Alginate-Chitosan Hydrogels Containing shRNA Plasmid for Inhibition of CTNNB1 Expression in Breast Cancer Cells.

The hydrogels prepared with alginate and chitosan polymers were prepared to deliver the shRNA-encoding plasmid (pshRNA) to MDA-MB-231 cells for the inhibition of ß-catenin (CTNNB1), which was reported to be overexpressed in breast cancer. Polyion complex hydrogels prepared using sodium alginate and chitosan were characterized by Fourier transform infrared spectrometry (FTIR) analysis, scanning electron microscope (SEM) analysis, swelling, and degradation properties. After the release properties and serum stability of pshRNA-loaded hydrogels were determined, their cytotoxicity, transfection efficacy, and effects on CTNNB1 expression were investigated in MDA-MB-231 cells. All hydrogels were shown to protect pshRNA from the enzymatic activity of serum and to deliver pshRNA to cells efficiently. As a result of transfection studies, pshRNA-loaded hydrogels reduced CTNNB1 expression by up to 30.25%. Cell viability also decreased by 38% in cells treated with 2.5% (w/v) alginate-chitosan hydrogel containing pshRNA targeting CTNNB1. Alginate-chitosan hydrogels were shown to be a suitable matrix system for local gene delivery.

Combination therapy with chitosan/siRNA nanoplexes targeting PDGF-D and PDGFR-ß reveals anticancer effect in breast cancer.

BACKGROUND: Platelet derived growth factors (PDGF)-D and the expression of its receptor increase in neoplastic progression of cancer. Co-silencing of growth factor and receptor can be suggested as an important strategy for effective cancer therapy. In the present study, we hypothesized that suppression of PDGF-D signaling pathway with small interfering RNAs (siRNAs) targeting both PDGF-D and PDGF receptor (PDGFR)-ß is a promising strategy for anticancer therapy. METHODS: Chitosan nanoplexes containing dual and single siRNA were prepared at different weight ratios and controlled by gel retardation assay. Characterization, cellular uptake, gene silencing and invasion studies were performed. The effect of nanoplexes on breast tumor growth, PDGF expression and apoptosis was investigated. RESULTS: We have shown that downregulation of PDGF-D and PDGFR-ß with chitosan/siRNA nanoplex formulations reduced proliferation and invasion in breast cancer cells. In the in vivo breast tumor model, it was determined that the intratumoral administration of chitosan/siPDGF-D/siPDGFR-ß nanoplexes markedly decreased the tumor volume and PDGF-D and PDGFR-ß mRNA and protein expression levels and increased apoptosis. CONCLUSIONS: According to the results obtained, we evaluated the effect of PDGF-D and PDGFR-ß on breast tumor development and showed that RNAi-mediated inhibition of this pathway formulated with chitosan nanoplexes can be considered as a new breast cancer therapy strategy.

Investigation of therapeutic effects in the wound healing of chitosan/pGM-CSF complexes

Abstract Granulocyte macrophage colony-stimulating factor (GM-CSF) has been shown to promote the growth, proliferation, and migration of endothelial and keratinocyte cells. Chitosan has been widely used as a biopolymer in wound-healing studies. The aim of this study was to investigate the in vitro proliferative effects of chitosan/pGM-CSF complexes as well as the therapeutic role of the complexes in an in vivo rat wound model. The effect of complexes on cell proliferation and migration was examined. Wounds were made in Wistar-albino rats, and examined histopathologically. The cell proliferation and migration were increased weight ratio- and time-dependently in HaCaT and NIH-3T3 cell lines. Wound healing was significantly accelerated in rats treated with the complexes. These results showed that the delivery of pGM-CSF using chitosan complexes could play an accelerating role in the cell proliferation, migration, and wound-healing process.