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

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.

Identification of EMT-associated prognostic features among grade II/III gliomas

Grade II/III gliomas have a highly heterogeneous clinical course. Identifying prognostic biomarkers in grade II/III gliomas is essential to guide clinical management. We explored epithelial-mesenchymal transition (EMT)-related genes to uncover prognostic features in grade II/III gliomas. Consensus cluster analysis of 200 EMT-related genes classified 512 grade II/III glioma samples into two molecular subtypes, C1 and C2. The C1 subtype had significantly worse overall survival compared to the C2 subtype. Pathway analysis revealed C1 tumors were highly associated with tumor progression pathways and demonstrated higher immune cell infiltration scores. Differential expression analysis identified four genes (ACTN1, AQP1, LAMC3, NRM) that discriminated the two subtypes. Validation in external datasets confirmed that high expression of this four-gene signature predicted poor prognosis in grade II/III gliomas. Cellular experiments showed ACTN1, AQP1 and NRM promoted glioma cell proliferation, migration and invasion. We examined correlations of the signature genes with T cell exhaustion markers and found ACTN1 expression had the strongest association. Immunohistochemistry analysis further demonstrated that ACTN1 protein expression in grade II/III gliomas was negatively correlated with patient overall survival. In summary, our study identified a concise four-gene signature that robustly predicts grade II/III gliomas prognosis across multiple datasets. The signature provides clinical relevance in distinguishing more aggressive grade II/III glioma tumors. Targeting the ACTN1, AQP1 and NRM genes may offer new therapeutic opportunities to improve grade II/III gliomas patient outcomes.

Corynoline inhibits esophageal squamous cell carcinoma growth via targeting Pim-3

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is an aggressive and deadly malignancy characterized by late-stage diagnosis, therapy resistance, and a poor 5-year survival rate. Finding novel therapeutic targets and their inhibitors for ESCC prevention and therapy is urgently needed.

METHODS

We investigated the proviral integration site for maloney murine leukemia virus 3 (Pim-3) protein levels using immunohistochemistry. Using Methyl Thiazolyl Tetrazolium and clone formation assay, we verified the function of Pim-3 in cell proliferation. The binding and inhibition of Pim-3 by corynoline were verified by computer docking, pull-down assay, cellular thermal shift assay, and kinase assay. Cell proliferation, Western blot, and a patient-derived xenograft tumor model were performed to elucidate the mechanism of corynoline inhibiting ESCC growth.

RESULTS

Pim-3 was highly expressed in ESCC and played an oncogenic role. The augmentation of Pim-3 enhanced cell proliferation and tumor development by phosphorylating mitogen-activated protein kinase 1 (MAPK1) at T185 and Y187. The deletion of Pim-3 induced apoptosis with upregulated cleaved caspase-9 and lower Bcl2 associated agonist of cell death (BAD) phosphorylation at S112. Additionally, binding assays demonstrated corynoline directly bound with Pim-3, inhibiting its activity, and suppressing ESCC growth.

CONCLUSIONS

Our findings suggest that Pim-3 promotes ESCC progression. Corynoline inhibits ESCC progression through targeting Pim-3.

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.

Preclinical tumor mouse models for studying esophageal cancer

Preclinical models are extensively employed in cancer research because they can be manipulated in terms of their environment, genome, molecular biology, organ systems, and physical activity to mimic human behavior and conditions. The progress made in in vivo cancer research has resulted in significant advancements, enabling the creation of spontaneous, metastatic, and humanized mouse models. Most recently, the remarkable and extensive developments in genetic engineering, particularly the utilization of CRISPR/Cas9, transposable elements, epigenome modifications, and liquid biopsies, have further facilitated the design and development of numerous mouse models for studying cancer. In this review, we have elucidated the production and usage of current mouse models, such as xenografts, chemical-induced models, and genetically engineered mouse models (GEMMs), for studying esophageal cancer. Additionally, we have briefly discussed various gene-editing tools that could potentially be employed in the future to create mouse models specifically for esophageal cancer research.

