RESUMO
Recent discovery showing the presence of microRNAs (miRNAs) in the circulation sparked interest in their use as potential biomarkers. Our previous studies showed the diagnostic potential of miR-451 as a serological marker for inflammatory breast cancer (IBC), miR-337- 5p and miR-30b for non-inflammatory breast cancer (non-IBC). The aim of this study is to investigate the prognostic values of circulating miRNAs by comparing the amounts of 12 circulating miRNAs in the serum of IBC and non-IBC from Tunisian breast cancer patients, and by determinating whether correlated pairs of miRNAs could provide useful information in the diagnosis of IBC and non-IBC patients. TaqMan qPCR was performed to detect circulating expression of miRNAs in serum of 20 IBC, 20 non-IBC and 20 healthy controls. Nonparametric rank Spearman rho correlation coefficient was used to examine the prognostic value of miRNAs and to assess the correlation profile between miRNAs expression. Further, a large number of miRNAs were highly correlated (rho>0.5) in both patients groups and controls. Also, the correlations profiles were different between IBC, non-IBC and healthy controls indicating important changes in molecular pathways in cancer cells. Our results showed that miR-335 was significantly overexpressed in premenopausal non-IBC patients; miR-24 was significantly overexpressed in non-IBC postmenopausal patients. Patients with previous parity had higher serum of miR-342-5p levels than those without. Furthermore, patients with HER2+ IBC present lower serum levels of miR-15a than patients with HER2- disease. Together, these results underline the potential of miRNAs to function as diagnostic and prognostic markers for IBC and non-IBC, with links to the menopausal state, Her2 status and parity.