ORIGINAL ARTICLE Expression analysis of four long noncoding RNAs in breast cancer Mostafa Iranpour 1 & Mohammad Soudyab 1 & Lobat Geranpayeh 2 & Reza Mirfakhraie 1 & Eznollah Azargashb 3 & Abolfazl Movafagh 1 & Soudeh Ghafouri-Fard 1 Received: 3 August 2015 /Accepted: 21 September 2015 # International Society of Oncology and BioMarkers (ISOBM) 2015 Abstract Breast cancer is a molecularly heterogeneous dis- ease which necessitates a search for markers to provide a more specific classification of this disorder. Long noncoding RNAs as the important subset of noncoding transcripts have been shown to be involved in tumorigenic processes. So, they may be used as markers for early detection of cancer and evaluation of cancer prognosis. In addition, they can be ap- plied as therapeutic targets. In this study, we analyzed expres- sion of four long noncoding RNAs (lncRNAs) namely SOX2OT , PTPRG-AS1, ANRASSF1, and ANRIL in 38 breast cancer tissues and their adjacent noncancerous tissues (ANCTs). ANRASSF1 expression was not detected in any noncancerous tissue. All lncRNAs showed significant overex- pression in tumor tissues compared with ANCTs. No associ- ation was found between gene expressions and individual clinical data such as tumor stage, grade, size and hormone receptor status except for ANRASSF1 expression and Her2/neu status. In addition, ANRASSF1 and ANRIL expres- sions were significantly higher in triple negative samples. This study suggests a putative role for these lncRNAs in breast cancer and implies that they can be used as potential cancer biomarkers. Keywords Breast cancer . Long noncoding RNA . SOX2OT . PTPRG-AS1 . ANRASSF1 . ANRIL Introduction Breast cancer is a molecularly heterogeneous disease. Al- though it has been classified to luminal A and B, basal, ERBB2, and normal-like subtypes, recent data suggest that a great deal of the clinically recognizable plasticity and heterogeneity arises within, and not across, these ma- jor subtypes [1]. Such molecular and clinical heterogene- ity necessitates a search for molecular markers with the ability to predict patient outcome and choose the best treatment. The main purpose for identification of such prognostic and predictive signatures is the implementation of targeted individualized therapeutics and screening ap- proaches. Although several molecular markers in tran- scriptome as well as proteome have been proposed for breast cancer, none of them entered clinical practice due to the lack of sensitivity and specificity [2]. Of note, anal- ysis of mammalian transcriptomes has revealed that about half of the transcripts have no protein-coding potential. A subset of these noncoding transcripts are long noncoding RNAs (lncRNAs) that vary from 200 nucleotides to mul- tiple kilobases in length and function directly as RNAs [3]. They have been shown to play vital roles in the reg- ulation of cellular processes such as cell growth and apo- ptosis as well as cancer progression and metastasis [4]. Such roles have proposed them as master gene regulators in the genome with the ability to control protein-coding and noncoding genes [4]. Mostafa Iranpour and Mohammad Soudyab contributed equally to this work. * Soudeh Ghafouri-Fard ghafourifard@razi.tums.ac.ir 1 Department of Medical Genetics, Shahid Beheshti University of Medical Sciences, Tehran, Iran 2 Department of Surgery, Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran 3 Department of Social Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran Tumor Biol. DOI 10.1007/s13277-015-4135-2