Cinzia Della Giovampaola1, Antonietta Capone1, Leonardo Ermini2, Pietro Lupetti1, Elisa Vannuccini1, Federica Finetti1, Sandra Donnini1, Marina Ziche1, Agnese Magnani3, Gemma Leone3, Claudio Rossi4, Floriana Rosati1, Claudia Bonechi5. 1. Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy. 2. Department of Life Sciences, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; Program in Physiology & Experimental Biology, Hospital for Sick Children, Toronto, Canada. 3. Department of Biotechnology, Chemistry, and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; INSTM, Research Center for Materials Sciences and Technologies, Via G. Giusti 9, 50121 Firenze, Italy. 4. Department of Biotechnology, Chemistry, and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; CSGI, Research Center for Colloids and Nanoscience, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, FI, Italy. 5. Department of Biotechnology, Chemistry, and Pharmacy, University of Siena, Via Aldo Moro 2, 53100 Siena, Italy; CSGI, Research Center for Colloids and Nanoscience, University of Florence, Via della Lastruccia 3, 50019 Sesto Fiorentino, FI, Italy. Electronic address: claudia.bonechi@unisi.it.
Abstract
BACKGROUND: Liposomes, used to improve the therapeutic index of new and established drugs, have advanced with the insertion of active targeting. The lectin from Lotus tetragonolobus (LTL), which binds glycans containing alpha-1,2-linked fucose, reveals surface regionalized glycoepitopes in highly proliferative cells not detectable in normally growing cells. In contrast, other lectins localize the corresponding glycoepitopes all over the cell surface. LTL also proved able to penetrate the cells by an unconventional uptake mechanism. METHODS: We used confocal laser microscopy to detect and localize LTL-positive glycoepitopes and lectin uptake in two cancer cell lines. We then constructed doxorubicin-loaded liposomes functionalized with LTL. Intracellular delivery of the drug was determined in vitro and in vivo by confocal and electron microscopy. RESULTS: We confirmed the specific localization of Lotus binding sites and the lectin uptake mechanism in the two cell lines and determined that LTL-functionalized liposomes loaded with doxorubicin greatly increased intracellular delivery of the drug, compared to unmodified doxorubicin-loaded liposomes. The LTL-Dox-L mechanism of entry and drug delivery was different to that of Dox-L and other liposomal preparations. LTL-Dox-L entered the cells one by one in tiny tubules that never fused with lysosomes. LTL-Dox-L injected in mice with melanoma specifically delivered loaded Dox to the cytoplasm of tumor cells. CONCLUSIONS: Liposome functionalization with LTL promises to broaden the therapeutic potential of liposomal doxorubicin treatment, decreasing non-specific toxicity. GENERAL SIGNIFICANCE: Doxorubicin-LTL functionalized liposomes promise to be useful in the development of new cancer chemotherapy protocols.
BACKGROUND: Liposomes, used to improve the therapeutic index of new and established drugs, have advanced with the insertion of active targeting. The lectin from Lotus tetragonolobus (LTL), which binds glycans containing alpha-1,2-linked fucose, reveals surface regionalized glycoepitopes in highly proliferative cells not detectable in normally growing cells. In contrast, other lectins localize the corresponding glycoepitopes all over the cell surface. LTL also proved able to penetrate the cells by an unconventional uptake mechanism. METHODS: We used confocal laser microscopy to detect and localize LTL-positive glycoepitopes and lectin uptake in two cancer cell lines. We then constructed doxorubicin-loaded liposomes functionalized with LTL. Intracellular delivery of the drug was determined in vitro and in vivo by confocal and electron microscopy. RESULTS: We confirmed the specific localization of Lotus binding sites and the lectin uptake mechanism in the two cell lines and determined that LTL-functionalized liposomes loaded with doxorubicin greatly increased intracellular delivery of the drug, compared to unmodified doxorubicin-loaded liposomes. The LTL-Dox-L mechanism of entry and drug delivery was different to that of Dox-L and other liposomal preparations. LTL-Dox-L entered the cells one by one in tiny tubules that never fused with lysosomes. LTL-Dox-L injected in mice with melanoma specifically delivered loaded Dox to the cytoplasm of tumor cells. CONCLUSIONS: Liposome functionalization with LTL promises to broaden the therapeutic potential of liposomal doxorubicin treatment, decreasing non-specific toxicity. GENERAL SIGNIFICANCE: Doxorubicin-LTL functionalized liposomes promise to be useful in the development of new cancer chemotherapy protocols.
Authors: Harshita Mishra; Pawan K Mishra; Adam Ekielski; Manu Jaggi; Zeenat Iqbal; Sushama Talegaonkar Journal: J Cancer Res Clin Oncol Date: 2018-08-09 Impact factor: 4.553