Urine microRNAs Are Sensitive and Specific for Bladder Cancer: Results of a Pilot Study.
Jaime Snowdon, Xiao Zhang, Jason Izard, Alexander Boag, Robert Siemens, Harriet Feilotter. Queen's University, Kingston, ON, Canada
Background: Bladder cancer is the second most common urologic tumour. Voided urine cytology along with direct visualization of the bladder with cystoscopy are the primary methods for diagnosis and surveillance. However, the invasiveness of cystoscopy along with the poor sensitivity of cytology make these tests suboptimal. The aims of this pilot study are to determine whether urine microRNAs can be used to distinguish between patients with known bladder cancer and normal controls.
Design: Firstly, voided urine samples were collected from 8 patients with urothelial carcinoma and 5 control patients. Total RNA was isolated and quantitative RT-PCR was performed using primers for 4 microRNAs shown previously to be dysregulated in solid urothelial carcinomas with RNU6B as the endogenous control. Subsequently, those microRNAs that showed the highest fold change were investigated in an independent set of samples (n=8).
Results: Two microRNAs were found to be dysregulated in the urine from cancer patients with miR-A showing an average 10.42-fold decrease (p<0.05) and miR-B showing an average 2.70-fold increase (p=0.30) in the cancer samples compared to the normal controls. Using these 2 microRNAs, a prediction model was generated yielding an accuracy of 100%. When tested with an independent set of samples (5 with urothelial carcinoma and 3 controls), the levels of miR-A and miR-B enabled the detection of bladder cancer from urine with a sensitivity of 80% and a specificity of 100%.
Conclusions: This pilot study demonstrates that microRNAs are dysregulated in voided urine from cancer patients. Based on our prediction model which exploits the dysregulation of two microRNAs, we are able to detect bladder cancer from urine with a high sensitivity and specificity.
Category: Genitourinary (including renal tumors)
Monday, February 28, 2011 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 121, Monday Morning