Development of Liposome Formulations of Tamoxifen and Assessment of Caco-2 Cell Transportation Properties

Breast cancer is the most common type of cancer and known to be the second cause of death among the women worldwide. Nanosized drug delivery systems such as liposomes and nanoparticles have been widely used to enhance permeability and bioavailability of the cancer agents with low solubility. In addition, these systems provide enhanced efficacy and/or reduced toxicity and less side effects. Tamoxifen is the first representive of the SERM (Selective Estrogen Receptor Modulators) group drugs, which is approved by FDA for the treatment of estrogen positive breast tumors and the most common hormonal treatment for all stages of breast cancer. In this study, new oral liposome formulations of tamoxifen were developed using dimethyl-β-cyclodextrin (DM-β-CD) and sodium taurocholate (NaTC) as absorption enhancers. Caco-2 (Human colorectal carcinoma cell line) model was used to investigate oral absorption properties of developed liposome formulations. The liposome formulations’ cytotoxic properties, Caco-2 transportation properties were investigated comparatively with solutions, transepithelial electrical resistance (TEER) values were measured and apparent permeability coefficients (Papp) were calculated. According to the results, DM-β-CD successfully enhanced tamoxifen transportation. While the initial TEER value of Caco-2 cell monolayer was 285 Ω, 226 Ω was measured for tamoxifen+DM-β-CD liposomes at the end of 24 hours. This result indicated that DM-β-CD in liposome formulation, increased tamoxifen transport by opening tight junctions. Liposome formulation is a promising approach for oral tamoxifen treatment.