GPT and osteosarcoma: Interestingly, in ΔT + shA + shD1 and ΔT + shA + shD2 cells, APBs were increased significantly, which were higher than the ΔT + shV cells and the ΔT + shA + shV cells, but still lower than human ALT osteosarcoma U2OS cells (Fig. 2A,B).