T cell immunoglobulin- and mucin-domain-containing molecule 3 gene polymorphisms and susceptibility to pancreatic cancer

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.

The Emerging Role of T-Cell Immunoglobulin Mucin-3 in Breast Cancer: A Promising Target For Immunotherapy

Cancer treatment through immune checkpoint receptor blockade has made significant advances in the recent years. However, resistance to the current immune checkpoint inhibitors (ICIs) has been observed in many patients, who consequently do not respond to these treatments. T-cell immunoglobulin mucin-3 (Tim-3) is a novel immune checkpoint molecule emerging as a potential therapeutic target for cancer immunotherapy. Epidemiologic findings reveal that genetic polymorphisms in the Tim-3 gene are associated with increased susceptibility to breast cancer. In patients with breast cancer, Tim-3 is expressed both on immune and tumor cells. Accumulating evidence demonstrates that Tim-3 can notably affect breast cancer treatment outcome and prognosis. Therefore, Tim-3 is being regarded as a high-potential target for improving breast cancer therapy. In this review, we summarize the role of Tim-3 in breast cancer and the regulation mechanisms of Tim-3 to furnish evidences for future research and therapy.

Structure and functions of T-cell immunoglobulin-domain and mucin- domain protein 3 in cancer

BACKGROUND

T-cell immunoglobulin (Ig)-domain and mucin-domain (TIM) proteins represent a family of receptors expressed on T-cells that play essential cellular immunity roles. The TIM proteins span across the membrane belonging to type I transmembrane proteins. The N terminus contains an Ig-like V-type domain and a Ser/Thr-rich mucin stalk as a co-inhibitory receptor. The C-terminal tail oriented toward the cytosol predominantly mediates intracellular signaling.

METHODS

This review discusses the structural features and functions of TIM-3, specifically on its role in mediating immune responses in different cell types, and the rationale for TIM-3-targeted cancer immunotherapy.

RESULTS

TIM-3 has gained significant importance to be a potential biomarker in cancer immunotherapy. It has been shown that blockade with checkpoint inhibitors promotes anti-tumor immunity and inhibits tumor growth in several preclinical tumor models.

CONCLUSION

TIM-3 is an immune regulating molecule expressed on several cell types, including IFNγ-producing T-cells, FoxP3+ Treg cells, and innate immune cells. The roles of TIM-3 in immunosuppression support its merit as a target for cancer immunotherapy.

The TIM-3 Rs10053538 Polymorphism Is Associated with Clinical Prognosis of Colorectal Cancer

Background: Genetic variants in the T cell immunoglobulin and mucin domain-containing molecule 3 (TIM-3) gene have been reported to be associated with the risk of cancers and patients' outcomes. The aims of this study were to explore the role of TIM-3 polymorphisms in the risk of colorectal cancer (CRC) and the prognosis of CRC patients in a northern Chinese population.Methods: Two polymorphisms of TIM-3 were genotyped using polymerase chain reaction and ligase detection reaction in 364 CRC patients and 372 healthy control subjects. The levels of TIM-3 mRNA were investigated in 65 CRC tissues by quantitative real-time PCR.Results: The results showed that neither rs10053538 nor rs10515746 was associated with susceptibility to CRC. However, the CA+AA genotypes of rs10053538 were related to an advanced clinical stage and increased risk of lymph nodemetastasis (P = .046 and 0.024, respectively). Multivariate analyses performed after adjusting for clinical variables showed that patients with the CA+AA genotypes of rs10053538 exhibited a significantly shorter disease-free survival (DFS) and overall survival (OS) time compared with those carrying the CC genotype (HR = 1.91, 95% CI = 1.04-3.51; HR = 2.61, 95% CI = 1.35-5.03). In addition, the expression of TIM-3 mRNA was significantly increased in the CRC tissues of patients carrying the rs10053538 CA+AA genotypes compared with patients carrying the CC genotype (P = .019).Conclusion: The rs10053538 may serve as an independent molecular marker for predicting the clinical outcome of CRC patients in the study population.

TIM-3 polymorphism is involved in the progression of esophageal squamous cell carcinoma by regulating gene expression

The T-cell immunoglobulin and mucin domain containing molecule 3 (TIM-3), a crucial immune regulatory molecule, is an emerging immune checkpoint target for cancer therapy. Our study aimed to investigate the association between TIM-3 polymorphisms (rs10053538 C > A, rs10515746 C > A, and rs1036199 A > C) and the susceptibility and prognosis of esophageal squamous cell carcinoma (ESCC). We further detect the effects of polymorphisms on TIM-3 expression. Two independent case-control sets (population-based and hospital-based sets) were performed in total 994 ESCC patients and 998 controls. TIM-3 polymorphisms were genotyped by polymerase chain reaction-ligase detection reaction (PCR). Survival data were available for 198 patients who received platinum-based chemotherapy after surgery. The regulation on TIM-3 expression by the polymorphisms was investigated in 35 patients using real-time quantitative PCR. The association between mRNA level of TIM-3 and survival was detected by using Kaplan-Meier plotter database. We found that for rs10053538 C > A polymorphisms, A allele was associated with significant increased risk of ESCC (odds ratios [OR] = 1.34, 95%CI = 1.05-1.72), and CA/AA genotypes enhanced susceptibility to ESCC for smokers (adjusted OR = 1.61, 95%CI = 1.00-2.59). The patients with AA genotypes had significantly poor prognosis (adjusted HR = 4.98, 95%CI = 1.14-21.71). The patients carrying CA/AA genotypes had significantly higher mRNA levels of TIM-3 than those carrying the CC genotype. Furthermore, high mRNA level of TIM-3 had a shorter overall survival in patients (HR = 2.56, 95%CI = 1.04-6.28). For rs10515746 C > A and rs1036199 A > C polymorphisms, there were no statistical correlation with the progression of ESCC. These data demonstrate that rs10053538 C > A polymorphisms may be associated with the susceptibility and prognosis of ESCC patients through regulating expression of TIM-3.

