[Effect of bortezomib combined with bisphosphonates on bone metabolism index in multiple myeloma]

This study was aimed to investigate the effect of bortezomib combined with bisphosphonates on serum levels of DKK-1 and RANKL in multiple myeloma patients, and to evaluate its role in the therapy of osteolytic lesion. Fourty-three patients with newly diagnosed and relapsed myeloma were divided into 2 groups. Twenty-three patients were treated with bortezomib combined with bisphosphonates (A group) and 20 patients were treated with bisphosphonates combined with traditional chemotherapy (B group). Serum levels of DKK-1 and RANKL were measured by ELISA before and after 4 cycles of chemotherapy. The results indicated that serum DKK-1 level significantly decreased in patients of A group (43.2 µg/L before vs 30.4 µg/L after 4 cycles of chemotherapy), and so did for serum RANKL level in A group (0.83 pmmol/L before vs 0.45 pmmol/L after 4 cycles of chemotherapy). While there was no significant differences in DKK-1 and RANKL serum level before therapy between A and B groups, but there was significant differences in DKK-1 and RANKL levels after 4 cycles of chemotherapy (P < 0.05). It is concluded that bortezomib combined with bisphosphonates obviously reduce the serum levels of DKK-1 and RANKL, thus has beneficial effect on osteolytic lesion.