Tumor cachexia and hypercalcemia in nude rats and mice bearing human renal carcinomas

Human hypercalcemia-inducing renal tumors have been established as xenografts in nude mice and nude rats. Animals bearing these tumors became cachexic and hypercalcemic and these changes could be reversed by excision of xenograft tumors. Metabolic studies carried out in nude rats suggested that the hypercalcemia-inducing factor was effecting renal excretion of calcium but was probably not parathyroid hormone. Although the hypercalcemia-inducing property of the tumor was stable throughout serial transplantation of tumor from animal to animal, it was lost after passage through cells in culture.