[Frontiers in Bioscience, Scholar, 7, 94-108, June 1, 2015]

Roles of lncRNA in breast cancer

Yin Liu 1 , Sambad Sharma 1 , Kounosuke Watabe 1

1Department of Cancer Biology and Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Physiological functions of LncRNAs
    3.1. Epigenetic regulation
    3.2. Transcriptional regulation
    3.3. Post-transcriptional regulation
4. Oncogenic LncRNAs in breast cancer
    4.1. Proliferation and Apoptosis
      4.1.1. H19
      4.1.2. SRA
      4.1.3. LSINCT5
      4.1.4. Zfas1
      4.1.5. LncRNA-Smad7
      4.1.6. LOC554202
      4.1.7. UCA1
    4.2. Invasion and metastasis
      4.2.1. HOTAIR
    4.3. Cancer stemness
      4.3.1. SOX2OT
      4.3. FAL1
5. Tumor suppressive LncRNAs in breast cancer
    5.1. Proliferation and Apoptosis
      5.1.1. GAS5
    5.2. Invasion and metastasis
      5.2.1. XIST
6. Future directions
7. Reference

1. ABSTRACT

Recent systematic genomic studies have revealed a broad spectrum of lncRNAs that are involved in a variety of disease (diseases), including tumor progression, by regulating gene expression at epigenetic, transcriptional and post-transcriptional levels. However, their exact roles of physiological function and the mechanism (mechanisms) of action are yet to be clarified. In breast cancer research, several lncRNAs are identified as tumor driving oncogenic lncRNAs and few are identified as tumor suppressive lncRNAs. They are involved in cell growth, apoptosis, cell migration and invasiveness as well as cancer cell stemness. Therefore, this new class of RNAs may serve as biomarkers for diagnostic and prognostic purpose and also as potential therapeutic targets. This review summarizes the current information about lncRNAs that are particularly involved in breast cancer progression and also discusses the potential translational application of these newly discovered nucleic acids.

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Key Words: Long non-coding RNAs, Breast cancer

Send correspondence to: Kounosuke Watabe, Department of Cancer Biology and Comprehensive Cancer Center, Wake Forest University School of Medicine, Winston-Salem, North Carolina, Tel: 336-716-0231, Fax: 336-716-0255, E-mail: kwatabe@wakehealth.edu