Influence of treatment with APD-bisphosphonate on the bone lesions in the mouse 5T2 multiple myeloma.

The effects of the treatment of multiple myeloma (MM) with APD-bisphosphonate on bone destruction, the dissemination pattern of the MM, and toxicity for normal and malignant cells were investigated in an animal model, the 5T2 MM. This mouse MM very closely resembles the human disease, including the typical bone lesions. It was demonstrated by radiography, microradiography, and histologic investigation that the treatment of the 5T2 MM with APD-bisphosphonate protected the mice against a loss of bone to a significant extent. It seemed that the treatment with APD not only diminished the bone destruction by the MM but also led to the formation of new bone in already-affected bone tissue. The growth pattern of the MM was not substantially influenced by the treatment, even though there was an indication that APD exerts some cytotoxic effect on the MM cells.