Downregulated miR-486-5p acts as a tumor suppressor in esophageal squamous cell carcinoma

MicroRNAs: A novel signature in the metastasis of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a malignant epithelial tumor, characterized by squamous cell differentiation, it is the sixth leading cause of cancer-related deaths globally. The increased mortality rate of ESCC patients is predominantly due to the advanced stage of the disease when discovered, coupled with higher risk of metastasis, which is an exceedingly malignant characteristic of cancer, frequently leading to a high mortality rate. Unfortunately, there is currently no specific and effective marker to predict and treat metastasis in ESCC. MicroRNAs (miRNAs) are a class of small non-coding RNA molecules, approximately 22 nucleotides in length. miRNAs are vital in modulating gene expression and serve pivotal regulatory roles in the occurrence, progression, and prognosis of cancer. Here, we have examined the literature to highlight the intimate correlations between miRNAs and ESCC metastasis, and show that ESCC metastasis is predominantly regulated or regulated by genetic and epigenetic factors. This review proposes a potential role for miRNAs as diagnostic and therapeutic biomarkers for metastasis in ESCC metastasis, with the ultimate aim of reducing the mortality rate among patients with ESCC.

Circulating miRNA as a Biomarker in Oral Cancer Liquid Biopsy

Oral cancer is currently challenging the healthcare system, with a high incidence among the population and a poor survival rate. One of the main focuses related to this malignancy is the urge to implement a viable approach for improving its early diagnosis. By introducing the use of liquid biopsy and the identification of potential biomarkers, aiming for a noninvasive approach, new advancements offer promising perspectives in the diagnosis of oral cancer. The present review discusses the potential of circulating miRNAs as oral cancer biomarkers identified in body fluids such as serum, plasma, and saliva samples of oral cancer patients. Existing results reveal an important implication of different miRNA expressions involved in the initiation, development, progression, and metastasis rate of oral malignancy. Liquid biomarkers can play a crucial role in the development of the concept of personalized medicine, providing a wide range of clinical applications and future targeted therapies.

MiR-486-5p specifically suppresses SAPCD2 expression, which attenuates the aggressive phenotypes of lung adenocarcinoma cells

BACKGROUND

MiR-486-5p expression is restrained in lung adenocarcinoma (LUAD). However, much less has been understood on its role in LUAD. We aimed to explore the biofunctions of miR-486-5p in LUAD.

METHODS

A differential expression analysis based on The Cancer Genome Atlas-LUAD dataset was done to screen the differently expressed miRNAs and mRNAs. MiR-486-5p and SAPCD2 mRNA expression was analyzed by qRT-PCR, and protein level of SAPCD2 was assayed by western blot. Upregulation and downregulation of miR-486-5p or SAPCD2 were achieved by cell transfection. For cell function assays, the proliferation of cancer cells was examined by MTT assay. Cell apoptosis was assessed by flow cytometry and microscopy. Transwell assay was applied to evaluate cell migration and invasion. A dual-luciferase detection was employed to determine the miRNA-mRNA targeting relationship.

RESULTS

MiR-486-5p expression was notably reduced in LUAD tissue and cell lines. Upregulating miR-486-5p restrained the anti-apoptotic and proliferative abilities, as well as cell migratory and invasive phenotypes in LUAD cells. SAPCD2 was determined as one target of miR-486-5p. Also, SAPCD2 forced expression was able to attenuate the inhibitory impacts of miR-486-5p on the malignant phenotypes of LUAD cells.

CONCLUSION

MiR-486-5p suppressed cell malignant progression in LUAD by targeting SAPCD2, suggesting that the two may be targets for LUAD treatment.

Combined miR-486 and GP88 (Progranulin) Serum Levels Are Suggested as Supportive Biomarkers for Therapy Decision in Elderly Prostate Cancer Patients

Our study aimed to assess the applicability of miR-486 in combination with soluble GP88 protein as a diagnostic and/or predictive biomarker for prostate cancer (PCa) patients. miR-486 and GP88 levels in serum samples from 136 patients undergoing MRI-guided biopsy of the prostate were assessed by qRT−PCR and ELISA, respectively. Of these, 86 patients received a histologically confirmed diagnosis of PCa. Neither marker showed an association with the diagnosis of cancer. PCa patients were separated based on (i) treatment into patients with active surveillance or patients with any type of curative treatment and (ii) age into elderly (>68 years) patients and younger patients (≤68 years). In elderly patients (N = 41) with the intention of curative treatment at optimized cut-off values, significantly higher GP88 levels (p = 0.018) and lower miR-486 levels (p = 0.014) were observed. The total PSA level and ISUP biopsy grade were used in a baseline model for predicting definitive therapy. The baseline model exhibited an area under the curve (AUC) of 0.783 (p = 0.005). The addition of the serum biomarkers miR-486 and GP88 to the baseline model yielded an improved model with an AUC of 0.808 (p = 0.002). Altogether, combined miR-486 and GP88 serum levels are associated with and are therefore suggested as supportive biomarkers for therapy decisions, particularly in elderly PCa patients.

miR-486-5p Serves as a Diagnostic Biomarker for Sepsis and Its Predictive Value for Clinical Outcomes

Background

As a molecular detection method, miRNA can quickly diagnose and prevent diseases, intervene in disease as early as possible, and reduce mortality. This study was to investigate the potential clinical diagnostic and predictive significance of miR-486-5p in sepsis and its correlation with inflammation and disease severity.

Methods

The serum miR-486-5p in 108 sepsis, 60 pneumonia-infected, and 101 healthy controls were detected by RT-qPCR. Spearman coefficient detects the correlation between serum miRNA and disease severity indicators (APACHE II, SOFA scores), and inflammation indicators (CRP, PCT), respectively. The diagnostic significance of miR-486-5p in sepsis was analyzed by the ROC curve. Kaplan–Meier estimator and Cox regression hazards analysis of the predictive significance of serum miR-486-5p in 28-day survival from sepsis.

Results

Serum miR-486-5p was increased in sepsis patients compared with healthy control and pneumonia-infected patients (P < 0.001). And increased serum miR-486-5p was positively associated with disease severity (SOFA score and APACHE II score) and inflammation (CRP and PCT). Serum miR-486-5p can not only identify sepsis patients from healthy controls (AUC = 0.914) but also significantly distinguish sepsis patients from pneumonia-infected patients (AUC = 0.814), showing good potential as a diagnostic biomarker for sepsis. In addition, serum miR-486-5p was an independent predictor of 28-day survival (log-rank P = 0.012), and patients with high levels of miR-486-5p had a poorer overall 28-day survival (HR = 3.057, 95% CI = 1.385–17.817, P = 0.014).

