CHARACTERIZATION OF NOVEL MURINE MAMMARY CELL LINES WITH DIFFERENT AGGRESSIVE PHENOTYPE AND IDENTIFICATION OF POTENTIAL TARGETS BY MASS SPECTROMETRY

SIDABRA, JOHANNA ELENA; CAPOBIANCO, CARLA SABRINA; GOTTARDO, MARÍA FLORENCIA; ALONSO, DANIEL; FARINA, HERNAN GABRIEL

Congreso; LXIV REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACIONES CLÍNICAS; 2019

Breast cancer is the first cause of deathfrom female cancer. After the treatments against the primarytumour, a few cells can remain in a state of quiescence for a longperiod, becoming undetectable. These cells can resume growthand establish as metastasis, which are responsible for 90 % ofdeaths from cancer. In a previous work, we isolated andcharacterized two cell lines, F3II-TP and F3II-NM. F3II-TPrepresents tumours with high proliferation rate whereas F3II-NMrepresents a quiescent cell phenotype. The comparison betweenthese cell lines is expected to yield new molecular targets forboth the design of antiproliferative drugs as well as drugs thatpoint quiescent cells. The aim of this work was to continue withthe characterization of these cell lines and identify possibletargets. First, we analysed the expression of EMT markers suchas E-cadherin, N-cadherin, Vimentin, Pan-Cytoqueratin and βcatenin by immunofluorescence. We determinated that F3II NMhas a mesenchymal phenotype and F3II TP an undifferentiatedone. In addition, the expression of the dormancy related geneNR2F1 was analysed by qPCR and we found that F3II-NM showedhigher levels of transcript than F3II-TP. Furthermore, in anorthotopic model of BALB/c mice, F3II NM presented a longerlatency time and lower tumour growth rate in comparison toF3II-TP. Finally, analysis of the cell lines using LFQ-Massspectrometry revealed 256 differentially expressed genesbetween the three lines studied. Overexpressed genes of survivalpaths were identified in F3II-NM, such as DDX42, COX-2,Aldh3a2 involved in the inhibition of apoptosis, promotion oftumour recurrence via SOX-2 and therapy resistance,respectively; and in F3II-TP, proliferation related genes wereidentify such as Flnb, Aldoa, G6pdx, involved in actincytoskeleton reorganization and in cellular metabolism. Toconclude, these results contribute to the characterization of bothnew cell lines and to the identification of new molecular targets.