Hypoxia induced β-catenin lactylation promotes the cell proliferation and stemness of colorectal cancer through the wnt signaling pathway

H 2 protects H9c2 cells from hypoxia/reoxygenation injury by inhibiting the Wnt/CX3CR1 signaling pathway

Myocardial ischemia‒reperfusion injury is a severe cardiovascular disease, and its treatment and prevention are crucial for improving patient prognosis and reducing the economic burden. This study aimed to explore the impact of hydrogen (H 2 ) on hypoxia/reoxygenation (H/R) injury in H9c2 cells (derived from rat embryonic heart tissue) induced by hydrogen peroxide (H 2 O 2 ) and to elucidate its underlying mechanism. An H/R injury model was established in H9c2 cells via exposure to 15 μM H 2 O 2 for 3 hours, followed by incubation in a 5% CO 2 atmosphere at 37°C for 24 hours. Then, the cells were treated with H 2 (50%) for 6, 12 or 24 hours. The results demonstrated that H9c2 cells exposed to H 2 O 2 and subjected to H/R injury presented a marked decrease in the cell survival rate, accompanied by severe morphological alterations, such as curling and wrinkling, and elevated lactate dehydrogenase levels. Notably, H 2 mitigated H/R injury induced by H 2 O 2 in a time-dependent manner, improving the morphological damage observed in H9c2 cells and decreasing lactate dehydrogenase levels. Compared with the model group, treatment with H 2 increased the activities of antioxidant enzymes, including catalase, superoxide dismutase, and glutathione peroxidase, while concurrently reducing the level of malondialdehyde, an indicator of cellular damage. Furthermore, H 2 treatment downregulated the expression of inflammatory cytokines and inflammatory-related factors, specifically interleukin-6, high-mobility group box 1, tumor necrosis factor-alpha, and Toll-like receptor 4, in H9c2 cells post-H/R injury. Furthermore, H 2 treatment resulted in a marked decrease in the expression levels of proteins associated with the Wnt/C-X3-C-motif receptor 1 signaling pathway, such as β-catenin, glycogen synthase kinase-3 beta, adenomatous polyposis coli, and Wnt and C-X3-C-motif receptor 1. This observation suggests a potential mechanism for its protective effects against H/R injury. Therefore, H 2 exerts a protective effect against H/R injury in H9c2 cells induced by H 2 O 2 , potentially by inhibiting the activated Wnt/C-X3-C-motif receptor 1 signaling pathway. This inhibition, in turn, prevents the generation of oxidative stress, inflammatory cytokines, and inflammation-associated factors.

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.

Predictive role of lactylation-related gene signature in the prognosis and immunotherapy response in bladder cancer

OBJECTIVE

Lactylation is a type of chemical modification involving the introduction of lactyl groups to a molecule which can affect the interactions between tumor cells and their microenvironment. This study aims to evaluate the possible role of lactylation-related gene signature in the prediction of both prognosis and immunotherapy response in bladder cancer (BLCA).

METHODS

Lactylation-related genes were obtained from the published work and two subtypes (cluster A and B) were identified through unsupervised clustering. The differences including clinical features, differentially expressed genes (DEGs), pathways, and immune cell infiltration between these two clusters were thoroughly examined.

RESULTS

By utilizing the DEGs between the two clusters, a lactylation score was identified to predict the overall survival status and the response of BLCA patients receiving immunotherapy. Our results demonstrated that patients with a high lactylation score tended to have a worse survival period and increased immune cell infiltration level. Further analysis showed that high lactylation score may be associated with higher sensitivity to immune checkpoint inhibitor (ICI) treatment which is crucial in the identification of the suitable candidates for ICI therapy.

CONCLUSIONS

Our results emphasize the possible predictive role of lactylation-related gene signature both in the survival rates of BLCA and its implications for treatment strategies.

Protein lactylation in cancer: mechanisms and potential therapeutic implications

Increased glycolysis, which leads to high lactate production, is a common feature of cancer cells. Recent evidence suggests that lactate plays a role in the post-translational modification of histone and nonhistone proteins via lactylation. In contrast to genetic mutations, lactylation in cancer cells is reversible. Thus, reversing lactylation can be exploited as a pharmacological intervention for various cancers. Here we discuss recent advances in histone and nonhistone lactylation in cancer, including L-, D- and S-lactylation, as well as alanyl-tRNA synthetase as a novel lactyltransferase. We also discuss potential approaches for targeting lactylation as a therapeutic opportunity in cancer treatment.

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.

Regulatory role and therapeutic prospect of lactate modification in cancer

Post-translational modifications (PTMs) of proteins refer to the process of adding chemical groups, sugars, or other molecules to specific residues of target proteins following their biosynthesis by ribosomes. PTMs play a crucial role in processes such as signal transduction, epigenetics, and disease development. Lactylation is a newly discovered PTM that, due to its close association with lactate-the end product of glycolytic metabolism-provides a new perspective on the connection between cellular metabolic reprogramming and epigenetic regulation. Studies have demonstrated that lactylation plays a significant role in tumor progression and is associated with poor clinical prognosis. Abnormal histone lactylation can influence gene expression in both tumor cells and immune cells, thereby regulating tumor progression and immunosuppression. Lactylation of non-histone proteins can also modulate processes such as tumor proliferation and drug resistance. This review summarizes the latest research progress in the field of lactylation, highlighting its roles and mechanisms in tumorigenesis, tumor development, the tumor microenvironment, and immunosuppression. It also explores the potential application value of lactylation in tumor-targeted therapy and combined immunotherapy.

Deciphering Aflatoxin B1 affected critical molecular pathways governing cancer: A bioinformatics study using CTD and PANTHER databases

Aflatoxin B1 (AFB1) is a fungal toxin consistently found as a contaminant in food products such as cereals, nuts, spices, and oilseeds. AFB1 exposure can lead to hepatotoxicity, cancer, immune suppression, reproductive deficiency, nutritional dysfunction, and growth impairment. AFB1 has also been listed as one of the most potent human carcinogens by the International Agency for Research on Cancer. Although the correlation between AFB1 exposure and cancer initiation and progression is already reported in the literature, very little information is available about what molecular pathways are affected during cancer development. Considering this, we first selected AFB1-responsive genes involved in five deadliest cancer types including lung, colorectal, liver, stomach, and breast cancers from the Comparative Toxicogenomics Database (CTD). Then, using the PANTHER database, a statistical overrepresentation test was performed to identify the significantly affected pathways in each cancer type. The gonadotropin-releasing hormone receptor (GnRHR) pathway, the CCKR signaling pathway, and angiogenesis were found to be the most affected pathways in lung, breast, liver, and stomach cancers. In addition, AFB1 toxicity majorly impacted apoptosis and Wnt signaling pathways in liver and stomach cancers, respectively. Moreover, the most affected pathways in colorectal cancer were the Wnt, CCKR, and GnRHR pathways. Furthermore, gene analysis was also performed for the most affected pathways associated with each cancer and identified thirteen key genes (e.g., FOS, AKT1) that may serve as biological markers for a particular type of AFB1-induced cancer as well as for in vitro AFB1 toxicological studies using specific cancer cell lines.

