After systemic administration, poly-siRNA (RFP or VEGF)-tGC nanoparticles showed effective RFP gene silencing or significant inhibition of neovascularization in vivo, leading to effective tumor suppression of RFP-SCC7 tumors compared to poly-siRNA (RFP or VEGF) and poly-siRNA (RFP or VEGF/PEI polyplexes). Here, VEGFA is linked to neoplasm.