The efficiency of membrane transport of vitamin B6 coupled to poly(ester amine) gene transporter and transfection in cancer cells

Vitamin B₆ (VB₆) plays an essential role as a coenzyme in various cellular metabolic functions, including DNA biosynthesis for cellular growth and proliferation. VB₆ is taken up by cells through facilitated diffusion via VB₆ transporting membrane carrier (VTC). In this study, we demonstrated that the VB6-coupled poly(ester amine) (VBPEA) gene transporter utilizes this uptake mechanism, leading to enhanced vector transport inside the rapidly proliferating cancer cells with relatively high affinity. Physicochemical characterization, cell viability assays, and transfection studies showed VBPEA to meet the standards of a good transfection agent. Competitive inhibition of VBPEA uptake by its structural analog 4'-deoxypyridoxine hydrochloride revealed the involvement of VB₆ specific transporting membrane carrier in VBPEA internalization in tumor cells. VBPEA elicit higher transfection levels in lung cancer cells than in normal lung cells, indicating that cancer cells which have a high demand for VB₆, have a higher affinity for VB₆-coupled vector. VB₆ coupling to the gene transporter is important to enforce a high level of VTC-mediated endocytosis compared to VB₆ alone. This system illustrated how understanding of the VB₆ membrane transporter specificity allowed for the design of a VB₆-coupled gene transporter with accelerated transfection activity in cancer cells owing to an advanced mode of internalization.