LAUSR

Metastases derived from primary tumors are responsible for the high cancer-associated death rates. Lymph nodes near to the primary breast tumor have a high chance to develop a secondary tumor, representing one of the first signs of metastasis. For this reason, inhibition of metastasis should be a major goal for breast cancer treatment. Metastasis is a non-random process that initiates with a phenotypic change of the tumor cells, named Epithelial-Mesenchymal Transition (EMT), and is leaded by the transcription factors SNAIL, SLUG, ZEB and TWIST. Because these changes in tumor cells must be plastic and reversible, epigenetic alterations are necessary for EMT. In this sense, microRNAs have emerged as candidate molecular biomarkers and novel therapeutic targets associated to metastasis. The aim of this study is to identify microRNAs that regulate the expression of EMT-transcription factors in breast cancer tumors, and that are involved in lymph node metastasis. For this purpose, we used microRNA microarray data from 50 fresh frozen breast tumors, 28 from patients with lymph node metastasis. Transcription factor expression was assayed by immunohistochemistry. Microarray data analysis using RankProd (R package) revealed approximately 40 microRNAs down-regulated in breast tumors expressing EMT-transcription factors (p Citation Format: Elisa Perez-Moreno, Valentina Zavala, Gabriela Valarezo, Wanda Fernandez, Pilar Carvallo. microRNAs targeting EMT transcription factors in breast cancer and their relation to lymph node metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2013.