SHMT1 and neoplasm: These data are in agreement with the analysis of GSE29827 data set (LUAD with metastasis vs. LUSC with metastasis), showing that shmt1 is highly upregulated in metastatic LUAD only (Fig. 4B), in agreement with our working hypothesis that the cytosolic isoform of SHMT may play an essential and unique role in the metastatic potential of this type of tumor.