PTK2 and hepatocellular carcinoma: Based on the TCGA database [110], the FAK copy number gain is found in 26% of ovarian epithelial tumors, 11.5% of oesophageal squamous cell, 10.4% of invasive breast, 9.7% of hepatocellular carcinoma, and less frequently in other tumors, such as 4.8% of NSCLC (Figure 3B), while there are no data related to SCLC.