Serum microRNA-15a level acts as a potential diagnostic and prognostic biomarker for human esophageal squamous cell carcinoma

Construction of a miR-15a-based risk prediction model for vascular calcification detection in patients undergoing hemodialysis

Vascular calcification (VC) is highly prevalent in patients undergoing hemodialysis, and is a significant contributor to the mortality rate. Therefore, biomarkers that can accurately predict the onset of VC are urgently required. Our study aimed to investigate serum miR-15a levels in relation to VC and to develop a predictive model for VC in patients undergoing hemodialysis at the Beijing Friendship Hospital hemodialysis center between 1 January 2019 and 31 December 2020. The patients were categorized into two groups: VC and non-VC. Logistic regression (LR) models were used to examine the risk factors associated with VC. Additionally, we developed an miR-15a-based nomogram based on the results of the multivariate LR analysis. A total of 138 patients under hemodialysis were investigated (age: 58.41 ± 13.22 years; 54 males). VC occurred in 79 (57.2%) patients. Multivariate LR analysis indicated that serum miR-15a, age, and WBC count were independent risk factors for VC. A miR-15a-based nomogram was developed by incorporating the following five predictors: age, dialysis vintage, predialysis nitrogen, WBC count, and miR-15a. The receiver operating characteristic (ROC) curve had an area under the curve of 0.921, diagnostic threshold of 0.396, sensitivity of 0.722, and specificity of 0.932, indicating that this model had good discrimination. This study concluded that serum miR-15a levels, age, and white blood cell (WBC) count are independent risk factors for VC. A nomogram constructed by integrating these risk factors can be used to predict the risk of VC in patients undergoing hemodialysis.

Cell-free RNA for the liquid biopsy of gastrointestinal cancer

Gastrointestinal (GI) cancer includes many cancer types, such as esophageal, liver, gastric, pancreatic, and colorectal cancer. As the cornerstone of personalized medicine for GI cancer, liquid biopsy based on noninvasive biomarkers provides promising opportunities for early diagnosis and dynamic treatment management. Recently, a growing number of studies have demonstrated the potential of cell-free RNA (cfRNA) as a new type of noninvasive biomarker in body fluids, such as blood, saliva, and urine. Meanwhile, transcriptomes based on high-throughput RNA detection technologies keep discovering new cfRNA biomarkers. In this review, we introduce the origins and applications of cfRNA, describe its detection and qualification methods in liquid biopsy, and summarize a comprehensive list of cfRNA biomarkers in different GI cancer types. Moreover, we also discuss perspective studies of cfRNA to overcome its current limitations in clinical applications. This article is categorized under: RNA in Disease and Development > RNA in Disease.

Diagnostic value of circulating microRNAs for esophageal cancer: a meta-analysis based on Asian data

BACKGROUND AND OBJECTIVE

esophageal cancer (EC) is one of the most common gastrointestinal malignant diseases. We conducted a comprehensive meta-analysis to explore the clinical applicability of circulating microRNA for the diagnosis of EC.

METHODS

as of September 10, 2021, a comprehensive literature search was conducted on PubMed, Embase, Web of Science, Cochrane Library, Wanfang Database, and China National Knowledge Infrastructure (CNKI) to identify eligible studies. The sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the curve (AUC) were pooled to evaluate the test performance. The potential sources of heterogeneity were analyzed by subgroup analysis. Deeks' funnel plot was used to assess publication bias.

RESULTS

85 studies from 50 articles were included in the current meta-analysis. The overall pooled sensitivity was 0.82 (95 % CI, 0.79-0.84), specificity was 0.84 (95 % CI, 0.81-0.86), PLR was 4.9 (95 % CI, 4.2-5.9), NLR was 0.22 (95 % CI, 0.19-0.25), DOR was 22 (95 % CI, 17-29) and AUC was 0.89 (95 % CI, 0.86-0.92), respectively. Subgroup analysis suggested that miRNA clusters with a large sample size showed better diagnostic accuracy. Publication bias was not found.

