Vaginal formulation development: A strategy based on aptamer-guided liposome for human papillomavirus-induced lesions

Human Papillomavirus (HPV) is the main cause of cervical cancer, and formulations have been widely used to treat vaginal lesions caused by HPV. Herein, liposomes with acridine orange derivative C₈ were produced and functionalized with AT11 aptamer. Subsequently, they were incorporated into a formulation, prepared based on the universal placebo formulation, which included Thymus vulgaris (TEO) or Origanum vulgare (OEO) essential oils. The formulation was technologically characterized and permeation of C₈ into vaginal tissue was determined. To assess its biological effect, cell viability and internalization tests were carried out using the MTT assay and confocal microscopy, respectively, and antimicrobial susceptibility was also assessed. The prepared formulations were able to internalize cells and reduce cell viability, especially in cancer cell lines. Additionally, formulations showed promising antibacterial and antifungal effects. The effect of the formulation containing TEO and the C₈ AT11 liposomes was also tested in vivo in HPV16 transgenic and wild type mice. Briefly, the formulation proved to be safe for animals and presented some therapeutic potential, namely through the reduction of ear epithelial cells' proliferation. Overall, results suggest that essential oils can increase the anticancer potential of liposomes with associated C₈ and AT11 promotes their selectivity towards cancer cells.