Characterization of antigen-specific CD8+ memory T cell subsets in peripheral blood of patients with multiple sclerosis

Background

Increasing evidence indicates the importance of CD8⁺ T cells in autoimmune attack against CNS myelin and axon in multiple sclerosis (MS). Previous research has also discovered that myelin-reactive T cells have memory phenotype functions in MS patients. However, limited evidence is available regarding the role of CD8⁺ memory T cell subsets in MS. This study aimed to explore potential antigen-specific memory T cell-related biomarkers and their association with disease activity.

Methods

The myelin oligodendrocyte glycoprotein (MOG)-specific CD8⁺ memory T cell subsets and their related cytokines (perforin, granzyme B, interferon (IFN)-γ) and negative co-stimulatory molecules (programmed cell death protein 1 (PD-1), T- cell Ig and mucin domain 3 (Tim-3)) were analyzed by flow cytometry and real-time PCR in peripheral blood of patients with relapsing-remitting MS.

Results

We found that MS patients had elevated frequency of MOG-specific CD8⁺ T cells, MOG-specific central memory T cells (T_CM), MOG-specific CD8⁺ effector memory T cells (T_EM), and MOG-specific CD8⁺ terminally differentiated cells (T_EMRA); elevated granzyme B expression on MOG-specific CD8⁺ T_CM; and, on MOG-specific CD8⁺ T_EM, elevated granzyme B and reduced PD-1 expression. The Expanded Disability Status Scale score (EDSS) in MS patients was correlated with the frequency of MOG-specific CD8⁺ T_CM, granzyme B expression in CD8⁺ T_CM, and granzyme B and perforin expression on CD8⁺ T_EM, but with reduced PD-1 expression on CD8⁺ T_EM.

Conclusion

The dysregulation of antigen-specific CD8⁺ memory T cell subsets, along with the abnormal expression of their related cytokines and negative co-stimulatory molecules, may reflect an excessive or persistent inflammatory response induced during early stages of the illness. Our findings strongly suggest positive regulatory roles for memory T cell populations in MS pathogenesis, probably via molecular mimicry to trigger or promote abnormal peripheral immune responses. Furthermore, downregulated PD-1 expression may stimulate a positive feedback effect, promoting MS-related inflammatory responses via the interaction of PD-1 ligands. Therefore, these parameters are potential serological biomarkers for predicting disease development in MS.

Tumor cell plasticity in targeted therapy-induced resistance: mechanisms and new strategies

Despite the success of targeted therapies in cancer treatment, therapy-induced resistance remains a major obstacle to a complete cure. Tumor cells evade treatments and relapse via phenotypic switching driven by intrinsic or induced cell plasticity. Several reversible mechanisms have been proposed to circumvent tumor cell plasticity, including epigenetic modifications, regulation of transcription factors, activation or suppression of key signaling pathways, as well as modification of the tumor environment. Epithelial-to-mesenchymal transition, tumor cell and cancer stem cell formation also serve as roads towards tumor cell plasticity. Corresponding treatment strategies have recently been developed that either target plasticity-related mechanisms or employ combination treatments. In this review, we delineate the formation of tumor cell plasticity and its manipulation of tumor evasion from targeted therapy. We discuss the non-genetic mechanisms of targeted drug-induced tumor cell plasticity in various types of tumors and provide insights into the contribution of tumor cell plasticity to acquired drug resistance. New therapeutic strategies such as inhibition or reversal of tumor cell plasticity are also presented. We also discuss the multitude of clinical trials that are ongoing worldwide with the intention of improving clinical outcomes. These advances provide a direction for developing novel therapeutic strategies and combination therapy regimens that target tumor cell plasticity.

