KRAS and neoplasm: For example, activating mutations in KRAS frequently occur with loss-of-function mutations in the gene STK11, which encodes the tumor suppressor liver kinase B1 (LKB1), resulting in decreased patient survival, de novo resistance to targeted treatments and immunotherapies, and increased likelihood of tumor recurrence (Cancer Genome Atlas Research Network 2014, Skoulidis et al. 2018, Caiola et al. 2018).