The Expression And Biological Function Of Long Non-Coding RNA BCYRN1 In Esophageal Squamous Cell Carcinoma

BackgroundEsophageal cancer which is originated from esophageal epithelial tissue is one of the most common malignant tumors.In 2015,there were about 477,000 newly diagnosed cases and 375,000 death cases in China.Esophageal carcinoma is mainly divided into two histological subtypes: squamous cell carcinoma and adenocarcinoma.Esophageal squamous cell carcinoma(ESCC)is the main histological subtype in China.Because of atypical early symptoms,esophageal carcinoma has been in the late stage and missed the best treatment opportunity when patients had emerged dysphagia.Although current diagnostic techniques,perioperative management and radiotherapy and chemotherapy have improved,the rate of metastasis and recurrence for esophageal cancer is still high,and the situation of the resistance to chemotherapy drugs,so the overall 5-year survival rate is still very low.Early detection and treatment can help to early diagnosis of esophageal cancer and improve the prognosis of esophageal cancer.Therefore,it is significant to explore and screen new and effective biomarkers for the diagnosis and treatment of esophageal cancer.Long noncoding RNAs(LncRNAs)are the major member of noncoding RNA in mammalian genomes.They are over 200 nt in length,lacking a complete open reading frame(ORF)and no protein encoding function.Although transcripts of LncRNAs cannot be translated into proteins,LncRNAs play an important role in epigenetic modification,transcriptional regulation,post-transcriptional regulation and protein translation.In recent years,studies have shown that LncRNAs are expressed abnormally in cancer and play an important role as oncogene or oncogenic suppressors.Therefore,the exploration of LncRNAs related to esophageal cancer has become one of the most important topics in this field.LncRNA BCYRN1(Brain Cytoplasmic RNA1,brain cytoplasmic RNA1)also known as BC200,is located on human chromosome 2p12,transcripted by RNA polymerase? and 200 nt long LncRNA.The previous studies have suggested that LncRNA BCYRN1 acts as a translation regulator to regulate the synthesis of synaptic dendritic proteins in neurons.Most expressed in the nervous and reproductive systems of primates.Recent studies have shown high levels of expression in breast,lung,cervical,ovarian,gastric,esophageal and tongue cancers.The abnormal expression of Lnc RNA BCYRN1 is involved in the proliferation,apoptosis,invasion and metastasis of cancer cells.However,there are few studies on the expression and biological function of LncRNA BCYRN1 in ESCC.The purpose of this study was to detect the expression of LncRNA BCYRN1 and its biological function in ESCC.ObjectivesTo investigate the expression level of LncRNA BCYRN1 and its biological function in ESCC.Methods1.Quantitative real-time polymerase chain reaction(qRT-PCR)was used to detect the expression level of Lnc RNA BCYRN1 in cancer tissues and paired adjacent normal tissues from 66 ESCC patients who had received radical resection.Expressions of BCYRN1 in human normal esophageal epithelial cell line(Het-1A)and human esophageal squamous cell carcinoma cell lines(EC9706,Eca109)were detected respectively by qRT-PCR.The ESCC cell lines of high level of LncRNA BCYRN1 were used in the following tests.2.For stable inhibition of BCYRN1,EC9706 cells were transfected with the lentiviral vector carrying BCYRN1-shRNA.MTT assays and micro scratch and Transwell tests were used to detect the proliferation,the invasion ability and migration ability of the transfected EC9706 cells.Results1.Expression levels of LncRNA BCYRN1 esophageal squamous cell carcinoma and cell lines EC9706 and Eca109 were increased.2.Determined by MTT assays results show that,with the negative control group(negative virus carrier,NC group)and compared with blank control group(MOCK group),BCYRN1-shRNA infected EC9706 cell proliferation activity of no significant change(P > 0.05);Micro scratch and Transwell tests showed that the migration and invasion ability of the EC9706 cells decreased after the interference of LncRNA BCYRN1(P < 0.05).Conclusions1.The expression level of LncRNA BCYRN1 in esophageal squamous cell carcinoma was higher than that of adjacent normal tissues.Based on two kinds of esophageal squamous cancer cells and normal esophageal epithelial cell lines in BCYRN1 detection,confirmed BCYRN1 EC9706 in esophageal squamous cancer cells and Eca109 expression is higher than normal esophageal epithelial cell lines expressed in Het-1A.2.The down expression of Lnc RNA BCYRN1 can reduce the expression of esophageal squamous cancer cell migration and invasion ability,shows that its plays the role of oncogene in esophageal squamous carcinoma,promote the esophageal squamous cell carcinomas of the migration and invasion,may be of potential therapeutic targets,provide the basis for subsequent clinical treatment of ESCC.