[Effect of 2 phosphonates on the osteolysis induced by tumor extracts]

An in-vitro model is proposed to test the potential effect of diphosphonates in treatment or preventing bone metastases. This model involves culturing of neonatal mice calvaria in sterile conditions in an appropriate medium and measuring 45Ca release from bone to medium, the mice being injected with 45Ca on the day of birth. Tumour extracts added to the medium usually increase the bone lysis; this effect is significantly decreased when the mice have been treated with either ethane-hydroxy-diphosphonate (EHDP) or dichloromethylene-diphosphonate (Cl2MDP). These experiments represent a first step in a group of experiments with a view to clinical trials in cases of bone metastases.