Lactylome analysis suggests lactylation-dependent mechanisms of metabolic adaptation in hepatocellular carcinoma

Deciphering novel enzymatic and non-enzymatic lysine lactylation in Salmonella

Lysine lactylation, a novel post-translational modification, is involved in multiple cellular processes. The role of lactylation remains largely unknown, especially in bacteria. Here, we identified 1090 lactylation sites on 469 proteins by mass spectrometry in Salmonella Typhimurium. Many proteins involved in metabolic processes, protein translation, and other biological functions are lactylated, with lactylation levels varying according to the growth phase or lactate supplementation. Lactylation is regulated by glycolysis, and inhibition of L-lactate utilization can enhance lactylation levels. In addition to the known lactylase in E. coli, the acetyltransferase YfiQ can also catalyse lactylation. More importantly, L-lactyl coenzyme A (L-La-CoA) and S,D-lactoylglutathione (LGSH) can directly donate lactyl groups to target proteins for chemical lactylation. Lactylation is involved in Salmonella invasion of eukaryotic cells, suggesting that lactylation is crucial for bacterial virulence. Collectively, we have comprehensively investigated protein lactylome and the regulatory mechanisms of lactylation in Salmonella, providing valuable insights into studying lactylation function across diverse bacterial species.

Turning sour into sweet: Lactylation modification as a promising target in cardiovascular health

Lactylation, a recently identified posttranslational modification (PTM), has emerged as a critical regulatory mechanism in cardiovascular diseases (CVDs). This PTM involves the addition of lactyl groups to lysine residues on histones and nonhistone proteins, influencing gene expression and cellular metabolism. The discovery of lactylation has revealed new directions for understanding metabolic and immune processes, particularly in the context of CVDs. This review describes the intricate roles of specific lactylated proteins and enzymes, such as H3K18, HMGB1, MCT1/4, and LDH, in the regulation of cardiovascular pathology. This study also highlights the unique impact of lactylation on myocardial hypertrophy and distinguishes it from other PTMs, such as SUMOylation and acetylation, underscoring its potential as a therapeutic target. Emerging drugs targeting lactate transporters and critical enzymes involved in lactylation offer promising avenues for novel CVD therapies. This review calls for further research to elucidate the mechanisms linking lactylation to CVDs, emphasizing the need for comprehensive studies at the molecular, cellular, and organismal levels to pave the way for innovative preventive, diagnostic, and treatment strategies in cardiovascular medicine.

G6PD lactylation is involved in regulating redox balance of boar sperm in low glucose extender

Glucose metabolism is an essential pathway that indirectly supports cellular redox homeostasis by providing reducing equivalents, such as NADPH, particularly in the highly specialized sperm. Sperm exhibit higher progressive motility in low glucose extender. However, the underlying mechanisms remain unclear. The objective of the present study was to investigate effect of low glucose on sperm metabolism and lactylation modification. After 3 h of incubation, low glucose had an effect on the redox state of boar semen in vitro, particularly in terms of the concentration of reactive oxygen species (ROS) and reductive products. Furthermore, glucose-6-phosphate dehydrogenase (G6PD) activity was significantly increased at low glucose condition, accompanied by increased lactate accumulation extracellularly. Meanwhile, protein lactylation levels were enhanced, with G6PD identified as one of lactylation proteins. In conclusion, low glucose incubation induced lactylation of G6PD, resulting in increased enzymatic activity that enhanced the pentose phosphate pathway (PPP), which in turn increased antioxidant capacity and maintained sperm motility in a low glucose environment. The research results provide valuable insights into the adaptation mechanisms of sperm to their environment and offer new perspectives and opportunities for reproductive biology research.

TPX2 lactylation is required for the cell cycle regulation and hepatocellular carcinoma progression

Targeting protein for Xklp2 (TPX2) is critical for mitosis and spindle assembly because of its control of Aurora kinase A (AURKA). However, the regulation of TPX2 activity and its subsequent effects on mitosis and cancer progression remain unclear. Here, we show that TPX2 is lactylated at K249 in hepatocellular carcinoma (HCC) tumour tissues and that this process is regulated by the lactylase CBP and the delactylase HDAC1. Lactate reduction via either shRNAs targeting lactate dehydrogenase A or the lactate dehydrogenase A inhibitor GSK2837808A decreases the level of TPX2 lactylation. Importantly, TPX2 lactylation is required for the cell cycle regulation and tumour growth. Mechanistically, TPX2 lactylation disrupts protein phosphatase 1 (PP1) binding to AURKA, enhances AURKA T288 phosphorylation, and facilitates the cell cycle progression. Overall, our study reveals a previously unappreciated role of TPX2 lactylation in regulating cell cycle progression and HCC tumorigenesis, exposing an important correlation between metabolic reprogramming and cell cycle regulation in HCC.

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.

Post-translational modifications and the reprogramming of tumor metabolism

Metabolic reprogramming occurs alongside tumor development. As cancers advance from precancerous lesions to locally invasive tumors and then to metastatic tumors, metabolic patterns exhibit distinct changes, including mutations in metabolic enzymes and modifications in the activity of metabolic regulatory proteins. Alterations in metabolic patterns can influence tumor evolution, either establishing or alleviating metabolic burdens and facilitating cancer growth. To fully understand how metabolic reprogramming helps tumors grow and find the metabolic activities that are most useful for treating tumors, we need to have a deeper understanding of how metabolic patterns are controlled as tumors grow. Post-translational modifications (PTMs), a critical mechanism in the regulation of protein function, can influence protein activity, stability, and interactions in several ways. In tumor cells, PTMs-mediated metabolic reprogramming is a crucial mechanism for adapting to the challenging microenvironment and sustaining fast growth. This article will deeply explore the intricate regulatory mechanism of PTMs on metabolic reprogramming and its role in tumor progression, with the expectation of providing new theoretical basis and potential targets for tumor treatment.

Supervised Machine Learning Models for Predicting Sepsis-Associated Liver Injury in Patients With Sepsis: Development and Validation Study Based on a Multicenter Cohort Study

BACKGROUND

Sepsis-associated liver injury (SALI) is a severe complication of sepsis that contributes to increased mortality and morbidity. Early identification of SALI can improve patient outcomes; however, sepsis heterogeneity makes timely diagnosis challenging. Traditional diagnostic tools are often limited, and machine learning techniques offer promising solutions for predicting adverse outcomes in patients with sepsis.

OBJECTIVE

This study aims to develop an explainable machine learning model, incorporating stacking techniques, to predict the occurrence of liver injury in patients with sepsis and provide decision support for early intervention and personalized treatment strategies.

METHODS

This retrospective multicenter cohort study adhered to the TRIPOD+AI (Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis, Extended for Artificial Intelligence) guidelines. Data from 8834 patients with sepsis in the Medical Information Mart for Intensive Care IV (MIMIC-IV) database were used for training and internal validation, while data from 4236 patients in the eICU-Collaborative Research Database (eICU-CRD) database were used for external validation. SALI was defined as an international normalized ratio >1.5 and total bilirubin >2 mg/dL within 1 week of intensive care unit admission. Nine machine learning models-decision tree, random forest (RF), extreme gradient boosting (XGBoost), light gradient boosting machine (LightGBM), support vector machine, elastic net, logistic regression, multilayer perceptron, and k-nearest neighbors-were trained. A stacking ensemble model, using LightGBM, XGBoost, and RF as base learners and Lasso regression as the meta-model, was optimized via 10-fold cross-validation. Hyperparameters were tuned using grid search and Bayesian optimization. Model performance was evaluated using accuracy, balanced accuracy, Brier score, detection prevalence, F1-score, Jaccard index, κ coefficient, Matthews correlation coefficient, negative predictive value, positive predictive value, precision, recall, area under the receiver operating characteristic curve (ROC-AUC), precision-recall AUC, and decision curve analysis. Shapley additive explanations (SHAP) values were used to quantify feature importance.

