Downregulation of LINC02615 Is Correlated with The Breast Cancer Progress: A Novel Biomarker for Differential Identification of Breast Cancer Tissues

Objective: Breast cancer is one of the most frequent types of cancer with a gradually increasing incidence in developing countries. The aim of this study was to assess modulation of LINC02615 levels in breast cancer progress, using pairwise breast cancer and healthy control tissue samples with regard to the obesity and other conditions, as estrogen receptor (ER) expression. Materials and Methods: In this cohort study, the genes, microRNAs (miRNAs) and long non-coding RNAs (lncRNAs) in several important pathways of chromosomal instability, apoptosis and proliferation were analyzed through in silico studies pinpointing the important genes which were responsible for the breast cancer incidence. Then, the respective miRNAs and lncRNAs were selected by relevant databases. At the next step, Lncbase was used for interaction analysis of selected miRNAs and LncRNAs, which resulted in final selection of LINC02615. Total RNA was isolated from 24 pairwise breast cancer and healthy control tissue samples. Expression profile of LINC02615 was assessed using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Correlation between LINC02615 expression and clinicopathological characteristics were analyzed using Pearson's Chi-square test in breast cancer patients. Results: Data demonstrated that expression of LINC02615 was significantly downregulated in breast cancer tissues compared to the healthy controls (P=0.046). In particular, the relative LINC02615 expression was significantly different in breast cancer tissues especially in obese patients compared to those persons without obesity (P=0.047). Furthermore, a significant difference in LINC02615 level was found between the high and low ER expressions (P=0.014). However, the aberrant expression of LINC02615 was significantly related to physical activity and diabetes disease as well as the stress and age at menopause (P=0.028, P=0.046, P=0.047 and P=0.025, respectively). Conclusion: Taken together, we suggest that LINC02615 downregulation may be related to the risk of breast cancer in Iranian patients. Thus, it may serve as a novel biomarker for identification of breast cancer tissues.