Synthesis, cytotoxicity and antitumour mechanism investigations of polyoxometalate doped silica nanospheres on breast cancer MCF-7 cells

Abstract

Polyoxometalates (POMs) have shown the potential anti-bacterial, anti-viral and anti-tumor activities. In order to improve their physiological stability and antitumour activity for medical application, K2Na[AsIIIMo6O21(O2CCH2NH3)3]·6H2O doped silica nanospheres (POM@SiO2) with diameters of ~40 nm have been synthesized by the water-in-oil microemulsion method in this study. The obtained spheres were morphologically uniform nanosized and nearly monodispersed in solution. The nanoparticles had high entrapment efficiency, which was upto 46.2% by the inductively coupled plasma mass spectrometry (ICP-MS) analysis and POMs slowly released from the nanospheres both in the PH 7.4 and 5.5 phosphate buffer saline (PBS) solutions in 60 h. The in vitro MTT assays of particles on MCF-7 cell line (a human breast adenocarcinoma cell line) exhibited enhanced antitumor activity compared to that of plain polyoxometalate. The IC50 value of the POM@SiO2 nanoparticles was 40.0 μg/mL at 24 h calculated by the encapsulated POM concentration, which was much lower comparing to that of 2.0 × 104 μg/mL according to the pure POM. And the SiO2 shells showed low inhibitory effect at the corresponding concentration. Confocal images further indicated the cell morphology changes and necrosis. Flow cytometric analysis showed nanoparticles induced the apoptosis by arresting the cells in S phase and western blot analysis indicated they promoted apoptosis by inhibiting the Bcl-2 protein. Moreover, the study of interactions between human serum albumin (HSA) and the nanoparticles indicated the fluorescence quenching was static, and the nanoparticles were likely to bind to HSA and changed its conformation.

Optimized Polyethylene Glycolylated Polymer–Lipid Hybrid Nanoparticles as a Potential Breast Cancer Treatment

“…Figure 6 c shows an increase in the nuclear fluorescence intensity after 72 h of cells treated with ANS-PLNPs and PEG-ANS-PLNPs as compared with the intensity at time 0. This points towards the presence of a significant population of DNA-damage related cell death due to the release of the ANS from the PLNP [ 48 , 49 ].…”

Green synthesis of silver nanoparticles via Cynara scolymus leaf extracts: The characterization, anticancer potential with photodynamic therapy in MCF7 cells

“…The formation of Ag nanoparticles was observed [27] by Ultraviolet-visible (UV-Vis) spectrophotometer (Thermo Scientific Multiscan Spectrum 1500, USA) with a range of 200–800 nm. The functional groups on AgNPs were validated with Fourier-transform infrared (FTIR) spectroscopy using in the range of 400–4000 cm -1 (Shimadzu IR 8000, Japan).…”

“…Propidium iodide (PI) and Hoechst 33342 double staining [27, 29] in cultured MCF7 cells were measured to detect apoptosis after the treatment of AgNPs with PDT. Cells (1 × 10 5 ) were cultured in a six-well plate and treated with different concentrations of AgNPs then eight hours incubated with PDT exposed cells.…”

In vivo toxicity evaluation of two polyoxotungstates with potential antidiabetic activity using Wistar rats as a model system

“…W 6+ , V 5+ ). Earlier studies showed that these inorganic drug candidates possess potential anti-viral, [10][11][12] -bacterial, 13,14 -protozoal, 15 -tumor, 16,17 -Alzheimer 18 and -diabetic activities. 8,9 However, their molecular modes of action are poorly understood.…”