ABSTRACT
To target neovasculature and tumor cells, a novel cationic liposome with verteporfin (BPD) active-loaded in lumen (CLL) was designed and its basic in vitro and in vivo behaviors were evaluated in this study. Calcium acetate gradient loading method was applied to encapsulate BPD actively and cationic lipid (2,3-dioleoy-loxy-propyl)-trimethylammonium (DOTAP) was added by post-insertion for the positive charge of CLL. Results of characterization showed that the diameter and zeta-potential of CLL were around 100 nm and 28 mV, respectively. Compared with passive loading liposomes, CLL significantly enhanced the stability of BPD loading. What's more, the loaded BPD in lumen could switch off the fluorescence and photosensitization during blood circulation by homo-fluorescence resonance energy transfer (homo-FRET) effect, leading to the diminished phototoxicity to normal tissues. In vitro cellular uptake and cytotoxicity assay exhibited that positive charge dramatically enhanced the uptake of CLL both in vascular endothelial cells and tumor cells leading to superior therapeutic efficacy. In vivo study further showed that CLL reduced the clearance rate and increased tumor accumulation compared with passive loading group. Quantitative results of exvivo organ indicated that negligible CLL distributed in normal organs contributing to low phototoxicity. Animal experiments were conducted according to the Guidelines of the Experimental Animal Ethics Committee of Peking University Health Science Center and International Animal Experiments. In conclusion, we successfully designed a novel cationic targeting liposome that overcame the limitations of passive loading and significantly enhanced the efficacy of photodynamic therapy.
ABSTRACT
The autonomic nervous system contributes to prostate cancer proliferation and metastasis. However, the exact molecular mechanism remains unclear. In this study, muscarinic acetylcholine receptor M1 (CHRM1) expression was measured via immunohistochemical analysis in human prostate cancer tissue array slides. PC-3, LNCaP, and A549 cells were treated with pirenzepine or carbachol, and the cell migration and invasion abilities were evaluated. Western blotting and quantitative real-time PCR were performed to measure GLI family zinc finger 1 (GLI1), patched 1 (PTCH1), and sonic hedgehog (SHH) expression levels. High expression of CHRM1 was found in early-stage human prostate cancer tissues. In addition, the selective CHRM1 antagonist pirenzepine inhibited PC-3, LNCaP, and A549 cell migration and invasion, but the agonist carbachol promoted the migration and invasion of these three cell lines. Muscarinic signaling can be relayed by hedgehog signaling. These data show that CHRM1 is involved in the regulation of prostate cancer migration and invasion through the hedgehog signaling pathway.
ABSTRACT
This study was designed to investigate the impacts of particle shape of micelles on cell uptake and tumor imaging applications. We designed and synthesized an ultra-pH sensitive PEG-iPDPA diblock polymer, and prepared it into wormlike micelles and spherical micelles by thin-film dispersion method and modified solvent evaporation method, respectively. Firstly, the pH responsiveness of two kinds of micelles was investigated in vitro. Both forms of micelles responded to pH sensitively, and each of them could reach 100 times of ON/OFF fold after conjugated with BDP fluorescent probe. Moreover, the cellular uptake of two forms of micelles depended on the concentration and incubation time. However, the amount of cellular uptake of spherical micelles was much higher than that of the wormlike micelles, which proved that the shape of nanoparticles had a great influence on the cellular uptake. The results of in vivo imaging revealed that the spherical micelles had a better tumor accumulation as well as tumor imaging outcomes. Finally, the biosafety of micelles was tested by MTT assay and H&E staining, which indicated that none of the two kinds of micelles had obvious toxicity. Collectively, these results suggest that the spherical micelles could be a better carrier compared with wormlike micelles in terms of cellular uptake, tumor accumulation and tumor detection.