en Molecular Genetics & Genomics Molecular Genetics & Genomics مقاله کامل Full Length/Original Article <strong>Background:</strong> Despite recent advances in diagnosis and treatment, breast cancer remains a leading cause of death in women worldwide. Long non-coding RNAs are a new class of RNA molecules that have been shown to participate in tumorigenesis. The aim of this study was to investigate the expression of lncUSMycN in tumor samples and to evaluate its potential role in the breast cancer cell line. <strong>Methods</strong>: Real-time polymerase chain reaction was employed to assess lncUSMycN expression in breast tumor tissues and cancer cell lines. Furthermore, small interfering RNA was used to knockdown lncUSMycN. <strong>Results:</strong> The data showed the significant up-regulation of lncUSMycN in tumor tissues compared to non-tumor specimens (95% CI, <em>p</em> = 0.002). Receiver operating characteristic (ROC) curve analysis demonstrated the biomarker potential of lncUSMycN (ROCAUC = 0.70, <em>p</em> < 0.001) for invasive breast ductal carcinoma. Furthermore, lncUSMycN knockdown induced apoptosis and suppressed cellular migration in breast cancer cells (<em>p</em> < 0.01).<strong> Conclusion:</strong> The findings highlight the pivotal role of lncUSMycN in tumorigenesis, providing a new potential target for breast cancer therapy.&nbsp; Breast cancer, Real-time polymerase chain reaction, siRNA 303 311 http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-1-778&slc_lang=en&sid=1 Reyhaneh Ravanbakhsh Gavgani 0000-0002-9644-6204 No Department of Biological Sciences, School of Natural Sciences, University of Tabriz, Tabriz, Iran Esmaeil Babaei 0000-0002-1603-5166 Yes Department of Biological Sciences, School of Natural Sciences, University of Tabriz, Tabriz, Iran Mohammad Ali Hosseinpourfeizi No Department of Biological Sciences, School of Natural Sciences, University of Tabriz, Tabriz, Iran Ashraf Fakhrjou No Department of Pathology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran Vahid Montazeri No Department of Thoracic Surgery, Noor-Nejat Hospital, Tabriz, Iran