AHCYL1 plays a dual role in tumors; it acts as a tumor suppressor in gastric, ovarian, and breast cancers while promoting chemotherapy resistance in malignant melanoma (Nakazawa et al., 2019; Jeong et al., 2012; Chen et al., 2024; Wittig et al., 2002). The gene discussed is AHCYL1; the disease is breast carcinoma.