Esophageal Squamous Cell Carcinoma Tissues Research Articles

439. INTEGRATION OF SCRNA-SEQ AND BULK RNA-SEQ TO VALIDATE A PROGNOSTIC ASSOCIATED SIGNATURE IN ESOPHAGEAL SQUAMOUS CELL CARCINOMA

Abstract Background Considerable evidence has identified important targets for esophageal squamous cell carcinoma (ESCC), but its efficacy and the heterogeneity of ESCC are the main causes of treatment failure. Single-cell RNA-sequencing (scRNA-seq) is a powerful tool for analyzing tumor heterogeneity at the single-cell level and helps to better identify potential therapeutic targets. Methods ESCC scRNA-seq data were extracted from the Gene Expression Omnibus (GEO) database. Single-sample gene set enrichment analysis (ssGSEA) was performed using the limma package to analyze ESCC-associated prognostic marker genes from ESCC transcriptome data downloaded from the TCGA database and the results were validated with transcriptomic data from 56 ESCC patients in our hospital. KEGG (Kyoto Encyclopedia of Genes and Genomes) and GO (Gene Ontology) analyses of prognostic marker genes were performed by GSEA. Then, univariate and multivariate Cox and lasso regressions were performed to further build signatures. Finally, qPCR was used to assess the expression of prognostic marker genes in 5 pairs ESCC samples. Results Integrate scRNA-seq (GSE53624) datasets to obtain 13 cell clusters. We characterized single-cell expression profiles of 24076 cell samples and identified 4 marker genes associated with prognosis. Four key prognostic marker genes were trained and validated on the TCGA-ESCA dataset and in 55 patients from our in-hospital cohort to evaluate predictive overall survival (OS) models. Correlation analysis showed that prognostic marker genes were independent of risk clinical characteristics. In addition, we performed Cox regression analysis, suggesting that the 4 prognostic marker genes screened were independent risk factors related to the prognosis of ESCC patients. In addition, qPCR showed that the expression of IER3 and SAA1 was decreased and the expression of CDKN3 was increased in ESCC tissues, while the expression of TINP3 was not significantly different. Conclusion We constructed prognostic marker genes by scRNA-seq and validated the model in a large patient population as well as in ESCC tissues, which provides reasonable evidence and valuable resources for prognostic stratification and the study of potential targets for ESCC.

260. LOW BLOOD LEVEL OF TUMOR SUPPRESSOR MIR-3619 AS A TARGET OF NUCLEIC ACID THERAPY TO PIM-1 IN ESOPHAGEAL CANCER

Abstract Background Numerous studies have attempted to understand the molecular mechanisms of tumorigenesis and identify clinical biomarkers and molecular targets for esophageal squamous cell carcinoma (ESCC). However, there are still only a few biomarkers and targets. We focused on tumor suppressor micro-RNA (miR)s in the plasma of ESCC patients, and we investigated the usefulness of these tumor suppressor miRs as biomarkers and therapeutic agents for ESCC. Methods: Plasma samples of 94 ESCC patients and 86 healthy volunteers were analyzed in this study. Among the group of 2600 miRs candidates registered in miRbase, we selected 25 miRs candidates which are low expressed in ESCC tissues, have tumor suppressive functions, and unreported as a body fluid biomarker. We selected 5 miRs (miR-564/ 637/ 1182/ 3178/ 3619), whose signals were detectable in the blood of healthy volunteers by microarray analysis. By test-scale analysis using TaqMan assay and validation analysis, we identified miR-3619, which showed the most significant difference in ESCC patients compared to healthy volunteers (p < 0.001). Results: 1) Prognostic analysis revealed that a low miR-3619 plasma level was significantly associated with advanced stage and recurrence rate, and was an independent factor predicting poor prognosis in ESCC patients (p = 0.028, HR = 2.09). 2) Overexpression of miR-3619 mimic inhibited the proliferation of ESCC cells, induced the accumulation of apoptosis or G1/S phase cells, and reduced the cell migration and invasion abilities compared with negative control mimic. 3) We tested PIM-1xas candidate putative target genes for miR-3619 using microRNA database. PIM-1 protein expression levels were decreased in miR-3619-5p transfectants compared with NC. 4) In vivo, subcutaneous injection of miR-3619 could significantly inhibit tumor growth in mice. Administration of miR-3619 did not cause any clinical adverse events or side effects in blood-based parameters reflecting organ disorders. Conclusion: These results suggest that depleted tumor-suppressor miR-3619 in plasma could be one of blood-based biomarkers for predicting malignant potential of ESCC.