RESULTS

In the training set, LightGBM, XGBoost, and RF demonstrated the best performance among all models, with ROC-AUCs of 0.9977, 0.9311, and 0.9847, respectively. These models exhibited minimal variance in cross-validation, with tightly clustered ROC-AUC and precision-recall area under the curve distributions. In the internal validation set, LightGBM (ROC-AUC 0.8401) and XGBoost (ROC-AUC 0.8403) outperformed all other models, while RF achieved an ROC-AUC of 0.8193. In the external validation set, LightGBM (ROC-AUC 0.7077), XGBoost (ROC-AUC 0.7169), and RF (ROC-AUC 0.7081) maintained strong performance, although with slight decreases in ROC-AUC compared with the training set. The stacking model achieved ROC-AUCs of 0.995, 0.838, and 0.721 in the training, internal validation, and external validation sets, respectively. Key predictors-total bilirubin, lactate, prothrombin time, and mechanical ventilation status-were consistently identified across models, with SHAP analysis highlighting their significant contributions to the model's predictions.

CONCLUSIONS

The stacking ensemble model developed in this study yields accurate and robust predictions of SALI in patients with sepsis, demonstrating potential clinical utility for early intervention and personalized treatment strategies.

Lactylation-boosted polycomb repression of KLF4 elicits glycolysis in retinoblastoma: A positive feedback circuit between histone modifications

The perturbation of histone modification homeostasis is a hallmark of oncogene activation and tumor suppressor gene silencing. Howbeit, the intricate interplay among diverse histone modifications in the context of tumorigenesis is not fully understood. Herein, we unveil a positive feedback mechanism involving lactylation and methylation of histones, which is instrumental in the oncogenic progression of retinoblastoma. First, we pinpointed that the selective upregulation of SUZ12 leads to the upregulation of H3K27me3 modification in retinoblastoma, which is attributed to heightened levels of histone lactylation. Notably, the targeted suppression of SUZ12 has demonstrated significant therapeutic benefits in both in vitro and in vivo models of retinoblastoma. Furthermore, multi-omics analysis has identified Krüppel-like factor 4 (KLF4) as a key downstream effector of SUZ12. Mechanistically, SUZ12 is implicated in the enhancement of the H3K27me3 mark on the KLF4 promoter, thereby repressing its transcription. Intriguingly, the downregulation of KLF4 is associated with an upregulation of glycolysis and a concomitant accumulation of the onco-metabolite lactate, which in turn augments histone lactylation. In conclusion, we provide novel insights into the intricate interplay between lactylation and methylation of histones, shedding light on the epigenetic-metabolic reprogramming that underlies oncogene activation and tumor suppressor gene inactivation in cancer.

Lactate and lactylation in liver diseases: energy metabolism, inflammatory immunity and tumor microenvironment

Liver diseases pose a significant threat to human health. Lactate, a byproduct of glycolysis, serves various biological functions, including acting as an energy source, a signaling molecule, and a substrate for lactylation. Lactylation is a novel lactate-dependent post-translational modification that plays a role in tumor proliferation, the regulation of immune cell function, and the modulation of gene expression. In this paper, we summarize the roles of lactate and lactylation in energy metabolism, inflammatory immunity, and the tumor microenvironment, while also elucidating recent research advancements regarding lactate and lactylation in the context of hepatic fibrosis, non-alcoholic fatty liver disease, and hepatocellular carcinoma. Furthermore, lactate and lactylation are proposed as promising new targets for the treatment of liver diseases.

RACGAP1 and MKI67 are potential prognostic biomarker in hepatocellular carcinoma caused by HBV/HCV via lactylation

Introduction

Hepatocellular carcinoma (HCC) is recognized as the prime and lethal form of liver cancer caused by the hepatitis B virus (HBV) and hepatitis C virus (HCV) globally. Lactate is an end product of glycolysis that influences epigenetic expression through histone lactylation. While MKI67 and RACGAP1 play crucial roles in HBV- and HCV-related HCC. However, the role of lactylation-related genes (LRGs) effects in this context remains unclear. This study innovatively explored the role of LRGs in HBV/HCV-associated HCC, identifying novel biomarkers for diagnosis and prognosis.

Methods

The present study used various online databases for analysis, and the findings were validated via immunohistochemical (IHC) analysis of HCC patient samples (n=60).

Results

We identified six signature LRGs (ALB, G6PD, HMGA1, MKI67, RACGAP1, and RFC4) possess prognostic potential, correlation with immune infiltration, and lactylation-related pathways, providing novel insights into tumor microenvironment (TME) of HCC. Moreover, MKI67 and RACGAP1 were significantly associated with HBV- and HCV-related HCC. IHC confirmed these findings, with high expression of MKI67 and RACGAP1 was significantly linked with HBV/HCV-associated HCC compared to non-viral HCC. The expression is also significantly associated with key clinical variables.

Conclusion

Our results suggest that MKI67 and RACGAP1 could serve as promising biomarkers for detecting and predicting HCC caused by HBV/HCV via lactylation, opening a new direction for immune-targeted therapies.

A basigin antibody modulates MCTs to impact tumor metabolism and immunity

Lactate metabolism and signaling intricately intertwine in the context of cancer and immunity. Basigin, working alongside monocarboxylate transporters MCT1 and MCT4, orchestrates the movement of lactate across cell membranes. Despite their potential in treating formidable tumors, the mechanisms by which basigin antibodies affect basigin and MCTs remain unclear. Our research demonstrated that basigin positively modulates MCT activity. We subsequently developed a basigin antibody that converts basigin into a negative modulator, thereby suppressing lactate transport and enhancing anti-tumor immunity. Additionally, the antibody alters metabolic profiles in NSCLC-PDOs and T cells. Cryo-EM structural analysis and molecular dynamics simulations reveal that the extracellular Ig2 domain and transmembrane domain of basigin regulate MCT1 activity through an allosteric mechanism. The antibody decreases MCT1 transition rate by reducing the flexibility of basigin's Ig2 domain and diminishing interactions between basigin's transmembrane domain and MCT1. These findings underscore the promise of basigin antibodies in combating tumors by modulating metabolism and immunity, and the value of a common therapeutic subunit shared by multiple transporter targets.

Role of lysine lactylation in neoplastic and inflammatory pulmonary diseases (Review)

Protein lysine lactylation is a ubiquitous and post‑translational modification of lysine residues that involves the addition of a lactyl group on both histone and non‑histone proteins. This process plays a pivotal role in human health and disease and was first discovered in 2019. This epigenetic modification regulates gene transcription from chromatin or directly influences non‑histone proteins by modulating protein‑DNA/protein interactions, activity and stability. The dual functions of lactylation in both histone and non‑histone proteins establish it as a crucial mechanism involved in various cellular processes, such as cell proliferation, differentiation, immune and inflammatory responses and metabolism. Specific enzymes, referred to as 'writers' and 'erasers', catalyze the addition or removal of lactyl groups at designated lysine sites, thereby dynamically modulating lactylation through alterations in their enzymatic activities. The respiratory system has a remarkably intricate metabolic profile. Numerous pulmonary diseases feature an atypical transition towards glycolytic metabolism, which is linked to an overproduction of lactate, a possible substrate for lactylation. However, there has yet to be a comprehensive review elucidating the full impact of lactylation on the onset, progression and potential treatment of neoplastic and inflammatory pulmonary diseases. In the present review, an extensive overview of the discovery of lactylation and advancements in research on the existing lactylation sites were discussed. Furthermore, the review particularly investigated the potential roles and mechanisms of histone and non‑histone lactylation in various neoplastic and inflammatory pulmonary diseases, including non‑small cell lung cancers, malignant pleural effusion, pulmonary fibrosis, acute lung injury and asthma, to excavate the new therapeutic effects of post‑translational modification on various pulmonary diseases.