Conclusion

miR-486-5p is a potential diagnostic biomarker for sepsis, and its high level is significantly correlated with the disease severity and inflammation. In addition, miR-486-5p were predictive risk factors for 28-day survival in sepsis patients.

Overexpression of microRNA‑486 affects the proliferation and chemosensitivity of mesothelioma cell lines by targeting PIM1

Dysregulated levels of microRNAs (miRNAs or miRs), involved in oncogenic pathways, have been proposed to contribute to the aggressiveness of malignant pleural mesothelioma (MPM). Previous studies have highlighted the downregulation of miRNA miR-486-5p in patients with mesothelioma and the introduction of miRNA mimics to restore their reduced or absent functionality in cancer cells is considered an important therapeutic strategy. The aim of the present study was to evaluate the mechanisms through which miRNAs may influence the functions, proliferation and sensitivity to cisplatin of MPM cells. In the present study, a miR-486-5p mimic was transfected into the H2052 and H28 MPM cell lines, and cell viability, proliferation, apoptosis and mitochondrial membrane potential were monitored. miR-486-5p overexpression led to a clear impairment of cell proliferation, targeting CDK4 and attenuating cell cycle progression. In addition, transfection with miR-486-5p mimic negatively regulated the release of inflammatory factors and the expression of Provirus integration site for Moloney murine leukaemia virus 1 (PIM1). The sensitivity of the cells to cisplatin was enhanced by enhancing the apoptotic effects of the drug and impairing mitochondrial function. On the whole, the present study demonstrates that miR-486-5p may play an important role in MPM treatment by targeting multiple pathways involved in tumour development and progression. These activities may be mostly related to the downregulation of PIM1, a crucial regulator of cell survival and proliferation. Furthermore, these results provide support for the combined use of miR-486-5p with chemotherapy as a therapeutic strategy for MPM.

Prognostic value of microRNA-378 in esophageal cancer and its regulatory effect on tumor progression

The incidence and mortality rates of esophageal squamous cell carcinoma (ESCC) are high in China, which has increased the clinical and economic burden. The present study aimed to investigate the role of microRNA (miRNA/miR)-378 in ESCC. Reverse transcription-quantitative polymerase chain reaction analysis was performed to detect miR-378 expression in ESCC tissues and cell lines. Survival analysis was performed using the Kaplan-Meier method, while Cox regression analysis was performed to determine the prognostic value of miR-378 in ESCC. miR-378 mimic and miR-378 inhibitor was transfected into ESCC cells to overexpress or knockdown miR-378 expression levels in ESCC cells. The Cell Counting Kit-8 assay was performed to assess the proliferative ability of ESCC cells, while the Transwell assay was conducted to assess the effect of miR-378 on the migratory and invasive abilities of ESCC cells. The results demonstrated that miR-378 displayed significantly lower expression both in ESCC cells and tissues by comparison with those in normal cells and adjacent tissues. In addition, patients with low miR-378 expression had a worse prognosis and a shorter overall survival time than those with high miR-378 expression. Furthermore, low miR-378 expression promoted ESCC cell proliferation, migration and invasion. Taken together, the results of the present study suggest that miR-378 may act as a tumor suppressor in the occurrence and development of ESCC.

Transcriptomic and microRNA Expression Profiles Identify Biomarkers for Predicting Neo-Chemoradiotherapy Response in Esophageal Squamous Cell Carcinomas (ESCC)

Neo-chemoradiotherapy (nCRT) before surgery is a standard treatment for locally advanced esophageal cancers. However, the treatment outcome of nCRT varied with different patients. This study aimed to identify potential biomarkers for prediction of nCRT-response in patients with esophageal squamous cell carcinoma (ESCC). Microarray datasets of nCRT responder and non-responder samples (access number GSE45670 and GSE59974) of patients with ESCC were downloaded from Gene Expression Omnibus (GEO) database. The mRNA expression profiles of cancer biopsies from four ESCC patients were analyzed before and after nCRT. Differentially expressed genes (DEGs) and miRNAs were screened between nCRT responder and non-responder ESCC samples. Functional enrichment analysis was conducted for these DEGs followed by construction of protein-protein interaction (PPI) network and miRNA-mRNA regulatory network. Finally, univariate survival analysis was performed to identify candidate biomarkers with prognostic values in ESCC. We identified numerous DEGs and differentially expressed miRNAs from nCRT responder group. GO and KEGG analysis showed that the dysregulated genes were mainly involved in biological processes and pathways, including "response to stimulus", "cellular response to organic substance", "regulation of signal transduction", "AGE-RAGE signaling pathway in diabetic complications", and "steroid hormone biosynthesis". After integration of PPI network and miRNA-mRNA network analysis, we found eight genes, TNF, AKR1C1, AKR1C2, ICAM1, GPR68, GNB4, SERPINE1 and MMP12, could be candidate genes associated with disease progression. Univariate cox regression analysis showed that there was no significant correlation between dysregulated miRNAs (such as hsa-miR-34b-3p, hsa-miR-127-5p, hsa-miR-144-3p, and hsa-miR-486-5p, et al.) and overall survival of ESCC patients. Moreover, abnormal expression of MMP12 was significantly correlated with pathological degree, TNM stage, lymph nodes metastasis, and overall survival of ESCC patients (p < 0.05). Taken together, our study identified that MMP12 might be a useful tumor biomarker and therapeutic target for ESCC.