Unlocking the multifaceted molecular functions and diverse disease implications of lactylation

In recent years, a significant breakthrough has emerged in biology, the identification of lactylation, a novel post-translational process. This intriguing modification is not limited to a specific class of proteins but occurs across a diverse range, including histones, signalling molecules, enzymes, and substrates. It can exert a broad regulatory role in various diseases, ranging from developmental anomalies and neurodegenerative disorders to inflammation and cancer. Thus, it presents exciting opportunities for exploring innovative treatment approaches. As a result, there has been a recent surge of research interest, leading to a deeper understanding of the molecular mechanisms and regulatory functions underlying lactylation within physiological and pathological processes. Here, we review the detection and molecular mechanisms of lactylation, from biological functions to disease effects, providing a systematic overview of the mechanisms and functions of this post-translational modification.

Lactylation: The metabolic accomplice shaping cancer's response to radiotherapy and immunotherapy

Protein lactylation, an emerging post-translational modification, is providing new insights into tumor biology and challenging our current understanding of cancer mechanisms. Our review illuminates the intricate roles of lactylation in carcinogenesis, tumor progression, and therapeutic responses, positioning it as a critical linchpin connecting metabolic reprogramming, epigenetic modulation, and treatment outcomes. We provide an in-depth analysis of lactylation's molecular mechanisms and its far-reaching impact on cell cycle regulation, immune evasion strategies, and therapeutic resistance within the complex tumor microenvironment. Notably, this review dissects the paradoxical nature of lactylation in cancer immunotherapy and radiotherapy. While heightened lactylation can foster immune suppression and radioresistance, strategically targeting lactylation cascades opens innovative avenues for amplifying the efficacy of current treatment paradigms. We critically evaluate lactylation's potential as a robust diagnostic and prognostic biomarker and explore frontier therapeutic approaches targeting lactylation. The synergistic integration of multi-omics data and artificial intelligence in lactylation research is catalyzing significant strides towards personalized cancer management. This review not only consolidates current knowledge but also charts a course for future investigations. Key research imperatives include deciphering tumor-specific lactylation signatures, optimizing synergistic strategies combining lactylation modulation with immune checkpoint inhibitors and radiotherapy, and comprehensively assessing the long-term physiological implications of lactylation intervention. As our understanding of lactylation's pivotal role in tumor biology continues to evolve, this burgeoning field promises to usher in transformative advancements in cancer diagnosis, treatment modalitie.

Lactate-induced protein lactylation in cancer: functions, biomarkers and immunotherapy strategies

Lactate, long viewed as a byproduct of glycolysis and metabolic waste. Initially identified within the context of yogurt fermentation, lactate's role extends beyond culinary applications to its significance in biochemical processes. Contemporary research reveals that lactate functions not merely as the terminal product of glycolysis but also as a nexus for initiating physiological and pathological responses within the body. Lysine lactylation (Kla), a novel post-translational modification (PTM) of proteins, has emerged as a pivotal mechanism by which lactate exerts its regulatory influence. This epigenetic modification has the potential to alter gene expression patterns, thereby impacting physiological and pathological processes. Increasing evidence indicates a correlation between lactylation and adverse prognosis in various malignancies. Consequently, this review article aims to encapsulate the proteins that interact with lactate, elucidate the role of lactylation in tumorigenesis and progression, and explore the potential therapeutic targets afforded by the modulation of lactylation. The objective of this review is to clarify the oncogenic significance of lactylation and to provide a strategic framework for future research directions in this burgeoning field.

Lactate and lactylation in gastrointestinal cancer: Current progress and perspectives (Review)

Gastrointestinal (GI) cancers, which have notable incidence and mortality, are impacted by metabolic reprogramming, especially the increased production and accumulation of lactate. Lactylation, a post‑translational modification driven by lactate, is a crucial regulator of gene expression and cellular function in GI cancer. The present review aimed to examine advancements in understanding lactate and lactylation in GI cancer. The mechanisms of lactate production, its influence on the tumor microenvironment and the clinical implications of lactate levels as potential biomarkers were explored. Furthermore, lactylation was investigated, including its biochemical foundation, primary targets and functional outcomes. The present review underscored potential therapeutic strategies targeting lactate metabolism and lactylation. Challenges and future directions emphasize the potential of lactate and lactylation as innovative therapeutic targets in GI cancer to improve clinical outcomes.

Hypoxia promotes non-small cell lung cancer cell stemness, migration, and invasion via promoting glycolysis by lactylation of SOX9

BACKGROUND

Lung cancer is the deadliest form of malignancy and the most common subtype is non-small cell lung cancer (NSCLC). Hypoxia is a typical feature of solid tumor microenvironment. In the current study, we clarified the effects of hypoxia on stemness and metastasis and the molecular mechanism.

METHODS

The biological functions were assessed using the sphere formation assay, Transwell assay, and XF96 extracellular flux analyzer. The protein levels were detected by western blot. The lactylation modification was assessed by western blot and immunoprecipitation. The role of SOX9 in vivo was explored using a xenografted tumor model.

RESULTS

We observed that hypoxia promoted sphere formation, migration, invasion, glucose consumption, lactate production, glycolysis, and global lactylation. Inhibition of glycolysis suppressed cell stemness, migration, invasion, and lactylation. Moreover, hypoxia increased the levels of SOX9 and lactylation of SOX9, whereas inhibition of glycolysis reversed the increase. Additionally, knockdown of SOX9 abrogated the promotion of cell stemness, migration, and invasion. In tumor-bearing mice, overexpression of SOX9 promoted tumor growth, and inhibition of glycolysis suppressed tumor growth.

CONCLUSION

Hypoxia induced the lactylation of SOX9 to promote stemness, migration, and invasion via promoting glycolysis. The findings suggested that targeting hypoxia may be an effective way for NSCLC treatment and reveal a new mechanism of hypoxia in NSCLC.

