ESTABLISHMENT AND BEHAVIOR OF A TRANSPLANTED HUMAN PRIMARY GASTRIC CANCER IN NUDE MICE

A human primary gastric cancer tissue （adenocarcinoma Ⅱ—Ⅲ） was transplanted into nude mice （SWISS/DF, nu/nu）. It has been transfered for 8 generations at 56 sites in 28 nude mice with transplanting rate of 100%. The transplanted tumor is designated as transplanted human primary gastric cancer-1 in nude mice （THPGC-1）. The growth rate of THPGC-1 is rather rapid and the size of transplanted tumor reaches 1cm2 in 4—5 weeks after transfer. The morphology and histochemistry of the original tumor were retained well in the initial and serial transplanted tumors. THPGC-1 could secrete carcinoembryonic antigen （CEA）. After intravenous or intraperitoneal injection of 131Ⅰ-antiCEA monoclonal antibody into the THPGC-1 bearing nude mice, the radiolabeled antibody was concentrated and localized in the tumor as shown by γ-camera analysis. Similar pattern of lactate dehydrogenase isoenzyme was observed both in primary gastric cancer tissue and THPGC-1 tissue. Chromosomal examination revealed that THPGC-1 was human aneuploid ones. Southern blot analysis showed that the pattern of repetitive DNA bands and the structure of 28S rDNA, c-H-ras and c-myc genes in THPGC-1 were identical to the original primary gastric cancer DNA. The results suggest that THPGC-1 be a reliable model for the research of the molecular biology of cancer cells and experimantal gastric cancer diagnosis and treatment.