Androgen receptors in rectal and colonic cancer.
To evaluate the potential effect of androgens on human colorectal cancer, the prevalence and concentration of cytosolic androgen receptors were analyzed in 23 rectal and 13 cecal adenocarcinomas by a hybrid radioligand assay. Androgen receptors were detected in nine of the rectal (39 percent) and five of the cecal tumors (38 percent). Androgen receptor levels demonstrated were low, ranging from three to 17 fmol/mg cytosol protein. Dissociation constants were 1 nM or less. The presence of androgen receptors was independent of age or sex of the patient, and of the state of histologic differentiation and Dukes' staging of the tumor. Androgen receptor prevalence was similar in mucosa adjacent to rectal and cecal adenocarcinomas and in mucosa from five of ten patients (50 percent) with diverticular disease. Our findings suggest that androgen dependency does not play a major role in endocrine control of the development of rectal cancer.