Apoptosis In Esophageal Squamous Cell Carcinoma Research Articles

Clinical significance of peroxiredoxin 2 in esophageal squamous cell carcinoma and its role in cell proliferation and apoptosis <i>in vitro,/i>

Purpose: To evaluate the expression of peroxiredoxin 2 (PRDX2) and its clinical significance in esophageal squamous cell carcinoma (ESCC) and its effect on the proliferation and apoptosis of ESCC cells.Methods: The expression of PRDX2 in clinical tissues (120 samples of tumor tissues compared to 20 samples of non-tumor tissues) was determined. The tissues were divided into high-expression group (n = 56) or low-expression group (n = 64) based on the level of PRDX2. Association between PRDX2 expression and clinicopathological features of patients was further analyzed. In vitro, si-NC and si- PRDX2 were transfected into ECA-109 cells, respectively, to determine the influences of PRDX2 on the function of ESCC cells. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the different expressions of PRDX2 in the clinical tissues.Results: The results from qRT-PCR indicated that PRDX2 was upregulated in ESCC tissues compared to normal control. Correlation between the expression of PRDX2 and clinical pathological data revealed that the expression of PRDX2 showed correlation with tumor differentiation, size, and clinical tumor node metastasis (TNM) stage. Modulation of PRDX2 expression by transfecting si-PRDX2 in ESCC cell lines demonstrated effective regulation of cell proliferation and apoptosis. Specifically, it was observed that cell proliferation decreased, while cell apoptosis was increased.Conclusion: Peroxiredoxin 2 is a novel factor that plays a significant role in ESCC progression, and constitutes a potential biomarker and therapeutic target for ESCC.

Linc01614 Regulates the Proliferation, Apoptosis, and Chemotherapy Resistance in Esophageal Squamous Cell Carcinoma by Targeting Mir-4775.

Esophageal squamous cell carcinoma (ESCC), a widely known esophageal disease, severely affects people's health. Numerous investigations demonstrated that long non-coding RNAs (lncRNAs) performed key jobs inside a wide scope of organic cycles and stand out in malignant growth. Our study planned to investigate the roles and mechanisms of linc01614 in ESCC. A Total of 60 ESCC tissue samples including 30 patients with cisplatin sensitivity and 30 patients with cisplatin resistance, who received DDP-based treatment, were obtained from Zhuhai People's Hospital, Zhuhai City during 2021. These tissues were frozen and saved in a -80 °C ultra-low temperature freezer. We performed CCK-8, clone formation, flow cytometry assays to determine the effect of linc01614 on ESCC progression, and explored the specific mechanism of linc01614 in ESCC cell proliferation, apoptosis, and chemotherapy resistance. linc01614 expression was upregulated in ESCC tissues and cells compared with non-tumor tissues and human normal esophageal epithelial cells (Het-1A). Knockdown of linc01614 repressed cell expansion, chemotherapy opposition, and advanced cell apoptosis in ESCC. Besides, linc01614 regulated the expression of miR-4775 as a competitive endogenous RNA (ceRNA). The linc01614/miR-4775 axis played an important role in ESCC progression and drug resistance, revealing that linc01614 is a promising target in ESCC treatment.

A demonstration based on multi-omics transcriptome sequencing data revealed disulfidptosis heterogeneity within the tumor microenvironment of esophageal squamous cell carcinoma

