Proliferation Of Esophageal Squamous Cell Carcinoma Research Articles

LINC00963 predicts poor prognosis and promotes esophageal cancer cells invasion via targeting miR-214-5p/RAB14 axis.

To explore the roles and underlying mechanism of LINC00963 in esophageal squamous cell carcinoma (ESCC) progression. Quantitative Real Time-PCR (qRT-PCR) was used to detect LINC00963 expression in ESCC tissues. EdU, colony formation, and transwell invasion assays were used to detect the proliferation and metastasis ability of ESCC, respectively. The correlation between LINC00963 and miR-214-5p in ESCC was confirmed by a Luciferase reporter and RIP assays. LINC00963 expression was significantly increased in ESCC tissues and correlated with advanced TNM stage, metastasis, and poor prognosis. The knockdown of LINC00963 expression reduced ESCC cells proliferation, invasion in vitro, and reduced tumor growth in vivo. In mechanism, LINC00963 served as a sponge for miR-214-5p in ESCC progression. In addition, miR-214-5p could bind to RAB14 and regulate its expression. LINC00963 might promote ESCC cells proliferation and invasion via regulating the miR-214-5p/RAB14 axis and it might serve as a therapeutic target for ESCC treatment.

MiR-125b suppresses cell proliferation and metastasis by targeting HAX-1 in esophageal squamous cell carcinoma

•MicroRNAs (miRNAs) function as crucial regulators of various cancers. miR-125b acts as a tumor suppressor in multiple types of cancers. The aim of this study was to assess the role and molecular mechanism of miR-125b in esophageal squamous cell carcinoma (ESCC). Quantitative real-time PCR was used to quantify miR-125b expression. Luciferase reporter assay was conducted to confirm HAX-1 3′UTR associations. In addition, the function of miR-125b and HAX-1 in ESCC was detected using MTT and transwell assays. We found that miR-125b was dramatically down-regulated in ESCC tissues and cell lines. Functional assays showed that over-expression of miR-125b suppressed ESCC cell proliferation and migration in vitro. On the contrary, cell proliferation and migration were promoted by miR-125b inhibition. Moreover, our results demonstrated that miR-125b markedly reduced the expression and transcription activity of HAX-1. HAX-1 expression reversed the miR-125b-induced suppression of cell proliferation and migration. Our data identify that down-regulation of miR-125b suppressed cell proliferation and migration of ESCC through up-regulating HAX-1 expression.

CDK14 involvement in proliferation migration and invasion of esophageal cancer.

CDK14 has significant involvement in tumorigenesis of cancers including hepatocellular carcinoma, gastric carcinoma and breast cancer. In esophageal cancer, CDK14 is useful as a prognostic marker and as a predictor of response to chemotherapy. However, the exact mechanism of CDK14 n chemotherapy for esophageal squamous cell carcinoma (ESCC) has not been explored. Western blots and immunohistochemistry (IHC) analysis were performed to analyse the expression of CDK14 in ESCC. Co-immunoprecipitation and immunofluorescence assays were used to explore the mechanism of CDK14 involvement in ESCC. Colony formation assays and proliferation assays were used to investigate the function of CDK14 in ESCC. At last, we constructed two truncated mutants of CDK14 by the PCR technology to research the functional structural domain. Western blots and IHC analysis showed that CDK14 expression was higher n tumor tissues and cell lines than that in normal tissues. IHC staining revealed that CDK14 positively correlated with clinical pathological variables of tumor size (P=0.001), tumor grade (P=0.004), Ki-67 (P=0.012) and survival (P=0.000). Immunoprecipitation and immunofluorescence assays revealed that CDK-activating kinase (CAK), namely CDK7/CCNH complex physically interacted and was collocated with CDK14 in the cell nucleus. This direct interaction increased CDK14 phosphorylation and inhibited Rb function through phosphorylation. In vitro starvation and refeeding assays demonstrated that CDK14 expression was related to proliferation of ESCC cells. Overexpression of CDK14 in Eca109 cells increased colony formation and reduced sensitivity to cisplatin. Overexpressing CDK7 with CDK14 strengthened these effects, demonstrating that CDK7 was a major component in CDK14 activation. Expression of CDK14 worsened the effects of cisplatin chemotherapy by promoting ESCC proliferation.

