HCP5 is a SMAD3-responsive long non-coding RNA that promotes lung adenocarcinoma metastasis via miR-203/SNAI axis

Theranostics. 2019 Apr 13;9(9):2460-2474. doi: 10.7150/thno.31097. eCollection 2019.

Abstract

Introduction: Transforming growth factor-beta (TGFβ) signaling plays a vital role in lung adenocarcinoma (LUAD) progression. However, the involvement of TGFβ-regulated long non-coding RNAs (lncRNAs) in metastasis of LUAD remains poorly understood. Methods: We performed bioinformatic analyses to identify putative lncRNAs regulated by TGF-β/SMAD3 and validated the results by quantitative PCR in LUAD cells. We performed luciferase reporter and chromatin immunoprecipitation assays to demonstrate the transcriptional regulation of the lncRNA histocompatibility leukocyte antigen complex P5 (HCP5) we decided to focus on. Stable HCP5 knockdown and HCP5-overexpressing A549 cell variants were generated respectively, to study HCP5 function and understand its mechanism of action. We also confirmed our findings in mouse xenografts and metastasis models. We analyzed the correlation between the level of lncRNA expression with EGFR, KRAS mutations, smoke state and prognostic of LUAD patients. Results: We found that the lncRNA HCP5 is induced by TGFβ and transcriptionally regulated by SMAD3, which promotes LUAD tumor growth and metastasis. Moreover, HCP5 is overexpressed in tumor tissues of patients with LUAD, specifically in patients with EGFR and KRAS mutations and current smoker. HCP5 high expression level is positively correlated with poor prognosis of patients with LUAD. Finally, we demonstrated that upregulation of HCP5 increases the expression of Snail and Slug by sponging the microRNA-203 (miR-203) and promoting epithelial-mesenchymal transition (EMT) in LUAD cells. Conclusions: Our work demonstrates that the lncRNA HCP5 is transcriptionally regulated by SMAD3 and acts as a new regulator in the TGFβ/SMAD signaling pathway. Therefore, HCP5 can serve as a potential therapeutic target in LUAD.

Keywords: HCP5; Long non-coding RNA; SMAD3; lung adenocarcinoma; metastasis..

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • A549 Cells
  • Adenocarcinoma of Lung / diagnosis
  • Adenocarcinoma of Lung / genetics*
  • Adenocarcinoma of Lung / mortality
  • Adenocarcinoma of Lung / pathology
  • Animals
  • Cell Line, Tumor
  • Cell Proliferation
  • ErbB Receptors / genetics
  • ErbB Receptors / metabolism
  • Female
  • Gene Expression Regulation, Neoplastic*
  • Humans
  • Lung Neoplasms / diagnosis
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / mortality
  • Lung Neoplasms / pathology
  • Lymphatic Metastasis
  • Mice
  • Mice, Nude
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Oligoribonucleotides / genetics
  • Oligoribonucleotides / metabolism
  • Prognosis
  • Proto-Oncogene Proteins p21(ras) / genetics
  • Proto-Oncogene Proteins p21(ras) / metabolism
  • RNA, Long Noncoding / agonists
  • RNA, Long Noncoding / antagonists & inhibitors
  • RNA, Long Noncoding / genetics*
  • RNA, Long Noncoding / metabolism
  • Signal Transduction
  • Smad3 Protein / genetics*
  • Smad3 Protein / metabolism
  • Snail Family Transcription Factors / genetics*
  • Snail Family Transcription Factors / metabolism
  • Survival Analysis
  • Transforming Growth Factor beta1 / genetics
  • Transforming Growth Factor beta1 / metabolism
  • Tumor Burden
  • Xenograft Model Antitumor Assays

Substances

  • HCP5 long noncoding RNA, human
  • KRAS protein, human
  • MIRN203 microRNA, human
  • MicroRNAs
  • Oligoribonucleotides
  • RNA, Long Noncoding
  • SMAD3 protein, human
  • SNAI1 protein, human
  • Smad3 Protein
  • Snail Family Transcription Factors
  • TGFB1 protein, human
  • Transforming Growth Factor beta1
  • EGFR protein, human
  • ErbB Receptors
  • Proto-Oncogene Proteins p21(ras)