TIM-3 promotes the metastasis of esophageal squamous cell carcinoma by targeting epithelial-mesenchymal transition via the Akt/GSK-3β/Snail signaling pathway

Integrative Analysis of Histone Acetylation Regulated CYP4F12 in Esophageal Cancer Development

Current therapeutic strategies for esophageal cancer (EC) patients have yielded limited improvements in survival rates. Recent research has highlighted the influence of drug metabolism enzymes on both drug response and EC development. Our study aims to identify specific drug metabolism enzymes regulated by histone acetylation and to elucidate its molecular and clinical features. CYP4F12 exhibited a notable upregulation subsequent to trichostatin A treatment as evidenced by RNA sequencing analysis conducted on the KYSE-150 cell line. The change in gene expression was associated with increased acetylation level of histone 3 K18 and K27 in the promoter. The regulation was dependent on p300. In silicon analysis of both The Cancer Genome Atlas esophageal carcinoma and GSE53624 dataset suggested a critical role of CYP4F12 in EC development, because CYP4F12 was downregulated in tumor tissues and predicted better disease-free survival. Gene ontology analysis has uncovered a robust correlation between CYP4F12 and processes related to cell migration, as well as its involvement in cytosine-mediated immune activities. Further investigation into the relationship between immune cells and CYP4F12 expression has indicated an increased level of B cell infiltration in samples with high CYP4F12 expression. CYP4F12 was also negatively correlated with the expression of inhibitory checkpoints. An accurate predictive nomogram model was established combining with clinical factors and CYP4F12 expression. In conclusion, CYP4F12 was crucial in EC development, and targeting CYP4F12 may improve the therapeutic efficacy of current treatment in EC patients. SIGNIFICANCE STATEMENT: CYP4F12 expression was downregulated in esophageal cancer (EC) patients and could be induced by trichostatin A. During EC development, CYP4F12 was linked to reduced cell migration and increased infiltration of B cells. CYP4F12 also is a biomarker as prognostic predictors and therapeutic guide in EC patients.

Immune checkpoints between epithelial-mesenchymal transition and autophagy: A conflicting triangle

Inhibitory immune checkpoint (ICP) molecules are pivotal in inhibiting innate and acquired antitumor immune responses, a mechanism frequently exploited by cancer cells to evade host immunity. These evasion strategies contribute to the complexity of cancer progression and therapeutic resistance. For this reason, ICP molecules have become targets for antitumor drugs, particularly monoclonal antibodies, collectively referred to as immune checkpoint inhibitors (ICI), that counteract such cancer-associated immune suppression and restore antitumor immune responses. Over the last decade, however, it has become clear that tumor cell-associated ICPs can also induce tumor cell-intrinsic effects, in particular epithelial-mesenchymal transition (EMT) and macroautophagy (hereafter autophagy). Both of these processes have profound implications for cancer metastasis and drug responsiveness. This article reviews the positive or negative cross-talk that tumor cell-associated ICPs undergo with autophagy and EMT. We discuss that tumor cell-associated ICPs are upregulated in response to the same stimuli that induce EMT. Moreover, ICPs themselves, when overexpressed, become an EMT-inducing stimulus. As regards the cross-talk with autophagy, ICPs have been shown to either stimulate or inhibit autophagy, while autophagy itself can either up- or downregulate the expression of ICPs. This dynamic equilibrium also extends to the autophagy-apoptosis axis, further emphasizing the complexities of cellular responses. Eventually, we delve into the intricate balance between autophagy and apoptosis, elucidating its role in the broader interplay of cellular dynamics influenced by ICPs. In the final part of this article, we speculate about the driving forces underlying the contradictory outcomes of the reciprocal, inhibitory, or stimulatory effects between ICPs, EMT, and autophagy. A conclusive identification of these driving forces may allow to achieve improved antitumor effects when using combinations of ICIs and compounds acting on EMT and/or autophagy. Prospectively, this may translate into increased and/or broadened therapeutic efficacy compared to what is currently achieved with ICI-based clinical protocols.

Potential markers of cancer stem-like cells in ESCC: a review of the current knowledge

In patients with esophageal squamous cell carcinoma (ESCC), the incidence and mortality rate of ESCC in our country are also higher than those in the rest of the world. Despite advances in the treatment department method, patient survival rates have not obviously improved, which often leads to treatment obstruction and cancer repeat. ESCC has special cells called cancer stem-like cells (CSLCs) with self-renewal and differentiation ability, which reflect the development process and prognosis of cancer. In this review, we evaluated CSLCs, which are identified from the expression of cell surface markers in ESCC. By inciting EMTs to participate in tumor migration and invasion, stem cells promote tumor redifferentiation. Some factors can inhibit the migration and invasion of ESCC via the EMT-related pathway. We here summarize the research progress on the surface markers of CSLCs, EMT pathway, and the microenvironment in the process of tumor growth. Thus, these data may be more valuable for clinical applications.

TIM-3 regulates the proliferation by BDNF-mediated PI3K/AKT axis in the process of endometriosis

BACKGROUND

T cell immunoglobulin and mucin domain-containing molecule-3 (TIM-3) initially discovered on the surface of Th1 cells, negatively regulates immune responses and mediates apoptosis of Th1 cells. An increasing number of studies have since shown that TIM-3 is crucial in the genesis and development of immune diseases, cancers, and chronic infectious illnesses. However, the effect of TIM-3 on endometriosis is still unknown.

METHODS

Quantitative real-time polymerase chain reaction, western blotting, and immunohistochemistry were used to measure TIM-3 levels in endometriosis. Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine, colony-forming, Transwell® migration, Matrigel® invasion, and flow cytometry assays were used to explore the function of TIM-3 in vitro, and xenograft experiments in nude mice were used to assess its role in vivo. According to the RNA seq, brain-derived neurotrophic factor (BDNF) was screened. The involvement of specific proliferation-related signaling molecules was determined by transfecting a plasmid and adding an inhibitor in vivo and in vitro.

RESULTS

TIM-3 mRNA and protein expression levels were significantly higher in eutopic and ectopic endometrial tissues than in normal endometrial tissues. By examining the effects of TIM-3 overexpression and knockdown on cell proliferation, migration, and invasion in vitro, and lesions formation in vivo, we found that the expression of TIM-3 was positively correlated with cell proliferation and clone formation in vitro, as well as lesions growth in nude mice. By adding the phosphatidylinositol 3 kinase/protein kinase B(PI3K/AKT) pathway inhibitor LY294002 and knocking down PI3K, we further verified that TIM-3 promotes proliferation in vivo and in vitro via the PI3K pathway. By transfecting the plasmid into ESC cells and gave inhibitors to endometriotic rats models, we tested that TIM-3 regulates the proliferation by BDNF-mediated PI3K/AKT axis.

CONCLUSION

TIM-3 can promote the proliferation of endometriosis by BDNF-mediated PI3K/AKT axis in vivo and in vitro, which may provide a new therapeutic target for the treatment of endometriosis.

