In a more recent study, multiplex immunofluorescence staining in 105 SCLC and 95 non-NSCLC patients, as well as 37 healthy donors, revealed that FAK and phospho-FAK (Y397) expression was significantly higher in lung cancer than in normal lung, and significantly higher in SCLC when compared to NSCLC tissues (p < 0.01). This evidence concerns the gene PTK2 and lung cancer.