Growth of a plasma cell myeloma in lathyritic mice.

Growth of a plasma cell myeloma (Adj PC-5) was studied in mice made lathyritic by the administration of beta-amino-proprionitrile (BAPN). The number of bones that had their medually cavities filled with tumor cells was notably decreased compared with tumor-bearing mice not treated with BAPN. Other aspects of tumor growth were the same. BAPN caused some retardation of tumor growth in the medullary cavity, but also caused osteoporosis and decreased tensile strength of collagen that allowed expansion of tumor growth outside the bones to proceed as usual. Additionally, the tumor-bearing mice showed some inhibition in their response to BAPN. This agrees with previous work that has shown that the response to BAPN treatment is greatest in animals that otherwise are healthiest.