PCSK9 promotes the progression and metastasis of colon cancer cells through regulation of EMT and PI3K/AKT signaling in tumor cells and phenotypic polarization of macrophages

Fusobacterium nucleatum-derived 3-indolepropionic acid promotes colorectal cancer progression via aryl hydrocarbon receptor activation in macrophages

An increasing body of research indicates that Fusobacterium nucleatum (F. nucleatum) significantly influences the onset and progression of colorectal cancer (CRC). Our previous study has shown that F. nucleatum exerts pro-tumorigenic effects through aryl hydrocarbon receptor (AhR) activation. However, the role of its microbial metabolites in regulating immune responses remains unclear. Here, we report for the first time that F. nucleatum-derived 3-Indolepropionic acid (IPA) activates AhR in macrophages, driving M2 polarization and tumor-promoting immunosuppression. We discovered that culture supernatant of F. nucleatum (CSF) robustly activates AhR in macrophages. In co-culture systems, CSF upregulated the expression of the M2 marker CD206 and elevated mRNA levels of CD163, TGF-β, IL-10, and VEGF. In a subcutaneous allograft model, CSF induced an elevated number of CD206+ macrophages and decreased presence of CD8+ T cells within the tumor microenvironment, thereby promoting tumor growth. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed IPA as a novel major AhR-activating metabolite in CSF. Strikingly, IPA recapitulated CSF's effects in promoting tumor cell migration and immunosuppression, both in vitro and in vivo. Critically, the AhR inhibitor CH223191 abolished both IPA-mediated M2 polarization and tumor growth. Our study revealed a novel mechanism by which F. nucleatum-derived IPA reprograms macrophages through AhR activation to fuel CRC progression, providing potential therapeutic targets for CRC treatment and prognosis improvement.

M2 Macrophages Mitigate Ocular Surface Inflammation and Promote Recovery in a Mouse Model of Dry Eye

PURPOSE

Dry eye disease (DED) is a chronic, progressive, multifactorial condition characterized by tear film instability and ocular surface damage. Ocular surface inflammation is one of the main mechanisms of DED. This study aims to investigate the therapeutic effects of anti-inflammatory M2 macrophages on ocular surface inflammation and their potential mechanisms in improving dry eye symptoms in a mouse model.

METHODS

Mouse macrophages (RAW264.7) were polarized into M2 macrophages by IL-4 under different osmolarities, and M2 macrophage conditioned medium (M2-CM) was collected. Flow cytometry and ELISA were applied to measure the cytokine expression of the M2 macrophages. Primary mouse corneal epithelial cells (CECs) were co-cultured with RAW264.7 and M2 macrophages using a Transwell system. The viability and migration of CECs were assessed using CCK-8 and scratch assays. Mouse DED was established by subcutaneous injection of scopolamine, and the therapeutic effects of M2-CM were evaluated by phenol red thread test, fluorescein staining, and tear film breakup time (BUT). PCR and immunofluorescence staining were applied to observe inflammatory factors and cells on the ocular surface.

RESULTS

M2 macrophages enhanced CEC viability, proliferation, and migration, but hyperosmolarity inhibited M2 macrophage polarization. In the DED model, M2-CM improved ocular surface conditions, reduced pro-inflammatory cytokine expression, and increased anti-inflammatory factors. Immunofluorescence revealed reduced pro-inflammatory cells (M1 macrophages, Th1, and Th17) and increased M2 macrophages in the ocular tissues after M2-CM treatment.

CONCLUSION

These results suggest that M2-CM ameliorates ocular surface inflammation and promotes recovery in DED, offering a potential therapeutic strategy for DED.

Inclisiran in Cardiovascular Health: A Review of Mechanisms, Efficacy, and Future Prospects

Dyslipidemia is a significant risk factor for cardiovascular disease, and managing low-density lipoprotein cholesterol levels is a crucial strategy for both the prevention and treatment of cardiovascular disease. The active ingredient in the novel lipid-lowering drug, inclisiran, is a new type of small interfering RNA that primarily regulates blood lipid levels by inhibiting the synthesis of proprotein convertase subtilisin type 9 (PCSK9). Enhanced lipid-lowering effects can be achieved following 3 administrations. This article summarizes inclisiran's mechanism of action, efficacy, safety, current research hotspots, clinical applications, and future development prospects, based on the latest literature and research advancements. Through comparative analysis with traditional lipid-lowering drugs, we conclude that inclisiran has promising application prospects and market potential, as it can complement traditional statin therapies to enhance lipid-lowering efficiency. This not only provides convenience to patients but also improves treatment compliance. Its safety profile alleviates patients' concerns and mitigates the impact of negative emotions on their condition. Additionally, the potential applications of inclisiran in oncology have been identified. However, inclisiran also presents certain limitations and challenges. For instance, its long-term safety and efficacy require further investigation in future studies, and its high cost can restrict its widespread adoption and promotion. Furthermore, additional clinical evidence is needed to evaluate its synergistic or antagonistic effects when used in conjunction with other medications.