Expression and functional analyses of TERF2 in esophageal carcinoma

BackgroundEsophageal cancer (ESCA) is a prevalent malignancy with a high incidence of morbidity and mortality, particularly in Asia. Telomeric Repeat-binding Factor 2 (TERF2) is a crucial component of the telomere-binding protein complex that maintains telomere stability. Aberrant TERF2 expression has been implicated in tumorigenesis, however, its specific role in ESCA remains largely unexplored. MethodsThe expression levels of TERF2 were assessed in esophageal squamous cell carcinoma (ESCC) samples using RT-PCR, IHC, and Western blotting (WB). Serum tumor marker concentrations were determined via electrochemiluminescence immunoassay (ECLIA) and chemiluminescent microparticle immunoassay (CMIA). Bioinformatics analyses were employed to elucidate TERF2's function in EC. The impact of TERF2 on ESCC cell proliferation was evaluated through cell counting kit-8 (CCK8) assays and flow cytometry. ResultsTERF2 protein and mRNA expression were elevated in ESCC tissues and correlated with age, sex, cancer stage, tumor grade, lymph node metastasis (LNM), and tumor histology. Univariate Cox regression analysis indicated TERF2 was an independent prognostic factor for overall survival (OS). TERF2 mRNA levels were associated with serum levels of carcinoembryonic antigen (CEA), cytokeratin 19 fragment (CYFRA21-1), and tissue polypeptide antigen (TPA) in patients with ESCC. Immune infiltration and chemokine profiles were linked to TERF2 expression in ESCA. TERF2 is involved in regulating ESCC cell proliferation may through the DDR/P53 signaling way. ConclusionsTERF2 is overexpressed in ESCA and contributes to ESCC cell proliferation may via DDR/TP53 signaling pathway. These results suggest that TERF2 may serve as a potential target for developing treatments and diagnostic biomarker for ESCA.

The TDP-43/TP63 Positive Feedback Circuit Promotes Esophageal Squamous Cell Carcinoma Progression.

Esophageal squamous cell carcinoma (ESCC) is one of the most prevalent malignancies with a 5-year survival rate of only 15% in patients with advanced diseases. Tumor protein 63 (TP63), a master transcription factor (TF) in ESCC, cooperates with other TFs to regulate enhancers and/or promoters of target oncogenes, which in turn promotes tumorigenesis. TAR-DNA-binding protein-43 (TDP-43) is an RNA/DNA binding protein with elevated expression in several neoplasms. However, it remains unclear how TDP-43 contributes to ESCC progression. In this study, TDP-43 is identified as a novel oncogene with markedly upregulated expression in ESCC tissues through profiling expression levels of one hundred and fifty canonical RNA binding protein (RBP) genes in multiple ESCC patient cohorts. Importantly, TDP-43 boosted TP63 expression via post-transcriptionally stabilizing TP63 mRNAs as a RBP and promoting TP63 transcription as a TF binding to the TP63 promoter in ESCC cells. In contrast, the master TF TP63 also bound to the TDP-43 promoter, accelerated TDP-43 transcription, and caused a noticeable increase in TDP-43 expression in ESCC cells. The findings highlight TDP-43 as a viable therapeutic target for ESCC and uncover a hitherto unrecognized TDP-43/TP63 circuit in cancer.

242. BRD4 INHIBITION ENHANCES THE RADIOSENSITIVITY OF ESOPHAGEAL SQUAMOUS CELL CARCINOMA THROUGH REGULATING ATF3-MEDIATED SERINE AND NUCLEOTIDE SYNTHESIS

Abstract Background Radioresistance is a major culprit for radiotherapy failure in esophageal squamous cell carcinoma (ESCC). This study aimed to investigate the underlying mechanism of Brd4 in radiosensitivity of ESCC. Methods Brd2/3/4 proteins were assessed in radiosensitive and radioresistant ESCC tissues using IHC. A serial of functional experiments was performed to verify the significance of Brd4 in ESCC. RNA-seq and bioinformatics analyses were used to determine the potential downstream targets. The dual-luciferase reporter and ChIP assay were further examined the underlying regulatory mechanism among targets. Besides, we further verified the importance of ATF3-mediated serine and nucleotide metabolism in radiated ESCC cells. Results Brd4 is highly expressed in radio-resistant ESCC tissue. Knockdown of Brd4 led to increased DNA damage and cell apoptosis in irradiated ESCC cells. RNA-seq analyses exhibited that ATF3 was a potential downstream target of Brd4. The dual-luciferase reporter and ChIP assay demonstrated that Brd4 upregulated ATF3 expression via activation its promoter region. Besides, we found that ATF3 could facilitate the enzyme activities involved in serine and nucleotide biosynthesis pathway to promote radiation-induced DNA damage repair. Conclusion Brd4 facilitates ATF3 expression via binding to and activating ATF3 promoter region. Enhanced ATF3 further increases crucial enzymes activity in serine and nucleotide biosynthesis pathway to promote radiation-induced DNA damage repair. Targeting Brd4 is a promising treatment strategy to improve radiosensitivity in ESCC.

