Herein we report that CR, relative to a high calorie control diet regimen, significantly reduces body weight and body fat, modulates the nutrient-responsive serum growth factor IGF-1, decreases growth of transplanted Panc02 and MiaPaCa-2 pancreatic cancer cells in male mice, and modulates protumorigenic gene expression in Panc02 and MiaPaCa-2 tumor pancreatic tumor cells. The gene discussed is IGF1; the disease is neoplasm.