Immune Checkpoint Molecules-Inherited Variations as Markers for Cancer Risk

In recent years, immunotherapy has been revolutionized by a new approach that works by blocking receptors called immune checkpoints (IC). These molecules play a key role in maintaining immune homeostasis, mainly by suppressing the immune response and by preventing its overactivation. Since inhibition of the immune response by IC can be used by cancer to avoid recognition and destruction by immune system, blocking them enhances the anti-tumor response. This therapeutic approach has brought spectacular clinical effects. The ICs present heterogeneous expression patterns on immune cells, which may affect the effectiveness of immunotherapy. The inherited genetic variants in regulatory regions of ICs genes can be considered as potential factors responsible for observed inter-individual differences in ICs expression levels on immune cells. Additionally, polymorphism located in exons may introduce changes to ICs amino acid sequences with potential impact on functional properties of these molecules. Since genetic variants may affect both expression and structure of ICs, they are considered as risk factors of cancer development. Inherited genetic markers such as SNPs may also be useful in stratification patients into groups which will benefit from particular immunotherapy. In this review, we have comprehensively summarized the current understanding of the relationship between inherited variations of CTLA-4, PDCD1, PD-L1, BTLA, TIM-3, and LAG-3 genes in order to select SNPs which can be used as predictive biomarkers in personalized evaluation of cancer risk development and outcomes as well as possible response to immunotherapy.

Targeting novel inhibitory receptors in cancer immunotherapy

T cells play a critical role in promoting tumor regression in both experimental models and humans. Yet, T cells that are chronically exposed to tumor antigen during cancer progression can become dysfunctional/exhausted and fail to induce tumor destruction. Such tumor-induced T cell dysfunction may occur via multiple mechanisms. In particular, immune checkpoint inhibitory receptors that are upregulated by tumor-infiltrating lymphocytes in many cancers limit T cell survival and function. Overcoming this inhibitory receptor-mediated T cell dysfunction has been a central focus of recent developments in cancer immunotherapy. Immunotherapies targeting inhibitory receptor pathways such as programmed cell death 1 (PD-1)/programmed death ligand 1 and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4), alone or in combination, confer significant clinical benefits in multiple tumor types. However, many patients with cancer do not respond to immune checkpoint blockade, and dual PD-1/CTLA-4 blockade may cause serious adverse events, which limits its indications. Targeting novel non-redundant inhibitory receptor pathways contributing to tumor-induced T cell dysfunction in the tumor microenvironment may prove efficacious and non-toxic. This review presents preclinical and clinical findings supporting the roles of two key pathways-T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) and T cell immunoreceptor with Ig and ITIM domain (TIGIT)/CD226/CD96/CD112R-in cancer immunotherapy.

Distribution of novel immune-checkpoint targets in ovarian cancer tumor microenvironment: A dynamic landscape

BACKGROUND

The disappointing activity of single agent immune-checkpoint inhibitors in epitherlial ovarian cancer (EOC) has been attributed in part to its unique tumor microenvironment (TME). IDO, PDL1, LAG3 and TIM3 have been implicated in the immunotolerance of EOC. We investigated the expression of these co-regulators, their change with neoadjuvant chemotherapy (NACT), and their association with outcome.

METHOD

We identified 98 patients with EOC treated with NACT and performed IDO, PDL1, LAG3 and TIM3 immunohistochemistry on samples obtained before and after NACT. The cut-off threshold to consider a positive sample was set at 5%.

RESULTS

In our cohort, TIM3 was the most prevalent co-regulator, with more than 75% of the samples being TIM3 positive. In comparison, only 22%, 28% and 17% of the samples were considered IDO, PDL1 and LAG3 positive. More than half of ovarian tumors expressed 2, 3 or even all 4 co-inhibitory molecules. However, biomarkers were not correlated with each other. NACT had a marked impact on immune co-regulator expression with over 70% of patients showing a change in biomarker status from negative to positive or vice versa. There was no significant difference in the pattern of co-regulator expression between platinum-sensitive and resistant patients. Co-expression of multiple inhibitory molecules did not appear to affect overall and progression-free survival.

CONCLUSION

TIM3 is the most abundant co-inhibitory molecule in OC and may represent an attractive target. In addition, OC frequently co-expressed 2 or more markers supporting ICI combinatorial approaches. Finally, NACT significantly altered the expression of immunosuppressive molecules suggesting that the choice of ICI combinations should be adapted to the composition of the post-NACT immune TME.

Mechanisms of T-Cell Exhaustion in Pancreatic Cancer

T-cell exhaustion is a phenomenon that represents the dysfunctional state of T cells in chronic infections and cancer and is closely associated with poor prognosis in many cancers. The endogenous T-cell immunity and genetically edited cell therapies (CAR-T) failed to prevent tumor immune evasion. The effector T-cell activity is perturbed by an imbalance between inhibitory and stimulatory signals causing a reprogramming in metabolism and the high levels of multiple inhibitory receptors like programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), and Lymphocyte-activation gene 3 (Lag-3). Despite the efforts to neutralize inhibitory receptors by a single agent or combinatorial immune checkpoint inhibitors to boost effector function, PDAC remains unresponsive to these therapies, suggesting that multiple molecular mechanisms play a role in stimulating the exhaustion state of tumor-infiltrating T cells. Recent studies utilizing transcriptomics, mass cytometry, and epigenomics revealed a critical role of Thymocyte selection-associated high mobility group box protein (TOX) genes and TOX-associated pathways, driving T-cell exhaustion in chronic infection and cancer. Here, we will review recently defined molecular, genetic, and cellular factors that drive T-cell exhaustion in PDAC. We will also discuss the effects of available immune checkpoint inhibitors and the latest clinical trials targeting various molecular factors mediating T-cell exhaustion in PDAC.

