PHGDH and breast cancer: Osteosarcoma cell lines (MG63, MNNG, NOS1, Saos2, and U2OS), human mesenchymal stem cells (the progenitor cell to bone-producing cells), and two breast cancer cell lines (MDA-MB-231 and MDA-MB-468) with known PHGDH status (null and high, respectively) were selected for further in vitro analysis of PHGDH biology (Pacold et al., 2016).