The Melanoma-Upregulated Long Noncoding RNA SPRY4-IT1 Modulates Apoptosis and Invasion

• Published in: Cancer research (Chicago, Ill.) Vol. 71; no. 11; pp. 3852 - 3862
• Main Authors: KHAITAN, Divya, DINGER, Marcel E, MAZAR, Joseph, CRAWFORD, Joanna, SMITH, Martin A, MATTICK, John S, PERERA, Ranjan J
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA American Association for Cancer Research 01-06-2011
• Subjects: Antineoplastic agents; Apoptosis - genetics; Base Sequence; Biological and medical sciences; Cell Line, Tumor; Cell Movement - genetics; Dermatology; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Gene Knockdown Techniques; Humans; Intracellular Signaling Peptides and Proteins - genetics; Intracellular Signaling Peptides and Proteins - metabolism; Medical sciences; Melanoma - genetics; Melanoma - pathology; Molecular Sequence Data; Neoplasm Invasiveness; Nerve Tissue Proteins - biosynthesis; Nerve Tissue Proteins - genetics; Nerve Tissue Proteins - metabolism; Pharmacology. Drug treatments; RNA, Untranslated - genetics; RNA, Untranslated - metabolism; Transfection; Tumors; Tumors of the skin and soft tissue. Premalignant lesions; Up-Regulation; RNA; Cell death; Malignant melanoma; Non coding sequence; Malignant tumor; Metastasis; Invasion; Cancer; Apoptosis
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/0008-5472.can-10-4460

The identification of cancer-associated long noncoding RNAs (lncRNAs) and the investigation of their molecular and biological functions are important to understand the molecular biology of cancer and its progression. Although the functions of lncRNAs and the mechanisms regulating their expression are largely unknown, recent studies are beginning to unravel their importance in human health and disease. Here, we report that a number of lncRNAs are differentially expressed in melanoma cell lines in comparison to melanocytes and keratinocyte controls. One of these lncRNAs, SPRY4-IT1 (GenBank accession ID AK024556), is derived from an intron of the SPRY4 gene and is predicted to contain several long hairpins in its secondary structure. RNA-FISH analysis showed that SPRY4-IT1 is predominantly localized in the cytoplasm of melanoma cells, and SPRY4-IT1 RNAi knockdown results in defects in cell growth, differentiation, and higher rates of apoptosis in melanoma cell lines. Differential expression of both SPRY4 and SPRY4-IT1 was also detected in vivo, in 30 distinct patient samples, classified as primary in situ, regional metastatic, distant metastatic, and nodal metastatic melanoma. The elevated expression of SPRY4-IT1 in melanoma cells compared to melanocytes, its accumulation in cell cytoplasm, and effects on cell dynamics, including increased rate of wound closure on SPRY4-IT1 overexpression, suggest that the higher expression of SPRY4-IT1 may have an important role in the molecular etiology of human melanoma.