PEFeffect on a 3D in vitro model: a breast cancer case

Pulsed electric fields are used to perform cell membrane electroporation. They are conveniently adopted in cancer therapy associated with chemotherapy, in order to improve the drug uptake maintaining the cell integrity (i.e. reversible electroporation RE), or alone, in order to destroy cells with an irreversible process (i.e. irreversible electroporation IRE). The RE therapy is currently used in Europe as an effective treatment of several types of superficially metastatic tumors like breast cancer recurrences. IRE is used in USA for cancer treatment. Recent studies put in evidence that electric stress can activate the immunological response of the cells. The 3D cultures realized by Hyaluronic acid scaffold functionalized with an adhesion sequence, allow the generation of the extracellular matrix, ECM, typical of the cell lines and enhance the cell cell and cell-ECM interactions. From previous studies, a different response in terms of electroporation intensity of the 3D and 2D cell cultures to the same protocol conditions was evidenced. Therefore, here we evaluated two breast cancer cell lines (MCF7 and MDA-MB-231) and established and validated their growth as 3D cell culture in Hyaluronic acid scaffolds. In these experimental condition, the cells were able to generate ECM with collagen and demonstrated an electroporation enhancement. In these models, the markers of reversible and irreversible electroporation will be evaluated and the results will be compared with 2D growth conditions. The 3D cultures will be exposed to different electroporation protocols, one typical of RE and IRE, in order to evaluate the stress response through PCR analyses of cytokine and inflammatory pathways.