Lactylation and Ischemic Stroke: Research Progress and Potential Relationship

Ischemic stroke is caused by interrupted cerebral blood flow and is a leading cause of mortality and disability worldwide. Significant advancements have been achieved in comprehending the pathophysiology of stroke and the fundamental mechanisms responsible for ischemic damage. Lactylation, as a newly discovered post-translational modification, has been reported to participate in several physiological and pathological processes. However, research on lactylation and ischemic stroke is scarce. This review summarized the current function of protein lactylation in other diseases or normal physiological processes and explored their potential link with the pathophysiological process and the reparative mechanism of ischemic stroke. We proposed that neuroinflammation, regulation of metabolism, regulation of messenger RNA translation, angiogenesis, and neurogenesis might be the bridge linking lactylation and ischemic stroke. Our study provided a novel perspective for comprehending the role of protein lactylation in the pathophysiological processes underlying ischemic stroke. Lactylation might be a promising target in drug development of ischemic stroke.

The role of protein lactylation in brain health and disease: current advances and future directions

Lactate, the end product of glycolysis, plays a crucial role in cellular signaling and metabolism. The discovery of lactylation, a novel post-translational modification, has uncovered the role of lactate in regulating diseases, especially in the brain. Lactylation connects genetic encoding with protein function, thereby influencing key biological processes. Increasing evidence supports lactate-mediated lactylation as a critical modulator in neurological disorders. This review offers an overview of lactate metabolism and lactylation, highlighting recent advances in understanding the regulatory enzymes of lactylation and their role in the central nervous system. We investigate the impact of lactylation on brain dysfunctions, including neurodegenerative diseases, cerebrovascular disorders, neuroinflammation, brain tumors, and psychiatric conditions. Moreover, we highlight the therapeutic potential of targeting lactylation in treating brain disorders and outline key research gaps and future directions needed to advance this promising field.

Lactate drives senescence-resistant lineages in hepatocellular carcinoma via histone H2B lactylation of NDRG1

Hepatocellular carcinoma (HCC) treatment options remain limited despite advances in targeted therapies for molecularly-defined cancers. To address tumor heterogeneity, we reconstructed HCC clonal evolution through single-cell RNA sequencing trajectory analysis, identifying 902 signature genes across seven cellular states. Weighted gene co-expression network analysis of public HCC datasets revealed tumor-grade-associated modules and established a 14-gene prognostic model linked to clonal evolution. Central to this model is the LDHA-NDRG1 axis - two hypoxia-responsive regulators showing coordinated spatiotemporal expression patterns during cancer progression. Dual-expressing cell lineages correlated with poor prognosis and senescence resistance through LDHA-mediated lactylation of histone H2B at K58 on NDRG1, an epigenetic mechanism connecting metabolic reprogramming to senescence evasion. Therapeutically, dual inhibition of this axis extended survival in metastatic HCC murine models. Our findings reveal that lactate-driven epigenetic modification via the LDHA-NDRG1 axis creates a molecularly distinct subpopulation enabling senescence resistance, providing mechanistic insights into HCC heterogeneity. This work proposes a precision medicine strategy targeting lactylation-mediated epigenetic regulation, with implications for developing combination therapies and patient stratification based on clonal evolution patterns.

Lactylation orchestrates ubiquitin-independent degradation of cGAS and promotes tumor growth

Lactate extensively associates with metabolic reprogramming, signal transduction, and immune modulation. Nevertheless, the regulatory role of lactate in immune sensing of cytosolic DNA remains uncertain. Here, we report that lactate serves as an initiator to facilitate proteasomal degradation of cyclic GMP-AMP synthase (cGAS) independent of ubiquitin, thus repressing the production of interferon and contributing to tumor growth. Mechanistically, lactylation of K21 stimulates cGAS translocation from the nucleus to the proteasome for degradation, which is compromised by phosphorylation of PSMA4 S188 via disrupting its association with cGAS. Concurrently, lactylation of K415 rewires PIK3CB activity and impairs ULK1-driven phosphorylation of PSMA4 S188. Physiologically, lactylation of cGAS sustains tumor growth. Expression of cGAS correlates with the antitumor effect of the LDHA inhibitor FX11. Finally, the lactate-cGAS axis indicates a prognostic outcome of lung adenocarcinoma. Collectively, these findings not only put forth a mechanism of cGAS degradation but also unravel the clinical relevance of cGAS lactylation.

A Novel Signature Composed of Hypoxia, Glycolysis, Lactylation Related Genes to Predict Prognosis and Immunotherapy in Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death worldwide. The hypoxic microenvironment in HCC enhances glycolysis and co-directed lactate accumulation, which leads to increased lactylation. However, the exact biological pattern remains to be elucidated. Therefore, we sought to identify hypoxia-glycolysis-lactylation (HGL) prognosis-related signatures and validate this in vitro.

METHODS

Transcriptomic data of patients with HCC were collected from The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC), and Gene Expression Omnibus (GEO) databases. Differentially expressed HGL genes between HCC and normal tissues were obtained by DEseq2. The consensus clustering algorithm was employed to stratify patients into two distinct clusters. Subsequently, the single sample Gene Set Enrichment Analysis (ssGSEA), Tumor Immune Estimation Resource (TIMER) and Tumor Immune Dysfunction and Exclusion (TIDE) algorithms were utilized to assess immune infiltration and immune evasion. Least Absolute Shrinkage and Selection Operator (LASSO) and COX regression analysis were used to identify an HGL prognosis-related signature. Based on spatial transcriptome and histological data, we analyzed the expression of these genes in HCC and explored the function of Homer Scaffold Protein 1 (HOMER1) in HCC cells.

RESULTS

We identified 72 differentially expressed HGL genes and two HGL clusters. Cluster2, with better survival (p < 0.001), was significantly enriched in metabolic-related pathways. The HGL prognosis-related signature exhibited great predictive efficacy for patients in TCGA, ICGC, and GSE148355 databases (3-year area under the curve (AUC) = 0.822, 0.738, and 0.707, respectively). The elevated expression of HOMER1 in HCC was revealed by the combination of spatial transcriptome and histological data. Knocking down HOMER1 significantly inhibited the malignant progression of HCC cells.

CONCLUSIONS

We identified a signature with great predictive efficacy and discovered a gene, HOMER1, that influences the malignant progression of HCC with the potential to become a novel therapeutic target.

Lactylation in cancer progression and drug resistance

Lactate plays a crucial role as an energy substrate, metabolite, and signaling molecule in cancer. Lactate has long been considered a byproduct of glycolysis. Still, the lactate shuttle hypothesis has changed the lactate paradigm, revealing the implications of lactate in cellular metabolism and cellular communications that can transcend the compartment barrier and occur within and between different cells, tissues, and organs. Due to the Warburg effect, the tumor produces a large amount of lactate, thus creating a low-nutrition, hypoxic, and low-pH tumor microenvironment (TME). Consequently, immunosuppressive networks are built to acquire immune evasion potential and regulate tumor growth. Lactylation is a newly discovered post-translational modification of lysine residues with the capacity for transcriptional regulation via histone modification and modulation of non-histone protein functions, which links gene regulation to cellular metabolism by aberrant metabolism activity and epigenetic modification. There is growing evidence that lactylation plays a crucial role in cancer progression and drug resistance. Targeting lactylation enzymes or metabolic pathways has shown promising effects in suppressing cancer progression and drug resistance, highlighting the therapeutic potential of this modification. Therefore, in this review, we offer a systematic overview of lactate homeostasis in physiological and pathological processes as well as discuss the influence of lactylation in cancer progression and drug resistance and underlying molecular mechanisms, providing a theoretical basis for further research.

