CHA59, Saos-2, and HuO9 were immunoprobed for the expression of cell surface markers (CD133, CD24, CD166, CD326, CD44, ABCB1, ABCC1, ABCG2) previously reported to be associated with TSCs and/or osteosarcoma [3], [17], [27]. This evidence concerns the gene CD44 and osteosarcoma.