.1 (phase 2) are primary objectives; secondary objectives include antitumor activity, PK profile, and immunogenicity of combination therapy. Clinical trial information: NCT03744468 .