Potential Biomarkers Identified for Patients With Prostate Cancer Treated With SBRT

Researchers have identified several proteins and molecular pathways that may serve as potential biomarkers in patients with prostate cancer treated with stereotactic body radiation therapy (SBRT).¹

For the study, researchers sought to determine the feasibility for developing prognostic protein biomarkers in serum samples from patients undergoing SBRT for localized prostate cancer. Researchers analyzed peripheral blood samples from 120 patients who received SBRT at doses between 35 and 36.25 Gy in 5 fractions. Peripheral blood samples were collected prior to radiation treatment, 24 hours after first treatment, at 1, 3, 6, 9, and 12 months during the first year, and every 6 months thereafter for up to 3 years.

Researchers found that proteins that play a role in cell proliferation, angiogenesis, protein signaling, gonad development, and cell migration correlated with Gleason grade. Furthermore, results showed that genes CGA, LHB, KLK3, and CNTFR correlated with both tumor stage and Gleason grade.

By comparing pre-treatment samples to 3-month post-treatment samples, researchers attributed 183 proteins to radiation effects. Analyses of these paired samples also demonstrated changes in cell activation and signaling pathways, with the primary regulatory networks associated with ERK1/2, NF-κB, IFNG, ADIPOQ, histone 3, and histone 4.

Results also revealed that high adiponectin levels in patients with higher tumor stage decreased following radiation exposure, indicating the potential for this molecule to serve as a biomarker for radiotherapy response.

Validation studies are required to determine which of these potential markers actually predict prostate cancer response to radiation treatment.

Reference

1. Janowski E, Suy S, Varghese RS, et al. Serum biomarkers in patients treated with stereotactic body radiation therapy (SBRT) for prostate cancer. Poster presentation at: AACR Annual Meeting 2016; April 16-20, 2016; New Orleans, LA.