Potential Therapeutic Target For Esophageal Squamous Cell Carcinoma Research Articles

CircRNA-DOPEY2 enhances the chemosensitivity of esophageal cancer cells by inhibiting CPEB4-mediated Mcl-1 translation

BackgroundCisplatin-based chemotherapy is a mainstay systematic therapy for advanced esophageal squamous cell carcinoma (ESCC), and cisplatin resistance, which is not uncommon, is the major barrier to improving patient outcomes. Circular RNAs (circRNAs) are novel noncoding RNAs that are implicated in cancer progression, but their involvement in modulating cisplatin responsiveness in ESCC remains unknown.MethodsBioinformatics analysis was used to profile and identify the circRNAs involved in cisplatin responsiveness in ESCC. The chemosensitive role of cDOPEY2 was confirmed both in vitro and in vivo. The molecular mechanism of cDOPEY2 was investigated by mass spectrometry, immunoprecipitation, and ubiquitination analyses.ResultsWe report that a novel circRNA (cDOPYE2, hsa_circ_0008078) was markedly downregulated in cisplatin-resistant ESCC cells (ESCC-CR) compared with parental chemosensitive cells. Re-expression of cDOPEY2 substantially enhanced the cell-killing ability of cisplatin by augmenting the apoptotic process in ESCC-CR cells, which was achieved by decreasing the abundance of the antiapoptotic protein Mcl-1. Mechanistically, we showed that cDOPEY2 acted as a protein scaffold to enhance the interaction between the cytoplasmic polyadenylation element binding protein (CPEB4) and the E3 ligase TRIM25, which in turn facilitated the ubiquitination and degradation of CPEB4. The increased Mcl-1 expression in ESCC-CR cells was dependent on the binding of CPEB4 to its untranslated mRNA, and depletion of CPEB4 mediated by cDOPEY2 reversed this effect. Rescue experiments confirmed that the critical role of cDOPEY2 in maintaining cisplatin sensitivity was dependent on the depletion of CEPB4 and its downstream target Mcl-1. Clinical and in vivo data further corroborated the significant relevance of cDOPEY2 to cisplatin responsiveness in ESCC.ConclusionsWe provide evidence that cDOPEY2 inhibits CPEB4-mediated Mcl-1 translation by promoting the ubiquitination and degradation of CPEB4 to alleviate cisplatin resistance, indicating that cDOPEY2 may serve as a valuable biomarker and potential therapeutic target in ESCC.

Development and Validation of a Ferroptosis-Related Gene Signature and Nomogram for Predicting the Prognosis of Esophageal Squamous Cell Carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a common malignant tumor with high mortality and poor prognosis. Ferroptosis is a newly discovered form of cell death induced by iron-catalyzed excessive peroxidation of polyunsaturated fatty acids (PUFAs). However, the prognostic value of ferroptosis-related genes (FRGs) for ESCC remains unclear. Based on the ESCC dataset from the Gene Expression Omnibus (GEO) database, we identified 39 prognostic FRGs through univariate Cox regression analysis. After LASSO regression and multivariate Cox regression analyses, a multigene signature based on 10 prognostic FRGs was constructed and successfully divided ESCC patients into two risk groups. Patients in the low-risk group showed a significantly better prognosis than patients in the high-risk group. In addition, we combined the risk score with clinical predictors to construct a nomogram for ESCC. The predictive ability of the nomogram was further verified by ROC curves and calibration plots in both the training and validation sets. The predictive power of the nomogram was demonstrated to be better than that of either the risk score or clinical variable alone. Furthermore, functional analysis revealed that the 10-FRG signature was mainly associated with ferroptosis, differentiation and immune response. Connectivity map analysis identified potential compounds capable of targeting FRGs in ESCC. Finally, we demonstrated the prognostic value of SRC gene in ESCC using the clinical samples and found that SRC inhibition sensitized ESCC cells to ferroptosis inducers by in vitro experiments. In conclusion, we identified and verified a 10-FRG prognostic signature and a nomogram, which provide individualized prognosis prediction and provide insight into potential therapeutic targets for ESCC.