Prognostic value of T cell immunoglobulin and mucin-domain containing-3 expression in upper gastrointestinal tract tumors: A meta-analysis

BACKGROUND

There is a lack of robust prognostic markers for upper gastrointestinal (GI) tract cancers, including esophageal, gastric, and esophagogastric junction cancers. T cell immunoglobulin and mucin-domain containing-3 (TIM3) plays a key immunomodulatory role and is linked to the prognosis of various cancers. However, the significance of TIM3 in upper GI tract tumors is still uncertain.

AIM

To investigate the prognostic value of TIM3 expression in upper GI tract tumors.

METHODS

A literature search was conducted on the PubMed, Embase, and Web of Science databases for relevant studies published until June 2023. After screening and quality assessment, studies that met the criteria were included in the meta-analysis. Statistical methods were used for the pooled analysis to assess the association of TIM3 expression in upper GI tract tumors with the prognosis and clinicopathological parameters. The results were reported with the hazard ratio (HR) and 95% confidence interval (CI).

RESULTS

Nine studies involving 2556 patients with upper GI tract cancer were included. High TIM3 expression was associated with a worse prognosis in upper GI tract cancer (HR: 1.17, 95%CI: 1.01-1.36). Positive expression of TIM3 in gastric cancer was correlated with the T and N stage, but the difference was not statistically significant. However, TIM3 overexpression was significantly correlated with the TNM stage (odds ratio: 1.21, 95%CI: 0.63-2.33; P < 0.05). TIM3 expression showed no association with the other clinicopathological parameters.

CONCLUSION

High expression of TIM3 in the upper GI tract cancer is associated with a worse prognosis and advanced T or N stages, indicating its potential value as a prognostic biomarker. These findings may provide a basis for the personalized treatment of upper GI tract cancers.

The transcriptome signature analysis of the epithelial-mesenchymal transition and immune cell infiltration in colon adenocarcinoma

The epithelial-mesenchymal transition (EMT) process is tightly connected to tumors' immune microenvironment. In colon adenocarcinoma (COAD), both the EMT and immune cell infiltration contribute to tumor progression; however, several questions regarding the mechanisms governing the interaction between EMT and the immune response remain unanswered. Our study aims to investigate the cross-talk between these two processes in cases of COAD and identify the key regulators involved. We utilized the EMT and immune signatures of samples from the COAD-TCGA database to identify three subtypes of COAD: high mesenchymal, medium mesenchymal, and low mesenchymal. We observed that EMT was associated with increased tumor immune response and infiltration mediated by pro-inflammatory cytokines. However, EMT was also linked to immunosuppressive activity that involved regulatory T cells, dendritic cells, and the upregulated expression of multiple immune checkpoints, such as PD-1, PDL-1, CTLA-4, and others. Finally, we employed the multivariate random forest feature importance method to identify key genes, such as DOK2 and MSRB3, that may play crucial roles in both EMT and the intratumoral immune response.

Non-invasive molecular imaging for precision diagnosis of metastatic lymph nodes: opportunities from preclinical to clinical applications

Lymph node metastasis is an indicator of the invasiveness and aggressiveness of cancer. It is a vital prognostic factor in clinical staging of the disease and therapeutic decision-making. Patients with positive metastatic lymph nodes are likely to develop recurrent disease, distant metastasis, and succumb to death in the coming few years. Lymph node dissection and histological analysis are needed to detect whether regional lymph nodes have been infiltrated by cancer cells and determine the likely outcome of treatment and the patient's chances of survival. However, these procedures are invasive, and tissue biopsies are prone to sampling error. In recent years, advanced molecular imaging with novel imaging probes has provided new technologies that are contributing to comprehensive management of cancer, including non-invasive investigation of lymphatic drainage from tumors, identifying metastatic lymph nodes, and guiding surgeons to operate efficiently in patients with complex lesions. In this review, first, we outline the current status of different molecular imaging modalities applied for lymph node metastasis management. Second, we summarize the multi-functional imaging probes applied with the different imaging modalities as well as applications of cancer lymph node metastasis from preclinical studies to clinical translations. Third, we describe the limitations that must be considered in the field of molecular imaging for improved detection of lymph node metastasis. Finally, we propose future directions for molecular imaging technology that will allow more personalized treatment plans for patients with lymph node metastasis.

Cystathionine γ-lyase mediates cell proliferation, migration, and invasion of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is an epithelia-derived malignancy with a distinctive geographic distribution. Cystathionine γ-lyase (CSE) is involved in cancer development and progression. Nevertheless, the role of CSE in the growth of NPC is unknown. In this study, we found that CSE levels in human NPC cells were higher than those in normal nasopharyngeal cells. CSE overexpression enhanced the proliferative, migrative, and invasive abilities of NPC cells and CSE downregulation exerted reverse effects. Overexpression of CSE decreased the expressions of cytochrome C, cleaved caspase (cas)-3, cleaved cas-9, and cleaved poly-ADP-ribose polymerase, whereas CSE knockdown exhibited reverse effects. CSE overexpression decreased reactive oxygen species (ROS) levels and the expressions of phospho (p)-extracellular signal-regulated protein kinase 1/2, p-c-Jun N-terminal kinase, and p-p38, but promoted the expressions of p-phosphatidylinositol 3-kinase (PI3K), p-AKT, and p-mammalian target of rapamycin (mTOR), whereas CSE knockdown showed oppose effects. In addition, CSE overexpression promoted NPC xenograft tumor growth and CSE knockdown decreased tumor growth by modulating proliferation, angiogenesis, cell cycle, and apoptosis. Furthermore, DL-propargylglycine (an inhibitor of CSE) dose-dependently inhibited NPC cell growth via ROS-mediated mitogen-activated protein kinase (MAPK) and PI3K/AKT/mTOR pathways without significant toxicity. In conclusion, CSE could regulate the growth of NPC cells through ROS-mediated MAPK and PI3K/AKT/mTOR cascades. CSE might be a novel tumor marker for the diagnosis and prognosis of NPC. Novel donors/drugs that inhibit the expression/activity of CSE can be developed in the treatment of NPC.

Current and Future Immunotherapy-Based Treatments for Oesophageal Cancers

Oesophageal cancer is a disease that causes significant morbidity and mortality worldwide, and the prognosis of this condition has hardly improved in the past few years. Standard treatment includes a combination of chemotherapy, radiotherapy and surgery; however, only a proportion of patients go on to treatment intended to cure the disease due to the late presentation of this disease. New treatment options are of utmost importance, and immunotherapy is a new option that has the potential to transform the landscape of this disease. This treatment is developed to act on the changes within the immune system caused by cancer, including checkpoint inhibitors, which have recently shown great promise in the treatment of this disease and have recently been included in the adjuvant treatment of oesophageal cancer in many countries worldwide. This review will outline the mechanisms by which cancer evades the immune system in those diagnosed with oesophageal cancer and will summarize current and ongoing trials that focus on the use of our own immune system to combat disease.