The molecular mechanisms of cardiac development and related diseases

Cardiac development is a complex and intricate process involving numerous molecular signals and pathways. Researchers have explored cardiac development through a long journey, starting with early studies observing morphological changes and progressing to the exploration of molecular mechanisms using various molecular biology methods. Currently, advancements in stem cell technology and sequencing technology, such as the generation of human pluripotent stem cells and cardiac organoids, multi-omics sequencing, and artificial intelligence (AI) technology, have enabled researchers to understand the molecular mechanisms of cardiac development better. Many molecular signals regulate cardiac development, including various growth and transcription factors and signaling pathways, such as WNT signaling, retinoic acid signaling, and Notch signaling pathways. In addition, cilia, the extracellular matrix, epigenetic modifications, and hypoxia conditions also play important roles in cardiac development. These factors play crucial roles at one or even multiple stages of cardiac development. Recent studies have also identified roles for autophagy, metabolic transition, and macrophages in cardiac development. Deficiencies or abnormal expression of these factors can lead to various types of cardiac development abnormalities. Nowadays, congenital heart disease (CHD) management requires lifelong care, primarily involving surgical and pharmacological treatments. Advances in surgical techniques and the development of clinical genetic testing have enabled earlier diagnosis and treatment of CHD. However, these technologies still have significant limitations. The development of new technologies, such as sequencing and AI technologies, will help us better understand the molecular mechanisms of cardiac development and promote earlier prevention and treatment of CHD in the future.

Highlighting function of Wnt signalling in urological cancers: Molecular interactions, therapeutic strategies, and (nano)strategies

Cancer is a complex, multistep process characterized by abnormal cell growth and metastasis as well as the capacity of the tumor cells in therapy resistance development. The urological system is particularly susceptible to a group of malignancies known as urological cancers, where an accumulation of genetic alterations drives carcinogenesis. In various human cancers, Wnt singalling is dysregulated; following nuclear transfer of β-catenin, it promotes tumor progression and affects genes expression. Elevated levels of Wnt have been documented in urological cancers, where its overexpression enhances growth and metastasis. Additionally, increased Wnt singalling contributes to chemoresistance in urological cancers, leading to reduced sensitivity to chemotherapy agents like cisplatin, doxorubicin, and paclitaxel. Wnt upregulation can change radiotherapy response of urological cancers. The regulation of Wnt involves various molecular pathways, including Akt, miRNAs, lncRNAs, and circRNAs, all of which play roles in carcinogenesis. Targeting and silencing Wnt or its associated pathways can mitigate tumorigenesis in urological cancers. Anti-cancer compounds such as curcumin and thymoquinone have shown efficacy in suppressing tumorigenesis through the downregulation of Wnt singalling. Notably, nanoparticles have proven effective in treating urological cancers, with several studies in prostate cancer (PCa) using nanoparticles to downregulate Wnt and suppress tumor growth. Future research should focus on developing small molecules that inhibit Wnt singalling to further suppress tumorigenesis and advance the treatment of urological cancers. Moreover, Wnt can be used as reliable biomarker for the diagnosis and prognosis of urological cancers.

Lactylation in cancer: Mechanisms in tumour biology and therapeutic potentials

Lactylation, a recently identified form of protein post-translational modification (PTM), has emerged as a key player in cancer biology. The Warburg effect, a hallmark of tumour metabolism, underscores the significance of lactylation in cancer progression. By regulating gene transcription and protein function, lactylation facilitates metabolic reprogramming, enabling tumours to adapt to nutrient limitations and sustain rapid growth. Over the past decade, extensive research has revealed the intricate regulatory network underlying lactylation in tumours. Large-scale sequencing and machine learning have confirmed the widespread occurrence of lactylation sites across the tumour proteome. Targeting lactylation enzymes or metabolic pathways has demonstrated promising anti-tumour effects, highlighting the therapeutic potential of this modification. This review comprehensively explores the mechanisms of lactylation in cancer cells and the tumour microenvironment. We expound on the application of advanced omics technologies for target identification and data modelling within the lactylation field. Additionally, we summarise existing anti-lactylation drugs and discuss their clinical implications. By providing a comprehensive overview of recent advancements, this review aims to stimulate innovative research and accelerate the translation of lactylation-based therapies into clinical practice. KEY POINTS: Lactylation significantly influences tumour metabolism and gene regulation, contributing to cancer progression. Advanced sequencing and machine learning reveal widespread lactylation sites in tumours. Targeting lactylation enzymes shows promise in enhancing anti-tumour drug efficacy and overcoming chemotherapy resistance. This review outlines the clinical implications and future research directions of lactylation in oncology.

Hypoxia-induced SHMT2 protein lactylation facilitates glycolysis and stemness of esophageal cancer cells

Esophageal cancer (EC) is a familiar digestive tract tumor with highly lethal. The hypoxic environment has been demonstrated to be a significant factor in modulating malignant tumor progression and is strongly associated with the abnormal energy metabolism of tumor cells. Serine hydroxymethyl transferase 2 (SHMT2) is one of the most frequently expressed metabolic enzymes in human malignancies. The study was designed to investigate the biological functions and regulation mechanisms of SHMT2 in EC under hypoxia. We conducted RT-qPCR to assess SHMT2 levels in EC tissues and cells (TE-1 and EC109). EC cells were incubated under normoxia and hypoxia, respectively, and altered SHMT2 expression was evaluated through RT-qPCR, western blot, and immunofluorescence. The biological functions of SHMT2 on EC cells were monitored by performing CCK-8, EdU, transwell, sphere formation, glucose uptake, and lactate production assays. The SHMT2 protein lactylation was measured by immunoprecipitation and western blot. In addition, SHMT2-interacting proteins were analyzed by bioinformatics and validated by rescue experiments. SHMT2 was notably upregulated in EC tissues and cells. Hypoxia elevated SHMT2 protein expression, augmenting EC cell proliferation, migration, invasion, stemness, and glycolysis. In addition, hypoxia triggered lactylation of the SHMT2 protein and enhanced its stability. SHMT2 knockdown impeded the malignant phenotype of EC cells. Further mechanistic studies disclosed that SHMT2 is involved in EC progression by interacting with MTHFD1L. Hypoxia-induced SHMT2 protein lactylation and upregulated its protein level, which in turn enhanced MTHFD1L expression and accelerated the malignant progression of EC cells.

Landscape of epithelial cell subpopulations in the human esophageal squamous cell carcinoma microenvironment

Aims

We sought to reveal the landscape of epithelial cell subpopulations in the human esophageal squamous cell carcinoma microenvironment and investigate their parts on esophageal squamous carcinoma (ESCC) development.

