microRNA expression profiling in tumor prostate samples from recurrent and non-recurrent cases

We investigated the relative miRNA levels in primary prostate cancer samples from patients that had a subsequent recurrence event versus patients that did not. For one of the top miRNAs arising from this analysis, miR-33a, we carried out further investigation, including miRNA levels in normal and tumor prostate samples as well as PCa cell lines. Then, we performed a detailed functional analysis of mir-33a in LNCaP and VCaP PCa cells and evaluated proliferative, invasive and anchorage independent growth potential of cells upon overexpression and knockdown of miR-33a. Two groups of tumor samples from prostate cancer patients: recurrent versus non-recurrent. Recurrence was defined as two consecutive serum PSAs greater than 0.2 ng/ml. Patients were followed for until PSA recurrence or at least 4 years (for non-recurrent cases).