Design and In vitro Validation of Multivalent Dendrimer Methotrexates as a Folate-targeting Anticancer Therapeutic

Abstract

Design of cancer-targeting nanotherapeutics relies on a pair of two functionally orthogonal molecules, one serving as a cancer cell-specific targeting ligand, and the other as a therapeutic cytotoxic agent. The present study investigates the validity of an alternative simplified strategy where a dual-acting molecule which bears both targeting and cytotoxic activity is conjugated to the nanoparticle as cancer-targeting nanotherapeutics. Herein we demonstrate that methotrexate is applicable for this dual-acting strategy due to its reasonable affinity to folic acid receptor (FAR) as a tumor biomarker, and cytotoxic inhibitory activity of cytosolic dihydrofolate reductase. This article describes design of new methotrexate-conjugated poly(amidoamine) (PAMAM) dendrimers, each carrying multiple copies of methotrexate attached through a stable amide linker. We evaluated their dual biological activities by performing surface plasmon resonance spectroscopy, a cell-free enzyme assay and cell-based experiments in FAR-overexpressing cells. This study identifies the combination of an optimal linker framework and multivalency as the two key design elements that contribute to achieving potent dual activity.

The therapeutic effect of methotrexate-conjugated Pluronic-based polymeric micelles on the folate receptor-rich tumors treatment

“…Thus, MTX is unable to cross the cell membrane passively unless being uptaken in an active mechanism which is mediated by cell surface proteins like folate receptor and reduced folate carrier. 21 Thus, MTX may be used as not only an anticancer drug but also a potential targeting ligand. [22][23][24] Therefore, in this manuscript, based on the findings from previous studies, 3,4 we have further elaborated on the mechanism of the affinity between F127/ P105-MTX and folate receptor.…”

“…Based on these results, it was suggested that although MTX has relatively lower affinity to folate receptor compared with FA (K D =~20-100 nM vs 31,32 MTX-conjugated micelles might bind to folate receptor through polyvalent interaction as reported recently. 21,33,34 cellular uptake mechanism of FITclabeled mixed micelles in KBv cells…”

Liposomal formulation of a methotrexate lipophilic prodrug: assessment in tumor cells and mouse T-cell leukemic lymphoma

“…Although FRα-mediated transport of MTX is unlikely to be of clinical importance, 26 it may be involved in the effects produced by MTX nanocarriers. 5 However, neither anti-FRα antibody ( Figure S1B) nor folic acid inhibited L-MTX-DG binding to cells. Notably, the tested carcinoma cells do not belong to lineages highly expressing FR, and an increase in the receptor expression by the privation of vitamin B9 in cultural medium was not endeavored.…”

“…alekseeva et al polyamide dendrimers, 5 polymer nanogels, 6 nanostructured carriers composed of triglycerides and surfactants, 7 quantum dots, 8 polyethylene glycol (PEG)-phospholipid micelles, 9 and liposomes. 10,11 Most of these carriers have insufficient drugloading capacity.…”

Tumor targeting using polyamidoamine dendrimer–cisplatin nanoparticles functionalized with diglycolamic acid and herceptin

“…Additionally, the tumor selectivity of nanoparticles can be fur- 69 ther enhanced in an active manner by employing a targeting moi-70 ety [7]. The surface of nanoparticles can be functionalized with 71 specific ligands that target corresponding cellular receptors over-72 expressed in cancer cells [8]. Among numerous cell surface recep- 73 tors that are present on malignant cells, HER-2 a receptor tyrosine 74 kinase presents itself as an interesting target for achieving tumor 75 specific drug delivery.…”