HuR Affects the Radiosensitivity of Esophageal Cancer by Regulating the EMT-Related Protein Snail

Purpose

We previously found that Hu antigen R (HuR) can regulate the proliferation and metastasis of esophageal cancer cells. This study aims to explore the effects of HuR on the radiosensitivity of esophageal cancer.

Materials and Method

Analyses of CCK-8, colony formation assay, Western blot, immunofluorescence, flow cytometry, reactive oxygen species (ROS), and mitochondrial membrane potential were conducted to characterize the esophageal cancer cells. Nude mouse models were used to detect the effects of HuR in a combination of X-ray treatment on the subcutaneous xenografts of esophageal cancer. In addition, a luciferase assay was used to detect the direct interaction of HuR with Snail mRNA 3’-UTR.

Results

The down-regulation of HuR combined with X-ray can significantly inhibit the proliferation and colony formation of esophageal cancer cells. Flow cytometry data showed that the down-regulation of HuR could induce a G1 phase cell cycle block in esophageal cancer cells, and aggravate X-ray-induced apoptosis, indicated by the increases of apoptosis-related proteins Bax, caspase-3 and caspase-9. Moreover, the down-regulation of HuR could significantly impair the mitochondrial membrane potential and increase the ROS production and DNA double-strand break marker γH2AX expression in esophageal cancer cells that were exposed to X-rays. In vivo data showed that the down-regulation of HuR combined with radiation significantly decreased the growth of subcutaneous xenograft tumors. Furthermore, HuR could interact with Snail. Up-regulation of Snail can reverse the EMT inhibitory effects caused by HuR down-regulation, and attenuate the tumor-inhibiting and radiosensitizing effects caused by HuR down-regulation.

Conclusion

In summary, our data demonstrate that HuR effectively regulates the radiosensitivity of esophageal cancer, which may be achieved by stabilizing Snail. Thus, HuR/Snail axis is a potentially therapeutic target for the treatment of esophageal cancer.

PI3K/Akt/mTOR Signaling Pathway: Role in Esophageal Squamous Cell Carcinoma, Regulatory Mechanisms and Opportunities for Targeted Therapy

Esophageal squamous cell carcinoma (ESCC), is the most common type of esophageal cancer worldwide, mainly occurring in the Asian esophageal cancer belt, including northern China, Iran, and parts of Africa. Phosphatidlinositol 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway is one of the most important cellular signaling pathways, which plays a crucial role in the regulation of cell growth, differentiation, migration, metabolism and proliferation. In addition, mutations in some molecules of PI3K/Akt/mTOR pathway are closely associated with survival and prognosis in ESCC patients. A large number of studies have found that there are many molecules in ESCC that can regulate the PI3K/Akt/mTOR pathway. Overexpression of these molecules often causes aberrant activation of PI3K/Akt/mTOR pathway. Currently, several effective PI3K/Akt/mTOR pathway inhibitors have been developed, which can play anticancer roles either alone or in combination with other inhibitors. This review mainly introduces the general situation of ESCC, the composition and function of PI3K/Akt/mTOR pathway, and regulatory factors that interact with PI3K/Akt/mTOR signaling pathway. Meanwhile, mutations and inhibitors of PI3K/Akt/mTOR pathway in ESCC are also elucidated.

SNAIL1: Linking Tumor Metastasis to Immune Evasion

The transcription factor Snail1, a key inducer of epithelial-mesenchymal transition (EMT), plays a critical role in tumor metastasis. Its stability is strictly controlled by multiple intracellular signal transduction pathways and the ubiquitin-proteasome system (UPS). Increasing evidence indicates that methylation and acetylation of Snail1 also affects tumor metastasis. More importantly, Snail1 is involved in tumor immunosuppression by inducing chemokines and immunosuppressive cells into the tumor microenvironment (TME). In addition, some immune checkpoints potentiate Snail1 expression, such as programmed death ligand 1 (PD-L1) and T cell immunoglobulin 3 (TIM-3). This mini review highlights the pathways and molecules involved in maintenance of Snail1 level and the significance of Snail1 in tumor immune evasion. Due to the crucial role of EMT in tumor metastasis and tumor immunosuppression, comprehensive understanding of Snail1 function may contribute to the development of novel therapeutics for cancer.

Role of immune escape in different digestive tumours

A counterbalance between immune cells and tumour cells is key to fighting tumours, and immune escape is an important mechanism for the survival of tumour cells in the body. Tumor cells and their cytokines impair the activity of T cells, NK cells, macrophages and other immune cells through various ways, and change the expression of their own surface antigens so as to avoid the clearance of the immune system. Changes in major histocompatibility complex molecules, high expression of programmed death-ligand 1, and the presence of immunosuppressive cells in the tumor microenvironment (TME) are main means by which tumors impair the function of immune cells. During the development of tumours of the digestive system, different mechanisms acting on tumour cells, the TME, and immune cells lead to immune escape and promote tumour progression. In this paper, the mechanisms of immune escape in tumour cells of the digestive system are reviewed to provide a theoretical basis for the immunotherapy of gastrointestinal tumours.

The Functionalities and Clinical Significance of Tumor-Infiltrating Immune Cells in Esophageal Squamous Cell Carcinoma

Tumor-infiltrating immune cells have been implicated in the tumorigenesis and progression of esophageal squamous cell carcinoma (ESCC). However, the functionalities and clinical significance of immune cells remain largely unveiled. In this study, the gene expression data from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were extracted. The relative infiltrating levels were estimated by single-sample gene set enrichment analysis. Some cytotoxic immune cells were attenuated, and resting cytotoxic immune cells were accumulated in ESCC. Remarkably, we also observed that infiltrating levels of macrophage M2 and resting natural killer (NK) cells were increased in nonresponders of CRT, and T cells that had anticancer activities such as activated memory CD4 and T helper 2 (Th2) cells were significantly reduced in ESCC tissues of the nonresponders. Moreover, the high infiltrations of the resting natural killer (NK) and dendritic cell (DC) were observed to result in a shorter overall survival in ESCC. Consistently, high expression of immune checkpoint genes, CTLA4 and HAVCR2, was associated with poor prognosis. Furthermore, STAT5B, a key transcription factor, as well as its target genes, involved in the regulation of T cells, was significantly downregulated in ESCC, especially subgroup I, indicating that downregulation of STAT5B might be associated with reduced T cell-mediated anticancer activity. In conclusion, the present study significantly improved our understanding of the regulatory roles of immune cells in ESCC.

