IFNG and colorectal carcinoma: TCF7L2 was found to be under-expressed in the high-risk cluster, the loss-of-function mutation of which has been reported to be strongly associated with the risk of CRC.39 Conversely, SFRP4 was overexpressed and may be a gain-of-function mutation in the high-risk cluster.40 Genes co-expressed with SFRP4 in stage II patients of the TCGA cohort were enriched in “epithelial–mesenchymal transition signalling” and EMT-related functional gene sets (GSEA analysis), such as “apical junction” and “interferon gamma signalling”, suggesting that SFRP4 may be a driver gene for metastasis of CRC patients.