前立腺腫瘍の実験的研究 III:下垂体・副腎皮質ホルモンの影響

Abstract

As similar procedures as described in the Part II, eff e cts of various pituitary and adrenocortical hormones on the development of experimental prostatic tumors produced by intraprostatic injection of 0.1cc of 3% 20-MCT in Tween 80 were observed on the characteristics of the tumors after 6 months of injection. 1) ACTH administration. The initial o ccurrence of the tumor was seen in 120 days and the incidence was recorded as 55% (11 out of 20 animals) after 6 months and as 52.1% throughout the observation. The results indicate presence of a slight suppressing effect of ACTH on the tumor development, but the tumor was found to be relatively large, being the mean weight of 1.589 gms. 2) HCG administration. A slightly high rate of occurrence of tumor, 64.2%, was demonstrated throughout the observation, but the rate after 6 months was only 56.4% (9 out of 16) and the weight of the tumor developed was only 0.227 gms as the mean, which is indicating relatively mild effect of the hormone on tumor acceleration. 3) Prolactin administrat ion. A relatively e a rly initiation in development of tumor, 100 days, as squamous epitheliar type, was seen. However the incidences after 6 months and throughout the observation were 62.5% (10 out of 16) and 60% respectively, which is not particularly different from that of in the group given 20-MCT alone. 4) Cortisone administra t ion The incidences of the tumor throughout the observation and after 6 months were 64.0% and 68.4% (13 out of 19) respectively, which are the highest values in the all experimental groups. The tumor developed weighed 2.424 gms as the mean, which is heavier than the other groups. The results indicate marked accelerated and proliferative effects of cortisone. 5) Metopiron administration. The incidences were slightly lower than that of in the cortisone treated group and were 52.7% (10 out of 19) after 6 months and 52% throughout the observation. The mean we ight of the tumor was 2.049 gms. It is supposed that the hormone has minimal suppressing effect. Summarizing these results, it is postulated that the development of prostatic tumor s h ows a closed correlation to the pituitary and adrenocortical glands even though it is not so strikingly as sexual hormones. It should be mentioned that for development of prostatic tumors, which are believed to be depend upon male sexual hormones, not only the gonadotropic hormones but also the adrenocortical disfunctions or subsequent changes of the pituitary functions might be emphasized as important factors, although the physico-chemical characteristics of hormones, correlation between the hormones and the carcinogenic agents, genetic factors of the experimental animals and many other factors must be considered.