Recent advances in nanoparticle systems for improved drug delivery display a great potential for the administration of active molecules. Here, lipid miniemulsions with various internal nanostructures were loaded with the chemotherapeutic agent Paclitaxel. The goal is to assess the impact of internal structures on their efficiency. Previously the structure, the stability and the physico-chemical properties of those carriers were characterized. Modalities of action were addressed by the evaluation of their effects on the tumor cells viability, their cellular uptake by flow cytometry and confocal microscopy detection of fluorescently labeled nanostructured miniemulsions. Nanostructured miniemulsions showed variations in the cell internalization process likely due to differences in the internal structure. All paclitaxel-loaded emulsions were active reservoirs from which Paclitaxel could be released, however bicontinuous cubosomes showed the best efficiency. Considering the fact that these delivery systems can offer a new life to bioactive compounds previously abandoned due to a low aqueous solubility, these data may represent an important step towards the development of new clinical therapeutic strategies against cancers.