RNA Biomarkers as a Response Measure for Survival in Patients with Metastatic Castration-Resistant Prostate Cancer

Area of Science:

• Oncology
• Molecular Biology
• Biomarker Discovery

Background:

• Prognosticating outcomes in metastatic castration-resistant prostate cancer (mCRPC) is complex.
• A need exists for early biomarkers to differentiate short-term from long-term survivors after treatment initiation.

Purpose of the Study:

• To investigate the predictive value of early RNA biomarkers for progression-free survival (PFS) and overall survival (OS) in mCRPC.
• To determine if RNA biomarkers improve existing clinical prediction models.

Main Methods:

• Measured RNA biomarkers (KLK3 mRNA, miR-375, miR-3687, NAALADL2-AS2) in 93 mCRPC patients before and 1 month after initiating abiraterone acetate or enzalutamide.
• Utilized Harrell's C-index to assess biomarker added value to standard clinical parameters for predicting PFS and OS.
• Employed multivariate Cox regression to evaluate biomarker independence for PFS and OS.

Main Results:

• The optimal prediction model for PFS and OS incorporated miR-375 and KLK3 (baseline and 1-month) with standard clinical parameters.
• Baseline miR-375 and detectable KLK3 at 1 month independently predicted shorter PFS.
• No independent association was found for these biomarkers with overall survival (OS).

Conclusions:

• Combining KLK3 and miR-375 measurements at baseline and 1 month with standard clinical parameters provides the most accurate prediction model for survival assessment in mCRPC.
• These early RNA biomarkers show potential for refining prognostic evaluations in mCRPC patients.