Thus, the acquired radioresistant phenotype is long-lasting and possibly irreversible as a result of the constitutive activation of AKT/GSK3β/cyclin D1/Cdk4 pathway, which is induced by a positive feedback loop mediated through the cyclin D1 overexpression, which triggers the development of radioresistance in tumor cells (58). This evidence concerns the gene GSK3B and neoplasm.