Esophageal Squamous Cell Carcinoma Cell Lines Research Articles

Interleukin 13 participates in terminal differentiation of esophageal squamous cell carcinoma cells.

BackgroundIn China, esophageal squamous cell carcinoma (ESCC) accounts for more than 90% of all esophageal cancer cases. Interleukin 13 (IL-13) was widely reported to play a key role in tumor progression. Our previous study reported that IL-13 was a favorable predictive marker for the overall survival of esophageal squamous cell carcinoma (ESCC) patients, but how IL-13 contributes to ESCC progression remains unknown. This study aims to explore the role of IL-13 and its underlying downstream molecular mechanisms in ESCC progression.MethodsTissue microarrays including 262 primary ESCC tumor tissues were collected and analyzed. The expression of IL-13 in ESCC tumor tissue was detected with immunohistochemistry staining (IHC). Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to qualify the expressions of KRT13, KRT4 and 15-lipoxygenase-1 (15-LOX-1) in cultured ESCC cell lines with recombinant IL-13 treatment.ResultsIL-13 was expressed in the esophageal epithelium cells and ESCC tumor cells. High IL-13 expression in ESCC tumor cells predicted a good prognosis for patients. Recombinant human IL-13 raised KRT13 and 15-LOX-1 mRNA levels, but lowered KRT4 mRNA level 15-LOX-1 in ESCC cells in vitro.ConclusionsIn summary, our study suggests that IL-13 might improve the prognosis of ESCC by promoting the terminal differentiation of ESCC cells. This may offer potential new therapeutic target for early treatment of ESCC.

Exosomal MicroRNA Analyses in Esophageal Squamous Cell Carcinoma Cell Lines.

Exosomal miRNAs have been studied in various cancers as minimally invasive biomarkers. This study aimed to investigate the potential of exosomal microRNAs (miRNAs) as biomarkers for esophageal squamous cell carcinoma (ESCC). Exosomes were isolated from cultures of esophageal epithelial cell and ESCC cell lines using ExoDisc, and exosomal miRNAs were detected via miRNA sequencing. Of the differentially expressed 14 miRNAs, the top 2 up-regulated miRNAs (miR-205-5p and miR-429) and top 2 down-regulated miRNAs (miR-375-3p and miR-483-3p) were selected as ESCC target miRNAs. Four selected exosomal miRNAs were validated in the plasma of 20 healthy controls (HCs) and 40 ESCC patients via quantitative reverse transcription-polymerase chain reaction. The expression of plasma exosomal miR-205-5p and miR-429 significantly increased, while that of plasma exosomal miR-375-3p was significantly reduced in ESCC patients compared to that in HCs. At cut-off values of 5.04, 2.564, and 0.136, the sensitivity and specificity for the diagnosis of ESCC were 72.5% and 70.0% for miR-205-5p, 60.0% and 60.0% for miR-429, and 65.0% and 65.0% for miR-375-3p, respectively. Based on the exosomal miRNAs identified in ESCC cell lines, our study demonstrated that plasma exosomal miR-205-5p, miR-429, and miR-375-3p could serve as potential biomarkers for ESCC diagnosis.

COQ10B Knockdown Modulates Cell Proliferation, Invasion, Migration, and Apoptosis in Esophageal Squamous Cell Carcinoma.

