Un-methylation of NUDT21 represses docosahexaenoic acid biosynthesis contributing to enzalutamide resistance in prostate cancer

NUDT21 lactylation reprograms alternative polyadenylation to promote cuproptosis resistance

Alternative polyadenylation (APA) is critical for shaping transcriptome diversity and modulating cancer therapeutic resistance. While lactate is a well-established metabolic signal in cancer progression, its role in APA regulation remains unclear. Here, we demonstrate that L-lactate-induced lactylation of NUDT21 drives transcriptomic reprogramming through APA modulation. NUDT21 lactylation enhances its interaction with CPSF6, facilitating CFIm complex formation and inducing 3' untranslated region (UTR) lengthening of FDX1. Extension of the FDX1 3' UTR attenuates its protein output, thereby conferring resistance to cuproptosis in esophageal squamous cell carcinoma (ESCC). Furthermore, we identify AARS1 as the lactylation "writer" catalyzing NUDT21 K23 lactylation, and HDAC2 as its enzymatic "eraser". Clinically, elevated levels of both LDHA and NUDT21, as well as increased K23-lactylated NUDT21, are associated with reduced FDX1 expression and worse prognosis in ESCC patients. Notably, combined targeting of the lactate-NUDT21-FDX1-cuproptosis axis with the clinical LDHA inhibitor stiripentol and the copper ionophore elesclomol synergistically suppressed tumor growth. Collectively, our work identifies lactylated NUDT21 as a critical factor linking cellular metabolism to APA and proposes a promising therapeutic strategy for ESCC treatment.

Cuproptosis-related genes and agents: implications in tumor drug resistance and future perspectives

In the field of tumor treatment, drug resistance remains a significant challenge requiring urgent intervention. Recent developments in cell death research have highlighted cuproptosis, a mechanism of cell death induced by copper, as a promising avenue for understanding tumor biology and addressing drug resistance. Cuproptosis is initiated by the dysregulation of copper homeostasis, which in turn triggers mitochondrial metabolic disruptions and induces proteotoxic stress. This process specifically entails the accumulation of lipoylated proteins and the depletion of iron-sulfur cluster proteins within the context of the tricarboxylic acid cycle. Simultaneously, it is accompanied by the activation of distinct signaling pathways that collectively lead to cell death. Emerging evidence highlights the critical role of cuproptosis in addressing tumor drug resistance. However, the core molecular mechanisms of cuproptosis, regulation of the tumor microenvironment, and clinical translation pathways still require further exploration. This review examines the intersection of cuproptosis and tumor drug resistance, detailing the essential roles of cuproptosis-related genes and exploring the therapeutic potential of copper ionophores, chelators, and nanodelivery systems. These mechanisms offer promise for overcoming resistance and advancing tumor precision medicine. By elucidating the molecular mechanisms underlying cuproptosis, this study aims to identify novel therapeutic strategies and targets, thereby paving the way for the development of innovative anti-cancer drugs.

IGF2BP3 recruits NUDT21 to regulate SPTBN1 alternative polyadenylation and drive ovarian cancer progression

Ovarian cancer (OC) is one of the deadliest gynecological malignancies. As the prevalent post-transcriptional regulation, alternative polyadenylation (APA) plays a crucial role in various tumors. Here we identify that the APA regulator NUDT21 is upregulated in OC and promotes malignant progression. We further demonstrate that IGF2BP3 interacts with NUDT21, which suggests m6A modification could regulate APA processing. Mechanistically, IGF2BP3, recognizing the m6A-modified site in intron 32 of SPTBN1, recruits NUDT21 to promote the usage of the SPTBN1 proximal polyadenylation site (PAS), thus increasing the generation of short transcripts in OC cells. Intriguingly, the SPTBN1 long variant demonstrates tumor-suppressive properties, whereas the short variant enhances oncogenic activity in OC. Subsequently, we illustrate that the long isoform inhibits tumor growth and metastasis by binding to CDK1 and blocking the G2/M phase of the cell cycle. In conclusion, this study uncovers a previously unrecognized regulatory mechanism in OC, which could provide potential therapeutic strategies for OC.