BackgroundIt is of great concern to identify prognostic signatures for the prediction and prediction of esophageal squamous cell carcinoma (ESCC), which is the lethal pathological type of malignancy.MethodBulk RNA sequencing and scRNA-seq data were retrieved from GSE53624, GSE53622, and GSE188900. Disulfidptosis-related differentially expressed genes (DEGs) were identified between disulfidptosis-high score and disulfidptosis-low score groups. Functional annotation of DEGs were analyzed by Gene Ontology (GO). Consistent clustering and co-expression modules were analyzed, and then constructed a risk score model via multivariate Cox regression analysis. Immune infiltration and immunotherapy response analyses were conducted based on risk score. qRT-PCR, colony formation assay, and flow cytometry analysis were conducted in KYSE-150 and TE-1 cell lines.ResultsSeven genes (CD96, CXCL13, IL2RG, LY96, TPK1, ACAP1, and SOX17) were selected as marker genes. CD96 and SOX17 are independent prognostic signatures for ESCC patients, with a significant correlation with infiltrated immune cells. ESCC patients had worse response to nivolumab in the high-risk group. Through cellular experiments, we found that CD96 expression was associated with apoptosis and cell cycle ESCC cells.ConclusionIn a word, the risk score based on disulfidptosis is associated with prognosis and the immune microenvironment, which may direct immunotherapy of ESCC. The key gene of risk score, namely CD96, plays a role in proliferation and apoptosis in ESCC. We offer an insight into the exploration of the genomic etiology of ESCC for its clinical management.

Highly Expressing SCARA5 Promotes Proliferation and Migration of Esophageal Squamous Cell Carcinoma.

Background Thrombospondin type 1 domain-containing 7A (THSD7A) was reported to play a procancer role in esophageal squamous cell carcinoma (ESCC). The aim of the study was to screen the downstream functional genes of THSD7A and explore their functions in ESCC, based on the reported research into THSD7A function and on gene microarrays. Methods We adopted quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and Celigo high-content screening (HCS) technology to screen the downstream genes of THSD7A. The expression level of target genes was examined by PCR, western blot, and immunohistochemistry (IHC). The effects of these target genes on ESCC malignant biological behavior were performed in vivo and in vitro. The Kaplan-Meier (K-M) survival analysis and Cox regression were used to analyze the prognostic significance of target genes in ESCC patients. Experiments in the literature on liver cancer (LC) were repeated to verify the functions of these genes in different tumors. We further explored the cancer-promoting mechanism of target genes in ESCC by sequencing of the genes' exons. Results Scavenger receptor class A member 5 (SCARA5) was proved to be the downstream driving gene of THSD7A. SCARA5 promoted cell proliferation and migration but inhibited apoptosis in ESCC. IHC results confirmed that SCARA5 expression in ESCC exceeded that in normal tissues. The K-M survival analysis indicated that SCARA5 expression quantity was not related to prognosis, but tumor volume and T classification were both the independent prognostic factors. Repetition of experiments in LC in the literature confirmed that SCARA5 had exactly opposite functions in EC and LC. Conclusion SCARA5 was related to the development and occurrence of ESCC. Our findings suggested that it was a potentially diagnostic individualized therapeutic target for ESCC in the future and that its application could possibly be combined with that of upstream THSD7A gene.

GPx8 regulates apoptosis and autophagy in esophageal squamous cell carcinoma through the IRE1/JNK pathway

Glutathione peroxidase 8 (GPx8) belongs to a family of enzymes that have a critical role in controlling levels of reactive oxygen species (ROS). GPX family members have been associated with several cancers. Here, we examined the role of GPx8 in esophageal squamous cell carcinoma (ESCC). Immunohistochemical staining and western blot analysis were used to study the clinical significance of GPx8 in ESCC tissue. GPx8 was further evaluated in cells by MTT assay and colony formation. RT-PCR, western blot, immunofluorescence staining, TUNEL assay, TEM, and flow cytometry were used to assess the molecular mechanism underlying endoplasmic reticulum (ER) stress associated with GPx8 in ESCC cells. Xenografted tumor growth was used to assess the in vivo role of GPx8. We found that GPx8 was overexpressed in both ESCC cell lines and tumor tissue. GPx8 knockdown significantly suppressed ESCC proliferation and induced autophagy and apoptosis in ESCC cell lines, whereas GPx8 overexpression led to increased proliferation and inhibition of apoptosis. GPx8-mediated inhibition of apoptosis was associated with the ER stress pathway through inositol-requiring enzyme 1 (IRE1) and Jun N-terminal kinase (JNK). Knockdown of GPx8 in xenograft models of ESCC resulted in a significant reduction in tumor weight and volume, which was further reduced with IRE1 or JNK inhibitors. Our study suggests that GPx8 regulates apoptosis and autophagy in ESCC through the IRE1/JNK pathway in response to ER stress. Targeting this pathway might be a potential therapeutic strategy for ESCC.

