Expression of MiR-148b-3p in Lung Adenocarcinoma and Its Correlation with Prognosis / 中国肺癌杂志

BACKGROUND@#MiR-148b-3p is an important microRNA that has been reported to be significantly related to various types of cancer, but its role in lung adenocarcinoma remains elusive. The purpose of this study is to detect the expression level of miR-148b-3p in lung adenocarcinoma specimens, and to analyze its correlation with the clinicopathological features as well as the prognosis of patients with lung adenocarcinoma.@*METHODS@#A total of 123 tumor specimens from lung adenocarcinoma patients who underwent surgical resection in our department from January 2011 to December 2012 were collected. The expression of miR-148b-3p was detected by quantitative real-time PCR (qRT-PCR), and its correlation with clinicopathological features of patients with lung adenocarcinoma was analyzed. Multivariate Cox proportional hazard models were used to analyze independent predictors of overall survival in patients with lung adenocarcinoma. The overall survival (OS) of patients in miR-148b-3p high expression group and miR-148b-3p low expression group were estimated by means of the Kaplan-Meier method and were compared using the Log-rank test method.@*RESULTS@#Of the 123 patients with lung adenocarcinoma, 71 were in miR-148b-3p high expression group and 52 in low expression group. MiR-148b-3p was significantly associated with tumor grade (P=0.001) and tumor size (P=0.007), but not with age, gender, smoking history, history of alcohol, tumor thrombus, pleural invasion, node status or metastasis status. Multivariate Cox proportional hazard model analysis showed that tumor size (P=0.032), node status (P=0.005) and miR-148b-3p expression level (P=0.047) were significant independent predictors of overall survival of patients with lung adenocarcinoma. Kaplan-Meier survival analysis showed that the overall survival of patients with high expression of miR-148b-3p was significantly better than that of patients with low expression (P=0.010).@*CONCLUSIONS@#MiR-148b-3p was significantly associated with tumor grade and tumor size in lung adenocarcinoma, and served as an independent predictor of overall survival of patients with lung adenocarcinoma. The overall survival of patients with high expression level of miR-148b-3p was significantly better than that of patients with low expression.

Chemotherapeutic drugs affect methylation of ER-α in breast cancer cells by down-regulating miR-148b / 中华内分泌外科杂志

Objective To investigate the effects of chemotherapeutic drugs on ER-α expression and methylation in breast cancer cells.Methods Human breast cancer cells MCF-7(ER+,Luminal A) were induced by paclitaxel(PTX) and epirubicin(EPI) for more than 6 months,with an incremental dose,respectively.The expression and methylation status of ER-α in MCF-7 cells were detected before and after drug treatment.miRNAs with consistent expression changes in MCF-7 cells after two drugs' treatment were screened by microarray,and verified by quantitative PCR (qPCR).Targets of the most significantly down-regulated miRNA were analyzed by bioinformatics.miRNA inhibitor was transfected into MCF-7 cells,miRNA mimic was transfected into MCF-7/PTX and MCF-7/EPI cells,then ER-α and DNA methyltransferase 1 (DNMT1) expression were detected by Western blot,and ER-α methylation was detected by quantitative methylation-specific PCR (qMSP).Results PTX resistant MCF-7/PTX cell line and EPI resistant MCF-7/EPI cell line were established.Both drug treatments caused a decrease in ER-α protein expression and an increase in methylation levels,with up-regulation of DNMT1 and his tone deacetylase 1 (HDAC 1) expression.miRNAs with consistent expression changes in MCF-7 cells after drug treatments were screened and verified by qPCR,the most significant down-regulation among which was miR-148b.Bioinformatics analysis,and further confirmed by luciferase reporter gene assay (Luciferas) that DNMT1 was a direct target of miR-148b.miR-148b inhibitor induced decreased expression of ER-α and increased methylation level in MCF-7 cells,accompanied by increased expression of DNMT1;whereas miR-148b mimic caused an increased expression of ER-α and decreased methylation level in MCF-7/PTX and MCF-7/EPI cells,with a decreased expression of DNMT1.Conclusion Chemotherapeutic drugs (represented by PTX and EPI) induce aberrant miRNA expression in breast cancer MCF-7 cells,and down-regulate miR-148b further to attenuate the inhibition of DNMT1 expression,which promote,hypermethylation and down-regulation of ER-α.

p53 inhibits the proliferation of lung cancer cell PC-9 by regulating miR-148b / 实用医学杂志

Objective To explore the function of p53 on regulating the expression of miR-148b in lung cancer cell line PC-9 and its corresponding molecular mechanism and the impact on cell proliferation. Methods Transient transfection of p53 eukaryotic expressing plasmids into lung cancer cell line PC-9 was performed to establish a cell model over-expressing p53. RT-PCR was used to explicit the impact of p53 on the expression of miR-148b. A reporter vector containing miR-148b promoter was used to investigate the function of p53 on regulating the transcription of miR-148b. Low-expressing miR-148b by transfecting its specific inhibitors , a CCK-8 assay was performed to explore the influence of miR-148b on the lung cancer cell proliferation inhibited by p53. Results Over-expression of p53 promoted miR-148b expression in lung cancer cell line PC-9. P53 could increase the luciferase activity driven by miR-148b promoters. Knockdown of miR-148b attenuated the impact of p53 on inhibiting the proliferation of PC-9 cells. Conclusion P53 inhibits the proliferation of lung cancer cell line PC-9 partially depending on miR-148b.