KRAS and lung cancer: For example, Wingless and INT‐1 (WNT) and mitogen‐activated protein kinases (MAPK) signaling pathways and alterations of EGFR, anaplastic lymphoma kinase (ALK), Kirsten rat sarcoma viral oncogene homolog (KRAS), matrix metalloproteinase (MMP), mesenchymal‐epithelial transition (MET) and Live kinase B1 (LKB1) genes have been identified to be involved in brain metastasis9, and WNT, MAPK and NF‐kappaB (NFκB) signaling pathways in bone metastasis and EGFR mutations in lung metastasis of lung cancer.10