ANDROGEN RECEPTOR ASSAYS IN SPECIMENS OF PROSTATIC TISSUE OBTAINED BY TRANSURETHRAL RESECTION AND TRANSVESICAL ADENOMECTOMY

The main goal of this study was to ascertain whether routine transurethral resection (TUR) of prostate may provide useful material for the evaluation of androgen receptor (AR) status. At the same time, either intracellular distribution of binding affinity and capacity of receptor molecules were particularly taken into account. Based on our previous findings in breast and endometrial cancer, we suggest that a "functional" receptor status may correspond to the presence of type I (high affinity, low capacity) AR in both soluble and nuclear fractions. However, the precise significance of type II (lower affinity, higher capacity) binding sites remains to be clarified. Ten samples of large prostatic adenomas, obtained by transvesical adenomectomy (TVA), were compared with ten parallel specimens obtained by an in vitro TUR, whereby a pure cutting current was used. The AR assay was carried out with a standard competition method using tritiated mibolerone as the radioligand and Scatchard analysis for data processing. No significant difference between the TUR and TVA groups emerged concerning type I AR content of soluble, nuclear or soluble together with nuclear fractions; this was also true when the results were expressed either as fmol/ml homogenate or as fmol/mg DNA. Similarly, concentrations of type II AR in TVA and TUR samples did not differ significantly in either cell compartment, although they were widely scattered, especially in the soluble fraction. In the light of our findings, it is suggested that TUR specimens represent suitable material for receptor studies, provided that only cutting current is employed and that the use of coagulation current, to control bleeding from the prostatic bed, is confined to the final step of the TUR procedure.