Deregulated expression and subcellular localization of CPSF6, a circRNA-binding protein, promote malignant development of esophageal squamous cell carcinoma.

ObjectiveCleavage and polyadenylation specific factor 6 (CPSF6) has been documented as an oncoprotein in different types of cancer. However, functions of CPSF6 have not been investigated yet in esophageal squamous cell carcinoma (ESCC). Here, we aimed to investigate the potential clinical values and biological functions of CPSF6 in ESCC.MethodsFor determining the expression level of CPSF6 in ESCC patients, we analyzed published data, performed quantitative real-time polymerase chain reaction (RT-qPCR) and immunohistochemistry assays. Kaplan-Meier curves and log-rank tests were used for survival analyses. GO and KEGG analyses were done for CPSF6-related genes. Cell proliferation, colony formation and xenograft assays were conducted to verify the effects of CPSF6 on ESCC. In addition, cell cycle and apoptosis assays were also performed to manifest the functions of CPSF6 and circCPSF6. RNA pulldown and radioimmunoprecipitation (RIP) assays were used for confirming the interaction between circCPSF6 (hsa_circ_0000417) and CPSF6 protein. The regulatory relationship between CPSF6 protein and circCPSF6 was determined by RT-qPCR.ResultsWe found that CPSF6 was upregulated in ESCC tissues and overexpression of cytoplasmic CPSF6 was associated with poor prognosis. GO and KEGG analyses suggested that CPSF6 could mainly affect cell division in ESCC. Further experiments manifested that CPSF6 promoted cell proliferation and colony formationin vitro. Xenograft assay showed that knockdown of CPSF6 significantly decreased tumor growth rate in vivo. Subsequently, we verified that depletion of CPSF6 led to cell cycle arrest and apoptosis. Finally, we validated that CPSF6, as a circRNA-binding protein, interacted with and regulated its circular isoform circCPSF6 (hsa_circ_0000417), of which depletion also resulted in cell cycle arrest and cell apoptosis in ESCC. ConclusionsThese findings gave us insight that overexpression of cytoplasmic CPSF6 protein is associated with poor prognosis in ESCC and CPSF6 may function as an oncoprotein, at least in part, through regulating circCPSF6 expression.

MiR-204-5p inhibits cell proliferation and induces cell apoptosis in esophageal squamous cell carcinoma by regulating Nestin.

Esophageal cancer (EC) is a highly malignant gastrointestinal tumor, and esophageal squamous cell carcinoma (ESCC) is one of the most common histological types of EC. MicroRNAs (miRNAs) are small noncoding RNAs closely related to tumorigenesis and tumor progression. In addition, Nestin is an intermediate filament protein (class VI) and contributes to the progression of numerous tumors. However, the correlation between miRNAs and Nestin in ESCC remains unclear. This study aimed to investigate the relationship between miR-204-5p and Nestin in ESCC. First, Nestin-related miRNAs in ESCC were explored using RNA sequencing. In ESCC tissues and cell lines, the expression of miR-204-5p was decreased detected by quantitative real-time polymerase chain reaction (qPCR), whereas Nestin protein level was upregulated identified by Western blotting (WB). Besides, Nestin was the direct target of miR-204-5p in ESCC determined via the luciferase reported assay. Moreover, miR-204-5p regulated Nestin to inhibit ESCC cell proliferation detected by the colony formation assay and promote ESCC cell apoptosis identified using the flow cytometry and TUNEL assay. Furthermore, miR-204-5p suppressed tumorigenesis in vivo evaluated by the murine xenograft tumor model. In conclusion, these results indicated that miR-204-5p inhibited cell proliferation and induced cell apoptosis in ESCC through targeting Nestin, which might provide novel therapeutic targets for ESCC therapy.