miR-486-5p: A Prognostic Biomarker for Chronic Myeloid Leukemia

MicroRNA miR-486-5p has been reported as a potential biomarker for diagnosis, prognosis, and as a therapeutic target in various cancers. In this study, we analyzed alterations in the expression of miR-486-5p in chronic Myeloid Leukemia (CML) patients. Initially, the expression of miR-486-5p was studied in the BCR-ABL1+ve CML K562 cell line by quantitative real-time polymerase chain reaction (qRT-PCR). The results indicated that the miR-486-5p expression was significantly upregulated in K562 cells after imatinib exposure, as compared to untreated K562 cells (p-value = 0.047). These observations were corroborated by a hospital-based study of the miR-486-5p expression in peripheral blood leucocytes of 36 CML patients in the chronic phase (CP) and compared with age and sex-matched healthy volunteers as control subjects. qRT-PCR-based quantification revealed significant downregulation of the miR-486-5p expression in newly diagnosed untreated CP-CML patients' samples (2^-ΔCt = 13.19 ± 14.41) as compared to control samples (2^-ΔCt = 254.5 ± 274.8) (p-value < 0.0001). Levels of miR-486-5p were found to be distinctly elevated in the post-imatinib treatment samples of CML patients (2^-ΔCt = 469.7 ± 312.9) as compared to pre-treatment samples (p-value < 0.0001). CML patients' clinical and hematological responses to imatinib therapy (oral dose of 400 mg OD) were monitored for 12 months. The correlation of pre-treatment miR-486-5p levels with Sokal score indicated that patients with a higher expression of miR-486-5p had better prognoses. Patients with higher pre-imatinib miR-486-5p levels also showed a major hematologic response to imatinib in a shorter time and vice versa. To the best of our knowledge, this is the first report of alterations in the miR-486-5p expression in peripheral blood leucocytes of CML patients. Our observations support a tumor suppressor role of miR-486-5p in CML. The downregulation of the miR-486-5p expression may be critically important in the disease progression of CML patients. The upregulation of the miR-486-5p expression in post-imatinib exposure K562 cells and CML patients after 12 months of imatinib treatment suggests an onco-suppressor effector role of miR-486-5p in the BCR-ABL downstream signaling pathway. miR-486-5p can be explored as a novel biomarker for the early detection of CML.

Identification of four genes and biological characteristics of esophageal squamous cell carcinoma by integrated bioinformatics analysis

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) has become one of the most serious diseases affecting populations worldwide and is the primary subtype of esophageal cancer (EC). However, the molecular mechanisms governing the development of ESCC have not been fully elucidated.

METHODS

The robust rank aggregation method was performed to identify the differentially expressed genes (DEGs) in six datasets (GSE17351, GSE20347, GSE23400, GSE26886, GSE38129 and GSE77861) from the Gene Expression Omnibus (GEO). The Search Tool for the Retrieval of Interacting Genes (STRING) database was utilized to extract four hub genes from the protein-protein interaction (PPI) network. Module analysis and disease free survival analysis of the four hub genes were performed by Cytoscape and GEPIA. The expression of hub genes was analyzed by GEPIA and the Oncomine database and verified by real-time quantitative PCR (qRT-PCR).

RESULTS

In total, 720 DEGs were identified in the present study; these genes consisted of 302 upregulated genes and 418 downregulated genes that were significantly enriched in the cellular component of the extracellular matrix part followed by the biological process of the cell cycle phase and nuclear division. The primary enriched pathways were hsa04110:Cell cycle and hsa03030:DNA replication. Four hub genes were screened out, namely, SPP1, MMP12, COL10A1 and COL5A2. These hub genes all exhibited notably increased expression in ESCC samples compared with normal samples, and ESCC patients with upregulation of all four hub genes exhibited worse disease free survival.

CONCLUSIONS

SPP1, MMP12, COL10A1 and COL5A2 may participate in the tumorigenesis of ESCC and demonstrate the potential to serve as molecular biomarkers in the early diagnosis of ESCC. This study may help to elucidate the molecular mechanisms governing ESCC and facilitate the selection of targets for early treatment and diagnosis.

Long non-coding RNA SNHG6 increases JAK2 expression by targeting the miR-181 family to promote colorectal cancer cell proliferation

BACKGROUND

Long non-coding RNA (lncRNA) small nucleolar RNA host gene 6 (SNHG6) exerts a regulatory role in cancer biology, although its detailed functions and mechanisms in colorectal cancer (CRC) still remain unclear.

METHODS

A quantitative reverse transcriptase-polymerase chain reaction was implemented to investigate the expression of SNHG6, miR-181 family and Janus kinase 2 (JAK2) in CRC tissues and cell lines. The proliferation of CRC cells was detected by a cell counting kit-8 assay, and the apoptosis of CRC cells was determined by flow cytometry analysis. The interaction of the miR-181 family with SNHG6 or with the 3'-untranslated region of JAK2 was validated by the luciferase reporter gene method. The effects of SNHG6 and the miR-181 family on JAK2 expression were analyzed by western blotting.

RESULTS

SNHG6 was significantly up-regulated in CRC samples. The knockdown of SNHG6 reduced the proliferation of CRC cells and promoted the apoptosis, whereas the over-expression of SNHG6 had the opposite effect. SNHG6 could bind with all the four members of the miR-181 family, and expression in miR-181 family members was significantly down-regulated in CRC samples. SNHG6 expression was negatively correlated with the miR-181 family member expression in CRC samples. Moreover, over-expressed SNHG6 significantly counteracted the inhibitory effect of miR-181 mimics on CRC cell proliferation, as well as the promoting effect on apoptosis. Furthermore, SNHG6 over-expression and knockdown can promote and inhibit JAK2 expression, respectively, and miR-181 family member function is opposite to that of SNHG6 by repressing JAK2.

CONCLUSIONS

SNHG6 can exert a cancer-promoting effect in CRC by targeting miR-181 family members and up-regulating JAK2.

MicroRNA-105 plays an independent prognostic role in esophageal cancer and acts as an oncogene

BACKGROUND

Esophageal cancer is a common tumor with high mortality worldwide. In the present study, we aimed to investigate the prognostic significance and regulatory effects of miR-105 on cellular functions of esophageal cancer cells.

METHODS

The expression level of miR-105 was analyzed in esophageal cancer tissues and cell lines by qRT-PCR. Survival analysis was carried out using the Kaplan-Meier and the prognostic significance of miR-105 was analyzed with Cox regression analysis. The effects of miR-105 on cell proliferation, migration, and invasion abilities were detected with cellular experiments.

RESULTS

We found that miR-105 was significantly upregulated in esophageal cancer tissues and cell lines, compared with the control group, respectively. Moreover, overexpression of miR-105 was significantly associated with positive lymph node metastasis, advanced TNM stage, and poor overall survival. In addition, overexpression of miR-105 promoted cell proliferation, migration, and invasion in esophageal cancer cells, while downregulation of miR-105 suppressed these cellular behaviors.

CONCLUSION

Our findings indicate that a higher level of miR-105 predicts poorer prognosis in esophageal cancer patients, and miR-105 can promote esophageal cancer cell proliferation, migration, and invasion.

