Üçlü negatif meme kanseri hücrelerine folik asit polietilenimin polipleksleri ile gen aktarımı

Abstract

Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer and lacks hormonal and growth factor receptors commonly expressed by other types of breast cancer making it difficult to treat by conventional treatments. Although gene therapy might be a therapeutic option, delivery of genes into TNBC cells is still an obstacle. In this study, it was aimed to overcome this obstacle by folic acid (FA) conjugated polyplex formulations to targeting the folate receptor which has been reported to be overexpressed in TNBC cells. Non-covalent complexes of FA and LPEI polyplexes (FA-polyplexes) were prepared at six different ratios. After characterization studies, cytotoxicity and transfection ability were evaluated. Conjugation of FA by increasing amounts of LPEI polyplexes, increased the size from 204.1 to 469.8 nm. Their PDI values were between 0.31-0.51, and zeta potentials were positive. After treatment with polyplex formulations, cell viability was decreased significantly starting from 3:1(w/w) polymer:pDNA ratio and from 3:3:1 (w/w)FA:polyplex ratio. Cell viability decreased below 70% above the 5:1 (w/w) polymer:pDNA ratio. Addition of folic acid to polyplex formulations reversed the cytotoxicity of P3, P4 and P5 formulations. Although LV-RFP pDNA was delivered successfully into 4T1 cells by all formulations, fluorescent microscope images showed that, the optimal formulations were FA-P3 and FA-P4. This gene delivery system, generated by non-covalent conjugation of folic acid to polyplexes, increased the uptake and decreased the cytotoxicity of LPEI polyplexes. Non-covalent complexes of folic acid-LPEI polyplexes represent promising delivery systems in gene therapy, directed against cancer cells expressing folate receptors.