Prostate cancer is a heterogeneous disease that is driven by combined genetic and epigenetic alterations. A significant portion of the mammalian genome consists of non-coding regions of RNA. Increasing evidence has shown that these noncoding RNAs (ncRNAs) have significant roles in the epigenetic regulation of several cellular processes, and their dysregulation can contribute to tumorigenesis and promote disease progression in many cancer types. In order to gain better insights into the potential roles of ncRNAs in prostate cancer, we used a genetically engineered mouse model of prostate cancer to perform a comparative analysis of the cancer transcriptome and the landscape of ncRNAs in castration-naïve prostate tumors and the progression to castration-resistant disease. Whole transcription arrays were used to explore both messenger (mRNA) and long intergenic non-coding RNA (LincRNA) transcript expression in normal prostate tissue from wildtype mice and prostate tumors from conditional PTEN-knockout mice. Comparative analyses were performed between prostate tumor samples from castration-naïve mice and, at 4 weeks and 10 weeks post-surgical castration. Altered expression of ncRNAs was most commonly observed and accounted for 56.2% (2370/4216), 47.6% (4460/9366) and 41.57% (1545/3717) of the total genes differentially expressed between normal mouse prostate and prostate tumors from castration-naïve, 4 weeks post-castration and 10 weeks post-castration, respectively. We also profile the expression of relevant cancer-related lincRNAs present in these models. Overall, our analyses provide data to support a role of LincRNA dysregulation in the pathogenesis of PTEN-deficient prostate cancer, and suggest that these mouse models might provide a potential preclinical tool to test candidate prospective therapies targeting ncRNAs.

Citation Format: Marco A. De Velasco, Yurie Kura, Kazuko Sakai, Yuji Hatanaka, Yoshihiko Fujita, Yosuke Togashi, Masato Terashima, Kazuhiro Yoshikawa, Kazuto Nishio, Hirotsugu Uemura. Analysis of noncoding RNA expression in a mouse model of PTEN-deficient prostate cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 954.