S1. The relative expression of KLK3/PSA. S2. Kaplan-Meier analysis of prostate cancer outcome was obtained from GEPIA tool. S3. LNCaP cells with the indicated treatments were seeded in the upper chamber of the Boyden's transwell chamber. S4. LNCaP cells with the indicated treatments were seeded in the upper chamber of the Boyden's transwell chamber which were coated with 1:20 diluted Matrigel. S5. LNCaP cells with the indicated treatments were seeded in the upper chamber of the Boyden's transwell chamber. S6. Snapshots form the AR ChIP-seq showing AR binding to the ARBS. S7. Screenshot from the AR ChIP-seq shows marked reduction in AR binding to the ARBS located at ~ 30kb from the NDRG1 after LINC00844 knock-down in LNCaP cells. S8. LNCaP cells with the indicated treatments were seeded in the upper chamber of the Boyden's transwell chamber. S9. LNCaP cells we co-transfected with the with the indicated siRNA and plasmids and seeded in the upper chamber of the Boyden's transwell chamber. S10. LNCaP cells we co-transfected with the with the indicated siRNA and plasmids cells were harvested and the required amount of cells were used for the migration and invasion assay and rest were lysed for western blot analysis.
Funding
University of Macau Multi-Year Research
University of Macau Start-up Research Grant
Macau Science and Technology Development Fund
ARTICLE ABSTRACT
The human genome is mostly transcribed, yielding a rich repository of noncoding transcripts that are involved in a myriad of biological processes including cancer. However, how many noncoding transcripts such as long noncoding RNAs (lncRNA) function in cancer is still unclear. This study identified a novel set of clinically relevant androgen-regulated lncRNAs in prostate cancer. Among this group, LINC00844 was demonstrated to be a direct androgen-regulated target that is actively transcribed in androgen receptor (AR)–dependent prostate cancer cells. The expression of LINC00844 is higher in normal prostate compared with malignant and metastatic prostate cancer clinical specimens, and patients with low expression had a poor prognosis and significantly increased biochemical recurrence, suggesting LINC00844 functions in suppressing tumor progression and metastasis. Indeed, in vitro loss-of-function studies revealed that LINC00844 prevents prostate cancer cell migration and invasion. Moreover, findings from gene expression profiling analysis indicated that LINC00844 functions in trans, affecting global androgen-regulated gene transcription. Mechanistic evidence reveals that LINC00844 is important in facilitating AR binding to the chromatin. Finally, LINC00844 mediates its phenotypic effects in part by activating the expression of NDRG1, a crucial cancer metastasis suppressor. Collectively, LINC00844 is a novel coregulator of AR that plays a central role in the androgen transcriptional network and the development and progression of prostate cancer.
This study highlights the function of the lncRNA, LINC00844, in regulating global AR-regulated genes in prostate cancer by modulating AR binding to chromatin.