Tumor-Derived Exosomal circ_0020095 Promotes Colon Cancer Cell Proliferation and Metastasis by Inhibiting M1 Macrophage Polarization

Tumor-associated macrophages (TAM) have been shown to regulate colon cancer (CC) progression. However, it is not clear whether tumor-derived exosomal circular RNA (circRNA) regulates TAM to influence CC progression. The expression levels of circ_0020095, M1 macrophage markers, M2 macrophage markers, and interleukin-1 receptor-associated kinase 1 (IRAK1) were determined by qRT-PCR. Cell proliferation, migration and invasion were examined by EdU assay, wound healing assay and transwell assay. Exosomes derived from CC cells were used to treat M0 macrophages. M1 macrophage surface marker CD86 was detected by flow cytometry, and protein expression was examined by western blot. Then, the medium of exosome-treated M0 macrophages was used to culture CC cells to determine CC cell functions. RNA pull-down assay, RIP assay and dual-luciferase reporter assay were performed to validate interaction. Circ_0020095 had elevated expression in CC tissues and cells, and its knockdown repressed CC cell proliferation and metastasis. M0 macrophages could take by CC cell-derived exosomes to regulate circ_0020095 expression. Exosomal circ_0020095 restrained M1 macrophage polarization and increased M2 macrophage polarization to enhance CC cell progression. Besides, IRAK1 silencing could promote CC cell proliferation and metastasis by inhibiting M1 macrophage polarization, and its overexpression also abolished the effect of exosomal circ_0020095. Mechanistically, circ_0020095 could competitively bind to IGF2BP1 and then reduced the binding ability of IGF2BP1 and IRAK1 3'UTR. Tumor-derived exosomal circ_0020095 promoted CC cell progression via inhibiting M1 macrophage polarization through IGF2BP1/IRAK1 axis.

The Role of Cholesterol Metabolism and Its Regulation in Tumor Development

BACKGROUND

Within the tumor microenvironment, tumor cells undergo metabolic reprogramming of cholesterol due to intrinsic cellular alterations and changes in the extracellular milieu. Furthermore, cholesterol reprogramming within this microenvironment influences the immune landscape of tumors, facilitating immune evasion and consequently promoting tumorigenesis. These biological changes involve modifications in numerous enzymes associated with cholesterol uptake and synthesis, including NPC1L1, SREBP, HMGCR, SQLE, and PCSK9.

REVIEW

This review systematically summarizes the role of cholesterol metabolism and its associated enzymes in cancer progression, examines the mechanisms through which dysregulation of cholesterol metabolism affects immune cells within the tumor microenvironment, and discusses recent advancements in cancer therapies that target cholesterol metabolism.

CONCLUSION

Targeting cholesterol metabolism-related enzymes can inhibit tumor growth, reshape immune landscapes, and rejuvenate antitumor immunity, offering potential therapeutic avenues in cancer treatment.

Exploring the Pleiotropy of PCSK9: A Wide Range of Influences from Lipid Regulation to Extrahepatic Function

In cardiovascular disease, the discovery of the proprotein convertase subtilisin/kexin type 9 (PCSK9) has undoubtedly opened a new chapter in regulating blood lipids. Since its first identification as a key regulator of low-density lipoprotein receptor (LDLR) degradation in 2003, the role of PCSK9 in cholesterol metabolism has been extensively studied. However, with further research, the pleiotropy of PCSK9 has gradually emerged, and its impact extends far beyond cholesterol metabolism in the liver. The purpose of this review is to systematically explore the pleiotropy of PCSK9, extending from its important role in lipid regulation to its extensive effects in extrahepatic tissues, and to reveal its potential role in cardiovascular health, nervous system function, and tumor biology. By integrating the latest research findings, this paper summarizes the complex mechanisms of action of PCSK9 in different biological processes and explores its potential and challenges as a therapeutic target.

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.

