The Different Expression Of MiR-34a、MiR-148a And Wntl Between Human Breast Carcinoma And Normal Breast Tissue

Objective:Look for clues in miR-34a and miR-148a target Wntl gene by literature searching and bioinformatics. Use molecular biology techniques to analyse the expression and study the correlation between miR-148a、miR-34a and Wntl mRNA、Wntl protein in breast carcinoma tissue and normal breast tissue. Our study will contribute to further research about the function of miR-148a、miR-34a and Wntl during breast cancer pathogenesis. Our study also can provide a new line and an experimental basis for the molecular mechanism involved in breast cancer development and progression and gene therapy of breast carcinoma.Methods:1.Three online softwares for bioinformatics analysis, i.e., PicTar, TargetScan and microRNA.org were used for searching miRNAs which might target Wntl.2.The varying levels of miR-34a、miR-148a and Wntl mRNA were assessed by semiquantitative reverse transcription-polymerase chain reaction(RT-PCR) and real-time quantitative reverse transcription-polymerase chain reaction(qRT-PCR); the levels of Wntl protein were valued by immunohistochemistry and Western-blot.Results:1.After literature searching and bioinformatics we had a preliminary result that miR-34a and miR-148a might target Wntl gene. We found that miR-34a and miR-148a had target sites in the3’-UTR of Wntl mRNA by miRNA binding site prediction program. 2.Compared with the normal group, the miR-34a and miR-148a expression decreased in breast carcinoma group; the Wntl mRNA amount increased in breast carcinoma group, as well as Wntl protein. There were significantly negative correlations between the expression of miR-34a、miR-148a and Wntl mRNA in the two groups.Conclusions:These results suggest that miR-34a and miR-148a express lower in breast cancer group than the control group. miR-34a and miR-148a may downregulate the amount of Wntl mRNA in the post-transcriptional level, and lead to the increase of Wntl protein in breast carcinoma. The changes of miR-34a、miR-148a and Wntl expressions may be related to the breast cancer pathogenesis.