Inhibiting the expression of spindle appendix cooled coil protein 1 can suppress tumor cell growth and metastasis and is associated with cancer immune cells in esophageal squamous cell carcinoma.

Inhibiting the expression of spindle appendix cooled coil protein 1 (SPDL1) can slow down disease progression and is related to poor prognosis in patients with esophageal cancer. However, the specific roles and molecular mechanisms of SPDL1 in esophageal squamous cell carcinoma (ESCC) have not been explored yet. The current study aimed to investigate the expression levels of SPDL1 in ESCC via transcriptome analysis using data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus databases. Moreover, the biological roles, molecular mechanisms, and protein networks involved in SPDL1 were identified using machine learning and bioinformatics. The cell counting kit-8 assay, EdU staining, and transwell assay were used to investigate the effects of inhibiting SPDL1 expression on ESCC cell proliferation, migration, and invasion. Finally, the correlation between the SPDL1 expression and cancer immune infiltrating cells was evaluated by analyzing data from the TCGA database. Results showed that SPDL1 was overexpressed in the ESCC tissues. The SPDL1 expression was related to age in patients with ESCC. The SPDL1 co-expressed genes included those involved in cell division, cell cycle, DNA repair and replication, cell aging, and other processes. The high-risk scores of SPDL1-related long non-coding RNAs were significantly correlated with overall survival and cancer progression in patients with ESCC (P < 0.05). Inhibiting the SPDL1 expression was effective in suppressing the proliferation, migration, and invasion of ESCC TE-1 cells (P < 0.05). The overexpression of SPDL1 was positively correlated with the levels of Th2 and T-helper cells, and was negatively correlated with the levels of plasmacytoid dendritic cells and mast cells. In conclusion, SPDL1 was overexpressed in ESCC and was associated with immune cells. Further, inhibiting the SPDL1 expression could effectively slow down cancer cell growth and migration. SPDL1 is a promising biomarker for treating patients with ESCC.

Early Diagnostic Markers for Esophageal Squamous Cell Carcinoma: Copy Number Alteration Gene Identification and cfDNA Detection

The high mortality rate of esophageal squamous cell carcinoma (ESCC) is exacerbated by the absence of early diagnostic markers. The pronounced heterogeneity of mutations in ESCC renders copy number alterations (CNAs) more prevalent among patients. The identification of CNA genes within esophageal squamous dysplasia (ESD), a precancerous stage of ESCC, is crucial for advancing early detection efforts. Utilization of liquid biopsies via droplet-based digital PCR (ddPCR) offers a novel strategy for detecting incipient tumor traces. This study undertook a thorough investigation of CNA profiles across ESCC development stages, integrating data from existing databases and prior investigations to pinpoint and confirm CNA markers conducive to early detection of ESCC. Targeted sequencing was employed to select potential early detection genes, followed by the establishment of prediction models for ESCC early detection using ddPCR. Our analysis revealed widespread CNAs during the ESD stage, mirroring the CNA landscape observed in ESCC. A total of 40 CNA genes were identified as highly frequent in both ESCC and ESD lesions, through a comprehensive gene-level CNA analysis encompassing ESD and ESCC tissues, ESCC cell lines, and pan-cancer data sets. Subsequent validation of 5 candidate markers via ddPCR underscored the efficacy of combined predictive models encompassing PIK3CA, SOX2, EGFR, MYC, and CCND1 in early ESCC screening, as evidenced by the area-under-the-curve values exceeding 0.92 (P < .0001) across various detection contexts. The findings highlighted the significant utility of CNA genes in the early screening of ESCC, presenting robust models that could facilitate early detection, broad-scale population screening, and adjunctive diagnosis.