PCSK9 Manipulates Lipid Metabolism and the Immune Microenvironment in Cancer

Cancer remains the foremost cause of mortality on a global scale. Immunotherapy has yielded remarkable outcomes in the fight against cancer and is regarded as one of the most crucial and promising therapeutic modalities. PCSK9, a critical target for plasma lipids control, has been extensively and deeply studied in multiple diseases. Currently, the functions of PCSK9 in cancer, particularly its immunomodulatory role, have been progressively revealed. PCSK9 is capable of modulating a variety of immune response throughout tumor progression by orchestrating lipid metabolism. Moreover, PCSK9 governs the cell fate of diverse immune cells, such as inflammatory factor signals, MHC signals, and TCR signals. This review comprehensively summarizes the current state of knowledge regarding the role and underlying mechanisms of PCSK9 in tumorigenesis, progression, immune escape, and drug resistance.

Methionine Metabolism Dictates PCSK9 Expression and Antitumor Potency of PD-1 Blockade in MSS Colorectal Cancer

Nutrient metabolisms are vitally interrelated to cancer progression and immunotherapy. However, the mechanisms by which nutrient metabolisms interact to remodel immune surveillance within the tumor microenvironment remain largely unexplored. Here it is demonstrated that methionine restriction inhibits the expression of proprotein convertase subtilisin/kexin type 9 (PCSK9), a key regulator of cholesterol homeostasis and a potential target for cancer immunotherapy, in colorectal cancer (CRC) but not in the liver. Mechanistically, methionine is catabolized to S-adenosylmethionine (SAM), promoting mRNA transcription of PCSK9 through increased DNA methyltransferase 1 (DNMT1)-mediated DNA methylation and suppression of sirtuin 6 (SIRT6) expression. Furthermore, both PCSK9 inhibition and dietary methionine restriction (DMR) potentiate PD-1 blockade therapy and foster the infiltration of CD8+ T cells in Colon 26 tumor-bearing mice-a proficient mismatch repair (pMMR)/microsatellite stable (MSS) CRC model that exhibits limited response to anti-PD-1 therapy. Moreover, combining 5-fluorouracil (5-FU) chemotherapy with PCSK9 inhibition and PD-1 blockade further augments therapeutic efficacy for MSS CRC. The findings establish a mechanistic link between amino acid metabolism and cholesterol metabolism within the tumor microenvironment where tumor cells sense methionine to regulate PCSK9 expression, highlighting promising combination therapeutic strategies that may greatly benefit MSS CRC patients.

Ezetimibe mediated RPS6KA2 inhibits colorectal cancer proliferation via PCSK9/MAPK signaling pathway

To investigate the effect and molecular mechanism of ezetimibe on colorectal cancer (CRC), our study found that ezetimibe significantly inhibited the proliferation and progression of CRC. Further study showed that RPS6KA2 might be the target gene of ezetimibe treatment on CRC. RPS6KA2 expression was significantly lower in human CRC tissue samples and associated with T classification and vascular invasion of tumor cells. RPS6KA2 inhibited proliferation, migration, and invasion of CRC cells. The underlying mechanisms indicated that interaction between RPS6KA2 and PCSK9 was observed within the cytoplasmic compartment of CRC cells. RPS6KA2 suppressed PCSK9 and MAPK signaling pathway in CRC cells. BI-D1780 which is an inhibitor of RPS6KA2 increased PCSK9 and MAPK signaling pathway related proteins expression in SW620 cells. However, an inhibitor or stimulator of MAPK did not affect RPS6KA2 and PCSK9 expression, respectively. In vivo, CRC cells with RPS6KA2 or PCSK9 overexpression could inhibit or promote tumor growth and metastasis, respectively. PCSK9 promoted proliferation, migration, and invasion of CRC cells. PCSK9 expression was higher in human CRC samples and associated with N classification and TNM stage of CRC. In conclusion, our study firstly suggests that ezetimibe suppresses CRC progression by upregulating RPS6KA2 while downregulating PCSK9/MAPK signaling pathway.

A disintegrin-like and metalloproteinase 15 facilitates glioblastoma proliferation and metastasis through activation of the protease-activated receptor 1

Objective

Glioblastoma hinders therapeutic interventions and prognostic outlooks. At the same time, a disintegrin-like and metalloproteinase 15 (ADAM15) influences cellular processes, such as adhesion and migration. Furthermore, protease-activated receptor 1 (PAR1), a vital receptor, impacts tumorigenesis and disease progression. This study aimed to investigate ADAM15 and PAR1 interaction in epithelial-mesenchymal transition (EMT) modulation in glioblastoma behavior and provide insights into therapeutic targets.

Material and Methods

The impacts of ADAM15 overexpression and PAR-1/2 inhibition on the proliferation, invasion, and migration of glioblastoma cells U251 and U87 were evaluated using transwell assays, EdU incorporation, clonogenic assay, Ki67 immunohistochemistry, and immunofluorescence staining. Real-time quantitative polymerase chain reaction and Western blot analysis were employed to investigate the impact of ADAM15 on PAR1 expression.