CONCLUSIONS

circulating miRNAs can be used as a potential non-invasive biomarker for the diagnosis of EC in Asian populations.

The interplay of signaling pathways and miRNAs in the pathogenesis and targeted therapy of esophageal cancer

Globally, esophageal cancer (EC) is the 6th leading cause of cancer-related deaths and the second deadliest gastrointestinal cancer. Multiple genetic and epigenetic factors, such as microRNAs (miRNAs), influence its onset and progression. miRNAs are short nucleic acid molecules that can regulate multiple cellular processes by regulating gene expression. Therefore, EC initiation, progression, apoptosis evasions, invasion capacity, promotion, angiogenesis, and epithelial-mesenchymal transition (EMT) enhancement are associated with miRNA expression dysregulation. Wnt/-catenin signaling, Mammalian target of rapamycin (mTOR)/P-gp, phosphoinositide-3-kinase (PI3K)/AKT/c-Myc, epidermal growth factor receptor (EGFR), and transforming growth factor (TGF)-β signaling are crucial pathways in EC that are controlled by miRNAs. This review was conducted to provide an up-to-date assessment of the role of microRNAs in EC pathogenesis and their modulatory effects on responses to various EC treatment modalities.

MicroRNAs in esophageal squamous cell carcinoma: Application in prognosis, diagnosis, and drug delivery

MicroRNAs (miRNAs) play a vital role in various cell biology processes, including cancer formation. These small non-coding RNAs could function as diagnostic and prognostic markers. They may involve esophageal squamous cell carcinoma (ESCC) and distinctive miRNA expression profiles; they are also known as therapeutic targets in human diseases. Therefore, in this study, the function of miRNAs was reviewed regarding the prognosis and diagnosis of ESCC. The changes in miRNAs before and after cancer therapy and the effects of miRNAs on chemo-susceptibility patterns were also investigated. MiRNA delivery systems in ESCC were also highlighted, providing a perspective on how these systems can improve miRNA efficiency.

Circulating microRNA profile in humans and mice with congenital GH deficiency

Reduced inflammation, increased insulin sensitivity, and protection against cancer are shared between humans and mice with GH/IGF1 deficiency. Beyond hormone levels, miRNAs are important regulators of metabolic changes associated with healthy aging. We hypothesized that GH deficiency in humans alters the abundance of circulating miRNAs and that a subset of those miRNAs may overlap with those found in GH-deficient mice. In this study, subjects with untreated congenital isolated GH deficiency (IGHD; n = 23) and control subjects matched by age and sex (n = 23) were recruited and serum was collected for miRNA sequencing. Serum miRNAs from young (6 month) and old (22 month) Ames dwarf (df/df) mice with GH deficiency and their WT littermates (n = 5/age/genotype group) were used for comparison. We observed 14 miRNAs regulated with a genotype by age effect and 19 miRNAs regulated with a genotype effect independent of age in serum of IGHD subjects. These regulated miRNAs are known for targeting pathways associated with longevity such as mTOR, insulin signaling, and FoxO. The aging function was overrepresented in IGHD individuals, mediated by hsa-miR-31, hsa-miR-146b, hsa-miR-30e, hsa-miR-100, hsa-miR-181b-2, hsa-miR-195, and hsa-miR-181b-1, which target the FoxO and mTOR pathways. Intriguingly, miR-181b-5p, miR-361-3p, miR-144-3p, and miR-155-5p were commonly regulated in the serum of humans and GH-deficient mice. In vitro assays confirmed target genes for the main up-regulated miRNAs, suggesting miRNAs regulated in IGHD individuals can regulate the expression of age-related genes. These findings indicate that systemic miRNAs regulated in IGHD individuals target pathways involved in aging in both humans and mice.