Downregulation of KIAA1199 by miR-486-5p suppresses tumorigenesis in lung cancer

Lung cancer is the primary cause of death among cancer patients in China, among which nonsmall cell lung cancer (NSCLC) makes up the great majority. Hence, it is imperative to identify the biomarkers and mechanisms involved in NSCLC oncogenesis. Our present research found that KIAA1199 expression was significantly increased in NSCLC and closely related to cell proliferation, motility, and poor prognosis. We demonstrated that knockdown of KIAA1199 reduced NSCLC cell growth and motility in vitro whereas overexpression of KIAA1199 had the opposite effect. Inhibition of KIAA1199 significantly suppressed tumor growth in mouse NSCLC xenograft models. Mechanistically, as an epidermal growth factor receptor (EGFR)‐binding protein, KIAA1199 promotes EGFR signaling and regulates EGFR‐dependent Src, Erk, and Akt phosphorylation, as well as downstream kinases in the EGF‐mediated EMT pathway. We demonstrated that KIAA1199 can function as a direct binding target for miR‐486‐5p and that miR‐486‐5p overexpression can attenuate proliferation and migration of NSCLC cells via regulating the EGFR signaling pathways. To conclude, our results defined KIAA1199 as an oncogenic protein that promotes cancer cell proliferation and migration by regulating EGF‐mediated signaling pathways. This study provided new insight into NSCLC oncogenesis, which could lead to the development of innovative therapeutic plans for NSCLC.

MiR-486-5p Act as a Biomarker in Endometrial Carcinoma: Promotes Cell Proliferation, Migration, Invasion by Targeting MARK1

Background

miRNA expression acts as a potential biomarker in many diseases including endometrial carcinoma (EC). miR-486-5p dysregulation is observed in several tumor types, but the roles of miR-486-5p in EC are hardly ever studied.

Objective

This study aimed to analyze the expression profile of miR-486-5p in tumor tissues and serum samples of patients with EC and explore the target prediction, function analysis and validation in immortal cell lines.

Patients and Methods

A total of 42 freshly paired EC tissues, the corresponding adjacent non-neoplastic tissues and serum samples were also collected from patients with EC, and 42 matched normal serum samples were included as control group. The level of miR-486-5p expression was tested by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was determined by colony formation assay and CCK-8 assay. Furthermore, functional evaluation of miR-486-5p on migration was performed by wound-healing assay and invasion was estimated by transwell invasion assay. qRT-PCR, luciferase reporter assay and Western blotting (WB) were performed to verify the targeting of MARK1 by miR-486-5p.

Results

miR-486-5p was significantly up-regulated in EC tissues and serum samples, promoting the proliferation, migration and invasive activities of EC cells by targeting MARK1.

Conclusion

These data indicated miR-486-5p as a novel molecular biomarker for diagnosing and treating EC, and MARK1 might act as a critical and functional target of miR-486-5p with the implications on cell proliferation, migration and invasiveness of EC tumor cells.

The differential expression of miRNAs between ovarian endometrioma and endometriosis-associated ovarian cancer

Background

MicroRNAs (miRNAs) have been implicated to play a vital role in development, differentiation, cell proliferation and apoptosis. However, which miRNAs are actually associated with endometriosis-associated ovarian cancer remains controversial.

Methods

Serum and ascites samples were obtained from all patients. Serum samples from 5 cases of ovarian endometrioma and endometriosis-associated ovarian cancer each were submitted for comprehensive miRNA microarray profiling. We investigated the differential expression of miRNAs between the two groups to confirm the pivotal role of miRNAs. Quantitative reverse transcription-polymerase chain reaction validation of five selected miRNAs [miR-92a-3p, miR-486-5p, miR-4484, miR-6821-5p, and miR-7108-5p] was performed, and miR-486-5p expression analysis was followed by proliferation and wound healing assays, depending on the expression of miR-486-5p.

Result

miR-486-5p expression in serum and ascites samples from endometriosis-associated ovarian cancer patients was significantly higher than that from ovarian endometrioma patients. Moreover, the miR-486-5p level in serum and ascites samples was significantly correlated with the severity of the endometriosis. The upregulation of miR-486-5p in immortalized ovarian endometrioma cells significantly increased proliferation and migration. In contrast, the downregulation of miR-486-5p in these cells significantly decreased proliferation and migration.

Conclusion

miR-486-5p might function as an oncogenic miRNA in endometriosis-associated ovarian cancer and could be a noninvasive biomarker to prospect the severity of ovarian endometrioma.

KIAA1199, a Target of MicoRNA-486-5p, Promotes Papillary Thyroid Cancer Invasion by Influencing Epithelial-Mesenchymal Transition (EMT)

Background

KIAA1199 has been reported to be associated with malignant progression and poor clinical outcomes in various human malignancies. However, its clinical role and molecular function remain unknown in papillary thyroid cancer (PTC).

Material/Methods

The Cancer Genome Atlas (TCGA) was used to investigate the expression profiles of KIAA1199 and miR-486-5p in PTC. Immunohistochemistry was used to validate the protein expression of KIAA1199 in PTC. The Weighted Gene Co-expression Network Analysis (WGCNA) and Gene Set Enrichment Analysis (GSEA) were used to explore the potential pathway underling KIAA1199 in PTC. In vitro and in vivo experiments were performed to investigate the biological role of KIAA1199 in PTC progression. Luciferase reporter assays and Western blot analysis were performed to determine whether KIAA1199 is a downstream target of miR-486-5p.

Results

We found that KIAA1199 was aberrantly elevated in PTC tissues compared with normal tissues, and upregulation of KIAA1199 was positively correlated with more advanced clinical variables. Additionally, bioinformatic analysis indicated that KIAA1199 was involved in cell migration and invasion. KIAA1199 silencing inhibited the invasive ability of PTC cells by affecting epithelial-mesenchymal transition (EMT) in vitro and in vivo. Furthermore, miR-486-5p was identified as an upstream microRNA that directly targets the 3′-UTR region of KIAA1199.

Conclusions

The miR-486-5p/KIAA1199/EMT axis might play a critical role in PTC invasion and metastasis and offers a potential therapeutic strategy for PTC.

Expression of miR-486-5p and its significance in lung squamous cell carcinoma

Lung squamous cell carcinoma (LUSC) is one of the main histological types of lung cancer with high mortality. The role of microRNA-486-5p in LUSC remains unclear. In the current study, the aim was to explore miR-486-5p expression and its role in LUSC. The miR-486-5p expression was significantly low-expressed in patients with LUSC from The Cancer Genome Atlas database, which was further confirmed in the Gene Expression Omnibus database, patients' tissues, different cell lines by quantitative real-time polymerase chain reaction, and the high-throughput gene sequencing data of lung tissues of mice after a long-term B(a)P exposure. The meta-analysis was performed to evaluate the expression and diagnosis power of miR-486-5p (standard mean difference = -2.25; 95% confidence interval: -3.47 to -1.03; P = 0.0003; area under curve = 0.9082). Functional enrichment analysis revealed the potential function of miR-486-5p in LUSC using gene set enrichment analysis and clusterProfiler package in R software. At last, the hub genes (PTEN, TEK, PIK3R1, PPM1B, SMAD2, and SPTA1) of miR-486-5p were verified. In conclusion, miR-486-5p may be a LUSC antioncogene, playing an important role to serve as a biomarker in LUSC.

