Abstract B39: Long noncoding RNA PCAT14/PRCAT104; A prognostic biomarker in prostate cancer

Abstract

Abstract Prostate cancer is the second most common epithelial cancer and the second leading cause of cancer-related death for men in the United States. While majority of prostate cancer cases are indolent and cause minimal morbidity and mortality, a subset of men progress to a hormone-refractory aggressive disease with high mortality. Markers such as PSA and PCA3 perform well in diagnosis of disease; however these biomarkers are unable to predict disease progression. Therefore, there is an urgent need to identify clinical predictors of disease progression. Long non-coding RNAs (lncRNAs) are emerging as an important class of biomolecules that exhibit significant lineage- and cancer-specificity making them ideal biomarker candidates. Using RNA-Seq data from The Cancer Genome Atlas (TCGA) and as well as from libraries generated in our laboratory, we identified PCAT14/PRCAT104 as a marker of low Gleason disease. PCAT14 was shown to be highly expressed in prostate cancer compared to benign tissue; however, its expression in prostate cancer was limited to low Gleason disease. To directly evaluate the relationship between PCAT14 levels and clinical outcome, we assessed its expression in more that 1600 Prostate cancer samples by a high-density Affymetrix GeneChip platform. In all 5 cohorts analyzed, PCAT14 was shown to be a strong prognostic marker in its ability to predict biochemical recurrence, clinical progression to systemic disease and prostate cancer–specific mortality. Furthermore, in a multivariate analysis, PCAT14 expression also predict resistance to androgen deprivation therapy (ADT) (p=0.012). More interestingly, PCAT14 was able to add to prognostic value of SCHLAP1, a lncRNA that we previously showed to be an excellent prognostic marker in prostate cancer. PCAT14 in combination with SCHLAP1 was able better in predicting 10-year metastasis free survival (AUC: 0.64) than SCHLAP1 alone (AUC=0.58). Taken together, we identified a novel marker of low grade prostate cancer that in combination with SCHALP1, a marker of aggressive cancer, can predict disease progression and hence can be of immense value for treatment individualization in prostate cancer Citation Format: Rohit Malik, Xiang Zhang, Sudhanshu Shukla, Yashar Y. Niknafs, Shuang Zhao, Felix Y. Feng, Arul M. Chinnaiyan. Long noncoding RNA PCAT14/PRCAT104; A prognostic biomarker in prostate cancer. [abstract]. In: Proceedings of the AACR Special Conference on Noncoding RNAs and Cancer: Mechanisms to Medicines ; 2015 Dec 4-7; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2016;76(6 Suppl):Abstract nr B39.