Clear cell renal cell carcinoma has long posed a formidable challenge to oncologists due to its aggressive nature and resistance to conventional therapies. Despite advances in targeted treatments and immunotherapies, the molecular intricacies that underpin ccRCC progression remain incompletely understood. This latest research provides critical insights into how metabolic shifts within cancer cells are orchestrated to support unchecked proliferation and survival.

Central to this groundbreaking discovery is FUT8 (fucosyltransferase 8), an enzyme known primarily for its function in adding fucose sugars to glycoproteins—a modification known as core fucosylation. The research team led by Guo, Jiang, Wang, and colleagues has now demonstrated that FUT8’s influence extends far beyond glycosylation. They reveal its unexpected capacity to reprogram glycolytic metabolism, the process by which cancer cells convert glucose into energy and building blocks necessary for growth.

This metabolic reprogramming pivots around PKM2 (pyruvate kinase M2), a key glycolytic enzyme known to play a crucial role in cancer metabolism. Under normal physiological conditions, PKM2 regulates the final step of glycolysis, balancing energy production with anabolic processes. However, the research uncovers that FUT8 promotes an unusual biochemical modification—lactylation—on PKM2, dramatically altering its function and driving tumor cell metabolism towards favoring cancer progression.

Lactylation, a recently discovered post-translational modification, involves the addition of lactate-derived lactyl groups to lysine residues on proteins. While initially characterized in histones affecting gene expression, this study extends the concept by showing lactylation’s impact on metabolic enzymes, unveiling a new layer of regulatory complexity. In ccRCC cells, PKM2 lactylation enhances enzymatic activity and stability, fostering an environment ripe for accelerated glycolysis and tumor growth.

Employing an array of cutting-edge techniques including mass spectrometry, metabolic flux analysis, and in vivo tumor models, the researchers delineated the biochemical pathway by which FUT8 exerts this effect. They observed elevated FUT8 expression in ccRCC patient samples correlating with increased PKM2 lactylation levels, glycolytic gene signatures, and poor clinical prognosis. Functional experiments confirmed that silencing FUT8 diminished PKM2 lactylation, impairing glycolytic flux and slowing tumor progression.

Importantly, the study delineates a feed-forward loop wherein elevated FUT8 expression enhances the metabolic switch toward glycolysis, generating abundant lactate, which in turn facilitates further lactylation of PKM2. This self-reinforcing circuit creates a metabolic state that supports rapid tumor expansion and resistance to metabolic stress. Interrupting this loop offers a tantalizing therapeutic opportunity.

Current ccRCC treatments targeting vascular growth factors or immune checkpoints have limitations, often leading to relapse or resistance. The identification of the FUT8-PKM2-lactylation axis opens new avenues for metabolic intervention. By specifically targeting FUT8 enzymatic activity or interfering with PKM2 lactylation, it might be possible to disrupt cancer’s energy supply line, sensitizing tumors to existing therapies or halting progression.

The study also underscores the increasing significance of metabolic post-translational modifications as critical regulators of cancer biology. Beyond phosphorylation and acetylation, the role of novel modifications such as lactylation is emerging as a key contributor to the metabolic plasticity that characterizes aggressive tumors. These findings pivot future research towards exploring lactylation-centric therapeutic strategies.

Moreover, the researchers highlight that FUT8’s role may not be confined to ccRCC. Given the prevalence of metabolic reprogramming across multiple cancer types, FUT8-mediated lactylation could represent a broader oncogenic mechanism. Future studies are anticipated to investigate the role of this pathway in other malignancies, potentially expanding the clinical impact of these findings.

This research also opens questions about the interplay between tumor metabolism and the tumor microenvironment. Lactate has long been recognized as an immunosuppressive metabolite within the tumor milieu. By driving PKM2 lactylation, FUT8 may indirectly modulate immune evasion strategies, compounding the challenges of anti-cancer immunity. Understanding these interactions could inform combination therapies that address both tumor metabolism and immune modulation.

