PTK2 and cancer: Numerous studies have suggested that CKAP2 promotes tumor cell proliferation, migration, and invasion through the JAK/STAT3 signaling pathway or the FAK-ERK2 pathway, which could contribute to poor disease prognosis (17, 35, 49, 50), as observed in cancers such as gastric adenocarcinoma, hepatocellular carcinoma, cervical carcinoma, and breast carcinoma (20, 22–24).