Recently, we reported that the long noncoding RNA (lncRNA) SPRY4-IT1, which lies within the intronic region of the Sprouty4 gene, is upregulated in human melanomas and influences cell growth, proliferation, and motility, suggesting it may play an important role in the molecular etiology of human melanomas. Here, we report the identification of the full-length of SPRY4-IT1 transcript and its molecular function in human melanoma cells. SPRY4-IT1 transcripts are predominantly found in cytoplasm and accumulate in the polysome fraction of the cell suggests that they may interact with cellular proteins and/or interact with mRNAs to modulate the protein translation. We have identified a group of SPRY4-IT1 interacting proteins by isolating SPRY4-IT1 and protein binding complex and further characterization by mass spectrometry analysis. When SPRY4-IT1 ectopically expressed in melanocytes, it induced formation of multinucleated giant cells and modulates the expression of many genes including a subset of anti-apoptotic, cell cycle regulatory, DNA packaging, chromosome organization and chromatin architecture genes. Notably, the downregulation of the tumor suppressor gene dipeptidyl peptidase IV (DPPIV) and the upregulation the cellular proliferation marker Ki67 indicates the relevance of SPRY4-IT1 in the transition of melanocytes to melanomas.

Citation Format: Wei Zhao, Joseph Mazar, Jian-Liang Li, Lawrence M. Brill, Maya Ratnam, Ahmad M. Khalil, John S. Mattick, Marcel E. Dinger, Ranjan J. Perera. Molecular function of the long noncoding RNA SPRY4-IT1 in human melanomas. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1914. doi:10.1158/1538-7445.AM2013-1914

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.