Apatinib induces endoplasmic reticulum stress-mediated apoptosis and autophagy and potentiates cell sensitivity to paclitaxel via the IRE-1\u03b1\u2013AKT\u2013mTOR pathway in esophageal squamous cell carcinoma

BackgroundApatinib, a novel vascular endothelial growth factor receptor-2 (VEGFR-2) tyrosine kinase inhibitor, has been approved for the treatment of metastatic gastric cancer and other tumors. Apatinib exerts antiproliferative and proapoptotic effects in different kinds of cancer cells. However, the molecular mechanisms by which apatinib effective against esophageal squamous cell carcinoma (ESCC) have only been partially researched and whether it has a sensitizing effect on paclitaxel remains unclear.Materials and methodsThe effects of apatinib or paclitaxel on endoplasmic reticulum (ER) stress, autophagy, apoptosis and proliferation of ESCC cell lines were evaluated. Western blot and immunohistochemistry analyses were performed to detect the expression of related genes. The weight and volume of xenograft tumors in mice were measured.ResultsIn the current study, we elucidated the antiproliferative and ER-stress-mediated autophagy-inducing effects of apatinib on ECA-109 and KYSE-150 esophageal squamous cancer cells and identified the underlying mechanisms of its action. We demonstrated that apatinib not only inhibited the proliferation and induced the apoptosis of ESCC cells, but also activated ER stress and triggered protective autophagy. Moreover, inhibiting autophagy by chloroquine (CQ) enhanced the apatinib-induced apoptosis of ESCC cells through the IRE-1α–AKT–mTOR pathway. In addition, we showed, for the first time, the paclitaxel combined with apatinib and CQ exhibited the best antitumor effect on ESCC both in vivo and in vitro via the IRE-1α–AKT–mTOR pathway.ConclusionsOur data showed that apatinib induced ER stress, autophagy and apoptosis in ESCC. Inhibiting autophagy by CQ enhanced apatinib-induced apoptosis. The combination of apatinib and CQ sensitized ESCC cells to paclitaxel to induce apoptosis through the IRE-1α–AKT–mTOR signaling pathway, thus providing the basis for its use in innovative anticancer therapeutic strategies.Graphic abstract

Overexpressed NEDD8 as a potential therapeutic target in esophageal squamous cell carcinoma.

Objective:The hyperactivated neddylation pathway plays an important role in tumorigenesis and is emerging as a promising anticancer target. We aimed to study whether NEDD8 (neural precursor cell expressed, developmentally down-regulated 8) might serve as a therapeutic target in esophageal squamous cell carcinoma (ESCC).Methods:The clinical relevance of NEDD8 expression was evaluated by using The Cancer Genome Atlas (TCGA) database and tissue arrays. NEDD8-knockdown ESCC cells generated with the CRISPR/Cas9 system were used to explore the anticancer effects and mechanisms. Quantitative proteomic analysis was used to examine the variations in NEDD8 knockdown-induced biological pathways. The cell cycle and apoptosis were assessed with fluorescence activated cell sorting. A subcutaneous-transplantation mouse tumor model was established to investigate the anticancer potential of NEDD8 silencing in vivo.Results:NEDD8 was upregulated at both the mRNA and protein expression levels in ESCC, and NEDD8 overexpression was associated with poorer overall patient survival (mRNA level: P = 0.028, protein level: P = 0.026, log-rank test). Downregulation of NEDD8 significantly suppressed tumor growth both in vitro and in vivo. Quantitative proteomic analysis revealed that downregulation of NEDD8 induced cell cycle arrest, DNA damage, and apoptosis in ESCC cells. Mechanistic studies demonstrated that NEDD8 knockdown led to the accumulation of cullin-RING E3 ubiquitin ligases (CRLs) substrates through inactivation of CRLs, thus suppressing the malignant phenotype by inducing cell cycle arrest and apoptosis in ESCC. Rescue experiments demonstrated that the induction of apoptosis after NEDD8 silencing was attenuated by DR5 knockdown.Conclusions:Our study elucidated the anti-ESCC effects and underlying mechanisms of NEDD8 knockdown, and validated NEDD8 as a potential target for ESCC therapy.

