LncRNA LINC00152 promotes oral squamous cell carcinoma growth via enhancing Upstream Transcription Factor 1 mediated Mitochondrial Ribosomal Protein L52 transcription.

Abstract

LINC00152 (long intergenic non-protein coding RNA 152) was identified as an oncogenic lncRNA in multiple cancers. In the current study, we aimed to explore the transcriptional profile of LINC00152 in oral squamous cell carcinoma (OSCC) and its regulations at the transcriptional level. Bioinformatic analysis was performed by extracting the OSCC subset from The Cancer Genome Atlas (TCGA)-Head and Neck Squamous Cell Carcinoma (HNSC). LINC00152subcellular localization and its interacting transcriptional factors (TFs) were explored. Dual-luciferase assay and ChIP-qPCR were applied to study transcriptional regulation. In vitro and in vivo tumor cell growth models were used for functional assays. NR_024206.2 was the dominant isoform that accounts for 80% of all transcripts of LINC00152. LINC00152 upregulation was associated with unfavorable survival of patients with OSCC. LINC00152knockdown significantly impaired OSCC cell growth in vitro and in vivo. RNA FISH assay confirmed nuclear and cytoplasmic distribution of LINC00152. It physically interacted with Upstream Transcription Factor 1 (USF1), a common transcription factor in mammalian cells. USF1 could bind to the promoter region of MRPL52 (Mitochondrial Ribosomal Protein L52) and activate its transcription. LINC00152 could enhance the binding, thereby indirectly elevating MRPL52 expression. USF1 or MRPL52knockdown slowed the proliferation of OSCC cells and partly canceled LINC00152-mediated growth-promoting effects. This study revealed a novel LINC00152-USF1/MRPL52 axis promoting OSCC tumor growth.