Polymeric nanoparticles promote endocytosis of a survivin molecular beacon: Localization and fate of nanoparticles and beacon in human A549 cells

Publication date: Available online 7 November 2018Source: Life SciencesAuthor(s): Barbara Adinolfi, Mario Pellegrino, Sara Tombelli, Cosimo Trono, Ambra Giannetti, Claudio Domenici, Greta Varchi, Giovanna Sotgiu, Marco Ballestri, Francesco BaldiniAbstractPolymethylmethacrylate core-shell fluorescent nanoparticles promote, in human lung A549 cancer cells, the internalization of a molecular beacon (MB) specific for survivin mRNA, an anti-apoptotic protein overexpressed in cancer cells.AimsTo design an effective drug delivery system, the knowledge of the uptake mechanism and of the nanoparticles (NPs) and MB fate is required.Materials and methods and key findingsExperiments with dextran as marker for endocytosis showed that in the presence of NPs the number of endocytic vesicles per cell doubled and their mean size significantly (p < 0.001) increased with respect to controls in absence of NPs, indicating an involvement of NPs in the endocytotic process.By using LysoTracker™ Deep Red, as marker of lysosomes, we found that nanoparticles co-localize with lysosomes. Moreover, a cellular release of nanoparticles detected in the culture medium, suggested a role of lysosomal exocytosis in nanoparticle elimination. The MB fluorescence in proximity of the labeled Endoplasmic Reticulum was indicative that the opening of the MB occurs in proximity of its target mRNA.SignificanceThe results show the involvement of endocytotic pathway in the uptake of NPs, which are an appropriate ...
Source: Life Sciences - Category: Biology Source Type: research