Identification of miRNA-miRNA synergistic relationships in colorectal cancer.

PURPOSE: A large list of microRNAs (miRNAs) which may play important roles in the tumorigenesis of colorectal cancer (CRC) were generated recently. The purpose of our study is to analyze the synergistic regulations among miRNAs which were differentially expressed in tumorigenesis of CRC.

METHODS: In this study, we downloaded the miRNA microarray and gene expression microarray of CRC from Gene Expression Omnibus (GEO), and identified the differentially expressed miRNAs (DE-miRNAs) and genes (DEGs) in cancer tissues compared with normal controls. In addition, we investigated the complex synergistic relationships among DE-miRNAs and constructed a miRNA-miRNA synergistic network by assembling all synergistic pairs.

RESULTS: A total of 32 DE-miRNAs formed 8 functional modules in the synergistic network. These miRNAs in functional modules could independently implement specific functions as a whole in CRC, such as endocytosis, cell cycle, and p53 signaling pathway.

CONCLUSIONS: The network allows for an in-depth analysis of individual miRNAs in the context of their synergistic surroundings.