Upregulation of SIX4 indicates poor clinical outcome and promotes tumor growth and cell metastasis in esophageal squamous cell carcinoma.

BackgroundThe role of sine oculis homeobox 4 (SIX4) has been found in some malignant tumors. However, there have been few studies on the function of SIX4 in esophageal squamous cell carcinoma (ESCC). This study aimed to explore the regulatory mechanism of SIX4 in ESCC.MethodsRT‐qPCR and Western blot analysis were used to measure mRNA and protein expression. The function of SIX4 was investigated using CCK‐8, colony formation, flow cytometry, wound healing and transwell assays. A mouse xenograft tumor assay was designed to perform in vivo experiments.ResultsSIX4 was upregulated in ESCC and indicated poor clinical outcomes in ESCC patients. Functionally, knockdown of SIX4 inhibited cell proliferation and induced apoptosis in ESCC. In addition, the silencing of SIX4 inhibited cell migration, invasion and EMT in ESCC. More importantly, upregulation of SIX4 could activate the PI3K/AKT pathway in ESCC cells and promote tumor growth in vivo.ConclusionsUpregulation of SIX4 indicates poor clinical outcomes in ESCC patients and promotes tumor growth and cell metastasis in ESCC.

MiR-624-3p Promotes Esophageal Squamous Cell Carcinoma Progression via Targeting Phosphatase and Tensin Homologue.

The emerging role of miRNA as regulators in esophageal squamous cell carcinoma (ESCC) progression has aroused great attention recently. In this study, the effects of miR-624-3p in ESCC progression were explored through cell proliferation, colony formation, cell cycle, and apoptosis analyses. Results showed that increased expression of miR-624-3p enhanced cancer cell viability, proliferation, migration, and invasion but inhibited apoptosis in ESCC. Moreover, luciferase reporter assay demonstrated that miR-624-3p bound to the 3'-untranslated region of phosphatase and tensin homologue (PTEN). Further study showed that miR-624-3p exerted its tumor promoting role through targeting PTEN. Taken together, these results elucidate the regulatory role of miR-624-3p in ESCC progression, shedding light on its possible clinical application in ESCC treatment.

LncRNA SNHG6 Inhibits Apoptosis by Regulating EZH2 Expression via the Sponging of MiR-101-3p in Esophageal Squamous-Cell Carcinoma.

BackgroundThe long non-coding RNA (lncRNA) SNHG6 was significantly upregulated in esophageal squamous-cell carcinoma (ESCC), and it promoted ESCC cell proliferation, invasion, and migration. However, the effects of SNHG6 on cell apoptosis and the corresponding underlying mechanisms have not yet reported.MethodsApoptosis was detected by flow cytometric analysis. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were used for mRNA and protein quantification, respectively. A luciferase reporter assay was performed to verify downstream target genes for SNHG6 and miR-101-3p.ResultsDysregulation of SNHG6 inhibited apoptosis in ESCC cells and regulated the expression of apoptosis-related proteins such as Bcl-2, Mcl-1, Bax and Caspase-3. Functionally, miR-101-3p could compete binding with 3′-untranslated region of SNHG6 and downregulation of miR-101-3p reversed its effect on cell apoptosis in SNHG6 knockdown cells. EZH2 was confirmed as a downstream target gene of miR-101-3p, silencing EZH2 expression had the same effect on apoptosis and protein expression as knocking down SNHG6. Overexpression of EZH2 reversed the effects of miR-101-3p overexpression on cell apoptosis in ESCC cells.ConclusionIn this study, we found that upregulation of the lncRNA SNHG6 inhibited apoptosis via miR-101-3p/EZH2 axis in ESCC. These findings may contribute to the diagnosis and treatment of ESCC.

Exosomal lncRNA FAM225A accelerates esophageal squamous cell carcinoma progression and angiogenesis via sponging miR-206 to upregulate NETO2 and FOXP1 expression.

