Zeynab Shaghaghi Torkdari - Associate Professor, Department of Genetics, Animal biology Group, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
Mohammad Khalaj Kondori - PHD student, Department of Genetics, Animal biology Group, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
Mohammad Ali Hosseinpour Feizi - Department of Animal Biology, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran
Vahid Montazeri - Department of Thorax Surgery, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran

Introduction & Aim: Breast cancer (BC) is the second most common cause of cancer-related death amongst females which requires an exploration for markers to propose a more specific categorization of this cancer. Long noncoding RNAs (lncRNAs) as the main subset of noncoding transcripts have been shown to be involved in tumorigenic processes. In this study, we investigated expression of differentiation antagonizing non-protein coding RNA (DANCR) and its ceRNA network target gene, catenin beta 1(CTNNB1), in 61 breast cancer tissues and their adjacent noncancerous tissues (ANCTs). Furthermore, the relationship of lncRNA DANCR and CTNNB1 gene with various clinical features of patients were analyzed. Methods: The expression of mentioned genes was assessed by quantitative real time-PCR in 61 samples of invasive ductal carcinoma of breast in comparison with their ANCTs in a cohort of Iranian Turkish breast cancer patients. Results: DANCR and CTNNB1 genes have been shown to be down-regulated in breast tumor samples compared with their paired ANCTs (P=0.008). In addition, the results showed that the expression of lncRNA DANCR and CTNNB1gene was significantly associated with histological grade, TNM stages, lymph node involvement and also metastasis (P<0.05). Conclusion: DANCR and CTNNB1 genes usually are up-regulated in various cancers including hepatocellular carcinoma, colorectal and breast cancers. In contrast to the previous studies about breast cancer, in our cohort a down-regulation of DANCR lncRNA in BC was found which supports recent investigation of Foroughi.et al on gastric cancer tissues.