LncRNA SNHG17 regulates cell proliferation and invasion by targeting miR-338-3p/SOX4 axis in esophageal squamous cell carcinoma

Small nucleolar RNA host gene 17 (SNHG17), a novel functional long noncoding RNA, has been demonstrated to play an essential role in the oncogenesis of several tumors. However, for esophageal squamous cell carcinoma (ESCC) the expression pattern and detailed function of SNHG17 are largely unknown. Hence, we conducted this study to explore potential roles and underlying oncogenic mechanisms for SNHG17 in ESCC progression. Results demonstrated SNHG17 to be markedly upregulated in ESCC. Knockdown of SNHG17 significantly suppressed ESCC cell proliferation, invasion, and epithelial–mesenchymal transition in vitro and tumor growth in vivo. Online database software analysis found miR-338-3p to interact with SNHG17 with the level of miR-338-3p negatively correlated with SNHG17 levels in ESCC samples. Further, miR-338-3p was found to directly target SRY-box transcription factor 4 (SOX4) in ESCC cells. Mechanistic analysis suggested that SNHG17 acts as an endogenous “sponge” competing with miR-338-3p to regulate SOX4, thereby promoting tumor progression. These results suggest that these molecular interactions may be potential therapeutic targets for ESCC.

Elevated expression of the RNA\u2010binding motif protein 43 predicts poor prognosis in esophageal squamous cell carcinoma

RNA-binding proteins (RBPs) play crucial roles in the post-transcriptional regulation of mRNA during numerous physiological and pathological processes, including tumor genesis and development. However, the role of RNA-binding motif protein 43 (RBM43) in esophageal squamous cell carcinoma (ESCC) has not been reported so far. The current study was the first to evaluate RBM43 protein expression by immunohistochemistry (IHC) in an independent cohort of 207 patients with ESCC, to explore its potential prognostic value and clinical relevance in ESCC. The results indicated that RBM43 protein levels were significantly elevated in ESCC tissues and increased RBM43 expression was associated with age and N categories. In addition, ESCC patients with high expression of RBM43 had shorter overall survival (OS) and disease‐free survival (DFS) than those with low RBM43 expression. Furthermore, when survival analyses were conducted at different clinical stages, overexpression of RBM43 was significantly correlated with shortened survival in patients with ESCC at early stages (TNM stage I–II and N0 stage). Cox regression analysis further proved that high RBM43 expression was an independent predictor of poor prognosis in ESCC patients. In conclusion, increased expression of RBM43 is correlated with malignant attributes to ESCC and predicts unfavorable prognosis, suggesting an effective prognostic biomarker and potential therapeutic target for ESCC.

Identification of potential core genes in esophageal carcinoma using bioinformatics analysis.

Background:Esophageal squamous cell carcinoma (ESCC) is a common human malignancy worldwide. The tumorigenesis mechanism in ESCC is unclear.Materials and methods:To explore potential therapeutic targets for ESCC, we analyzed 3 microarray datasets (GSE20347, GSE38129, and GSE67269) derived from the gene expression omnibus (GEO) database. Then, the GEO2R tool was used to screen out differently expressed genes (DEGs) between ESCC and normal tissue. Gene ontology function and kyoto encyclopedia of genes and genomes pathway enrichment analysis were performed using the database for annotation, visualization and integrated discovery to identify the pathways and functional annotation of DEGs. Protein–protein interaction of these DEGs was analyzed based on the search tool for the retrieval of interacting genes database and visualized by Cytoscape software. In addition, we used encyclopedia of RNA interactomes (ENCORI), gene expression profiling interactive analysis (GEPIA), and the human protein atlas to confirm the expression of hub genes in ESCC. Finally, GEPIA was used to evaluate the prognostic value of hub genes expression in ESCC patients and we estimated the associations between hub genes expression and immune cell populations (B Cell, CD8+ T Cell, CD4+ T Cell, Macrophage, Neutrophil, and Dendritic Cell) in esophageal carcinoma (ESCA) using tumor immune estimation resource (TIMER).Results:In this study, 707 DEGs (including 385 upregulated genes and 322 downregulated genes) and 6 hub genes (cyclin B1 [CCNB1], cyclin dependent kinase 1 [CDK1], aurora kinase A [AURKA], ubiquitin conjugating enzyme E2C [UBE2C], cyclin A2 [CCNA2], and cell division cycle 20 [CDC20]) were identified. All of the 6 hub genes were highly expressed in ESCC tissues. Among of them, only CCNB1 and CDC20 were associated with stage of ESCC and all of them were not associated with survival time of patients.Conclusion:DEGs and hub genes were confirmed in our study, providing a thorough, scientific and comprehensive research goals for the pathogenesis of ESCC.