The Diagnostic and Prognostic Value of a Liquid Biopsy for Esophageal Cancer: A Systematic Review and Meta-Analysis

Simple Summary

The “liquid biopsy” is a novel concept for detecting circulating biomarkers in the peripheral blood of patients with various cancers, including esophageal cancer. There are two main methods to identify circulating cancer related biomarkers such as morphological techniques or molecular biological techniques. There are some differences in the sensitivity and specificity for detecting circulating tumor cells (CTCs) or circulating markers between each method. Although it is still challenging to determine strong candidates for early diagnosis and predicting prognosis in patients with esophageal cancer, our meta-analysis might be a milestone for the future development of liquid biopsies in use with esophageal cancer.

Abstract

Esophageal cancer is among the most aggressive diseases, and circulating tumor cells (CTCs) have been recognized as novel biomarkers for various cancers over the past two decades, including esophageal cancer. CTCs might provide crucial clinical information for predicting cancer prognosis, monitoring therapeutic responses or recurrences, or elucidating the mechanism of metastasis. The isolation of CTCs is among the applications of a “liquid biopsy”. There are various technologies for liquid biopsies, and they are classified into two main methods: cytometric or non-cytometric techniques. Here, we review a total of 57 eligible articles to summarize various technologies for the use of a liquid biopsy in esophageal cancer and perform a meta-analysis to assess the clinical utility of liquid biopsies as a prognostic and diagnostic biomarker technique. For prognostic evaluation, the pooled hazard ratio in the cytometric assay is relatively higher than that of the non-cytometric assay. On the other hand, a combination of multiple molecules, using a non-cytometric assay, might be a favorable biomarker technique for the early diagnosis of esophageal cancer. Although determining strong evidence for a biomarker by using a liquid biopsy is still challenging, our meta-analysis might be a milestone for the future development of liquid biopsies in use with esophageal cancer.

Diagnostic and prognostic value of serum miRNA-1290 in human esophageal squamous cell carcinoma

BACKGROUND

It is well known that some circulating microRNAs (miRNAs) are highly stable and might serve as promising biomarkers for many types of human cancer including esophageal squamous cell carcinoma (ESCC). However, the potential clinical significance of serum miR-1290 in ESCC remained unknown.

OBJECTIVE

The aim of this study was to investigate the diagnostic and prognostic value of serum miR-1290 for ESCC.

METHODS

The expression levels of serum miRNA-1290 in patients with ESCC and healthy controls were detected, and their potential diagnostic and prognostic value was analyzed.

RESULTS

Our results showed that tissue and serum miR-1290 levels were both significantly elevated in ESCC compared to their respective controls. Tissue miR-1290 levels were highly correlated with serum miR-1290 levels. High serum miR-1290 levels were significantly associated with worse clinicopathological characteristics. Patients with high serum miR-1290 levels had significantly worse survival. Further multivariate analysis showed that serum miR-1290 was an independent risk factor for ESCC. Serum miR-1290 could effectively discriminate ESCC cases from normal controls.

CONCLUSIONS

The level of serum microRNA-1290 in ESCC patients increased significantly, and its expression level could reflect the progress of ESCC, suggesting that serum microRNA-1290 might be a useful diagnostic and prognostic marker of ESCC.

Prognostic Value of MicroRNA-15a in Human Cancers: A Meta-Analysis and Bioinformatics

Background

Although several studies have proved the relationship between the prognostic value of miRNA-15a and different types of cancer, the result remains controversial. Thus, a meta-analysis was conducted to clarify the prognostic value of miRNA-15a expression level in human cancers.

Methods

We enrolled appropriate literature by searching the databases of PubMed, Embase, and Web of Science. Subsequently, we extracted HRs and their 95% CIs and calculated pooled results of miRNA-15a for overall survival (OS) and disease-free survival (DFS). Besides, subgroup analysis, sensitivity analysis, and publication bias were also revealed in this study. We also further validated this meta-analysis using the Kaplan-Meier plotter database.

