Poly(amido amine) is an ideal carrier of miR-7 for enhancing gene silencing effects on the EGFR pathway in U251 glioma cells.

microRNAs are regarded as promising drugs for glioma gene therapy. However, conventional administration routes, such as oral administration and intravenous infusion, present low efficiency due to the blood-brain barrier and intercellular retention, thereby limiting their application. Recent studies showed poly(amido amine) (PAMAM) was a candidate carrier due to its high solubilization, delayed release and low toxicity. In the present study, U251 human brain glioma cells were transfected with the miR-7 gene using PAMAM as the vector to determine the transfection efficiency and therapeutic effects in vivo and in vitro. We found that PAMAM exhibited higher transfection efficiency and longer duration of action compared with liposome delivery, and miR-7 efficiently silenced some genes involved in the epidermal growth factor receptor (EGFR) pathway and achieved favorable effects in treating glioma in vivo and in vitro. These investigations provide a basis for developing high-efficiency micromolecular drug delivery.