The prognostic value of microRNA‐200 family expression in digestive system tumors: A meta‐analysis and validation

AbstractThe relevance of miR‐200 family in the prognosis of digestive system tumors remains controversial. Through a systematic review of the pertinent literature using online databases including PubMed, EMBASE, The Cochrane Library, and Web of Science, our pooled‐analysis revealed that miR‐200 family downregulation was significantly correlated with poor overall survival (OS, hazard ratio [HR] &gt; 1) and disease‐free survival (HR &gt; 1) in digestive malignancies. Consistently, subgroup analyzes of various organ tissues, univariate analysis, gastric cancer, pancreatic cancer, and patients of American descent revealed the hazardous effects of miR‐200 family downregulation. In contrast, low miR‐200 family expression in blood samples predicted favorable OS (HR &lt; 1). Moreover, lower expression levels of miR‐200c‐5p and miR‐429 were validated in esophageal squamous cell carcinoma (ESCC) tissues. Both the protein and messenger RNA expression levels of Paralemmin‐2 (PALM2) and Mitotic Arrest Deficient 2‐Like Protein (MAD2L1), regulated by miR‐200c‐5p, were notably higher in ESCC, and increased protein levels of PALM2 and MAD2L1 were correlated with adverse OS. PALM2 overexpression significantly enhanced ESCC cell migration. In conclusion, our study highlights the prognostic value of miR‐200 family in digestive system tumors, and the decrease of miR‐200c‐5p may promote ESCC invasion through upregulation of PALM2 and MAD2L1.

Identification of POU4F1 as a novel prognostic biomarker and therapeutic target in esophageal squamous cell carcinoma

BackgroundEsophageal cancer is a significant global health concern, ranking seventh in incidence and sixth in mortality. It encompasses two pathological types: esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma, with ESCC being more prevalent globally and associated with higher mortality rates. The POU (Pit-Oct-Unc) domain family transcription factors, comprising 15 members, play important roles in embryonic development and organ formation. Aberrant expression of POUs has been observed in several human cancers, influencing cell proliferation, tumor invasion, and drug resistance. However, their specific role in ESCC remains unknown.MethodsWe analyzed TCGA and GEO databases to assess POUs expression in ESCC tissues. Kaplan-Meier and ROC analyses were used to evaluate the prognostic value of POUs. Gene Set Enrichment Analysis and Protein-Protein interaction network were used to explore the potential pathway. Functional assays (Cell Counting Kit-8, EdU Staining assay, and cloning formation assay) and mechanism analyses (RNA-seq, flow cytometry, and Western blot) were conducted to determine the effects of POU4F1 knockdown on ESCC cell phenotypes and signaling pathways.ResultsPOU4F1 and POU6F2 were upregulated in various cancer tissues, including ESCC, compared to normal tissues. POU4F1 expression was significantly correlated with patient survival and superior to previous models (AUC = 0.776). Knockdown of POU4F1 inhibited ESCC cell proliferation and affected cell cycle, autophagy, and DNA damage pathways in ESCC cells.ConclusionPOU4F1 is a novel and promising prognostic and therapeutic target for ESCC patients, providing insights into potential treatment strategies.

Knockdown of WISP1/DKK1 restrains phenotypic plasticity in esophageal squamous cell carcinoma by suppressing epithelial-mesenchymal transition and stemness.

Wnt-induced signaling protein 1 (WISP1) and Dickkopf-1 (DKK1) are highly expressed in esophageal squamous cell carcinoma (ESCC), but no direct connection was identified between them. Phenotypic plasticity is a hallmark of ESCC. This research intended to identify the association between WISP1 and DKK1 and their roles in the phenotypic plasticity of ESCC. Genes differentially expressed in esophageal carcinoma were analyzed in the GEO database, followed by analyses of GO and KEGG enrichment to screen the hub gene. WISP1 expression and DKK1 secretion was assessed in ESCC tissues and cells. The tumor xenograft and in vivo metastasis models were established by injecting ESCC cells into nude mice. Functional deficiency and rescue experiments were conducted, followed by assays for cell proliferation, migration/invasion, stemness, epithelial-mesenchymal transition (EMT), and apoptosis, as well as tumor volume, weight, proliferation, stemness, and lung metastasis. The binding relationship and co-expression of WISP1 and DKK1 were determined. WISP1 and DKK1 were upregulated in ESCC cells and tissues, and WISP1 was enriched in the cell stemness and Wnt pathways. WISP1 knockdown subdued proliferation, migration/invasion, EMT activity, and stemness but enhanced apoptosis in ESCC cells. WISP1 knockdown restrained ESCC growth, proliferation, stemness, and metastasis in vivo. WISP1 bound to DKK1 in ESCC. DKK1 overexpression abolished the repressive impacts of WISP1 knockdown on the malignant behaviors of ESCC cells in vitro and of ESCC tumor in vivo. Knockdown of WISP1/DKK1 restrains the phenotypic plasticity in esophageal squamous cell carcinoma by suppressing epithelial-mesenchymal transition and stemness.

