In a nonhuman animal model that produces a secretory protein, which is obtained by transplanting secretory protein-expression vector-transfected cells into a nonhuman animal, an amount of the secretory protein is measured and, based on the amount of the secretory protein, transcriptional activity, number of the transplanted cells, and tumor volume is measured. Further, screening of a compound that affects a transcriptional activity, number of transplanted cells, or tumor volume is performed by using the nonhuman animal model to which a compound has been administered.