CHROMATOGRAPHIC INVESTIGATIONS OF ESTRADIOL-RECEPTOR FROM BREAST-CANCER TISSUE

DEAE-cellulose chromatography of non-activated and activated estradiol receptors yields a different, characteristic elution pattern. This ch romatography should therefore be able to demonstrate the presence of i ntact receptors. For clinical receptor investigations, it is usual to select arbitrary cut-off values for receptor quantity and K-d to class ify into receptor positive and negative cases. DEAE-cellulose chromato graphy confirmed the results obtained by such classification in most c ases, except those which had been classified as negative on the basis of K-d values higher than 2 nM. In these cases, DEAE-cellulose chromat ography indicated the presence of estradiol receptors and therefore a misclassification of the measured results. Thus DEAE-cellulose chromat ography can contribute to a clarification of the equivocal results. On the other hand, we did not get any indications of damages to the rece ptor molecule which in our previous investigations were found to be th e result of violent homogenization procedures.