[Establishing orthotopic transplanted models of human pancreatic cancer in nude mice and study on their biological properties].

Two cell lines of human pancreatic cancer have been established, which can be successfully transplanted into pancreas of nude mice, the first of this kind of cell lines in China. Fresh specimens human of pancreatic cancer taken surgically were transplanted in the pancreas of pure line BALB/C-nu/nu nude mice. The transplanted tumours grew and reproduced successfully, and were named PINMP-1 and PINMP-2, respectively. So far, 9 generations of PINMP-1 and 6 generations of PINMP-2 were obtained. Their biological properties, ways of invasion and metastasis and morphological characteristics under light and electron microscope were studied. The results showed a 95%-100% transplanting success rate, with the success rate of transplanting from tissues revivified from the liquid nitrogen preservation being 100%. Both of the lines could produce large amount of CEA, and chromosome analysis confirmed that they had retained a karyotype of the human cancer cells. In nude mice transplanted with the tumours, metastasis could be found in the lymph nodes, lungs and livers. Metastasis via lymphatic channels and blood vessels were also demonstrated. The pathological and ultrastructural examination confirmed that the transplanted tumours had identical characteristics as their donor tumours. The transplanted cells grew independently in the pancreas of the nude mice, making a better model for study on tumour invasion and metastasis than subcutaneously transplanted tumours. This indicated that the microenvironment in the transplantation site had certain influence on the biological behavior of the transplanted tumours. The models could be used in the study on the invasion, metastasis and experimental therapy of pancreatic carcinomas.