Researchers from The Ohio State University Comprehensive Cancer Center (OH, USA) have discovered that microRNAs (miRNA) in prostate cancer cells could help to determine which patients should be treated with radiation therapy if rising prostate-specific antigen (PSA) levels indicate their cancer has recurred after surgery. The results of the study were published recently in the journal PLOS ONE.
Prostate removal is widely utilized to treat men with early-stage disease. However, up to 30–40% of patients experience rising PSA levels, which are currently used as indicators of tumor recurrence, following surgery. These patients are commonly treated with radiation therapy.
The researchers analyzed tumor samples taken from 43 prostate cancer patients who all later received radiation therapy after rising PSA levels were detected following prostatectomy.
The study indicated that a pattern of miRNAs in tumor cells might allow successful prediction of patients’ responses to radiation therapy. Two miRNAs in particular, termed miR-4516 and miR-601, were highlighted as potentially useful for identifying patients who might experience rising PSA following radiation therapy, along with Gleason score and lymph node status.
“This study is the first to demonstrate that miRNA expression in tumor cells correlates with outcome after salvage radiation therapy, paving the way for the potential use of miRNA biomarkers in prostate cancer treatment,” explained Erica Hlavin Bell (The Ohio State University Comprehensive Cancer), the first author of the study.
In addition to these findings, the researchers correlated a pattern of 88 miRNAs with tumors that first recurred within 3 years or less post-prostatectomy versus tumors that recurred after 3 years.
“If validated by further studies, these findings could change clinical practice and improve the care of prostate cancer patients,” commented Arnab Chakravarti (The Ohio State University Comprehensive Cancer), the study leader.
“Men found to have aggressive disease at the time of prostatectomy could be offered additional treatment with radiation therapy to prevent recurrence, while sparing men with slow growing tumors,” added Chakravarti. “These findings are important because it is currently hard to distinguish early which patients will benefit from radiation therapy following radical prostatectomy and which will receive no benefit,” explained Bell. “Our novel miRNA panel might also shed light on the underlying mechanisms of treatment resistance in prostate cancer.”