This study aimed to develop novel temperature-sensitive liposomes loading paclitaxel (PTX-TSL) and evaluate them in vitro to improve the delivery efficiency and targeting of PTX. K237 peptide was conjugated to the terminal NHS of 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[hydroxyl succinimidyl (polyethylene glycol)-(DSPE-PEG-NHS), and K237-modified PTX-TSL (K237-PTX-TSL) was prepared using a film dispersion method. K237-TSL encapsulation with calcein was synthesized and used to determine the cellular uptake of TSL. The morphology of K237-PTX-TSL was observed using a transmission electron microscope. The particle size and potential were measured using a laser particle size analyzer. The phase transition temperature was detected using the differential scanning calorimetry. The Cell Counting Kit-8 assay and flow cytometry were used to evaluate the effects of K237-PTX-TSL on the proliferation and cell cycle of cell lines SKOV-3 and human umbilical vein endothelial cell (HUVEC). The encapsulation efficiency of K237-PTX-TSL was 94.23% ± 0.76%. The particle diameter was 88.3 ± 4.7 nm. K237-PTX-TSL showed a fast release profile at 42 °C, while it was stable at 37 °C. PTX-TSL combined with hyperthermia significantly inhibited the cell proliferation of SKOV-3 cells and HUVECs due to increased cell arrest in the G2/M phase. The half-minimal inhibitory concentration value of K237-PTX-TSL on SKOV-3 cells and HUVECs was 13.61 ± 1.81 and 5.54 ± 0.95 nmol/L, respectively, which were significantly lower than those with PTX-TSL (p < 0.01). K237 modification could increase the targeting efficiency of TSL to cancer cells and vascular endothelial cells, thus resulting in higher cytotoxicities compared with PTX-TSL, which might be a potential formulation for targeting cancer therapy.
Keywords: K237/KDR; nanoliposome; paclitaxel; thermosensitive liposome.