Urinary PCA3 detection in prostate cancer by magnetic nanoparticles coupled with colorimetric enzyme-linked oligonucleotide assay

PCA3 is one of the most prostate cancer-specific genes described to date. Of note, PCA3 expression is detectable at high level in the urine of prostate cancer (PCa) patients. Accordingly, PCA3 is an ideal biomarker for PCa diagnosis. Several techniques for the measurement of this biomarker in urine have been developed but there are still some drawbacks. In this study, magnetic nanoparticle-based PCR coupled with streptavidin-horseradish peroxidase and a substrate for colorimetric detection was established as a potential assay for urinary PCA3 detection. The method provided a high specificity for PCA3 gene in LNCaP prostate cancer cell line. Additionally, this technique could detect PCA3 at femtogram level which was approximately 1,000-fold more sensitive than the conventional RT-PCR followed by agarose gel electrophoresis. The effectiveness of the method was assessed by PCA3 detection in clinical specimens. The relative PCA3 expression of PCa patients determined by this assay was significantly greater than that of benign prostatic hyperplasia (BPH) patients and healthy controls. The results of our test were comparable with the results of qRT-PCR. The proposed method is promising to distinguish between cancerous and non-cancerous groups. Altogether, this simple assay is practicable and useful for prostate cancer diagnosis.