Targeting and degradation of OTUB1 by Erianin for antimetastasis in esophageal squamous cell carcinoma

BackgroundMetastasis is a major contributor to mortality in patients with esophageal squamous cell carcinoma (ESCC); effective treatment is currently lacking. Erianin, a bioactive ingredient of traditional Chinese medicine, Dendrobium chrysotoxum, has anti-tumor activity against multiple human tumors. However, the effect and associated underlying mechanism of Erianin on ESCC antimetastasis remain unclear. PurposeTo investigate the anti-metastatic properties of Erianin in ESCC both in vitro and in vivo and associated molecular mechanisms. MethodsWound healing assay, Transwell assay, CCK-8 assay, immunohistochemistry, and lung metastasis mouse model were carried out to examine ESCC cell migration and viability in vitro and in vivo. Drug affinity responsive target stability (DARTS), cellular thermal migration assay (CETSA), molecular docking, and Surface plasmon resonance (SPR) assay were used to confirm Erianin binding to ovarian tumor ubiquitin aldehyde-binding protein 1 (OTUB1) protein. Protein stability assay, cell transfection, and western blotting were used to confirm Erianin-mediated degradation of OTUB1 and Snail via the ubiquitin-proteasome pathway. qRT-PCR and western blotting were used to assess OTUB1expression in ESCC tissues. ResultsErianin suppressed the migration/invasion of ESCC cells without modulating cell viability in vitro and in vivo, bound to OTUB1 through DARTS, CETSA, and molecular docking, and SPR assay, and enhanced OTUB1 degradation via the ubiquitin-proteasome system. Moreover, Erianin inhibited the ESCC epithelial–mesenchymal transition by enhancing the ubiquitination and degradation of Snail via targeting OTUB1. ConclusionErianin inhibited ESCC metastasis through ubiquitination and degradation of Snail via targeting OTUB1. Our findings suggest Erianin as a novel OTUB1 inhibitor for preventing ESCC metastasis.

Ribonucleotide reductase small subunit M2 promotes the proliferation of esophageal squamous cell carcinoma cells via HuR-mediated mRNA stabilization

Esophageal squamous cell carcinoma (ESCC), a malignancy of the digestive system, is highly prevalent and the primary cause of cancer-related deaths worldwide due to the lack of early diagnostic biomarkers and effective therapeutic targets. Dysregulated ribonucleotide reductase (RNR) expression has been confirmed to be causally linked to tumorigenesis. This study demonstrated that ribonucleotide reductase small subunit M2 (RRM2) is significantly upregulated in ESCC tissue and that its expression is negatively correlated with clinical outcomes. Mechanistically, HuR promotes RRM2 mRNA stabilization by binding to the adenine/uridine (AU)-rich elements (AREs) within the 3′UTR, resulting in persistent overexpression of RRM2. Furthermore, bifonazole is identified as an inhibitor of HuR via computational screening and molecular docking analysis. Bifonazole disrupts HuR-ARE interactions by competitively binding to HuR at F65, R97, I103, and R153 residues, resulting in reduced RRM2 expression. Furthermore, bifonazole exhibited antitumor effects on ESCC patient-derived xenograft (PDX) models by decreasing RRM2 expression and the dNTP pool. In summary, this study reveals the interaction network among HuR, RRM2, and bifonazole and demonstrated that bifonazole is a potential therapeutic compound for ESCC through inhibition of the HuR/RRM2 axis.

Synaptotagmin 13 Could Drive the Progression of Esophageal Squamous Cell Carcinoma Through Upregulating ACRV1.

SYT13 is one of the atypical members of the synaptotagmin (SYT) family whose function has attracted considerable attention in recent years. Although SYT13 has been studied in several types of human cancers, such as lung cancer, its role in esophageal squamous cell carcinoma (ESCC) is still unclear. It was demonstrated that SYT13 is significantly upregulated in ESCC tissues compared with normal ones and correlated with higher degree of malignancy. Knockdown of SYT13 could inhibit ESCC cell proliferation and migration, while promoting cell apoptosis. Meanwhile, ESCC cells with relatively lower SYT13 expression grew slower invivo and finally formed smaller xenografts. Furthermore, acrosomal vesicular protein 1 was identified as a potential downstream target of SYT13, which regulates cell phenotypes of ESCC cells in cooperation with SYT13. All the in vitro and invivo results in this study identified that SYT13 silencing could be an effective strategy to inhibit the development of ESCC, which could be considered as a promising therapeutic target in the treatment of ESCC.

