Long noncoding RNA CDKN2B-AS1 silencing protects against esophageal cancer cell invasion and migration by inactivating the TFAP2A/FSCN1 axis

Kaohsiung J Med Sci. 2022 Dec;38(12):1144-1154. doi: 10.1002/kjm2.12596. Epub 2022 Sep 26.

Abstract

Esophageal cancer (EC) is the most aggressive malignancy in the gastrointestinal tract. Long noncoding RNA cyclin-dependent kinase inhibitor 2 B antisense RNA 1 (CDKN2B-AS1) is implicated in EC development. However, the specific mechanisms involved remain poorly defined. Therefore, this research aimed to explore the mechanism of action of CDKN2B-AS1 in EC. Quantitative real-time polymerase chain reaction was conducted to measure CDKN2B-AS1 expression in EC cells and western blotting was utilized to evaluate transcription factor AP-2 alpha (TFAP2A) and fascin actin-bundling protein 1 (FSCN1) expression. After gain-of-function and loss-of-function assays, cell proliferation, migration, invasion, apoptosis, and apoptosis-related protein expression were assessed using cell counting kit-8, scratch tests, Transwell assays, flow cytometry, and western blotting, respectively. The binding relationship between CDKN2B-AS1 and TFAP2A was assessed by RNA immunoprecipitation and RNA pull-down assays. The binding relationship between TFAP2A and FSCN1 was evaluated using dual-luciferase reporter and chromatin immunoprecipitation assays. Tumor xenografts from nude mice were used for in vivo verification. CDKN2B-AS1, TFAP2A, and FSCN1 were upregulated in EC cells. Mechanistically, CDKN2B-AS1 transcriptionally activated FSCN1 by recruiting TFAP2A to the FSCN1 promoter. Silencing CDKN2B-AS1 or TFAP2A suppressed EC cell proliferative, migrating, and invasive properties and augmented apoptosis. TFAP2A was bound to CDKN2B-AS1 and the FSCN1 promoter. Overexpression of TFAP2A or FSCN1 abolished the effects of CDKN2B-AS1-silencing on EC cell function. CDKN2B-AS1 silencing curtailed tumorigenesis in nude mice, which was nullified by the upregulation of TFAP2A or FSCN1. Our findings demonstrated the antioncogenic effects of silencing CDKN2B-AS1 in EC through inactivation of the TFAP2A/FSCN1 axis.

Keywords: esophageal cancer; fascin actin-bundling protein 1; long noncoding RNA CDKN2B-AS1; malignant behaviors; transcription factor AP-2 alpha.

MeSH terms

  • Animals
  • Carrier Proteins / genetics
  • Cell Line, Tumor
  • Cell Movement / genetics
  • Cell Proliferation / genetics
  • Esophageal Neoplasms* / genetics
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Mice
  • Mice, Nude
  • MicroRNAs* / genetics
  • Microfilament Proteins / genetics
  • Microfilament Proteins / metabolism
  • Neoplasm Invasiveness / genetics
  • RNA, Long Noncoding* / genetics
  • RNA, Long Noncoding* / metabolism
  • Transcription Factor AP-2 / genetics
  • Transcription Factor AP-2 / metabolism

Substances

  • RNA, Long Noncoding
  • Transcription Factor AP-2
  • MicroRNAs
  • TFAP2A protein, human
  • FSCN1 protein, human
  • Carrier Proteins
  • Microfilament Proteins