Objective Esophageal squamous-cell carcinoma (ESCC) is an aggressive malignant tumor, accounting for more than 90% of esophageal cancers. However, treatments such as surgical resection, radiotherapy, and chemotherapy are unable to achieve ideal clinical outcomes. The purpose of this study was to explore the effects of COQ10B on proliferation, apoptosis, migration, and invasion of esophageal squamous-cell carcinoma (ESCC) cells. Methods Quantitative real-time PCR (qRT-PCR) was used to detect the expression of COQ10B in ESCC and normal tissues and in ESCC cell lines (KYSE-150 and TE-1). MTT assay and flow cytometry were applied to investigate the effects of COQ10B shRNA lentivirus (LV-shCOQ10B) on ESCC cell proliferation and apoptosis, respectively. The effect of COQ10B silencing on ESCC cell migration and invasion was determined by wound healing assay and transwell invasion assay, respectively. Results The expression of COQ10B mRNA in ESCC tissues was higher than that in surrounding tissues. The decreased COQ10B level in KYSE-150 and TE-1 cells by LV-shCOQ10B could inhibit cell proliferation, promote cell apoptosis, and reduce the ability of invasion and migration (all P < 0.05). Conclusion COQ10B was highly expressed in human ESCC tissues. COQ10B silencing contributed to the inhibition of proliferation, invasion, and migration of ESCC cells and the promotion of cell apoptosis, suggesting COQ10B may be a potential molecular target for the diagnosis and treatment of ESCC.

KDM2A plays a dual role in regulating the expression of malignancy-related genes in esophageal squamous cell carcinoma

KDM2A is a histone demethylase, which primarily catalyzes the demethylation of H3K36me2. Abnormal expression of KDM2A is observed in many types of cancers; however, the molecular events connected to KDM2A expression remain unclear. We report that KDM2A performs an oncogenic function in esophageal squamous cell carcinoma (ESCC) and is robustly expressed in ESCC cells. ShRNA-mediated knockdown of KDM2A resulted in a significant inhibition of the malignant phenotype of ESCC cell lines, whereas ectopic expression of KDM2A showed the opposite effect. We also analyzed the function of KDM2A using a CRISPR-CAS9 depletion system and subsequent rescue experiment, which also indicated a cancerous role of KDM2A. Interestingly, analysis of the gene expression network controlled by KDM2A using RNA-seq revealed an unexpected feature: KDM2A could induce expression of a set of well-documented oncogenic genes, including IL6 and LAT2, while simultaneously suppressing another set of oncogenes, including MAT2A and HMGCS1. Targeted inhibition of the upregulated oncogene in the KDM2A-depleted cells led to a synergistic suppressive effect on the malignant phenotype of ESCC cells. Our results revealed the dual role of KDM2A in ESCC cells, which may have therapeutic implications.

Raman spectroscopy and machine learning for the classification of esophageal squamous carcinoma

Early diagnosis of esophageal squamous cell carcinoma (ESCC), a common malignant tumor with a low overall survival rate due to metastasis and recurrence, is critical for effective treatment and improved prognosis. Raman spectroscopy, an advanced detection technology for esophageal cancer, was developed to improve diagnosis sensitivity, specificity, and accuracy. This study proposed a novel, effective, and noninvasive Raman spectroscopy technique to differentiate and classify ESCC cell lines. Seven ESCC cell lines and tissues of an ESCC patient with staging of T3N1M0 and T3N2M0 at low and high differentiation levels were investigated through Raman spectroscopy. Raman spectral data analysis was performed with four machine learning algorithms, namely principal components analysis (PCA)– linear discriminant analysis (LDA), PCA–eXtreme gradient boosting (XGB), PCA– support vector machine (SVM), and PCA– (LDA, XGB, SVM)-stacked Gradient Boosting Machine (GBM). Four machine learning algorithms were able to classifiy ESCC cell subtypes from normal esophageal cells. The PCA–XGB model achieved an overall predictive accuracy of 85% for classifying ESCC and adjacent tissues. Moreover, an overall predictive accuracy of 90.3% was achieved in distinguishing low differentiation and high differentiation ESCC tissues with the same stage when PCA–LDA, XGM, and SVM models were combined. This study illustrated the Raman spectral traits of ESCC cell lines and esophageal tissues related to clinical pathological diagnosis. Future studies should investigate the role of Raman spectral features in ESCC pathogenesis.