The mechanisms and effects of lactylation modification in different kinds of cancers

Lactylation, a recently identified post-translational modification, has garnered significant attention for its associations with various diseases, particularly its critical role in tumor progression and treatment. It is emerging as a potential clinical target. The elevated metabolic activity of cancer cells often leads to excessive lactate accumulation, a phenomenon termed the "Warburg effect", which is a hallmark of the tumor microenvironment. Recent research reveals that lactate is not merely a metabolic byproduct but also serves as a substrate for protein lactylation, influencing tumor development by regulating cellular signaling, gene expression, and immune responses. This dual role has become a focal point for scientists and clinicians seeking novel therapeutic strategies targeting lactate-related pathways. Despite growing interest, the detailed mechanisms and therapeutic applications of lactylation across different cancer types remain inadequately explored. This review synthesizes current findings on lactylation mechanisms in various tumors, highlights potential therapeutic targets, and offers new perspectives to advance cancer treatment.

Post-translational acylation of proteins in cardiac hypertrophy

Acylations are post-translational modifications in which functional groups are attached to amino acids on proteins. Most acylations (acetylation, butyrylation, crotonylation, lactylation, malonylation, propionylation and succinylation) involve lysine but cysteine (palmitoylation) and glycine (myristoylation) residues can also be altered. Acylations have important roles in physiological and pathophysiological processes, including cardiac hypertrophy and related cardiovascular diseases. These post-translational modifications influence chromatin architecture, transcriptional regulation and metabolic pathways, thereby affecting cardiomyocyte function and pathology. The dynamic interaction between these acylations and their regulatory enzymes, such as histone acetyltransferases, histone deacetylases and sirtuins, underscores the complexity of cellular homeostasis and pathological processes. Emerging evidence highlights the therapeutic potential of targeting acylations to modulate enzyme activity and metabolite levels, offering promising avenues for novel treatments. In this Review, we explore the diverse mechanisms through which acylations contribute to cardiac hypertrophy, highlighting the complexity and potential therapeutic targets in this regulatory network.

Integrated multi-omics analysis and machine learning refine molecular subtypes and clinical outcome for hepatocellular carcinoma

The high morbidity and mortality of hepatocellular carcinoma (HCC) impose a substantial economic burden on patients' families and society, and the majority of HCC patients are detected at advanced stages and experience poor therapeutic outcomes, whereas early-stage patients exhibit the most favorable prognosis following radical treatment. In this study, we utilized a computational framework to integrate multi-omics data from HCC patients using the latest 10 different clustering algorithms, which were then employed a diverse set of 101 combinations derived from 10 different machine learning algorithms to develop a consensus machine learning-based signature (CMLBS). Using multi-omics consensus clustering, we distinguished two cancer subtypes (CSs) of HCC, and found that CS2 patients exhibited superior overall survival (OS) outcomes. In TCGA-LIHC, ICGC-LIRI, and multiple immunotherapy cohorts, low-CMLBS patients demonstrated favorable clinical outcomes and enhanced responsiveness to immunotherapy. Encouragingly, we observed that the high-CMLBS patients may exhibit increased sensitivity to Alpelisib, AZD7762, BMS-536,924, Carmustine, and GDC0810, whereas they may demonstrate reduced sensitivity to Axitinib, AZD6482, AZD8055, Entospletinib, GSK269962A, GSK1904529A, and GSK2606414, suggesting that CMLBS may contribute to the selection of chemotherapeutic agents for HCC patients. Therefore, in-depth examination of data from multi-omics data can provide valuable insights and contribute to the refinement of the molecular classification of HCC. In addition, the CMLBS model demonstrates potential as a screening tool for identifying HCC patients who may derive benefit from immunotherapy, and it possesses practical utility in the clinical management of HCC.

PBertKla: a protein large language model for predicting human lysine lactylation sites

BACKGROUND

Lactylation is a newly discovered type of post-translational modification, primarily occurring on lysine (K) residues of both histones and non-histones to exert diverse effects on target proteins. Research has shown that lysine lactylation (Kla) modification is ubiquitous in different cells and participates in the determination of cell function and fate, as well as in the initiation and progression of various diseases. Precise identification of Kla sites is fundamental for elucidating their biological functions and uncovering their application potential.

RESULTS

Here, we proposed a novel human Kla site predictor (named PBertKla) through curating a reliable benchmark dataset with proper sample length and sequence identity threshold to train a protein large language model with optimal hyperparameters. Extensive experimental results consistently demonstrated that our model possessed robust human Kla site prediction ability, achieving an AUC (area under receiver operating characteristic curve) value of over 0.880 on the independent validation data. Feature visualization analysis further validated the effectiveness of in feature learning and representation from Kla sequences. Moreover, we benchmarked PBertKla against other cutting-edge models on an independent testing dataset from different sources, highlighting its superiority and transferability.

CONCLUSIONS

All results indicated that PBertKla excelled as an automatic predictor of human Kla sites, and it would advance the investigation of lactylation modifications and their significance in health and disease.

Global Profiling of Lactylation Proteomics and Specific Lactylated Site Validation in Rheumatoid Arthritis Patients

Protein lactylation is a novel post-translational modification that has rarely been investigated in rheumatoid arthritis (RA). This study aimed to explore lactylation proteomics in RA patients and validate sorted candidate lactylation sites. Synovial tissues from ten RA and six osteoarthritis (OA) patients were subjected to lactylation proteomics via affinity enrichment and LC-MS/MS. Four candidate lactylated modification sites were validated by immunoprecipitation. Totally, 566 sites and 250 proteins with lactylated modifications in RA patients and 548 sites and 220 proteins with lactylated modifications in OA patients were identified. By comparison, 24 upregulated but 2 downregulated lactylated modification sites and 18 upregulated but 1 downregulated lactylated modification protein were discovered in RA patients versus OA patients. The dysregulated lactylated proteins were mainly enriched in biological processes such as positive regulation of plasma membrane repair by GO analysis; pathways such as neutrophil extracellular trap formation by KEGG analysis; and two metabolism-related items by COG/KOG analysis. Immunoprecipitation confirmed that FTH1-K69la (P = 0007) and PKM2-K166la (P = 0.003), but not ANXA2-K115la (P = 0.127) or ANXA5-K76la (P = 0.361), were more abundant in RA patients versus OA patients. Moreover, FTH1-K69la was positively correlated with erythrocyte sedimentation rate (ESR) in RA patients (P = 0.037). Conclusively, this study describes a general landscape of lactylation proteomics in the RA.

Integrated multi-omics analysis reveals the functional and prognostic significance of lactylation-related gene PRDX1 in breast cancer

Background

Breast cancer (BRCA) is a significant threat to women's health worldwide, and its progression is closely associated with the tumor microenvironment and gene regulation. Lactylation modification, as a key epigenetic mechanism in cancer biology, has not yet been fully elucidated in the context of BRCA. This study examines the regulatory mechanisms of lactylation-related genes (LRGs), specifically PRDX1, and their prognostic significance in BRCA.

