SOX2 and neoplasm: Furthermore, in surgically recovered tumor implants derived from TISCs expressing myc-TBC1D15, expression levels of the pluripotency markers OCT4, SOX2 and NANOG were increased elevated relative to those measured in tumors expressing non-targeting shRNAs, Flag-p53 or an shRNA to deplete TBC1D15 (Figures S6 and S7).