MiR-486-5p inhibits the proliferation of leukemia cells and induces apoptosis through targeting FOXO1

AIM

Studies have reported that micro (miR)-486-5p plays a crucial part in the progression of leukemia, however, to the best of our knowledge, few studies have been conducted on its mechanism in leukemia. In this study, the mechanism of miR-486-5p in leukemia cells was pointed out and its possible target genes were analyzed for the purpose of providing new therapeutic strategies for treating leukemia patients.

METHODS

MiRNA expression of Leukemia cells (K562, Kasumi-1, and THP-1) and primary leukocytes was detected by Real-time Quantitative polymerase chain reaction(qPCR). The activity of the cells was assessed using the Cell Counting Kit-8 (CCK-8). Apoptotic cells were analyzed by a flow cytometer (FCM). Caspase-3 activation in leukemia cells was determined by Western blot. Targetscan 7.2 was used to predict the potential targets of miR-486-5p and further confirmed by dual-luciferase reporter assay.

RESULT

miR-486-5p was significantly down-regulated in leukemia cells. The over-expression of miR-486-5p notably increased the apoptosis and caspase-3 activity in leukemia cells. There was a predicted interaction site for miR-486-5p in the FOXO1 3'-UTR. Furthermore, this study showed that FOXO1 was significantly up-regulated in leukemia cells, the growth of which was depressed by the up-regulation of miR-486-5p.

CONCLUSION

miR-486-5p may inhibit the proliferation of leukemia cells and induce apoptosis through targeting FOXO1.

Liquid biopsy: miRNA as a potential biomarker in oral cancer

Oral cancer is one of the leading cancers in South-Asian countries. Despite the easy access of the oral cavity, the detection and five year survival rates of OSCC patients are dismal. Identification of non-invasive biomarkers to determine the progression and recurrence of OSCC could be of immense help to patients. Recent studies on oral cancer suggest the importance of non-invasive biomarker development. Micro-RNAs (miRNAs) are one of the important components of the cell-free nucleic acids available in different body fluids. Here, we have reviewed the current understanding of circulating miRNAs as non-invasive biomarkers in different body fluids of oral cancer patients. A number of circulating miRNAs are found to be common in the body fluids of OSCC patients, while many of these are study specific, the possible sources of this variability could be due to differences in sample processing, assay procedure, clinical stage of the disease, oral habit and environmental factors. The prognostic and therapeutic significance of these circulating miRNAs are suggested by several studies. Mir-371, mir-150, mir-21 and mir-7d were found to be potential prognostic markers, while mir-134, mir-146a, mir-338 and mir-371 were associated with metastases. The prognostic markers, mir-21 and mir-7d were also found to be significantly correlated with resistance to chemotherapy, while mir-375, mir-196 and mir-125b were significantly correlated with sensitivity to radiotherapy. Despite the promising roles of circulating miRNAs, challenges still remain in unravelling the exact regulation of these miRNAs before using them for targeted therapy.

Role of miR-486-5p in regulating renal cell carcinoma cell proliferation and apoptosis via TGF-β-activated kinase 1

Renal cell carcinoma (RCC) is a common kidney tumor in adults. The role of miR-486-5p in RCC is unknown. The aim of our study was to identify new targets regulated by miR-486-5p in RCC, to obtain a deeper insight into the network and to better understand the role of these microRNAs and their targets in carcinogenesis of RCC. We performed a series of tests and found consistently lower expression levels of miR-486-5p in kidney cancer cells. Restoration of miR-486-5p expression in RCC cells could lead to the suppression of cell proliferation and the increase of cell apoptosis. Further studies demonstrated that TGF-β-activated kinase 1 was a target gene of miR-486-5p in kidney cancer cells. It was also shown that C-C motif chemokine ligand 2 (CCL2) from tumor-associated macrophages downregulated miR-486-5p expression, and miR-486-5p inhibited RCC cell proliferation and apoptosis resistance induced by CCL2. The study demonstrates that there are potential diagnosis and therapy values of miR-486-5p in RCC.

S-Adenosylmethionine regulates apoptosis and autophagy in MCF-7 breast cancer cells through the modulation of specific microRNAs

Background

To get insight into the molecular mechanisms underlying the anti-tumor activity of S-adenosyl-l-methionine (AdoMet), we analyzed AdoMet-induced modulation of microRNAs (miRNAs) expression profile in MCF-7 breast cell line and its correlation with cancer-related biological pathways.

Methods

MiRNA expression profiling was performed using a TaqMan MiRNA Array, following 500 µM AdoMet-treatment. The results were confirmed by Quantitative real-time PCR analysis. MCF-7 were transfected with miR-34a, miR-34c and miR-486-5p, mimics and inhibitors in presence or not of 500 µM AdoMet for 72 h. Apoptosis and autophagy were analyzed by flow cytometry and the modulation of the main antiproliferative signaling pathways were evaluated by Western blotting. The potential mRNA targets for each miRNA were identified by the TargetScan miRNA target prediction software.

Results

Twenty-eight microRNAs resulted differentially expressed in AdoMet-treated MCF-7 cells compared to control cells. Among them, miRNA-34a and miRNA-34c were up-regulated while miRNA-486-5p was down-regulated. Moreover, we confirmed the ability of AdoMet to regulate these miRNAs in MDA-MB 231 breast cancer cell line. We demonstrate that, in MCF7 cells, the combination of either miR-34a or miR-34c mimic with AdoMet greatly potentiated the pro-apoptotic effect of AdoMet, by a caspase-dependent mechanism and activates p53 acetylation by inhibiting SIRT1 and HDAC1 expression. We also showed that miR-486-5p inhibitor induces autophagy and enhances AdoMet-induced autophagic process by increasing PTEN expression and by inhibiting AKT signaling.

Conclusions

Our findings provide the first evidence that AdoMet can regulate miRNA expression in MCF-7 increasing our knowledge on the molecular basis of the antitumor effect of the sulfonium compound and suggest the use of AdoMet as an attractive miRNA-mediated chemopreventive and therapeutic strategy in breast cancer.

