As expected, tumor-derived organoids highly expressed in vivo tumor-specific genes, many of which have been widely reported to be closely related to colorectal cancer progression and metastasis, such as PROCR, SCD, BMP4, CEACAM6, TESC, and TGFBI (Fig. 2A and Additional file 4: Table S3). This evidence concerns the gene BMP4 and colorectal cancer.