Results

After analyzing the impacts of ADAM15 overexpression on the migration, invasion, and proliferation of human glioblastoma cell lines U251 and U87, the results showed that ADAM15 overexpression significantly enhanced migration (P < 0.001) and invasion rates (P < 0.001), as confirmed by scratch and transwell assays, thus indicating its tumor-promoting effects. This study revealed a significant increase in colony formation (P < 0.001), EdU incorporation (P < 0.001), and Ki67-positive cells (P < 0.001) in the ADAM15 overexpressed group. PAR1 and EMT markers were significantly increased in the ADAM15 overexpressed group (P < 0.001). Treatment with the PAR-1 antagonist SCH79797 inhibited EMT (P < 0.01) and suppressed cell proliferation (P < 0.001), migration (P < 0.001), and invasion (P < 0.001) in U251 and U87 cells overexpressing ADAM15, indicating the involvement of PAR-1 signaling in the effects of ADAM15 on cell behaviors. In comparison, the PAR-2 antagonist FSLLRY-NH2 did not show significant effects on EMT or these cell behaviors.

Conclusion

ADAM15 drives glioblastoma cell lines U251 and U87 progression through PAR1.

Bletilla striata polysaccharide induces autophagy through PI3K/AKT signaling pathway to promote the survival of cross-boundary flap in rats

Introduction

Distal flap necrosis is a common problem in flap transplantation. Bletilla striata polysaccharide (BSP) is the main medicinal component of traditional Chinese medicine Bletilla striata. The purpose of this study was to investigate the mechanism of BSP promoting flap survival.

Methods

The control group, BSP low, medium and high dose groups, BSP + autophagy inhibitor 3-methyladenine (3-MA) group were designed to establish a model of cross-boundary flap in rat back. After 7 days of postoperative administration, the samples were taken.

Results

The optimal dose of BSP was determined to be 250 mg/kg/d according to the survival rate of flap, microvessel density, intra-arterial diameter, expression of vascular-related protein and pharmacological toxicity. By detecting the expression level of autophagy-related proteins, it was found that BSP could activate autophagy. After autophagy was blocked, the therapeutic effect of BSP was reversed. In addition, BSP activated the PI3K/AKT signaling pathway.

Discussion

Studies have shown that BSP induces autophagy by activating PI3K/AKT signaling pathway, thereby promoting angiogenesis and improving survival rate of flap.

Identification of lactylation-associated fibroblast subclusters predicting prognosis and cancer immunotherapy response in colon cancer

BACKGROUND

Lactylation plays an important role in tumor progression. This study aimed to clarify the impact of lactylation on cancer-associated fibroblasts(CAFs).

METHODS

Single-cell and bulk RNA sequence data, along with survival information, were obtained from TCGA and GEO datasets. Significant lactylation-associated genes were acquired by differential analysis and used to construct a prognostic model via Cox and LASSO regression analyses. Next, single-cell analysis, enrichment and pathway analysis, pseudotemporal trajectory and survival analysis were used to identify significant lactylation-associated fibroblast subclusters in colon cancer. IMvigor210 and PRJEB23709 cohorts were applied to assess the response to immunotherapy. In vitro experiments were conducted to explore how lactylation affect fibroblasts.

RESULTS

We established a lactylation-associated prognostic model with 17 risk genes in TCGA and further validated it in GEO datasets. Single-cell analysis revealed the lactylation level of fibroblasts in colon cancer was greater than that in normal tissues. Moreover, five lactylation-associated fibroblast subclusters were identified via the NMF algorithm. Patients with lower scores of FB_2_CALD1, FB_3_TPM4 and FB_4_AHNAK subclusters had better clinical prognosis in colon cancer and were more likely to benefit from immunotherapy. Further experiments demonstrated that lactylation could enhance the proliferation, migration and invasion ability of fibroblasts and up-regulate the expression of COL1A1, which was similar to the effect of colon cancer cells.

CONCLUSION

This study identified key fibroblast subclusters with prognostic value and implied that lactylation might help transform fibroblasts into CAFs in colon cancer for the first time, which provides new paths for understanding the evolution of CAFs and cancer therapeutic strategies.

Reduced SMEK1 regulates trophoblast migration and invasion in fetal growth restriction

INTRODUCTION

Fetal growth restriction (FGR) is a significant pregnancy condition characterized by the fetus failing to attain its full genetic growth potential. FGR is primarily ascribed to defective placentation, owing to impaired trophoblast cellular function. The objective of this research is to elucidate the pathogenic functions of suppressor of Mek1 (SMEK1) in FGR.