Targeted Immunotherapies in Gastrointestinal Cancer: From Molecular Mechanisms to Implications

Gastrointestinal cancer is a leading cause of cancer-related mortality and remains a major challenge for cancer treatment. Despite the combined administration of modern surgical techniques and chemoradiotherapy (CRT), the overall 5-year survival rate of gastrointestinal cancer patients in advanced stage disease is less than 15%, due to rapid disease progression, metastasis, and CRT resistance. A better understanding of the mechanisms underlying cancer progression and optimized treatment strategies for gastrointestinal cancer are urgently needed. With increasing evidence highlighting the protective role of immune responses in cancer initiation and progression, immunotherapy has become a hot research topic in the integrative management of gastrointestinal cancer. Here, an overview of the molecular understanding of colorectal cancer, esophageal cancer and gastric cancer is provided. Subsequently, recently developed immunotherapy strategies, including immune checkpoint inhibitors, chimeric antigen receptor T cell therapies, tumor vaccines and therapies targeting other immune cells, have been described. Finally, the underlying mechanisms, fundamental research and clinical trials of each agent are discussed. Overall, this review summarizes recent advances and future directions for immunotherapy for patients with gastrointestinal malignancies.

Correlation between the immune checkpoints and EMT genes proposes potential prognostic and therapeutic targets in ESCC

PD-1, PD-L1, CTLA-4, TIM-3, and LAG-3, crucial immune checkpoint molecules in the tumor microenvironment, identify as key targets for cancer immunotherapy. There is a correlation between immune cells and epithelial-mesenchymal transition (EMT)-related genes expression in varies human cancers. In this study, we aimed to investigate the probable association between expression of immune checkpoints and EMT in esophageal squamous cell carcinoma (ESCC) with clinical treats for providing the new therapeutic targets and prognostic value for the disease. Quantitative real-time PCR was used to investigate the gene expression profile of immune checkpoints (PD-1, PD-L1, CTLA-4, TIM-3, and LAG-3) and EMT (TWIST1 and MMP-13) genes based on the mRNA expression levels in 51 ESCC tissues. The upregulation of CTLA-4, PD-1, PD-L1, TIM-3, LAG-3, MMP-13, and TWIST1 were observed in 31.37%, 29.41%, 21.56%, 39.21%, 25.49%, 60.78%, and 56.86% of ESCC cases at the mRNA level, respectively. Dysregulation of immune checkpoints was related to lymph node involvement, stage of tumor progression, and depth of tumor invasion (P < 0.05). While overexpression of MMP-13 and TWIST1 was associated with lymph node involvement, stage of tumor progression, and grade of tumor differentiation (P < 0.05). The mRNA expression of immune checkpoint genes was significantly correlated to each other's (P = 0.000). Of importance, the data explored the significant association between the concomitant expression of immune checkpoints and EMT-related genes with each other in a variety of clinicopathological traits (P < 0.05). Consequently, immune checkpoints were positively correlated with EMT status in ESCC. The correlation between tumor immune microenvironment with the elevation of multiple immune checkpoints and EMT status may help to identify potential biomarkers for the simultaneous clinical use of multiple immune checkpoints blockade and other immunotherapies approaches for advanced ESCC patients.

Depleting Tumor Cells Expressing Immune Checkpoint Ligands-A New Approach to Combat Cancer

Antibodies against inhibitory immune checkpoint molecules (ICPMs), referred to as immune checkpoint inhibitors (ICIs), have gained a prominent place in cancer therapy. Several ICIs in clinical use have been engineered to be devoid of effector functions because of the fear that ICIs with preserved effector functions could deplete immune cells, thereby curtailing antitumor immune responses. ICPM ligands (ICPMLs), however, are often overexpressed on a sizeable fraction of tumor cells of many tumor types and these tumor cells display an aggressive phenotype with changes typical of tumor cells undergoing an epithelial-mesenchymal transition. Moreover, immune cells expressing ICPMLs are often endowed with immunosuppressive or immune-deviated functionalities. Taken together, these observations suggest that compounds with the potential of depleting cells expressing ICPMLs may become useful tools for tumor therapy. In this article, we summarize the current state of the art of these compounds, including avelumab, which is the only ICI targeting an ICPML with preserved effector functions that has gained approval so far. We also discuss approaches allowing to obtain compounds with enhanced tumor cell-depleting potential compared to native antibodies. Eventually, we propose treatment protocols that may be applied in order to optimize the therapeutic efficacy of compounds that deplete cells expressing ICPMLs.

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.

Acute Conditioning of Antigen-Expanded CD8+ T Cells via the GSK3β-mTORC Axis Differentially Dictates Their Immediate and Distal Responses after Antigen Rechallenge

Simple Summary

Expanded, antigen-experienced CD8⁺ T cells are utilized in immunotherapy to treat infections and cancers. Antigen rechallenge of these cells leads to their re-expansion. The effector functions of re-expanded CD8⁺ T cells are critical for their therapeutic efficacy. We found that acute conditioning of the cells, before antigen rechallenge, impacts their effector function after re-expansion. Our data showed that acute pharmacological modulation of the GSK3β-mTORC axis with TWS119 or rapamycin, but not Torin1, before antigen rechallenge promotes the effector functions of re-expanded CD8⁺ T cells. These findings suggest that acute conditioning of the GSK3β-mTORC axis in expanded CD8⁺ T cells, before antigen rechallenge, can promote the therapeutic performance of re-expanded CD8⁺ T cells.

Abstract

CD8⁺ T cells protect against tumors and intracellular pathogens. The inflammatory cytokines IL-2, IL-15, and IL-7 are necessary for their expansion. However, elevated serum levels of these cytokines are often associated with cancer, poorer prognosis of cancer patients, and exhaustion of antigen-expanded CD8⁺ T cells. The impact of acute conditioning of antigen-expanded CD8⁺ T cells with these cytokines is unknown. Here, we generated antigen-expanded CD8⁺ T cells using dendritic cells and PC-3 cells. The cells were acutely (18–24 h) conditioned with IL-2 and either the GSK3β inhibitor TWS119, the mTORC1 inhibitor rapamycin, or the mTORC1/2 inhibitor Torin1, then their immediate and post-re-expansion (distal) cytokine responses after antigen rechallenge were evaluated. We found that acute IL-2 conditioning upregulated the immediate antigen-induced cytokine response of the tested cells. Following their re-expansion, however, the cells showed a decreased cytokine response. These IL-2 conditioning-mediated impacts were counteracted with TWS119 or rapamycin but not with Torin1. Our data revealed that the acute conditioning of antigen-expanded CD8⁺ T cells with IL-2 modulates the GSK3β-mTORC signaling axis. This modulation differentially affected the immediate and distal cytokine responses of the cells. The acute targeting of this signaling axis could, therefore, represent a novel strategy for the modulation of antigen-expanded CD8⁺ T cells.

