RESUMO
BACKGROUND: Invasive ductal carcinoma (IDC) is the most frequent type of breast cancer (BC) in women, with a high clinical burden due to its high invasive properties. Despite of quickly emerging new data regarding the molecular heterogeneity of invasive cancers, far less is known about the molecular patterns among cases of IDC. An expanding body of evidence has demonstrated that dysregulation of long noncoding RNAs (lncRNAs) is involved in the heterogeneity feature of BC. METHODS: In this study, we analyzed the expression levels of two novel lncRNAs LOC100288637 and RP11-48B3 in 51 IDC tissues in comparison with adjacent non-cancerous tissues. And finally, bio-informatic evaluation has been done. RESULTS: The results of quantitative polymerase chain reaction showed that LOC100288637 and RP11-48B3 were significantly overexpressed in tumor tissues compared to normal samples (P = 0.0085 and P = 0.0002, respectively). Also, the two lncRNAs were overexpressed in both MDA-MB-231 and MCF-7 BC cell lines, nevertheless, with a higher expression pattern in MDA-MB-231 than MCF7 cell line. Furthermore, LOC100288637 had an elevated expression level in HER-2 positive tumors compared to HER-2 negative tumors (P = 0.031). Interestingly, the lncRNA RP11-48B3.4 was upregulated in IDC subjects with the age at menarche < 14 years compared to patients with the age at menarche 14 (P = 0.041). It was observed in another result that lncRNA RP11-48B3.4 is significantly upregulated in tumors with a lower histological grade compared to tumor samples with higher grades (P = 0.047). And finally, using bio-informatic evaluation, we found a predicted interaction between RP11-48B3.4 and mRNA zinc finger and BTB domain containing 10 (ZBTB10). CONCLUSION: Altogether, our findings suggest that these lncRNAs with potential oncogenic roles are involved in the pathogenesis of IDC with clinical significance and they may therefore serve as novel markers for the dia-gnosis and treatment of IDC.