DNA-methylation-mediated silencing of miR-486-5p promotes colorectal cancer proliferation and migration through activation of PLAGL2/IGF2/β-catenin signal pathways

As one of the most common cancers worldwide, colorectal cancer (CRC) causes a large number of mortality annually. Aberrant expression of microRNAs (miRNAs) is significantly associated with the initiation and development of CRC. Further investigations regarding the regulatory mechanism of miRNAs is warranted. In this study, we discovered that miR-486-5p was remarkably downregulated in CRC, which partially results from higher DNA methylation in the promoter region detected by using methylation-specific PCR, bisulfite sequencing PCR, and DNA demethylation treatment. Besides, decreased miR-486-5p was obviously associated with advanced TNM stage, larger tumor size, lymphatic metastasis, and poor prognosis in CRC. Upregulated miR-486-5p inhibited the proliferation and migration of CRC through targeting PLAGL2 expression and subsequent repressing IGF/β-catenin signal pathways both in vitro and in vivo. Notably, plasma miR-486-5p expression was significantly upregulated in CRC patients and we identified plasma miR-486-5p as a novel diagnostic biomarker of CRC using receiver operating characteristic (ROC) curve analysis. Moreover, exploration in GEO dataset revealed that circulating miR-486-5p is tumor derived through being packaged into secretory exosomes. Taken together, our data demonstrated that miR-486-5p promotes colorectal cancer proliferation and migration through activation of PLAGL2/IGF2/β-catenin signal pathway, which is a promising therapeutic target of CRC treatment.

Interplay between miRNAs and host genes and their role in cancer

MicroRNAs (miRNAs) are small endogenous non-coding functional RNAs that post-transcriptionally regulate gene expression. They play essential roles in nearly all biological processes including cell development and differentiation, DNA damage repair, cell death as well as intercellular communication. They are highly involved in cancer, acting as tumor suppressors and/or promoters to modulate cell proliferation, epithelial-mesenchymal transition and tumor invasion and metastasis. Recent studies have shown that more than half of miRNAs are located within protein-coding or non-coding genes. Intragenic miRNAs and their host genes either share the promoter or have independent transcription. Meanwhile, miRNAs work as partners or antagonists of their host genes by fine-tuning their target genes functionally associated with host genes. This review outlined the complicated relationship between intragenic miRNAs and host genes. Focusing on miRNAs known as oncogenes or tumor suppressors in specific cancer types, it studied co-expression relationships between these miRNAs and host genes in the cancer types using TCGA data sets, which validated previous findings and revealed common, tumor-specific and even subtype-specific patterns. These observations will help understand the function of intragenic miRNAs and further develop miRNA therapeutics in cancer.

MicroRNA-486-5p suppresses TGF-β2-induced proliferation, invasion and epithelial-mesenchymal transition of lens epithelial cells by targeting Smad2

The pathological development of lens epithelial cells (LECs) leads to posterior capsular opacification (PCO). This study was undertaken to investigate the effects of microRNA-486-5p (miR-486-5p) on TGF-β2-induced proliferation, invasion and epithelial-mesenchymal transition (EMT) in the lens epithelial cell line SRA01/04, and to explore the underlying molecular mechanisms. The expression of miR-486-5p in TGF-β2-induced SRA01/04 cells was down-regulated, and the expression of Smad2, p-Smad2 and p-Smad3 was up-regulated. A dual-luciferase reporter assay revealed that miR-486-5p directly targets the 30'-UTR of Smad2. MiR-486-5p mimic transfection markedly down-regulated the expression levels of Smad2, thus inhibiting the expression of p-Smad2 and p-Smad3. MiR-486-5p overexpression in SRA01/04 cells markedly suppressed TGF-β2-induced proliferation and invasion, inhibited protein expression of CDK2 and CDK4, down-regulated fibronectin, α-SMA and vimentin and up-regulated E-cadherin; these effects were partly reversed by Smad2 overexpression. In short, these data show that miR-486-5p overexpression can inhibit TGF-β2-induced proliferation, invasion and EMT in SRA01/04 cells by repressing Smad2/Smad3 signalling, implying that miR-486-5p may be an effective target to interfere in the progression of PCO.

Association of the peripheral blood levels of circulating microRNAs with both recurrent miscarriage and the outcomes of embryo transfer in an in vitro fertilization process

BACKGROUND

Implantation failure is not only a major cause of early pregnancy loss, but it is also an obstacle to assisted reproductive technologies. The identification of potential circulating biomarkers for recurrent miscarriage (RM) and/or recurrent implantation failure would contribute to the development of novel diagnosis and prediction techniques.

METHODS

MiR (miR-23a-3p, 27a-3p, 29a-3p, 100-5p, 127-3p and 486-5p) expression in the villi, decidual tissues and peripheral blood plasma and serum were validated by qPCR, and the localization of miRs in the villi and decidual tissues of RM and normal pregnancy (NP) women were detected by in situ hybridization. The invasiveness of HTR8/SVneo cells was determined using a Transwell assay. The predictive values of miRs for RM and the outcome of IVF-ET were respectively calculated by the receiver operating characteristic analysis.

RESULTS

The signals of six miRs were observed in the villi and decidual tissues of RM and NP women. The villus miR-27a-3p, miR-29a-3p and miR-100-5p were significantly up-regulated, whereas miR-127-3p and miR-486-5p appeared to be down-regulated in RM women compared to NP women. The invasiveness of HTR8/SVneo cells transfected with miR-23a-3p mimics was evidently weakened, whereas that of cells transfected with miR-127-3p mimics was obviously enhanced. The peripheral blood plasma levels of miR-27a-3p, miR-29a-3p, miR-100-5p and miR-127-3p were significantly increased, whereas that of miR-486-5p was remarkably decreased in RM compared to NP women. By contrast, serum miR-23a-3p and miR-127-3p were significantly decreased, whereas that of miR-486-5p was remarkably increased. The combination of six plasma miRs levels discriminated RM with a sensitivity of 100% and a specificity of 83.3%, whereas that of six serum miRs levels showed a sensitivity of 78.3% and a specificity of 93.1%. In the IVF-ET cohort, the significantly decreased peripheral blood plasma levels of miR-23a-3p, miR-27a-3p, miR-100-5p and miR-127-3p, and the serum levels of miR-100-5p and miR-486-5p, in addition to the significantly increased serum level of miR-27a-3p, were found to be associated with the failure of ET. Moreover, the combination of plasma miR-23a-3p, miR-27a-3p, miR-29a-3p, miR-100-5p, miR-127-3p and miR-486-5p levels discriminated the outcome of IVF-ET with a sensitivity of 68.1% and a specificity of 54.1%, whereas the combination of plasma miR-127-3p and miR-486-5p levels showed a sensitivity of 50.0% and a specificity of 75.3%.

