Abstract 1478: Curcumin inhibits epithelial-mesenchymal transition and invasion in breast cancer cells by controlling miR-34a expression

Abstract Breast cancer in advanced stages tends to develop metastases and / or chemoresistance, in both cases therapeutic options are limited and have low probability of success, which represents the biggest obstacle in reducing mortality from this disease. There is a close connection between the Epithelial-Mesenchymal Transition (EMT) process of cancer cells and the acquisition of invasive and metastatic ability. Numerous EMT mediators have been described in cancer and among them miRNAs play a fundamental role in regulating such process, suggesting that it could be a therapeutic target to address this phenotype. Curcumin (diferuloylmethane) is a derivative compound of Curcuma longa that has therapeutic properties in various cancers as blocking initiation and tumor progression through its anti-inflammatory, antioxidant, proapoptotic, antiangiogenic and antimetastatic effects. The role of curcumin on EMT in non-cancerous breast cells MCF-10F and in breast cancer cell lines MCF-7 and MDA-MB-231 was evaluated. This work shows that in all these cell lines curcumin induced the expression of tumor suppressor microRNA miR-34a and repressed the expression of several genes involved in EMT and metastasis as Axl, Slug, Twist, N-cadherin, vimentin, fibronectin, among others. Consequently, curcumin inhibited the migration and invasiveness in these cells, irrespective of the expression of estrogen and progesterone receptors and p53 mutational status. Blockade of miR-34a by transfection with antagomiR-34a inhibited the effect of curcumin on EMT genes and on the migratory/invasive potential of cells indicating that miR-34a plays a central role in the Curcumin-mediated suppression of EMT and invasion. Therefore, results confirm the suppressive effect of curcumin on EMT and invasion in breast cancer cells, showing that such substance exerts this effect by inducing expression of miRNA miR-34a and consequently the repression of several of its target genes. Supported by Tarapacá University, Arica, Chile (GMC). Citation Format: Marcela Gallardo, Richard Ponce-Cusi, Gloria M. Calaf. Curcumin inhibits epithelial-mesenchymal transition and invasion in breast cancer cells by controlling miR-34a expression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1478. doi:10.1158/1538-7445.AM2017-1478