OTUB2 Regulates YAP1/TAZ to Promotes the Progression of Esophageal Squamous Cell Carcinoma

ObjectiveThe effects of Otubain-2 (OTUB2) on the proliferation, invasion, and migration of esophageal squamous cell carcinoma (ESCC) were investigated by interfering with OTUB2 expression.MethodsBioinformatics analysis was used to analyze OTUB2 expression in esophageal carcinoma and interactions between OTUB2 and YAP1/TAZ. Paraffin-embedded ESCC tissues (n = 183) were selected for immunohistochemical staining to detect OTUB2, YAP1, TAZ, CTGF and their relationship with clinicopathological parameters, then the survival prognosis of ESCC patients was analyzed. Immunofluorescence, western blotting, and qRT-PCR were used to evaluate OTUB2 in ESCC cell lines. Cell lines with the highest expression of OTUB2 were transfected with lentivirus to knockdown OTUB2 levels. Changes in KYSE150 cell proliferation, migration, and invasion were measured using CCK-8, wound healing, and clone formation assays. The Transwell test and flow cytometry identified OTUB2 targets and explored roles and mechanisms involved in ESCC. Effects of OTUB2 on YAP1/TAZ signaling were also observed.ResultsBioinformatics analysis revealed OTUB2 was highly expressed in esophageal cancer and was associated with YAP1/TAZ. Immunohistochemistry showed that OTUB2 expression was increased in ESCC samples compared to parcancerous tissue. YAP1 and TAZ were higher expression in ESCC tissues, mainly localized in the nucleus. Compared with controls, the proliferation, migration, and invasion ability of KYSE150 cells after OTUB2 knockdown were significantly reduced (P < 0.05). The protein expression levels of YAP1, TAZ and CTGF decreased after knocking down the expression of OTUB2 (P < 0.05). OTUB2 knockdown in ESCC cell lines suppressed YAP1/TAZ signaling.ConclusionsOTUB2 regulated the protein expression of YAP1/TAZ to promote cell proliferation, migration, invasion, and tumor development. Therefore, OTUB2 may represent a biomarker for ESCC and a potential target for ESCC treatment.

The abnormal expression of circ-ARAP2 promotes ESCC progression through regulating miR-761/FOXM1 axis-mediated stemness and the endothelial–mesenchymal transition

Circular RNAs (circRNAs) belong to a novel class of noncoding RNA that gained more attention in human cancer pathogenesis. The role of circRNA in esophageal squamous cell carcinoma (ESCC) is largely unclear. Present investigation was to characterize new circRNAs regulating ESCC progression and explore the regulatory mechanisms in ESCC. In this study, circRNAs differentially expressed in ESCC and adjacent normal tissues were characterized via high-throughput sequencing. Then the differentially expressed circRNA between ESCC and adjacent normal tissues were investigated using Rt-qPCR. The role of circ-ARAP2 expression on tumor progression were detected in both in vivo and in vitro. Luciferase reporter assays were used to identify the relationships among circ-ARAP2, microRNA (miR)-761 and the cell cycle regulator Forkhead Box M1 (FOXM1). The result of the expression profile analyses regarding human circRNAs in ESCC demonstrated that circ-ARAP2 was up-regulated significantly in both ESCC tissues and cell lines. Downregulation circ-ARAP2 suppressed ESCC proliferation, tumor growth and metastasis in both in vivo and in vitro. The data also suggested that miR-761 and FOXM1 were circ-ARAP2 downstream targets which were confirmed through luciferase reporter analysis. Overexpression of FOXM1 or inhibiting miR-761 restored ESCC cell proliferation and invasion ability after silencing circ-ARAP2. The study also found that circ-ARAP2 influenced the endothelial–mesenchymal transition (EMT) and cancer stem cells differently by regulating miR-761/FOXM1. In one word, the results demonstrated that abnormal circ-ARAP2 expression promoted ESCC progression by regulating miR-761/FOXM1 axis-mediated stemness and EMT.