Genetic variants and expression of the TIM-3 gene are associated with clinical prognosis in patients with epithelial ovarian cancer

OBJECTIVE

Polymorphisms of T cell immunoglobulin and mucin domain-containing molecule 3 (TIM-3) were reported to be associated with cancer risk and patients' survival. This study aims to investigate the correlation of TIM-3 polymorphisms with susceptibility to epithelial ovarian cancer (EOC) and patients' outcomes.

METHODS

A total of 700 EOC patients and 710 healthy controls from North China were included. The polymorphisms (rs10053538, rs10515746 and rs1036199) were genotyped using the polymerase chain reaction/ligase detection reaction (PCR-LDR) method. Survival data were available for 339 patients after cytoreductive surgery. The expression level of TIM-3 was detected by real-time quantitative PCR (RT-qPCR). The prognostic value of TIM3 in EOC patients was assessed using the Kaplan-Meier plotter database.

RESULTS

The results showed that none of the TIM3 polymorphisms were associated with the risk of developing EOC. Patients with the rs10053538 CA + AA genotype had worse PFS and OS than those with the CC genotype (HR = 1.49, 95% CI = 1.05-2.09, P = 0.024 and HR = 1.57, 95%CI = 1.09-2.26, P = 0.017, respectively). The RT-qPCR results showed that the expression levels of TIM-3 mRNA in EOC tissues with the rs10053538CA + AA genotypes were significantly higher than those with the CC genotype (P = 0.006). Analysis using the Kaplan-Meier plotter database showed that high expression of TIM-3 mRNA was significantly associated with shorter PFS and OS in EOC patients (HR = 1.57, 95%CI = 1.29-1.91, P < 0.001 and HR = 1.31, 95% CI = 1.06-1.63, P = 0.013, respectively).

CONCLUSIONS

TIM-3 polymorphisms were not associated with risk of developing EOC. Both rs10053538 and the expression level of TIM-3 mRNA may be associated with its clinical outcome in EOC patients.

The yin and yang of co-inhibitory receptors: toward anti-tumor immunity without autoimmunity

Co-inhibitory receptors are important regulators of T-cell function that define the balance between tolerance and autoimmunity. The immune regulatory function of co-inhibitory receptors, including CTLA-4, PD-1, TIM-3, TIGIT, and LAG-3, was first discovered in the setting of autoimmune disease models, in which their blockade or deficiency resulted in induction or exacerbation of the disease. Later on, co-inhibitory receptors on lymphocytes have also been found to influence outcomes in tumor and chronic viral infection settings. These receptors suppress T-cell function in the tumor microenvironment (TME), thereby making the T cells dysfunctional. Based on this observation, blockade of co-inhibitory receptors (also known as checkpoint molecules) has emerged as a successful treatment option for a number of human cancers. However, severe autoimmune-like side effects limit the use of therapeutics that block individual or combinations of co-inhibitory receptors for cancer treatment. In this review we provide an overview of the role of co-inhibitory receptors in autoimmunity and anti-tumor immunity. We then discuss current approaches and future directions to leverage our knowledge of co-inhibitory receptors to target them in tumor immunity without inducing autoimmunity.

TIM3 comes of age as an inhibitory receptor

T cell immunoglobulin and mucin domain-containing protein 3 (TIM3), a member of the TIM family, was originally identified as a receptor expressed on interferon-γ-producing CD4⁺ and CD8⁺ T cells. Initial data indicated that TIM3 functioned as a 'co-inhibitory' or 'checkpoint' receptor, but due to the lack of a definable inhibitory signalling motif, it was also suggested that TIM3 might act as a co-stimulatory receptor. Recent studies have shown that TIM3 is part of a module that contains multiple co-inhibitory receptors (checkpoint receptors), which are co-expressed and co-regulated on dysfunctional or 'exhausted' T cells in chronic viral infections and cancer. Furthermore, co-blockade of TIM3 and programmed cell death 1 (PD1) can result in tumour regression in preclinical models and can improve anticancer T cell responses in patients with advanced cancers. Here, we highlight the developments in understanding TIM3 biology, including novel ligand identification and the discovery of loss-of-function mutations associated with human disease. In addition, we summarize emerging data from human clinical trials showing that TIM3 indeed acts as a 'checkpoint' receptor and that inhibition of TIM3 enhances the antitumour effect of PD1 blockade.

Association between TIM-3 polymorphisms and cancer risk: a meta-analysis

BACKGROUND

Single nucleotide polymorphisms (SNPs) of T-cell immunoglobulin- and mucin-domain-containing molecule 3 (TIM-3) were reported to individually associate with cancer risk. To further verify its correlation with human cancers, we evaluated the association of TIM-3 polymorphisms and the risk of cancer.

METHODS

Data were collected from electronic databases. Two reviewers independently selected studies, extracted data and assessed quality of the studies. Data were meta-analyzed using the STATA 13.0 software. Crude odd ratio (OR) and 95% confidence interval was used to estimate the association between TIM-3 polymorphism and cancer susceptibility.

RESULTS

All eligible case-control studies included a total of 4,852 participants (2,229 cases and 2,623 controls). The meta-analysis showed that TIM-3 SNPs (-1516G/T, -574G/T, +4259T/G, and haplotypes) were significantly associated with an increased risk of susceptibility toward all cancers. The subgroup analyses based on cancer types showed that TIM-3 -1516G/T SNP was only associated with an increased risk in developing cancers in the digestive system or in hospital-based populations. Moreover, the TIM-3 -574G/T SNP was associated with an increased cancer risk in the digestive system or other systems, while TIM-3 +4259T/G SNP was only associated with an increased cancer risk in hospital-based populations. Among the four haplotypes observed (GGT, TGT, GGG, and GTT), The GGG haplotype showed an increase in the odds of cancer by 2.614-fold (OR 2.614; 95% CI: 1.756-3.893) compared with the GGT haplotype.

