Investigating the effects of drug-loaded nanoparticles on the cellular behavior of proliferative diseases

A common feature of nanoparticles (NPs) is their large surface area to volume ratio that makes them an attractive tools for the development of drug delivery systems, improving several properties of ‘‘free’’ drugs: solubility, pharmacokinetic profile and biodistribution. During my PhD, I studied different nanovehicles loaded with “free” hydrophobic drugs against three “over-proliferative” diseases to evaluate the efficacy and safety of nanodrugs. In the first year, I focused the anti-proliferative effect of ASC-J9, a promise in the treatment of prostate cancer. ASC-J9 is a very hydrophobic molecule, which limits drug administration. ASC-J9 was loaded on PLGA NPs, in order to improve the solubility of the molecule and applied to an estrogen-dependent breast cancer. My results showed a cellular growth inhibition associated with a specific G2/M cell cycle block, which led to apoptosis. In the second year, I worked in collaboration with group of IRCCS San Matteo (PV). In a previous work (2014), Cova et al evaluated the effectiveness of gold NPs functionalized with anti-CD44 monoclonal antibody loaded with everolimus (GNP-HCe), prepared by our laboratory, in inhibiting mesenchymal cells (MCs), the primarily responsible for the bronchiolitis obliterans syndrome (BOS). Considering that BOS is due to an alteration of inflammatory process the aim is determined the effect of GNP-HCe on macrophages, neutrophils and lymphocytes with in vitro assays assessing cytokine secretion, cell apoptosis and ROS production. Next, we administered GNP-HCe by aerosolization in normal mice evaluating the localization and toxicity on lungs and peripheral organs. GNP-HCe were able to reduce ROS and not to enhance the activity of three major components of immune response. The in vivo experiments confirmed that inhaled NPs did not raise the inflammatory response, because the bronchoalveolar lavage of mice did not show significant increase of IL-8 cytokine. This study discloses the possibility to plan a new pharmacological treatment for patients affected by pulmonary fibroproliferative disorders directly targeting MCs without altering the immune response. During the last year, I focused on triple negative breast cancer (TNBC) representing only the 15% of breast cancers, but the most aggressive phenotype. TNBCs lack three specific molecular markers (ER, PR and HER-2), which makes the current chemotherapeutic approaches mostly ineffective. TNBC cells show strong drug resistance due to the overexpression of P-glycoprotein (Pgp), MDR-associated proteins (MRP1), and breast cancer resistance protein (BCRP) that actively efflux the drug outside the cells conferring resistance to treatment. Curcumin possesses a wide range of pharmacological activities; one is the capacity to modulate the MDR activity in different type of cancer cells, affecting the expression and the functionality of MDR proteins. There are no data in literature on TNBC cells, so, we aim to evaluate modulation of Pgp, MRP1 and BCRP expression and their functionality in two different TNBC cell lines (MDA-MB-468 and MDA-MB-231) after treatment with curcumin. One of the problems is the lipophilic nature of this molecule; thus, to improve the drug solubility, we encapsulated curcumin inside H-ferritin nanocages (HFn). We have demonstrated that HFn recognize transferrin receptor 1 (TfR1), overexpressed by TNBC cells, with high binding capacity. The HFn-TfR1 interaction mediates the internalization of HFn, which disassembles into subunits inside the cytoplasm, allowing the intracellular release of drugs. Work is in progress to assess the effect of HFn-curcumin on TNBCs