Ferroptosis suppressor genes are highly expressed in esophageal cancer to inhibit tumor cell ferroptosis

To explore the role of ferroptosis-related genes in regulating ferroptosis of esophageal squamous cell carcinoma (ESCC). ESCC datasets GSE161533 and GSE20347 were downloaded from the Gene Expression Omnibus (GEO) to identify the differentially expressed genes (DEGs) using R software. ESCC ferroptosis-related genes obtained by intersecting the DEGs with ferroptosis-related genes from FerrDb were analyzed using GO and KEGG analyses, protein-protein interaction (PPI) network analysis, and core gene identification through Cytoscape. The identified ferroptosis suppressor genes were validated using TCGA database, and their expression levels were detected using RT-qPCR in cultured normal esophageal cells and ESCC cells. Six ferroptosis suppressor genes (RRM2, GCLC, TFRC, TXN, SLC7A11, and EZH2) were downregulated with siRNA in ESCC cells, and the changes in cell proliferation and apoptosis were assessed with CCK8 assay and flow cytometry; Western blotting was performed to examine the changes in ferroptosis progression of the cells. We identified a total of 58 ESCC ferroptosis-related genes, which involved such biological processes as glutathione transmembrane transport, iron ion transport, and apoptosis and the ferroptosis, glutathione metabolism, and antifolate resistance pathways. The PPI network included 54 nodes and 74 edges with a clustering coefficient of 0.522 and PPI enrichment P<0.001. Cytoscape identified 6 core ferroptosis suppressor genes (RRM2, TFRC, TXN, EZH2, SLC7A11, and GCLC), which were highly expressed in ESCC tissues in the TCGA dataset and in ESCC cell lines. Downregulating these genes in ESCC TE1 cells significantly inhibited cell proliferation, promoted cell apoptosis, reduced the expression levels of ferroptosis markers GPX4 and FIH1, and increased the expression of ACSL4. High expression of ferroptosis suppressor genes in ESCC may cause arrest of ferroptosis progression to facilitate tumor development, and inhibiting these genes can restore ferroptosis and promote cell apoptosis, suggesting their value as potential therapeutic targets for ESCC.

Suppressing SENP1 inhibits esophageal squamous carcinoma cell growth via SIRT6 SUMOylation.

Esophageal squamous cell carcinoma (ESCC) is a prevalent tumor in the gastrointestinal tract, but our understanding of the molecular mechanisms underlying ESCC remains incomplete. Existing studies indicate that SUMO specific peptidase 1 (SENP1) plays a crucial role in the development and progression of various malignant tumors through diverse molecular mechanisms. However, the functional mechanism and clinical implications of SENP1 in the progression of ESCC remain unclear. Bulk RNA-Sequencing (RNA-seq) was used to compare potential genes in the esophageal tissues of mice with ESCC to the control group. The up-regulated SENP1 was selected. The protein level of SENP1 in ESCC patient samples was analyzed by immunohistochemistry and western blot. The potential prognostic value of SENP1 on overall survival of ESCC patients was examined using tissue microarray analysis and the Kaplan-Meier method. The biological function was confirmed through in vitro and in vivo knockdown approaches of SENP1. The role of SENP1 in cell cycle progression and apoptosis of ESCC cells was analyzed by flow cytometry and western blot. The downstream signaling pathways regulated by SENP1 were investigated via using RNA-Seq. SENP1-associated proteins were identified through immunoprecipitation. Overexpression of Sirtuin 6 (SIRT6) wildtype and mutant was performed to investigate the regulatory role of SENP1 in ESCC progression in vitro. Our study discovered that SENP1 was upregulated in ESCC tissues and served as a novel prognostic factor. Moreover, SENP1 enhanced cell proliferation and migration of ESCC cell lines in vitro, as well as promoted tumor growth in vivo. Thymidine kinase 1 (TK1), Geminin (GMNN), cyclin dependent kinase 1(CDK1), and cyclin A2 (CCNA2) were identified as downstream genes of SENP1. Mechanistically, SENP1 deSUMOylated SIRT6 and subsequently inhibited SIRT6-mediated histone 3 lysine 56 (H3K56) deacetylation on those downstream genes. SIRT6 SUMOylation mutant (4KR) rescued the growth inhibition upon SENP1 depletion. SENP1 promotes the malignant progression of ESCC by inhibiting the deacetylase activity of SIRT6 pathway through deSUMOylation. Our findings suggest that SENP1 may serve as a valuable biomarker for prognosis and a target for therapeutic intervention in ESCC.

