Targeted nanoformulation of C1 inhibits the growth of KB spheroids and cancer stem cell-enriched MCF-7 mammospheres

C1, a synthetic analog of curcumin, has been reported to show potent antiproliferative effects against a variety of cancer cells. Here, we report a strong anticancer activity of the folate receptor-targeted lipid nanoparticle formulation of C1 against cancer cells and cancer stem cells both in 2D culture and 3D spheroids. The size of the C1 encapsulated folic acid functionalized nanoliposomes (Lipos-C1) was determined to be 83 ± 17 nm. Lipos-C1 nanoparticles displayed sustained C1 release kinetics at both pH 7.4 and 5.5. The folate receptor (FR) targeted nanoliposomes were internalized into FR-positive KB cells via the folate receptor-mediated endocytosis process. Lipos-C1 killed KB cells much more efficiently than C1. Lipos-C1 depolymerized microtubules, generated ROS, caused DNA damage, and induced apoptosis in KB cells. Importantly, Lipos-C1 strongly inhibited the growth of the 3D KB spheroids than C1. Interestingly, Lipos-C1 also suppressed cancer stem cells (CSCs) enriched MCF-7 mammosphere growth by impeding breast cancer stem cells (BCSCs) enrichment, growth, and proliferation. The results suggested that Lipos-C1 could be a promising nanoformulation for cancer chemotherapy.