title: A Magnetic Bead-Based Sensor for the Quantification of Multiple Prostate Cancer Biomarkers.
abstract: Novel biomarker assays and upgraded analytical tools are urgently needed to accurately discriminate benign prostatic hypertrophy (BPH) from prostate cancer (CaP). To address this unmet clinical need, we report a piezeoelectric/magnetic bead-based assay to quantitate prostate specific antigen (PSA; free and total), prostatic acid phosphatase, carbonic anhydrase 1 (CA1), osteonectin, IL-6 soluble receptor (IL-6sr), and spondin-2. We used the sensor to measure these seven proteins in serum samples from 120 benign prostate hypertrophy patients and 100 Gleason score 6 and 7 CaP using serum samples previously collected and banked. The results were analyzed with receiver operator characteristic curve analysis. There were significant differences between BPH and CaP patients in the PSA, CA1, and spondin-2 assays. The highest AUC discrimination was achieved with a spondin-2 OR free/total PSA operation--the area under the curve was 0.84 with a p value below 10(-6). Some of these data seem to contradict previous reports and highlight the importance of sample selection and proper assay building in the development of biomarker measurement schemes. This bead-based system offers important advantages in assay building including low cost, high throughput, and rapid identification of an optimal matched antibody pair.
authors.affiliation: Department of Radiology, Molecular Imaging Program at Stanford (MIPS), Stanford University, Stanford, California, United States of America.
authors.forename: Jesse V
authors.initials: JV
authors.lastname: Jokerst
authors.affiliation: Department of Urology, Stanford University, Stanford, California, United States of America.
authors.forename: Zuxiong
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Department of Radiology, Molecular Imaging Program at Stanford (MIPS), Stanford University, Stanford, California, United States of America.
authors.forename: Lingyun
authors.initials: L
authors.lastname: Xu
authors.affiliation: Department of Urology, Stanford University, Stanford, California, United States of America.
authors.forename: Rosalie
authors.initials: R
authors.lastname: Nolley
authors.affiliation: Department of Radiology, Molecular Imaging Program at Stanford (MIPS), Stanford University, Stanford, California, United States of America.
authors.forename: Edwin
authors.initials: E
authors.lastname: Chang
authors.affiliation: Department of Radiology, Molecular Imaging Program at Stanford (MIPS), Stanford University, Stanford, California, United States of America.
authors.forename: Breeana
authors.initials: B
authors.lastname: Mitchell
authors.affiliation: Department of Urology, Stanford University, Stanford, California, United States of America.
authors.forename: James D
authors.initials: JD
authors.lastname: Brooks
authors.affiliation: Department of Radiology, Molecular Imaging Program at Stanford (MIPS), Stanford University, Stanford, California, United States of America; Bioengineering, Materials Science & Engineering, Bio-X, Stanford University, Stanford, California, United States of America.
authors.forename: Sanjiv S
authors.initials: SS
authors.lastname: Gambhir
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D058185:Magnetite Nanoparticles; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D011379:Prognosis; D011470:Prostatic Hyperplasia / Q000175:diagnosis*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000628:therapy
chemical_list: D014408:Biomarkers, Tumor; D058185:Magnetite Nanoparticles