Comparison of enzyme immunoassay and dextran-coated charcoal techniques for progesterone receptor determination in human breast cancer cytosols.
We have compared a new enzyme immunoassay for progesterone receptors (Abbott PgR-EIA, monoclonal) with our standard radioligand binding-assay (PgR-RBA). For both assays cytosols were freshly prepared from human breast cancer specimens that had been stored frozen for up to 1 year, and predominantly tissues were used which contained critically low amounts of progesterone receptors. A highly significant correlation was observed between the PgR-EIA and PgR-RBA (Spearman: Rs = 0.85, n = 100). Using a cut-off point of 10 fmol PgR/mg protein, 87% of the values were in accordance with each other (52% negative, and 35% positive in both assays), whereas 13% scored positive (median: 16, range 11-38 fmol PgR/mg protein) in one assay and negative (median: 7, range 0-10 fmol PgR/mg protein) in the other. Also in cytosols from human ovarian and endometrial carcinoma tissues immunoreactive PgR could be detected, and significant correlations with PgR-RBA were observed (Rs = 0.94, n = 6) for both tissues.
Foekens
J A
JA
Division of Endocrine Oncology, Biochemistry, Dr Daniel den Hoed Cancer Center, Rotterdam, The Netherlands.
Portengen
H
H
van Driel
J
J
van Putten
W L
WL
Haije
W G
WG
Klijn
J G
JG
D001943:Breast Neoplasms / Q000032:analysis*; D003600:Cytosol / Q000032:analysis; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D010051:Ovarian Neoplasms / Q000032:analysis; D011869:Radioligand Assay / Q000379:methods; D011980:Receptors, Progesterone / Q000032:analysis*; D014594:Uterine Neoplasms / Q000032:analysis
D011980:Receptors, Progesterone