A sensitive and specific non-invasive urine biomarker panel for prostate cancer detection.

Background: Prostate cancer (PCa) is one of the leading causes of cancer death in men. While prostate-specific antigen (PSA) testing is widely used for screening, its diagnostic accuracy is limited, often failing to distinguish between benign and malignant prostate conditions, underscoring the need for novel biomarkers with improved diagnostic performance. This study aimed to identify and validate a panel of urinary RNA biomarkers with improved diagnostic accuracy for PCa.

Methods: RNA-sequencing analysis of exfoliated cells in urine specimens identified 50 candidate RNAs. After initial qPCR testing in pooled urine, three biomarkers (TTC3, H4C5, EPCAM) with optimal specificity and sensitivity were selected as a biomarker panel. Diagnostic performance was evaluated in a case-control study divided into development (n = 243 participants) and validation (n = 646 participants) datasets. Biomarker expression was confirmed in tissue specimens, and the oncogenic function of TTC3 was assessed in vitro and in vivo.

Findings: The three-biomarker urine panel robustly identified PCa with an area under the curve (AUC) of 0.96 (95% CI: 0.94-0.98) compared to 0.83 (95% CI: 0.77-0.88) for urinary prostate cancer antigen 3 (PCA3) RNA in the development dataset and 0.92 (95% CI: 0.89-0.94) compared to 0.76 (95% CI: 0.72-0.80) for PCA3 in the validation dataset. Urine biomarkers were nearly eliminated post-prostatectomy and were confirmed to originate from prostate tissue at both the RNA and protein levels. The panel maintained high diagnostic accuracy of PSA-negative PCa cases and distinguished PCa from benign prostate conditions (BPH, prostatitis). Functional studies demonstrated that TTC3 depletion significantly suppressed in vitro and in vivo tumour growth.

Interpretation: This urine-based biomarker panel offers a promising sensitive and specific noninvasive diagnostic for PCa with the potential to form the basis for laboratory-developed and in vitro diagnostic assays.

Funding: This study was supported by the International Prostate Cancer Foundation, JHU SKCCC (grant number P30CA006973), and Bankhead-Coley Cancer Research Program (grant number 24B16) to R. J. Perera and by the Maryland Innovation Initiative Grant to C. P. Pavlovich and R. J. Perera.