Regulation of epithelial-mesenchymal transition by tumor microenvironmental signals and its implication in cancer therapeutics

Epithelial-mesenchymal transition (EMT) has been implicated in various aspects of tumor development, including tumor invasion and metastasis, cancer stemness, and therapy resistance. Diverse stroma cell types along with biochemical and biophysical factors in the tumor microenvironment impinge on the EMT program to impact tumor progression. Here we provide an in-depth review of various tumor microenvironmental signals that regulate EMT in cancer. We discuss the molecular mechanisms underlying the role of EMT in therapy resistance and highlight new therapeutic approaches targeting the tumor microenvironment to impact EMT and tumor progression.

The expression of long non-coding RNA LINC01389, LINC00365, RP11-138J23.1, and RP11-354K4.2 in gastric cancer and their impacts on EMT

BACKGROUND

Epithelial cancers acquire the epithelial to mesenchymal transition (EMT), which leads tumor cells to invade and metastasize to adjacent and distant tissues. The mechanisms involved in EMT phenotype are controlled by numerous markers as well as signalling pathways. Recently, long non-coding RNAs (lncRNAs) were introduced that play the regulatory role in EMT via crosstalk with EMT-related transcription factors and signalling pathways. The present study aimed to investigate the expression of four lncRNAs in human GC and elucidate their probable role in EMT procedure and the pathogenesis of gastric cancer (GC).

METHODS

The expression profile of lncRNAs (LINC01389, LINC00365, RP11-138J23.1, and RP11-354K4.2) and mRNAs (TWIST1, MMP13, MAML1, CD44s, and SALL4) between eighty-three GC and adjacent non-cancerous tissues were assessed by quantitative real-time PCR.

RESULTS

The significant downregulation of LINC00365 (66.3%) and RP11-354K4.2 (62.7%) were observed in GC samples; while the upregulation of LINC01389, RP11-138J23.1, TWIST1, MMP13, MAML1, CD44s, and SALL4 were found in 67.5%, 45.8%, 56.6%, 44.6%, 59%, 55.4%, and 62.7% tumors samples at the mRNA level, respectively. Dysregulation of these lncRNAs and EMT-related markers was significantly related to each other in a variety of clinicopathological features of patients (P < 0.05), indicating positive correlations between LINC01389, LINC00365, RP11-138J23.1, and RP11-354K4.2 with EMT status in GC.

CONCLUSION

These EMT-regulating lncRNAs may play a key role in transforming gastric epithelial to mesenchymal phenotype and can be novel therapeutic targets for GC. Our results highlight the importance of discovering new lncRNAs involved in gastric carcinogenesis. Detailed molecular mechanisms of these noncoding-coding markers in GC are urgently required.

Feasibility and Safety of Anlotinib Monotherapy for Patients with Previously Treated Advanced Esophageal Squamous Cell Carcinoma: A Real-World Exploratory Study

Objective

This study was to investigate the feasibility and safety of anlotinib monotherapy for patients with advanced or metastatic esophageal squamous cell carcinoma (ESCC) retrospectively.

Methods

This study was designed as a real-world study. A total of 83 patients with advanced or metastatic ESCC who received anlotinib monotherapy were included. Demographic characteristics of the patients, efficacy data of the treatment and adverse reactions during the treatment were documented and analyzed through the electronic medical record system in the hospital. All the patients were followed up regularly. The primary endpoint of this study was progression-free survival (PFS), secondary endpoints were objective response rate (ORR), disease control rate (DCR), overall survival (OS), safety profile and PFS analysis according to adverse reactions.