Methods

We integrated data from multiple databases, including Genome-Wide Association Study (GWAS) summary statistics, single-cell RNA sequencing, spatial transcriptomics, and bulk RNA sequencing data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Using Summary-based Mendelian Randomization (SMR) analysis, we identified LRGs associated with BRCA and comprehensively analysed the expression patterns of PRDX1, cell-cell communication networks, and spatial heterogeneity. Furthermore, we constructed and validated a prognostic model based on the gene expression profile of PRDX1-positive monocytes, evaluating it through Cox regression and LASSO regression analyses.

Results

PRDX1 was identified as a key LRG significantly associated with BRCA risk (p_SMR = 0.0026). Single-cell RNA sequencing analysis revealed a significant upregulation of PRDX1 expression in monocytes, with enhanced cell-cell communication between PRDX1-positive monocytes and fibroblasts. Spatial transcriptomics analysis uncovered heterogeneous expression of PRDX1 in the tumor nest regions, highlighting the spatial interaction between PRDX1-positive monocytes and fibroblasts. The prognostic model constructed based on the gene expression profile of PRDX1-positive monocytes demonstrated high accuracy in predicting patient survival in both the training and validation cohorts. High-risk patients exhibited immune-suppressive microenvironment characteristics, including reduced immune cell infiltration and upregulation of immune checkpoint gene expression.

Conclusion

This study reveals the key role of PRDX1 in BRCA progression, mainly through the regulation of the tumor microenvironment and immune escape mechanisms. The survival prediction model based on PRDX1 shows robust prognostic potential, and future research should focus on integrating PRDX1 with other biomarkers to enhance the precision of personalised medicine.

The role of protein lactylation: A kaleidoscopic post-translational modification in cancer

The recently discovered lysine lactylation represents a critical post-translational modification with widespread implications in epigenetics and cancer biology. Initially identified on histones, lysine lactylation has been also described on non-histone proteins, playing a pivotal role in transcriptional activation, protein function, and cellular processes. Two major sources of the lactyl moiety have been currently distinguished: L-lactyl-CoA (precursor of the L-lactyl moiety) and S-D-lactylglutathione (precursor of the D-lactyl moiety), which enable enzymatic and non-enzymatic mechanisms of lysine lactylation, respectively. Although the specific writers, erasers, and readers of this modification are still unclear, acetyltransferases and deacetylases have been proposed as crucial mediators of lysine lactylation. Remarkably, lactylation exerts significant influence on critical cancer-related pathways, thereby shaping cellular behavior during malignant transformation and the metastatic cascade. Hence, as recent insights into lysine lactylation underscore its growing potential in tumor biology, targeting this modification is emerging as a significant opportunity for cancer treatment.

Potential of lactylation as a therapeutic target in cancer treatment (Review)

Post‑translational modifications (PTMs) of proteins influence their functionality by altering the structure of precursor proteins. These modifications are closely linked to tumor progression through the regulation of processes such as cell proliferation, apoptosis, angiogenesis and invasion. Tumors produce large amounts of lactic acid through aerobic glycolysis. Lactic acid not only serves an important role in cell metabolism, but also serves an important role in cell communication. Lactylation, a PTM involving lactate and lysine residues as substrates, serves as an epigenetic regulator that modulates intracellular signaling, gene expression and protein function, thereby serving a crucial role in tumorigenesis and progression. The identification of lactylation provides a key breakthrough in elucidating the interaction between tumor metabolic reprogramming and epigenetic modification. The present review primarily summarizes the occurrence of lactylation, its effect on tumor progression, drug resistance, the tumor microenvironment and gut microbiota, and its potential as a therapeutic target for cancer. The aim of the present review was to provide novel strategies for potential cancer therapies.

Lactylation and regulated cell death

Lactylation, a newly identified post-translational modification, entails the attachment of lactate to lysine residues within proteins, profoundly modulating diverse cellular mechanisms underlying regulated cell death (RCD). This modification encompasses two primary categories: histone lactylation and non-histone lactylation. Histone lactylation assumes a pivotal regulatory function in the RCD process, primarily by modulating the transcriptional landscape of genes implicated in cell death. In contrast, non-histone lactylation exerts its influence by targeting transferases, transcription, cell cycle progression, death pathways, and metabolic processes that are intricately involved in RCD. This review provides a comprehensive overview of recent breakthroughs in understanding how lactylation regulates RCD, while also offering insights into potential avenues for future research, thereby deepening our comprehension of cellular fate determination.

The role of lactylation in virology

Lactylation, a novel post-translational protein modification, is increasingly recognized for its widespread occurrence on lysine residues in both histone and non-histone proteins. Recent research has primarily focused on its implications in specific human diseases, particularly cancer progression, metabolic disorders, neurodegenerative diseases, and immune responses. However, it is crucial to acknowledge the significant roles played by viruses as pathogens in both clinical and veterinary medicine, as well as in zoological and phytopathological studies. This review highlights the latest advancements in understanding the mechanisms underlying lactylation and its regulation, emphasizing the role of lactylation in certain viruses. We discuss its involvement in essential biological functions, the pathogenic mechanisms of various viruses, host-virus interactions, and practical applications, including the potential for lactylation to serve as a therapeutic target in disease pathogenesis. Exploring the interactions between viruses and lactylation presents a promising research direction that may help refine the emerging concept of lactylation.

Muscle-derived small extracellular vesicles induce liver fibrosis during overtraining

The benefits of exercise for metabolic health occur in a dose-dependent manner. However, the adverse effects of overtraining and their underlying mechanisms remain unclear. Here, we show that overtraining induces hepatic fibrosis. Mechanistically, we find that excessive lactate accumulation in skeletal muscle leads to the lactylation of SH3 domain-containing 3 (SORBS3), triggering its liquid-liquid phase separation (LLPS). LLPS of SORBS3 enhances its interaction with flotillin 1 and selectively facilitates the sorting of F-box protein 2 (FBXO2) into small extracellular vesicles, referred to as "lactate bodies." Lactate bodies induce hepatocyte apoptosis followed by hepatic stellate cell activation via myeloid cell leukemia sequence 1 (MCL1)-BAX/BAK signaling. Inhibition of SORBS3 lactylation or FBXO2 disrupts lactate bodies formation and alleviates overtraining-triggered liver fibrosis. Likewise, reduction of muscle lactate bodies formation by salidroside attenuates overtraining-induced liver fibrosis. Collectively, we identify a process by which overtraining induces hepatic fibrosis, highlighting a potential therapeutic target for liver health.

Targeting lactylation and the STAT3/CCL2 axis to overcome immunotherapy resistance in pancreatic ductal adenocarcinoma

Metabolic reprogramming in pancreatic ductal adenocarcinoma (PDAC) fosters an immunosuppressive tumor microenvironment (TME) characterized by elevated lactate levels, which contribute to immune evasion and therapeutic resistance. In this issue of the JCI, Sun, Zhang, and colleagues identified nonhistone ENSA-K63 lactylation as a critical regulator that inactivates PP2A, activates STAT3/CCL2 signaling, recruits tumor-associated macrophages (TAMs), and suppresses cytotoxic T cell activity. Targeting ENSA-K63 lactylation or CCL2/CCR2 signaling reprograms the TME and enhances the efficacy of immune checkpoint blockade (ICB) in PDAC preclinical models. This work provides critical insights into the metabolic-immune crosstalk in PDAC and highlights promising therapeutic strategies for overcoming immune resistance and improving patient outcomes.