Clinical significance of signal regulatory protein alpha (SIRPα) expression in esophageal squamous cell carcinoma

Signal regulatory protein alpha (SIRPα) is a type I transmembrane protein that inhibits macrophage phagocytosis of tumor cells upon interaction with CD47, and the CD47‐SIRPα pathway acts as an immune checkpoint factor in cancers. This study aims to clarify the clinical significance of SIRPα expression in esophageal squamous cell carcinoma (ESCC). First, we assessed SIRPα expression using RNA sequencing data of 95 ESCC tissues from The Cancer Genome Atlas (TCGA) and immunohistochemical analytic data from our cohort of 131 patients with ESCC. Next, we investigated the correlation of SIRPα expression with clinicopathological factors, patient survival, infiltration of tumor immune cells, and expression of programmed cell death‐ligand 1 (PD‐L1). Overall survival was significantly poorer with high SIRPα expression than with low expression in both TCGA and our patient cohort (P < .001 and P = .027, respectively). High SIRPα expression was associated with greater depth of tumor invasion (P = .0017). Expression of SIRPα was also significantly correlated with the tumor infiltration of M1 macrophages, M2 macrophages, CD8+ T cells, and PD‐L1 expression (P < .001, P < .001, P = .03, and P < .001, respectively). Moreover, patients with SIRPα/PD‐L1 coexpression tended to have a worse prognosis than patients with expression of either protein alone or neither. Taken together, SIRPα indicates poor prognosis in ESCC, possibly through inhibiting macrophage phagocytosis of tumor cells and inducing suppression of antitumor immunity. Signal regulatory protein alpha should be considered as a potential therapeutic target in ESCC, especially if combined with PD‐1‐PD‐L1 blockade.

LncRNA LOC146880 promotes esophageal squamous cell carcinoma progression via miR-328-5p/FSCN1/MAPK axis.

We investigated the role of long non-coding RNA (lncRNA) LOC146880 in esophageal squamous cell carcinoma (ESCC). LOC146880 was significantly upregulated in ESCC tissues (n = 21) and cell lines compared to the corresponding controls. Higher LOC146880 expression correlated with poorer overall survival (OS) of ESCC patients. Moreover, CREB-binding protein (CBP) and H3K27 acetylation levels were significantly higher in the LOC146880 promoter in ESCC cell lines than in the controls. LOC146880 silencing inhibited in vitro proliferation, invasion, migration, and epithelial-mesenchymal transition of ESCC cells. LOC146880 silencing also induced G1-phase cell cycle arrest and apoptosis in ESCC cells. Bioinformatics analysis, dual luciferase reporter assays, and RNA immunoprecipitation assays showed that LOC146880 regulates FSCN1 expression in ESCC cells by sponging miR-328-5p. Moreover, FSCN1 expression correlated with activation of the MAPK signaling pathway in ESCC cells and tissues. In vivo xenograft tumor volume and liver metastasis were significantly reduced in nude mice injected with LOC146880-silenced ESCC cells as compared to those injected with control shRNA-transfected ESCC cells. These findings show that the LOC146880/miR-328-5p/FSCN1/MAPK axis regulates ESCC progression in vitro and in vivo. LOC146880 is thus a promising prognostic biomarker and potential therapeutic target in ESCC.

Tissue-based metabolomics reveals metabolic biomarkers and potential therapeutic targets for esophageal squamous cell carcinoma