Varied functions of immune checkpoints during cancer metastasis

Immune checkpoints comprise diverse receptors and ligands including costimulatory and inhibitory molecules, which play monumental roles in regulating the immune system. Immune checkpoints retain key potentials in maintaining the immune system homeostasis and hindering the malignancy development and autoimmunity. The expression of inhibitory immune checkpoints delineates an increase in a plethora of metastatic tumors and the inhibition of these immune checkpoints can be followed by promising results. On the other hand, the stimulation of costimulatory immune checkpoints can restrain the metastasis originating from diverse tumors. From the review above, key findings emerged regarding potential functions of inhibitory and costimulatory immune checkpoints targeting the metastatic cascade and point towards novel potential Achilles’ heels of cancer that might be exploited therapeutically in the future.

Prognostic Values of TIM-3 Expression in Patients With Solid Tumors: A Meta-Analysis and Database Evaluation

Background: T cell immunoglobulin and mucin-domain containing molecule-3 (TIM-3), a novel emerging immune checkpoint molecule, was reported to express both on various kinds of immune cells and tumor cells. Many previous studies have investigated the prognostic significance of TIM-3 in cancer. However, the sample number from single study was limited and results remained controversial.

Methods: We searched PubMed, Web of Science, and Embase databases for publications concerning TIM-3 expression in solid cancers up to March 2020. The correlations between TIM-3 and survival as well as clinical-pathological features were analyzed. Pooled hazard ratios (HRs), odds ratios (ORs), and 95% confidence interval (CI) were estimated by either fixed or random effects models.

Results: A total of 3,072 patients were included in our meta-analysis. The result suggested that TIM-3 protein overexpression was relevant to poor overall survival (HR = 1.73, 95% CI = 1.39–2.15, P < 0.001). Moreover, TIM-3 was shown to be connected with lymph node metastasis (N+ vs. N-, OR = 1.59, 95% CI = 1.10–2.29, P = 0.013), tumor grade (G2-3 vs. G1, OR = 1.68, 95% CI = 1.21–2.34, P = 0.002), as well as PD-1 expression (PD-1^high vs. PD-1^low, OR = 3.26, 95% CI = 2.20–4.82, P < 0.001). In database test, significant correlations between high TIM-3 mRNA expression and poor overall survival for patients with non-small cell lung cancer and gastric cancer were observed (HR = 1.46, 95% CI = 1.23–1.72, P < 0.001; HR = 1.41, 95% CI = 1.12–1.77, P = 0.0038).

Conclusion: Our meta-analysis highlights that TIM-3 has the potential to serve as a prognostic marker and a valuable therapeutic target in solid tumors.

Prognostic Impact of PD-1 and Tim-3 Expression in Tumor Tissue in Stage I-III Colorectal Cancer

Background

Programmed cell death receptor 1 (PD-1) and T cell immunoglobulin mucin-3 (Tim-3) are considered as important immunosuppressive molecules and play an important role in tumor immune escape and cancer progression. However, it remains unclear whether PD-1 and Tim-3 are coexpressed in stage I-III colorectal cancer (CRC) and how they impact on the prognosis of the disease.

Materials and Methods

A total of two cohorts with 451 patients who underwent surgery for stage I-III CRC treatment were enrolled in the study. Among which, 378 cases were from The Cancer Genome Atlas (TCGA) database and 73 cases were from the Fourth Hospital of Hebei Medical University (FHHMU) cohort. The mRNA expressions of PD-1 and Tim-3 in tumor tissue in stage I-III CRC were obtained from TCGA database. Immunohistochemistry was used to assess the expressions of PD-1 and Tim-3 in tumor tissue in stage I-III CRC in the FHHMU cohort. Interactive relationships between PD-1 and Tim-3 were retrieved through the online STRING database, which was used to study the interactions between proteins. DAVID, consisting of comprehensive biological function annotation information, was applied for the GO and KEGG pathway enrichment analysis of the interactive genes.

Results

In the FHHMU cohort, the high expressions of PD-1 and Tim-3 were, respectively, found in 42.47% and 84.93% of stage I-III CRC tissue. PD-1 was significantly associated with age, primary site, and lymphatic metastasis. Tim-3 was closely related to the primary site. Correlation analysis showed that PD-1 and Tim-3 were positively correlated (r = 0.5682, P < 0.001). In TCGA cohort, PD-1 and Tim-3 were associated with the prognosis of CRC patients in terms of 5-year survival (P < 0.05). In the FHHMU cohort, the 5-year survival of patients with high levels of PD-1 and Tim-3 was 54.84% and 65.85%, respectively. Among which, the high expression of PD-1 was associated with poor prognosis (5-year OS: 54.84% vs. 88.10%, P = 0.003). The 5-year survival rate of CRC patients with coexpression of PD-1 and Tim-3 was 45.00%, which was significantly worse than non-coexpression (72.73%, 85.71%, and 90.48% separately). The functional network of PD-1 and Tim-3 primarily participates in the regulation of immune cell activation and proliferation, immune cell receptor complex, cell adhesion molecules, and T cell receptor signaling pathway.

Conclusion

In summary, upregulation of PD-1 and Tim-3 in stage I-III CRC tumor tissue could be associated with the poor prognosis of patients. Those patients with coexpression of PD-1 and Tim-3 may have a significantly worse prognosis.

TIM-3 Participates in the Invasion and Metastasis of Nasopharyngeal Carcinoma via SMAD7/SMAD2/SNAIL1 Axis-Mediated Epithelial-Mesenchymal Transition

Background

T-cell immunoglobulin and mucin domain-containing molecule-3 (TIM-3) was originally found to negatively regulate immune response and mediate immune escape in tumors. Subsequently, an increasing body of evidence has shown that TIM-3 exerts positive functions in the development and progression of several tumors. However, the role of TIM-3 in nasopharyngeal carcinoma (NPC) remains unknown.

Methods

Data from the Cancer Genome Atlas-head and neck squamous cell carcinoma and immunohistochemistry were analyzed to compare the expression of TIM-3 in NPC and non-cancerous nasopharyngitis tissues. Cell proliferation was evaluated using the Cell counting kit-8 in vitro and xenograft experiment in nude mice in vivo. Flow cytometry was used to evaluate the cell cycle. The migration and invasion of NPC cells were assessed through wound healing and Transwell assays. In addition, Western blotting was used to analyze the expression of specific proteins.

Results

Higher expression of TIM-3 was detected in NPC tissues than normal nasopharyngeal tissues and positively correlated with the clinical stage and T classification; however, it was not correlated with gender, age, and N classification. Furthermore, overexpression of TIM-3 using lentiviral vectors increased the malignancy of 6-10B and CNE-2 cell lines that lowly express TIM-3, by promoting cell proliferation, migration, and invasion in vitro and in vivo. In addition, overexpression of TIM-3 was associated with upregulation of matrix metalloproteinase 9 (MMP9) and MMP2, and led to epithelial-mesenchymal transition (EMT) by increasing the levels of mesenchymal markers (ie, N-cadherin, Vimentin) and decreasing those of the epithelial marker E-cadherin. Further study showed that SMAD7 was downregulated in the TIM-3 overexpression group. Relatively, phosphorylated SMAD2 and downstream molecule SNAIL1 were also upregulated in this group.