METHODS

Western blot and Immunofluorescence were used to detect the expression and localization of SMEK1 in placenta. We overexpressed and knocked down SMEK1 using plasmid or siRNA special targeted it. EdU Assay, flow cytometry, Western blot, Wound healing migration and Transwell insert assay were used to detect the influence of SMEK1 on cellular function. The mechanism of SMEK1 in regulating the migration of JEG3 cells was predicted by employing transcriptomics and bioinformatics analysis, and was validated by Western blot.

RESULTS

The expression of SMEK1 was downregulated in FGR placentas. The aberrant expression of SMEK1 in JEG3 cells is associated with cell migration and invasion, but not with proliferation, or apoptosis. Transcriptomic analysis and Western blots indicate that knockdown of SMEK1 inhibited the PI3K/Akt/mTOR pathway. A significant inhibition was observed in the epithelial-mesenchymal transition (EMT) process of JEG3 cells within the SMEK1 knockdown group. The activation of the PI3K/Akt/mTOR pathway partially restored the impaired migration and invasive ability due to SMEK1 knockdown in JEG3 cells.

DISCUSSION

the reduction of SMEK1 may contribute to the development of FGR by hindering the EMT process of trophoblast cells through modulation of the PI3K/Akt/mTOR signaling pathway.

Effects of PCSK9 inhibitors on cancer, diabetes, and cardiovascular diseases

Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) have potential applications in cancer therapy and as cholesterol-lowering treatments. The impact of PCSK9 suppression on both tumor growth and metastasis, as well as the management of diabetes, has been demonstrated. PCSK9i can also enhance outcomes and reduce cardiovascular (CV) events in individuals with a history of such events. In this review, we provide insights into the pharmacology, safety, and impact of PCSK9i. We highlight cutting-edge investigations, the development of innovative PCSK9i-based products, and a more comprehensive understanding of the potential effects of these drugs on cancer, diabetes, and CV and cerebrovascular diseases.

Trametinib alleviates lipopolysaccharide-induced acute kidney injury by inhibiting macrophage polarization through the PI3K/Akt pathway

BACKGROUND

Sepsis-induced acute kidney injury (AKI) is a severe condition characterized by dysregulation of pro- and anti-inflammatory responses. Targeting macrophage polarization between pro-inflammatory M1 and anti-inflammatory M2 cells offers a potential therapeutic approach for AKI. Trametinib (TRAM), an inhibitor of the MEK1/2 signaling pathway, was evaluated for its impact on M1/M2 polarization in AKI.

METHODS

Wild-type (WT) mice were subjected to lipopolysaccharide (LPS)-induced AKI and intraperitoneally treated with dimethyl sulfoxide (DMSO) or TRAM (10 mg/kg) for three days. Renal function was assessed by measuring creatinine levels. While histopathological changes, RNA sequencing data, and serum cytokine levels were analyzed. Macrophage M1/M2 polarization in kidney tissues was examined using flow cytometry and immunohistochemistry. Murine bone marrow-derived macrophages (BMDMs) were polarized to the M1 or M2 phenotype in vivo and treated with or without TRAM (10 μM). M1/M2 polarization was analyzed via flow cytometry, and PI3K/Akt signaling was evaluated by western blotting.

RESULTS

TRAM significantly improved renal function, as demonstrated by reduced serum creatinine levels (p < 0.01) and ameliorated histopathological damage (p < 0.01). Flow cytometry and immunohistochemistry revealed that TRAM markedly inhibited pro-inflammatory M1 macrophage polarization (p < 0.001). Additionally, TRAM reduced serum level of IFN-γ (p < 0.01) and IL-17 (p < 0.001). In vitro, TRAM suppressed M1 polarization (p < 0.05) by inhibiting the PI3K/Akt signaling pathway.

CONCLUSION

TRAM mitigated LPS-induced AKI by suppressing M1 macrophage polarization via the PI3K/Akt pathway, highlighting its therapeutic potential for AKI and other inflammatory kidney diseases.

