MET and lung cancer: The non-selective tyrosine kinase inhibitor (TKI) for MET crizotinib has been widely used in the clinical treatment of lung cancer patients including those with BM [38], and the selevtive MET-TKI capmatinib, which also inhibits the phosphorylation of MET in PC9-BrM cells (Fig. S6), has been recently approved and applied for NSCLC treatment [39].