Conclusion

TIM-3 exerts a tumor-promoting function in NPC by mediating changes in the SMAD7/SMAD2/SNAIL1 axis. These findings provide a new idea for the study of invasion, metastasis, and treatment of NPC.

IL-6 promotes metastasis of non-small-cell lung cancer by up-regulating TIM-4 via NF-κB

OBJECTIVES

Interleukin-6 (IL-6) is critical for the development of non-small-cell lung cancer (NSCLC). Recently, we identified T-cell immunoglobulin domain and mucin domain 4 (TIM-4) as a new pro-growth player in NSCLC progression. However, the role of TIM-4 in IL-6-promoted NSCLC migration, invasion and epithelial-to-mesenchymal transition (EMT) remains unclear.

MATERIALS AND METHODS

Expressions of TIM-4 and IL-6 were both evaluated by immunohistochemical staining in NSCLC tissues. Real-time quantitative PCR (qPCR), Western blot, flow cytometry and RT-PCR were performed to detect TIM-4 expression in NSCLC cells with IL-6 stimulation. The roles of TIM-4 in IL-6 promoting migration and invasion of NSCLC were detected by transwell assay. EMT-related markers were analysed by qPCR and Western blot in vitro, and metastasis was evaluated in BALB/c nude mice using lung cancer metastasis mouse model in vivo.

RESULTS

High IL-6 expression was identified as an independent predictive factor for TIM-4 expression in NSCLC tissues. NSCLC patients with TIM-4 and IL-6 double high expression showed the worst prognosis. IL-6 promoted TIM-4 expression in NSCLC cells depending on NF-κB signal pathway. Both TIM-4 and IL-6 promoted migration, invasion and EMT of NSCLC cells. Interestingly, TIM-4 knockdown reversed the role of IL-6 in NSCLC and IL-6 promoted metastasis of NSCLC by up-regulating TIM-4 via NF-κB.

CONCLUSIONS

TIM-4 involves in IL-6 promoted migration, invasion and EMT of NSCLC.

Significance of TIM-3 Expression in Resected Esophageal Squamous Cell Carcinoma

BACKGROUND

T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) is a promising checkpoint. However, its features and prognostic value remain undetermined in esophageal squamous cell carcinoma (ESCC). This study evaluated the prognostic value of TIM-3 expression and its relationship with programmed cell death 1 (PD-1) and CD8⁺ tumor-infiltrating lymphocytes (TILs) in patients with surgically resected ESCC.

METHODS

Expression levels of TIM-3, PD-1, and CD8⁺ TILs in ESCC were determined by immunohistochemistry. The association between clinicopathologic features or clinical outcomes and TIM-3 expression was analyzed.

RESULTS

A total of 183 patients with ESCC who had undergone esophagectomy without implementation of neoadjuvant therapy at the Second Affiliated Hospital of Soochow University in Suzhou, China from January 2009 to December 2014 were included. PD-1 positivity (P = .032) and high CD8⁺ TIL density (P = .035) significantly correlated with positive TIM-3 expression. TIM-3 positivity was an independent risk factor for recurrence-free survival (RFS) (P < .001) and overall survival (OS) (P < .001). Subgroup analysis revealed that the TIM-3⁺PD-1⁺CD8 low group had the worst RFS and OS, whereas the TIM-3^-PD-1^-CD8 high group had the best RFS and OS (RFS: log-rank test P < .001; OS: log-rank test P < .001).

CONCLUSIONS

Positive TIM-3 expression was associated with PD-1 positivity and high CD8⁺ TIL density and was an independent risk factor for RFS and OS in ESCC. Furthermore, the combination of TIM-3 and PD-1 expression or CD8⁺ TIL density could further stratify patients into different groups with distinct prognosis.

Functions of Immune Checkpoint Molecules Beyond Immune Evasion

Immune checkpoint molecules, including inhibitory and stimulatory immune checkpoint molecules, are defined as ligand-receptor pairs that exert inhibitory or stimulatory effects on immune responses. Most of the immune checkpoint molecules that have been described so far are expressed on cells of the adaptive immune system, particularly on T cells, and of the innate immune system. They are crucial for maintaining the self-tolerance and modulating the length and magnitude of immune responses of effectors in different tissues to minimize the tissue damage. More and more evidences have shown that inhibitory or stimulatory immune checkpoint molecules are expressed on a sizeable fraction of tumor types. Although the main function of tumor cell-associated immune checkpoint molecules is considered to mediate the immune evasion, it has been reported that the immune checkpoint molecules expressed on tumor cells also play important roles in the maintenance of many malignant behaviors, including self-renewal, epithelial-mesenchymal transition, metastasis, drug resistance, anti-apoptosis, angiogenesis, or enhanced energy metabolisms. In this section, we mainly focus on delineating the roles of the tumor cell-associated immune checkpoint molecules beyond immune evasion, such as PD-L1, PD-1, B7-H3, B7-H4, LILRB1, LILRB2, TIM3, CD47, CD137, and CD70.

Characterization of LAG-3, CTLA-4, and CD8+ TIL density and their joint influence on the prognosis of patients with esophageal squamous cell carcinoma

Background

We aimed to characterize the relationships of lymphocyte activation gene-3 (LAG-3) expression, cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) expression, and CD8⁺ tumor-infiltrating lymphocyte (TIL) density, and to investigate the joint prognostic impact of these three markers in patients with surgically resected esophageal squamous cell carcinoma (ESCC).

Methods

Expression of LAG-3, CTLA-4 and the density of CD8⁺ TILs were evaluated by immunohistochemistry in resected ESCC. The associations between LAG-3 expression and clinicopathologic characteristics, as well as patient prognoses, were analyzed.

Results

A total of 183 patients were included. LAG-3 expression was observed in 69 (37.7%) patients. Positive LAG-3 expression was significantly associated with CTLA-4 expression (P=0.004). LAG-3 positivity, CTLA-4 positivity, and low CD8⁺ TIL densities were significantly associated with worsening recurrence-free survival (RFS) [LAG-3: hazard ratio (HR), 1.72; 95% confidence interval (CI), 1.10-2.89; P=0.019; CTLA-4: HR, 1.69; 95% CI, 1.04-2.73; P=0.033; CD8⁺: HR, 0.60; 95% CI, 0.38-0.94; P=0.025] and overall survival (OS) (LAG-3: HR, 2.09; 95% CI, 1.24-3.53; P=0.006; CTLA-4: HR, 1.47; 95% CI, 0.86-2.53; P=0.161; CD8⁺: HR, 0.56; 95% CI, 0.33-0.95; P=0.032). Subgroup analysis revealed that the LAG-3 CTLA-4 CD8⁺ group had the best RFS (P<0.001) and OS (P<0.001).

