Amd1, also known as S-adenosylmethionine decarboxylase proenzyme, is a key enzyme involved in the synthesis of spermine (SPM) and spermidine (SPD) [1-5, 9]. Polyamines like SPM and SPD are associated with multiple cellular processes. Amd1 is also involved in pathways such as the mTORC1-dependent regulation of polyamine metabolism [3]. It has been found to be an important gene in maintaining normal cellular functions and its dysregulation is related to various diseases.

In cancer research, gene knockout (KO) and conditional knockout (CKO) mouse models have been used to study Amd1. In hepatocellular carcinoma (HCC), Amd1 knockdown in mouse models showed that it could affect the proliferation, metastasis, and stemness of HCC cells. High Amd1 levels promoted the expression of certain stem-related factors through FTO-mediated mRNA demethylation [1]. In breast cancer, overexpression of Amd1 enhanced tumor cell proliferation and growth, and in chronic myeloid leukemia, depletion of Amd1 in vivo led to severe impairment of leukemia progression and differentiation of leukemic stem cells [2,4]. In prostate cancer, mTORC1-dependent regulation of Amd1 was validated in mouse models, and in gastric cancer, knockdown of Amd1 in a tumor xenograft model suppressed tumor growth [3,5].

In conclusion, Amd1 is crucial for maintaining normal cellular functions related to polyamine synthesis. Through model-based research, especially KO/CKO mouse models, its role in promoting tumorigenesis and disease progression in various cancers such as HCC, breast cancer, chronic myeloid leukemia, prostate cancer, and gastric cancer has been revealed. Understanding Amd1's functions provides potential targets for cancer therapy.