Higher GPNMB concentration groups positively correlated with liver metastasis (P=0.040), while it is similar regarding to different T stage (P=0.230), N stage (P=0.134), M stage (P=0.595), brain metastasis (P=0.493) and bone metastasis (P=0.230) (Table 1). The gene discussed is GPNMB; the disease is bone metastasis.