Prognosis for esophageal squamous cell carcinoma (ESCC) is poor, so it is essential to develop a more complete understanding of the disease. The purpose of this study was to explore metabolic biomarkers and potential therapeutic targets for ESCC. An ultra-high-performance liquid chromatography coupled with high resolution mass (UPLC/MS)-based metabolomic analysis was performed in 141 ESCC cancerous tissue samples and 70 non-cancerous counterparts. The results showed that 41 differential metabolites were annotated in the training set, and 37 were validated in the test set. Single-metabolite-based receiver operating characteristic (ROC) curves as well as metabolite-based machine learning models, including Partial Least Squares (PLS), Support Vector Machine (SVM), and Random Forest (RF), were investigated for cancerous and non-cancerous tissue classification. Six most prevalent diagnostic metabolites—adenylsuccinic acid, UDP-GalNAc, maleylacetoacetic acid, hydroxyphenylacetylglycine, galactose, and kynurenine—showed testing predictive accuracies of 0.89, 0.95, 0.97, 0.89, 0.84, and 0.84, respectively. Moreover, the metabolite-based models (PLS, SVM, and RF) had testing predictive accuracies of 0.95, 0.95, and 1.00, respectively. Kaplan–Meier survival analysis and Cox proportional hazards regression analysis demonstrated that 2-hydroxymyristoylcarnitine (HR: 0.55, 95 % CI: 0.32 to 0.92), 3-hydroxyhexadecanoylcarnitine (HR: 0.49, 95 % CI: 0.29 to 0.83), and 2,3-Dinor-TXB1 (HR: 0.56, 95 % CI: 0.33 to 0.95) to be significantly associated with OS. Based on the observation of accumulation in amino acids, immunohistochemistry (IHC) staining revealed that the amino acid transporters SLC7A5/LAT1, SLC1A5/ASCT2, and SLC16A10/MCT10 were up-regulated in ESCC cancerous tissues when compared to non-cancerous equivalents. Consistently, the same panel of amino acids were downregulated in cells with SLC1A5 knockdown. Herein, it is concluded that this study not only identified several metabolites with diagnostic and/or prognostic value, but also provided accurate metabolite-based prediction models for ESCC tissue classification. Furthermore, the three up-regulated amino acid transporters were identified as potential therapeutic targets for ESCC, especially SLC1A5.

Long non‑coding RNA LINC00491 promotes proliferation and inhibits apoptosis in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a common malignant tumor in the human digestive system, which affects the physical and mental health of the patient. Long non-coding (lnc)RNAs have been revealed to play an important role in human malignant tumors. Moreover, long intergenic non-protein coding RNA 491 (LINC00491) is a newly discovered lncRNA that can affect the prognosis of cancer. The present study aimed to explore the expression of LINC00491 in ESCC tissues and cells. The reverse transcription-quantitative PCR results suggested that LINC00491 was upregulated in ESCC tissues and cells. LINC00491 expression in esophageal squamous cell carcinoma cells were knocked down. Cell Counting Kit-8, wound healing, Transwell and apoptosis assays were performed to detect the effects of LINC00491 knockdown on cell biological behavior. The results showed that lower expression of LINC00491 resulted in decreased cell proliferation and migration and increased the apoptosis rate. Therefore, the present results indicated that lncRNA LINC00491 promoted the biological processes of ESCC, and thus LINC00491 may be a potential therapeutic target for ESCC.

Cancer-associated fibroblasts-derived exosomal miR-3656 promotes the development and progression of esophageal squamous cell carcinoma via the ACAP2/PI3K-AKT signaling pathway.

Esophageal squamous cell carcinoma (ESCC) is one of the most common gastrointestinal tumors, accounting for almost half a million deaths per year. Cancer-associated fibroblasts (CAFs) are the major constituent of the tumor microenvironment (TME) and dramatically impact ESCC progression. Recent evidence suggests that exosomes derived from CAFs are able to transmit regulating signals and promote ESCC development. In this study, we compared different the component ratios of miRNAs in exosomes secreted by CAFs in tumors and with those from normal fibroblasts (NFs) in precancerous tissues. The mRNA level of hsa-miR-3656 was significantly upregulated in the former exosomes. Subsequently, by comparing tumor cell development in vitro and in vivo, we found that the proliferation, migration and invasion capabilities of ESCC cells were significantly improved when miR-3656 was present. Further target gene analysis confirmed ACAP2 was a target gene regulated by miR-3656 and exhibited a negative regulatory effect on tumor proliferation. Additionally, the downregulation of ACAP2 triggered by exosomal-derived miR-3656 further promotes the activation of the PI3K/AKT and β-catenin signaling pathways and ultimately improves the growth of ESCC cells both in vitro and in xenograft models. These results may represent a potential therapeutic target for ESCC and provide a new basis for clinical treatment plans.

Six Novel Biomarkers for Diagnosis and Prognosis of Esophageal squamous cell carcinoma: validated by scRNA-seq and qPCR.