Results

A total of 83 patients with ESCC who received anlotinib monotherapy were included. Partial response was observed in 7 patients, stable disease was noted in 51 patients and progressive disease was found in 25 patients, which yielded an ORR of 8.4% (95% CI: 3.5–16.6%), and a DCR of 69.9% (95% CI: 58.8–79.5%). Furthermore, the median PFS of the 83 patients with advanced ESCC was 3.3 months (95% CI: 2.20–4.40) and the median OS was 7.8 months (95% CI: 5.40–10.20). Common adverse reactions among the 83 patients were hypertension (51.8%), fatigue (48.2%), weight loss (41.0%), diarrhea (34.9) and hand-foot syndrome (30.1%). Correlation analysis between hypertension status and PFS suggested that PFS of the patients with hypertension was longer than that of those with non-hypertension (median PFS: 4.5 vs 3.0 months, P = 0.019).

Conclusion

Anlotinib monotherapy demonstrated promising efficacy and tolerable toxicity for patients with previously treated advanced or metastatic ESCC. Hypertension that occurs during anlotinib administration might be used as a potential biomarker to predict PFS of patients with ESCC. The conclusion should be confirmed in prospective clinical trials subsequently.

Matrix Effectors in the Pathogenesis of Keratinocyte-Derived Carcinomas

Basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC), referred to as keratinocyte carcinomas, are skin cancer with the highest incidence. BCCs, rarely metastasize; whereas, though generally not characterized by high lethality, approximately 2–4% of primary cSCCs metastasize with patients exhibiting poor prognosis. The extracellular matrix (ECM) serves as a scaffold that provides structural and biological support to cells in all human tissues. The main components of the ECM, including fibrillar proteins, proteoglycans (PGs), glycosaminoglycans (GAGs), and adhesion proteins such as fibronectin, are secreted by the cells in a tissue-specific manner, critical for the proper function of each organ. The skin compartmentalization to the epidermis and dermis compartments is based on a basement membrane (BM), a highly specialized network of ECM proteins that separate and unify the two compartments. The stiffness and assembly of BM and tensile forces affect tumor progenitors' invasion at the stratified epithelium's stromal border. Likewise, the mechanical properties of the stroma, e.g., stiffness, are directly correlated to the pathogenesis of the keratinocyte carcinomas. Since the ECM is a pool for various growth factors, cytokines, and chemokines, its' intense remodeling in the aberrant cancer tissue milieu affects biological functions, such as angiogenesis, adhesion, proliferation, or cell motility by regulating specific signaling pathways. This review discusses the structural and functional modulations of the keratinocyte carcinoma microenvironment. Furthermore, we debate how ECM remodeling affects the pathogenesis of these skin cancers.

Tumor immunotherapies by immune checkpoint inhibitors (ICIs); the pros and cons

The main breakthrough in tumor immunotherapy was the discovery of immune checkpoint (IC) proteins, which act as a potent suppressor of the immune system by a myriad of mechanisms. After that, scientists focused on the immune checkpoint molecules mainly. Thereby, much effort was spent to progress novel strategies for suppressing these inhibitory axes, resulting in the evolution of immune checkpoint inhibitors (ICIs). Then, ICIs have become a promising approach and shaped a paradigm shift in tumor immunotherapies. CTLA-4 plays an influential role in attenuation of the induction of naïve and memory T cells by engagement with its responding ligands like B7-1 (CD80) and B7-2 (CD86). Besides, PD-1 is predominantly implicated in adjusting T cell function in peripheral tissues through its interaction with programmed death-ligand 1 (PD-L1) and PD-L2. Given their suppressive effects on anti-tumor immunity, it has firmly been documented that ICIs based therapies can be practical and rational therapeutic approaches to treat cancer patients. Nonetheless, tumor inherent or acquired resistance to ICI and some treatment-related toxicities restrict their application in the clinic. The current review will deliver a comprehensive overview of the ICI application to treat human tumors alone or in combination with other modalities to support more desired outcomes and lower toxicities in cancer patients. Video Abstract.