CONCLUSIONS

TIM-3 SNPs (-1516G/T, -574G/T, +4259T/G and the four haplotypes) were associated with an increased risk of developing human cancers.

Polymorphisms in TIM-3 and breast cancer susceptibility in Chinese women: A case-control study

Previous studies have found associations between polymorphisms in T cell immunoglobulin and mucin domain 3 (TIM-3) and increased risks of various cancers. However, the association between TIM-3 polymorphisms and breast cancer (BC) remains uncertain. In this study, a total of 560 BC patients and 583 age, sex, and ethnicity-matched healthy controls from Northwest China were included. The polymorphisms were genotyped using Sequenom MassARRAY. The expression level of TIM-3 protein was detected by immunohistochemistry. We observed rs10053538 had a significantly increased risk of BC, comparing with the wild-type genotype even after Bonferroni correction. In addition, the rs4704853 G>A variants were more frequent among BC patients than the controls (GA + AA vs. GG: OR = 1.32, 95% CI = 1.03-1.69, P = 0.026); However, the significance was lost after Bonferroni correction (P = 0.078). Furthermore, rs10053538 was associated with lymph node metastasis. Age stratification revealed that among patients aged <49 years, those with the rs4704853 GA/AA genotype had a higher risk of BC; But there was no difference when Bonferroni correction was conducted. Immunohistochemical analysis showed that the expression of TIM-3 protein in the breast cancer tissues was higher in patients carrying the rs10053538 GT+TT genotype than those with GG genotype (P = 0.012). However, we failed to find any difference between BC patients and controls in any rs1036199 genetic model. These findings suggested that rs10053538 in TIM-3 might increase susceptibility to BC and promote the progression of BC in Chinese women.

Quantitative assessment of TIM-3 polymorphisms and cancer risk in Chinese Han population

Previous studies have investigated the associations of TIM-3 polymorphisms (−1516G/T, −574G/T, and +4259T/G) with cancer risk in Chinese Han population, but the results remain conflicting. Therefore, we conducted a meta-analysis to derive a more precise estimation of the associations. The pooled data showed that TIM-3 polymorphisms (−1516G/T, −574G/T, and +4259T/G) were significantly associated with an increased risk of overall cancer in Chinese Han population. Subgroup analyses based on cancer system showed that TIM-3 −1516G/T polymorphism was only associated with an increased risk of digestive system cancer in Chinese Han population. TIM-3 −574G/T polymorphism was associated with an increased risk of digestive system cancer and other cancer in Chinese Han population. TIM-3 +4259T/G polymorphism was only associated with an increased risk of other cancer in Chinese Han population. In summary, our results indicated that TIM-3 polymorphisms (−1516G/T, −574G/T, and +4259T/G) were associated with the increased risk of cancer in Chinese Han population.

Emerging biomarkers for immunomodulatory cancer treatment of upper gastrointestinal, pancreatic and hepatic cancers

Carcinomas of the oesophagus, stomach, pancreas and liver are common and account for a disproportionately high number of cancer deaths. There is a need for new treatment options for patients with advanced disease. Immunomodulatory treatments including immune checkpoint blockade offer a promising new approach, with efficacy shown in other solid tumour types. However, only a small proportion of patients with carcinomas of the oesophagus, stomach, pancreas and liver have responded to single agent checkpoint inhibitors, and there is a need for markers that are predictive of response to guide treatment of individual patients. Predictive markers may include epidemiological factors such as ethnicity, the genomic status of the tumour, circulating markers, expression of immune checkpoint molecules, and other features of the stromal/immune response at the site of the tumour. This review will focus on predictive biomarkers for immune checkpoint blockade in oesophageal, gastric, pancreatic and hepatocellular carcinomas, including the genomic context and immune landscape in which they occur. Pancreatic carcinomas are largely resistant to immune checkpoint inhibition in trials to date, therefore emerging immunomodulatory treatments in this tumour type are also reviewed.

Immunotherapy as a treatment for biliary tract cancers: A review of approaches with an eye to the future

Biliary tract cancers (BTC) are aggressive malignancies associated with resistance to chemotherapy and poor prognostic rates. Therefore, novel treatment approaches are in need. Immunotherapy represents a promising breakthrough that uses a patient's immune system to target a tumor. This treatment approach has shown immense progress with positive results for selected cancers such as melanoma and nonsmall cell lung cancer. Initial preclinical data and preliminary clinical studies suggest encouraging mechanistic effects for immunotherapy in BTC offering the hope for an expanding therapeutic role for this disease. These approaches include targeted tumor antigen therapy via peptide and dendritic cell-based vaccines, allogenic cell adoptive immunotherapy, and the use of inhibitory agents targeting the immune checkpoint receptor pathway and multiple components of the tumor microenvironment. At this time demonstrating efficacy in larger clinical trials remains imperative. A multitude of ongoing trials aim to successfully translate mechanistic effects into antitumor efficacy and ultimately aim to incorporate immunotherapy into the routine management of BTC. With further research efforts, the optimization of dosing and therapeutic regimens, the identification of novel tumor antigens and a better understanding of alternative checkpoint pathway receptor expression may provide additional targets for rational combinatorial therapies which enhance the effects of immunotherapy and may offer hope for further advancing treatment options. Ultimately, the challenge remains to prospectively identify the subsets of patients with BTC who may respond to immunotherapy, and devising alternative strategies to sensitize those that do not with the hopes of improving outcomes for all with this deadly disease.