Targeting stearoyl-coa desaturase enhances radiation induced ferroptosis and immunogenic cell death in esophageal squamous cell carcinoma

ABSTRACT Overcoming resistance to radiation is a major challenge in cancer treatment. Stearoyl-coa desaturase (SCD1) is the enzyme responsible for oleic acid (OA) and palmitoleic acid (POA) formation. Here, we provided evidence that targeting SCD1 was capable of inducing ferroptosis and immunogenic cell death (ICD), thereby improving the radiation sensitivity of esophageal squamous cell carcinoma (ESCC). ESCC cell lines with high SCD1 expression were treated with MF-438 (SCD1 inhibitor) to determine cell viability. Colony formation assay was performed to evaluate the radiation sensitization of SCD1 inhibitor. Tumor cell ferroptosis and ICD was analyzed in MF-438, radiation therapy (RT) and the combination treatment group. The potential molecular mechanisms underlying MF-438 as a novel radiation sensitizer in ESCC were explored. We concluded by assessing SCD1 as a prognostic factor in ESCC. MF-438 exhibited antitumor activity in ESCC cells. Our outcomes revealed significant improvement of radiation sensitivity by MF-438. Moreover, the combination treatment enhanced tumor cell ferroptosis and ICD. Further analyses revealed SCD1 conferred radiation resistance via alleviating ferroptosis in tumor cells; targeting SCD1 inhibited the biosynthesis of OA and POA, and improved radiation induced ferroptosis in ESCC cells. Clinical analysis indicated high expression of SCD1 was associated with unfavorable survival in patients of ESCC. In summary, our results demonstrated that MF-438 acted as a ferroptosis inducer. Targeting SCD1 conferred the immunogenicity of ferroptotic cancer cells and increased the effectiveness of RT in ESCC. SCD1 could be considered as a useful prognostic indicator of survival in ESCC.

CircLONP2 Accelerates Esophageal Squamous Cell Carcinoma Progression via Direct MiR-27b-3p-ZEB1 Axis.

Circular RNAs (circRNAs) are important mediators in esophageal squamous cell carcinoma (ESCC) carcinogenesis. We aim to explore the functions and mechanisms of circLONP2 in ESCC progression. The circLONP2 level was evaluated in ESCC samples and cell lines. The role and mechanisms of circLONP2 in ESCC proliferation and migration were demonstrated in vitro. We found that circLONP2 was upregulated in human ESCC and predicts poor overall survival (OS) and disease-free survival (DFS). CircLONP2 promotes ESCC aggressiveness by directly interacting with miR-27b-3p, thus upregulating the expression levels of its target gene ZEB1 by suppressing miR-27b-3p activity. Therefore, we demonstrated that circLONP2/miR-27b-3p/ZEB1 axis promotes ESCC metastasis via regulating epithelial-to-mesenchymal transition (EMT)-related proteins. CircLONP2 may serve as an oncogenic circRNA and as a prognostic biomarker in ESCC progression.

C12orf59 Promotes Esophageal Squamous Cell Carcinoma Progression via YAP-Mediated Epithelial-Mesenchymal Transition.

C12orf59 is a novel gene widely expressed in diverse normal human tissues. Aberrant expression of C12orf59, which is involved in tumor progression, has been reported in a few types of cancer. However, its expression and biological function in esophageal squamous cell carcinoma (ESCC) remain largely unclear. Here, we found that the mRNA and protein levels of C12orf59 were prominently higher in both tumor tissues and most ESCC cell lines. Functionally, C12orf59 overexpression promoted ESCC cell proliferation, migration and invasion, whereas C12orf59 depletion worked oppositely. Mechanistically, C12orf59 exerted its oncogenic function through the induction of epithelial-mesenchymal transition (EMT) of ESCC cells, which relied on Yes-associated protein (YAP) dephosphorylation and nuclear translocation. Constitutively active YAP further facilitated cell migration, invasion and EMT induced by enforced C12orf59 overexpression. On the contrary, increased cell motility and EMT caused by enforced C12orf59 overexpression were dramatically repressed upon YAP inactivation by verteporfin. Thus, we conclude that YAP activation driven by C12orf59 contributes to the malignancy of ESCC through EMT and that targeting drugs for C12orf59 combined with YAP inhibitor may be a potential therapeutic strategy for ESCC.

