Study On The Differences Expression Of MicroRNA In Glioma

Background:Glioma (glioma) is the most common central nervous system tumors, and its incidence increases with age have a higher trend. Glioma was often invasive growth, has a strong attack capabilities, difficult to radical surgery and postoperative total resection of tumor recurrence is one of leading causes of death. Therefore, to study the occurrence and development mechanism, contribute to a better understanding of their biological behavior of tumors, in order to find better treatment strategies. Find new potential targets for drug intervention, has significance. miRNA is a newly discovered class of small RNA molecules, and its activities in life have played an important role in regulation. Abnormal expression of miRNAs with tumor occurrence and development are closely related. How to find more of the miRNA and its target gene research in the past few years, following small interfering RNA after one of the hot new research.Objective:To study the glioma tissue differences in miRNA expression level, to explore the occurrence and development of glioma play an important role in the miRNA and target genes. Further clarify the occurrence and development of glioma mechanisms and to find potential targets for glioma treatment.Methods:Fresh human glioma tissue samples six cases, non-tumor brain tissue of six cases, extraction of total RNA and miRNA, to adopt the Danish company Exiqon chip microRNA8.0 analysis for detection, screening differentially expressed miRNA,, using fluorescence quantitative RT -PCR validation of differentially expressed miRNA, the use of bioinformatics software analysis of differential expression of miRNA regulation of target genes, thus the use of RT-PCR and Western-blot method to verify target gene mRNA and protein expression levels, to explore the occurrence and development of glioma play an important role in the miRNA and target genes.Results:The experimental miRNA chip dual-channel system, the chip group repeated the experiment one time, inter-chip technology to repeat the experiment a total of 3 times. Application of non-hierarchical cluster analysis method to glioma and non-tumor brain tissue cluster analysis together with the non-neoplastic brain tissue compared to a total of 146 miRNAs in the glioma cells were significantly different, including 11 upward and 39 down-regulated expression with more obvious differences between miRNAs.Ⅰ～Ⅱlevel in the glioma/non-tumor brain tissue microarray of miRNAs differentially expressed in five significant increase of miRNAs::miR-122a, miR-296, miR-18b, miR-486, miR-150; 17 a downward adjustment of miRNAs:miR-106b, miR-503, miR-516-5p, miR-237, miR-15a, miR-21, miR-17b, miR-361, miR-67b, miR-107, miR-489, miR-330, miR-381, miR-96, miR-409-5p miR-195, miR- 200c. In gradeⅢ-Ⅳglioma organizations/non-tumor brain tissue microarray of miRNAs differentially expressed, the six significant increase of miRNAs:miR-486, miR-26a, miR-324-3p, miR-46c, miR-18b, miR-30d; 22 months significantly reduced the miRNAs:miR-130b, miR-235, miR-21, miR-433, miR-299-5p, miR-99b, miR-520a, miR-542-3p, miR-195, miR-487b, miR-487a, miR-170, miR-96, miR-324-5p, miR-206, miR-4c, miR-193b, miRNAs, miR-237, miR-208, miR-15b. Comparison ofⅠ～Ⅱgrade glioma/non-tumor brain tissue and glioma gradeⅢ～Ⅳorganizations/non-tumor brain tissue of two chips, with the same significant difference in the expression of miRNAs5 months (Ratio≥10):in which there is an upward adjustment miR-18b, miR-486; reduction of miR-237, miR-96, miR-21. Based on part of differentially expressed miRNAs target gene analysis to predict the target gene function involved in cell cycle, cell motility, tumor angiogenesis and so on. We choose to predict glioma cells down-regulated expression of miR-486 target genes PIRH2 and up-regulated expression of HDAC7 target genes miR21 using RT-PCR and western-blot method to verify the results showed that:PIRH2 mRNA and protein expression of water average significantly higher than non-neoplastic brain tissue (0.62±0.23 vs 0.26±0.29, P=0.020; 0.88±0.30 vs 0.22±0.26, P=0.004), statistically significant differences (P<0.05). And HDAC7 mRNA and protein expression was significantly higher than non-neoplastic brain tissue (0.48 ±0.24 vs 0.70±0.18, P=0.010; 0.64±0.17 vs 0.91±0.23, P=0.003) difference was statistically significant (P<0.05).Conclusion:The existence of glioma cells differentially expressed miRNA, such miRNA, including a significant increase of miR-18b, miR-486; significant reduction of miR-237, miR-96, miR-21, miR-18b, miR-486, prompted these miRNA may be related to the occurrence of glioma development. Target gene prediction software using analysis of glioma cells differentially expressed miRNA, found their target gene regulation and control a very wide range of genes involved in cancer, cell cycle, cell differentiation, transcriptional regulation, etc., in which down-regulated expression of miR-486 target gene regulation PIRH2 rates and up-regulated expression of miR-21 target gene regulation mechanism of HDAC7 downward, and then take part in the occurrence and development of glioma.