Esophageal squamous cell carcinoma (ESCC) is one of the most common cancers worldwide. ESCC has a generally poor prognosis and there is a lack of available biomarkers for diagnosis and prognosis. The aim of the study was to identify novel biomarkers for ESCC. We screened the overlapping differentially expressed genes (DEGs) acquired from six Gene Expression Omnibus (GEO) ESCC datasets and The Cancer Genome Atlas (TCGA) ESCC datasets. Subsequently, protein-protein interaction network analysis was performed to identify the key hub genes. Then, Kaplan Meier survival and receiver operating curve (ROC) analysis were utilized to clarify the diagnostic and prognostic role of these hub genes. The UALCAN database, single cell RNA sequencing (scRNA-seq) and real-time quantitative PCR (qPCR) were performed to confirm the expression levels of identified hub genes. Finally, immune infiltration analysis was conducted to investigate the role of these genes in the pathogenesis of ESCC. The results showed that PBK, KIF2C, NUF2, KIF20A, RAD51AP1, and DEPDC1 effectively distinguish ESCC tissues from normal samples, and all of them were significantly correlated with overall survival. The results of scRNA-seq and qPCR indicated that the expression levels of hub genes in ESCC were significantly higher than in normal cells or tissues. Further immune infiltration analysis showed that infiltration of dendritic cells was significantly negatively correlated with PBK, KIF2C, NUF2, RAD51AP1, and DEPDC1 expression levels. In conclusion, our results suggest that PBK, KIF2C, NUF2, KIF20A, RAD51AP1 and DEPDC1 are all potential biomarkers for ESCC diagnosis and prognosis may also be potential therapeutic targets for ESCC.

CXCR4 Promotes Growth and Metastasis of Esophageal Squamous Cell Carcinoma as a Critical Downstream Mediator of HIF-1α

Background: Recent studies have shown that C-X-C chemokine receptor 4(CXCR4) plays an important role in a variety of tumours. However, its role and regulated mechanism in esophageal squamous cell carcinoma (ESCC) remain unclear. Methods: Immunohistochemistry, Western blot and qPCR were used to detect the expression of CXCR4 and HIF-1α. HIF-1α downstream target gene was detected by RNA-seq. The invasion and metastasis ability of HIF-1α/CXCR4 axis to ESCC cells were detected by transwell and animal experiments. Dual-luciferase analysis and chromatin immunoprecipitation assay showed that HIF-1α directly binds to the HRE site in the CXCR4 promoter. Findings: We showed that CXCR4 was enriched in ESCC tissues compared with corresponding normal tissues and predicted lymph node metastasis and poor prognosis. CXCR4 overexpression promotes the proliferation, migration and invasion of ESCC. In addition, we revealed that hypoxia-inducible factor-1α (HIF-1α) regulated CXCR4 expression via binding to a hypoxia response element in its promoter, and the HIF-1α-enhanced metastasis ability of ESCC cells was reversed by CXCR4 knockdown or treatment with MSX-122, a CXCR4 antagonist. Interpretation: In showing that the dysregulated HIF-1α/CXCR4 axis promotes ESCC malignancy, the results suggested that CXCR4 is a potential therapeutic target for ESCC. Funding: This research was supported by the National Natural Science Foundation of China (81772619, 82002551), the Science and Technology Project of Tianjin Municipal Health Commission (RC20119), the Bethune Charitable Foundation-Excelsior Surgical Fund (HZB-20190528-18), and the Clinical Trial Project of Tianjin Medical University (2017kylc006). Declaration of Interest: The authors declare no conflict of interest. Ethical Approval: All operations for human subjects were approved by the ethics committee of our hospital, and all patients provided informed consent. Gene Expression Omnibus (GEO) data were downloaded from the website (https://www.ncbi.nlm.nih.gov/geo/).

Pharmaceutical inhibition of AXL suppresses tumor growth and invasion of esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is a common type of cancer in a number of regions of the world, including East Asia, South Africa and Iran. It is often associated with poor prognosis rates. Tyrosine-protein kinase receptor UFO (AXL) is overexpressed in a subset of ESCC tumors, therefore the present study aimed to determine the effect of R428, a selective inhibitor of AXL, on ESCC tumor cells. TE1 and KYSE150 cell lines were used as models to investigate the effects of R428 treatment. The proliferative rate of the tumor cells was analyzed using MTT and colony formation assays. In addition, cell migration and invasion rates were analyzed using wound healing and Matrigel assays, respectively. The expression levels of matrix metalloproteinase (MMP)2 and MMP9, and the activation of protein kinase B (AKT), extracellular signal-regulated kinase (ERK) and AXL signaling were analyzed using gelatin zymography and western blotting. The results revealed that R428 inhibited the proliferative and invasive abilities of both cell lines. Furthermore, AXL, AKT and ERK signaling were all decreased in response to R428 treatment, alongside the expression levels of MMP2 and MMP9. In conclusion, the results of the present study suggested that R428 treatment may suppress ESCC tumor cell proliferation and invasion, representing a potential therapeutic target for ESCC.