Combination of high anti-SKI and low anti-TMED5 antibody levels is preferable prognostic factor in esophageal carcinoma.

Given that esophageal cancer is highly malignant, the discovery of novel prognostic markers is eagerly awaited. We performed serological identification of antigens by recombinant cDNA expression cloning (SEREX) and identified SKI proto-oncogene protein and transmembrane p24 trafficking protein 5 (TMED5) as antigens recognized by serum IgG antibodies in patients with esophageal carcinoma. SKI and TMED5 proteins were expressed in Escherichia coli, purified by affinity chromatography, and used as antigens. The serum anti-SKI antibody (s-SKI-Ab) and anti-TMED5 antibody (s-TMED5-Ab) levels were significantly higher in 192 patients with esophageal carcinoma than in 96 healthy donors. The presence of s-SKI-Abs and s-TMED5-Abs in the patients' sera was confirmed by western blotting. Immunohistochemical staining showed that the TMED5 protein was highly expressed in the cytoplasm and nuclear compartments of the esophageal squamous cell carcinoma tissues, whereas the SKI protein was localized predominantly in the nuclei. Regarding the overall survival in 91 patients who underwent radical surgery, the s-SKI-Ab-positive and s-TMED5-Ab-negative statuses were significantly associated with a favorable prognosis. Additionally, the combination of s-SKI-Ab-positive and s-TMED5-Ab-negative cases showed an even clearer difference in overall survival as compared with that of s-SKI-Ab-negative and s-TMED5-Ab-positive cases. The s-SKI-Ab and s-TMED5-Ab biomarkers are useful for diagnosing esophageal carcinoma and distinguishing between favorable and poor prognoses.

Porphyromonas gingivalis infection facilitates immune escape of esophageal cancer by enhancing YTHDF2-mediated Fas degradation

To investigate the effect of Porphyromonas gingivalis (Pg) infection on immune escape of oesophageal cancer cells and the role of YTHDF2 and Fas in this regulatory mechanism. We examined YTHDF2 and Fas protein expressions in esophageal squamous cell carcinoma (ESCC) tissues with and without Pg infection using immunohistochemistry and in Pg-infected KYSE150 cells using Western blotting. The interaction between YTHDF2 and Fas was investigated by co-immunoprecipitation (Co-IP). Pg-infected KYSE150 cells with lentivirus-mediated YTHDF2 knockdown were examined for changes in expression levels of YTHDF2, cathepsin B (CTSB), Fas and FasL proteins, and the effect of E64 (a cathepsin inhibitor) on these proteins were observed. After Pg infection and E64 treatment, KYSE150 cells were co-cultured with human peripheral blood mononuclear cells (PBMCs), and the expressions of T cell-related effector molecules were detected by flow cytometry. ESCC tissues and cells with Pg infection showed significantly increased YTHDF2 expression and lowered Fas expression. The results of Co-IP demonstrated a direct interaction between YTHDF2 and Fas. In Pg-infected KYSE150 cells with YTHDF2 knockdown, the expression of CTSB was significantly reduced while Fas and FasL expressions were significantly increased. E64 treatment of KYSE150 cells significantly decreased the expression of CTSB without affecting YTHDF2 expression and obviously increased Fas and FasL expressions. Flow cytometry showed that in Pg-infected KYSE150 cells co-cultured with PBMCs, the expressions of Granzyme B and Ki67 were significantly decreased while PD-1 expression was significantly enhanced. Pg infection YTHDF2-dependently regulates the expression of Fas to facilitate immune escape of esophageal cancer and thus promoting cancer progression, suggesting the key role of YTHDF2 in regulating immune escape of esophageal cancer.

