XRCC6 and cancer: The extra amounts of this complex were detected in different cancer cells like HepG2 cells, in which acetylation of Ku70 and break‐up of c‐FLIP/Ku70 complex facilitated ubiquitination of c‐FLIP and resulted in more vulnerability of the cancerous cells to apoptosis through increasing TNF‐related apoptosis‐inducing ligand (TRAIL) as crucial apoptosis primarily factor.44