Clinical significance of miR-140-5p and miR-193b expression in patients with breast cancer and relationship to IGFBP5

• Autor(a) principal: Güllü,Gökçe
• Data de Publicação: 2015
• Outros Autores: Peker,Irem, Haholu,Aptullah, Eren,Fatih, Küçükodaci,Zafer, Güleç,Bülent, Baloglu,Hüseyin, Erzik,Can, Özer,Ayse, Akkiprik,Mustafa
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Genetics and Molecular Biology
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572015000100021
• topic: breast cancer; ER alpha; IGFBP5; micro RNA; miR-140; miR-193b

The functional role of IGFBP5 in breast cancer is complicated. Experimental and bioinformatics studies have shown that IGFBP5 is targeted by miR-140-5p and miR-193b, although this has not yet been proven in clinical samples. The aim of this study was to evaluate the expression of miR-140-5p and miR-193b in breast cancer and adjacent normal tissue and assess its correlation with IGFBP5 and the clinicopathological characteristics of the tumors. IGFBP5 protein expression was analyzed immunohistochemically and IGFBP5, miR-140 and miR-193b mRNA expression levels were analyzed with real-time RT-PCR. Tumor tissue had higher miR-140-5p expression than adjacent normal tissue (p = 0.015). Samples with no immunohistochemical staining for IGFBP5 showed increased miR-140-5p expression (p = 0.009). miR-140-5p expression was elevated in invasive ductal carcinomas (p = 0.002), whereas basal-like tumors had decreased expression of miR-140-5p compared to other tumors (p = 0.008). Lymph node-positive samples showed an approximately 13-fold increase in miR-140-5p expression compared to lymph node-negative tissue (p = 0.049). These findings suggest that miR-140-5p, but not miR-193b, could be an important determinant of IGFBP5 expression and clinical phenotype in breast cancer patients. Further studies are needed to clarify the expressional regulation of IGFBP5 by miR-140-5p.