SHMT2 and head and neck cancer: Recent research has shown that initiation of the NRF2/Keap1 signaling pathway protects head and neck cancer cell lines from cisplatin and artesunate-induced oxidative stress and apoptosis by positively controlling the levels of expression of the essential serine/glycine biosynthesis enzymes PHGDH, PSAT1, and SHMT2, whereas inhibition of this pathway reverses resistance to ferroptosis and enhances drug sensitivity [54].