Newly Synthesized CoFe2-xDyxO4 (x = 0; 0.1; 0.2; 0.4) Nanoparticles Reveal Promising Anticancer Activity against Melanoma (A375) and Breast Cancer (MCF-7) Cells

The current study focuses on the synthesis via combustion of dysprosium-doped cobalt ferrites that were subsequently physicochemically analyzed in terms of morphological and magnetic properties. Three types of doped nanoparticles were prepared containing different Dy substitutions and coated with HPGCD for higher dispersion properties and biocompatibility, and were later submitted to biological tests in order to reveal their potential anticancer utility. Experimental data obtained through FTIR, XRD, SEM and TEM confirmed the inclusion of Dy3+ ions in the nanoparticles' structure. The size of the newly formed nanoparticles ranged between 20 and 50 nm revealing an inverse proportional relationship with the Dy content. Magnetic studies conducted by VSM indicated a decrease in remanent and saturation mass magnetization, respectively, in Dy-doped nanoparticles in a direct proportionality with the Dy content; the decrease was further amplified by cyclodextrin complexation. Biological assessment in the presence/absence of red light revealed a significant cytotoxic activity in melanoma (A375) and breast (MCF-7) cancer cells, while healthy keratinocytes (HaCaT) remained generally unaffected, thus revealing adequate selectivity. The investigation of the underlying cytotoxic molecular mechanism revealed an apoptotic process as indicated by nuclear fragmentation and shrinkage, as well as by Western blot analysis of caspase 9, p53 and cyclin D1 proteins. The anticancer activity for all doped Co ferrites varied was in a direct correlation to their Dy content but without being affected by the red light irradiation.