Esophageal Epithelial Cell Line Research Articles

Modeling Epithelial Homeostasis and Perturbation in Three-Dimensional Human Esophageal Organoids.

Background: Esophageal organoids from a variety of pathologies including cancer are grown in Advanced Dulbecco's Modified Eagle Medium-Nutrient Mixture F12 (hereafter ADF). However, the currently available ADF-based formulations are suboptimal for normal human esophageal organoids, limiting the ability to compare normal esophageal organoids with those representing a given disease state. Methods: We have utilized immortalized normal human esophageal epithelial cell (keratinocyte) lines EPC1 and EPC2 and endoscopic normal esophageal biopsies to generate three-dimensional (3D) organoids. To optimize the ADF-based medium, we evaluated the requirement of exogenous epidermal growth factor (EGF) and inhibition of transforming growth factor-(TGF)-β receptor-mediated signaling, both key regulators of the proliferation of human esophageal keratinocytes. We have modeled human esophageal epithelial pathology by stimulating esophageal 3D organoids with interleukin (IL)-13, an inflammatory cytokine, or UAB30, a novel pharmacological activator of retinoic acid signaling. Results: The formation of normal human esophageal 3D organoids was limited by excessive EGF and intrinsic TGFβ-receptor-mediated signaling. Optimized HOME0 improved normal human esophageal organoid formation. In the HOME0-grown organoids, IL-13 and UAB30 induced epithelial changes reminiscent of basal cell hyperplasia, a common histopathologic feature in broad esophageal disease conditions including eosinophilic esophagitis. Conclusions: HOME0 allows modeling of the homeostatic differentiation gradient and perturbation of the human esophageal epithelium while permitting a comparison of organoids from mice and other organs grown in ADF-based media.

FUT6 Suppresses the Proliferation, Migration, Invasion, and Epithelial-Mesenchymal Transition of Esophageal Carcinoma Cells via the Epidermal Growth Factor Receptor/Extracellular Signal-Regulated Kinase Signaling Pathway.

Esophageal cancer (ESCA) is a high-incidence disease worldwide, of which the 5-year survival rate remains dismal since the cellular basis of ESCA remains largely unclear. Herein, we attempted to examine the manifestation of fucosyltransferase-6 (FUT6) in ESCA and the associated mechanisms. The GSE161533 dataset was used to analyze a crucial gene in ESCA. The expression of FUT6 was investigated in normal esophageal epithelial cells and ESCA cell lines. Following FUT6 knockdown or overexpression, cell proliferation, migration, invasion, and levels of epithelial–mesenchymal transition (EMT)-related and epidermal growth factor receptor (EGFR)/extracellular signal-regulated kinase (ERK) signaling pathway-related proteins were evaluated using CCK-8, Transwell, and Western blotting with antibodies against EGFR, p-EGFR, E-cadherin, Vimentin, N-cadherin, ERK1/2, and p-ERK1/2), respectively. EGF was administered to stimulate the EGFR/ERK signaling pathway, followed by the assessment of cellular activity. Database analysis revealed that FUT6 was downregulated in the ESCA cells. Our study indicated that FUT6 is suppressed in various ESCA cell lines. Moreover, cell proliferation, invasion, migration, and EMT-related protein levels were conspicuously enhanced or restrained by FUT6 disruption or overexpression. FUT6 overexpression suppressed the malignant activities of the cells when stimulated by EGF, including inhibition of cell growth, movement, invasion, and EMT advancement, as well the reduction the levels of EGFR/ERK pathway proteins. In conclusion, FUT6 can suppress the EGFR/ERK signaling pathway activated by EGF, leading to the potential attenuation of ESCA cell proliferation, invasion, migration, and EMT.

Abnormal activation of genomic LINE1 elements caused by DNA demethylation contributes to lncRNA CASC9 overexpression in esophageal squamous cell carcinoma

Long noncoding RNA (lncRNA) cancer susceptibility 9 (CASC9) has been found to be overexpressed and functions as an oncogene in many cancer types. We investigated the molecular mechanism underlying CASC9 overexpression in esophageal squamous cell carcinoma (ESCC). Transcripts containing exons 2 and 6 and exons 4 and 6 showed the highest CASC9 expression levels in ESCC, no transcripts were detected in the normal esophageal epithelial Het1A cell line. The Long Interspersed Nuclear Element-1 (LINE1 or L1) element in the genome was found to participate in the evolution of lncRNA CASC9, the antisense promoter (ASP) of L1 provides the cis-regulatory elements necessary for CASC9 activation, and the antisense chain of L1 participates in the formation of exons of CASC9. The activation of the antisense promoter was due to the aberrant hypomethylation of L1 elements. An active enhancer element was identified in the downstream region of CASC9 gene by ChIP-seq and ChIP-qPCR. The interaction between ASP and the enhancer elements was confirmed by chromosome conformation capture (3C). Thus, our results suggest that the L1 ASP activation due to aberrant hypomethylation and downstream enhancer interaction plays a key role in the overexpression of lncRNA CASC9 in ESCC.

