SOD2 and neoplasm: MnSOD initially appears to acts as a tumor suppressor by inhibiting the ROS and preventing cellular damage; however, once the transformation to malignant cells has taken place, the results of several studies infer that the MnSOD acts to protect the malignant cell both from chemotherapy [28,30] and from radiation therapy [31,32] to allow for its progression, replication, and metastasis.