LEF1 and osteosarcoma: Regarding as the canonical Wnt signaling activity in osteosarcoma, some osteosarcoma cell lines were found to have relatively increased β-catenin transcriptional activity relative to human MSCs, and increased expression of β-catenin and LEF1 mRNA in human osteosarcoma compared to human fetal osteoblasts, paired with increased active β-catenin protein by western blot [22, 30].