Although CISD1 has been identified as a prognostic biomarker in several cancers, such as breast cancer,17,18 hepatocellular carcinoma,19 gastric cancer,20 and bladder cancer,21 there is still a lack of systematic pan-cancer analysis of CISD1, which is vital to the understanding of its broad implications in cancer biology and clinical oncology. Here, CISD1 is linked to breast cancer.