Inhibition of GSK-3 activity with lithium chloride, SB216763, inhibitor IX (BIO) or with siRNA specific for GSK-3β resulted in suppression of GSK-3β and NF-κB activities and cellular proliferation and induction of apoptosis in human osteosarcoma cells in vitro and in mouse xenograft studies. This evidence concerns the gene GSK3B and osteosarcoma.