Downregulation of long noncoding RNA MALAT1 induces epithelial-to-mesenchymal transition via the PI3K-AKT pathway in breast cancer

Int J Clin Exp Pathol. 2015 May 1;8(5):4881-91. eCollection 2015.


The metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) regulates cell motility via the transcriptional or post-transcriptional control of motility-related genes. Whether MALAT1 plays a critical role in cancer progression in breast cancer remains unclear. In this study, we found that MALAT1 was downregulated in breast tumor cell lines and cancer tissue, and showed that knockdown of MALAT1 in breast cancer cell lines induced an epithelial-to-mesenchymal transition (EMT) program via phosphatidylinositide-3 kinase-AKT pathways. Furthermore, lower expression of MALAT1 in breast cancer patients was associated with shorter relapse-free survival. Thus, our results indicate for the first time that MALAT1 is a novel regulator of EMT in breast cancer and may be a potential therapeutic target for breast cancer metastasis.

Keywords: EMT; Long noncoding RNA; MALAT1; breast cancer; metastasis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breast Neoplasms / enzymology*
  • Breast Neoplasms / genetics
  • Breast Neoplasms / pathology
  • Disease-Free Survival
  • Down-Regulation
  • Epithelial-Mesenchymal Transition*
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Kaplan-Meier Estimate
  • Lymphatic Metastasis
  • MCF-7 Cells
  • Middle Aged
  • Neoplasm Recurrence, Local
  • Phosphatidylinositol 3-Kinase / metabolism*
  • Prognosis
  • Proto-Oncogene Proteins c-akt / metabolism*
  • RNA Interference
  • RNA, Long Noncoding / genetics
  • RNA, Long Noncoding / metabolism*
  • Risk Factors
  • Signal Transduction
  • Time Factors
  • Transfection


  • MALAT1 long non-coding RNA, human
  • RNA, Long Noncoding
  • Phosphatidylinositol 3-Kinase
  • Proto-Oncogene Proteins c-akt