NEK2 contributes to radioresistance in esophageal squamous cell carcinoma by inducing protective autophagy via regulating TRIM21

BackgroundRadiotherapy (RT) has been identified as a vital treatment for esophageal squamous cell carcinoma (ESCC), while the development of radioresistance remains a major obstacle in ESCC management. The aim of this study was to investigate the effect of NIMA-related kinase 2 (NEK2) on radioresistance in ESCC cells and to reveal potential molecular mechanisms.MethodsHuman esophageal epithelial cells (HEEC) and human ESCC cell lines were obtained from the Research Center of the Fourth Hospital of Hebei Medical University (Shijiazhuang, China). Cell Counting Kit-8 (CCK-8) and flow cytometry assays were applied to assess the proliferation ability, cell cycle, apoptosis rates, and ROS production of ESCC cells. The colony-forming assay was used to estimate the effect of NEK2 on radiosensitivity. Autophagy was investigated by western blotting analysis, GFP-mRFP-LC3 fluorescence assay, and transmission electron microscopy (TEM).ResultsIn the present study, our results showed that NEK2 was associated with radioresistance, cell cycle arrest, apoptosis, ROS production, and survival of ESCC. NEK2 knockdown could significantly inhibit growth while enhancing radiosensitivity and ROS production in ESCC cells. Interestingly, NEK2 knockdown inhibited ESCC cell autophagy and reduced autophagic flux, ultimately reversing NEK2-induced radioresistance. Mechanistically, NEK2 bound to and regulated the stability of tripartite motif-containing protein 21 (TRIM21). The accumulation of NEK2-induced light chain 3 beta 2 (LC3B II) can be reversed by the knockdown of TRIM21.ConclusionThese results demonstrated that NEK2 activated autophagy through TRIM21, which may provide a promising therapeutic strategy for elucidating NEK2-mediated radioresistance in ESCC.

High LINC00626 expression promotes esophagogastric junction adenocarcinoma metastasis: the mediating role of the JAK1/STAT3/KHSRP axis

To investigate the role of JAK1/STAT3/KHSRP axis in mediating the regulatory effect of LINC00626 on progression of esophagogastric junction adenocarcinoma. We collected surgical tumor and adjacent tissue specimens from 64 patients with esophagogastric junction adenocarcinoma and examined the expression levels of LINC00626 and KHSRP. qRT-PCR was used to detect the expressions of LINC00626 and KHSRP in 6 esophageal adenocarcinoma cell lines (OE-19, TE-7, Bic-1, Flo-1, SK-GT-4, and BE-3) and a normal esophageal epithelial cell line (HET-1A). OE-19 and TE-7 cell lines with stable LINC00626 knockdown and FLO-1 and SK-GT-4 cells stably overexpressing LINC00626 were constructed by lentiviral transfection, and the changes in proliferation, migration and invasion of the cells were evaluated using Cell Counting Kit-8 (CCK-8) assay and Transwell migration/invasion assay. The expressions of KHSRP and JAK/STAT pathway proteins in the transfected cells were detected with Western blotting. The effects of LINC006266 knockdown and overexpression on subcutaneous tumor formation and lung metastasis of OE-19 and FLO-1 cell xenografts were tested in nude mice. The expression levels of LINC00626 and KHSRP were significantly increased in esophagogastric junction adenocarcinoma tissues and in esophageal adenocarcinoma cells. LINC00626 knockdown obviously inhibited the proliferation, migration and invasion of esophageal adenocarcinoma cells in vitro and decreased their tumor formation and lung metastasis abilities in nude mice, while overexpression of LINC00626 produced the opposite effects. In esophageal adenocarcinoma cells, LINC0626 knockdown significantly decreased and LINC00626 overexpression strongly enhanced the phosphorylation of JAK1 and STAT3. High LINC00626 expression promotes esophageal-gastric junction adenocarcinoma metastasis by activating the JAK1/STAT3/KHSRP signal axis.

A Mouse Model for Eosinophilic Esophagitis (EoE).