Combined Metabolomic Analysis of Plasma and Tissue Reveals a Prognostic Risk Score System and Metabolic Dysregulation in Esophageal Squamous Cell Carcinoma

Background: Esophageal squamous cell carcinoma (ESCC) is a gastrointestinal malignancy with a poor prognosis. Although studies have shown metabolic reprogramming to be linked to ESCC development, no prognostic metabolic biomarkers or potential therapeutic metabolic targets have been identified.Method: The present study investigated some circulating metabolites associated with overall survival in 276 curatively resected ESCC patients using liquid chromatography/mass spectrometry metabolomics and Kaplan-Meier analysis. Tissue metabolomic analysis of 23-paired ESCC tissue samples was performed to discover metabolic dysregulation in ESCC cancerous tissue. A method consisting of support vector machine recursive feature elimination and LIMMA differential expression analysis was utilized to select promising feature genes within transcriptomic data from 179-paired ESCC tissue samples. Joint pathway analysis with genes and metabolites identified relevant metabolic pathways and targets for ESCC.Results: Four metabolites, kynurenine, 1-myristoyl-glycero-3-phosphocholine (LPC(14:0)sn-1), 2-piperidinone, and hippuric acid, were identified as prognostic factors in the preoperative plasma from ESCC patients. A risk score consisting of kynurenine and LPC(14:0)sn-1 significantly improved the prognostic performance of the tumor-node-metastasis staging system and was able to stratify risk for ESCC. Combined tissue metabolomic analysis and support vector machine recursive feature elimination gene selection revealed dysregulated kynurenine pathway as an important metabolic feature of ESCC, including accumulation of tryptophan, formylkynurenine, and kynurenine, as well as up-regulated indoleamine 2,3-dioxygenase 1 in ESCC cancerous tissue.Conclusions: This work identified for the first time four potential prognostic circulating metabolites. In addition, kynurenine pathway metabolism was shown to be up-regulated tryptophan-kynurenine metabolism in ESCC. Results not only provide a metabolite-based risk score system for prognosis, but also improve the understanding of the molecular basis of ESCC onset and progression, and as well as novel potential therapeutic targets for ESCC.

LncRNA MAFG-AS1 Contributes to Esophageal Squamous-Cell Carcinoma Progression via Regulating miR143/LASP1.

BackgroundIncreasing investigations indicate that long noncoding RNA (lncRNA) is responsible for diverse biological functions during the progression of cancer. However, its functions and underlying mechanisms remain elusive. Here, we investigated the MAFG-AS1- expression profile in esophageal squamous-cell carcinoma (ESCC) patients and explored its biological function and potential molecular mechanisms.MethodsqRT-PCR and the GEPIA data base were used to evaluate expression levels of MAFG-AS1 in ESCC tissue and cells. WST1-proliferation, -migration, and -invasion assays were performed to define the role of MAFG-AS1 in ESCC. Potential molecular mechanisms of MAFG-AS1 were investigated with online bioinformatic analysis, qRT-PCR, and rescue assays.ResultsMAFG-AS1 was upregulated in 45 ESCC-tissue samples and cell lines compared to that of adjacent nontumor tissue and normal esophageal cells. Higher MAFG-AS1 expressionindicated poor survival. Gain- and loss-of-function experiments suggested that MAFG-AS1 promoted ESCC-cell proliferation, migration, and invasion. Molecular mechanism analysis and rescue assay showed that miR143 inhibitors partly abolished the suppression of MAFG-AS1 knockdown on EC109-cells proliferation. Moreover, we found that LASP1 specifically targeted miR143. Collectively, these data indicated that MAFG-AS1 served as a ceRNA to elevate LASP1 levels by sponging miR143, and played an oncogenic role in ESCC.ConclusionOur research findings demonstrate that MAFG-AS1 is a key regulator through a novel MAFG-AS1–miR143–LASP1 axis in ESCC development and progression, which may offer a potential therapeutic target for ESCC.

