Bioinformatic exploration for candidate miRNAs as breast cancer biomarkers

MicroRNAs (miRNAs) are key post-transcriptional regulators that affect protein translation by targeting mRNAs. The rapid advancement of next-generation sequencing techniques, miRNA profiling has been increasingly conducted with RNA-seq, namely miRNA-seq. miRNAs are a relatively new class of non-coding RNAs that have the potential as cancer biomarkers that are a group of molecules that can use for diagnosis and prognosis different types of cancer, like circulating and exosomal miRNA. To seek this purpose, information of miRNA seq for breast cancer were obtained from the GEO databank. Using miRNA seq data from thousands of paired tumor and adjacent diagnostic normal samples, we identified ten miRNA as biomarker candidate. The expression levels of these ten miRNAs that analyzed with R software are significantly different between tumor and normal samples. We further explored the function of candidate miRNAs with diana tools and realized that they have an important role in PI3K pathway in breast cancer.