Long Non-Coding RNA LINC00152 Regulates Cell Proliferation, Migration And Invasion In Esophageal Squamous Cell Carcinoma Via miR-107/Rab10 Axis.

BackgroundEsophageal squamous cell carcinoma (ESCC) is a common malignant tumor in East Asia. Emerging evidence indicated that long intergenic non-coding RNA 152 (LINC00152) acts as an oncogene in many types of cancers including ESCC. This study aims to identify the biological mechanisms of LINC00152 in ESCC, hinting for new therapeutic target for ESCC patients.MethodsThe levels of LINC00152, microRNA-107 (miR-107) and Ras-related protein Rab-10 (Rab10) were measured in ESCC tissues and cells using qRT-PCR. The protein level of Rab10 was measured by Western blot assay. The putative target of LINC00152 or miR-107 was searched using starBase v2.0 and TargetScan online databases, and dual-luciferase reporter assay was conducted to detect the interaction between miR-107 and LINC00152 or Rab10. The cell viability was monitored by CCK8 assay, and the abilities of migration and invasion were assessed by Transwell assay, respectively. The mice model experiments were constructed to affirm the biological role of LINC00152 in vivo.ResultsLINC00152, Rab10 was significantly upregulated, and miR-107 was strikingly down-regulated in ESCC tissues and cell lines (TE-1 and KYSE30). LINC00152 was verified as a sponge for miR-107, and Rab10 was a direct target of miR-107. LINC00152 depletion decreased cell viability and abilities of migration and invasion by regulating miR-107 in vitro and blocked xenograft tumor growth in vivo. The overexpression of miR-107 reduced cell viability and the abilities of migration and invasion by modulating Rab10. LINC00152 positively regulated Rab10 expression by sponging miR-107.ConclusionIn this study, we found that LINC00152 modulated Rab10 to promote cell proliferation, migration and invasion in ESCC by sponging miR-107. This new regulatory network may provide a novel therapeutic target for ESCC patients.

MiR-204-5p regulates cell proliferation, invasion, and apoptosis by targeting IL-11 in esophageal squamous cell carcinoma.

Esophageal cancer (EC) is the world's eighth most common malignant neoplasm and is ranked as the sixth leading cause of death related to cancer. Aberrant microRNA (miRNA) expression has been reported to be associated with esophageal squamous cell carcinoma. However, the molecular mechanism of miR-204-5p in esophageal squamous cell carcinoma (ESCC) is not clear. Therefore, the aim of this study was to investigate the potential role of miR-204-5p in ESCC. In the present study, we found that miR-204-5p could affect ESCC proliferation, invasion, apoptosis, and cell cycle in cell and mouse models. A dual-luciferase reporter assay showed that miR-204-5p expression was negatively correlated with interleukin-11 (IL-11) expression. IL-11 overexpression reversed the suppressive effects of miR-204-5p in the cell lines. These results indicated that miR-204-5p functions as a tumor suppressor by directly targeting IL-11 in ESCC.

CLDN1 induces autophagy to promote proliferation and metastasis of esophageal squamous carcinoma through AMPK/STAT1/ULK1 signaling.

Tight junction is a structural constitution in cell-cell adhesion and play an important role in the maintenance of permeability and integrity of normal epithelial cell barrier. The protein encoded by Claudin 1 (CLDN1), a member of the claudin family, is an integral membrane protein and a component of tight junction strands. CLDN1 has been proved to regulate the proliferation and metastasis of multiple tumors, but little is known about its role in esophageal squamous cell carcinoma (ESCC). Here, we found that CLDN1 was aberrantly increased in ESCC tissues and cell lines, and mainly distributed in the nucleus of tumor cells. Furthermore, we confirmed that CLDN1 promoted the proliferation and metastasis of ESCC by triggering autophagy both in vitro and in vivo. Mechanically, we validated that CLDN1-induced autophagy via increasing Unc-51 like autophagy activating kinase 1 (ULK1) expression through AMP-activated protein kinase (AMPK)/signal transducer and activator of transcription 1 (STAT1) signaling pathway in ESCC cells. Taken together, our findings demonstrated that aberrant expression and distribution of CLDN1 promoted the proliferation and metastasis of esophageal squamous carcinoma by triggering autophagy through AMPK/STAT1/ULK1 signaling pathway.

