Analysis of Androgen-and Progestin Receptors in Human Endometrial Carcinomas

Androgen-binding components labeled with a tritiated synthetic androgen, methyltrienolone(R1881) were analysed in human endometrial carcinoma cytosols. Tritiated R1881 binding consists of 3 components; high-affinity, low capacity androgen binding (androgen receptor), possible progestin receptor and non-specific androgen binding. The existence of androgen receptor in the tumor suggests a direct effect of androgen in endometrial carcinoma, possibly, through its interaction with the androgen receptor. Androgen- and progestin receptors were further measured in the cytosols of 20 endometrial carcinomas from 19 non-treated patients. The concentrations of the androgen receptors in the endometrial carcinomas were, in decreasing order; highly differentiated [21.5 + 5.4(SEM) fmoles/mg protein, N=10], moderately differentiated [3.4 + 2.7, N=3] and poorly differentiated tumors [2.5 + 1.4, N=7]. The concentrations of progestin receptors in the highly differentiated, moderately differentiated and poorly differentiated tumors were 291 + 79.7 (N=10), 52.6 + 34.1(3) and 14.7 + 6.8(7), respectively. Androgen- and progestin receptors in endometrial carcinomas would appear to correlate with histologic grade of differentiation of the tumor.