Consistent with the correlation pattern between MDH2 and metabolites, the results demonstrated that DEGs (FLT1, VCAN, PTGS1, IL13RA2, MMP3, and SYK) associated with promoting breast cancer metastasis were positively correlated with 23 different metabolites and negatively correlated with 39 different metabolites (Fig. 9b). This evidence concerns the gene PTGS1 and breast cancer.