Potential therapeutic effect of targeting glycogen synthase kinase 3\u03b2 in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a common gastrointestinal cancer and is often refractory to current therapies. Development of efficient therapeutic strategies against ESCC presents a major challenge. Glycogen synthase kinase (GSK)3β has emerged as a multipotent therapeutic target in various diseases including cancer. Here we investigated the biology and pathological role of GSK3β in ESCC and explored the therapeutic effects of its inhibition. The expression of GSK3β and tyrosine (Y)216 phosphorylation-dependent activity was higher in human ESCC cell lines and primary tumors than untransformed esophageal squamous TYNEK-3 cells from an ESCC patient and tumor-adjacent normal esophageal mucosa. GSK3β-specific inhibitors and small interfering (si)RNA-mediated knockdown of GSK3β attenuated tumor cell survival and proliferation, while inducing apoptosis in ESCC cells and their xenograft tumors in mice. GSK3β inhibition spared TYNEK-3 cells and the vital organs of mice. The therapeutic effect of GSK3β inhibition in tumor cells was associated with G0/G1- and G2/M-phase cell cycle arrest, decreased expression of cyclin D1 and cyclin-dependent kinase (CDK)4 and increased expression of cyclin B1. These results suggest the tumor-promoting role of GSK3β is via cyclin D1/CDK4-mediated cell cycle progression. Consequently, our study provides a biological rationale for GSK3β as a potential therapeutic target in ESCC.

Expression of microRNA-17-5p in esophageal squamous cell carcinoma and its effects on cell proliferation and invasion

Objective: To explore the expression of microRNA-17-5p (miR-17-5p) in esophageal squamous cell carcinoma (ESCC) and its effects on cell proliferation and invasion ability. Methods: Real-time quantitative PCR (RT-qPCR) was used to detect the miR-17-5p level in ESCC tissues and cells. MiR-17-5p inhibitor and negative control (NC) were transfected into EC9706 and TE1 cells, and miR-17-5p expression was examined by using RT-qPCR. Cell counting kit-8 (CCK-8) and EdU were conducted to detect cell proliferation and Transwell chamber was used to investigate cell invasion ability. Dual-luciferase reporter assay was used to detect the direct interaction of miR-17-5p and retinoblastoma-like protein-2 (RBL2). Western blot and RT-qPCR were used to detect the expression of RBL2 in ESCC tissues, respectively. Finally, the correlation between RBL2 and miR-17-5p was analyzed. Results: The miR-17-5p level in ESCC tissues was 4.222±0.392, significantly higher than 1.081±0.046 in normal esophageal epithelial tissues (P<0.001). The expressions of miR-17-5p in ESCC cells, including EC9706, Eca109, TE1, KYSE450, KYSE70 and KYSE520, were 13.84±1.266, 6.453±0.293, 11.41±0.520, 2.613±0.548, 5.251±0.239 and 4.251±0.195, respectively, all obviously higher than (1.007±0.079) in normal esophageal epithelial cell Het-1A (P<0.05). The miR-17-5p level in patients with ESCC Ⅲ~Ⅳ was 5.094±0.562, markedly higher than 2.934±0.364 in patients with ESCCⅠ~Ⅱ(P<0.01). Moreover, the miR-17-5p level in ESCC patients with lymph node metastasis was 5.523±0.634, markedly higher than 3.533±0.461 in ESCC patients without lymph node metastasis (P<0.05). The survival ratio of ESCC patients with higher miR-17-5p level was evidently lower than that of ESCC patients with lower miR-17-5p level (P<0.05). MiR-17-5p inhibitor significantly downregulated the miR-17-5p expression in EC9706 and TE1, which suppressed cell proliferation and invasion ability. Dual-luciferase reporter assay revealed that co-transfection of 3' untranslated region-wild type (3'UTR-WT) of RBL2 and miR-17-5p mimic significantly reduced luciferase activity in EC9706 and TE1 cells (P<0.01), which implicated that RBL2 was the direct target of miR-17-5p. The result of western blot revealed that RBL2 protein expressions in miR-17-5p group of EC9706 and TE1 cells were 0.936±0.055 and 0.923±0.048, obviously higher than 0.087±0.019 and 0.102±0.010 in control group (P<0.001). The expression of RBL2 in ESCC tissues was 0.219±0.510, markedly lower than 0.983±0.324 in normal esophageal epithelial tissues (P<0.001). The miR-17-5p level exhibited a negative correlation with RBL2 level in ESCC tissues (r=-0.462, P<0.001). Downregulation of RBL2 reversed the miR-17-5p inhibitor induced suppression of cell proliferation and invasion ability. Conclusion: MiR-17-5p participates in the carcinogenesis and development of ESCC, thus may be a potential therapeutic target for ESCC patients.

High Expression of Methylenetetrahydrofolate Dehydrogenase 2 (MTHFD2) in Esophageal Squamous Cell Carcinoma and its Clinical Prognostic Significance.