Epigenetics in evolution and adaptation to environmental challenges: pathways for disease prevention and treatment

Adaptation to challenging environmental conditions is crucial for the survival/fitness of all organisms. Alongside genetic mutations that provide adaptive potential during environmental challenges, epigenetic modifications offer dynamic, reversible, and rapid mechanisms for regulating gene expression in response to environmental changes in both evolution and daily life, without altering DNA sequences or relying on accidental favorable mutations. The widespread conservation of diverse epigenetic mechanisms - like DNA methylation, histone modifications, and RNA interference across diverse species, including plants - underscores their significance in evolutionary biology. Remarkably, environmentally induced epigenetic alterations are passed to daughter cells and inherited transgenerationally through germline cells, shaping offspring phenotypes while preserving adaptive epigenetic memory. Throughout anthropoid evolution, epigenetic modifications have played crucial roles in: i) suppressing transposable elements and viral genomes intruding into the host genome; ii) inactivating one of the X chromosomes in female cells to balance gene dosage; iii) genetic imprinting to ensure expression from one parental allele; iv) regulating functional alleles to compensate for dysfunctional ones; and v) modulating the epigenome and transcriptome in response to influence from the gut microbiome among other functions. Understanding the interplay between environmental factors and epigenetic processes may provide valuable insights into developmental plasticity, evolutionary dynamics, and disease susceptibility.

ABCF1-K430-Lactylation promotes HCC malignant progression via transcriptional activation of HIF1 signaling pathway

Lysine lactylation plays critical roles in various diseases, including cancer. Our previous study showed that lactylation of non-histone ABCF1 may be involved in hepatocellular carcinoma (HCC) progression. In this study, we evaluated the prognostic value of ABCF1-K430la in HCC using immunohistochemical staining and performed amino acid point mutations, multi-omics crossover, and biochemical experiments to investigate its biological role and underlying mechanism. Additionally, we performed molecular docking on lactylation sites. ABCF1-K430la was highly expressed in HCC tissues and correlated with poor patient prognosis. Functionally, ABCF1-K430la promoted HCC growth and lung metastasis. Mechanistically, upon lactylation, E2 ubiquitin ligase activity of ABCF1 remained unaffected, and ABCF1 entered the nucleus, bound to the KDM3A promoter to upregulate its expression, and activated the KDM3A-H3K9me2-HIF1A axis, challenging the notion that ABCF1 functions exclusively in cytoplasmic protein translation. Notably, we discovered the existence of a lactate-ABCF1(430Kla)-HIF1A-lactate in HCC. A small-molecule drug screen targeting ABCF1-K430la revealed that tubuloside A inhibits ABCF1-K430la and suppresses HCC development. These findings demonstrate that elevated ABCF1-K430la expression promotes HCC development, suggesting it as a potential prognostic biomarker and therapeutic target for HCC.

HDAC2-Mediated METTL3 Delactylation Promotes DNA Damage Repair and Chemotherapy Resistance in Triple-Negative Breast Cancer

The current treatment of triple-negative breast cancer (TNBC) is still primarily based on platinum-based chemotherapy. However, TNBC cells frequently develop resistance to platinum and experience relapse after drug withdrawal. It is crucial to specifically target and eliminate cisplatin-tolerant cells after platinum administration. Here, it is reported that upregulated N 6-methyladenosine (m6A) modification drives the development of resistance in TNBC cells during cisplatin treatment. Mechanistically, histone deacetylase 2 (HDAC2) mediates delactylation of methyltransferase-like 3 (METTL3), facilitating METTL3 interaction with Wilms'-tumor-1-associated protein and subsequently increasing m6A of transcript-associated DNA damage repair. This ultimately promotes cell survival under cisplatin. Furthermore, pharmacological inhibition of HDAC2 using Tucidinostat can enhance the sensitivity of TNBC cells to cisplatin therapy. This study not only elucidates the biological function of lactylated METTL3 in tumor cells but also highlights its negative regulatory effect on cisplatin resistance. Additionally, it underscores the nonclassical functional mechanism of Tucidinostat as a HDAC inhibitor for improving the efficacy of cisplatin against TNBC.

The emerging role of protein L-lactylation in metabolic regulation and cell signalling

L-Lactate has emerged as a crucial metabolic intermediate, moving beyond its traditional view as a mere waste product. The recent discovery of L-lactate-driven protein lactylation as a post-translational modification has unveiled a pathway that highlights the role of lactate in cellular signalling. In this Perspective, we explore the enzymatic and metabolic mechanisms underlying protein lactylation and its impacts on both histone and non-histone proteins in the contexts of physiology and diseases. We discuss growing evidence suggesting that this modification regulates a wide range of cellular functions and is involved in various physiological and pathological processes, such as cell-fate determination, development, cardiovascular diseases, cancer and autoimmune disorders. We propose that protein lactylation acts as a pivotal mechanism, integrating metabolic and signalling pathways to enable cellular adaptation, and highlight its potential as a therapeutic target in various diseases.

Lactate promotes the epithelial-mesenchymal transition of liver cancer cells via TWIST1 lactylation

Elevated lactate levels increase the risk of liver cancer progression. However, the mechanisms by which lactate promotes liver cancer progression remain poorly understood. Epithelial-mesenchymal transition (EMT), characterized by the loss of epithelial cells polarity and cell-cell adhesion, leading to the acquisition of mesenchymal-like phenotypes, is widely recognized as a key contributor to liver cancer progression. TWIST1 (Twist Family BHLH Transcription Factor 1) plays a central role in inducing EMT. Here, we investigated the role of lactate in promoting EMT in liver cancer and the underlying regulatory mechanisms. High levels of lactate significantly promoted EMT progression in liver cancer cells. Mechanistically, lactate-induced lactylation of TWIST1 in vivo and in vitro. Mutation assay confirmed that Lysine 33 (K33) is the major site of TWIST1 lactylation. Moreover, cell fractionation & luciferase reporter assay results identified that TWIST1-K33R mutant impaired the EMT process via inhibiting nuclear import and the transcriptional activity. Thus, our findings provide novel insights into the regulatory role of lactate in EMT in liver cancer pathogenesis. Additionally, targeting of lactate-driven lactylation of TWIST1 may boost the therapeutic strategy for liver cancer.

Emerging roles of lysine lactyltransferases and lactylation

Given its various roles in cellular functions, lactate is no longer considered a waste product of metabolism and lactate sensing is a pivotal step in the transduction of lactate signals. Lysine lactylation is a recently identified post-translational modification that serves as an intracellular mechanism of lactate sensing and transfer. Although acetyltransferases such as p300 exhibit general acyl transfer activity, no bona fide lactyltransferases have been identified. Recently, the protein synthesis machinery, alanyl-tRNA synthetase 1 (AARS1), AARS2 and their Escherichia coli orthologue AlaRS, have been shown to be able to sense lactate and mediate lactyl transfer and are thus considered pan-lactyltransferases. Here we highlight the mechanisms and functions of these lactyltransferases and discuss potential strategies that could be exploited for the treatment of human diseases.