Eosinophilic esophagitis (EoE) is an emerging chronic T helper type 2 (Th2)-associated, allergic, and immune-mediated disease, characterized histologically by eosinophil-predominant mucosal inflammation and clinically by esophageal dysfunction. Over the past years, the prevalence of EoE has dramatically increased globally. Until recently, most studies of EoE focused on using human biopsies, which are also used for diagnostic purposes, or esophageal epithelial cell lines, which led to major advances in the understanding of EoE. Despite this, a robust mouse model that mimics human disease is still crucial for both understanding disease pathogenesis and as a preclinical model for testing future therapeutics. Herein, we describe a highly reproducible and robust model of EoE that can be performed using wild-type mice by ear sensitization with oxazolone (OXA) followed by intraesophageal challenges. Experimental EoE elicited by OXA mimics the main histopathological features of human EoE, including intraepithelial eosinophilia, epithelial and lamina propria thickening, basal cell hyperplasia, and fibrosis. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol: Induction of EoE in mice using oxazolone Support Protocol 1: Preparing the mouse esophagus for histological analysis Support Protocol 2: Assessment of epithelial and lamina propria thickness using H&E staining Support Protocol 3: Assessment of eosinophilic infiltration using anti-MBP and basal cell proliferation using anti-Ki-67 staining Support Protocol 4: Flow cytometry of mouse esophageal samples Support Protocol 5: ELISA on protein lysates of esophageal samples.

FUT6 Suppresses the Proliferation, Migration, Invasion, and Epithelial-Mesenchymal Transition of Esophageal Carcinoma Cells via the Epidermal Growth Factor Receptor/Extracellular Signal-Regulated Kinase Signaling Pathway.

Esophageal cancer (ESCA) is a high-incidence disease worldwide, of which the 5-year survival rate remains dismal since the cellular basis of ESCA remains largely unclear. Herein, we attempted to examine the manifestation of fucosyltransferase-6 (FUT6) in ESCA and the associated mechanisms. The GSE161533 dataset was used to analyze a crucial gene in ESCA. The expression of FUT6 was investigated in normal esophageal epithelial cells and ESCA cell lines. Following FUT6 knockdown or overexpression, cell proliferation, migration, invasion, and levels of epithelial–mesenchymal transition (EMT)-related and epidermal growth factor receptor (EGFR)/extracellular signal-regulated kinase (ERK) signaling pathway-related proteins were evaluated using CCK-8, Transwell, and Western blotting with antibodies against EGFR, p-EGFR, E-cadherin, Vimentin, N-cadherin, ERK1/2, and p-ERK1/2), respectively. EGF was administered to stimulate the EGFR/ERK signaling pathway, followed by the assessment of cellular activity. Database analysis revealed that FUT6 was downregulated in the ESCA cells. Our study indicated that FUT6 is suppressed in various ESCA cell lines. Moreover, cell proliferation, invasion, migration, and EMT-related protein levels were conspicuously enhanced or restrained by FUT6 disruption or overexpression. FUT6 overexpression suppressed the malignant activities of the cells when stimulated by EGF, including inhibition of cell growth, movement, invasion, and EMT advancement, as well the reduction the levels of EGFR/ERK pathway proteins. In conclusion, FUT6 can suppress the EGFR/ERK signaling pathway activated by EGF, leading to the potential attenuation of ESCA cell proliferation, invasion, migration, and EMT.

Hypoxia-induced factor-1α promotes radioresistance of esophageal cancer cells by transcriptionally activating LINC01116 and suppressing miR-3612 under hypoxia.

Esophageal cancer (EC) is a challenging tumor to treat with radiotherapy, often exhibiting resistance to this treatment modality. To explore the factors influencing radioresistance, we focused on the role of hypoxia-induced factor-1α (HIF-1α), and its interaction with the long noncoding RNA long intergenic nonprotein coding RNA 1116 (LINC01116). We analyzed the LINC01116 expression in EC and EC cell lines/human normal esophageal epithelial cell line (Het-1A). LINC01116 was silenced/overexpressed in EC109/KYSE30 cells under hypoxia, followed by radioresistance assessment. We measured HIF-1α levels in hypoxic EC cells and further validated the binding of HIF-1α with LINC01116, analyzing their interaction in EC cells. We then performed experiments in EC109 cells by transfection them with sh-HIF-1α/oe-LINC01116 to verify the effects. Additonally, we analyzed the localization of LINC01116 and its binding with miR-3612, followed by a combined experiment performed to validate the results. Our findings indicated that LINC01116 was highly expressed in EC and further elevated in hypoxic EC cells. LINC01116 was expressed at a high level in EC, which was further elevated in EC cells under hypoxic conditions. Knockdown of LINC01116 triggered EC cell apoptosis, thus suppressing radioresistance. Further investigation revealed that HIF-1α transcriptionally activated LINC01116 expression under hypoxia, and silencing HIF-1α lowered EC cell radioresistance by downregulating LINC01116. Under hypoxic conditions, LINC01116 could function as a sponge for miR-3612 and inhibit its expression. This interaction between LINC01116 and miR-3612 played a crucial role in mediating radioresistance in EC cells. Briefly, under hypoxic conditions, HIF-1α facilitates radioresistance of EC cells by transcriptionally activating LINC01116 expression and downregulating miR-3612.