Esophageal cancer is one of the leading causes of cancer‐related deaths worldwide. FAM225A is a novel lncRNA, only has been explored in nasopharyngeal carcinoma tumorigenesis. This study aims to investigate the regulatory mechanism of FAM225A in esophageal squamous cell carcinoma (ESCC). We discovered that FAM225A exhibited higher expression in ESCC. The silence of FAM225A attenuated cell viability, migration, and invasion, but facilitated cell apoptosis in ESCC. Exosome‐mediated transfer of lncRNA FAM225A could participate in ESCC progression. In addition, we found that miR‐206 bound to FAM225A. Moreover, we further demonstrated that FAM225A absorbed miR‐206 to upregulate NETO2 and FOXP1 expression, and FOXP1 acted as a transcription factor to enhance FAM225A expression. Eventually, it was revealed that the overexpression of NETO2 or FOXP1 rescued the effects of FAM225A repression on ESCC progression. Our results suggested that FAM225A upregulated NETO2 and FOXP1 expression by sponging miR‐206 to accelerate ESCC progression and angiogenesis. These results determined the biological role of lncRNA FAM225A in ESCC tumorigenesis, and FAM225A may be a promising biomarker for ESCC treatment.

MiR-199a-3p suppresses progression of esophageal squamous cell carcinoma through inhibiting mTOR/p70S6K pathway.

Dysregulation of microRNA contributes to multiple tumorigenic processes. Although downregulation of miR-199a-3p has been shown in many cancers, its effects on esophageal squamous cell carcinoma (ESCC) and the regulatory mechanism are still obscure. Here, we aim to evaluate the biological function and underlying mechanisms of miR-199a-3p in ESCC as well as its value to clinical treatment of ESCC. We first analyzed expression of miR-199a-3p in esophageal cancer by bioinformatic analysis and found that there were different opinions about expression of miR-199a-3p in esophageal cancer, and the following qRT-PCR assay demonstrated which was markedly downregulated in ESCC cells. Next, we increased the expression of miR-199a-3p in ESCC cells using miR-199a-3p mimics and demonstrated that overexpression of miR-199a-3p significantly inhibited cell proliferation, migration and invasion, as well as induced cell cycle retard and promoted apoptosis in ESCC. Furthermore, we explored the functional targets of miR-199a-3p and identified that overexpression of miR-199a-3p inhibited mTOR/p70S6K pathway, but stimulated PI3K/Akt pathway. Finally, we demonstrated that overexpression of miR-199a-3p enhanced proliferation-inhibiting effects of MK2206, an inhibitor of Akt, to ESCC cells, which might be related that MK2206 eliminated the activation of miR-199a-3p to p-Akt. These findings discover that miR-199a-3p might participate in the carcinogenesis process of ESCC, which provides a new insight for treatment of ESCC.

ZFPM2-AS1 facilitates cell growth in esophageal squamous cell carcinoma via up-regulating TRAF4.

Emerging evidence has confirmed that long noncoding RNAs (lncRNAs) are strongly involved in tumor initiation and development. LncRNA ZFPM2 antisense RNA 1 (ZFPM2-AS1) has been identified as a tumor facilitator in some cancers; nevertheless, its functional significance and regulatory mechanism remain greatly unclear in esophageal squamous cell carcinoma (ESCC). Here, we detected ZFPM2-AS1 expression in ESCC cell lines using qRT-PCR. ZFPM2-AS1 knockdown models were established for investigating the biological function of ZFPM2-AS1 in ESCC cells. The association between miR-3612 and ZFPM2-AS1 or TRAF4 was assessed by RNA pull-down and luciferase reporter assays. The present study indicated that ZFPM2-AS1 was significantly up-regulated in ESCC cells. Functional assays manifested that ZFPM2-AS1 knockdown restrained cell proliferation, migration and invasion, and facilitated cell apoptosis in ESCC. Mechanistically, ZFPM2-AS1 promoted ESCC cell growth and up-regulated TRAF4 to trigger NF-κB pathway by sequestering miR-3612. Besides, miR-3612 was confirmed to be a tumor inhibitor in ESCC. Through restoration experiments, we observed that TRAF4 overexpression could recover the suppressive effect of ZFPM2-AS1 on ESCC cell growth. Collectively, all the results suggested that ZFPM2-AS1 was an oncogene in ESCC cell growth by up-regulating TRAF4 and activating NF-κB pathway.

