Nanocarriers are heavily researched as drug delivery vehicles capable of sequestering antineoplastic agents and then releasing their contents at the desired location. The feasibility of using such carriers stems from their ability to produce a multimodel delivery system whereby passive, ligand and triggered targeting can be applied in the fight against cancer. Passive targeting capitalizes on the leaky nature of tumor tissue which allows for the extravasation of particles with a size smaller than 0.5 µm into the tumors. Ligand targeting utilizes the concept of receptor-mediated endocytosis and involves the conjugation of ligands onto the surface of nanoparticles, while triggered targeting involves the use of external and internal stimuli to release the carriers contents upon reaching the diseased location. In this review, micelles and liposomes have been considered due to the promising results they have shown in vivo and in vitro and their potential for advancements into clinical trials. Thus, this review focuses on the most recent advancements in the field of micellar and liposomal drug delivery and considers the synergistic effect of passive- and ligand-targeting strategies, and the use of ultrasound in triggering drug release at the tumor site.

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The expansion of human peripheral blood endothelial progenitor cells to obtain therapeutically relevant endothelial colony-forming cells (ECFCs) has been commonly performed on xeno-derived extracellular matrix proteins. For cellular therapy applications, xeno-free culture conditions are desirable to improve product safety and reduce process variability. We have previously described a novel fluorophore-tagged RGD peptide (RGD-TAMRA) that enhanced the adhesion of mature endothelial cells in vitro. To investigate whether this peptide can replace animal-derived extracellular matrix proteins in the isolation and expansion of ECFCs, peripheral blood mononuclear cells from 22 healthy adult donors were seeded on RGD-TAMRA-modified polystyrene culture surfaces.Endothelial colony formation was significantly enhanced on RGD-TAMRA-modified surfaces compared to the unmodified control. No phenotypic differences were detected between ECFCs obtained on RGD-TAMRA compared to ECFCs obtained on rat-tail collagen-coated surfaces. Compared with collagen-coated surfaces and unmodified surfaces, RGD-TAMRA surfaces promoted ECFC adhesion, cell spreading, and clonal expansion. This study presents a platform that allows for a comprehensive in vitro evaluation of peptide-based biofunctionalization as a promising avenue for ex vivo ECFC expansion. K E Y W O R D Sendothelial progenitor cells, ex vivo expansion, extracellular matrix-derived peptides, surface modification, vascular regeneration, xeno-free

In this paper, we report on a potential cancer drug delivery system that utilizes the ligand targeting of the folate receptor. Our drug delivery system consists of Pluronic-P105 micelles, targeted with folic acid moieties. A melanoma folate positive (FR+) (B16-F10), and a fibroblast folate negative (FR-) (NIH-3T3) cell lines are used to compare the cellular accumulation of a chemotherapeutic drug (Doxorubicin) when the delivery is mediated by folated Pluronic P105 micelles. In order to obtain a proper comparison, we corrected for the quenching of Doxorubicin by folic acid molecules and illustrated the significant effect of quenching on the analysis of similar systems. Results show an 80% increase in the accumulation of the antineoplastic agent in the FR+ cell line, when compared to the FR- cell line, thus providing evidence that the efficacy of Pluronic micelles, as drug delivery vehicles, can be enhanced via folic acid targeting.