Cancer-Specifically Re-Spliced TSG101 mRNA Promotes Invasion and Metastasis of Nasopharyngeal Carcinoma

Int J Mol Sci. 2019 Feb 12;20(3):773. doi: 10.3390/ijms20030773.

Abstract

TSG101 (Tumor susceptibility 101) gene and its aberrantly spliced isoform, termed TSG101∆154-1054, are tightly linked to tumorigenesis in various cancers. The aberrant TSG101∆154-1054 mRNA is generated from cancer-specific re-splicing of mature TSG101 mRNA. The TSG101∆154-1054 protein protects the full-length TSG101 protein from ubiquitin-mediated degradation, implicating TSG101∆154-1054 protein in the progression of cancer. Here, we confirmed that the presence of TSG101∆154-1054 mRNA indeed caused an accumulation of the TSG101 protein in biopsies of human nasopharyngeal carcinoma (NPC), which was recapitulated by the overexpression of TSG101∆154-1054 in the NPC cell line TW01. We demonstrate the potential function of the TSG101∆154-1054 protein in the malignancy of human NPC with scratch-wound healing and transwell invasion assays. By increasing the stability of the TSG101 protein, TSG101∆154-1054 specifically enhanced TSG101-mediated TW01 cell migration and invasion, suggesting the involvement in NPC metastasis in vivo. This finding sheds light on the functional significance of TSG101∆154-1054 generation via re-splicing of TSG101 mRNA in NPC metastasis and hints at its potential importance as a therapeutic target.

Keywords: TSG101; TSG101∆154-1054; invasion; metastasis; nasopharyngeal carcinoma; re-splicing.

MeSH terms

  • Adult
  • Carcinogenesis / genetics
  • Cell Line, Tumor
  • Cell Movement / genetics
  • DNA-Binding Proteins / genetics*
  • Endosomal Sorting Complexes Required for Transport / genetics*
  • Female
  • Gene Expression Regulation, Neoplastic / genetics
  • Humans
  • Male
  • Middle Aged
  • Nasopharyngeal Carcinoma / genetics*
  • Nasopharyngeal Carcinoma / pathology
  • Nasopharyngeal Neoplasms / genetics*
  • Nasopharyngeal Neoplasms / pathology
  • Neoplasm Invasiveness
  • Neoplasm Metastasis / genetics*
  • RNA Splicing / genetics*
  • RNA, Messenger / genetics*
  • Transcription Factors / genetics*

Substances

  • DNA-Binding Proteins
  • Endosomal Sorting Complexes Required for Transport
  • RNA, Messenger
  • Transcription Factors
  • Tsg101 protein