RETRACTED: MicroRNA-134 prevents the progression of esophageal squamous cell carcinoma via the PLXNA1-mediated MAPK signalling pathway

BackgroundMicroRNAs (miRNAs) are involved in oncogenesis of esophageal squamous cell carcinoma (ESCC). miR-134 is reported to have a tumour-suppressive role but its role in ESCC is not known. The present study was designed to examine whether miR-134 inhibits ESCC development and further explored relevant underlying mechanisms.MethodsDifferentially expressed genes related to ESCC were identified from microarray gene expression profiles. Immunohistochemical staining and RT-qRCR assays identified elevated PLXNA1 expression levels and low miR-134. The relationship between miR-134 and PLXNA1 was predicted and further verified by a dual-luciferase reporter assay. The expression levels of miR-134 and PLXNA1 in ESCC cells were modified by miR-134 mimic/inhibitor and siRNA against PLXNA1, respectively. Thereafter, the expression of MAPK signalling pathway-related proteins, as well as the viability, migration, invasion, cell cycle and cell apoptosis of ESCC cells was investigated.FindingsThe results showed that miR-134 could block the MAPK signalling pathway by downregulating PLXNA1. When miR-134 was overexpressed or PLXNA1 was silenced, cell apoptosis was enhanced, the cell cycle was retarded, and the cell proliferation, migration and invasion were suppressed. In vivo experiments confirmed that miR-134 overexpression or PLXNA1 silencing restrained tumour growth and lymph node metastasis.InterpretationThese findings demonstrate that cancer cell proliferation, migration, invasion, and tumour metastasis of ESCC can be suppressed by overexpression of miR-134 through downregulating PLXNA1, which subsequently blocks the MAPK signalling pathway. These results provide new potential targets and strategies for the treatment of ESCC.

Epigenetically Upregulated MicroRNA-602 Is Involved in a Negative Feedback Loop with FOXK2 in Esophageal Squamous Cell Carcinoma.

MicroRNA is an endogenous, small RNA controlling multiple target genes and playing roles in various tumorigenesis processes. In this study, our results revealed that miR-602 expression levels in tumor tissues and preoperative serum from esophageal squamous cell carcinoma (ESCC) patients were higher than those in non-tumorous tissues and healthy volunteers. miR-602 overexpression was closely related to lymph node metastasis and TNM stages and correlated short overall, and it acted as an independent prognostic marker of ESCC. The methylation status of the miR-602 gene indicated more frequent hypomethylation of the CpG sites located upstream of the miR-602 gene in the ESCC tissues than in the adjacent normal tissues, and the methylation status of miR-602 correlated inversely with its expression levels. Subsequently, miR-602 overexpression promoted ESCC proliferation and metastasis and regulated cell cycles invitro and invivo. Mechanistically, a dual-luciferase experiment validated that Fork head box (FOX)K2 (FOXK2) was a direct target of miR-602. More importantly, systemic delivery of formulated miR-602 antagomir could reduce tumor growth and increased FOXK2 protein expression in nude mice. This work provides novel insight into the molecular pathogenesis of ESCC.

MicroRNA-488-3p inhibits proliferation and induces apoptosis by targeting ZBTB2 in esophageal squamous cell carcinoma.

