STK11 and neoplasm: To study the biological contributions of LKB1 mutant isoforms to tumor cells, we initially infected A549 cells, which lack the expression of LKB1, with an inducible lentiviral vector containing the different LKB1 isoforms allowing the expression of physiological amounts of LKB1 (Fig. 2b, c and Supplementary Fig. 1b, c).