The proteins associated with the risk of multiple cancers included GDF15, a stress-regulated hormone that we found to be associated with an increased risk of eight cancers (liver, aerodigestive and gastrointestinal tract, and haematological malignancies), and MMP12, an enzyme expressed on macrophages that was associated with an increased risk of cancers of the colon, lung, and NHL15. Here, GDF15 is linked to malignant colon neoplasm.