Validation of a multiplex immunoassay for serum angiogenic factors as biomarkers for aggressive prostate cancer.
BACKGROUND
Assays used for discovery of biomarkers should be robust and high-throughput, capable of analyzing a sufficiently large number of samples over a sufficiently long period of time with good precision.


METHODS
We evaluated the analytical performance of the Bio-Plex Pro™ Human Cancer Biomarker Panel 1, a 16-plex multiplex immunoassay, in serum for composite profiling of angiogenic factors. Because prostate cancer progression and metastasis are pathological events closely linked to angiogenesis, serum angiogenic factors are ideal candidates as prognostic biomarkers.


RESULTS
Our 5-day evaluation indicated that all 16 assays in the panel had good reproducibility (total precisions over 5 independent plates in 5 days of <20%), adequate sensitivity (LOQs of majority of the assays less than 100 pg/ml), and wide dynamic ranges (linearity of majority of the assays spanning across 3 logs in concentrations).


CONCLUSIONS
Applying the panel to sera from prostate cancer patients with Gleason scores of 6, 7, 8-10, tumor stages that correlated with clinical outcome, we identified that the levels of sTIE-2, a soluble form of the transmembrane tyrosine kinase receptor for angiopoietins, were increased in patients with Gleason score of 8-10. Future studies are necessary to determine whether sTIE-2 could be used as a prognostic biomarker for identifying aggressive prostate cancer.
Department of Pathology, Johns Hopkins University, Baltimore, MD 21287, USA. dli@jhu.edu
Danni
D
Li
Hanching
H
Chiu
Vinita
V
Gupta
Daniel W
DW
Chan
D014408:Biomarkers, Tumor / Q000097:blood*; D006801:Humans; D007118:Immunoassay / Q000592:standards*; D008297:Male; D060787:Neoplasm Grading; D009389:Neovascularization, Pathologic; D011379:Prognosis; D011471:Prostatic Neoplasms / Q000097:blood* / Q000098:blood supply* / Q000175:diagnosis; D042787:Receptor, TIE-2 / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D014408:Biomarkers, Tumor; D042787:Receptor, TIE-2