MUC13 promotes the development of esophageal cancer by upregulating the expression of o-glycan process-related molecules

BackgroundEsophageal cancer is one of the most common malignant tumors in the world, which is characterized by poor prognosis, aggressiveness, and poor survival. Mucin 13 (MUC13) is a member of the membrane-bound mucin and located on chromosome 3q21.2 and consists of α and β subunits. It has been found that MUC13 is overexpressed in a variety of tumor cells and acts a vital role in the invasiveness and malignant progression of several types of tumors. However, the role and regulatory mechanism of MUC13 in the progression of esophageal cancer remain unclear.MethodsThe expression level of MUC13 was detected in 15 esophageal cancer tissues and 15 pairs of adjacent nontumor tissues by immunohistochemistry (IHC). In addition, the expression of MUC13 mRNA level in human esophageal cancer cell lines (EC9706 and ECA109 and TE-1) was measured by qRT-PCR. In vitro, after silencing MUC13 with lentiviral interference technology, CCK8 assay, clone formation assay, and flow cytometry were applied to investigate the proliferation activity, clone formation ability and anti-apoptosis ability of EC9706 and ECA109 cells. The tumor xenograft growth assay was used to confirm the influence of MUC13 knockdown on the growth of esophageal tumors in vivo. The qRT-PCR assay and western blot experiments were taken to study the mechanism of MUC13 regulating the proproliferation and antiapoptotic of esophageal cancer.ResultsThe results showed that MUC13 was overexpressed in esophageal cancer tissues and cell lines (EC9706 and ECA109 and TE-1), especially in EC9706 and ECA109 cells, but low expressed in human esophageal epithelial cell line (HEEC). Next, silencing MUC13 inhibits proliferation, blocks cell cycle progression, and promotes cell apoptosis in vitro, and restrains the growth of esophageal cancer tissues in vivo. Finally, MUC13 affects the proproliferation and antiapoptotic by regulating the expression of GLANT14, MUC3A, MUC1, MUC12, and MUC4 that closely related to O-glycan process.ConclusionsThis study proved that MUC13 is an important molecule that regulates the O-glycan process and then affects the progress of esophageal cancer. MUC13 may be a novel therapeutic target for patients with esophageal cancer.

Bioinformatics analysis of necroptosis‑related lncRNAs and immune infiltration, and prediction of the prognosis of patients with esophageal carcinoma.

Esophageal carcinoma (ESCA) is one of the most common malignancies in the world, and has high morbidity and mortality rates. Necrosis and long noncoding RNAs (lncRNAs) are involved in the progression of ESCA; however, the specific mechanism has not been clarified. The aim of the present study was to investigate the role of necrosis-related lncRNAs (nrlncRNAs) in patients with ESCA by bioinformatics analysis, and to establish a nrlncRNA model to predict ESCA immune infiltration and prognosis. To form synthetic matrices, ESCA transcriptome data and related information were obtained from The Cancer Genome Atlas. A nrlncRNA model was established by coexpression, univariate Cox (Uni-Cox), and least absolute shrinkage and selection operator analyses. The predictive ability of this model was evaluated by Kaplan-Meier, receiver operating characteristic (ROC) curve, Uni-Cox, multivariate Cox regression, nomogram and calibration curve analyses. A model containing eight nrlncRNAs was generated. The areas under the ROC curves for 1-, 3- and 5-year overall survival were 0.746, 0.671 and 0.812, respectively. A high-risk score according to this model could be used as an indicator for systemic therapy use, since the half-maximum inhibitory concentration values varied significantly between the high-risk and low-risk groups. Based on the expression of eight prognosis-related nrlncRNAs, the patients with ESCA were regrouped using the 'ConsensusClusterPlus' package to explore potential molecular subgroups responding to immunotherapy. The patients with ESCA were divided into three clusters based on the eight nrlncRNAs that constituted the risk model: The most low-risk group patients were classified into cluster 1, and the high-risk group patients were mainly concentrated in clusters 2 and 3. Survival analysis showed that Cluster 1 had a better survival than the other groups (P=0.016). This classification system could contribute to precision treatment. Furthermore, two nrlncRNAs (LINC02811 and LINC00299) were assessed in the esophageal epithelial cell line HET-1A, and in the human esophageal cancer cell lines KYSE150 and TE1. There were significant differences in the expression levels of these lncRNAs between tumor and normal cells. In conclusion, the present study suggested that nrlncRNA models may predict the prognosis of patients with ESCA, and provide guidance for immunotherapy and chemotherapy decision making. Furthermore, the present study provided strategies to promote the development of individualized and precise treatment for patients with ESCA.

