Sometimes referred to as a reagent, Ab is necessary for a wide range of diagnostic, clinical and experimental procedures. In the late 1980s the methodology for engineering transgenic mice made it possible to create mice to address specific questions and problems. The genetic alteration affects the germ plasm, and subsequently can be transmitted to progeny. Through selective breeding, it then is possible to maintain a strain of mice consisting of individuals with particular traits of interest. A specific trait, such as a predisposition to develop a particular type of tumor, can be introduced into a mouse strain by injecting into the embryo an oncogene, a gene that causes cancer.
Transgenic mice permit the study of cancer in specific tissues, including initial tumor development.
The purpose of cancer research is to understand tumor initiation and growth. This information helps researchers develop treatments, and eventually cures, for cancer. Specific tumors from humans are transplanted into nude and SCID mice. Mice with tumors are treated with different compounds to see if their tumors regress. Cancer cells from humans are also cultured in vitro to screen possible useful compounds.