Human Tumor Xenografts and Explants

Abstract

Since the first report of the successful xenografting of a human tumor into nude mince in 1969, there have been numerous studies conducted throughout the world using the nude mouse as a tool to answer a variety of questions regarding the cause, prevention, and therapy of caner. Thus, the role of immunodeficient animals in oncology has continuously increased, and the athymic nude mouse has provent to be an outstanding host for many human solid-tumor xenografts (1,2). These mice are now extensively used in the development of potential anticancer drugs, new antineoplastic treatment modalties, and studies of tumor biology (3-7). Moreover, mice with severe combined immunodeficiency (SCID) have enlarged the spectrum of possible applications in cancer research and enabled engraftments of human tumors that were previously difficult to explant, such as those of the hematopoietic system (8). Prior to the discovery of immunodeficient mice, syngeneic transplantable mouse tumor systems or autochtonous rat tumors were employed as the main - or the only-tools in the development of antitumor agents (5,7,9). Most of the chemotherapeutic agents currently used in the clinic have been developed in these rodent tumor models (reviewed in chapters 1-4). The most frequently used murine tumors were the leukemias L1210 and P388, the melanoma B16, and the Lewis Lung cancer (LLC) model. Yet the classes of agents found active in the mouse tumor models, however, were limited, and mainly comprise alkylating agents, and some other DNA interacting drugs (5,10,11).