Bone is the most common target organ of breast cancer metastasis. At present, accumulating evidence suggests that inhibition of the receptor activator of nuclear factor-kappa B ligand (RANKL) does not only induce an increase in bone mass and strength ...
Bone is the most common target organ of breast cancer metastasis. At present, accumulating evidence suggests that inhibition of the receptor activator of nuclear factor-kappa B ligand (RANKL) does not only induce an increase in bone mass and strength but also has anti-tumor effects. Here, I proposed a strategy using mutated RANKL (RANKLM) as an immunogen for active immunization to induce anti-cytokine antibodies for the immune therapy of bone metastatic cancer. I then investigated whether the produced RANKL antibody could inhibit osteolytic bone metastasis of breast cancer in a murine model. The reduced intraosseous growth of MDA-MB-231 cells in vivo, as a result of RANKLM treatment, was correlated with decreased osteolytic lesions and hindered tumor progression. In addition, RANKLM treatment led to significant improvements in overall survival and in the skeletal metastasis of tumor-bearing mice. I confirmed inhibition of osteoclast activities in xenograft models injected with a recombinant mutant RANKL, demonstrating that RANKLM immunization inhibits osteolytic bone metastasis in breast cancer. This study suggests that vaccination with an inactive recombinant mutant RANKL could be investigated for its ability to prevent bone metastasis of breast cancer.