High expression of the stemness-associated molecule Nanog in esophageal squamous cell carcinoma tissues promotes tumor invasion and metastasis by activating the TGF-β signaling pathway

To investigate the expression of Nanog and its regulatory relationship with MMP-2/MMP-9 proteins in esophageal squamous cell carcinoma (ESCC). We detected Nanog and MMP-2/MMP-9 protein expressions in 127 ESCC tissues and 82 adjacent normal tissues using immunohistochemistry and explored their correlations with the clinicopathological parameters and prognosis of the patients. GEO database was utilized to analyze the pathways enriched with the stemness-related molecules including Nanog, and TIMER online tool was used to analyze the correlations among TβR1, MMP-2, and MMP-9 in esophageal cancer. Nanog and MMP-2/MMP-9 proteins were significantly upregulated in ESCC tissues and positively intercorrelated. Their expression levels were closely correlated with infiltration depth and lymph node metastasis of ESCC but not with age, gender, or tumor differentiation. The patients with high expressions of Nanog and MMP-2/MMP-9 had significantly shorter survival time. Bioinformatics analysis showed enrichment of stemness-associated molecules in the TGF-β signaling pathway, and the expressions of MMP-2/MMP-9 and TβR1 were positively correlated. In cultured ESCC cells, Nanog knockdown significantly decreased the expression of TβR1, p-Smad2/3, MMP-2, and MMP-9 and strongly inhibited cell migration. The high expressions of Nanog, MMP-2, and MMP-9, which are positively correlated, are closely related with invasion depth, lymph node metastasis, and prognosis of ESCC. Nanog regulates the expressions of MMP-2/MMP-9 proteins through the TGF-β signaling pathway, and its high expression promotes migration of ESCC cells.

Vimentin, inversely correlating with infiltration of CD8 + T lymphocytes, promotes nuclear translocation of PD-L1 in esophageal squamous cell carcinoma

Vimentin has been considered a canonical marker of epithelial-mesenchymal transition (EMT) and is associated with tumor escape characterized by aberrant PD-L1 expression. However, whether there is a relationship between vimentin and PD-L1 in esophageal squamous cell carcinoma (ESCC) remains poorly understood. The immunological involvement of vimentin in ESCC was first analyzed by multiplex immunofluorescence staining in ESCC tissue microarray followed by a xenografted mouse model. In vivo, C57BL/6 mice were subcutaneously transplanted with AKR cells after stable silencing of vimentin. In vivo results showed that in addition to PD-L1 and PD-L2 expression, vimentin expression was inversely correlated with CD8+ T-cell infiltration. Mechanistically, vimentin can directly interact with PD-L1 and promote nuclear translocation of PD-L1 in AKR cells. In addition, SEMA6C, STC-2 and TRAILR2 were identified as cytokines modulated by vimentin. Blockade of STC-2 and TRAILR2 in co-culture with their own primary antibodies was shown to recruit more CD8+ T cells than controls. Together, these data strongly suggest targeting Vimenin to overcome the immune cycle in ESCC.

IQGAP1 overexpression attenuates chemosensitivity through YAP-mediated ferroptosis inhibition in esophageal squamous cell cancer cells

Chemoresistance is one of the major hindrances to many cancer therapies, including esophageal squamous cell carcinoma (ESCC). Ferroptosis, a new programmed cell death, plays an essential role in chemoresistance. IQ-domain GTPase activating protein 1 (IQGAP1) is a scaffold protein and functions as an oncogene in various human malignancies. However, the underlying effect and molecular mechanisms of IQGAP1 on paclitaxel (PTX) resistance and ferroptosis in ESCC remain to be elucidated. In this study, we found that IQGAP1 was highly expressed in ESCC tissues and could as a potential biomarker for diagnosis and predicting the prognosis of ESCC. Functional studies revealed that IQGAP1 overexpression reduced the sensitivity of ESCC cells to PTX by enhancing ESCC cell viability and proliferation and inhibiting cell death, and protected ESCC cells from ferroptosis, whereas IQGAP1 knockdown exhibited contrary effects. Importantly, reductions of chemosensitivity and ferroptosis caused by IQGAP1 overexpression were reversed with ferroptosis inducer RSL3, while the increases of chemosensitivity and ferroptosis caused by IQGAP1 knockdown were reversed with ferroptosis inhibitor ferrostatin-1 (Fer-1) in ESCC cells, indicating that IQGAP1 played a key role in resistance to PTX through regulating ferroptosis. Mechanistically, we demonstrated that IQGAP1 overexpression upregulated the expression of Yes-associated protein (YAP), the central mediator of the Hippo pathway. YAP inhibitor Verteporfin (VP) could reverse the effects of IQGAP1 overexpression on ESCC chemoresistance and ferroptosis. Taken together, our findings suggest that IQGAP1 promotes chemoresistance by blocking ferroptosis through targeting YAP. IQGAP1 may be a novel therapeutic target for overcoming chemoresistance in ESCC.