For example, in multiple myeloma (MM) cells, CD40-induced Ku86 surface expression resulted in increased cellular adhesion to fibronectin and bone marrow stromal cells [12] Other reports indicate that Ku70/Ku86 is found in the cytoplasm during mitosis and it returns to the nucleus as the cell enters the G1 phase of the cell cycle [13,14]. The gene discussed is XRCC5; the disease is plasma cell myeloma.