LncRNA-IUR up-regulates PTEN by sponging miR-21 to regulate cancer cell proliferation and apoptosis in esophageal squamous cell carcinoma.

Imatinib-up-regulated lncRNA (lncRNA-IUR) is a recently identified tumor suppressor, while its role in ESCC is unknown. This study aimed to investigate the role of lncRNA-IUR in esophageal squamous cell carcinoma (ESCC). Between April 2011 and April 2014, the Second Hospital of Jilin University admitted a total of 98 ESCC patients, from whom the present study selected 50 cases (33 males and 17 females; 43-67years; 54.8 ± 6.0year). ESCC cells and transient transfections, qPCR, RNA interaction analysis, western blot, CCK-8 assay, and cell apoptosis analysis were applied. We found that IUR was down-regulated in ESCC, and low levels of IUR predicted poor survival of ESCC patients. In ESCC cells, IUR expression levels were significantly and positively correlated with PTEN mRNA. Bioinformatics analysis showed that IUR may sponge miR-21, which can target PTEN. In ESCC cells, IUR over-expression led to the increased expression levels of PTEN; while miR-21 over-expression led to decreased expression levels of PTEN. IUR and miR-21 failed to affect each other. Cell proliferation and apoptosis analysis showed that IUR and PTEN over-expression inhibited cancer cell proliferation and promoted apoptosis; while miR-21 over-expression played an opposite role. In addition, miR-21 over-expression attenuated the effects of IUR over-expression on PTEN expression and cell proliferation. Therefore, IUR may up-regulate PTEN by sponging miR-21 to regulate cancer cell proliferation and apoptosis in ESCC.

MiRNA-574-5p downregulates ZNF70 and influences the progression of human esophageal squamous cell carcinoma through reactive oxygen species generation and MAPK pathway activation.

There is growing evidence shown that microRNAs (miRNAs) are associated with cancer and can play a role in human cancers as oncogenes or tumor suppressor genes. miRNA-574-5p is a candidate oncogene in various types of cancer, but little is known about biological functions of miR-574-5p in esophageal squamous cell carcinoma (ESCC). In this study, we observe that the expression of miR-574-5p is not only increased in human ESCC tissues but also remarkably increased in cell lines correlates with ZNF70. In vitro, we explored the role of miR-574-5p in ESCC progression via transfection of the miR-574-5p inhibitor into ECA-109 cells. The results show miR-574-5p serve as a tumor promoter regulating cells proliferation and apoptosis in ESCC through mitochondrial-mediated reactive oxygen species (ROS) generation and MAPK pathways. Furthermore, ZNF70 has been proved to as a functional target for miR-574-5p to regulate cells poliferation and apoptosis. In summary, these results suggest that miR-574-5p serves as tumor promoter to promote proliferation and inhibit apoptosis of ESCC cells by targeting ZNF70 via mitochondrial-mediated ROS generation and MAPK pathways. The miR-574-5p/ZNF70 pathway provides a new insight into the molecular mechanisms that the occurrence and development of ESCC and it provides a novel therapeutic target for ESCC.

