Trigonelline is one of the most elevated metabolites in the livers of sham-operated Nnmt knockout mice (Supplementary Fig. 5a, b), suggesting that the yet-to-be-identified trigonelline biogenesis pathway consumed SAM in the absence of Nnmt. In the WT livers of 4T1 breast cancer-bearing mice, not only MNAM but also trigonelline was elevated (Supplementary Fig. 5a, b). This evidence concerns the gene NNMT and breast cancer.