Human Tumor Xenograft Models in NCI Drug Development

Abstract

The methods used by the National Cancer Institute (NCI) for in vivo preclinical development of anticancer drugs were described in detail in the first edition of this book (1). In addition, a series of review articles have charted the evolution of the overall NCI drug discovery process, which began in 1955 (2--12). Although the methodologies associated with xenograft model testing have remained fundamentally the same, during the past 10 yr a series of improvements to preclinical drug testing to expedite in vivo drug development have been made that now precede the employment of xenograft models in the in vivo drug development process. These specialized assays are described in Chapter 8. For the sake of completeness, the present chapter provides (1) a brief history of the in vivo screens used by the NCI, (2) a description of the human tumor xenograft systems that are employed in preclinical drug development, and (3) a discussion of how these xenograft models are employed for both initial efficacy testing as well as detailed drug evaluations.