SOX2 and metastasis: For instance, ALDH1A3 expression in T-47D cells growing in PDSs was associated with the presence of lymph node metastasis [42], and the prevalence of high expression of the pluripotency markers SOX2 and NANOG in MCF7 cells cultured in PDSs was linked to the absence of the ERα in the original tumor and low DSF, respectively, in agreement with previous observations in tumor tissue [46,47].