As the top selected gene associated with the homing of the tumour cells in the bone environment, DDP9 (Dipeptidyl Peptidase 9) expression was highly positively with ITGA2 (Integrin Subunit Alpha 2) (r = 0.885, P < 0.05), CTGF (also called CCN2, Cellular Communication Network Factor 2) (r = 0.926, P < 0.05) and ITGB3 (Integrin Subunit Beta 3) (r = 0.917, P < 0.05). The gene discussed is ITGA2; the disease is neoplasm.