Caracterização da expressão de Anexina A2 e Citoqueratina 10 em modelos celulares de Câncer de Mama

Abstract

Breast cancer (BC) is the most common malignant tumor and the leading cause of cancer death among women worldwide. The complexity of BC translates into different clinical behaviors of its subtypes, especially the triple negative one (TNBC). The molecular events of these tumors remain unknown, which hinders the development of target therapies that improve the patient’s survival. In the present study, using flow cytometry and western-blotting techniques, the aim was to evaluate the expression profile of the proteins Annexin A2 (AnxA2) and Cytokeratin 10 (Ck10) in the MCF10A (non-tumorigenic), MCF7 (luminal phenotype) and MDA-B231 (triple-negative phenotype) cell lines. High expression of both proteins was observed in the MCF10A and MDA-MB231 strains by flow cytometry. Interestingly, when the cellular proteins were extracted in fractionated way (cytoplasm/membrane separated from the nucleus), the staining was distinct between the cell lines, the protein fractions, and the targets. AnxA2 was less expressed in MCF7 cell line in the two fractions analyzed. Considering Ck10, there was no difference in the staining for nuclear proteins. However, the expression of this protein was lower in the cytoplasm/membrane fraction for the luminal lineage, suggesting a peculiar behavior in triple-negative cells. No staining was identified in the culture supernatant. The absence of specific markers for TNBC highlights the importance of understanding the expression profile and behavior of AnxA2 and Ck10 in these tumors. Our results will drive new approaches for this tumor subtype and will contribute to a more detailed classification of TNBC, which lacks more effective treatment strategies.