CLDN1 and cancer: To further validate the molecular effects of STAMBPL1 on EMT, we used CRISPR/Cas9 genome editing approach to generate a STAMBPL1 gene knockout (KO) in NCI-H838 cancer cells (Supplementary Fig. S2a), in which we assessed both the mRNA and protein level of EMT markers, including N-cadherin (CDH2), Claudin-1 (CLDN1), ZO-1 (TJP1), β-catenin (CTNNB1) beyond E-cadherin (CDH1) and vimentin (VIM) (Fig. 2e, f).