Ex Vivo PD-L1/PD-1 Pathway Blockade Reverses Dysfunction of Circulating CEA-Specific T Cells in Pancreatic Cancer Patients

Purpose: Carcinoembryonic antigen (CEA) is a candidate target for cellular immunotherapy of pancreatic cancer. In this study, we have characterized the antigen-specific function of autologous cytotoxic T lymphocytes (CTL) specific for the HLA-A2-restricted peptide, pCEA691-699, isolated from the peripheral T-cell repertoire of pancreatic cancer patients and sought to determine if ex vivo PD-L1 and TIM-3 blockade could enhance CTL function.Experimental Design: CD8⁺ T-cell lines were generated from peripheral blood mononuclear cells of 18 HLA-A2⁺ patients with pancreatic cancer and from 15 healthy controls. In vitro peptide-specific responses were evaluated by flow cytometry after staining for intracellular cytokine production and carboxy fluorescein succinimydyl ester cytotoxicity assays using pancreatic cancer cell lines as targets.Results: Cytokine-secreting functional CEA691-specific CTL lines were successfully generated from 10 of 18 pancreatic cancer patients, with two CTL lines able to recognize and kill both CEA691 peptide-loaded T2 cells and CEA⁺ HLA-A2⁺ pancreatic cancer cell lines. In the presence of ex vivo PD-L1 blockade, functional CEA691-specific CD8⁺ T-cell responses, including IFNγ secretion and proliferation, were enhanced, and this effect was more pronounced on Ag-specific T cells isolated from tumor draining lymph nodes.Conclusions: These data demonstrate that CEA691-specific CTL can be readily expanded from the self-restricted T-cell repertoire of pancreatic cancer patients and that their function can be enhanced by PD-L1 blockade. Clin Cancer Res; 23(20); 6178-89. ©2017 AACR.

Tim-3 and its role in regulating anti-tumor immunity

Immunotherapy is being increasingly recognized as a key therapeutic modality to treat cancer and represents one of the most exciting treatments for the disease. Fighting cancer with immunotherapy has revolutionized treatment for some patients and therapies targeting the immune checkpoint molecules such as CTLA-4 and PD-1 have achieved durable responses in melanoma, renal cancer, Hodgkin's diseases and lung cancer. However, the success rate of these treatments has been low and a large number of cancers, including colorectal cancer remain largely refractory to CTLA-4 and PD-1 blockade. This has provided impetus to identify other co-inhibitory receptors that could be exploited to enhance response rates of current immunotherapeutic agents and achieve responses to the cancers that are refectory to immunotherapy. Tim-3 is a co-inhibitory receptor that is expressed on IFN-g-producing T cells, FoxP3+ Treg cells and innate immune cells (macrophages and dendritic cells) where it has been shown to suppress their responses upon interaction with their ligand(s). Tim-3 has gained prominence as a potential candidate for cancer immunotherapy, where it has been shown that in vivo blockade of Tim-3 with other check-point inhibitors enhances anti-tumor immunity and suppresses tumor growth in several preclinical tumor models. This review discusses the recent findings on Tim-3, the role it plays in regulating immune responses in different cell types and the rationale for targeting Tim-3 for effective cancer immunotherapy.

Role of TIM-3 in ovarian cancer

Evidences have suggested that immunotherapy for ovarian cancer is effective. Immune checkpoints have emerged in the field of cancer immunotherapy. Multiple studies have shown negative regulation of TIM-3 expression on CD4⁺ and CD8⁺ T cells and other immunocytes. Overexpression of TIM-3 in innate immune cells has been found in certain types of tumor. The blockade of TIM-3 leads to sustained anti-tumor reactions. TIM-3 plays an inhibitive role for immunity in ovarian cancer. TIM-3 is involved in the development of various subtypes of ovarian cancer and thus has the potential to be a therapeutic target for treatment of ovarian cancer.

Investigation of T-cell immunoglobulin- and mucin-domain-containing molecule-3 (TIM-3) polymorphisms in essential thrombocythaemia (ET)

OBJECTIVES

T-cell immunoglobulin- and mucin-domain-containing molecule-3 (TIM-3) is preferentially expressed on terminally differentiated Th1 cells and inhibits their IFN-γ production. It has been reported that chronic inflammation may be an important driving force for myeloproliferative neoplasms (MPNs). Therefore, we hypothesized that as an important inflammation regulator, TIM-3 may be involved in essential thrombocythaemia (ET). The goal of this study was to investigate whether the -1516G > T, -574G > T and +4259T > G single-nucleotide polymorphisms (SNPs) within the TIM-3 gene contribute to the genetic susceptibility of individuals to ET.

METHODS

Genotyping of the TIM-3 -1516G > T, -574G > T and + 4259T > G SNPs was performed in 175 patients with ET and in 151 controls via a polymerase chain reaction-restriction fragment length polymorphism assay. We also investigated the relationships between the genotypes of each SNP and the risk factors of ET such as routine blood indexes, age and JAK2 V617F mutation.

RESULTS

The genotype and allele frequencies of the -1516G > T SNP (p = 0.016 and 0.019, respectively), the -574G > T SNP (p = 0.035 and 0.038, respectively) and the +4259T > G SNP (p = 0.036 and 0.038, respectively) of the ET patients and the controls were significantly different. A haplotype analysis found that the GGT and TGT haplotypes had significantly different distributions between ET and controls (p = 0.041 and 0.041, respectively). However, no significant differences were detected between the genotypes of all SNPs and routine blood indexes, age and JAK2V617F mutation.

CONCLUSION

The -1516G > T, -574G > T and +4259T > G SNPs within TIM-3 gene might play an important role as a genetic risk factor in the pathogenesis of ET.