Result

10 studies, including 1616 patients, were embraced in our meta-analysis. The result showed the lower expression of miRNA-15a significantly predicted adverse OS (HR=2.17, 95% CI: 1.41-3.34), but there is no significant association between the expressing level and DFS in cancer patient (HR=2.04, 95% CI: 0.60-6.88). Based on Kaplan-Meier plotter database, we found the same results in bladder Carcinoma, head-neck squamous cell carcinoma, liver hepatocellular carcinoma, lung squamous cell carcinoma, pancreatic ductal adenocarcinoma, rectum adenocarcinoma, stomach adenocarcinoma, and uterine corpus endometrial carcinoma, but opposite results were found in cervical squamous cell carcinoma and esophageal carcinoma.

Conclusion

Low expressing levels of miRNA-15a indicated poor OS, while miRNA-15a can be used as a prediction biomarker in different cancer types.

Liquid Biopsy beyond Circulating Tumor Cells and Cell-Free DNA

Liquid biopsy represents the analysis of tumor-derived material in the blood and other body fluids of cancer patients. This portrays a minimally invasive detection tool for molecular biomarkers. Liquid biopsy has emerged as a complementary or alternative method to surgical biopsy. This non-invasive detection tool overcomes the recurrent problems in the clinical assessment of tumors that stem from the lack of accessibility to the tumor tissue and its clonal heterogeneity. Moreover, body fluid-derived components have shown to reflect the genetic profile of both primary and metastatic lesions and provide a real-time monitoring of tumor dynamics, representing a great promise for personalized medicine. This review will highlight the latest breakthroughs and the current applications of several tumor-derived biomarkers that can be found in body fluids. The authors will focus on tumor-derived exosomes, tumor-educated platelets, and circulating tumor miRNAs and mRNAs, and how these can be used for tumor detection.

The expression levels of miRNA-15a and miRNA-16-1 in circulating tumor cells of patients with diffuse large B-cell lymphoma

MicroRNAs (miRNAs) have major roles in nearly all cellular process including gene expression, and may behave as oncogene or tumor suppressor gene by binding to complementary sequences in the target mRNA. The circulating microRNA-15a (miRNA-15a) and microRNA-16-1 (miRNA-16-1) of 15 healthy adults and of 40 untreated patients diagnosed with diffuse large B-cell lymphoma (DLBC) were recruited to investigate the expression levels. The expression levels of miRNA-15a, and miRNA-16-1 genes of the untreated DLBCL patients, and healthy individuals with matched age, sex and ethnicity were examined. MicroRNA expression profiles obtained from peripheral blood were investigated. The samples were collected from 40 patients diagnosed with DLBC patients, and from 15 healthy controls. Two miRNAs were selected, and expression profile was examined using a quantitative real-time polymerase chain reaction (qPCR) based on the previous studies. Statistically significant expression level differences (p < 0.05) were detected for miRNA-16-1 in DLBCL patients and healthy control groups. miRNA-16-1 gene expression level was found approximately ninefold higher in the patient group compared to the controls; however, no statistical difference was detected in the expression profile of miRNA-15a between the both groups. On the other hand, the decreased gene expression in miRNA16-1 was observed in 88.3% of DLBCL patients. These results suggested that there was no statistically significant decrease in the miRNA-15a gene expression in DLBCL patients (p > 0.05). On the contrary to the literature, miRNA-16-1 expression level was suppressed in DLBCL group in our study, however no whole gene silencing was performed. MicroRNA-16-1 might be suggested to behave as a tumor suppressor in DLBCL in our study.

Prognostic Value of MicroRNAs in Esophageal Carcinoma: A Meta-Analysis

Background

Numerous articles have reported that abnormal expression levels of microRNAs (miRNAs) are related to the survival times of esophageal carcinoma (EC) patients, which contains esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (ESCC). Nevertheless, there has not been a comprehensive meta-analysis to assess the accurate prognostic value of miRNAs in EC.

Methods

Studies published in English up to April 12, 2018 that evaluated the correlation of the expression levels of miRNAs with overall survival (OS) in EC were identified by online searches in PubMed, EMBASE, Web of Science, and the Cochrane Database of Systematic Reviews performed by two independent authors. The pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were used to estimate the correlation between OS and miRNA expression. HR ≥ 2 was considered cutoff for considering the miRNA as prognostic candidate.

