Next, we assessed HACE1 transcript levels in two other osteoblast cell lines, OBB and hFOB43, and different osteosarcoma cell lines using quantitative reverse transcriptase polymerase chain reaction (RT-PCR), revealing significantly higher HACE1 expression in osteoblasts compared to osteosarcoma cell lines (p < 0.001) (Fig. 1g). The gene discussed is HACE1; the disease is osteosarcoma.