Tim-3 and Tim-4 as the potential targets for antitumor therapy

Both Tim-3 and Tim-4 belong to the T-cell immunoglobulin and mucin domain (Tim) gene family, which plays a critical role in immunoregulation. Tim-3 has been suggested as a negative regulator of anti-tumor immunity due to its function on inducing T cells exhaustion in cancer. In addition to its expression on exhausted T cells, Tim-3 also has been reported to up-regulate on nature killer (NK) cells and promote NK cells functionally exhausted in cancer. While Tim-3 selectively expression on most types of leukemia stem cells, it promotes the progression of acute myeloid leukemia. Recently, data from experimental models of tumor discovered that Tim-3 and Tim-4 up-regulation on tumor associated dendritic cells and macrophages attenuated the anti-tumor effects of cancer vaccines and chemotherapy. Moreover, co-blockage of Tim-3 and PD-1, Tim-3 and CD137, Tim-3 and carcinoembryonic antigen cell adhesion molecule 1 (CEACAM1) could enhance cell-mediated immunity in advanced tumor, and combined treatment with anti-Tim-3 and anti-Tim-4 mAbs further increase the efficacy of cancer vaccines. The therapeutic manipulation of TIM-3 and TIM-4 may provide a novel strategy to improve the clinical efficacy of cancer immunotherapy.

Association and Intragenic Single-Nucleotide Polymorphism Interactions of the XRCC1 Polymorphisms for Pancreatic Cancer Susceptibility

OBJECTIVES

X-ray repair cross-complementing group 1 (XRCC1) gene is an important candidate gene for influencing human cancer risks. This study examined the main and interactive effect of 9 single-nucleotide polymorphisms (SNPs) (Arg194Trp, Arg280His, Arg399Gln, c.1254C>T, c.1517G>C, c.1471G>A, C310T, 539del542, and T1915C) of XRCC1 in contribution to pancreatic cancer (PC).

METHODS

A total of 298 PC patients and 298 healthy controls were enrolled. Selected SNPs in XRCC1 were genotyped. The generalized multifactor dimensionality reduction method investigated gene-gene interactions.

RESULTS

Single-locus analyses showed that, in the codominant model, the GO genotype of 539del542 might have a higher risk for PC (odds ratio [OR], 1.47; 95% confidence interval [95% CI], 1.05-2.08). For T1915C polymorphism, the TC and CC genotypes both had a higher risk for PC (OR, 1.76; 95% CI, 1.25-2.48; OR, 1.83; 95% CI, 1.05-3.19, respectively); and a similar result was observed in the dominant model (OR, 1.77; 95% CI, 1.28-2.46). A tendency of association between Arg280His and PC was also detected in the dominant model (OR, 0.70; 95% CI, 0.48-1.00). Furthermore, the generalized multifactor dimensionality reduction method showed that the 4-locus model was significant, involving Arg280His, 539del542, T1915C, and c.1517G>C (P < 0.05).

CONCLUSIONS

Thus, XRCC1 polymorphisms may contribute to the risk of PC independently or in an interactive manner.

From bench to bedside a comprehensive review of pancreatic cancer immunotherapy

The incidence of pancreatic cancer has been increasing while its 5-year survival rate has not changed in decades. In the era of personalized medicine, immunotherapy has emerged as a promising treatment modality in a variety of malignancies, including pancreatic cancer. This review will discuss the unique pancreatic tumor microenvironment, including the cells and receptors that transform the pancreas from its normal architecture into a complex mix of suppressor immune cells and dense extracellular matrix that allows for the unrestricted growth of cancer cells. Next, we will highlight the recently completed immunotherapy clinical trials in pancreatic cancer. Finally, we will explore the on-going immunotherapy clinical trials and future directions of this engaging and changing field.

Emerging immune checkpoints for cancer therapy

BACKGROUND

Immunotherapy with immune checkpoint inhibitors has emerged as promising treatment modality for cancer based on the success of anti-CTLA-4 and -PD-1/PD-L1 antibodies. LAG-3 and TIM-3 are two new immune checkpoints. The aim of this work is to review the role and application of LAG-3 and TIM-3 for cancer immunotherapy.

MATERIAL AND METHODS

Literatures were searched and collected in Medline/PubMed.

RESULTS

LAG-3 is presented as a CD4 homolog type I transmembrane protein which binds MHC class II molecules. LAG-3 negatively regulates T cell proliferation, homeostasis and function. IMP321 is formed of an extracellular portion of human LAG-3 fused to the Fc fraction of human IgG1 and has shown increased T cell responses and tolerability in phase I studies on advanced renal cell cancer. When combined with paclitaxel, IMP321 has exerted immune enhancement and tumor inhibition with no significant IMP321-related adverse events. TIM-3 belongs to the TIM family and mainly negatively regulates Th1 immunity. The TIM-3/galectin-9 pathway contributes to the suppressive tumor microenvironment. TIM-3 overexpression is associated with poor prognosis in a variety of cancers. Both LAG-3 and TIM-3 are coexpressed with other immune checkpoints. The application of LAG-3 or TIM-3 does play an important role in anti-tumor responses, and maybe better when combing with anti-CTLA-4 and anti-PD-1/L1 antibodies.

CONCLUSIONS

These two immune checkpoints play crucial roles in cancer development and may be used in future clinical practice of cancer therapy.