Results

Forty-four pertinent articles with 22 miRNAs and 4310 EC patients were ultimately included. EC patients with tissue expression levels of high miR-21 or low miR-133a (HR = 2.48, 95% CI = 1.50–4.12), miR-133b (HR = 2.15, 95% CI = 1.27–3.62), miR-138 (HR = 2.27, 95% CI = 1.68–3.08), miR-203 (HR = 2.83, 95% CI = 1.35–5.95), miR-375 and miR-655 (HR = 2.66, 95% CI = 1.16–6.12) had significantly poorer OS (P < 0.05). In addition, EC patients with blood expression levels of high miR-21 (HR = 2.19, 95% CI = 1.31–3.68) and miR-223 had significantly shorter OS (P < 0.05).

Conclusions

In conclusion, tissue expression levels of miR-21, miR-133a, miR-133b, miR-138, miR-203, miR-375, and miR-655 and blood expression levels of miR-21 and miR-223 demonstrate significant prognostic value. Among them, the expression levels of miR-133a, miR-133b, miR-138, miR-203, and miR-655 in tissue and the expression level of miR-21 in blood are potential prognostic candidates for predicting OS in EC.

Down-regulated serum miR-126 is associated with aggressive progression and poor prognosis of gastric cancer

BACKGROUND

miR-126 functions as a tumor suppressor in gastric cancer (GC), however, the clinical significance of serum miR-126 in GC remains unclear.

OBJECTIVE

To investigate the associations of serum miR-126 level with the clinicopathological characteristics and prognosis of GC patients.

METHODS

Quantitative real-time polymerase chain reaction was performed to examine the expression levels of miR-126 in 338 GC patients' tissues and sera, and 50 healthy controls' sera. The associations of serum miR-126 with clinicopathological characteristics and clinical outcome were evaluated.

RESULTS

Compared with the matched adjacent non-tumor tissues and normal sera, miR-126 expression was significantly down-regulated in both tumor tissues and sera of GC patients. Importantly, there was a positive correlation between tissue and serum levels of miR-126 in GC patients. A reduced serum miR-126 level statistically correlated with aggressive clinicopathological characteristics, such as larger tumor size, deeper local invasion, more lymph node metastasis, advanced TNM stage, and poorer prognosis. Notably, multivariate analysis identified reduced serum miR-126 level as an independent predictor for the unfavorable prognosis of GC.

CONCLUSIONS

These results indicate for the first time that serum miR-126 may serve as a novel prognostic biomarker in GC.

The miR-15a/16 gene cluster in human cancer: A systematic review

MicroRNAs (miRNAs) are an important class of endogenous small noncoding single-stranded RNAs that suppress the expression of their target genes through messenger RNA (mRNA) degradation to inhibit transcription and translation. MiRNAs play a crucial regulatory role in many biological processes including proliferation, metabolism, and cellular malignancy. miR-15a/16 is an important tumor suppressor gene cluster with a variety of factors that regulate its transcriptional activity. It has been discovered that a relative reduction of miR-15a/16 expression in various cancers is closely related to the occurrence and progression of tumors. miR-15a/16 takes part in a wide array of biological processes including tumor cell proliferation, apoptosis, invasion, and chemoresistance by binding to the 3'-untranslated region of its target gene's mRNA. In this review, we will examine the complex regulatory network of miR-15a/16 gene expression and its biological functions in human cancers to further elucidate the molecular mechanisms of its antitumor effects.

Circulating serum oncologic miRNA in pediatric juvenile pilocytic astrocytoma patients predicts mural nodule volume

BACKGROUND

Juvenile pilocytic astrocytomas represent the largest group of pediatric brain tumors. The ideal management for these tumors is early, total surgical resection. To detect and track treatment response, a screening tool is needed to identify patients for surgical evaluation and assess the quality of treatment. The identification of aberrant miRNA profiles in the sera of juvenile pilocytic astrocytoma patients could provide such a screening tool.