Chlorogenic Acid Inhibition of Esophageal Squamous Cell Carcinoma Metastasis via EGFR/p-Akt/Snail Signaling Pathways

Chlorogenic acid (CGA) is a polyphenol compound found in a variety of foods, including coffee, tea, cherries, and apples. It has been found by a number of studies to affect the viability of human cancer cells. No study has investigated its effect on esophageal squamous cell carcinoma (ESCC) metastasis or the molecular mechanism underlying its effect on this disease. We first used the Taiwanese ESCC cell line CE81T/VGH to create CE81T-M4 cells. Treatment of higher motility cells with chlorogenic acid for 24 h led to inhibition of cell migration and invasion as shown by scratch migration and transwell assays. Western blotting showed that chlorogenic acid halted the activation of EGFR/p-Akt/Snail pathway and suppressed the expression of MMP-2 and MMP-9. Knockdown of either EGFR or Akt inhibited Snail, MMP2, and MMP9 activity as well as cell migration and invasion. Chlorogenic acid inhibited cancer cell motility via the EGFR/p-Akt/Snail pathway and could potentially be used to develop an antimetastatic agent for ESCC in the future.

Circ_0000705 facilitates proline metabolism of esophageal squamous cell carcinoma cells by targeting miR-621/PYCR1 axis

CircRNAs have been found to play crucial roles in the metabolism and progression of cancers, but their roles and mechanisms in esophageal squamous cell carcinoma (ESCC) have not been fully elucidated. This work is aimed to explore the role and mechanism of hsa_circ_0000705 (circ_0000705) in ESCC. Circ_0000705 expression was up-regulated in ESCC tissues and cell lines, and high circ_0000705 expression was correlated with poor survival. Circ_0000705 facilitated cell proliferation, invasion, migration and proline metabolism of ESCC cells. The inhibitory effects of circ_0000705 knockdown on cell invasion, migration and proline metabolism were partly rescued by miR-621 inhibition or PYCR1 over-expression. Furthermore, circ_0000705 expression is negatively correlated with miR-621 expression, and positively correlated with PYCR1 in ESCC tissues. Mechanistically, circ_0000705 acted as a ceRNA by sponging miR-621, thereby facilitating PYCR1 expression in ESCC cells. In conclusion, circ_0000705 promoted proline metabolism and malignant progression of ESCC by regulating the miR‑621/PYCR1 axis.

Silencing of integrin subunit α3 inhibits the proliferation, invasion, migration and autophagy of esophageal squamous cell carcinoma cells.

Esophageal squamous cell carcinoma (ESCC) is a deadly disease that seriously affects global public health. The aim of the present study was to explore the role of integrin subunit α3 (ITGA3) in ESCC and investigate its detailed molecular mechanisms. Using reverse transcription–quantitative PCR (RT-qPCR) and western blotting, the mRNA and protein expression of ITGA3 in cell lines was detected. In addition, a series of cellular biological experiments, including Cell Counting Kit-8, wound-healing, Transwell and TUNEL assays, were used to evaluate proliferation, migration, invasion and apoptosis, respectively. Furthermore, western blotting was used to measure the expression of corresponding proteins. ITGA3 was found to be upregulated in ESCC cell lines (ECA109 and TE1). It was also found that ITGA3 silencing inhibited the proliferation, migration, invasion and autophagy of ECA109 and TE1 cells but promoted their apoptosis. In addition, ITGA3 silencing was found to inhibit the FAK/PI3K/AKT signaling pathway. In conclusion, ITGA3 knockdown suppressed cell proliferation, invasion, migration and autophagy in ECA109 and TE1 cells, suggesting that ITGA3 may be a potential therapeutic target for the treatment of ESCC.