Direct and indirect effects of alcohol and its toxic metabolite acetaldehyde on human esophageal myofibroblasts and epithelial cells.

Mechanisms by which alcohol increases the risk of esophageal squamous cell carcinoma remain undefined. Human esophageal myofibroblasts (HEMFs) subjacent to the squamous epithelium are exposed directly to these agents via epithelial barrier defects and indirectly via factors derived from the exposed epithelium. Our aim was to investigate the cellular biology of HEMFs and HEMF-esophageal epithelial cell interactions in response to alcohol and its toxic metabolite acetaldehyde. An immortalized HEMF and a human esophageal epithelial cell line (Epi) were treated with alcohol (0 to 200 mM) or acetaldehyde (0 to 100 μM) in a cyclic fashion or incubated with supernatants collected from treated cells. Healthy cell %, reactive oxygen species (ROS), and proliferation were assessed via flow cytometry, luminescence, scratch wound, and colorimetric assays, respectively. A 15-plex multiplex assay was performed on cell supernatants, followed by IL-6 and IL-8 qRT-PCR and ELISA. Healthy HEMF decreased to less than 80% at 30 mM alcohol and 70 μM acetaldehyde, with microscopic changes at 40 μM acetaldehyde. HEMF ROS was detected at 100 mM alcohol and 80 μM acetaldehyde. Supernatants from 30 mM alcohol- or 40 μM acetaldehyde-treated HEMFs increased Epi proliferation more than two-fold that of lower doses. In the complementary studies, healthy Epi cells decreased to less than 80% at 50 mM and 70 μM acetaldehyde, with microscopic changes at 40 μM. Supernatants from Epi treated with 50 mM alcohol or 40 μM acetaldehyde increased HEMF proliferation more than two-fold that of lower doses. A multiplex assay of supernatants showed the greatest increase in concentrations of IL-6 and IL-8 in HEMFs and in Epi treated with higher doses of alcohol or acetaldehyde. Neutralization of IL-6 and IL-8 in supernatants of HEMFS and esophageal epithelial cells inhibited the proliferation of Epi and HEMFs, respectively. Alcohol and acetaldehyde doses in which the majority of HEMFs and epithelial cells are healthy, elicit the production of paracrine mediators with pro-proliferative effects on neighboring cells. Understanding the effect of alcohol and acetaldehyde on HEMFs and HEMF-epithelial interactions could help to identify the molecular basis by which alcohol increases the risk for esophageal cancer.

CCT6A promotes esophageal squamous cell carcinoma cell proliferation, invasion and epithelial-mesenchymal transition by activating TGF-β/Smad/c-Myc pathway.

Chaperonin-containing TCP1 subunit 6A (CCT6A) facilitates several malignant cancer behaviors, but its regulation of esophageal squamous cell carcinoma (ESCC) has not been reported. This study aimed to investigate the effect of CCT6A on cell proliferation, apoptosis, invasion and epithelial-mesenchymal transition (EMT) and its interaction with the TGF-β/Smad/c-Myc pathway in ESCC. CCT6A expression was detected in ESCC and normal esophageal epithelial cell lines by RT‒qPCR and western blotting. Furthermore, CCT6A siRNA, negative control (NC) siRNA, CCT6A encoding plasmid and NC encoding plasmid were transfected into OE21 and TE-1 cells. Subsequently, CCT6A siRNA- and NC siRNA-transfected cells were treated with TGF-β for rescue experiments. Cell proliferation, apoptosis, invasion, and E-cadherin/N-cadherin and p-Smad2/p-Smad3/c-Myc expression were detected. CCT6A expression was increased in KYSE-180, TE-1, TE-4 and OE21 cells compared with HET-1A cells. In both OE21 and TE-1 cells, CCT6A knockdown inhibited cell proliferation, invasion and N-cadherin expression while promoting cell apoptosis and E-cadherin expression; meanwhile, CCT6A overexpression had the opposite effects. Furthermore, in both OE21 and TE-1 cells, CCT6A knockdown decreased p-Smad2/Smad2, p-Smad3/Smad3 and c-Myc/GAPDH expression; CCT6A overexpression had the opposite effects. Next, TGF-β facilitated cell proliferation, invasion, and N-cadherin, p-Smad2/Smad2, p-Smad3/Smad2 and c-Myc/GAPDH expression while repressing cell apoptosis and E-cadherin expression in OE21 and TE-1 cells; importantly, TGF-β could compensate for the regulation of CCT6A knockdown on these activities. CCT6A facilitates ESCC malignant activities by activating the TGF-β/Smad/c-Myc pathway, which sheds light on the identification of a possible therapeutic target in the management of ESCC.