METHODS

The authors reviewed the serum profiles of 84 oncologically relevant miRNAs in pediatric juvenile pilocytic astrocytoma patients via qPCR screening.

RESULTS

miR-21, miR-15b, miR-23a, and miR-146b were significantly elevated in the sera of JPA patients as compared to non-oncologic controls, oncologic controls, and post-JPA resection samples (p < 0.001, 0.022, 0.034, 0.044). miR-21 had the highest AUC on ROC analysis (AUC > 0.99, sensitivity 75%, specificity 100%). All four miRNAs also correlated well with tumor mural nodule size, though they only poorly correlated with total tumor size, including cystic components (Spearman's R²: miR-21 91.7 vs 6.9%, miR-15b 86.3 vs 23.1%, miR-23a 85.8 vs 23.0%, miR-146b 59.8 vs 11.9%).

CONCLUSION

In this small pilot study, pediatric juvenile pilocytic astrocytoma patients had significant elevations in serum miR-21, miR-15b, miR-23a, and miR-146b levels that do not appear to be driven by hydrocephalus or local distortion of the intracranial contents. These alterations correlate with solid tumor component volume and reverse with complete tumor resection, suggesting that this serum miRNA profile may delineate biomarkers for screening and tracking juvenile pilocytic astrocytoma patients. Additional studies, with a larger cohort, are needed to verify these results.

Diagnostic and Prognostic Value of Circulating MicroRNAs for Esophageal Squamous Cell Carcinoma: a Systematic Review and Meta-analysis

Background and Aim: MicroRNAs, dysregulated in the circulation of esophageal squamous cell carcinoma (ESCC) patient, have been assumed to be with great potential in the diagnosis and prognosis of esophageal cancer. We aimed to review previous articles on ESCC. Methods: A search of electronic databases was performed before Nov 12, 2017. We summarized the identification of microRNA imbalance in the blood of ESCC compared with the healthy controls, with the objective to evaluate the efficiency of microRNAs in diagnosing and forecasting ESCC. Results: A total of 35 studies investigating plasma or serum microRNAs were included in the meta-analysis. Based on the consequences of the quality assessment of each study, the articles involved were appropriate for quantitative synthesis. For diagnostic meta-analysis. The overall pooled sensitivity, specificity, and area under the curve of circulating microRNA is 0.794 (95% CI: 0.765 - 0.820), 0.779 (95%CI: 0.746 - 0.808), 0.86 (95%CI: 0.82 - 0.88). The diagnostic value of each microRNA was calculated respectively. For prognostic meta-analysis, the overall pooled hazard ratios of higher microRNA expression in circulation was 1.34 (95% CI: 1.14-1.58), which could significantly predict poorer survival in ESCC. Conclusions: Circulating microRNAs distinguish patients with ESCC from healthy controls with high sensitivity and specificity, compared to other invasive currently used screening methods. Simultaneously, there was prognostic value for the prognosis of ESCC.

Diagnostic and prognostic value of serum miR-15a and miR-16-1 expression among egyptian patients with prostate cancer

