It was reported that the mitochondrial isoform of SHMT in one-carbon metabolism, SHMT2, is upregulated in Myc-overexpressing neuroblastoma and GBM cell lines, but not other cancer cell lines (SH-SY5Y, HEK293T, H1299, and HT1080) upon hypoxia [52]. Here, SHMT2 is linked to cancer.