Background

Epithelial cells play an important role in the occurrence and development of ESCC through multiple mechanisms. While the landscape of epithelial cell subpopulations in ESCC, remains unclear.

Objective

Exploring the role of epithelial cell subpopulations in ESCC progression.

Methods

Seurat R package was used for single-cell RNA sequencing (scRNA-seq) data filtering, dimensionality reduction, clustering and differentially expressed genes analysis. Cellmarker database was adopted for cell cluster annotation. Functional enrichment analysis was carried out by Gene Ontology (GO) analysis. InferCNV package was conducted for copy number variation (CNV) of epithelial cell subpopulations in all chromosomal regions. Pseudotime trajectory analysis was implemented for exploring differentiation trajectory of epithelial cells subgroups during the cancer progression. CellChat analysis was used for probing the interactions between epithelial cells and NK/T cells. cellular experiments were performed using Quantitative Real-Time Polymerase Chain Reaction (RT-qPCR), Wound-Healing Assay and transwell.

Results

11 major cell subpopulations were identified in ESCC and adjunct tissues. Further reclassification of epithelial cells uncovered 4 subpopulations. Enrichment analysis revealed that highly expressed genes in 4 epithelial cell subpopulations were related to cell proliferation, immune response and angiogenesis. CNV analysis found that UBD + epithelial cells and GAS2L3+ epithelial cells had a higher proportion of CNV. Cell differentiation trajectories disclosed that KRT6C+ and GSTA1+ epithelial cells were in an intermediate state of differentiation, while UBD+ and GAS2L3+ epithelial cells are in an end state of differentiation during ESCC progression. Finally, we found that four epithelial cell subpopulations all inhibited NK/T cells through NECTIN2-TIGIT and CLEC2B-KLRB1. Low ATF3 and DDIT3 mRNA expression inhibited ESCC cell migration and invasion.

Conclusion

Here, we obtained a through epithelial cell atlas of ESCC at single-cell resolution, explored the role of epithelial cell in ESCC progression, and unveiled immunosuppressive signals to NK/T cells in promoting ESCC. Our findings expand the comprehension of epithelial cells and offer a theoretical guidance for future anti-epithelial cell treatment of ESCC.

The role of nonhistone lactylation in disease

In 2019, a novel post-translational modification termed lactylation was identified, which established a connection among lactate, transcriptional regulation and epigenetics. Lactate, which is traditionally viewed as a metabolic byproduct, is now recognized for its significant functional role, including modulating the tumor microenvironment, engaging in signaling and interfering in immune regulation. While research on lactylation (KLA) is advancing, the focus has primarily been on histone lactylation. This paper aims to explore the less-studied area of nonhistone lactylation, highlighting its involvement in certain diseases and physiological processes. Additionally, the clinical relevance and potential implications of nonhistone lactylation will be discussed.

Functional gene signature offers a powerful tool for characterizing clinicopathological features and depicting tumor immune microenvironment of colorectal cancer

BACKGROUND

Colorectal cancer, a prevalent malignancy worldwide, poses a significant challenge due to the lack of effective prognostic tools. In this study, we aimed to develop a functional gene signature to stratify colorectal cancer patients into different groups with distinct characteristics, which will greatly facilitate disease prediction.

RESULTS

Patients were stratified into high- and low-risk groups using a prediction model built based on the functional gene signature. This innovative approach not only predicts clinicopathological features but also reveals tumor immune microenvironment types and responses to immunotherapy. The study reveals that patients in the high-risk group exhibit poorer pathological features, including invasion depth, lymph node metastasis, and distant metastasis, as well as unfavorable survival outcomes in terms of overall survival and disease-free survival. The underlying mechanisms for these observations are attributed to upregulated tumor-related signaling pathways, increased infiltration of pro-tumor immune cells, decreased infiltration of anti-tumor immune cells, and a lower tumor mutation burden. Consequently, patients in the high-risk group exhibit a diminished response to immunotherapy. Furthermore, the high-risk group demonstrates enrichment in extracellular matrix-related functions and significant infiltration of cancer-associated fibroblasts (CAFs). Single-cell transcriptional data analysis identifies CAFs as the primary cellular type expressing hub genes, namely ACTA2, TPM2, MYL9, and TAGLN. This finding is further validated through multiple approaches, including multiplex immunohistochemistry (mIHC), polymerase chain reaction (PCR), and western blot analysis. Notably, TPM2 emerges as a potential biomarker for identifying CAFs in colorectal cancer, distinguishing them from both colorectal cancer cell lines and normal colon epithelial cell lines. Co-culture of CAFs and colorectal cancer cells revealed that CAFs could enhance the tumorigenic biofunctions of cancer cells indirectly, which could be partially inhibited by knocking down CAF original TPM2 expression.

CONCLUSIONS

This study introduces a functional gene signature that effectively and reliably predicts clinicopathological features and the tumor immune microenvironment in colorectal cancer. Moreover, the identification of TPM2 as a potential biomarker for CAFs holds promising implications for future research and clinical applications in the field of colorectal cancer.

Astragali Radix-Curcumae Rhizoma herb pair reduces the stemness of colorectal cancer cells through HIF-2α/β-catenin pathway

BACKGROUND

Colorectal cancer (CRC) is one of the most common causes of cancer-related mortality and significantly impairs quality of life. Astragali Radix-Curcumae Rhizoma (AC) is widely employed in the treatment of CRC in Chinese medicine, but the precise mechanisms remain unclear.

PURPOSE

This study aimed to elucidate the mechanisms by which AC inhibits CRC progression.

METHODS

The active components of AC were identified using UPLC-MS/MS analysis. An orthotopic transplantation colorectal tumor model was established in BALB/c mice using the CT26-Lucifer cell line to evaluate the effects of AC. Tumor volumes were monitored using IVIS imaging technology. Histological examination of tumor morphology was performed with hematoxylin and eosin (H&E) staining. Transcriptomic sequencing of mouse tumor samples was conducted to identify critical pathways and molecular targets. The impact of AC on cell viability and migration was assessed using CCK-8 and wound healing assays, respectively. To investigate the effects of AC on CRC cells, an in vitro hypoxic model was established using cobalt chloride (CoCl2), a hypoxia inducer. HIF-2α overexpression was achieved by constructing stable lentiviral vectors. Key targets identified from RNA-seq, such as c-Myc, Ki-67, β-catenin, cleaved caspase 3, CD133, and CD44, were evaluated using western blotting, qRT-PCR, and immunofluorescence assays. Epithelial-Mesenchymal Transition (EMT) and spheroid cloning assays were employed to evaluate phenotypic changes in cancer stem cells.