Prostate cancer (PCa) is considered the most common malignancy in men. The aim of this study is to assess the role of serum miR-15a and miR-16-1 expression in PCa development, diagnosis and prognosis aiming to find a specific noninvasive biomarker. This study comprised 70 patients with PCa, 70 patients complaining of benign prostatic hyperplasia (BPH), 30 patients with chronic prostatitis and 70 controls. Circulating miR-15a and miR-16-1 expression was detected by real-time polymerase chain reaction. Prostate specific antigen levels were measured by enzyme-linked immunosorbent assay. The expression levels of serum miR-15a were decreased in PCa patients compared with controls, chronic prostatitis and BPH patients (0.43 ± 0.12, 1.7 ± 0.76, 1.56 ± 0.34 and 1.53 ± 0.65, respectively). The expression levels of serum miR-16-1 were decreased in PCa patients compared with controls, chronic prostatitis and BPH patients (0.55 ± 0.23, 2.15 ± 0.87, 2.08 ± 0.54 and 1.96 ±0.61, respectively). Downregulation of miR-15a and miR-16-1 correlated with higher Gleason score (P = 0.002 and P = 0.006, respectively), higher tumor stage (P = 0.001 and P = 0.01, respectively), PCa metastasis (P = 0.002 and P = 0.025, respectively) and lymph node involvement (P = 0.02 and P = 0.007, respectively). Moreover, Receiver operating characteristic curve analysis revealed that combined miR-15a/miR-16-1 and PSA increased the sensitivity and specificity for the diagnosis of PCa (97.1% and 94.3%, respectively) more than prostate specific antigen alone (82.9% sensitivity and 75.7% specificity). Combined serum miR-15a/miR-16-1 expression and PSA level can be used as promising specific noninvasive biomarkers in the diagnosis and prognosis of PCa better than prostate specific antigen alone. © 2018 IUBMB Life, 70(5):437-444, 2018.

MACC1 induces autophagy to regulate proliferation, apoptosis, migration and invasion of squamous cell carcinoma

Metastasis-associated colon cancer-1 (MACC1) plays an important role in cancer development, but the role and mechansim of MACC1 in squamous cell carcinoma (ESCC) remain unclear. In this study, we found that MACC1 expression was increased in ESCC, and correlated with lymph node metastasis. MACC1 knockdown suppresed ESCC cell proliferation, metastasis and enchanced cell apoptosis. Moreover, MACC1 knockdown inhibited ESCC cell autophagy, and 3-methyladenine was able to rescue MACC1-induced malignant phenotype of ESCC cells. Furthermore, MACC1 knockdown inactivated AMPK-ULK1 signaling pathway, and metformin could rescue MACC1-induced autophagy in ESCC cells. Collectively, this study found that upregulation of MACC1 in ESCC was associated with lymph node metastasis of patients, and MACC1 regulated ESCC cell proliferation, apoptosis, migration and invasion mainly through AMPK-ULK1 induced autophagy.

MicroRNA-381 enhances radiosensitivity in esophageal squamous cell carcinoma by targeting X-linked inhibitor of apoptosis protein

Background

Increasing evidence indicates that radioresistance remains a major problem in the treatment of patients with esophageal squamous cell carcinoma (ESCC). This study was designed to investigate the expression of microRNA-381 (miR-381) and its function in the radioresistance of ESCC.

Methods

In this study, miR-381 expression was first detected in ESCC cell lines and tissue samples by quantitative real-time polymerase chain reaction (qRT-PCR). Then, the effects of miR-381 expression on growth, apoptosis, and radiosensitivity of ESCC cells were analyzed by MTT, colony formation, and flow cytometry, respectively. Dual-luciferase reporter assays were performed to validate the regulation of a putative target of miR-381, in corroboration with qRT-PCR and Western blotting assays.

Results

ESCC cell lines or tissues were found to express significantly lower miR-381 than normal esophageal epithelial cells or adjacent normal tissues, respectively. Ectopic expression of miR-381 in ESCC cell lines blocked proliferation, reduced colony formation, enhanced apoptosis, and increased radiosensitivity by enhancing irradiation-induced apoptosis. In addition, dual-luciferase reporter assays showed that miR-381 binds to the 3′-untranslated region of X-linked inhibitor of apoptosis protein (XIAP), suggesting that XIAP should be a direct target of miR-381. Re-expression of miR-381 suppressed XIAP protein expression in ESCC cells, and the effects of miR-381 upregulation on ESCC cells were found to be similar with silencing of XIAP. In addition, XIAP mRNA expression significantly increased in ESCC tissues and was inversely correlated with miR-381 expression.

Conclusion

The results of this study suggest that miR-381/XIAP pathway contributed to the growth inhibition, increase in apoptosis, and enhancement of radiosensitivity in ESCC cells Therefore, miR-381 may be a potential therapeutic target in human ESCC.