SNAI1 and lung adenocarcinoma: A novel lncRNA ELIT-1, Smad3, and Snail form a positive feedback loop by recruiting Smad3 (Sekelsky mothers against dpp 3) to the promoter of Snail, other TGF-β-target genes, and ELIT-1 itself, enhancing TGF-β/Smad3 signaling and promoting EMT progression in lung adenocarcinoma (LUAD) and GC [44].