Currently, SPN has been described as a tumor suppressor gene in the context of different human tumors, such as renal carcinomas, lung adenocarcinomas, ovarian carcinoma, chronic myeloid leukemia, gastric and colorectal cancer, head and neck carcinoma, hepatocellular carcinoma, and breast cancer [90,93,94,95,116,117]. Here, SPN is linked to breast cancer.