Tumor Metastasis: Mechanistic Insights and Therapeutic Intervention

Metastasis remains a leading cause of cancer‐related deaths, defined by a complex, multi‐step process in which tumor cells spread and form secondary growths in distant tissues. Despite substantial progress in understanding metastasis, the molecular mechanisms driving this process and the development of effective therapies remain incompletely understood. Elucidating the molecular pathways governing metastasis is essential for the discovery of innovative therapeutic targets. The rapid advancements in sequencing technologies and the expansion of biological databases have significantly deepened our understanding of the molecular drivers of metastasis and associated drug resistance. This review focuses on the molecular drivers of metastasis, particularly the roles of genetic mutations, epigenetic changes, and post‐translational modifications in metastasis progression. We also examine how the tumor microenvironment influences metastatic behavior and explore emerging therapeutic strategies, including targeted therapies and immunotherapies. Finally, we discuss future research directions, stressing the importance of novel treatment approaches and personalized strategies to overcome metastasis and improve patient outcomes. By integrating contemporary insights into the molecular basis of metastasis and therapeutic innovation, this review provides a comprehensive framework to guide future research and clinical advancements in metastatic cancer.

PCSK9 affects vascular senescence through the SIRT1 pathway

Age is an independent risk factor for atherosclerotic cardiovascular disease that increases the susceptibility of older adults to vascular intimal thickening, endothelial dysfunction, and thrombosis. However, the mechanism underlying vascular injury is not fully understood. In the present study, the effect of proprotein convertase subtilin-type kexin 9 (PCSK9) inhibitors on the senescent state of human umbilical vein endothelial cells (HUVECs) and on senescent mice and lipopolysaccharides (LPS) were assessed. The senescent state of mice was delayed under PCSK9 inhibitor treatment, and the expression of P16, P21, and P53 proteins in senescent cells was increased because LPS induction stimulated PCSK9 activation. PCSK9 overexpression accelerated cell senescence, activated a large number of oxidative stress pathways, and increased the expression of senescence-related genes (including P16, P21, and P53). In addition, inhibition of the sirtuin 1 (SIRT)1 oxidative stress pathway can attenuate the aging-promoting effects of PCSK9, which are elevated as a result of LPS induction. The SIRT1 activator was more efficient than LPS alone in inducing the expression of senescence-related genes. Therefore, PCSK9 inhibitors can delay the aging of the vascular by reducing cellular SIRT1 levels. Therefore, it can be concluded that PCSK9 inhibition inhibits vascular senescence by reducing the expression of senescent proteins by regulating the SIRT1 pathway.

Advancements in omics technologies: Molecular mechanisms of acute lung injury and acute respiratory distress syndrome (Review)

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is an inflammatory response arising from lung and systemic injury with diverse causes and associated with high rates of morbidity and mortality. To date, no fully effective pharmacological therapies have been established and the relevant underlying mechanisms warrant elucidation, which may be facilitated by multi‑omics technology. The present review summarizes the application of multi‑omics technology in identifying novel diagnostic markers and therapeutic strategies of ALI/ARDS as well as its pathogenesis.

Up-regulation of m6A writer METTL14 inhibits tumorigenesis by suppressing glycolysis in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a common malignant tumor. N6-Methyladenosine (m6A) modification plays an important role in the regulation of glycolysis in tumor cells and may be a potential target for tumor therapy.

METHODS

The role of METTL14, an m6A writer, in CRC was investigated through functional assays including cell viability, colony formation, and glycolysis-related measurements (glucose uptake, lactate production, extracellular acidification rate (ECAR) and oxygen consumption rate (OCR)). The target gene regulated by METTL14 in an m6A-dependent manner was identified using molecular biology techniques. In addition, CRC cells overexpressing METTL14 were subcutaneously injected into mice to verify the regulatory effect of METTL14 on tumor growth in vivo.

RESULTS

Our data suggested that METTL14 was up-regulated in CRC cell lines, and over-expression of METTL14 suppressed cell proliferation and glycolysis. Meanwhile, ATF2 m6A level was significantly up-regulated by over-expression of METTL14, and the binding relationship between ATF2 and METTL14 was further verified. METTL14-m6A regulated ATF2 in CRC cells participates in the regulation of glycolysis. METTL14 also suppressed tumorigenesis of nude mice.

CONCLUSION

Intervention with METTL14 mediated m6A modifications or its associated protein ATF2 may provide new strategies for CRC therapy.

The role of MUC16 in tumor biology and tumor immunology in ovarian cancer

In this study, the influence of glycoproteomic changes, specifically MUC16, on NK cell-mediated immunotherapy response in ovarian cancer is explored. Analysis of glycoprotein data from the CPTAC database identified significant upregulation of MUC16 in ovarian cancer tissues, associated with tumor invasiveness and immune evasion. Experimental findings showed that MUC16 knockdown increased NK cell cytotoxicity, decreased invasiveness, and boosted NK cell activation, while MUC16 overexpression resulted in the opposite effects. In vivo experiments demonstrated that MUC16 knockdown suppressed tumor growth, enhanced NK cell infiltration, and bolstered NK cell activation, underscoring the potential of MUC16 as a target for novel immunotherapy approaches in ovarian cancer treatment.

