The Fate of Sialic Acid and PEG Modified Epirubicin Liposomes in Aged versus Young Cells and Tumor Mice Models

Abstract

In preclinical studies of young mice, nanoparticles showed excellent anti-tumor therapeutic effects by harnessing Peripheral Blood Monocytes (PBMs) and evading the immune system. However, the changes of age will inevitably affect PBMs and the immune system, and there is a serious lack of relevant research. Sialic acid (SA)-octadecylamine (ODA) was synthesized, and SA- or polyethylene glycol (PEG)-modified epirubicin (EPI) liposomes (EPI-SL and EPI-PL, respectively) were prepared to explore differences in antitumor treatment using 8-month-old and 8-week-old Kunming mice. Based on presented data, 8-month-old mice had more PBMs in peripheral blood than 8-week-old mice, and age differences resulted in different anti-tumor treatment effects following EPI-SL and EPI-PL treatment. Following EPI-PL administration, the tumor volume was significantly smaller in 8-week-old mice than in 8-month-old mice (* p < 0.05). Eight-month-old mice treated with EPI-SL (8M-SL) presented no damage to healthy tissue, with a 100% survival rate, and 50% mice in 8M-SL showed ‘shedding’ of tumor tissues from the growth site. Accordingly, 8-month-old mice treated with EPI-SL achieved the best therapeutic effect at different ages and with different liposomes. EPI-SL could improve the antitumor effect of 8-week-old and 8-month-old mice.

Sialic acid-decorated liposomes enhance the anti-cancer efficacy of docetaxel in tumor-associated macrophages

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A potential platform of combining sialic acid derivative-modified paclitaxel cationic liposomes with antibody–drug conjugates inspires robust tumor-specific immunological memory in solid tumors

“…The phenomenon of tumor shedding has also been reported in the previous studies. 19,[57][58][59] We attempt to explain the mechanism by which the tumors were shed with a hypothesis focusing on the microtubulin. To begin with, the first step in co-administration is the intravenous administration of PTX cationic liposomes.…”

Cleavable-Branched Polymer-Modified Liposomes Reduce Accelerated Blood Clearance and Enhance Photothermal Therapy

“…A modified ethanol injection method was used to prepare liposomes. 42 The DSPE-mPEG 1,2K , CH, DOTAP, and PC-98T (6:1:3:15, m/m/m/m) were dissolved using absolute ethyl alcohol, and ICG was dissolved in water (ICG/DOTAP ). After a 4 h incubation, the medium containing PEGylated cationic liposomes was added.…”

“…A modified ethanol injection method was used to prepare liposomes. 42 The DSPE-mPEG 1,2K , CH, DOTAP, and PC-98T (6:1:3:15, m/m/m/m) were dissolved using absolute ethyl alcohol, and ICG was dissolved in water (ICG/DOTAP = 2:3, m/m). After the ethanol was dried at 50 °C, the ICG solution was added to the phospholipid material and stirred for 20 min to produce the prime liposomes.…”