SHMT2 and cancer: Under stress condition(s), phosphorylation of p62 activates NRF2 signaling by sequestering Keap1 (Kelch-like ECH-associated protein 1), leading to the upregulation of cytoprotective antioxidant genes including Serine Hydroxymethyltransferase 2 (SHMT2), hydroxyglutarate dehydrogenase(HGDH), and phosphohydroxythreonine aminotransferase 1 (PSAT1), thereby protecting cancer cells from oxidative stress [18].