转移癌细胞在整个转移级联过程中遇到多种应激。已知氧化应激是转移定植的主要障碍，因此转移癌细胞必须重新连接其代谢途径以提高其抗氧化能力。 NADPH 对于细胞抗氧化剂的再生至关重要，并且多种 NADPH 再生途径已被证明在转移中发挥作用。我们发现转移性黑色素瘤细胞的 NADPH 和 NADP 水平均增加，表明 NADP 的从头生物合成增加。 NADP 的从头生物合成是通过 NAD 激酶 (NADK) 催化的单一酶促反应发生的。在这里，我们发现不同的 NADK 异构体在转移性黑色素瘤细胞中差异表达，其中异构体 3 在转移中特异性上调。我们发现，与异构体 1 相比，异构体 3 在扩大 NADP(H) 池、增强氧化应激抵抗力和促进转移定植方面更有效。我们发现，氧化应激通过 NRF2 的作用，转录上调异构体 3。总之，我们的工作展示了 NADK 同工型在氧化应激抵抗和转移中的先前未表征的作用，并表明 NADK 同工型 3 是转移性疾病的潜在治疗靶点。版权所有 © 2024 作者。由 Elsevier B.V. 出版。保留所有权利。

Metastasizing cancer cells encounter a multitude of stresses throughout the metastatic cascade. Oxidative stress is known to be a major barrier for metastatic colonization, such that metastasizing cancer cells must rewire their metabolic pathways to increase their antioxidant capacity. NADPH is essential for regeneration of cellular antioxidants and several NADPH-regenerating pathways have been shown to play a role in metastasis. We have found that metastatic melanoma cells have increased levels of both NADPH and NADP+ suggesting increased de novo biosynthesis of NADP+. De novo biosynthesis of NADP+ occurs through a single enzymatic reaction catalyzed by NAD+ kinase (NADK). Here we show that different NADK isoforms are differentially expressed in metastatic melanoma cells, with Isoform 3 being specifically upregulated in metastasis. We find that Isoform 3 is more potent in expanding the NADP(H) pools, increasing oxidative stress resistance and promoting metastatic colonization compared to Isoform 1. We have found that Isoform 3 is transcriptionally upregulated by oxidative stress through the action of NRF2. Together, our work presents a previously uncharacterized role of NADK isoforms in oxidative stress resistance and metastasis and suggests that NADK Isoform 3 is a potential therapeutic target in metastatic disease.Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.