Itraconazole (ITC), a well-tolerated antifungal drug, exerts multiple anticancer effects which justified its preclinical and clinical investigation as potential anti-cancer agent with reduced side effects. Enhancement of ITC anti-cancer efficacy would bring valuable benefits to patients. We propose herein lipid nanocapsules (LNCs) modified with a subtherapeutic dose of miltefosine (MFS) as a membrane bioactive amphiphilic additive (M-ITC-LNC) for the development of an ITC nanoformulation with enhanced anticancer activity compared with ITC solution (ITC-sol) and unmodified ITC-LNC. Both LNC formulations showed a relatively small size (43–46 nm) and high entrapment efficiency (>97%), though ITC release was more sustained by M-ITC-LNC. Cytotoxicity studies revealed significantly greater anticancer activity and selectivity of M-ITC-LNC for MCF-7 breast cancer cells compared with ITC-sol and ITC-LNC. This trend was substantiated by in vivo findings following a 14 day-treatment of murine mammary pad Ehrlich tumors. M-ITC-LNC showed the greatest enhancement of the ITC-induced tumor growth inhibition, proliferation, and necrosis. At the molecular level, the tumor content of Gli 1, caspase-3, and vascular endothelial growth factor verified superiority of M-ITC-LNC in enhancing the ITC antiangiogenic, apoptotic, and Hedgehog pathway inhibitory effects. Finally, histopathological and biochemical analysis indicated greater reduction of ITC systemic toxicity by M-ITC-LNC. Superior performance of M-ITC-LNC was attributed to the effect of MFS on the structural and release properties of LNC coupled with its distinct bioactivities. In conclusion, MFS-modified LNC provides a simple nanoplatform integrating the potentials of LNC and MFS for enhancing the chemotherapeutic efficacy of ITC and possibly other oncology drugs.

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Itraconazole (ITC), an antifungal drug with anticancer activity, shows potential for oral treatment of skin cancer. There is clinical need for topical ITC for treating low-risk skin carcinogenesis. Our objective was to develop ITC nanoformulations with enhanced anticancer efficacy. Lipid nanocapsules (LNC), either unmodified (ITC/LNC) or modified with the amphiphiles miltefosine (ITC/MF-LNC) or the lipopeptide biosurfactant surfactin (ITC/SF-LNC) as bioactive additives were developed. LNC formulations showed high ITC entrapment efficiency (>98%), small diameter (42–45 nm) and sustained ITC release. Cytotoxicity studies using malignant SCC 9 cells and normal human fibroblasts (NHF) demonstrated significant enhancement of ITC anticancer activity and selectivity for cancer cells by the LNC formulations and a synergistic ITC-amphiphile interaction improving the combination performance. Treatment of intradermal tumor-bearing mice with the ITC nanoformulation gels compared with ITC and 5-FU gels achieved significant tumor growth inhibition that was remarkably enhanced by ITC/MF-LNC and ITC/SF-LNC as well as recovery of skin architecture. Molecularly, tumoral expression of Ki-67 and cytokeratin proliferative proteins was significantly suppressed by LNC formulations, the suppressive effect on cytokeratins was superior to that of 5-FU. These findings provide new evidence for effective topical treatment of low-risk skin carcinogenesis utilizing multiple approaches that involve drug repurposing, nanotechnology, and bioactive amphiphiles as formulation enhancing additives.