Esophageal squamous cell carcinoma (ESCC) is the eighth most prevalent cancer and the sixth leading cause for cancer-associated mortality. MicroRNAs (miRNAs) are increasingly reported to exert important regulatory functions in human cancers by regulating certain gene expression. miR-488-3p has been identified to be a tumor suppressor in multiple cancers, but its role in ESCC is yet to be investigated. The present study aimed to uncover the biological role and modulatory mechanism of miR-488-3p in ESCC. We first revealed the downregulation of miR-488-3p in ESCC tissues and cell lines. Gain-of-function assays confirmed that miR-488-3p overexpression abrogated proliferation and accelerated apoptosis. Mechanistically, we identified via bioinformatics tool and confirmed that zinc finger and BTB domain containing 2 (ZBTB2) was a target for miR-488-3p. Moreover, miR-488-3p activated the p53 pathway through suppressing ZBTB2. Finally, rescue assays proved that ZBTB2 was involved in the regulation of miR-488-3p on proliferation and apoptosis in ESCC. Additionally, we verified that miR-488-3p had alternate targets in ESCC by confirming the involvement of protein kinase, DNA-activated, catalytic subunit (PRKDC), a known target for miR-488-3p, in miR-488-3p-mediated regulation on ESCC. In sum, this study revealed that miR-488-3p inhibited proliferation and induced apoptosis by targeting ZBTB2 and activating p53 pathway in esophageal squamous cell carcinoma, providing a novel biological target for ESCC.

SP promotes cell proliferation in esophageal squamous cell carcinoma through the NK1R/Hes1 axis

BackgroundSubstance P (SP) plays an important role in several types of cancer promotion and progression by binding to its preferential neurokinin 1 receptor (NK1R). However, the clinical significance and downstream mechanism of NK1R in esophageal squamous cell carcinoma (ESCC) have not been elucidated. The aim of this study was to investigate the role of SP/NK1R in the proliferation of ESCC and to screen related downstream molecules. MethodsIn the current investigation, the expression of NK1R was detected via immunohistochemistry (IHC), western blot (WB) analysis and real-time reverse transcription-polymerase chain reaction (RT-qPCR) in ESCC tissues and cell lines. Thereafter, the optimal concentration of SP was determined in vitro. The proliferation ability of SP/NK1R was assessed by cell counting kit-8 (CCK-8) and colony formation assays and subcutaneous tumour formation in nude mice with EC109 cells. Moreover, the related downstream molecules were screened by performing isobaric tags for relative and absolute quantitation (iTRAQ) protein spectrum analysis. ResultsNK1R was upregulated in ESCC, and its overexpression correlated with larger tumour size, deeper tumour invasion, more perineural invasion and eventually caused poorer overall survival (OS). Both intrinsic and SP-activated NK1R upregulation could promote the proliferation and clonogenic capacity of ESCC cells. In nude mice, tumour growth was suppressed by EC109 cells of NK1R downregulation. Further experiments demonstrated that Hairy and Enhancer of Split 1 (Hes1) was markedly reduced upon NK1R downregulation in EC109 cell lines and could regulate cell proliferation in the downstream of SP/NK1R. ConclusionsThe significant role of NK1R in mediating ESCC cell proliferation depended on the activation of SP and might be related to the downstream regulation of Hes1.

MDM2 and its functional polymorphism SNP309 contribute to the development of esophageal carcinoma.

Overexpression of the murine double minute 2 (MDM2) has been explored in many tumors with high proliferation and anti-apoptosis ability. However, the role of MDM2 and its functional single nucleotide polymorphism (SNP) rs2279744 (also known as SNP309) in esophageal squamous cell carcinoma (ESCC) remains unclear. We performed a genotype study of blood samples in 360 ESCC patients and 360 healthy control individuals to determine the risk of various rs2279744 in ESCC. To further evaluate the role of rs2279744 in regulating MDM2 expression, we performed an allele-specific reporter assay and investigated whether the SNP-containing sequences functioned as an active enhancer. To examine the functional role of MDM2 on esophageal cancer cell lines, we carried out an MTS assay and flow cytometry analysis. From the genotyping study, we found that GG genotype of SNP309 significantly increased the risk of ESCC in an additive model [odds ratio (OR)=2.55, 95% confidence interval (CI)=1.66-3.89, p=1.50×10-5 ) and in a recessive model (OR=2.44, 95% CI=1.69-3.51, p=1.60×10-8 ). Furthermore, the G allele was significantly associated with a higher risk of ESCC (OR=1.56, 95% CI=1.26-1.92, p=2.81×10-5 ). In multivariate logistic regression analysis, the GG genotype had increased the occurrence of ESCC by 2.39-fold (95% CI=1.48-3.8). Compared to the T allele, the variant G allele had significantly higher luciferase activity on the promoter of MDM2 in both cell lines. By transfecting the gene to ESCC lines, we showed that overexpression of MDM2 significantly promote cell proliferation and anti-apoptosis. The MDM2 promoter SNP309 is a risk factor for esophageal cancer. MDM2 promotes the proliferation and anti-apoptosis of ESCC.

