A2M and osteosarcoma: In addition, it was noticed that seven genes (VAMP8, A2M, HLA-DRA, SPARCL1, HLA-DQA1, APOC1 and AQP1) were continuous upregulating during the oncogenesis and metastasis of osteosarcoma, which suggested that these genes may act as oncogenes and be consistently involved in the pathophysiological process of osteosarcoma.