LncRNA KLF3-AS1 Suppresses Cell Migration and Invasion in ESCC by Impairing miR-185-5p-Targeted KLF3 Inhibition

Esophageal squamous cell carcinoma (ESCC) is a common cancer occurring in males and females worldwide. Accumulating evidence continues to highlight the crucial roles of long non-coding RNAs (lncRNAs) in the process of tumorigenesis. However, the regulatory mechanism of lncRNAs in ESCC remains unclear. The aim of this study is to elucidate the role of lncRNA Krüppel-like factor 3 antisense RNA 1 (KLF3-AS1) in ESCC by regulating miR-185-5p and KLF3. Initially, ESCC cell spheres with stem cell-like properties were prepared by suspension culture, and subsequently characterized by assessing colony formation ability and stem cell markers. LncRNA KLF3-AS1 was found to be poorly expressed in ESCC and could upregulate the expression of KLF3 by binding to miR-185-5p. lncRNA KLF3-AS1 upregulation was observed to inhibit miR-185-5p, thereby contributing to decreased expression of SOX2 and Oct4 (octamer-binding transcription factor 4). Furthermore, enhancement of lncRNA KLF3-AS1 resulted in reduced colony formation ability, cell invasion and migration, and tumor volume in vivo while promoting cell apoptosis in ESCC through downregulation of miR-185-5p. Collectively, this study indicated that lncRNA KLF3-AS1 inhibited ESCC cell invasion and migration by impairing miR-185-5p-mediated inhibition of KLF3, highlighting a promising novel potential target for ESCC treatment.

Combination of the natural compound Periplocin and TRAIL induce esophageal squamous cell carcinoma apoptosis in vitro and in vivo: Implication in anticancer therapy

BackgroundEsophageal cancer is one of the most common malignant tumors in the world. With currently available therapies, only 20% ~ 30% patients can survive this disease for more than 5 years. TRAIL, a natural ligand for death receptors that can induce the apoptosis of cancer cells, has been explored as a therapeutic agent for cancers, but it has been reported that many cancer cells are resistant to TRAIL, limiting the potential clinical use of TRAIL as a cancer therapy. Meanwhile, Periplocin (CPP), a natural compound from dry root of Periploca sepium Bge, has been studied for its anti-cancer activity in a variety of cancers. It is not clear whether CPP and TRAIL can have activity on esophageal squamous cell carcinoma (ESCC) cells, or whether the combination of these two agents can have synergistic activity.MethodsWe used MTS assay, flow cytometry and TUNEL assay to detect the effects of CPP alone or in combination with TRAIL on ESCC cells. The mechanism of CPP enhances the activity of TRAIL was analyzed by western blot, dual luciferase reporter gene assay and chromatin immunoprecipitation (ChIP) assay. The anti-tumor effects and the potential toxic side effects of CPP alone or in combination with TRAIL were also evaluated in vivo.ResultsIn our studies, we found that CPP alone or in combination with TRAIL could inhibit the proliferation of ESCC cells and induce apoptosis, and we certificated that combination of two agents exert synergized functions. For the first time, we identified FoxP3 as a key transcriptional repressor for both DR4 and DR5. By down-regulating FoxP3, CPP increases the expression of DR4/DR5 and renders ESCC cells much more sensitive to TRAIL. We also showed that CPP reduced the expression of Survivin by inhibiting the activity of Wnt/β-catenin pathway. All these contributed to synergistic activity of CPP and TRAIL on ESCC cells in vitro and in vivo.ConclusionOur data suggest that CPP and TRAIL could be further explored as potential therapeutic approach for esophageal cancer.

Discovery of indoline derivatives that inhibit esophageal squamous cell carcinoma growth by Noxa mediated apoptosis

A series of novel indoline derivatives were synthesized and evaluated for antiproliferative activity against four selected cancer cell lines (Hela, A549, HepG2 and KYSE30). Among them, compound 20 displayed the potent inhibition activity against esophageal cancer cells (Kyse30, Kyse450, Kyse510 and EC109). Cellular mechanism studies in esophageal squamous cell carcinoma (ESCC) cells elucidated compound 20 inhibited cell growths in vitro and in vivo, reduced colony formation, arrested cell cycle at M phase, and induced Noxa-dependent apoptosis in ESCC. Importantly, compound 20 was identified as a novel Noxa mediated apoptosis inducer. These results suggested that compound 20 might be a promising anticancer agent with potential for development of further clinical applications.