br Fig summarizes the expression of different key
Fig. 6 summarizes the expression of different key genes and proteins involved in Nifurtimox signaling pathways, apoptosis and metastasis in MDA-MB-231 cells. Briefly, we suggested that these effects might be triggered upon binding of BthTX-II to some cell receptors such as the epidermal growth receptor, or to membrane phospholipids or integrins, in agreement to what previously reported [22,64,65]. Such binding on cell surface of TNBC cells would interfere PI3K-AKT pathway, responsible for cell survival and escape from apoptosis. The down-regulation of im-portant genes such as CDC25A, CCND1, CCNE1, E2F1 and TWIST1 as well as CK-5 and vimentin proteins could also provoke the inhibition of cell cycle, proliferation, invasion and metastasis, and the expression of the CDH-1 epithelial gene (E-cadherin) emphasizes the inhibition of the
metastatic phenotype, reducing the aggressiveness of TNBC. However, despite the relevance of our findings, the discovery of the BthTX-II tar-get in MDA-MB-231 cells and full elucidation of the BthTX-II mecha-nisms require further investigations that will be the focus of future studies.
In summary, the present work shed light on BthTX-II antitumor and antimetastatic effects on MDA-MB-231. BthTX-II induced cell death, in-hibition cell proliferation, adhesion, migration, invasion and 3D growth, reducing the aggressiveness of TNBC cell line. Besides, BthTX-II de-creased vimentin, TWIST1, CK-5 and increased E-cadherin (CDH-1) ex-pression leading MDA-MB-231 cells to assume a more epithelial phenotype. Finally, since BthTX-II showed a remarkable efficacy against the EMT and metastatic processes, we propose that this PLA2 may be a potential model for drug design that aims to develop innovative antitu-moral therapies against TNBC.
Supplementary data to this article can be found online at https://doi.
Declaration of Competing Interest
All authors read and agreed to the manuscript content, approved the submission and stated that there was no conflict of interest.
The CAPES, FAPEMIG and CNPq supported this work and the authors gratefully acknowledge the financial support of the Brazilian Funding Agencies.
The authors thank Federal University of Uberlandia (UFU), Brazil and the Brazilian funding agencies, CNPq, CAPES and FAPEMIG, for providing financial support to this study: FAPEMIG (CBB-APQ-01637-15); FAPEMIG (CBB - APQ-01401-17) and National Institute of Science and Technology in Theranostics and Nanobiotechnology INCT-TeraNano-CNPq/CAPES/FAPEMIG, Grant numbers CNPq-465669/2014-0.
F.V.P.V.A, D.S.L, S.N.C.G, performed the cytotoxicity and immune re-sponse assays. F.V.P.V.A, P.T.A, D.S.L, S.N.C.G., performed qPCR analysis. F.V.P.V.A, V.M.R.A, L.R.G; conceived the concept and the experimental design. L.V.; M.A.P.Z; performed the flow cytometer analysis, western blot and microscopy analyses. R.S.R., K.A.G.Y., A.C.AS. collaborated with the creation and formatting of figures.
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