Self‐assembled Lipid Nanoparticles for Killing Triple Negative Breast Cancer Cells

Triple negative breast cancers (TNBCs) lacking estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2) on their cell surfaces are highly aggressive, difficult-to-treat and often relapse. Herein, we report on the self-assembled lipid nanoparticles (LNPs) of two new pegylated lipopeptides for killing TNBCs (MDA-MB-231). The pegylated lipopeptides were synthesized by conjugating an n-hexadecyl hydrophobic tail to one end of a (PEG)₂₇ unit the other distal end of which was covalently grafted with two previously reported tumor targeting RGDK- and CGKRK- peptides. The SEM images of the self-assembled LNPs formed upon dissolution of the pegylated lipopeptides in aqueous medium revealed formation of spherical aggregates. The degree of cellular uptake for the self-assembled LNPs formed by the pegylated CGKRK-lipopeptide were found to be significantly higher than that for the self-assembled LNPs formed by the pegylated RGDK-lipopeptide in MCF-7, MDA-MB-231, HEK-293 and HFF cells. Notably, about 60 % TNBCs (MDA-MB-231 cells) were killed upon treatment with commercially available potent JAK2 inhibitor (WP 1066) loaded LNPs of the pegylated RGDK-lipopeptide. Contrastingly, the same treatment killed only about 20 % non-cancerous HEK-293 cells. The self-assembled pegylated LNPs described herein open the door for undertaking preclinical studies in animal models for TNBCs.