At the protein level, NFS1 was notably increased in representative CRC tissues (Fig. 7d), in primary ESCC and CRC tissues compared with adjacent normal tissues, and even at different CRC phases based on tumor tissue microarrays (Fig. 7e, f and Supplementary Fig. S6d, e) (clinicopathological information is provided in Supplementary Table S1). Here, NFS1 is linked to esophageal squamous cell carcinoma.