Upregulation of a novel lncRNA LINC01980 promotes tumor growth of esophageal squamous cell carcinoma

An increasing number of long noncoding RNAs (lncRNAs) have been discovered, and dysregulation of lncRNAs plays critical roles in tumorigenesis and tumor progression. In this study, we identified a novel lncRNA LINC01980, located in both the cytoplasm and nucleus, which was significantly upregulated in esophageal squamous cell carcinoma (ESCC) tissues through microarray profiling. Further analysis revealed that LINC01980 overexpression was positively correlated with deeper invasion of cancer, positive lymph node metastasis, and advanced TNM stage. Additionally, high LINC01980 expression in ESCC tissues was associated with poor prognosis. In vitro and in vivo experiments demonstrated that LINC01980 promoted ESCC growth. EdU incorporation assay implied that LINC01980 accelerated ESCC proliferation. Flow cytometry analysis showed that knockdown of LINC01980 induced cell cycle arrest and increased apoptosis. Microarray analysis indicated that LINC01980 upregulated the expression of growth arrest and DNA damage inducible 45 alpha (GADD45A). Further experiments demonstrated that GADD45A promoted ESCC cell growth, indicating that GADD45A may be a downstream target of LINC01980. In conclusion, this study identified LINC01980 as a novel potential oncogene in ESCC, which can be a promising biomarker for prognosis and therapeutic targeting in ESCC.

CDK11p110 plays a critical role in the tumorigenicity of esophageal squamous cell carcinoma cells and is a potential drug target

ABSTRACT Esophageal squamous cell carcinoma (ESCC) is a serious malignancy with limited options for targeted therapy. The exploration of novel targeted therapies for combating ESCC is urgently needed. Cyclin-dependent kinases (CDKs) play important roles in the progression of cancers; however, the function of CDK11p110 (cyclin-dependent kinase 11p110) in ESCC is still unknown. Here, we investigated the effects and molecular mechanisms of CDK11p110 in the proliferation and growth of ESCC by examining the expression of CDK11p110 in ESCC tissues and by detecting phenotypic changes in ESCC cells after CDK11p110 knockdown or overexpression in vitro and in vivo. According to the tissue microarray analysis, compared with its expression level in normal tissues, the expression level of CDK11p110 was significantly elevated in ESCC tissues; this result was in concordance with the data in TCGA (The Cancer Genome Atlas) datasets. In addition, RNAi-mediated CDK11p110 silencing exerted a substantial inhibitory effect on the proliferation, clonogenicity and migration ability of ESCC cells. Further study indicated that CDK11p110 knockdown arrested ESCC cells in the G2/M phase of the cell cycle and induced cell apoptosis. Moreover, stable shRNA-mediated CDK11p110 knockdown inhibited tumor growth in an ESCC xenograft model, and overexpression of CDK11p110 enhanced tumor growth. In addition, the Ki67 proliferation index was closely associated with the elevation or depletion of CDK11p110 in vivo. In summary, this study provides evidence that CDK11p110 play a critical role in the tumorigenicity of ESCC cells, which suggests that CDK11p110 may be a promising therapeutic target in ESCC. Abbreviations: CDKs: cyclin-dependent kinases; CDK11: Cyclin-dependent kinase 11; CDK11p110: Cyclin-dependent kinase 11p110, the larger isomer of cyclin-dependent kinase 11; ESCC: esophageal squamous cell carcinoma; FACS: fluorescence-activated cell sorting; FDA: the Food and Drug Administration; TCGA: The Cancer Genome Atlas; TMA: tissue microarray.

