In our previous research, we analysed the CRC gene expression profile data of GSE41258 and sifted out a number of differentially expressed genes in which the expression of IPO5 was continuously increasing with the increasing severity from normal tissues to stage I, stage II, stage III, stage IV, and liver metastasis tumours (Additional file 1: Figure S1A) [12]. This evidence concerns the gene IPO5 and neoplasm.