RESULTS

Twelve components of AC were identified. AC effectively inhibited CRC progression in vivo. Transcriptomic analysis highlighted hypoxic signaling as a significantly enriched pathway, implicating its role in suppressing CRC progression by AC. In the hypoxic model, AC inhibited the proliferation and migration of CRC cells in vitro. Furthermore, AC reduced cancer stemness by downregulating stemness markers, inhibiting EMT, and decreasing tumor sphere formation. The downregulation of hypoxic responses and the shift in stemness by AC involved attenuation of HIF-2α and WNT/β-catenin signaling.

CONCLUSION

This study provides the first evidence that AC reduces the stemness of CRC and the inhibition of the transition of CRC to stem-like cells by AC is closely related to the downregulation of the HIF-2α/β-catenin pathway, especially under hypoxic conditions.

Hypoxia exposure induces lactylation of Axin1 protein to promote glycolysis of esophageal carcinoma cells

The hypoxic microenvironment in esophageal carcinoma is an important factor promoting the rapid progression of malignant tumor. This study was to investigate the lactylation of Axin1 on glycolysis in esophageal carcinoma cells under hypoxia exposure. Hypoxia treatment increases pan lysine lactylation (pan-kla) levels of both TE1 and EC109 cells. Meanwhile, ECAR, glucose consumption and lactate production were also upregulated in both TE1 and EC109 cells. The expression of embryonic stem cell transcription factors NANOG and SOX2 were enhanced in the hypoxia-treated cells. Axin1 overexpression partly reverses the induction effects of hypoxia treatment in TE1 and EC109 cells. Moreover, lactylation of Axin1 protein at K147 induced by hypoxia treatment promotes ubiquitination modification of Axin1 protein to promote glycolysis and cell stemness of TE1 and EC109 cells. Mutant Axin1 can inhibit ECAR, glucose uptake, lactate secretion, and cell stemness in TE1 and EC109 cells under normal or hypoxia conditions. Meanwhile, mutant Axin1 further enhanced the effects of 2-DG on inhibiting glycolysis and cell stemness. Overexpression of Axin1 also inhibited tumor growth in vivo, and was related to suppressing glycolysis. In conclusion, hypoxia treatment promoted the glycolysis and cell stemness of esophageal carcinoma cells, and increased the lactylation of Axin1 protein. Overexpression of Axin1 functioned as a glycolysis inhibitor, and suppressed the effects of hypoxia exposure in vitro and inhibited tumor growth in vivo. Mechanically, hypoxia induces the lactylation of Axin1 protein and promotes the ubiquitination of Axin1 to degrade the protein, thereby exercising its anti-glycolytic function.

The relationship and clinical significance of lactylation modification in digestive system tumors

Lactylation, an emerging post-translational modification, plays a pivotal role in the initiation and progression of digestive system tumors. This study presents a comprehensive review of lactylation in digestive system tumors, underscoring its critical involvement in tumor development and progression. By focusing on metabolic reprogramming, modulation of the tumor microenvironment, and the molecular mechanisms regulating tumor progression, the potential of targeting lactylation as a therapeutic strategy is highlighted. The research reveals that lactylation participates in gene expression regulation and cell signaling by affecting the post-translational states of histones and non-histone proteins, thereby influencing metabolic pathways and immune evasion mechanisms in tumor cells. Furthermore, this study assesses the feasibility of lactylation as a therapeutic target, providing insights for clinical treatment of gastrointestinal cancers. Future research should concentrate on elucidating the mechanisms of lactylation, developing efficient lactylation inhibitors, and validating their therapeutic efficacy in clinical trials, which could transform current cancer treatment and immunotherapy approaches. In summary, this review emphasizes the crucial role of lactylation in tumorigenesis and progression through a detailed analysis of its molecular mechanisms and clinical significance.

Regulation of macrophage activation by lactylation in lung disease

Lactylation is a process where lactate, a cellular metabolism byproduct, is added to proteins, altering their functions. In the realm of macrophage activation, lactylation impacts inflammatory response and immune regulation. Understanding the effects of lactylation on macrophage activation is vital in lung diseases, as abnormal activation and function are pivotal in conditions like pneumonia, pulmonary fibrosis, COPD, and lung cancer. This review explores the concept of lactylation, its regulation of macrophage activation, and recent research progress in lung diseases. It offers new insights into lung disease pathogenesis and potential therapeutic targets.

Lactylation: The emerging frontier in post-translational modification

Lactate, a metabolic byproduct, has gained recognition as a highly influential signaling molecule. Lactylation, an emerging form of post-translational modification derived from lactate, plays a crucial role in numerous cellular processes such as inflammation, embryonic development, tumor proliferation, and metabolism. However, the precise molecular mechanisms through which lactylation governs these biological functions in both physiological and pathological contexts remain elusive. Hence, it is imperative to provide a comprehensive overview of lactylation in order to elucidate its significance in biological processes and establish a foundation for forthcoming investigations. This review aims to succinctly outline the process of lactylation modification and the characterization of protein lactylation across diverse organisms. Additionally, A summary of the regulatory mechanisms of lactylation in cellular processes and specific diseases is presented. Finally, this review concludes by delineating existing research gaps in lactylation and proposing primary directions for future investigations.

Dichloroacetate for Cancer Treatment: Some Facts and Many Doubts

Rarely has a chemical elicited as much controversy as dichloroacetate (DCA). DCA was initially considered a dangerous toxic industrial waste product, then a potential treatment for lactic acidosis. However, the main controversies started in 2008 when DCA was found to have anti-cancer effects on experimental animals. These publications showed contradictory results in vivo and in vitro such that a thorough consideration of this compound's in cancer is merited. Despite 50 years of experimentation, DCA's future in therapeutics is uncertain. Without adequate clinical trials and health authorities' approval, DCA has been introduced in off-label cancer treatments in alternative medicine clinics in Canada, Germany, and other European countries. The lack of well-planned clinical trials and its use by people without medical training has discouraged consideration by the scientific community. There are few thorough clinical studies of DCA, and many publications are individual case reports. Case reports of DCA's benefits against cancer have been increasing recently. Furthermore, it has been shown that DCA synergizes with conventional treatments and other repurposable drugs. Beyond the classic DCA target, pyruvate dehydrogenase kinase, new target molecules have also been recently discovered. These findings have renewed interest in DCA. This paper explores whether existing evidence justifies further research on DCA for cancer treatment and it explores the role DCA may play in it.

