Abstract LB-350: Tissue and serum miRNA profiling for detection of bladder, breast and prostate cancer

Biomarkers that can differentiate between normal and tumor state, and can be measured in easily accessible body fluids such as blood and urine, can be very important for cancer diagnostics and disease monitoring. MicroRNAs (miRNAs), short non-coding regulatory RNA molecules, are attractive as biomarkers because they are stable in different conditions and are easy to measure with quantitative PCR (qPCR) methods. In this study we aimed to identify a universal panel of miRNAs for cancer screening that can be easily tested in the serum of healthy individuals and patients with different types of cancer. First, we measured expression of ∼800 miRNAs in 40 controls and 60 patients with bladder, breast or prostate cancer using the low density TaqMan expression arrays (Applied Biosystems) and starting from 250 ul of serum. Based on these results we selected a panel of 24 miRNAs that showed best discrimination between normal and cancer samples. These miRNAs were then re-tested as a custom-designed mini-panel in serum samples of 44 healthy controls and cancer patients (31 bladder, 25 breast and 28 prostate) and in relevant normal and tumor tissue samples (42 normal bladder and 43 bladder tumors, 44 normal breast and 42 breast tumors and in 50 normal prostate and 20 prostate tumors). Only miRNAs that expressed in the same direction in serum and tissue samples and showed significant association with cancer in both sample types were used for further analysis. The current panel consists of 16 miRNAs – 14 targets, one positive control and one negative control. Using this panel on serum samples from 44 controls, 31 bladder cancer patients, 25 breast cancer patients and 28 prostate cancer patients we performed ROC analysis and achieved complete discrimination (AUC ∼1.0) between all types of cancers and controls and good discrimination between different types of cancers (minimal AUC 0.89 for breast and bladder samples). Our results prove that miRNA detection from serum might be a promising method of cancer detection. Currently, we are performing validation studies in independent sets of samples. A combination of information on genetic susceptibility factors identified by genome-wide association studies (GWAS), other cancer-specific factors such as PSA for prostate cancer and miRNA expression profiling, might provide additional tools for early disease diagnostics and help to guide treatment options. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-350. doi:10.1158/1538-7445.AM2011-LB-350