Conditioned media from normal mammary cells induce mesenchymal changes in breast cancer cells. Effect of ionizing radiation

GUADALUPE VEDOYA, NORA MOHAMAD, TAMARA GALARZA, MÓNICA TÁQUEZ DELGADO, GRACIELA CRICCO, GABRIELA MARTIN

Congreso; LXI Reunión Científica Anual de la Sociedad Argentina de Investigación Clínica (SAIC); 2016

Conventional radiation therapy for breast cancer is delivered infractionated doses of 2 Gy post mastectomy or post conservativesurgery. Experimental evidence suggests that ionizing radiationmay promote migration and invasion of tumor surviving cells byintricate implications in the microenvironment and induction ofepithelial mesenchymal transition (EMT). We hypothesize thatcommunication between benign epithelial and neoplastic cellsincluded in the irradiated target volume may affect radiotherapyefficacy affecting local recurrences and metastasis. MCF10A cellswere used as a model of benign breast cells, while MDA-MB-231and MCF-7 as breast cancer cells. MCF10A cells were 2 Gyirradiated or not, incubated for 24 hours and then conditionedmedia were collected (2GyCM or CM). MDA-MB-231and MCF-7 cells irradiated (I) or not (NI) 􀁙ere incubated with 2GyCM or CMto evaluate clonogenicity, migration, gelatinolytic activity and EMTmolecular markers. Results showed that 2GyCM or CM􀀯 increasedclonogenic growth in I and NI MDA-MB-231 (p