CONCLUSIONS

Circulating miR-23a-3p, miR-27a-3p, miR-29a-3p, miR-100-5p, miR-127-3p and miR-486-5 might be involved in RM pathogenesis and present potential diagnostic biomarkers for RM. Meanwhile, these miRs, in particular miR-127-3p and miR-486-5p, provide promising prediction indexes for the outcomes of IVF-ET.

miR-486-5p inhibits cell proliferation and invasion through repressing GAB2 in non-small cell lung cancer

Previous studies have reported that cell metastasis is the main reason for the high mortality of non-small cell lung cancer (NSCLC). Many miRNAs have been identified to be involved in the development of NSCLC. In this study, we explored the effect of miR-486-5p and GAB2 on cell proliferation and invasion in NSCLC. First, miR-486-5p and GAB2 expression levels were detected in NSCLC through quantitative RT-qPCR, and downregulation of miR-486-5p and upregulation of GAB2 were both identified in NSCLC. Then MTT and Transwell analysis were performed to confirm the functions of miR-486-5p and GAB2 for cell proliferation and invasion in NSCLC. Moreover, miR-486-5p overexpression was found to inhibit proliferation and invasion by suppressing GAB2 in NSCLC cells. Besides, miR-486-5p overexpression lessened GAB2 expression level in NSCLC, while miR-486-5p knockout enhanced GAB2 expression level. Additionally, miR-486-5p was identified to directly target GAB2 through dual luciferase reporter assay. The silence of GAB2 was found to inhibit proliferation and invasion of NSCLC cells. Collectively, miR-486-5p contributed to inhibiting proliferation and invasion of NSCLC cells through regulating GAB2, and miR-486-5p/GAB2 axis may provide a breakthrough for diagnosing NSCLC.

Identification of key genes and pathways for esophageal squamous cell carcinoma by bioinformatics analysis

The aim of the present study was to identify the differentially expressed genes (DEGs) in esophageal squamous-cellcarcinoma (ESCC) and provide potential therapeutic targets. The microarray dataset GSE20347 was downloaded from the Gene Expression Omnibus (GEO) database, and included 17 tissue samples and 13 normal adjacent tissue samples from patients with ESCC. A total of 22,277 DEGs were identified. A heat map for the DEGs was constructed with the Morpheus online tool and the top 200 genes (100 upregulated and 100 downregulated) were selected for further bioinformatics analysis, including analysis of gene ontology (GO) terms, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, protein-protein interaction networks and Spearman's correlation tests. The results of the GO analysis indicated that the upregulated DEGs were most significantly enriched in membrane-bounded vesicles in the cellular component (CC) category, but were not significantly enriched in any GO terms of the categories biological process (BP) or molecular function (MF); furthermore, the downregulated DEGs were most significantly enriched in regulation of DNA metabolic processes, nucleotide binding and chromosomes in the categories BP, MF and CC, respectively. The KEGG analysis indicated that the downregulated DEGs were enriched in the regulation of cell cycle pathways. The top 10 hub proteins in the protein-protein interaction network were cyclin-dependent kinase 4, budding uninhibited by benzimidazoles 1, cyclin B2, heat shock protein 90AA1, aurora kinase A, H2A histone family member Z, replication factor C subunit 4, and minichromosome maintenance complex component 2, −4 and −7. These proteins are mainly involved in regulating tumor progression. The genes in the four top modules were mainly implicated in regulating cell cycle pathways. Secreted Ly-6/uPAR-related protein (SLURP) was the hub gene, and SLURP and its interacting genes were most enriched in the chromosomal part in the CC category, organelle organization in the BP category and protein binding in the MF category, and were involved in pathways including DNA replication, cell cycle and P53 signaling. The expression of SLURP-1 in fifteen patients with esophageal carcinoma was detected using quantitative polymerase chain reaction analysis, and the results indicated that SLURP-1 expression was significantly decreased in the tumor samples relative to that in normal adjacent tissues. These results suggest that several hub proteins and the hub gene SLURP-1 may serve as potential therapeutic targets, and that gene dysfunction may be involved in the tumorigenesis of ESCC.

MicroRNA-125b inhibits cell proliferation and induces cell apoptosis in esophageal squamous cell carcinoma by targeting BMF

MicroRNAs (miRNAs) have been reported to regulate the expression of genes by suppressing translation or facilitating mRNA decay. Their expression regulates a wide variety of cellular processes, including the development and progression of cancer. Esophageal squamous cell carcinoma (ESCC) is a malignant cancer with high morbidity and recurrence in Asia. In the present study, the biological function of miR-125b and its underlying mechanism in ESCC were explored. The results revealed that miR-125b expression was significantly decreased in ESCC tissues and cell lines. A decrease in miR-125b was markedly related to lymphatic metastasis in patients. Functional analysis revealed that the overexpression of miR-125b using miR-125b mimics significantly inhibited cell growth and induced cell apoptosis, and increased the G1 phase of the cell cycle in EC109 and EC9706 cells. Notably, the miR-125b inhibitors revealed the opposite effect. Additionally, overexpression of miR-125b significantly inhibited tumor growth in vivo. Furthermore, BCL-2-modifying factor (BMF) was considered to be a potential candidate target of miR-125b based on miRNA target databases. miR-125b negatively regulated BMF expression by directly binding to its 3′-untranslated region. BMF was a functional target of miR-125b in the regulation of cell proliferation, cell apoptosis and the cell cycle in EC109 and EC9706 cells. In clinical ESCC specimens, BMF expression was upregulated, and negatively correlated with that of miR-125b. In conclusion, miR-125b had an antitumor role in ESCC cells mediated by targeting BMF, which can be potentially useful for tumorigenesis in ESCC.

Elevated circulating miR-182 acts as a diagnostic biomarker for early colorectal cancer

Purpose

Globally, colorectal cancer (CRC) is one of the most common cancers with high mortality. Although CRC patients in stages I–II are curable after surgical resection, due to the lack of sensitive and specific biomarkers, many patients are in the advanced stages when diagnosed. This study aimed to investigate whether circulating miRNAs in plasma could act as biomarkers for early CRC diagnosis.

Patients and methods

All healthy subjects and patients were from Nanjing First Hospital. We first selected 2 differential miRNAs by integrated analysis of 4 Gene Expression Omnibus (GEO) data sets and The Cancer Genome Atlas (TCGA) database. Next, the expression of these 2 miRNAs in tissue and plasma samples were examined through quantitative real-time polymerase chain reaction. Training phase and validation phase were designed to investigate the diagnostic utility of these differential miRNAs using receiver operating characteristic (ROC) curve analysis.