Conclusions

LAG-3 expression was correlated with CTLA-4 expression on TILs. Positive LAG-3 expression was associated with poor prognoses in ESCC. A combination of LAG-3, CTLA-4 expression and CD8⁺ TILs density could further stratify patients into different subgroups with distinct prognoses.

Jiedu Sangen Decoction Reverses Epithelial-to-mesenchymal Transition and Inhibits Invasion and Metastasis of Colon Cancer via AKT/GSK-3β Signaling Pathway

Ethnopharmacology relevance: Jiedu Sangen Decoction (JSD), an empirical prescription of Traditional Chinese Medicine (TCM), has been reported to inhibit invasion and metastasis of colon cancer in our previous study. The aim of this study was to investigate the mechanism of JSD-triggered inhibition of invasion and metastasis in colon cancer. Methods: In vitro, AKT1 knockdown (si-AKT1) or overexpression (oe-AKT1) cells were successfully constructed both in SW480 and SW620 cell lines. Si-AKT1 and oe-AKT1 cells were then treated with or without JSD. Cell invasion, metastasis potential and expression of epithelial-mesenchymal transformation (EMT)-related and AKT1/GSK-3β proteins were then observed by wound healing, transwell, and western blot assays. In vivo, liver metastasis model mice were developed by inoculating SW480 cells. After JSD diet intervention, living fluorescence imaging and weight measurements were carried out to investigate JSD induced inhibition effects on liver metastasis of colon cancer. Immunohistochemistry and western blot assays were performed to observe tissue features and detect protein expression. Results: Invasion and metastasis potential, as well as EMT of colon cancer, can be markedly inhibited by JSD treatment or AKT1 knockdown, while enhanced by AKT1 overexpression. JSD-induced inhibition effects were significantly weakened when AKT1 was knocked down, while clearly enhanced when AKT1 was overexpressed. Additionally, JSD could lead to an increase in expression of E-cadherin, and a decrease in expression of N-cadherin, Vimentin, p-AKT1, AKT1, p- GSK-3β, Snail, Slug, and Twist in colon cancer cells. Conclusion: JSD reverses EMT and inhibits invasion and metastasis of colon cancer through the AKT/GSK-3β signaling pathway.

Cancer immunotherapy using anti-TIM3/PD-1 bispecific antibody: a patent evaluation of EP3356411A1

Introduction: TIM3 and PD-1 are checkpoint inhibitors in cancer that coordinate the downregulation of the proliferation of antigen-specific lymphocytes. There is a great need to discover and develop new therapies focused on inhibiting the action of TIM3 and PD-1 and consequently improving the immune response in the various types of cancer. The authors of patent EP3356411A1 propose several anti-TIM3/anti-PD-1 bispecific antibodies, as well as the method for producing them and their pharmacological application in the treatment of cancer. Areas covered: Patent EP3356411A1 describes a method by producing anti-TIM3/anti-PD-1 bispecific antibodies and their potential in cancer treatment. Expert opinion: Data supporting the patent demonstrate the ability by producing anti-TIM3/anti-PD-1 bispecific antibodies. Although the proposed methodology is very interesting and promising, further studies are necessary to assess the clinical applicability of the inventions on cancer.

The Vicious Cross-Talk between Tumor Cells with an EMT Phenotype and Cells of the Immune System

Carcinoma cells that undergo an epithelial-mesenchymal transition (EMT) and display a predominantly mesenchymal phenotype (hereafter EMT tumor cells) are associated with immune exclusion and immune deviation in the tumor microenvironment (TME). A large body of evidence has shown that EMT tumor cells and immune cells can reciprocally influence each other, with EMT cells promoting immune exclusion and deviation and immune cells promoting, under certain circumstances, the induction of EMT in tumor cells. This cross-talk between EMT tumor cells and immune cells can occur both between EMT tumor cells and cells of either the native or adaptive immune system. In this article, we review this evidence and the functional consequences of it. We also discuss some recent evidence showing that tumor cells and cells of the immune system respond to similar stimuli, activate the expression of partially overlapping gene sets, and acquire, at least in part, identical functionalities such as migration and invasion. The possible significance of these symmetrical changes in the cross-talk between EMT tumor cells and immune cells is addressed. Eventually, we also discuss possible therapeutic opportunities that may derive from disrupting this cross-talk.

Delphinidin inhibits epidermal growth factor-induced epithelial-to-mesenchymal transition in hepatocellular carcinoma cells

Epithelial-to-mesenchymal transition (EMT), important cellular process in metastasis of primary tumors, is characterized by loss of their cell polarity, disruption of cell-cell adhesion, and gain certain properties of mesenchymal phenotype that enable migration and invasion. Delphinidin is a member of anthocyanidin belong to flavonoid groups, known as having pharmacological and physiological effects including anti-tumorigenic, antioxidative, anti-inflammatory, and antiangiogenic effects. However, the effects of delphinidin on EMT is rarely investigated. Epidermal growth factor (EGF) is known as a crucial inducer of EMT in various cancer including hepatocellular carcinoma (HCC). To determine whether delphinidin inhibits EGF-induced EMT in HCC cells, antiproliferative effect of delphinidin on Huh7 and PLC/PRF/5 cells were measured by Cell Counting Kit-8 assay. As a result, delphinidin inhibited cell proliferation in a dose-dependent manner. Based on the result of proliferation, to measure the effects of delphinidin on EGF-induced EMT, we designated a proper concentration of delphinidin, which is not affected to cell proliferation. We found that delphinidin inhibits morphological changes from epithelial to mesenchymal phenotype by EGF. Moreover, delphinidin increased the messenger RNA and protein expression of E-cadherin and decreased those of Vimentin and Snail in EGF-induced HCC cells. Also, delphinidin prevented motility and invasiveness of EGF-induced HCC cells through suppressing activation of matrix metalloproteinase 2, EGF receptor (EGFR), AKT, and extracellular signal-regulated kinase (ERK). Taken together, our findings demonstrate that delphinidin inhibits EGF-induced EMT by inhibiting EGFR/AKT/ERK signaling pathway in HCC cells.

Aberrant methylation of EYA4 promotes epithelial-mesenchymal transition in esophageal squamous cell carcinoma

EYA4, one of the four members of the EYA gene family, is associated with several human cancers. However, its biological functions and molecular mechanisms in the progression of cancer, particularly in esophageal squamous cell carcinoma (ESCC), remain unknown. In the present study, we found that EYA4 was underexpressed and hypermethylated in most of the ESCC cell lines tested (85.7%, 6/7). Treatment with 5‐aza‐dC and/or trichostatin A (TSA) restored EYA4 expression in ESCC cell lines, which indicates that EYA4 expression was epigenetically regulated. Similarly, EYA4 was aberrantly hypermethylated in ESCC tissues (78%, 39/50) and downregulation of EYA4 occurred in approximately 65% of primary ESCC at protein level where it was associated significantly with TNM stage and lymph node metastases. Knockdown of EYA4 in KYSE30 and KYSE70 ESCC cells using small hairpin RNA increased migration and invasive motility in vitro. Conversely, the overexpression of EYA4 in KYSE180 and KYSE450 promoted an epithelial phenotype, which consisted of decreased migration and invasion abilities and a decrease in TGF‐β1‐induced epithelial‐mesenchymal transition. Mechanistically, EYA4 overexpression reduced the phosphorylation of Akt and glycogen synthase kinase (GSK) 3β, which led to the inactivation of slug. In addition, we found that TGF‐β1 decreased EYA4 expression in both a dose‐dependent and a time‐dependent manner in KYSE30 cells, accompanied by an increase in the expression of DNA methyltransferases, especially DNMT3A. In summary, EYA4 is frequently hypermethylated in ESCC and may function as a tumor suppressor gene in the development of ESCC.

