In addition, a low level of GPx3 is an independent predictive marker of the local recurrence of early-stage invasive breast cancer in patients undergoing breast-conserving surgery and radiotherapy, regardless of the patient’s clinicopathological parameters [104]; this observation suggests that inactivation of the GPx3 gene by hypermethylation of the promoter may contribute to breast cancer progression. The gene discussed is GPX3; the disease is breast cancer.