1981 Volume 72 Issue 12 Pages 1527-1533
The tumor line in nude mice is one of the most important experimental animal models on the oncodevelopmental study. We tried implantation of human testicular tumor into nude mice and could establish the AFP producing tumor line (JTG-1) and maintained it by the serial transplantation. The characteristics of this AFP producing tumor line (JTG-1) in nude mice from human testicular tumor are reported in this paper.
The nude mice, 4 to 8 weeks old male with BALB/c genetic back-ground were bred and maintained as specific pathogen free animals. The tumor blocks (5×5×3mm) from human testicular tumor were inoculated into mice's bilateral flanks. These animals were observed daily and the tumor size was measured once a week in two dimension (length and breadth). The serial AFP levels of the serum and the cystic fluids were determined every week for 8 weeks by the radioimmunoassay. The histological examination was performed in every tumor block of serial transplantation.
The tumor take was 100% and spontaneous regression could not be observed. The tumor growth was local and usually became cystic 3 weeks after inoculation. Thereafter the tumor growth was rapid and reached the maximum size of 8000mm2 (mean±SD: 4680±2630mm2) 8 weeks after inoculation on the 18th transplantation. The serum AFP levels increased from 10300±4500ng/ml 3 weeks to 42000±14800ng/ml 7 weeks after inoculation on the 18th transplantation and from 865±215ng/ml 3 weeks to 16500±2300ng/ml 7 weeks after inoculation on the 28th transplantation. The AFP levels of cystic fluids also showed a rapid increase from 95800±28700ng/ml 5 weeks to 345000±187000ng/ml 8 weeks after inoculation on the 18th transplantation and from 83700±42100ng/ml 5 weeks to 368900±112000ng/ml 8 weeks after inoculation on the 28th transplantation.
Histologically, the original tumor (human testicular tumor) was an embryonal carcinoma with seminoma and an endodermal sinus tumor pattern could not be observed. On the other hand the tumor inoculated into nude (JTG-1) was the yolk sac tumor, in which an endodermal sinus tumor pattern was dominant. From these results, we thought that the characteristics of the original tumor (human testicular tumor) changed to those of the yolk sac tumor histologically and biochemically after the first transplantation. But the characteristics of the tumor inoculated into nude mide did not change histologically and biochemically in the serial transplantation.