Abstract 1556: CDKN3 inhibition enhances the antitumor effect of paclitaxel by promoting abnormal mitosis of cancer cells

Abstract Background: Paclitaxel (PTX) is one of the key drugs in clinical practice for esophageal squamous cell carcinoma (ESCC), however, therapeutic effects of PTX alone are not sufficient. PTX causes activation of spindle assembly checkpoint resulting in mitotic arrest of cancer cells. Recently, the antitumor effect of PTX has been shown to depend on aberrant chromosome segregation and abnormal spindle formation. Whereas, recent reports showed that cyclin dependent kinase inhibitor 3 (CDKN3) was often overexpressed in various human cancer tissues which was attributed to the higher mitotic activity in cancer cells, and loss of CDKN3 induced abnormal mitosis and centrosome overduplication. Therefore, we hypothesized that the combination of PTX and CDKN3 inhibition may promote mitotic errors in cancer cells. The aim of this study is to examine the combined effect of PTX and CDKN3 inhibition on ESCC. Methods: The expression levels of CDKN3 were compared between ESCC cell lines (TE1, TE5, TE6, TE8, TE10, and TE11) and normal esophageal epithelial cell line (EPC2-hTERT). CDKN3 knockdown ESCC cells using shRNA were created. Cell viability assay (WST-1 and clonogenic assay), immunofluorescence microscopy for measuring the number of centrosomes or spindle microtubules, and time-lapse images for assessing mitosis and cell fate were performed. Results: The expression levels of CDKN3 in ESCC cells were high compared to normal esophageal epithelial cells. Here, TE6 and TE10 ESCC cells were selected for further experiments based on higher CDKN3 expression. WST-1 assays showed an increased sensitivity to PTX after CDKN3 knockdown. Clonogenic assay showed reduced clonogenicity with CDKN3 knockdown, which was further reduced when exposed to 1 nM PTX (no interaction by two-way ANOVA analysis). Quantification of centrosomes revealed an increased frequency of centrosome overduplication in cells with CDKN3 knockdown, and it was further increased when treated with 1 nM PTX. Quantification of microtubules revealed CDKN3 knockdown cells with 1nM PTX had irregular multipolar spindle formation in almost half of the cells in mitosis. In time-lapse images, mitotic errors were more frequent ( > 80% in combination vs 54% in PTX vs 32% in CDKN3 knockdown) and most of the daughter cells after abnormal mitoses resulted in cell death in interphase or did not undergo another cell division. The cumulative cell death was significantly increased in combination treatment with PTX and CDKN3 inhibition compared to PTX treatment alone (Hazard ratio 2.22; 95% CI 1.43 - 3.45, p = 0.0004 ) and CDKN3 inhibition alone (Hazard ratio 3.09; 95% CI 1.92 - 4.98, p < 0.0001). Conclusions: CDKN3 knockdown increased the frequencies of centrosome overduplication and multipolar spindle formation when combined with PTX exposure. These mitotic errors caused multipolar divisions and subsequent cell death. Targeting CDKN3 could be a novel anti-cancer strategy. Citation Format: Shigeki Kataoka, Junichi Matsubara, Trang H. Vu, Tomohiro Kondo, Tomoki Saito, Yosuke Mitani, Osamu Kikuchi, Atsushi Yamada, Shinya Ohashi, Manabu Muto. CDKN3 inhibition enhances the antitumor effect of paclitaxel by promoting abnormal mitosis of cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1556.

Cellular proteomic profiling of esophageal epithelial cells cultured under physioxia or normoxia reveals high correlation of radiation response

ObjectiveTo investigate the radiation response and proteomic profiling of esophageal epithelial cells cultured under physioxia and normoxia. MethodsThe human immortalized normal esophageal epithelial cell line SHEE cells were cultured under normoxia (21%) and physioxia (4%), respectively. A clonogenic assay was performed to evaluate the radiation response of SHEE cells. Cellular proteomic profiling of SHEE cells maintained under physioxia and normoxia was conducted to determine the differentially expressed proteins. Then, the identified differentially expressed proteins were validated by Western blot. ResultsSHEE cells exposed to normoxia showed an increased radiation response compared to physioxia (irradiation dose ≥10 ​Gy, P< 0.05). Over 1200 non-redundant proteins were identified in the collected samples. Protein expression was compared between physioxia and normoxia, 42 proteins were downregulated and 45 proteins upregulated, in which oxidative phosphorylation was the most significantly enriched pathway. When cells were cultured under normoxia conditions, the induction of antioxidant genes appeared to contribute to form a phenotype adapted to the environment with high oxygen-content. Further analysis validated NRF2, BIP, VCP, SOD1, and YAP1 were the key regulators of this phenotype. ConclusionsCompared with physioxia, normoxic cell culture condition can enhance the radiation response. This study could stimulate in vivo microenvironment, and provide a basis for radiation-induced normal tissue damage.