Association between polymorphisms in the promoter region of T cell immunoglobulin and mucin domain-3 and myasthenia gravis-associated thymoma

Thymoma is a type of benign or low-grade malignant tumor, occurring on the thymic epithelium. Patients with thymoma may also suffer from myasthenia gravis (MG), presenting MG-associated thymoma. T cell immunoglobulin and mucin domain-3 (Tim-3), a subtype of the Tim protein family, may be an important immune regulatory and pivotal molecule associated with tumor development. In order to understand the etiology and pathogenesis of MG-associated thymoma in the Han population of North China, the present study investigated the association between a polymorphism on the -574 locus in the promoter of Tim-3 and the risk of MG-associated thymoma in the Han Chinese population. In total, 116 patients with thymoma and MG were enrolled into the MG-associated thymoma group, while 124 patients with thymoma, but without MG, were enrolled into the non-MG-associated thymoma group. Examinations were conducted to reach a definite diagnosis of thymoma and MG and rule out other autoimmune diseases. Allele-specific polymerase chain reaction (AS-PCR) was performed to determine the polymorphism on the -574 locus of Tim-3 in all the subjects. PCR products were randomly selected for sequencing. Statistically significant differences were detected between the distribution frequencies of the GT+TT genotype and T allele on the -574 locus of the MG-associated thymoma group (31.03 vs. 12.90%, respectively; χ²=11.609, P=0.001) and the non-MG-associated thymoma group (15.52 vs. 6.45%, respectively; χ²=10.198, P=0.001). In conclusion, the present study indicated that an association may exist between the polymorphism of the -574 locus in the Tim-3 promoter and MG-associated thymoma.

Tim-3 polymorphism downregulates gene expression and is involved in the susceptibility to ankylosing spondylitis

Ankylosing spondylitis (AS) is a chronic inflammatory disorder primarily affecting the sacroiliac joints and the spine. T-cell immunoglobulin- and mucin-domain-containing molecule 3 (TIM-3) has been established as a negative regulatory molecule that plays a critical role in controlling inflammation. Studies have shown that polymorphisms in TIM-3 gene may be associated with inflammatory diseases. The current study investigated the association between polymorphisms in the TIM-3 gene and susceptibility to AS, and it examined the effects of these polymorphisms on gene expression. Two polymorphisms in TIM-3 -574G/T and +4259T/G polymorphisms were identified by polymerase chain reaction-restriction fragment length polymorphism in 282 AS patients and 298 healthy controls. Results showed that frequency of the TIM-3 -574GT genotype was significantly increased in cases than in controls (Odd ratio [OR]=2.50, 95% confidence interval [CI]: 1.39-4.48, p=0.002). Similarly, TIM-3 -574T allele revealed a positive association with the disease (OR=2.39, p=0.002). The TIM-3 +4259T/G polymorphism did not show any correlation with AS. We further evaluated TIM-3 mRNA and protein levels in CD4(+) T cells, CD8(+) T cells, and monocytes from subjects carrying different TIM-3 genotypes. Results revealed that subjects carrying polymorphic -574GT genotype had significantly lower TIM-3 mRNA and protein levels in CD4(+) T cells, CD8(+) T cells, and monocytes than those with wild-type GG genotype. These data suggest that TIM-3 polymorphism is associated with increased susceptibility to AS possibly by downregulating gene expression.

T-cell immunoglobulin- and mucin-domain-containing molecule 3 genetic variants and HIV+ non-Hodgkin lymphomas

T cell immunoglobulin- and mucin-domain-containing molecule 3 (TIM-3) has been established as a negative regulatory molecule and plays a critical role in inflammatory diseases such as rheumatoid arthritis, hepatitis B and C, and human immunodeficiency virus (HIV)-related inflammation. Recent studies have shown that chronic inflammation may greatly affect the pathogenesis of non-Hodgkin lymphomas (NHL). The aim of this study was to investigate whether polymorphisms in the TIM-3 gene were associated with susceptibility to non-NHL and HIV-related NHL. Three polymorphisms in TIM-3 gene (-1516G/T, -574G/T, and +4259T/G) were identified by polymerase chain reaction-restriction fragment length polymorphism in 434 NHL patients, 62 HIV-related NHL cases, and 512 healthy controls. Results showed that the prevalence of -574GT genotype and +4259TG genotype were significantly increased in the NHL cases than in controls (odds ratio (OR) = 2.72, 95% confidence interval (CI) = 1.50-4.92, p = 0.0006 and OR = 2.59, 95% CI = 1.49-4.49, p = 0.0005, respectively). The -1516G/T polymorphism did not reveal significant difference between patients and healthy controls. When analyzing the TIM-3 polymorphisms in HIV-related NHL patients, data showed that HIV+ NHL patients had higher prevalence of -574GT or +4259TG genotypes than those cases without HIV infection (OR = 3.48, 95% CI = 1.67-7.28, p = 0.0005 and OR = 2.92, 95% CI = 1.42-6.01, p = 0.0026, respectively). These results suggested polymorphisms in TIM-3 gene could be new risk factors for NHL as well as HIV-related NHL and suggested a possible role of the inflammatory factor in these diseases.

The relationship between polymorphisms in the promoter region of Tim-3 and unexplained recurrent spontaneous abortion in Han Chinese women

BACKGROUND

Recurrent spontaneous abortion (RSA) refers to 2 or more consecutive pregnancy losses, and RSA with unknown causes is called unexplained recurrent spontaneous abortion (URSA). Tim-3, a subtype of the T-cell immunoglobulin domain and mucin domain (Tim) protein family, might be an important regulatory molecule that plays a pivotal role in URSA, which might be triggered mostly by Th1/Th2 immune deviation. To understand the etiology and pathogenesis of URSA in Han Chinese women, we investigated the association between polymorphisms of rs10053538 and rs10515746 in the promoter of Tim-3 and the risk of URSA in Han Chinese women.