Abstract 723: Dual inhibition of MDM2 and p38 MAPK signaling is a potential therapeutic strategy in esophageal squamous cell carcinoma

Abstract Background: Esophageal squamous cell carcinoma (ESCC) is one of the most common lethal malignancies. Despite recent advances in treatment, the overall 5-year survival rate remains low, primarily due to late diagnosis, acquired resistance to therapy, and distant metastases. Hence, development of novel therapeutic strategies is required to improve patient outcomes. The MDM2 gene is amplified in some patients with ESCC, frequently decreasing the tumor suppressive function of p53. In addition, 40-60% of ESCC tumors exhibit p53 mutations. Missense mutations within the p53 gene cause its overexpression and subsequent activation of p38 MAPK signaling. In this study, we aimed to investigate the effect of combining a p38 MAPK inhibitor and an MDM2 antagonist as a potential therapeutic strategy in ESCC. Methods: To determine the synergistic anti-tumor activity of the MDM2 antagonist siremadlin (HDM-201) and the p38 MAPK inhibitor Ralimetinib dimesylate (LY2228820), we performed cell viability, colony formation, apoptosis, and cell cycle analysis in ESCC cell lines. Next, we evaluated the anti-tumor activity of HDM-201 and LY2228820 in a xenograft mouse model. Finally, we performed siRNA mediated silencing of p53 to assess its functional role in the MDM2 antagonist-induced activation of p38 MAPK signaling and its ability to modulate the DNA damage response (DDR) by measuring ROS status and phosphorylation of H2AX. Results: HDM-201 exerted cytotoxic effects in p53-mutated ESCC cells in a dose-dependent manner and activated the p38 MAPK signaling pathway. These results prompted us to combine the p38 MAPK inhibitor LY2228820 with HDM-201 and evaluate this novel treatment strategy in a p53-mutant pre-clinical model of ESCC. We observed that HDM-201 and LY2228820 acted synergistically to decrease cell viability (p&amp;lt;0.01) and colony formation (p&amp;lt;0.01), as well as induction of apoptosis (p&amp;lt;0.01) and G2/M phase cell cycle arrest (p&amp;lt;0.01). The xenograft animal model confirmed our in vitro findings wherein the combined treatment exerted more potent anti-tumor activity (p&amp;lt;0.05). We also observed that silencing of p53 promoted resistance towards the MDM2 antagonist and did not induce apoptosis, highlighting that a functional p53 is required for inducing apoptosis after combined treatment. Furthermore, we observed that the combined treatment promoted ROS induced oxidative stress (p&amp;lt;0.01) and promoted DNA double strand breaks (DSBs) as evidenced by increased phosphorylation of H2AX (p&amp;lt;0.01), highlighting its potential as an effective therapeutic strategy. Conclusion: We provide novel pre-clinical evidence that inhibition of p38 MAPK signaling can augment the anti-tumor activity of an MDM2 antagonist in p53-mutant human tumor models of ESCC. Citation Format: Souvick Roy, Rachana Garg, David Wang, Ajay Goel. Dual inhibition of MDM2 and p38 MAPK signaling is a potential therapeutic strategy in esophageal squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 723.

E2F1-activated NRSN2 promotes esophageal squamous cell carcinoma progression through AKT/mTOR pathway

BackgroundNeurensin‑2 (NRSN2) has been reported to act as an oncogene in several types of human cancer. However, the molecular mechanism of NRSN2 in esophageal squamous cell carcinoma (ESCC) remains to be elucidated. MethodsThe mRNA expression levels of NRSN2 in ESCC tissues and cell lines were evaluated by quantitative real-time PCR (qRT-PCR). The protein expression levels of NRSN2 in ESCC tissues were measured by Immunohistochemical (IHC) method. Luciferase reporter and chromatin immunoprecipitation assays were conducted to confirm the upstream transcription factor of NRSN2. Loss- and gain-function assays were conducted to evaluate the effects of NRSN2 on ESCC cells proliferation, migration, and invasion. The function of NRSN2 was validated in vivo using tumor xenografts. The relationship between NRSN2 and AKT/mTOR pathway were confirmed by western blot assay. ResultsThe expression level of NRSN2 was increased in ESCC tissues and cell lines. High expression level of NRSN2 was correlated with depth of invasion, lymph node metastasis, TNM stage, and poor prognosis of ESCC patients. NRSN2 was transcribed by E2F1. Knockdown of NRSN2 significantly inhibited ESCC cells proliferation, migration, and invasion, whereas NRSN2 overexpression showed reverse phenotypes. Overexpression of NRSN2 also enhanced ESCC tumorigenicity in vivo. Furthermore, the E2F1/NRSN2 axis promoted proliferation, migration, and invasion of ESCC cells by activating the AKT/mTOR pathway. ConclusionNRSN2 is a direct transcriptional target of E2F1 to promote tumor progression in ESCC. NRSN2 may be a diagnostic biomarker or treatment target for ESCC.