The role of TMEM26 in disrupting tight junctions and activating NF-κB signaling to promote epithelial-mesenchymal transition in esophageal squamous cell carcinoma

ObjectivesMetastasis is one of the biggest challenges in the management of Esophageal Squamous Cell Carcinoma (ESCC), of which molecular mechanisms remain elusive. The present study aimed to explore the roles and underlying mechanisms of Transmembrane protein 26 (TMEM26) in ESCC. MethodTMEM26 expressions in tumorous and adjacent tissues from patients with ESCC and in normal esophageal epithelial and ESCC cell lines were detected by immunostaining and western blotting, respectively. The Epithelial-Mesenchymal Transition (EMT), a critical process during metastasis, was investigated by wound healing and Transwell assays, and EMT-related proteins were examined after the TMEM26 alteration in ESCC cell lines. NF-κB signaling activation and Tight Junction (TJ) protein expression were analyzed by western blotting and immunofluorescence, respectively. In vivo verification was performed on the liver metastatic murine model. ResultsCompared with non-cancerous esophageal tissues and cells, the TMEM26 expression level was higher in ESCC samples and cell lines, where the plasma membrane localization of TMEM26 was observed. The EMT-related processes of ESCC cells were suppressed by RNAi depletion of TMEM26 but aggravated by TMEM26 overexpression. Mechanistically, TMEM26 promoted NF-κB signaling to accelerate EMT in ESCC cells. The plasma membrane presentation and assembly of TJ proteins were impaired by TMEM26. ConclusionOverall, TMEM26 acts as a critical determinant for EMT in ESCC cells by disrupting TJ formation and promoting NF-κB signaling, which may be a potential therapeutic target for treating metastatic ESCC.

MiR-214-3p targets Ras-related protein 14 (RAB14) to inhibit cellular migration and invasion in esophageal Cancer cells

BackgroundMicroRNA (miR)-214-3p is emerging as an important tumor suppressor in esophageal cancer. In this study, we examined the interaction between miR-214-3p and RAB14, a membrane trafficking protein shown to exert oncogenic functions in other malignancies, in esophageal cancer cells.MethodsStudies were performed in a human esophageal epithelial cell line and a panel of esophageal cancer cell lines, as well in human specimens. MiR-214-3p expression was measured by digital PCR. Biotinylated RNA pull-down and luciferase reporter assays assessed binding. The xCELLigence RTCA system measured cell migration and invasion in real time. A lentiviral expression vector was used to create an esophageal cancer cell line stably expressing miR-214-3p.ResultsMiR-214-3p expression was decreased in esophageal cancer cell lines and human specimens compared to non-malignant controls. RAB14 mRNA stability and protein expression were decreased following miR-214-3p overexpression. Binding between miR-214-3p and RAB14 mRNA was observed. Either forced expression of miR-214-3p or RAB14 silencing led to a marked decrease in cellular migration and invasion. Esophageal cancer cells stably expressing miR-214-3p demonstrated decreased growth in a subcutaneous murine model.ConclusionsThese results further support the tumor-suppressive role of miR-214-3p in esophageal cancer cells by demonstrating its ability to regulate RAB14 expression.

Novel thiazolidines of potential anti-proliferation properties against esophageal squamous cell carcinoma via ERK pathway

The discovery of a new class of extracellular-signal-regulated kinase (ERK) inhibitors has been achieved via developing novel 2-imino-5-arylidene-thiazolidine analogues. A novel synthetic method employing a solid support-mediated reaction was used to construct the targeted thiazolidines through a cascade reaction with good yields. The chemical and physical stability of the new thiazolidine library has successfully been achieved by blocking the labile C5-position to aerobic oxidation. A cell viability study was performed using esophageal squamous cell carcinoma cell lines (KYSE-30 and KYSE-150) and non-tumorous esophageal epithelial cell lines (HET-1A and NES-G4T) through utilization of an MTT assay, revealing that (Z)-5-((Z)-4-bromobenzylidene)-N-(4-methoxy-2-nitrophenyl)-4,4-dimethylthiazolidin-2-imine (6g) was the best compound among the synthesized library in terms of selectivity. DAPI staining experiments were performed to visualize the morphological changes and to investigate the apoptotic activity. Moreover, western blots were used to probe the mechanism/pathway behind the observed activity/selectivity of thiazolidine 6g which established selective inhibition of phosphorylation in the ERK pathway. Molecular modeling techniques have been utilized to confirm the observed activity. A molecular docking study revealed similar binding interactions between the synthesized thiazolidines and reported co-crystalized inhibitors with ERK proteins. Thus, the present study provides a starting point for the development of interesting bioactive 2-imino-5-arylidene-thiazolidines.

