BioProject

Breast cancer is the most common malignancy that develops in women, responsible for the highest cancer-associated death rates. More...

Breast cancer is the most common malignancy that develops in women, responsible for the highest cancer-associated death rates. Triple negative breast cancers (TNBC) represent an important subtype that have an aggressive clinical phenotype, are associated with a higher likelihood of metastasis and are not responsive to current targeted therapies. miRNAs have emerged as an attractive candidate for molecular biomarkers and treatment targets in breast cancer, but their role in the progression of TNBC remains largely unexplored. This study has investigated miRNA expression profiles in 31 primary TNBC cases and in 13 lymph node metastases compared with 23 matched normal breast tissues to determine miRNAs associated with the initiation of this disease subtype and those associated with its metastasis. 71 miRNAs were differentially expressed in TNBC, the majority of which have previously been associated with breast cancer, including members of the miR-200 family and the miR-17-92 oncogenic cluster, suggesting that miRNAs involved in the initiation of TNBC are not subtype specific. However, the repertoire of miRNAs expressed in lymph node negative and lymph node positive TNBCs were largely distinct from one another. In particular, miRNA profiles associated with lymph node negative disease tended to be up-regulated, while those associated with lymph node positive disease were down-regulated and largely overlapped with the profiles of their matched lymph node metastases. Overall design: miRNA expression profiles were examined in 31 primary TNBC cases and in 13 lymph node metastases compared with 23 matched normal breast tissues Less...