In conclusion, the discovery of FUT8’s ability to reprogram glycolytic metabolism through PKM2 lactylation unveils a sophisticated mechanism that fuels ccRCC progression. This work not only advances our molecular understanding of kidney cancer but also lays the foundation for the development of innovative metabolic therapies. As metabolic targeting gains traction in oncology, such studies are invaluable for charting new paths towards more effective, durable cancer treatments.

The implications of this research resonate far beyond the laboratory. By illuminating the metabolic underpinnings of ccRCC, this study offers hope for patients battling this aggressive cancer. Future translational efforts aimed at harnessing these insights could ultimately transform the clinical landscape, converting cancer’s metabolic vulnerabilities into therapeutic triumphs.

Subject of Research: The molecular mechanisms by which FUT8 reprograms glycolytic metabolism and promotes PKM2 lactylation to drive the progression of clear cell renal cell carcinoma.

Article Title: FUT8 reprograms glycolytic metabolism to promote PKM2 lactylation and drive clear cell renal cell carcinoma progression.

Article References:
Guo, Z., Jiang, H., Wang, X. et al. FUT8 reprograms glycolytic metabolism to promote PKM2 lactylation and drive clear cell renal cell carcinoma progression. Cell Death Discov. (2026). https://doi.org/10.1038/s41420-026-03013-1

Image Credits: AI Generated

DOI: https://doi.org/10.1038/s41420-026-03013-1

Clear cell renal cell carcinoma remains one of the most aggressive and treatment-resistant kidney cancers worldwide. Its hallmark lies not only in its distinct histopathological presentation but also in its well-orchestrated metabolic dysregulation, which fuels rapid tumor growth and survival under adverse microenvironmental conditions. The metabolic plasticity of ccRCC, especially its preference for aerobic glycolysis and altered gluconeogenesis, underscores the critical role of metabolic enzymes like FBP1. Until now, targeting these enzymes has been challenging due to the complexity of their regulatory networks and subcellular localizations.

The study conducted by Yang, Ma, Fan, and colleagues delves deeply into the mechanistic underpinnings of MLN4924’s anti-tumor efficacy. MLN4924, also known as pevonedistat, functions primarily as an inhibitor of the NEDD8-activating enzyme (NAE). By blocking the neddylation process, MLN4924 impairs the activity of cullin-RING E3 ubiquitin ligases (CRLs), pivotal mediators of ubiquitin-dependent protein degradation. This disruption stabilizes a variety of substrates previously targeted for proteasomal degradation, thereby modulating cellular pathways relevant to cancer progression.

Among the newly stabilized proteins identified, nuclear FBP1 emerged as a key mediator of tumor metabolism suppression upon MLN4924 treatment. FBP1, classically recognized for its cytoplasmic role in gluconeogenesis, exhibits a lesser-known nuclear localization with significant regulatory functions including transcriptional control and metabolic gene expression modulation. The researchers demonstrated that MLN4924 stabilizes FBP1 within the nucleus, attenuating glycolytic flux, and reinforcing metabolic checkpoints that hinder tumor proliferation.

Through comprehensive in vitro and in vivo analyses, the team verified that ccRCC cells treated with MLN4924 display a substantial decrease in aerobic glycolysis, manifesting as reduced glucose uptake and lactate production. These metabolic shifts culminate in inhibited tumor growth and increased apoptosis. Importantly, the stabilization of nuclear FBP1 by MLN4924 proved instrumental in mediating these metabolic alterations, establishing a direct causal link between FBP1 nuclear dynamics and cancer cell metabolic reprogramming.

The experimental framework leveraged advanced proteomic and metabolomic technologies to dissect the molecular echelon through which MLN4924 exerts its effects. Noteworthy was the observation that nuclear FBP1 acts as a metabolic checkpoint by repressing hypoxia-inducible factor 1-alpha (HIF-1α) target genes, which are heavily implicated in promoting the Warburg effect and sustaining proliferation in hypoxic tumor microenvironments. Consequently, nuclear FBP1 stabilization suppresses HIF-1α-driven transcriptional programs, undermining one of ccRCC’s central survival mechanisms.

