Dados do Trabalho

Título

BthTX-II from Bothrops pauloensis snake venom: Unveiling Its Antitumor, inhibition of Epithelial-Mesenchymal Transition and Antiangiogenic Properties in Breast Tumor Cells

Introdução

Phospholipases A2 (PLA2) are widely distributed enzymes with diverse pharmacological activities and therapeutic potential.

Objetivo (s)

This study investigates the effects of BthTX-II, a specific variant of PLA2 (Asp49) isolated from Bothrops jararacussu venom, on breast cancer cells, focusing on its antitumor, antimetastatic, and antiangiogenic properties through in vitro, ex vivo and in vivo approaches.

Material e Métodos

In vitro analyses were performed on MDA-MB-231 and HUVEC cells in 2D and 3D models. The cells were treated with varying concentrations of BthTX-II for different durations. Pathway death and cycle cell assays were conducted using flow cytometry and confocal microscopy, while gene and protein expression were evaluated through RNA and protein extraction. Endothelial and vascular growth factor levels were measured in the cell culture supernatant. Ex vivo assay was obtained by incubating aortic fragments from mice in Matrigel with BthTX-II. In vivo experiment, MDA-MB-231 cells were inoculated into the chorioallantoic membrane of chicken embryos and treated with BthTX-II at different concentrations. Tumor progression was assessed after 96 hours of treatment.

Resultados e Conclusão

BthTX-II was found to induce cell death by modulating key genes in the intrinsic and extrinsic signaling pathways. It effectively inhibited proliferation, adhesion, migration, invasion, and 3D growth in matrigel, thereby reducing the aggressiveness of metastatic breast cancer cells. The negative modulation of tumor suppression genes BRCA1 and BRCA2 played a role in this inhibition. Furthermore, BthTX-II downregulated the expression of vimentin, TWIST1, and CK-5, while increasing the protein expression of E-cadherin. These molecular changes resulted in a distinctive epithelial phenotype in metastatic breast cancer cells by reduced invasiveness. Notably, BthTX-II exhibited inhibitory effects on human endothelial cell adhesion, invasion, and migration, effectively blocking angiogenesis. This was demonstrated by reduced vessel formation in HUVEC cells in vitro and suppression of cell extensions in an ex vivo aortic fragment model. Additionally, BthTX-II showed a significant reduction in tumor mass in vivo as observed in the membrane assay using chicken embryos. These findings highlight the antitumor and antiangiogenic activities of BthTX-II, positioning it as a promising prototype for the development of novel antitumor drugs, particularly for triple-negative breast cancer therapy.

Palavras-chave

PLA2, breast cancer, snake venom

Agradecimentos

INCT-TeraNano