Abstract: The invention relates to a method for inducing bone formation via administration of an extract of devitalized, freeze dried Saos-2 cells. The extract is prepared by contacting the freeze dried Saos-2 cells, which are devitalized in the act of freeze drying, with a weak denaturing agent of the type used to separate proteins from cells. It is not clear that the active ingredient in the extract is a protein; however, the extract does have properties superior to comparable treatment using whole Saos-2 cells. Also, described are the extracts themselves and various compositions containing it.