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A Magnetic Bead-Based Sensor for the Quantification of Multiple Prostate Cancer Biomarkers.

Jokerst JV, Chen Z, Xu L, Nolley R, Chang E, Mitchell B, Brooks JD, Gambhir SS - PLoS ONE (2015)

Bottom Line: The results were analyzed with receiver operator characteristic curve analysis.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).This bead-based system offers important advantages in assay building including low cost, high throughput, and rapid identification of an optimal matched antibody pair.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Molecular Imaging Program at Stanford (MIPS), Stanford University, Stanford, California, United States of America.

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.

No MeSH data available.


Related in: MedlinePlus

Serum Validation.A) Percent recovery for three representative biomarkers. Matrix effects can either dampen signal (CA1, PAP) or inflate signal (SPARC). Ideal dilution factors were dependent on sensitivity of the assay and reference range of the biomarker (Table 1). Black dashed line indicates 100% spike recovery. B) Bland-Altman plot [38] validating specimen integrity of a subset (N = 35) of the clinical samples with high sample volumes. Red dashed line indicates 95% confidence interval.
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pone.0139484.g003: Serum Validation.A) Percent recovery for three representative biomarkers. Matrix effects can either dampen signal (CA1, PAP) or inflate signal (SPARC). Ideal dilution factors were dependent on sensitivity of the assay and reference range of the biomarker (Table 1). Black dashed line indicates 100% spike recovery. B) Bland-Altman plot [38] validating specimen integrity of a subset (N = 35) of the clinical samples with high sample volumes. Red dashed line indicates 95% confidence interval.

Mentions: With an optimized matched antibody pair in hand, we next uncovered and corrected any matrix interferences again illustrating with PAP. We used pooled normal female serum that should contain no PAP. Serum at dilution factors from 1:2–1:256 was prepared and analyzed. Another batch of diluted samples was spiked with 0.5 ng/mL PAP. The samples were analyzed and the percent recovery plotted in Fig 3A as well as spike recovery data for SPARC spiking at 125 ng/mL and CA1 spiking at 10 ng/mL. The results showed that 100% recovery was achieved with 16-fold dilution factors for these analytes. Decreased and increased spike recovery values are due to non-specific binding of other serum proteins to the antibodies. The other five biomarkers were optimized similarly.


A Magnetic Bead-Based Sensor for the Quantification of Multiple Prostate Cancer Biomarkers.

Jokerst JV, Chen Z, Xu L, Nolley R, Chang E, Mitchell B, Brooks JD, Gambhir SS - PLoS ONE (2015)

Serum Validation.A) Percent recovery for three representative biomarkers. Matrix effects can either dampen signal (CA1, PAP) or inflate signal (SPARC). Ideal dilution factors were dependent on sensitivity of the assay and reference range of the biomarker (Table 1). Black dashed line indicates 100% spike recovery. B) Bland-Altman plot [38] validating specimen integrity of a subset (N = 35) of the clinical samples with high sample volumes. Red dashed line indicates 95% confidence interval.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4589536&req=5

pone.0139484.g003: Serum Validation.A) Percent recovery for three representative biomarkers. Matrix effects can either dampen signal (CA1, PAP) or inflate signal (SPARC). Ideal dilution factors were dependent on sensitivity of the assay and reference range of the biomarker (Table 1). Black dashed line indicates 100% spike recovery. B) Bland-Altman plot [38] validating specimen integrity of a subset (N = 35) of the clinical samples with high sample volumes. Red dashed line indicates 95% confidence interval.
Mentions: With an optimized matched antibody pair in hand, we next uncovered and corrected any matrix interferences again illustrating with PAP. We used pooled normal female serum that should contain no PAP. Serum at dilution factors from 1:2–1:256 was prepared and analyzed. Another batch of diluted samples was spiked with 0.5 ng/mL PAP. The samples were analyzed and the percent recovery plotted in Fig 3A as well as spike recovery data for SPARC spiking at 125 ng/mL and CA1 spiking at 10 ng/mL. The results showed that 100% recovery was achieved with 16-fold dilution factors for these analytes. Decreased and increased spike recovery values are due to non-specific binding of other serum proteins to the antibodies. The other five biomarkers were optimized similarly.

Bottom Line: The results were analyzed with receiver operator characteristic curve analysis.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).This bead-based system offers important advantages in assay building including low cost, high throughput, and rapid identification of an optimal matched antibody pair.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Molecular Imaging Program at Stanford (MIPS), Stanford University, Stanford, California, United States of America.

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.

No MeSH data available.


Related in: MedlinePlus