Soybean trypsin inhibitor was added to the primary cell culture for establishing a novel moderately differentiated human pancreatic adenocarcinoma cell line, PC-7. The PC-7 cell line was confirmed to be a malignant human pancreatic adenocarcinoma by morphological and biological studies. Chromosomal analysis and DNA content of PC-7 determined by flow cytometry showed a hypodiploid karyotypic pattern. Cultured PC-7 cells were inoculated into the back of athymic nude mice to create a transplanted tumor model. The effects of epidermal growth factor (EGF) and anti-EGF antiserum on PC-7 transplanted tumor were observed by injecting EGF or anti-EGF at the periphery of the solid tumors. In comparing to the control group, the tumor weights of the EGF group and the anti-EGF group were 138% and 67% respectively. Histological and electron microscopic studies higher mitotic rate in the EGF group and a lower rate in the anti-EGF group compared to the control. The results indicate that EGF stimulated and anti-EGF partially inhibited the growth of transplanted PC-7 solid tumors in athymic nude mice.