The process of NHEJ is completed when the DNA ligase complex ligates the broken ends of the DNA. Ku70-Ku80 are the DNA-dependent protein kinase heterodimeric regulatory factor that forms a link between two broken DNA ends and structurally support, align and protect them from further degradation. W7 inhibitor (W7(N-(6-aminohexyl)-5-chloro1-naphthalenesulfonamide) inhibits the cofactor of inositol hexakisphophate which effects the regulatory factor of Ku heterodimers.