Wnt/β-catenin signalling, epithelial-mesenchymal transition and crosslink signalling in colorectal cancer cells

Colorectal cancer (CRC), with its significant incidence and metastatic rates, profoundly affects human health. A common oncogenic event in CRC is the aberrant activation of the Wnt/β-catenin signalling pathway, which drives both the initiation and progression of the disease. Persistent Wnt/β-catenin signalling facilitates the epithelial-mesenchymal transition (EMT), which accelerates CRC invasion and metastasis. This review provides a summary of recent molecular studies on the role of the Wnt/β-catenin signalling axis in regulating EMT in CRC cells, which triggers metastatic pathogenesis. We present a comprehensive examination of the EMT process and its transcriptional controllers, with an emphasis on the crucial functions of β-catenin, EMT transcription factors (EMT-TFs). We also review recent evidences showing that hyperactive Wnt/β-catenin signalling triggers EMT and metastatic phenotypes in CRC via "Destruction complex" of β-catenin mechanisms. Potential therapeutic and challenges approache to suppress EMT and prevent CRC cells metastasis by targeting Wnt/β-catenin signalling are also discussed. These include direct β-catenin inhibitors and novel targets of the Wnt pathway, and finally highlight novel potential combinational treatment options based on the inhibition of the Wnt pathway.

The crosstalk between glucose metabolism and telomerase regulation in cancer

Accumulated alterations in metabolic control provide energy and anabolic demands for enhanced cancer cell proliferation. Exemplified by the Warburg effect, changes in glucose metabolism during cancer progression are widely recognized as a characteristic of metabolic disorders. Since telomerases are a vital factor in maintaining DNA integrity and stability, any damage threatening telomerases could have a severe impact on DNA and, subsequently, whole-cell homeostasis. However, it remains unclear whether the regulation of glucose metabolism in cancer is connected to the regulation of telomerase. In this review, we present the latest insights into the crosstalk between telomerase function and glucose metabolism in cancer cells. However, at this moment this subject is not well investigated that the association is mostly indirectly regulations and few explicit regulating pathways were identified between telomerase and glucose metabolism. Therefore, the information presented in this review can provide a scientific basis for further research on the detail mechanism and the clinical application of cancer therapy, which could be valuable in improving the effectiveness of chemotherapy.

Integrated single-cell and bulk RNA-sequencing data reveal molecular subtypes based on lactylation-related genes and prognosis and therapeutic response in glioma

Objectives

Glioma, the most common and aggressive form of brain cancer, possesses a complex biology, which makes elucidating its underlying mechanisms and developing effective treatment strategies challenging. Lactylation is a recently discovered post-translational modification and has emerged as a novel research target to understand its role in various biological processes and diseases. Herein, we explored the role of lactylation in gliomas.

Methods

Single-cell RNA-sequencing (scRNA-seq) data were downloaded from the Tumour Immune Single-Cell Hub database. The R package 'Seurat' was used for processing the scRNA-seq data. Lactylation-related genes were identified from published literature and the Molecular Signatures Database. An unsupervised clustering method was used to identify glioma subtypes based on identified lactylation-related genes. Differences among the various clusters were examined, including clinical features, differentially expressed genes (DEGs), enriched pathways and immune cell infiltrates. A lactylation score was generated to predict the overall survival (OS) of patients with glioma using DEGs between the two clusters.

Results

The lactylation-related genes were obtained from the scRNA-seq data, identifying two molecular subtypes, and a prognostic signature was established to stratify patients with glioma into high- and low-score groups. Analysis of the tumour immune microenvironment revealed that patients in the high-score group exhibited increased immune cell infiltration, chemokine expression and immune checkpoint expression but exhibited worse OS and better response to immunotherapy.

Conclusions

Altogether, we established a novel signature based on lactylation-related clusters for robust survival prediction and immunotherapeutic response in gliomas.

Pathophysiological Implications of Protein Lactylation in Pancreatic Epithelial Tumors

Protein lactylation is a post-translational modification associated with glycolysis. Although recent evidence indicates that protein lactylation is involved in epigenetic gene regulation, its pathophysiological significance remains unclear, particularly in neoplasms. Herein, we investigated the potential involvement of protein lactylation in the molecular mechanisms underlying benign and malignant pancreatic epithelial tumors, as well as its role in the response of pancreatic cancer (PC) cells to gemcitabine. Increased lactylation was observed in the nuclei of intraductal papillary mucinous adenoma, non-invasive intraductal papillary mucinous carcinoma, and invasive carcinoma, in parallel to the upregulation of hypoxia-inducible factor-1α. This observation indicated that a hypoxia-associated increase in nuclear protein lactylation could be a biochemical hallmark in pancreatic epithelial tumors. The standard PC chemotherapy drug gemcitabine suppressed histone lactylation in vitro, suggesting that histone lactylation might be relevant to its mechanism of action. Taken together, our findings suggest that protein lactylation may be involved in the development of pancreatic epithelial tumors and could represent a potential therapeutic target for PC.

Regulation of newly identified lysine lactylation in cancer

Metabolic reprogramming is a typical hallmark of cancer. Enhanced glycolysis in tumor cells leads to the accumulation of lactate, which is traditionally considered metabolic waste. With the development of high-resolution liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), the lactate-derived, lysine lactylation(Kla), has been identified. Kla can alter the spatial configuration of chromatin and regulate the expression of corresponding genes. Metabolic reprogramming and epigenetic remodeling have been extensively linked. Accumulating studies have subsequently expanded the framework on the key roles of this protein translational modification (PTM) in tumors and have provided a new concept of cancer-specific regulation by Kla.

MUC20 regulated by extrachromosomal circular DNA attenuates proteasome inhibitor resistance of multiple myeloma by modulating cuproptosis

BACKGROUND

Proteasome inhibitors (PIs) are one of the most important classes of drugs for the treatment of multiple myeloma (MM). However, almost all patients with MM develop PI resistance, resulting in therapeutic failure. Therefore, the mechanisms underlying PI resistance in MM require further investigation.

METHODS

We used several MM cell lines to establish PI-resistant MM cell lines. We performed RNA microarray and EccDNA-seq in MM cell lines and collected human primary MM samples to explore gene profiles. We evaluated the effect of MUC20 on cuproptosis of PI-resistant MM cells using Co-immunoprecipitation (Co-IP), Seahorse bioenergetic profiling and in vivo assay.