Lactylation-Driven HECTD2 Limits the Response of Hepatocellular Carcinoma to Lenvatinib

Drug resistance remains a major hurdle for the therapeutic efficacy of lenvatinib in hepatocellular carcinoma (HCC). However, the underlying mechanisms remain largely undetermined. Unbiased proteomic screening is performed to identify the potential regulators of lenvatinib resistance in HCC. Patient-derived organoids, patient-derived xenograft mouse models, and DEN/CCl4 induced HCC models are constructed to evaluate the effects of HECTD2 both in vitro and in vivo. HECTD2 is found to be highly expressed in lenvatinib-resistant HCC cell lines, patient tissues, and patient-derived organoids and xenografts. In vitro and in vivo experiments demonstrated that overexpression of HECTD2 limits the response of HCC to lenvatinib treatment. Mechanistically, HECTD2 functions as an E3 ubiquitin ligase of KEAP1, which contributes to the degradation of KEAP1 protein. Subsequently, the KEAP1/NRF2 signaling pathway initiates the antioxidative response of HCC cells. Lactylation of histone 3 on lysine residue 18 facilitates the transcription of HECTD2. Notably, a PLGA-PEG nanoparticle-based drug delivery system is synthesized, effectively targeting HECTD2 in vivo. The NPs achieved tumor-targeting, controlled-release, and biocompatibility, making them a promising therapeutic strategy for mitigating lenvatinib resistance. This study identifies HECTD2 as a nanotherapeutic target for overcoming lenvatinib resistance, providing a theoretical basis and translational application for HCC treatment.

A Potassium Channel-Related Signature for Prognosis and Immune Landscape Prediction of Hepatocellular Carcinoma

Potassium channel-related genes (PCRGs) play an important role in hepatocellular carcinoma (HCC) development, recurrence, and immunotherapy tolerance. We aimed to develop a new prognostic model associated with PCRGs that can be used for prognosis and immunotherapy prediction in HCC patients. The transcriptional profiles and clinical data related to HCC were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Differentially expressed PCRGs were identified using the "edgeR" package. Prognostic model associated with PCRGs were constructed using univariate analysis, least absolute shrinkage and selection operator (LASSO), and multivariate regression analysis. The prognostic value of the model was evaluated through Kaplan-Meier (K-M) survival analysis and receiver operating characteristic (ROC) curves. Additionally, the tumor immune microenvironment was assessed using single sample gene set enrichment analysis (ssGSEA) and the CIBERSORT algorithm. Finally, potential drugs targeting signature genes were predicted. We successfully constructed a prognostic signature based on PCRGs, and the prognostic results were superior in the low-risk group. The nomogram demonstrated satisfactory predictive performance in estimating overall survival (OS) in HCC patients. The results of immune cell infiltration and predictions of immunotherapy response revealed that the low-risk group exhibited a more favorable response to immunotherapy. In addition, signature gene expression was significantly correlated with antitumor drug sensitivity. In conclusion, the characteristics of PCRGs serve as valuable tools for accurately assessing the prognosis and tumor microenvironment of HCC patients. Additionally, PCRGs markers can facilitate precision therapy in HCC management.

Histone lactylation drives liver cancer metastasis by facilitating NSF1-mediated ferroptosis resistance after microwave ablation

Insufficient microwave ablation (IMWA) is linked to aggressive hepatocellular carcinoma (HCC) progression. An increase in lactate levels after sublethal heat stress (HS) has been confirmed in HCC. However, the role of lactate-related histone lactylation in the progression of HCC caused by sublethal HS remains unclear. Here, we found that the metastatic potential of HCC increased in a lactate-dependent manner after IMWA. Moreover, sublethal HS triggered an increase in H3K18la modification, as validated in a cell-derived xenograft mouse model and human HCC samples. By performing an integrated analysis of proteomic and transcriptomic profiles, we revealed that HCC cells exhibited increased intracellular iron ion homeostasis and developed resistance to platinum-based drugs after exposure to sublethal HS. We subsequently integrated proteomic and transcriptomic data with H3K18la-specific chromatin immunoprecipitation (ChIP) sequencing to identify candidate genes involved in sublethal heat treatment-induced HCC cell metastasis. Mechanically, an increase in H3K18la modification enhanced the transcriptional activity of NFS1 cysteine desulfurase (NFS1), a key player in iron‒sulfur cluster biosynthesis, thereby reducing the susceptibility of HCC to ferroptosis after IMWA. Knocking down NFS1 diminished the metastatic potential of sublethally heat-treated HCC cells. Additionally, NFS1 deficiency exhibited a synergistic effect with oxaliplatin, leading to the significant inhibition of the metastatic capability of HCC cells both in vitro and in vivo, regardless of sublethal HS treatment. In conclusion, our study revealed the oncogenic role of histone lactylation in HCC after IMVA. We also bridged histone lactylation with ferroptosis, providing novel therapeutic targets for HCC following microwave ablation, particularly when combined with oxaliplatin-based chemotherapy.

Functions and mechanisms of non-histone post-translational modifications in cancer progression

Protein post-translational modifications (PTMs) refer to covalent and enzymatic alterations to folded or nascent proteins during or after protein biosynthesis to alter the properties and functions of proteins. PTMs are modified in a variety of types and affect almost all aspects of cell biology. PTMs have been reported to be involved in cancer progression by influencing multiple signaling pathways. The mechanism of action of histone PTMs in cancer has been extensively studied. Notably, evidence is mounting that PTMs of non-histone proteins also play a vital role in cancer progression. In this review, we provide a systematic description of main non-histone PTMs associated with cancer progression, including acetylation, lactylation, methylation, ubiquitination, phosphorylation, and SUMOylation, based on recent studies.

Lactylation: A Novel Epigenetic Regulator of Cellular Senescence

Cellular senescence is the basic unit of organismal aging, a complicated biological process involving several cell types and tissues. It is also an important mechanism by which the body responds to damage and potential carcinogenesis. However, excessive or abnormal cellular senescence can lead to tissue functional degradation and the occurrence of diseases. In recent years, the role of epigenetic modifications in cellular senescence has received extensive attention. Lactylation, a novel post-translational modification derived from lactate, has recently gained significant attention as a key factor in cellular metabolism and epigenetic regulation, gradually demonstrating its importance in the regulation of cellular senescence. This review emphasizes the bidirectional causal relationship between lactylation and cellular senescence, highlighting its potential as a therapeutic target for aging-related diseases.

Lactylation of LSD1 is an acquired epigenetic vulnerability of BRAFi/MEKi-resistant melanoma

BRAFV600E mutant melanomas treated with BRAF inhibitor (BRAFi) and MEK inhibitor (MEKi) almost invariably develop drug resistance, accompanied by restored glucose metabolism. How resumed glycolysis controls acquired resistance remains unknown. Here, we identify that lysine-specific demethylase 1 (LSD1) lactylation, induced by re-accumulated lactate in both human and murine BRAFi/MEKi-resistant melanoma cells, selectively drives survival via epigenetic reprogramming. Mechanistically, lactylation of LSD1 promotes its interaction with Fos-related antigen 1 (FosL1), preventing its degradation by E3 ligase tripartite-motif-containing protein 21 (TRIM21) and selectively enhancing its genomic enrichment. We further demonstrate that lactylated LSD1 co-directs gene transcription with FosL1 to repress ferroptosis via interfering with transferrin receptor protein 1 (TFRC)-mediated iron uptake. LSD1 inhibition activates ferroptosis, resulting in drastic regression of drug-resistant murine melanoma when combined with immunotherapy. Our results highlight a crucial role of metabolic rewiring-induced epigenetic reprogramming as a bypass resistance mechanism in BRAFi/MEKi-resistant melanoma, providing a therapeutically actionable strategy to overcome resistance to targeted therapy and immunotherapy.

