A regulation of PHGDH and SHMT2 by the transcription factor Nrf2 has recently been reported in non-small cell lung cancer cells.17 Similarly, we found an induction of PHGDH and SHMT2 but not SHMT1 by the Nrf2 activator RA 839 in LNT-229 and G55 cells (Suppl. This evidence concerns the gene SHMT1 and non-small cell lung carcinoma.