ABSTRACT
The growth of several tumor types including breast, prostate, and endometrial cancer is, to some degree, under hormonal control. The nude mouse has provided a useful system in which to study the in vivo synthesis, secretion, and excretion of tumor markers. The malignant nature of oncogenic transformation has primarily been demonstrated by the in vitro focus induction assay, but in many cases has also been verified by the use of the nude mouse. Alpha-Fetoprotein (AFP) is a serum protein produced by the fetal liver and yolk sac during prenatal development and is often found in the corresponding tumors. Heterogeneity of metastatic ability within a human tumor cell population has been demonstrated by isolating subpopulations of cells with increased metastatic potential. Nude mice have proven invaluable as a research tool to aid the study of the in vivo biology of human tumors.
