Chen Jinhao, Ye Mujie, Gu Danyang, Yu Ping, Xu Lin, Xue Bingyang, Yan Lijun, Lu Feiyu, Hu Chunhua, Xu Yanling, Shi Xiaoting, Chen Lingyi, Wang Yan, Bai Jianan, Tian Ye, Tang Qiyun
Department of Geriatric Gastroenterology, Neuroendocrine Tumor Center, Jiangsu Province Hospital, The First Affiliated of Nanjing Medical University, Institute of Neuroendocrine Tumor, Nanjing Medical University, Nanjing, China.
Center for Biomarker Discovery and Validation, National Infrastructures for Translational Medicine (PUMCH), Institute of Clinical Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Science & Peking Union Medical College, Beijing, China.
Int J Biol Sci. 2025 Jan 27;21(4):1478-1496. doi: 10.7150/ijbs.103428. eCollection 2025.
N6-methyladenosine (m6A) is considered the most prevalent RNA epigenetic regulator in cancer. FTO, an m6A demethylase, has been implicated in contributing to the progression of various cancers by up-regulating the expression of multiple oncogenes. However, studies exploring its impact on lipid metabolism in cancer, especially in pNENs, remain scarce. In this study, we demonstrated that FTO was up-regulated in pNENs and played a critical role in tumor growth and lipid metabolism. Mechanistically, we discovered that FTO over-expression increased the expression of APOE in an m6A-IGF2BP2-dependent manner, leading to dysregulation of lipid metabolism. Furthermore, we found APOE could activate the PI3K/AKT/mTOR signaling pathway, thereby enhancing lipid metabolism and proliferative capabilities, by orchestrating the state of FASN ubiquitination. In conclusion, our study reveals the FTO/IGF2BP2/APOE/FASN/mTOR axis as a mechanism underlying aberrant m6A modification in lipid metabolism and provides new insights into the molecular basis for developing therapeutic strategies for pNENs treatment.
N6-甲基腺苷(m6A)被认为是癌症中最普遍的RNA表观遗传调控因子。FTO是一种m6A去甲基化酶,已被证明通过上调多种癌基因的表达促进各种癌症的进展。然而,探索其对癌症脂质代谢影响的研究,尤其是对胰腺神经内分泌肿瘤(pNENs)的研究仍然很少。在本研究中,我们证明FTO在pNENs中上调,并在肿瘤生长和脂质代谢中起关键作用。机制上,我们发现FTO过表达以m6A-IGF2BP2依赖的方式增加载脂蛋白E(APOE)的表达,导致脂质代谢失调。此外,我们发现APOE可以通过协调脂肪酸合酶(FASN)泛素化状态激活PI3K/AKT/mTOR信号通路,从而增强脂质代谢和增殖能力。总之,我们的研究揭示了FTO/IGF2BP2/APOE/FASN/mTOR轴是脂质代谢中异常m6A修饰的潜在机制,并为开发pNENs治疗策略的分子基础提供了新见解。