PROM1 and osteosarcoma: Experimental reprogramming of conventional osteosarcoma lines with the pluripotency factors OCT3/4, KLF4, and SOX2 confirms that these transcriptional circuits are sufficient to confer a CSC phenotype, characterised by up-regulation of CD24, CD26, and CD133, enhanced sphere formation, osteogenic capacity, migration, and broad chemoresistance [40].