BACKGROUND: We investigated the impact of SMAD2 linker phosphorylation (pSMAD2L) on overall and disease-free survival, signal transduction, as well as cancer-related processes in non-small cell lung cancer (NSCLC). METHODS: We generated A549 cells constitutively lacking pSMAD2L (A549L(sub)) to gain mechanistic insights and stimulated NSCLC cell lines with inhibitors against cell cycle-associated kinases or TGF