In vitro anti-cancer activity of fungal proteins adsorbed on silica nanoparticles

ROCHA GABRIELA; MITAROTONDA R; DESIMONE, MARTÍN; FUSCO MARIEL; DIAZ ME

CABA

Jornada; Jornada de la Sociedad Argentina de Biología; 2018

Sociedad Argentina de Biología

The anticancer treatments that are currently used have a high toxicity due to the lack of specificity, since they affect tumor cells and healthy cells. Therefore, research in this field focuses on the discovery of new drugs obtained from natural sources that selectively kill cancer cell and new tools like nanoparticles that could increase stability and could be used as delivery system to targeted organs or cells. The aim of this work was to evaluate the cytotoxic capacity on cancer cells of fungal proteins adsorbed on silica nanoparticles (SiO2NPs). In order to achieve this goal, an extract rich in proteins of the edible mushroom Agaricus bisporus was obtained by extraction with 5% acetic acid followed by ethanolic precipitation. The proteins presents in the extract were separated by size-exclusion liquid chromatography (SEC-FPLC). Besides, negative nanoparticles were synthesized by the Stöber method and characterized by TEM, DLS, and potential Z. The SiO2NPs obtained were homogeneous population and had a size of 80.0 ± 5.7 nm. The protein fraction (PF) was incubated with the nanoparticles at 500 rpm and 4 ° C for 6 h to allow the adsorption of the proteins on the SiO2NPs.. After incubation, it was obtained that the adsorption capacity of proteins was 5-15μg/0.05 mg NPs (determined by SDS-PAGE and Bradford method). The adsorption of the proteins on the nanoparticles (SiO2NPs-PF) remained stable during at least 20 days. The cytotoxic capacity of the proteins and SiO2NPs-PF was evaluated on MCF-7 cells and PBMC human cells by a colorimetric test using 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide. In addition, the cytokines and growth factors levels were evaluated by ELISA (IL-1β, IL-6, TGF-β). The results showed that one PF had antitumor activity with high cytotoxicity against MCF-7 cells (82%). We obtained that the PF was nontoxic on this cells (7.3%) and cytokine levels did not present significant differences with control. Moreover, SiO2NPs-PF had a higher antitumor action on MCF-7 cells (94%) and did not affect human red blood cells (0.6-2.1% hemolysis) or PBMC cells. These results allow us to continue with the studies in the search for new chemotherapeutic treatments and tools that improve the specificity and bioavailability for the fight against cancer.