Urine cell-free DNA integrity as a marker for early prostate cancer diagnosis: a pilot study

Circulating cell-free DNA has been recognized as an accurate marker for the diagnosis of prostate cancer, whereas the role of urine cell-free DNA (UCF DNA) has never been evaluated in this setting. It is known that normal apoptotic cells produce highly fragmented DNA while cancer cells release longer DNA. We thus verified the potential role of UCF DNA integrity for early prostate cancer diagnosis. UCF DNA was isolated from 29 prostate cancer patients and 25 healthy volunteers. Sequences longer than 250 bp (c-Myc, BCAS1, and HER2) were quantified by real-time PCR to verify UCF DNA integrity. Receiver operating characteristic (ROC) curve analysis revealed an area under the curve of 0.7959 (95% CI 0.6729-0.9188). At the best cut-off value of 0.04 ng/μL, UCF DNA integrity analysis showed a sensitivity of 0.79 (95% CI 0.62-0.90) and a specificity of 0.84 (95% CI 0.65-0.94). These preliminary findings indicate that UCF DNA integrity could be a promising noninvasive marker for the early diagnosis of prostate cancer and pave the way for further research into this area.