Citotoxicidade dos extratos de Kalanchoe brasiliensis e Achyrocline satureoides a linhagens celulares de câncer de mama

Abstract

Breast Cancer (BC) is the most commonly diagnosed malignant tumor in women worldwide, being one of the main causes of cancer death among them. Breast tumors, in addition to being classified histologically, are also characterized molecularly according to the expression of hormone receptors (estrogen and progesterone) and Human Epidermal Growth Factor Receptor 2 (HER2). Triple Negative BC (TNBC) does not express any of the three markers, it is the most aggressive and has the worst prognosis due to its heterogeneity and therapeutic limitations. Chemotherapy remains widely used, but not very selective and responsible for debilitating side effects. In this context, the search for new compounds is imperative and natural products have shown promise in view of their pharmacological potential and reduced toxicity to normal cells. The present study aimed to evaluate the cytotoxicity of the hydromethanolic extract of the plant species Kalanchoe brasiliensis and of the methanolic extract of Achyrocline satureioides in different cell lines of BC (T47D and MCF-7 – luminal; MDA-MB453 – HER2+; MDA-MB157 and MDA-MB231 – TN) by means of the MTT assay. The MCF-10A strain (non-tumorigenic) was used as a control. For K. brasiliensis, the MDA-MB231 strain had its viability reduced by more than 50% after 24 and 48 hours, with IC50 = 218.00 and IC50 = 311.00µg/mL, respectively. However, the extract was selective only when this strain was treated for 48 hours. For A. satureoides, the non-tumorigenic strain was more sensitive, being significantly cytotoxic at initial concentrations. For tumor cell lines, the extract was more selective for MCF-7 after 48 hours, with IS = 1.91. Therefore, the BC cells showed a different behavior for the two plant extracts, with K. brasiliensis being promising for one of the TNs strains. However, further studies are needed to understand the mechanisms of action of the compounds present in this hydromethanolic extract to inhibit the progression of TNBC.