Furthermore, knockdown of BMP4 by siRNAs markedly retarded DJ-1-induced CRC cell migration and invasion (Fig. 5c–e and Supplementary Fig. 6C), while BMP4 overexpression restored CRC cell migration and invasion inhibited by DJ-1 shRNA (Fig. 5f–h and Supplementary Fig. 6D). Here, BMP4 is linked to colorectal carcinoma.