PTK2 and cancer: Currently, several FAK inhibitors, such as 2,4-diaminopyridine derivative GSK2256098 and 2,4-diaminopyrimidine derivative Defactinib (Figure 1), are currently being evaluated in clinical trials for cancer treatment, in addition to the 2,4-diaminopyrimidine derivative TAE-226 (Figure 1) which displayed potent antitumor impact in different cancer types in vivo and in vitro and usually used as a reference drug7,15,.16