FOXM1 Promotes Malignant Proliferation of Esophageal Squamous Cell Carcinoma Through Transcriptional Activating CDC6.

Forkhead box M1 (FOXM1) is a proliferative transcription factor and plays a vital role in many cancers. However, the function and molecular mechanism of FOXM1 in esophageal squamous cell carcinoma (ESCC) remain poorly understood. Hence, we aim to clarify the molecular basis of FOXM1-mediated ESCC progression. In this study, bioinformatics analysis showed that FOXM1 was mainly involved in key signal pathways, including cell proliferation, cell cycle, and homologous recombination in ESCC, and predicted that CDC6 might be a potential regulatory target gene of FOXM1. The results revealed that FOXM1 and CDC6 were significantly overexpressed in ESCC tissue and cell line, and their expression was positively correlated. Further studies showed that FOXM1 directly transcriptionally activated CDC6 by binding to its promoter region in ESCC cells. Moreover, FOXM1 mediated ESCC cell proliferation by regulating CDC6 expression, which may be related to promoting G1-S phase transition of cell cycle. Taken together, FOXM1-CDC6 axis mediates ESCC malignant proliferation and may serve as a potential biological target for ESCC treatment.

CSMD1 suppresses cancer progression by inhibiting proliferation, epithelial-mesenchymal transition, chemotherapy-resistance and inducing immunosuppression in esophageal squamous cell carcinoma

Human CUB and Sushi multiple domains (CSMD1) is considered a crucial role in cancer progression, but the specific function in esophageal squamous cell carcinoma (ESCC) is not clear. Understanding the role of CSMD1 in ESCC progression may lead to a novel strategy for ESCC treatment. Here, we found that both CSMD1 mRNA and protein levels were downregulated in ESCC tissues. Reduced CSMD1 expression was correlated with a poor prognosis in ESCC patients. CSMD1 expression inhibited proliferation, migration and invasion in ESCC cell lines in vitro. CSMD1 deficiency in established xenografted tumors increases tumor size and weight. We further found that CSMD1-overexpression cells are more sensitive to chemotherapy. Moreover, we addressed the role of CSMD1 in the CD8+ T cell immune response. An in vitro killing assay showed that the cytotoxicity of CD8+ T cells was inhibited in CSMD1-overexpression tumor cells. In vivo, in CSMD1 deficiency tumor-bearing mice activation and expansion of CD8+ T cells were increased. Further investigation showed that CSMD1 expression on tumor cells was positively correlated with CD8+ T cells infiltration and cytokines secretion. These findings highlight that CSMD1 is a tumor suppressor gene in ESCC patients and a positive regulator of CD8+ T cells expansion and activation, and could increase cytokines secretion, indicating that tumor cell-associated CSMD1 might be a target for ESCC.

