Anti-PD-1 and PD-L1 therapies may prove effective against LKB1 mutant squamous lung tumours as a recent study describing an Lkb1/Pten-deficient GEMM of squamous cell lung cancer found that tumours expressed high PD-L1 levels (Xu et al, 2014). This evidence concerns the gene STK11 and squamous cell lung carcinoma.