Measurement of c-erbB-2 proteins in sera from patients with carcinomas and in breast tumor tissue cytosols: correlation with serum tumor markers and membrane-bound oncoprotein.
Using a commercial kit with antibodies against the ectodomain of c-erbB-2 protein, we detected c-erbB-2 immunoreactivity in human serum. We found that the percentages of patients with elevated serum c-erbB-2 immunoreactivities were 35, 21, and 9% in breast, prostate, and ovarian carcinoma, respectively. The majority of the elevated immunoreactivities were associated with sera containing highly elevated tumor markers with the highest in breast carcinoma (35%) and lowest in ovarian cancer (9%). Excellent correlations were also observed between the serum levels of c-erbB-2 immunoreactivity and the dominant tumor markers in serial specimens from individual cancer patients. We could also detect the c-erbB-2 immunoreactivity in the cytosols prepared from the breast tumor tissue for estrogen and progesterone receptor (ER & PgR) measurements using the same commercial kit for serum studies, and the intact c-erbB-2 oncoprotein (p185) in the extracts of the tissue membrane fractions with a different kit designed for tissue extract. The level of c-erbB-2 immunoreactivity in the cytosol from 124 human breast tumor specimens had an excellent correlation with the cell membrane concentrations of p185 (gamma = 0.89). Most of the elevated cytosol c-erbB-2 immunoreactivities were also found to associate with breast tumor specimens containing low concentrations of ER & PgR. It appears that measuring the c-erbB-2 immunoreactivity potentially could be used as a prognostic marker without performing tissue biopsies and also as a serum tumor marker for managing cancer patients.
Wu
J T
JT
Department of Pathology, University of Utah Medical Center, Salt Lake City, USA.
Astill
M E
ME
Gagon
S D
SD
Bryson
L
L
D015415:Biomarkers; D014408:Biomarkers, Tumor / Q000097:blood*; D001943:Breast Neoplasms / Q000097:blood / Q000737:chemistry*; D018394:CA-125 Antigen / Q000097:blood; D018395:CA-19-9 Antigen / Q000097:blood; D002402:Cathepsin D / Q000032:analysis; D003600:Cytosol / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D008970:Molecular Weight; D018396:Mucin-1 / Q000097:blood; D015513:Oncogene Proteins / Q000032:analysis; D010051:Ovarian Neoplasms / Q000097:blood; D011237:Predictive Value of Tests; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood; D011480:Protease Inhibitors; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000097:blood* / Q000276:immunology / Q000648:ultrastructure; D011960:Receptors, Estrogen / Q000032:analysis; D011980:Receptors, Progesterone / Q000032:analysis
D015415:Biomarkers; D014408:Biomarkers, Tumor; D018394:CA-125 Antigen; D018395:CA-19-9 Antigen; D002402:Cathepsin D; D018396:Mucin-1; D015513:Oncogene Proteins; D017430:Prostate-Specific Antigen; D011480:Protease Inhibitors; D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone