Tumor-bone interaction induced by transplantable human tumors in nude mice.

Tumor-bone interactions were experimentally studied using four transplantable human urogenital tumors in nude mice. The method consisted of subcutaneously (SC) inoculating tumor cells over the calvaria in nude mice after the periosteum has been disrupted. This resulted in a local tumor causing fragmentation of the bone. The degree of tumor-bone interaction also varied with the type of implanted tumors as shown in radiographic and histologic examinations. All tumors were associated with histologic patterns of classical bone remodeling, including bone destruction with osteoclast proliferation and reactive new bone formation. The evidence presented here suggests that the majority of tumor-bone interaction showed a combination of both features, bone destruction and new bone formation, and the mechanisms whereby tumors interact with bone may vary with the biological properties of the tumor. Our new system would be suitable for studying the biology of local interaction between bone and tumor cells and searching out a method to protect the bone from cancer cells.