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.

The role of natural products targeting macrophage polarization in sepsis-induced lung injury

Sepsis-induced acute lung injury (SALI) is characterized by a dysregulated inflammatory and immune response. As a key component of the innate immune system, macrophages play a vital role in SALI, in which a macrophage phenotype imbalance caused by an increase in M1 macrophages or a decrease in M2 macrophages is common. Despite significant advances in SALI research, effective drug therapies are still lacking. Therefore, the development of new treatments for SALI is urgently needed. An increasing number of studies suggest that natural products (NPs) can alleviate SALI by modulating macrophage polarization through various targets and pathways. This review examines the regulatory mechanisms of macrophage polarization and their involvement in the progression of SALI. It highlights how NPs mitigate macrophage imbalances to alleviate SALI, focusing on key signaling pathways such as PI3K/AKT, TLR4/NF-κB, JAK/STAT, IRF, HIF, NRF2, HMGB1, TREM2, PKM2, and exosome-mediated signaling. NPs influencing macrophage polarization are classified into five groups: terpenoids, polyphenols, alkaloids, flavonoids, and others. This work provides valuable insights into the therapeutic potential of NPs in targeting macrophage polarization to treat SALI.

Integrative bioinformatics and experimental analyses identify U2SURP as a novel lactylation-related prognostic signature in esophageal carcinoma

The lactylation modification has been implicated in several cancer types; however, the role of lactylation modification-related genes in esophageal carcinoma (EC) remains underexplored. Utilizing a set of 16 lactylation modification-related genes, cohorts of patients with EC were stratified into two distinct clusters, characterized by significant disparities in both survival outcomes and the immune microenvironment. An extensive bioinformatics analysis unveiled 382 differentially expressed genes (DEGs) between these two clusters. A subsequent univariate Cox regression analysis identified 24 DEGs specifically associated with lactylation, forming the basis of a constructed lactylation-related score. The resultant lactylation-related score exhibited notable predictive efficacy for survival and other clinicopathological traits, which was validated through calibration curves, Kaplan-Meier survival curves and the Wilcoxon test. Moreover, the lactylation-related score displayed a close correlation with immune cell infiltration in EC. Notable differential expressions of immune checkpoints and regulators were observed between groups stratified by low and high lactylation scores, with the latter exhibiting a more favorable response to anti-PD-1/PD-L1 therapy. Furthermore, the expression profile of U2 snRNP associated SURP domain containing (U2SURP), a constituent of the lactylation-related score, underwent both ex vivo and in vitro validation. The expression of U2SURP was significantly associated with lactylation levels, histological grade and tumor stage. Notably, knockdown of U2SURP expression inhibited the lactylation levels, immune genes IL-1A and IL-1B, proliferation, migration and invasion of EC cells. In conclusion, the lactylation-related score developed in the present study showed promise in predicting the prognosis and immunotherapeutic responses among patients with EC. Moreover, the identification of U2SUPR as a novel oncogene in EC suggests its potential as a prospective therapeutic target for EC treatment.

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.

[Construction and Validation of A Prognostic Model for Lung Adenocarcinoma Based on Ferroptosis-related Genes]

BACKGROUND

Ferroptosis-related genes play a crucial role in regulating intracellular iron homeostasis and lipid peroxidation, and they are involved in the regulation of tumor growth and drug resistance. The expression of ferroptosis-related genes in tumor tissues can be used to predict patients' future survival times, aiding doctors and patients in anticipating disease progression. Based on the sequencing data of lung adenocarcinoma (LUAD) patients from The Cancer Genome Atlas (TCGA) database, this study identified genes involved in the regulation of ferroptosis, constructed a prognostic model, and evaluated the predictive performance of the model.

METHODS

A total of 1467 ferroptosis-related genes were obtained from the GeneCards database. Gene expression profiles and clinical data from 541 LUAD patients were collected from the TCGA database. The expression data of all ferroptosis-related genes were extracted, and differentially expressed genes were identified using R software. Survival analysis was performed on these genes to screen for those with prognostic value. Subsequently, a prognostic risk scoring model for ferroptosis-related genes was constructed using LASSO regression model. Each LUAD patient sample was scored, and the patients were divided into high-risk and low-risk groups based on the median score. Receiver operating characteristic (ROC) curves were plotted, and the area under the curve (AUC) was calculated. Kaplan-Meier survival curves were generated to assess model performance, followed by validation in an external dataset. Finally, univariate and multivariate Cox regression analyses were conducted to evaluate the independent prognostic value and clinical relevance of the model.

