STK11 and Buschke-Ollendorff syndrome: Our study also demonstrated novel findings indicating that sEV-mediated downregulation of a tumor suppressor gene, LKB1, in primary epithelial cells may also play an important role in chronic rejection after LTx by inducing epithelial-mesenchymal transition by upregulating VIM and α-SMA, leading to the pathogenesis of BOS (146).