Preparation and characterization of anionic PPI dendrimers for delivery of the hydroxychloroquine into tumor cells

• Autor(a) principal: Rodrigues, Ana Filipa Gonçalves
• Data de Publicação: 2022
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.13/4926
• topic: Dendrímeros PPI; Hidroxicloroquina; Libertação do fármaco; Citotoxicidade; Células MCF-7; Células CACO-2; Células BJ; PPI dendrimers; Hydroxychloroquine; Drug release; Cytotoxicity; MCF-7 cells; CACO-2 cells; BJ cells; Applied Biochemistry; .; Faculdade de Ciências Exatas e da Engenharia; Domínio/Área Científica::Ciências Naturais::Ciências Químicas; Domínio/Área Científica::Engenharia e Tecnologia::Engenharia Química; Domínio/Área Científica::Ciências Médicas::Biotecnologia Médica

Cancer is one of the most lethal diseases worldwide. In 2020, 19.3 million new cancer cases were reported, with approximately 10 million deaths. Female breast cancer was the most diagnosed, with 2.3 million new cases. Hydroxychloroquine (HCQ) is an immunomodulatory drug used to treat malaria and has been shown to have therapeutic potential in oncology. It has been proven that HCQ increases tumor cell death alone or combined with targeted agents or cytotoxic chemotherapy. By combining HCQ and a nanocarrier, it is possible to direct the drug to the tumor tissues, reducing the side effects and enhancing the bioavailability. Based on the previous experience of our group, the main goal of this master thesis was to prepare anionic carboxylate and sulfonate PPI dendrimers to transport and deliver the HCQ into tumor cells. First, amine-terminated PPI dendrimers, generation 0 to 3 (G0-G3), were synthesized, with a yield in the range of 57% -99%, and characterized by 1H- and 13C- NMR. After the G0 to G3 amine-terminated PPI dendrimers were prepared and obtained, the functionalization of the terminal groups with carboxylate and sulfonate dendrimers was done. Additionally, for the first time, the carboxylate- and sulfonate-terminated dendrimers G4 was synthesized. The anionic dendrimers have the advantage of being less cytotoxic, hemotoxic, and immunogenicity than cationic dendrimers. After G1 to G3 characterization by 1H 13C NMR, ATR-FTIR, DLS, zeta potential, and MS, HCQ was encapsulated. Following this, the in vitro drug release was performed in PBS with a pH 5 and 7.4, since the cumulative release is slightly higher in PBS with a pH 5. In general, all dendrimers showed a sustained release of HCQ in both pHs. The hemotoxicity of the dendrimers and the HCQ were also evaluated and showed no hemotoxicity. Finally, the cytotoxicity of the synthesized dendrimers, non-loaded and loaded with HCQ, was evaluated in a cancer cell line (MCF-7) and a non-cancer cell line (BJ cells). The HCQ in a range of concentration between 0.5 and 50 µM are highly cytotoxic for BJ cells and less cytotoxic for MCF-7 cells. The HCQ was further tested with the CACO-2 cells and showed to be less sensitive to the drug than with the MCF-7 cells. In order to improve the cytotoxicity of the prepared dendrimers, an assay with doxorubicin (DOX) was performed, but no synergetic effect was observed.