Up-regulation of circ-SMAD7 inhibits tumor proliferation and migration in esophageal squamous cell carcinoma

BackgroundIncreasing evidences demonstrate that circular RNAs (circRNAs) play an important role in the development and progression of human cancers. Nevertheless, the functions and molecular mechanism of circRNAs in esophageal squamous cell carcinoma (ESCC) tumorigenesis are largely unknown. The purpose of this research is to investigate the expression and potential role of a new circular RNA named circ-SMAD7 on ESCC carcinogenesis. Materials and methodsQuantitative real-time polymerase chain reaction (qRT-PCR) was used to measure circ-SMAD7 expression amount in both ESCC plasmas and tissues. Then the correlation between the expression of circ-SMAD7 and clinicopathological features was analyzed. Furthermore, by loss-of-function and gain-of-function experiments in ESCC cells, a functional analysis of circ-SMAD7 on ESCC cell proliferation and migration was performed. ResultsThe expression of circ-SMAD7 was validated to be significantly down-regulated in ESCC plasmas in comparison with normal controls, showing a high negative correlation with TNM stage (P = 0.000) and lymphatic metastasis (P = 0.000). Moreover, circ-SMAD7 was significantly down-regulated in ESCC tissues compared to adjacent normal tissues. Furthermore, Loss-of-function and gain-of-function experiments revealed that the expression level of circ-SMAD7 affected the proliferation and migration of ESCC cell lines. ConclusionOur study firstly exposed that over-expressioncirc-SMAD7, an influential regulator in cancer progression, can inhibit tumor proliferation and migration in ESCC and have the potential of becoming a biomarker for the diagnosis and therapy of ESCC.

MiR-25 mediates metastasis and epithelial–mesenchymal-transition in human esophageal squamous cell carcinoma via regulation of E-cadherin signaling

ABSTRACT MiR-25 is a well-documented oncogenic miRNA implicated in esophageal squamous cell carcinoma (ESCC) development, progression and metastasis. However, whether and how miR-25 is involved in the development and metastasis of ESCC remain un-addressed. By using qRT-PCR analysis to compare levels of miR-25 in ESCC tissues with or without lymph node metastasis (LNM), it showed that ESCC tissues with LNM had increased levels of miR-25, which was correlated with tumor metastasis and poor prognosis. Gain- and loss-of-function assays indicated that targeting miR-25 could reverse EMT, and reduce in vitro cell migration and invasion, but not apoptosis and proliferation of ESCC. Furthermore, targeting miR-25 inhibited in vivo lung metastasis, and vice versa. And E-cadherin was a direct target of miR-25 through which affected EMT process and metastasis of ESCC. It is therefore indicated that miR-25 promotes metastasis of ESCC through E-cadherin and EMT events, thus may serves as a negative prognostic factor and possible target for treatment of ESCC patients.

Overexpression of TAF1L Promotes Cell Proliferation, Migration and Invasion in Esophageal Squamous Cell Carcinoma.

Currently, it reported that TAF1L gene mutation is found in a number of carcinomas, but its pathophysiological function has not been well studied. We focused on investigating expressive levels of TAF1L gene and protein in esophageal squamous cell carcinoma (ESCC) with two tissue microarrays, forty fresh paired ESCC and paracancer samples using immunohistochemistry, real-time PCR or Western blot in this study. Furthermore, we executed TAF1L silence with siRNA in ESCC cell lines to evaluate effects of TAF1L expression on cell proliferation, migration and invasion of ESCC via CCK-8, wound healing and transwell chamber assays. Moreover, key proteins related to ESCC development were also analyzed by Western blot. Results from this study showed that the expression of TAF1L mRNA and protein in ESCC tissues were significantly higher than that in matched paracancer tissues. However, its abnormal expression was not associated with other clinic features, such as the age, gender and pathological grade, except of TNM-N stage. Furthermore, the proliferation, migration and invasion of ESCC cells were inhibited after TAF1L gene silencing. As a consequence, the expression of c-Myc and phosphorylated Akt in esophageal squamous cell line after TAF1L-siRNA treatment were inversely decreased, while p53 was increased significantly, compared those to control group. Taken together, the results from this study suggest that TAF1L gene might be served as an oncogene, and its overexpression could accelerate to the tumorigenesis of ESCC via promoting the malignant cell proliferation and tumor metastasis.

