ABSTRACT

Breast cancer is the most common cancer type among women and is the second most common cause of death after lung cancer. INhibitor of Growth (ING) transcript levels is often suppressed in cancer cells, which makes it a promising candidate for cancer therapy. In this study, it was aimed to formulate a polyplex that effectively carry and deliver pING4 to breast cancer cells.

PEI (Polyethyleneimine)-based non-viral vectors were synthesized and characterized for plasmid DNA delivery. Complexation was carried out by electrostatic interactions between the synthesized polymeric vector and plasmid DNAs. Characterization studies were carried out by testing SDS-induced decomplexation, DNase I protection and serum stability of polyplexes. Subsequently, polyplexes tested on MCF-7 cells for anticancer activity with XTT cell viability assay. Finally, western blot analysis performed against ING4 protein.

Polyplexes that carried ING4 gene showed significantly lower cell viability than the control polyplexes. During the 5-day viability assay, lowest cell viability observed in day 4. Approximately 69% cell viability observed with ING4 treatment while control group showing UNCORRECTED PROOF 2 no cell death at day 4. Which means prepared delivery systems didn’t show a toxic effect on MCF-7 cells when treated alone. Moreover, MCF10A normal mammary cell line used as a positive control. For the confirmation of overexpressed ING4 protein in treatment groups, western blot assay conducted. Unlike the control groups, the overexpression of ING4 protein was clear in wells with treatment group.

With aforementioned results, our work suggests that ING4 gene delivery with prepared PEI-based non-viral delivery systems is a promising approach for breast cancer treatments.