Down-regulation of long non-coding RNA ESCCAL_1 inhibits tumor growth of esophageal squamous cell carcinoma in a xenograft mouse model

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal malignant cancers with high incidence and mortality. Current reliable effective diagnostic and prognostic biomarkers are very limited in clinic. Emerging evidence indicates that dysregulated expression of the long non-coding RNAs (lncRNAs) was examined in various types of cancer including ESCC. ESCC associated lncRNA _1 (ESCCAL_1) was first time identified to be increased expression in ESCC, and therefore named by our research team. However, its potential function in the progression of ESCC remains unclear. In this study, we investigated the effect of ESCCAL_1 knockdown on ESCC tumorigenicity using a xenograft mouse model and explored the underlying molecular mechanism. Here we showed that ESCCAL_1 knockdown significantly inhibited EC9706 cell growth in nude mice. Interestingly, we also found that reduced expression of ESCCAL_1 resulted in distinct alterations of relative phosphorylation level of kinases (p-p38α, p-JNK, p-FAK and p-Src), and significant changes of the expression level of apoptosis-related proteins (p53, BAX, Bcl-2 and Caspase-3). In summary, our results suggest that lncRNA ESCCAL_1 is a potential diagnostic and prognostic target of ESCC.

The tumor microenvironment: Thousand obstacles for effector T cells

The immune system is endowed with the capability to recognize and destroy transformed cells, but even in the presence of an immune infiltrate many tumors do progress. In the last decades new discoveries have shed light into (some of) the underlying mechanisms. Immune effector cells are not only under the influence of immune suppressive cell subsets, but also intrinsically regulated by immune check point molecules that under physiological condition avoid attach of healthy tissue. Moreover, tumor cells are modifying the surrounding microenvironment through secretion of immune modulators as well as via their own metabolism, thus further impairing the development of immune effector functions. Different approaches are currently being evaluated in the clinic to overcome those regulatory mechanisms and to unleash effector T cells.

Tumor cell-associated immune checkpoint molecules - Drivers of malignancy and stemness

Inhibitory or stimulatory immune checkpoint molecules are expressed on a sizeable fraction of tumor cells in different tumor types. It was thought that the main function of tumor cell-associated immune checkpoint molecules would be the modulation (down- or upregulation) of antitumor immune responses. In recent years, however, it has become clear that the expression of immune checkpoint molecules on tumor cells has important consequences on the biology of the tumor cells themselves. In particular, a causal relationship between the expression of these molecules and the acquisition of malignant traits has been demonstrated. Thus, immune checkpoint molecules have been shown to promote the epithelial-mesenchymal transition of tumor cells, the acquisition of tumor-initiating potential and resistance to apoptosis and antitumor drugs, as well as the propensity to disseminate and metastasize. Herein, we review this evidence, with a main focus on PD-L1, the most intensively investigated tumor cell-associated immune checkpoint molecule and for which most information is available. Then, we discuss more concisely other tumor cell-associated immune checkpoint molecules that have also been shown to induce the acquisition of malignant traits, such as PD-1, B7-H3, B7-H4, Tim-3, CD70, CD28, CD137, CD40 and CD47. Open questions in this field as well as some therapeutic approaches that can be derived from this knowledge, are also addressed.

T-cell immunoglobulin mucin-3 as a potential inducer of the epithelial-mesenchymal transition in hepatocellular carcinoma

T-cell immunoglobulin mucin (TIM)-3 is an important member of the TIM gene family, which was thought to contribute to the progression of numerous types of cancer, including hepatocellular carcinoma (HCC); however, the mechanism underlying TIM-3 functions in HCC progression has not yet been extensively investigated. The present study aimed to investigate the function of TIM-3 in the metastasis of HCC and to determine whether the alteration of TIM-3 expression levels regulated the epithelial-mesenchymal transition (EMT) occurrence of HCC, using epithelial (E)-cadherin, neuronal (N)-cadherin, matrix metallopeptidase-9 (MMP-9), Twist 1, Slug, Snail, and Smad as EMT biomarkers. The results demonstrated that upregulation of TIM-3 using TIM-3 lentiviral activation particles (5 µl) increased cell migration and invasion, which was decreased in TIM-3 short interfering RNA-infected cells (10 µM, 3 µl) correspondingly. SMMC-7721 HCC cells were used as the control. EMT was aggravated in TIM-3 upregulated SMMC-7721 cells, which was attenuated in the TIM-3 interference group, accompanied by an alteration of E-cadherin, N-cadherin, MMP-9, Twist 1, Slug, Snail and Smad expression levels. The data presented suggests that TIM-3 serves an essential role in the metastasis of HCC, the mechanism of which was associated with EMT occurrence. Interference of TIM-3 is expected to be an effective means to prevent and control EMT, and further the metastasis of HCC.

Low TIM3 expression indicates poor prognosis of metastatic prostate cancer and acts as an independent predictor of castration resistant status

T cell immunoglobulin 3 (TIM3) is a cell surface star molecule expressed on T cells, and also marks dysfunctional CD8⁺ T cells in various kinds of cancers. However, there are few studies focusing on the expression of TIM3 in tumor cells. In our study, we recruited 139 patients with metastatic prostate cancer (mPCa) who received transurethral resection of the prostate (TURP) consecutively to examine whether TIM3 expression level is associated with overall survival (OS) in mPCa patients. Immunohistochemistry was performed to determine TIM3 expression in prostate cancer tissues and then patients were divided into two groups. In multivariate Cox analysis, we revealed that mPCa patients with negative TIM3 expression, younger age, no radiotherapy, higher Gleason score, higher cT stage and patients of mCRPC had a shorter OS. Therefore, a predictive nomogram was generated with identified independent prognostic factors to assess patients’ OS at 3 years. Multivariate logistic regression revealed that higher cT stage, higher Gleason score and low TIM3 expression were independent predictors of metastatic castration resistant prostate cancer (mCRPC). In conclusion, low expression level of TIM3 in prostate cancer tissues is an independent prognostic factor of poor prognosis for mPCa patients, and also an independent predictor of mCRPC.