RASSF4 and neoplasm: First, for disease types with low RASSF4 expression, including most solid tumors and advanced patients with metabolic diseases, viral vectors such as AAV or lentivirus, or non-viral vectors such as GalNAc-modified lipid nanoparticles, can be used to directly deliver the RASSF4 gene to restore its tumor-suppressing function [118,119].