MiR-26b-5p in small extracellular vesicles derived from dying tumor cells after irradiation enhances the metastasis promoting microenvironment in esophageal squamous cell carcinoma

Radiation therapy is effective in achieving local control in esophageal squamous cell carcinoma; however, changes in the tumor microenvironment induced by radiation can also promote metastasis. Dying tumor cells play vital roles in promoting the survival of living tumor cells; however, few studies have investigated the effects of dying tumor cells on the tumor microenvironment. Since myeloid-derived suppressor cells (MDSCs) and macrophages constitute the pre-metastatic niche (PMN), we used a 4-nitroquinoline-1-oxide induced in situ tumor model to investigate the effects of irradiation on MDSCs and macrophages in esophageal squamous cell carcinoma (ESCC). When primary tumor sites were irradiated, we observed an increase in MDSCs in the spleen and the deposition of PMN components in lung and liver. Enhanced MDSC accumulation and function were induced by small extracellular vesicles (sEVs) isolated from irradiated tumor-bearing mice. The MDSC induction function of sEVs after irradiation was reaffirmed using sEVs derived from ESCC cell lines. The irradiation-induced upregulation of miR-26b-5p in sEVs enhanced MDSC expansion and activation by targeting phosphatase and tensin homolog. Our results first elucidated a mechanism by which dying tumor cells enhanced the deposition of PMN components and potentiated MDSCs in ESCC after irradiation. sEVs played a vital role in mediating signals between the primary tumor and the microenvironment to form a metastasis-promoting microenvironment after irradiation. Furthermore, miR-26b-5p or PI3K/AKT signaling pathway inhibitors should be evaluated in clinical trials in combination with radiotherapy as a strategy to improve outcomes.

Integrin-linked kinase affects the sensitivity of esophageal squamous cell carcinoma cells to chemotherapy with cisplatin via the Wnt/beta-catenin signaling pathway

ABSTRACT Recent studies have shown that the expression of integrin-linked kinase (ILK) was related to the occurrence, development, and malignant progression of esophageal squamous cell carcinoma (ESCC). However, research on the relationship between ILK and the chemosensitivity of ESCC has to date not been reported. The present study found that ILK was highly expressed in ESCC cell lines, and the overexpression of ILK in ESCC cells reduced the incidence of cell apoptosis and alleviated the cytotoxicity on cells induced by cisplatin (CDDP). Inversely, ILK knockdown increased CDDP-induced apoptosis and had an inhibitive effect on the malignant phenotype of ESCC, including cell proliferation, invasion, and migration. In addition, ILK knockdown in ESCC cells inhibited the expression of beta (β)-catenin and activated the wingless/integrated (Wnt) signaling pathway. Furthermore, cellular MYC (c-MYC) and Cylin D1 were the target genes of the Wnt signaling pathway. Rescue experiments showed that the overexpression of β-catenin reversed a tumor’s inhibition and apoptosis abilities induced by ILK knockdown. In conclusion, ILK potentially reduced the CDDP sensitivity of ESCC cells by influencing the activity of the Wnt/β-catenin signaling pathway.

Tumor-associated fibroblasts derived exosomes induce the proliferation and cisplatin resistance in esophageal squamous cell carcinoma cells through RIG-I/IFN-β signaling

ABSTRACT Esophageal squamous cell carcinoma (ESCC) is a common type of malignant cancer. There is growing evidence suggesting that exosomes may participate in the cellular communication of tumor-associated fibroblasts (TAFs). However, the cisplatin resistance of TAF-derived exosomes to ESCC cells remains to be further studied. Exosomes were isolated from TAFs and characterized with Western blot and TEM assays. ESCC cell lines (TE-1 and KYSE-150) were incubated with TAFs-derived exosomes. To explore the biological function of TAF-derived exosomes in ESCC cell proliferation, apoptosis, and chemosensitivity, we conducted MTT assays and Flow Cytometry. The effects in vivo were also verified via Xenograft mice models. We found that TAFs-derived exosomes led to enhanced cell proliferation and reduced apoptosis of cells, accompanied by increased expression of RIG-I/IFN-β, and TAFs derived exosomes may affect the chemosensitivity to cisplatin via RIG-I/IFN-β signaling in ESCC. Taken together, ESCC cells could communicate with TAFs cells via TAFs-derived exosomes. Our findings might represent a novel mechanism involved in ESCC and may provide a potential biomarker for ESCC.