Silencing of HMGA2 by siRNA Loaded Methotrexate Functionalized Polyamidoamine Dendrimer for Human Breast Cancer Cell Therapy

Abstract

The transcription factor high mobility group protein A2 (HMGA2) plays an important role in the pathogenesis of some cancers including breast cancer. Polyamidoamine dendrimer generation 4 is a kind of highly branched polymeric nanoparticle with surface charge and highest density peripheral groups that allow ligands or therapeutic agents to attach it, thereby facilitating target delivery. Here, methotrexate (MTX)- modified polyamidoamine dendrimer generation 4 (G4) (G4/MTX) was generated to deliver specific small interface RNA (siRNA) for suppressing HMGA2 expression and the consequent effects on folate receptor (FR) expressing human breast cancer cell lines (MCF-7, MDA-MB-231). We observed that HMGA2 siRNA was electrostatically adsorbed on the surface of the G4/MTX nanocarrier for constructing a G4/MTX-siRNA nano-complex which was verified by changing the final particle size and zeta potential. The release of MTX and siRNA from synthesized nanocomplexes was found in a time- and pH-dependent manner. We know that MTX targets FR. Interestingly, G4/MTX-siRNA demonstrates significant cellular internalization and gene silencing efficacy when compared to the control. Besides, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay demonstrated selective cell cytotoxicity depending on the folate receptor expressing in a dose-dependent manner. The gene silencing and protein downregulation of HMGA2 by G4/MTX-siRNA was observed and could significantly induce cell apoptosis in MCF-7 and MDA-MB-231 cancer cells compared to the control group. Based on the findings, we suggest that the newly developed G4/MTX-siRNA nano-complex may be a promising strategy to increase apoptosis induction through HMGA2 suppression as a therapeutic target in human breast cancer.

Significance of High-Mobility Group A Protein 2 Expression in Pancreatic Ductal Adenocarcinoma and Ampullary Adenocarcinoma

“… 12 Both HMGA1 and HMGA2 are suppressed or absent in most adult differentiated tissues, 13 , 14 although their expression is observed in embryonic tissues. 15 , 16 There are studies evaluating HMGA2 protein expression in malignant epithelial tumors such as stomach, 17 colon, 18 breast, 19 lung, 20 bladder, 21 skin, 22 and kidney 23 carcinomas. These studies report that HMGA2 protein plays a role in tumor development and is not expressed in the normal epithelial tissue.…”

Oral delivery of RNAi for cancer therapy

“…HMGA2 siRNA was electrostatically adsorbed on the dendrimers and effectiveness on folate receptor-expressed breast cancer cell lines such as MCF-7, and MDA-MB-231 was assessed. The delivery of siRNA and MTX from the dendrimers by smart release (pH and time-dependent manner) demonstrated cell internalization and gene silencing effects [ 115 ]. Dendrimers have been extensively researched for successful gene delivery however oral gene delivery with dendrimers is yet to be explored.…”

Remodeling the tumor immune microenvironment via siRNA therapy for precision cancer treatment

“…Similarly, Gaballu et al. [115] fabricated methotrexate (MTX)-modified polyamidoamine dendritic molecule 4 (G4) (G4/MTX) to deliver siRNA- HMGA2 . MTX endowed the nanocapsules to target human breast cancer cell lines (MCF-7, MDA-MB-231) expressing folate receptor (FR).…”