RESULTS

This study revealed that the downregulation of Mucin 20 (MUC20) could predict PI sensitivity and outcomes in MM patients. Besides, MUC20 attenuated PI resistance in MM cells by inducing cuproptosis via the inhibition of cyclin-dependent kinase inhibitor 2 A expression (CDKN2A), which was achieved by hindering MET proto-oncogene, receptor tyrosine kinase (MET) activation. Moreover, MUC20 suppressed MET activation by repressing insulin-like growth factor receptor-1 (IGF-1R) lactylation in PI-resistant MM cells. This study is the first to perform extrachromosomal circular DNA (eccDNA) sequencing for MM, and it revealed that eccDNA induced PI resistance by amplifying kinesin family member 3 C (KIF3C) to reduce MUC20 expression in MM.

CONCLUSION

Our findings indicated that MUC20 regulated by eccDNA alleviates PI resistance of MM by modulating cuproptosis, which would provide novel strategies for the treatment of PI-resistant MM.

Histone lactylation bridges metabolic reprogramming and epigenetic rewiring in driving carcinogenesis: Oncometabolite fuels oncogenic transcription

Heightened lactate production in cancer cells has been linked to various cellular mechanisms such as angiogenesis, hypoxia, macrophage polarisation and T-cell dysfunction. The lactate-induced lactylation of histone lysine residues is noteworthy, as it functions as an epigenetic modification that directly augments gene transcription from chromatin. This epigenetic modification originating from lactate effectively fosters a reliance on transcription, thereby expediting tumour progression and development. Herein, this review explores the correlation between histone lactylation and cancer characteristics, revealing histone lactylation as an innovative epigenetic process that enhances the vulnerability of cells to malignancy. Moreover, it is imperative to acknowledge the paramount importance of acknowledging innovative therapeutic methodologies for proficiently managing cancer by precisely targeting lactate signalling. This comprehensive review illuminates a crucial yet inadequately investigated aspect of histone lactylation, providing valuable insights into its clinical ramifications and prospective therapeutic interventions centred on lactylation.

Ubiquitous protein lactylation in health and diseases

For decades, lactate has been considered a byproduct of glycolysis. The lactate shuttle hypothesis shifted the lactate paradigm, demonstrating that lactate not only plays important roles in cellular metabolism but also cellular communications, which can transcend compartment barriers and can occur within and among different cells, tissues and organs. Recently, the discovery that lactate can induce a novel post-translational modification, named lysine lactylation (Kla), brings forth a new avenue to study nonmetabolic functions for lactate, which has inspired a 'gold rush' of academic and commercial interest. Zhang et al. first showed that Kla is manifested in histones as epigenetic marks, and then mounting evidences demonstrated that Kla also occurs in diverse non-histone proteins. The widespread Kla faithfully orchestrates numerous biological processes, such as transcription, metabolism and inflammatory responses. Notably, dysregulation of Kla touches a myriad of pathological processes. In this review, we comprehensively reviewed and curated the existing literature to retrieve the new identified Kla sites on both histones and non-histone proteins and summarized recent major advances toward its regulatory mechanism. We also thoroughly investigated the function and underlying signaling pathway of Kla and comprehensively summarize how Kla regulates various biological processes in normal physiological states. In addition, we also further highlight the effects of Kla in the development of human diseases including inflammation response, tumorigenesis, cardiovascular and nervous system diseases and other complex diseases, which might potentially contribute to deeply understanding and interpreting the mechanism of its pathogenicity.

Scopolamine regulates the osteogenic differentiation of human periodontal ligament stem cells through lactylation modification of RUNX2 protein

Periodontal ligament stem cells (PDLSCs) are important mesenchymal stem cells contributing to regenerating lost periodontal tissues and repairing bone defects. Studies on the molecular mechanism affecting the osteogenic differentiation of PDLSCs are necessary. Scopolamine (SCO) is known as a regulator of neural cell damage. The focus of the current study is on unveiling the role of SCO-mediated molecular mechanism in the osteogenic differentiation of PDLSCs. Through CCK-8 assay and LDH detection, we confirmed that SCO enhanced the viability of PDLSCs. Moreover, we determined that SCO induced the PDLSCs osteogenic differentiation, according to data of ALP activity measurement and ARS staining. Mechanistically, we performed western blot and identified that SCO could promote the lactylation of runt-related transcription factor 2 (RUNX2). We also found through rescue assays that knockdown of RUNX2 could reverse the effect of SCO treatment on the osteogenic differentiation of PDLSCs. Further mechanism investigation revealed that lactylation of RUNX2 at K176 site enhances the protein stability of RUNX2 through deubiquitination. Collectively, our present study unveils that SCO stabilizes RUNX2 to promote the osteogenic differentiation of PDLSCs through the lactylation modification of RUNX2.

Post-translational protein lactylation modification in health and diseases: a double-edged sword

As more is learned about lactate, it acts as both a product and a substrate and functions as a shuttle system between different cell populations to provide the energy for sustaining tumor growth and proliferation. Recent discoveries of protein lactylation modification mediated by lactate play an increasingly significant role in human health (e.g., neural and osteogenic differentiation and maturation) and diseases (e.g., tumors, fibrosis and inflammation, etc.). These views are critically significant and first described in detail in this review. Hence, here, we focused on a new target, protein lactylation, which may be a "double-edged sword" of human health and diseases. The main purpose of this review was to describe how protein lactylation acts in multiple physiological and pathological processes and their potential mechanisms through an in-depth summary of preclinical in vitro and in vivo studies. Our work aims to provide new ideas for treating different diseases and accelerate translation from bench to bedside.

Functional Roles of CD133: More than Stemness Associated Factor Regulated by the Microenvironment

CD133 protein has been one of the most used surface markers to select and identify cancer cells with stem-like features. However, its expression is not restricted to tumoral cells; it is also expressed in differentiated cells and stem/progenitor cells in various normal tissues. CD133 participates in several cellular processes, in part orchestrating signal transduction of essential pathways that frequently are dysregulated in cancer, such as PI3K/Akt signaling and the Wnt/β-catenin pathway. CD133 expression correlates with enhanced cell self-renewal, migration, invasion, and survival under stress conditions in cancer. Aside from the intrinsic cell mechanisms that regulate CD133 expression in each cellular type, extrinsic factors from the surrounding niche can also impact CD33 levels. The enhanced CD133 expression in cells can confer adaptive advantages by amplifying the activation of a specific signaling pathway in a context-dependent manner. In this review, we do not only describe the CD133 physiological functions known so far, but importantly, we analyze how the microenvironment changes impact the regulation of CD133 functions emphasizing its value as a marker of cell adaptability beyond a cancer-stem cell marker.

