Early apoptosis induction in MCF-7 breast cancer cells by bacterial exopolysaccharide-coated magnetic iron oxide nanoparticles

Abstract

As breast cancer is the most widespread female malignancy, innovative and safe synergistic anticancer strategies are needed, particularly to improve drug delivery to the tumor. One of the important aspects of cancer targeting is apoptosis induction, which is the main purpose of this study. Exopolysaccharide (EPS) extracted from Streptococcus mutans and magnetic iron oxide nanoparticles-coated EPS (EPS/MIONS) effects on MCF-7 and MCF-10A were studied. MIONS was synthesized by co-deposition method and characterized by TEM and XRD; its surface was coated with EPS, checked by FT-IR. MTT assay, AO/EB staining, and flow cytometry analysis were performed to assess the MCF-7 cells viability at various EPS/MIONS and EPS concentrations, as well as to determine apoptosis. The levels of superoxide dismutase (SOD), catalase (CAT), also malondialdehyde (MDA) enzymes were determined. The XRD and FT-IR spectrum confirmed the MIONS purity and chemical integration of EPS/MIONS. The EPS and EPS/MIONS significantly reduced the MCF-7 cell viability without showing toxicity on MCF-10A cells. The most effective dose (IC50) was 250 mu g/mL EPS/MIONS after 48 h. According to flow cytometry studies, the percentages of early and late apoptotic cells were equal to 71.87 f 1.25 and 21.7 f 2 for EPS/ MIONS, and 59.09 f 5 and 39.95 f 1 for EPS. The SOD and CAT levels were increased in the presence of EPS and EPS/MIONS groups compared to the control (pValue<0.05). However, the MDA levels significantly decreased. The EPS/MIONS found to be superior in apoptosis induction, morphological alterations, and cell growth suppression. This research emphasizes the importance of EPS, its conjugation with MIONS, and their potential as novel anticancer-promising agents.