MicroRNA‑21 regulates the biological behavior of esophageal squamous cell carcinoma by targeting RASA1.

MicroRNA-21 (miR-21) has been revealed to play a crucial role in regulating the biological behavior, including proliferation, migration, invasion and metastasis in certain cancers. However, its role in esophageal squamous cell carcinoma (ESCC) has yet to be elucidated. Based on the data of GSE13937 downloaded from Gene Expression Omnibus (GEO) database, miR-21 was revealed to be one of the top 20 differentially expressed (DE) miRNAs screened using the Morpheus online tool. RAS p21 protein activator 1 (RASA1) was predicted as the target gene of miR-21 using the predicting software and was combined with miR-21 using the luciferase reporter assay. Its relative expression was significantly decreased, however, miR-21 was increased in the tumor tissues compared to the normal adjacent tissues in patients with ESCC as determined by quantitative polymerase chain reaction (q-PCR). Furthermore, overexpression of miR-21 (mimic) could significantly decrease the gene level of RASA1. Conversely, downregulation of miR-21 (inhibitor) significantly increased the gene level of RASA1, while downregulation of RASA1 (siRASA1) markedly increased the gene expression of miR-21. Notably, the expression of Snail and vimentin were significantly increased by upregulation of miR-21 and downregulation of RASA1. Transwell results revealed that miR-21 and RASA1 regulated proliferation, migration and invasion in ESCC cells. In an in vivo model, miR-21 inhibitor (antagomir) could inhibit tumor growth. In conclusion, miR-21 regulated cell proliferation, migration, invasion and tumor growth of ESCC by directly targeting RASA1, which may have been achieved via regulation of Snail and vimentin. Anti-miR-21 revealed an antitumor effect. Thus, it may be considered as a possible target for ESCC therapy.

MicroRNA-375 inhibits esophageal squamous cell carcinoma proliferation through direct targeting of SP1.

Several studies have shown that microRNA-375 (miR-375) is frequently downregulated in several types of human cancer including gastric cancer, colorectal cancer and oral squamous cell carcinoma. However, the role of miR-375 in human esophageal cancer remains unknown. In the current study, the expression level of miR-375 was analyzed in 43 esophageal squamous cell carcinoma (ESCC) tissue and matched adjacent normal tissue samples from patients with ESCC by reverse transcription-quantitative polymerase chain reaction. In addition, the expression level of miR-375 was analyzed in ESCC cell lines (KYSE450 and KYSE150) and the human esophageal epithelial cell line Het-1A by the same method. The expression level of miR-375 was significantly downregulated in ESCC tissue samples and cell lines compared with adjacent normal tissue samples and the human esophageal epithelial cell line, respectively. The effect of miR-375 on ESCC cell proliferation was detected by cell counting kit-8 (CCK-8) and colony formation assays. miR-375 overexpression significantly decreased ESCC cell proliferation and colony formation. Bioinformatics analysis was used to predict specificity protein 1 (SP1) as a target gene of miR-375 in ESCC, and this was verified by dual-luciferase assay. The present study demonstrated that SP1 regulates ESCC cell proliferation and colony formation through direct interaction with miR-375. In addition, the overall survival of patients with ESCC was analyzed using the Kaplan-Meier method and log-rank test. The results indicated that patients with ESCC with high miR-375 expression had a better survival rate compared with patients with ESCC with low miR-375 expression. Taken together, these results suggest that downregulated miR-375 promotes ESCC cell proliferation and colony formation via direct targeting of SP1, and this association may contribute to ESCC progression.