Predicted Role of Acetyl-CoA Synthetase and HAT p300 in Extracellular Lactate Mediated Lactylation in the Tumor: In vitro and In silico Models

Background:

As per the Warburg effect, cancer cells are known to convert pyruvate into lactate. The accumulation of lactate is associated with metabolic and epigenetic reprogramming, which has newly been suggested to involve lactylation. However, the role of secreted lactate in modulating the tumor microenvironment through lactylation remains unclear. Specifically, there are gaps in our understanding of the enzyme responsible for converting lactate to lactyl-CoA and the nature of the enzyme that performs lactylation by utilizing lactyl-CoA as a substrate. It is worth noting that there are limited papers focused on metabolite profiling that detect lactate and lactyl-CoA levels intracellularly and extracellularly in the context of cancer cells.

Methods:

Here, we have employed an in-house developed vertical tube gel electrophoresis (VTGE) and LC-HRMS assisted profiling of extracellular metabolites of breast cancer cells treated by anticancer compositions of cow urine DMSO fraction (CUDF) that was reported previously. Furthermore, we used molecular docking and molecular dynamics (MD) simulations to determine the potential enzyme that can convert lactate to lactyl-CoA. Next, the histone acetyltransferase p300 (HAT p300) enzyme (PDB ID: 6GYR) was evaluated as a potential enzyme that can bind to lactylCoA during the lactylation process.

Results:

We collected evidence on the secretion of lactate in the extracellular conditioned medium of breast cancer cells treated by anticancer compositions. MD simulations data projected that acetyl-CoA synthetase could be a potential enzyme that may convert lactate into lactyl-CoA similar to a known substrate acetate. Furthermore, a specific and efficient binding (docking energy -9.6 kcal/mol) of lactyl-CoA with p300 HAT suggested that lactyl-CoA may serve as a substrate for lactylation similar to acetylation that uses acetyl-CoA as a substrate.

Conclusion:

In conclusion, our data provide a hint on the missing link for the lactylation process due to lactate in terms of a potential enzyme that can convert lactate into lactyl-CoA. This study helped us to project the HAT p300 enzyme that may use lactyl-CoA as a substrate in the lactylation process of the tumor microenvironment.

The role of lactate in cardiovascular diseases

Cardiovascular diseases pose a major threat worldwide. Common cardiovascular diseases include acute myocardial infarction (AMI), heart failure, atrial fibrillation (AF) and atherosclerosis. Glycolysis process often has changed during these cardiovascular diseases. Lactate, the end-product of glycolysis, has been overlooked in the past but has gradually been identified to play major biological functions in recent years. Similarly, the role of lactate in cardiovascular disease is gradually being recognized. Targeting lactate production, regulating lactate transport, and modulating circulating lactate levels may serve as potential strategies for the treatment of cardiovascular diseases in the future. The purpose of this review is to integrate relevant clinical and basic research on the role of lactate in the pathophysiological process of cardiovascular disease in recent years to clarify the important role of lactate in cardiovascular disease and to guide further studies exploring the role of lactate in cardiovascular and other diseases. Video Abstract.

Histone lactylation regulates cancer progression by reshaping the tumor microenvironment

As a major product of glycolysis and a vital signaling molecule, many studies have reported the key role of lactate in tumor progression and cell fate determination. Lactylation is a newly discovered post-translational modification induced by lactate. On the one hand, lactylation introduced a new era of lactate metabolism in the tumor microenvironment (TME), and on the other hand, it provided a key breakthrough point for elucidation of the interaction between tumor metabolic reprogramming and epigenetic modification. Studies have shown that the lactylation of tumor cells, tumor stem cells and tumor-infiltrating immune cells in TME can participate in the development of cancer through downstream transcriptional regulation, and is a potential and promising tumor treatment target. This review summarized the discovery and effects of lactylation, as well as recent research on histone lactylation regulating cancer progression through reshaping TME. We also focused on new strategies to enhance anti-tumor effects via targeting lactylation. Finally, we discussed the limitations of existing studies and proposed new perspectives for future research in order to further explore lactylation targets. It may provide a new way and direction to improve tumor prognosis.

Epigenetic modification of m6A regulator proteins in cancer

Divergent N6-methyladenosine (m6A) modifications are dynamic and reversible posttranscriptional RNA modifications that are mediated by m6A regulators or m6A RNA methylation regulators, i.e., methyltransferases ("writers"), demethylases ("erasers"), and m6A-binding proteins ("readers"). Aberrant m6A modifications are associated with cancer occurrence, development, progression, and prognosis. Numerous studies have established that aberrant m6A regulators function as either tumor suppressors or oncogenes in multiple tumor types. However, the functions and mechanisms of m6A regulators in cancer remain largely elusive and should be explored. Emerging studies suggest that m6A regulators can be modulated by epigenetic modifications, namely, ubiquitination, SUMOylation, acetylation, methylation, phosphorylation, O-GlcNAcylation, ISGylation, and lactylation or via noncoding RNA action, in cancer. This review summarizes the current roles of m6A regulators in cancer. The roles and mechanisms for epigenetic modification of m6A regulators in cancer genesis are segregated. The review will improve the understanding of the epigenetic regulatory mechanisms of m6A regulators.

Protein Posttranslational Modification in Stemness Remodeling and Its Emerging Role as a Novel Therapeutic Target in Gastrointestinal Cancers

The posttranslational modifications (PTMs) of proteins, as critical mechanisms for protein regulation, are well known to enhance the functional diversity of the proteome and dramatically participate in complicated biological processes. Recent efforts in the field of cancer biology have illustrated the extensive landscape of PTMs and their crosstalk with a wide range of pro-tumorigenic signaling pathways that decisively contribute to neoplastic transformation, tumor recurrence, and resistance to oncotherapy. Cancer stemness is an emerging concept that maintains the ability of tumor cells to self-renew and differentiate and has been recognized as the root of cancer development and therapy resistance. In recent years, the PTM profile for modulating the stemness of various tumor types has been identified. This breakthrough has shed light on the underlying mechanisms by which protein PTMs maintain cancer stemness, initiate tumor relapse, and confer resistance to oncotherapies. This review focuses on the latest knowledge of protein PTMs in reprogramming the stemness of gastrointestinal (GI) cancer. A deeper understanding of abnormal PTMs in specific proteins or signaling pathways provides an opportunity to specifically target cancer stem cells and highlights the clinical relevance of PTMs as potential biomarkers and therapeutic targets for patients with GI malignancies.