Further mechanistic interrogation revealed that the inhibition of NAE by MLN4924 leads to reduced ubiquitination and proteasomal degradation of nuclear FBP1, prolonging its half-life and functionality in the nucleus. This novel insight into the post-translational regulation of FBP1 offers a fresh perspective on how metabolic enzyme localization and stability can be pharmacologically manipulated to achieve anti-cancer outcomes.

The translational implications of these findings are profound. MLN4924’s capacity to modulate cancer metabolism through stabilization of nuclear FBP1 suggests it could serve as a dual-function therapeutic: both disrupting protein turnover mechanisms and reprogramming tumor metabolism. Such multifaceted targeting is particularly valuable in resistant cancer phenotypes like ccRCC, where monotherapies often fall short due to adaptive cellular responses.

In preclinical models, systemic administration of MLN4924 significantly curtailed tumor burden without appreciable toxicity, bolstering the argument for clinical evaluation of MLN4924 in ccRCC patients. The therapeutic window outlined offers hope for integrating metabolism-centered interventions within standard oncology care, potentially in combination with existing targeted therapies or immunotherapies.

Beyond ccRCC, these insights may hold broader significance for other malignancies characterized by aberrant metabolic regulation and adaptive survival strategies. The nuclear functions of metabolic enzymes like FBP1, often overshadowed by their cytoplasmic roles, emerge as versatile intervention points for novel anti-cancer strategies.

However, several critical questions remain unanswered, inviting future research directions. How the nuclear localization signals of FBP1 are regulated, which E3 ligases are directly responsible for its ubiquitination, and whether MLN4924 influences other nuclear metabolic enzymes similarly awaits elucidation. Addressing these questions will refine our understanding of metabolic enzyme crosstalk within nuclear compartments and enhance therapeutic specificity.

Moreover, the potential resistance mechanisms to MLN4924 warrant thorough investigation. Cancer cells are notorious for their ability to bypass targeted interventions through compensatory pathways. Unraveling potential evasive responses could inform combinatorial approaches that sustain clinical efficacy and prevent relapse.

The study also emphasizes the importance of integrating multi-omics approaches to untangle cancer’s complexity. By combining proteomics, transcriptomics, and metabolomics, the researchers constructed a detailed map of MLN4924’s impact, highlighting the superiority of systems biology in guiding drug development and precision medicine.

In conclusion, the work by Yang et al. represents a landmark advancement in our comprehension of ccRCC metabolism and its pharmacological manipulation. The identification of MLN4924 as a stabilizer of nuclear FBP1 that effectively suppresses tumor metabolism and growth paves the way for metabolic enzyme-centered cancer therapies with distinct mechanisms and promising clinical potential. As metabolic reprogramming remains a cornerstone of oncogenic transformation, studies such as this reaffirm the power of targeting metabolic vulnerabilities to outmaneuver cancer’s adaptive arsenal.

Subject of Research: The study focuses on the therapeutic effects of MLN4924 on clear cell renal cell carcinoma, specifically its role in suppressing tumor metabolism and growth by stabilizing nuclear fructose-1,6-bisphosphatase 1 (FBP1).

Article Title: MLN4924 suppresses tumor metabolism and growth of clear cell renal cell carcinoma by stabilizing nuclear FBP1.

Article References:
Yang, Y., Ma, Y., Fan, S. et al. MLN4924 suppresses tumor metabolism and growth of clear cell renal cell carcinoma by stabilizing nuclear FBP1. Cell Death Discov. 11, 253 (2025). https://doi.org/10.1038/s41420-025-02426-8

Image Credits: AI Generated

DOI: https://doi.org/10.1038/s41420-025-02426-8