An ER-associated miRNA signature predicts prognosis in ER-positive breast cancer.

Xin Zhou,Wei Zhu,Xiaping Wang,Ping Liu,Lei Xu,Zebo Huang

doi:10.1186/s13046-014-0094-5

Abstract

BackgroundBreast cancer patients with positive estrogen receptor (ER) have a better prognosis. However, no prognostic miRNA signature was reported in the ER-positive breast cancer. The aim of the study was to identify and assess the prognostic significance of a miRNA signature in ER-positive breast cancer.MethodsTwo cohorts from The Cancer Genome Atlas (TCGA) dataset were used as training (n =596) and testing set (n =319). Differential expression profiling was identified in the training set. And the prognostic value of the miRNA signature was then assessed in the two cohorts.ResultsA total of 14 miRNAs were observed to be associated with the status of ER by significance analysis of microarrays (SAM) in the training set. Patients were characterized as high score or low score group according to the calculated risk scores from each miRNA. And patients in high score group had worse overall survival compared with those in low score group both in the training and testing set.ConclusionsOur study revealed a miRNA signature including 14 miRNAs associated with ER status which could act as a prognostic marker in ER-positive breast cancer.Electronic supplementary materialThe online version of this article (doi:10.1186/s13046-014-0094-5) contains supplementary material, which is available to authorized users.

Highlights

Breast cancer is a heterogeneous disease that comprises a range of subgroups with diverse clinical behaviors and responses to treatment [1]
Statistical analysis The differential expression profile between estrogen receptor (ER)-positive and ER-negative cases in training set was assessed by using significance analysis of microarrays (SAM) on BRB array tools package which was developed by Richard Simon and the BRB-ArrayTools Development Team [24]
Identification of ER associated miRNA signature A total of 14 miRNAs were identified to be associated with ER status in the training set

Summary

Introduction

Breast cancer is a heterogeneous disease that comprises a range of subgroups with diverse clinical behaviors and responses to treatment [1]. Many breast-cancer-related genes have been investigated to explore the molecular mechanism of carcinogenesis and diverse clinical outcome of the disease [2,3,4,5,6]. Patients with ER-positive status which account for almost 70% of breast cancer always had a better prognosis compared with those ER-negative types [10]. Breast cancer patients with positive estrogen receptor (ER) have a better prognosis. No prognostic miRNA signature was reported in the ER-positive breast cancer. The aim of the study was to identify and assess the prognostic significance of a miRNA signature in ER-positive breast cancer

Objectives

Methods

Results