Results

After integrated analysis of 4 GEO and TCGA databases, upregulated miR-182 and miR-20a were selected to further investigate their diagnostic potential for CRC. We discovered that miR-182 and miR-20a were upregulated in CRC tissue and plasma and that circulating miR-182 and miR-20a in the plasma of CRC patients were tumor derived. The area under the ROC curve (AUC) of circulating miR-182 was 0.929 (95% CI 0.875–0.983) in the training phase and 0.891 (95% CI 0.821–0.961) in the validation phase. The AUC of circulating miR-20a expression was 0.801 (95% CI 0.695–0.906) in the training phase and 0.736 (95% CI 0.631–0.842) in the validation phase.

Conclusion

Circulating miR-182 is a novel potential biomarker for early CRC diagnosis.

MiR-486 as an effective biomarker in cancer diagnosis and prognosis: a systematic review and meta-analysis

Purpose

MiR-486 was found to be associated with cancer’s diagnosis and prognosis. This meta-analysis aimed to investigate the potential effect of miR-486 on cancer detection and prognosis.

Materials and Methods

We searched PubMed, Cochrane library, Embase, Chinese National Knowledge Infrastructure (CNKI) and Wanfang databases to find all correlated articles. The STATA 11.0 was applied to estimate the pooled effects, heterogeneity and publication bias.

Results

The pooled sensitivity (SEN), specificity (SPE) and Area under the curve (AUC) were 82% (95% CI: 78–85%), 88% (95% CI: 83–92%) and 0.91 (95% CI: 0.88–0.93). Subgroup analysis indicated miR-486 from circulating samples exhibited higher diagnostic accuracy with the AUC was 0.90 (95% CI: 0.87–0.92) than miR-486 from other specimen with the AUC of 0.78 (95% CI: 0.75–0.82) and miR-486 obtained a better diagnostic value in the Asian population with the AUC of 0.94 (95% CI: 0.91–0.95) than the Caucasian and Caucasian/African population with the AUC of 0.80 (95% CI: 0.76–0.83) and 0.89 (95% CI: 0.86–0.91) respectively. MiR-486 obtained high value for the diagnosis of non-small cell lung cancer with SEN, SPE and AUC were 0.82 (95% CI: 0.0.77–0.87), 0.90 (95% CI: 0.84–0.94) as well as 0.92 (95% CI: 0.89–0.94) respectively. For the 7 prognostic tests, the pooled hazard ratio (HR) was 0.48 (95% CI: –0.13–1.08) for low versus high miR-486 expression.

Conclusions

This meta-analysis indicated that miR-486 can be used as ideal biomarkers in the cancer’s diagnosis. However, Low miR-486 expression did not increase the risk of poor outcome.

miR-486 functions as a tumor suppressor in esophageal cancer by targeting CDK4/BCAS2

Esophageal cancer is a common tumor for which morbidity and mortality are high worldwide. We aimed to study alterations in miR-486 expression in esophageal cancers, and the effect miR-486 on esophageal cancer cell function and behavior. We collected esophageal cancer tissues/corresponding normal tissues from 20 patients and utilized three esophageal cancer cell lines and normal esophageal epithelial cells, and the expression of miR-486, CDK4 and BCAS2 was detected by qRT-PCR. Western blotting was used to detect the expression of CDK4 and BCAS2 protein. Then, we overexpressed miR-486 in esophageal cancer cell line EC9706. A series of cell functional analyses, including cell growth, cell cycle, apoptosis, migration and invasion were performed in esophageal cancer cells using colony formation assay, flow cytometry, Transwell and scratch assays, respectively. Dual-Luciferase reporter gene assay was used to detect the target genes of miR-486. We found that the expression of miR-486 in esophageal cancer tissues and cell lines was significantly lower than that in the normal tissues and normal esophageal epithelial cell line. Overexpression of miR-486 significantly inhibited the colony formation ability, induced G0/G1 phase arrest and apoptosis and suppressed cell migration and invasion in the EC9706 cells. Using bioinformatics and luciferase reporter assay, we identified that CDK4 and BCAS2 may be target genes of miR-486 and levels of CDK4 and BCAS2 were both significantly higher in the esophageal cancer tissues and cell lines than levels in the normal tissues and cells. Furthermore, knockdown of CDK4/BCAS2 coincided with the suppressive effects of miR-486 in esophageal cancer cells. Expression of apoptotic signaling molecules p21 and caspase-3 was upregulated in the CDK4/BCAS2-knockdown groups. These results suggest that miR-486 may suppress tumor cell growth and metastasis in esophageal cancer by targeting CDK4/BCAS2. The newly identified miR-486/CDK4/BCAS2 pathway provides further insight into the development and progression of esophageal cancer, which is of great significance to the early diagnosis and detection of esophageal cancer.

miR-382 functions as a tumor suppressor against esophageal squamous cell carcinoma

AIM

To explore the effect of miR-382 on esophageal squamous cell carcinoma (ESCC) in vitro and its possible molecular mechanism.

METHODS

Eca109 cells derived from human ESCC and Het-1A cells derived from human normal esophageal epithelium were used. Lentivirus-mediated miR-382 was overexpressed in Eca109 cells. The effect of miR-382 on cell proliferation was evaluated by MTT and colony formation assay. For cell cycle analysis, cells were fixed and stained for 30 min with propidium iodide (PI) staining buffer containing 10 mg/mL PI and 100 mg/mL RNase A, and analyzed by BD FACSCalibur™ flow cytometer. For cell apoptosis assay, cells were stained with an Annexin V-FITC/PI Apoptosis Detection Kit according to the manufacturer’s instructions and analyzed by a dual-laser flow cytometer. Cell invasion and migration abilities were determined through use of transwell chambers, non-coated or pre-coated with matrigel. Levels of proteins related to cell growth and migration were examined by western blotting.

RESULTS

Endogenous miR-382 was down-regulated in Eca109 cells compared with Het-1A. Introduction of miR-382 not only significantly inhibited proliferation and colony formation, but also arrested cell cycle at the G2/M phase, as well as promoted apoptosis and autophagy in Eca109 cells. Migration, invasion and epithelial-mesenchymal transition of Eca109 cells were suppressed by overexpressing miR-382. Western blotting results showed that miR-382 inhibited the phosphorylation of mTOR and 4E-BP1.

CONCLUSION

miR-382 functions as a tumor suppressor against ESCC development and metastasis, and could be considered as a potential drug source for the treatment of ESCC patients.