Esophageal Squamous Cancer from 4NQO-Induced Mice Model: CNV Alterations.

Squamous esophageal carcinoma is a common pathological type of esophageal carcinoma around the world. The prognosis of esophageal carcinoma is usually poor and diagnosed at late stages. Recently, research suggested that genomic instability occurred in esophageal cells during the development of esophageal squamous cell carcinoma (ESCC). Identifying prognostic and specific genomic characteristics, especially at the early hyperplasia stage, is critical. Mice were given 4-nitroquinoline 1-oxide (4NQO) with drinking water to induce esophageal cancer. The immortalized human esophageal epithelial cell line (NE2) was also treated with 4NQO. We performed histologic analyses, immunofluorescence, and immunohistochemical staining to detect DNA damage at different time points. Whole-exome sequencing was accomplished on the esophagus tissues at different pathological stages to detect single-nucleotide variants and copy number variation (CNV) in the genome. Our findings indicate that all mice were tumor-forming, and a series of changes from simple hyperplasia (ESSH) to intraepithelial neoplasia (IEN) to esophageal squamous cell carcinoma (ESCC) was seen at different times. The expression of γ-H2AX increased from ESSH to ESCC. In addition, mutations of the Muc4 gene were detected throughout the pathological stages. Furthermore, CNV burden appeared in the esophageal tissues from the beginning of ESSH and accumulated more in cancer with the deepening of the lesions. This study demonstrates that mutations caused by the early appearance of DNA damage may appear in the early stage of malignant tissue before the emergence of atypia. The detection of CNV and mutations of the Muc4 gene may be used as an ultra-early screening indicator for esophageal cancer.

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.

Identification and function of circular RNA hsa_circ_0071106: A novel biomarker for differentiation degree of esophageal squamous cell carcinoma

BackgroundEsophageal squamous cell carcinoma (ESCC) has a high degree of malignancy, and there is currently no effective treatment. Circular RNA is a novel endogenous noncoding RNA with a stable loop structure. Several theories have been proposed regarding its biogenesis and usefulness as a biomarker in various cancers. Here we explore the predictive value and potential functions of a candidate circRNA (hsa_circ_0071106) in ESCC. MethodsThe altered expression of hsa_circ_0071106 was validated in clinical tissue samples from 64 patients with ESCC. The correlation between the clinical characteristics of these patients and the expression of hsa_circ_0071106 was analyzed by the chi-square test. The receiver operating characteristic (ROC) curves and the area under the ROC curve (AUC) were used to evaluate the diagnostic value of hsa_circ_0071106. The human esophageal carcinoma cell lines ECA109 and ECA9706 and the normal human esophageal epithelial cell line (HET-1A) were applied for functional analysis of hsa_circ_0071106. qRT-PCR, sanger sequencing, agarose gel electrophoresis, RNase R digestion assay, Actinomycin D inhibition assay, nucleoplasm separation assay, and FISH assays were utilized to verify the circular characteristics and subcellular localization of hsa_circ_0071106. SiRNA and circRNA interference lentivirus was constructed to inhibit the expression of hsa_circ_0071106 in the ECA109 and ECA9706 cell lines. We used the EdU assay, Transwell assay, and flow cytometry to detect changes in cell proliferation, invasion, migration, and apoptosis. ResultsWe identified that hsa_circ_0071106 showed significantly decreased expression levels in ESCC cells (P < 0.001) and tissue samples (P < 0.001). The correlation analysis of clinicopathological features and gene expression revealed that low expression of hsa_circ_0071106 was related to poor differentiation grade (P < 0.05). ROC curves indicated that hsa_circ_0071106 might have a diagnostic value for ESCC (AUC = 0.826, 95% CI: 0.748–0.904) and a predictive value for a high degree of histological differentiation (AUC = 0.730, 95% CI: 0.607–0.854). Hsa_circ_0071106 has a stable circular structure and was primarily localized in the cytoplasm. A transient knockdown of hsa_circ_0071106 by siRNA promotes proliferation, migration, and invasion and inhibits apoptosis of ESCC cells. A steady knockdown of hsa_circ_0071106 by a lentivirus knockout vector significantly promoted cell migration and invasion in ECA109 and ECA9706 cell lines. ConclusionHsa_circ_0071106 was a downregulated circRNA related to ESCC and promoted ESCC progression by regulating cell migration and invasion. These findings suggest that hsa_circ_0071106 could be a promising diagnostic biomarker and potential therapeutic target and might predict ESCC’s histological differentiation degree.