BackgroundRecently, targeted therapy for malignant tumors has developed rapidly, but there is still no effective targeted therapy for advanced esophageal squamous cell carcinoma (ESCC). Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) is a key enzyme involved in folate metabolism and is closely related to the proliferation in many cancers. However, few studies have explored the expression of MTHFD2 in ESCC and its prognostic significance.Material/MethodsThe expressions of MTHFD2, ki67, and p53 in ESCC tissues were detected by immunohistochemistry. Further, MTHFD2 expression level in ESCC and its correlations with patients’ clinicopathological characteristics and survival prognosis were investigated.ResultsThe enhanced expression of MTHFD2 was observed in ESCC specimens compared with adjacent normal tissue. The increased expression of MTHFD2 was closely related to pathological grading (P=0.020) and tumor TNM stage (P=0.019). In addition, patients with high expression of MTHFD2 had worse survival than those with low MTHFD2 expression (P<0.05). High expression of MTHFD2 in ESCC tissues was often associated with high expression of ki67 and p53 (P<0.05).ConclusionsMTHFD2 had significantly enhanced expression in ESCC tissues and was associated with pathological grading and TNM stage. Taken together, high expression of MTHFD2 was an independent unfavorable prognostic parameter for overall survival (OS) of ESCC patients, suggesting that MTHFD2 might be a potential therapeutic target for ESCC in the future.

LncRNA MIAT promotes esophageal squamous cell carcinoma progression by regulating miR-1301-3p/INCENP axis and interacting with SOX2.

Long noncoding RNAs (lncRNAs) have been reported to participate in the development of multiple cancers, including esophageal squamous cell carcinoma (ESCC). A growing number of studies have demonstrated that lncRNA myocardial infarction-associated transcript (MIAT) played an oncogenic role in several human malignancies, but its expression and function in ESCC remain unknown. In this study, we found that MIAT was significantly increased in ESCC tissues, as well as cell lines. Downregulation of MIAT suppressed ESCC cell proliferation, cell cycle, migration, and invasion. Mechanical studies revealed that MIAT promoted ESCC cell proliferation and cell cycle by acting as a competitively endogenous RNA (ceRNA) to upregulate the inner centromere protein (INCENP) expression through sponging miR-1301-3p. Furthermore, we uncovered that MIAT-SOX2 formed a positive feedback loop to facilitate cell proliferation, migration, and invasion of ESCC. Our findings indicated that MIAT promoted ESCC progression via targeting INCENP/miR-1301-3p axis and interacting with SOX2, suggesting novel potential therapeutic targets for ESCC.

Prognostic value and functional bioinformatic analysis of spindle- and kinetochore-associated protein 1 in stage IIA esophageal squamous cell carcinoma.

As one of the most common malignant tumors of the digestive tract, esophageal squamous cell carcinoma (ESCC) is an advanced metastatic cancer with an extremely high mortality rate and the highest prevalence rate in China. Spindle- and kinetochore-associated protein 1 (SKA1), an essential member involved in chromosome separation during mitosis, has been indicated as a potential biomarker in the pathogenesis and development of various types of malignant tumors; however, the exact functions of SKA1 in ESCC are still unclear. SKA1 expression was explored in stage IIA ESCC and corresponding healthy esophageal mucosa tissues through immunohistochemistry and reverse transcription-quantitative polymerase chain reaction and was further validated using The Cancer Genome Atlas (TCGA) database of the online tool UALCAN. Then, the clinicopathological correlations of SKA1 were analyzed based on the follow-up data. Furthermore, using the online tool LinkedOmics, the correlation test, gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis of SKA1 were analyzed using high-throughput sequencing data of ESCC patients from TCGA dataset. The expression level of SKA1 was markedly upregulated in ESCC tissues. Upregulation of SKA1 significantly correlated with higher pathological T stage (P = 0.003) and poorer overall survival (P = 0.013). GO and pathway enrichment analyses of SKA1 in ESCC revealed that SKA1 was involved in a number of classical cell cycle-related pathways that contribute to special biological processes in tumorigenesis and development of ESCC. The results of this study demonstrate that SKA1 may act as a prognostic biomarker for stage IIA ESCC. Combined with the bioinformatic analysis, SKA1 could potentially serve as a therapeutic target for ESCC. The results coming from the present study demonstrated that SKA1 may act as a prognostic biomarker for stage IIA ESCC. Combined with the bioinformatic analysis, SKA1 could serve as a potential therapeutic target for ESCC.