To examine the role of P-selectin and PSGL-1 interaction on extravasation and homing of MM cancer cells to the BM in vivo, we injected MM cells labeled with calcein-AM and detected the number of calcein-AM-positive cells both in the blood and the BM samples 50 minutes after injection, indicating extravasation and homing, respectively. The gene discussed is SELP; the disease is Miyoshi myopathy.