METHODS

One hundred and forty-eight women with RSA resulting in still birth were enrolled in the URSA group. We performed tests to rule out congenital reproductive system malformation, reproductive system tumor, endocrine dyscrasia, and chromosome abnormalities. One hundred and fifty-three women with normal pregnancy leading to live birth were selected at random to comprise the control group. All women included in this study were genetically unrelated Han Chinese women. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and allele-specific polymerase chain reaction (AS-PCR) were used to determine polymorphisms of rs10053538 and rs10515746, respectively, in all subjects. PCR products were chosen at random for sequencing.

RESULTS

No significant statistical difference was found between the distribution frequency of the GT + TT genotype and T allele on the rs10053538 locus in the URSA group or the control group (10.1% vs. 11.8%, Chi(2) = 0.205, P = 0.651; 5.1% vs. 6.5%, Chi(2) = 0.592, P = 0.441; respectively). Neither was there a significant difference between the distribution frequency of the GT + TT genotype and T allele on the rs10515746 locus in the groups (6.8% vs. 3.9%, Chi(2)1.201, P = 0.273; 3.4% vs. 2.0%, Chi(2) = 1.169, P = 0.280; respectively).

CONCLUSIONS

The present study suggested that these polymorphisms of rs10053538 or rs10515746 in the Tim-3 promoter may not be associated with URSA in Han Chinese women.

Significant association between GSTT1 null genotype and susceptibility to pancreatic cancer

Many studies have investigated the association between glutathione S-transferase T1 (GSTT1) polymorphism and risk for pancreatic cancer, but those studies have yielded contradictory findings on the association. We performed a comprehensive search in the PubMed, EMBASE, and the Chinese National Knowledge Infrastructure databases to identify relevant studies. A meta-analysis was performed to examine the association between GSTT1 polymorphism and susceptibility to pancreatic cancer by calculating the pooled odds ratios (ORs) and corresponding 95 % confidence intervals (95 % CIs). Eight studies involving a total of 4,437 individuals were included. Overall, significantly increased pancreatic cancer risk was associated with GSTT1 null genotype when all studies were pooled into the meta-analysis (random effects OR = 1.61, 95 % CI 1.06-2.44; P = 0.025). Significantly increased risk of pancreatic cancer was also found for GSTT1 null genotype in Asians when stratified by ethnicity (fixed effects OR = 2.67, 95 % CI 1.74-4.09; P < 0.001). The findings demonstrate that GSTT1 null genotype have a modest effect on the genetic susceptibility to pancreatic cancer, and GSTT1 null genotype is associated with increased risk of pancreatic cancer.

Cancer targeting gene-viro-therapy for pancreatic cancer using oncolytic adenovirus ZD55-IL-24 in immune-competent mice

Cancer targeting gene-viro-therapy (CTGVT) may prove to be an effective treatment for pancreatic cancer (PC). This study was intended to explore the anti-tumor effect of ZD55-IL-24 (oncolytic adenovirus ZD55 harboring IL-24) on PC in immune-competent mice. The expression of gene harbored by oncolytic adenovirus ZD55 in PC cells was detected by reporter-gene assays. The in vitro anti PC ability of ZD55-IL-24 was tested by MTT, crystal violet staining and apoptosis assays. The in vivo anti PC effect of ZD55-IL-24 was further observed in an immune-competent mice model by detecting anti-tumor immunity and induction of apoptosis. The expression of gene harbored by ZD55 in PC cells was significantly higher than that harbored by the replicated-deficient adenovirus, and the amount of gene expression was time-dependent and dose-dependent. Both ZD55-IL-24 and ZD55 inhibited PC cells growth, but the anti-tumor effect of ZD55-IL-24 was significantly stronger than that of ZD55, and the ability of ZD55-IL-24 in inducing PC apoptosis was significantly stronger than that of ZD55. The tumor-forming rate of group ZD55-IL-24 was the lowest, and the tumor-growing rate was also significantly lower than that of group ZD55 in immune-competent PC models. Moreover, ZD55-IL-24 mediated more anti-cancer immunity effects by induction of stronger T-lymphocytes response to PC cells, higher levels of γ-IFN and IL-6 cytokines. ZD55-IL-24-mediated CTGVT could inhibit PC growth not only by inducing oncolysis and apoptosis but enhancing the anti-cancer immune effects by inducing T cell response to PC and up-regulating γ-IFN and IL-6 cytokine in immune-competent mice. This may serve as a candidate therapeutic approach for the treatment of PC.

Galectin-9 increases Tim-3+ dendritic cells and CD8+ T cells and enhances antitumor immunity via galectin-9-Tim-3 interactions

A Tim-3 ligand, galectin-9 (Gal-9), modulates various functions of innate and adaptive immune responses. In this study, we demonstrate that Gal-9 prolongs the survival of Meth-A tumor-bearing mice in a dose- and time-dependent manner. Although Gal-9 did not prolong the survival of tumor-bearing nude mice, transfer of naive spleen cells restored a prolonged Gal-9-induced survival in nude mice, indicating possible involvement of T cell-mediated immune responses in Gal-9-mediated antitumor activity. Gal-9 administration increased the number of IFN-gamma-producing Tim-3(+) CD8(+) T cells with enhanced granzyme B and perforin expression, although it induced CD4(+) T cell apoptosis. It simultaneously increased the number of Tim-3(+)CD86(+) mature dendritic cells (DCs) in vivo and in vitro. Coculture of CD8(+) T cells with DCs from Gal-9-treated mice increased the number of IFN-gamma producing cells and IFN-gamma production. Depletion of Tim-3(+) DCs from DCs of Gal-9-treated tumor-bearing mice decreased the number of IFN-gamma-producing CD8(+) T cells. Such DC activity was significantly abrogated by Tim-3-Ig, suggesting that Gal-9 potentiates CD8(+) T cell-mediated antitumor immunity via Gal-9-Tim-3 interactions between DCs and CD8(+) T cells.