Histone lactylation enhances GCLC expression and thus promotes chemoresistance of colorectal cancer stem cells through inhibiting ferroptosis

Colorectal cancer stem cells (CCSCs) play a critical role in mediating chemoresistance. Lactylation is a post-translational modification induced by lactate that regulates gene expression. However, whether lactylation affects the chemoresistance of CCSCs remains unknown. Here, we demonstrate that histone lactylation enhances CCSC chemoresistance both in vitro and in vivo. Furthermore, our findings showed that p300 catalyzes the lactylation of histone H4 at K12, whereas HDAC1 facilitates its delactylation in CCSCs. Notably, lactylation at H4K12 (H4K12la) upregulates GCLC expression and inhibits ferroptosis in CCSCs, and the inhibition of p300 or LDHA decreases H4K12la levels, thereby increasing the chemosensitivity of CCSCs. Additionally, the GCLC inhibitor BSO promotes ferroptosis and sensitizes CCSCs to oxaliplatin. Taken together, these findings suggest that histone lactylation upregulates GCLC to inhibit ferroptosis signaling, thus enhancing CCSC chemoresistance. These findings provide new insights into the relationship between cellular metabolism and chemoresistance and suggest potential therapeutic strategies targeting p300, LDHA, and GCLC. We showed that histones H4K12 lactylation promoted chemoresistance in CSCs. p300 catalyzes the lactylation of histone H4 at K12, HDAC1 inhibits the histone lactylation at the same site. H4K12la in CSCs regulates the expression of the ferroptosis-related gene GCLC, thereby inhibiting ferroptosis and leading to chemoresistance. Targeting the p300, LDHA, or GCLC may be overcome tumor chemoresistance.

The lactylation modification of proteins plays a critical role in tumor progression

Lactylation modifications have been shown to be a novel type of protein post-translational modifications (PTMs), providing a new perspective for understanding the interaction between cellular metabolic reprogramming and epigenetic regulation. Studies have shown that lactylation plays an important role in the occurrence, development, angiogenesis, invasion and metastasis of tumors. It can not only regulate the phenotypic expression and functional polarization of immune cells, but also participate in the formation of tumor drug resistance through a variety of molecular mechanisms. In this review, we review the latest research progress of lactylation modification in tumors, focusing on its mechanism of action in angiogenesis, immune cell regulation in tumor microenvironment (TME), and tumor drug resistance, aiming to provide a theoretical basis and research ideas for the discovery of new therapeutic targets and methods. Through the in-depth analysis of lactylation modification, it is expected to open up a new research direction for tumor treatment and provide potential strategies for overcoming tumor drug resistance and improving clinical efficacy.

Pain, lactate, and anesthetics: intertwined regulators of tumor metabolism and immunity

Patients with advanced cancer frequently endure severe pain, which substantially diminishes their quality of life and can adversely impact survival. Analgesia, a critical modality for alleviating such pain, is now under scrutiny for its potential role in cancer progression, a relationship whose underlying mechanisms remain obscure. Emerging evidence suggests that lactate, once considered a metabolic byproduct, actively participates in the malignant progression of cancer by modulating both metabolic and immunological pathways within the tumor microenvironment. Furthermore, lactate is implicated in the modulation of cancer-related pain, exerting effects through direct and indirect mechanisms. This review synthesizes current understanding of lactate's production, transport, and functional roles in tumor cells, encompassing the regulation of tumor metabolism, immunity, and progression. Additionally, we dissect the complex, bidirectional relationship between lactate and pain, and assess the impact of anesthetics on pain relief, lactate homeostasis, and tumorigenesis.

The Role of Lactate and Lactylation in the Dysregulation of Immune Responses in Psoriasis

Historically, lactate has been considered merely a metabolic byproduct. However, recent studies have revealed that lactate plays a much more dynamic role, acting as an immune signaling molecule that influences cellular communication, through the process of "lactate shuttling." Lactylation, a novel post-translational modification, is directly derived from lactate and represents an emerging mechanism through which lactate exerts its effects on cellular function. It has been shown to directly affect immune cells by modulating the activation of pro-inflammatory and anti-inflammatory pathways. This modification influences the expression of key immune-related genes, thereby impacting immune cell differentiation, cytokine production, and overall immune response. In this review, we focused on the role of lactate and lactylation in the dysregulation of immune responses in psoriasis and its relapse. Additionally, we discuss the potential applications of targeting lactate metabolism and lactylation modifications in the treatment of psoriasis, alongside the investigation of artificial intelligence applications in advancing lactate and lactylation-focused drug development, identifying therapeutic targets, and enabling personalized medical decision-making. The significance of this review lies in its comprehensive exploration of how lactate and lactylation contribute to immune dysregulation, offering a novel perspective for understanding the metabolic and epigenetic changes associated with psoriasis. By identifying the roles of these pathways in modulating immune responses, this review provides a foundation for the development of new therapeutic strategies that target these mechanisms.

Lactylation: a promising therapeutic target in ischemia-reperfusion injury management

Ischemia-reperfusion injury (IRI) is a critical condition that poses a significant threat to patient safety. The production of lactate increases during the process of IRI, and lactate serves as a crucial indicator for assessing the severity of such injury. Lactylation, a newly discovered post-translational modification in 2019, is induced by lactic acid and predominantly occurs on lysine residues of histone or nonhistone proteins. Extensive studies have demonstrated the pivotal role of lactylation in the pathogenesis and progression of various diseases, including melanoma, myocardial infarction, hepatocellular carcinoma, Alzheimer's disease, and nonalcoholic fatty liver disease. Additionally, a marked correlation between lactylation and inflammation has been observed. This article provides a comprehensive review of the mechanism underlying lactylation in IRI to establish a theoretical foundation for better understanding the interplay between lactylation and IRI.

The role of lactate metabolism and lactylation in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a complex and progressive disease characterized by elevated pulmonary artery pressure and vascular remodeling. Recent studies have underscored the pivotal role of metabolic dysregulation and epigenetic modifications in the pathogenesis of PAH. Lactate, a byproduct of glycolysis, is now recognized as a key molecule that links cellular metabolism with activity regulation. Recent findings indicate that, in addition to altered glycolytic activity and dysregulated. Lactate homeostasis and lactylation-a novel epigenetic modification-also play a significant role in the development of PAH. This review synthesizes current knowledge regarding the relationship between altered glycolytic activity and PAH, with a particular focus on the cumulative effects of lactate in pulmonary vascular cells. Furthermore, lactylation, an emerging epigenetic modification, is discussed in the context of PAH. By elucidating the complex interplay between lactate metabolism and lactylation in PAH, this review aims to provide insights into potential therapeutic targets. Understanding these metabolic pathways may lead to innovative strategies for managing PAH and improving patient outcomes. Future research should focus on the underlying mechanisms through which lactylation influences the pathophysiology of PAH, thereby aiding in the development of targeted interventions.

L- and D-Lactate: unveiling their hidden functions in disease and health

Lactate, once considered a mere byproduct of anaerobic metabolism, is now recognized as a critical signaling molecule with diverse roles in physiology and pathology. There are two stereoisomers of lactate: L- and D-lactate. Recent studies have shown that disruptions in these two lactate stereoisomers have distinct effects on health and disease. L-lactate is central to glycolysis and energy transfer through the Cori cycle but also acts as the dominant lactylation isomer induced by glycolysis, influencing metabolism and cell survival. Although less studied, D-lactate is linked to metabolic disorders and plays a role in mitochondrial dysfunction and oxidative stress. This review focuses on both L- and D-lactate and examines their biosynthesis, transport, and expanding roles in physiological and pathological processes, particularly their functions in cancer, immune regulation, inflammation, neurodegeneration and other diseases. Finally, we assess the therapeutic prospects of targeting lactate metabolism, highlighting emerging strategies for intervention in clinical settings. Our review synthesizes the current understanding of L- and D-lactate, offering insights into their potential as targets for therapeutic innovation.