MicroRNA mimics can distort physiological microRNA effects on immune checkpoints by triggering an antiviral interferon response

The microRNA-200 family has wide-ranging regulatory functions in cancer development and progression. Above all, it is strongly associated with the epithelial-to-mesenchymal transition (EMT), a process during which cells change their epithelial to a mesenchymal phenotype and acquire invasive characteristics. More recently, miR-200 family members have also been reported to impact the immune evasion of cancer cells by regulating the expression of immunoinhibitory immune checkpoints (ICs) like PD-L1. Therefore, we aimed to comprehensively characterize this miR-200 family as a regulatory interface between EMT and immune evasion mechanisms in biliary tract cancer. Initial correlation analyses and transient overexpression experiments using miRNA mimics suggested miR-200c-3p as a putative regulator of ICs including PD-L1, LGALS9, and IDO1. However, these effects could not be confirmed in stable miR-200c-3p overexpression cell lines, nor in cells transiently transfected with miR-200c-3p mimic from an independent manufacturer. By shifting our efforts towards dissecting the mechanisms leading to these disparate effects, we observed that the initially used miR-200c-3p mimic triggered a double-stranded (ds)RNA-dependent antiviral response. Besides upregulating the ICs, this had substantial cellular consequences including an induction of interferon type I and type III expression, increased levels of intracellular dsRNA sensors, and a significantly altered cellular growth and apoptotic activity.Our study highlights the capability of miRNA mimics to non-specifically induce a dsRNA-mediated antiviral interferon response. Consequently, phenotypic alterations crucially distort physiological miRNA functions and might result in a major misinterpretation of previous and future miRNA studies, especially in the context of IC regulation.

Correlation between High PD-L1 and EMT/Invasive Genes Expression and Reduced Recurrence-Free Survival in Blood-Circulating Tumor Cells from Patients with Non-Muscle-Invasive Bladder Cancer

BACKGROUND

PD-L1 represents a crucial immune checkpoint molecule in the tumor microenvironment, identified as a key target for cancer immunotherapy. A correlation between PD-L1 and EMT-related genes expression in various human cancers has been suggested.

METHODS

By ScreenCell filtration, digital droplet PCR and confocal microscopy analysis, we aimed to investigate the expression of PD-L1 and EMT/invasive genes (TWIST1, ZEB1, VIMENTIN, TIMP2) in circulating tumor cells (CTCs) collected from the blood of non-muscle-invasive bladder cancer (NMIBC) patients, assessing the prognostic value of these biomarkers in the disease. Welchs' test and Mann-Whitney U test, correlation index, Kaplan-Meier, Univariate and Multivariate Cox hazard proportional analysis were used.

RESULTS

Higher PD-L1, TIMP2 and VIM mRNA levels were found in pT1 compared to pTa NMIBC. As evaluated by Kaplan-Meier and Univariate and Multivariate Cox analysis, enhancement of PD-L1, TWIST1 and TIMP2 expression reduces the recurrent free survival in NMIBC patients.

CONCLUSIONS

High PD-L1, TWIST1 and TIMP2 mRNAs mark the recurrent-NMIBC patients and by reducing the RFS represent negative prognostic biomarkers in these patients.

Epithelial-to-Mesenchymal Transition in the Light of Plasticity and Hybrid E/M States

Epithelial-to-mesenchymal transition (EMT) is a cellular program which leads to cells losing epithelial features, including cell polarity, cell-cell adhesion and attachment to the basement membrane, while gaining mesenchymal characteristics, such as invasive properties and stemness. This program is involved in embryogenesis, wound healing and cancer progression. Over the years, the role of EMT in cancer progression has been heavily debated, and the requirement of this process in metastasis even has been disputed. In this review, we discuss previous discrepancies in the light of recent findings on EMT, plasticity and hybrid E/M states. Moreover, we highlight various tumor microenvironmental cues and cell intrinsic signaling pathways that induce and sustain EMT programs, plasticity and hybrid E/M states. Lastly, we discuss how recent findings on plasticity, especially on those that enable cells to switch between hybrid E/M states, have changed our understanding on the role of EMT in cancer metastasis, stemness and therapy resistance.