Promoter hypomethylation mediated upregulation of MicroRNA-10b-3p targets FOXO3 to promote the progression of esophageal squamous cell carcinoma (ESCC)

BackgroundEsophageal cancer is a high incident cancer worldwide with poor survival and limited therapeutic options. Alterations of microRNAs are common in cancers, and many of these micro RNAs are potential therapeutic and diagnostic targets to treat these cancers. miR-10b-3p located in chromosome region 2q31.1, and its expression is frequently increased in esophageal squamous cell carcinoma (ESCC). However, the biological functions, clinical significance and therapeutic implications of miR-10b-3p in ESCC remain unclear.MethodsThe expression levels of miR-10b-3p in ESCC specimens were analyzed by in situ hybridization (ISH) and quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. Ectopic overexpression of miR-10b-3p in ESCC cells, mouse xenograft model, and metastasis model were used to evaluate the effects of miR-10b-3p on proliferation, and migration of cancer cells. Luciferase reporter assay and Western blot were performed to validate the potential targets of miR-10b-3p after the preliminary screening by computer-aided microarray analysis.ResultsWe found that miR-10b-3p expression levels were significantly upregulated in the tumor tissues and serum samples of patients with ESCC. The expression levels of miR-10b-3p in both tumor tissues and serum samples were inversely associated with lymph node metastasis and clinical stages. We identified the expression level of miR-10b-3p in ESCC cancer samples as an independent prognostic marker of the overall survival rates of ESCC patients. We found more frequent hypomethylation of the CpG sites located upstream of the miR-10b-3p gene in the ESCC tissues compared with in the adjacent normal tissues, and the DNA methylation status of miR-10b-3p promoter region inversely correlated with the expression levels of miR-10b-3p. Ectopic overexpression of miR-10b-3p promoted cell proliferation, colony formation, migration and invasion in ESCC. While knockdown of miR-10b-3p had the opposite effects, particularly in promoting apoptosis. Mouse xenograft model confirmed that miR-10b-3p functions as a potent oncogenic miRNA in ESCC, which also promoting ESCC metastasis. Mechanistically, we found miR-10b-3p regulated FOXO3 expression by directly binding to the 3′-untranslated region. And systemic delivery of miR-10b-3p antagomir reduced tumor growth and inhibit FOXO3 protein expression in nude mice.ConclusionsCollectively, our findings suggested upregulated expression of miR-10b-3p caused by promoter hypomethylation contributed to the progression of ESCC; Thus, miR-10b-3p is a potentially effective biomarker for ESCC that could have further therapeutic implications.

MiR-490-3p inhibited the proliferation and metastasis of esophageal squamous cell carcinoma by targeting HMGA2.

To identify the potential role of miR-490-3p in the development of esophageal squamous cell carcinoma (ESCC), and to explore the possible underlying mechanism. Human ESCC tissues and cancer-adjacent normal tissues were collected. The mRNA expression level of miR-490-3p was detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). On-line target gene prediction software was applied to screen high-mobility group AT-hook 2 (HMGA2). Subsequently, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide), qRT-PCR, Western blotting, transwell and scratch-wound assays were conducted to analyze the effect of miR-490-3p on the biological function of the ESCC cell line (EC-109). In our study, the mRNA expression level of miR-490-3p was remarkably reduced in ESCC tissues and cells. Molecular mechanism analysis confirmed that miR-490-3p could act on the 3'-UTR of HMGA2 and regulate its expression. Subsequent functional experiments indicated that decreased expression of HMGA2 resulting from the up-regulation of miR-490-3p could inhibit the proliferation, invasion, migration and epithelial-mesenchymal transition (EMT) of ESCC cells. We discovered the inhibitory effect of miR-490-3p on ESCC by targeting HMGA2, and revealed that miR-490-3p could be a potential therapeutic target for ESCC.