Uterine fibroids (UF) occupies the 2nd place in the structure of gynecological pathology and is often the cause of infertility. Precise ultrasound localization makes the disease a perfect target for suicidal gene therapy in situ. However, excessive extracellular matrix (ECM) of UF represents a formidable barrier for gene delivery by means of nanoparticles. Coating with polyanions can provide colloidal stability of the polyplexes and resistance to ECM. We developed αvβ3-integrin-targeted peptide-based carrier and anionic peptide coating for DNA delivery into αvβ3-expressing cells, including primary leiomyoma cells (PLC).

Arginine-histidine-rich peptide carriers conjugated with cycloRGD ligand were synthesized. The physicochemical properties of DNA-polyplexes with anionic coating were tested. The specificity of the DNA delivery was demonstrated in competitive uptake and transfection experiments in pancreatic carcinoma cells (PANC-1). Suicidal gene therapy with HSV1-TK gene with subsequent ganciclovir treatment was held for PLC obtained after myomectomy.

DNA condensation analysis shows that the addition of anionic peptides does not lead to the destruction of the nucleopeptide complexes. Moreover, negatively charged coating allowed successful transfection in the presence of serum. AlamarBlue and TrypanBlue exclusion assays of PLC showed a decline of proliferative activity among cells transfected with HSV1-TK gene carrying complexes in comparison with the control LacZ gene transfected cells.

The study shows that the utilization of peptide carriers modified with RGD-ligand and negatively charged peptides is a promising approach for the development of targeted DNA delivery systems. Developed carriers demonstrated high specificity and transfection efficacy of leiomyoma cells with subsequent successful suicidal gene therapy.