Another crucial mediator of tumor angiogenesis and metastasis is the platelet-derived growth factor receptor (PDGFR); a positive correlation has been observed between levels of PDGFR-α expression and the aggressiveness of chondrosarcoma [13], so it is important to examine the molecular mechanisms underlying PDGF expression in human chondrosarcoma cells. The gene discussed is PDGFRA; the disease is chondrosarcoma.