Identification of key tumorigenesis-related genes and their microRNAs in colon cancer

Colorectal cancer (CRC) is one of the most common malignant tumors and its development involves multi-gene driven processes that affect the digestive system. The objective of this study was to identify tumorigenesis-associated gene signatures using microarray expression profiling data. The gene expression profiling of GSE39582, a dataset containing 566 colon cancer samples and 19 non-tumoral colorectal mucosae was downloaded from Gene Expression Omnibus (GEO) database. A total of 439 differentially expressed genes (DEGs) were extracted by GEO2R. Many of these DEGs were cancer-related, involved in the regulation of cell proliferation, extracellular matrix (ECM)-receptor interaction and phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway according to the results of pathway enrichment analysis in Database for Annotation, Visualization and Integrated Discovery (DAVID). Then, 10 genes were predicted to play an important role in the development of CRC. Transient receptor potential cation channel, subfamily M, and member 6 (TRPM6), a member of 10 hub genes, was confirmed to be downregulated in 16 (80%) of 20 colon cancer tissues using quantitative polymerase chain reaction (qPCR) technology. Furthermore, high expression of TRPM6 was indicative of a prolonged overall survival (OS) in CRC patients through the analysis of GSE39582. Hsa-let-7g and hsa-let-7f-1 were believed to be the regulatory miRNAs of TRPM6 by TCGA and miRanda database. In conclusion, this study may play a critical role in promoting the discovery of potential targets for diagnosis, treatment and prognosis of CRC.