RESULTS

Through survival analysis, 121 ferroptosis-related genes associated with prognosis were initially identified. Based on this, a LUAD prognostic risk scoring model was constructed using 12 ferroptosis-related genes (ALG3, C1QTNF6, CCT6A, GLS2, KRT6A, LDHA, NUPR1, OGFRP1, PCSK9, TRIM6, IGF2BP1 and MIR31HG). The results indicated that patients in the high-risk group had significantly shorter survival time than those in the low-risk group (P<0.001), and the model demonstrated good predictive performance in both the training set (1-yr AUC=0.721) and the external validation set (1-yr AUC=0.768). Risk scores were significantly associated with the prognosis of LUAD patients in both univariate and multivariate Cox regression analyses (P<0.001), suggesting that this score is an important prognostic factor for LUAD patients.

CONCLUSIONS

This study successfully established a LUAD risk scoring model composed of 12 ferroptosis-related genes. In the future, this model is expected to be used in conjunction with the tumor-node-metastasis (TNM) staging system for prognostic predictions in LUAD patients.

Insight into the roles of lactylation in macrophages: functions and clinical implications

Lactylation, a post-translational modification, has been linked to gene transcription regulation through epigenetic modulation in various pathophysiological processes. The lactylation regulatory proteins, known as writers, erasers, and readers, govern their dynamics by adding, removing, and recognizing lactyl groups on proteins. Macrophages, as cells of the immune system, maintain homeostasis, responding dynamically to diverse internal and external stimuli. Emerging researches unveil that lactylation, through inducing macrophage activation and polarization, affects their functionality in pathological conditions such as inflammation, tumor microenvironment, and fibrosis. Evidence progressively indicates that lactate-driven alterations in lactylation levels within macrophages can influence the pathogenesis of numerous diseases. This review aims to systematically summarize the research progress of lactylation in macrophages, explore its functions and mechanisms by which lactylation contributes to the pathology of different disease phenotypes, and propose future research directions along with potential diagnostic and therapeutic strategies.

Lactylation in health and disease: physiological or pathological?

Lactate is an indispensable substance in various cellular physiological functions and plays regulatory roles in different aspects of energy metabolism and signal transduction. Lactylation (Kla), a key pathway through which lactate exerts its functions, has been identified as a novel posttranslational modification (PTM). Research indicates that Kla is an essential balancing mechanism in a variety of organisms and is involved in many key cellular biological processes through different pathways. Kla is closely related to disease development and represents a potential and important new drug target. In line with existing reports, we searched for newly discovered Kla sites on histone and nonhistone proteins; reviewed the regulatory mechanisms of Kla (particularly focusing on the enzymes directly involved in the reversible regulation of Kla, including "writers" (modifying enzymes), "readers" (modification-binding enzymes), and "erasers" (demodifying enzymes); and summarized the crosstalk between different PTMs to help researchers better understand the widespread distribution of Kla and its diverse functions. Furthermore, considering the "double-edged sword" role of Kla in both physiological and pathological contexts, this review highlights the "beneficial" biological functions of Kla in physiological states (energy metabolism, inflammatory responses, cell fate determination, development, etc.) and its "detrimental" pathogenic or inducive effects on pathological processes, particularly malignant tumors and complex nontumor diseases. We also clarify the molecular mechanisms of Kla in health and disease, and discuss its feasibility as a therapeutic target. Finally, we describe the detection technologies for Kla and their potential applications in diagnosis and clinical settings, aiming to provide new insights for the treatment of various diseases and to accelerate translation from laboratory research to clinical practice.

Silencing PPAP2C inhibits lung adenocarcinoma migration and invasion via the ERK/JNK pathway

Lung adenocarcinoma (LUAD) is a leading cause of cancer‑related death due to its aggressive nature and metastatic potential. The present study aimed to explore the expression of phospholipid phosphatase 2 (PPAP2C) in LUAD, and its effect on cell migration and invasion, with a particular focus on its association with the ERK/JNK signaling pathway and epithelial‑mesenchymal transition (EMT). The expression of PPAP2C in LUAD was analyzed using data from The Cancer Genome Atlas database. Pearson's correlation coefficient analysis was used to assess the correlation between PPAP2C and genes such as MAPK1, MAPK3, MAPK8, CDH1, CDH2 and SNAI1. Subsequently, the PPAP2C gene was silenced in A549 and H1299 LUAD cell lines using siRNA vectors, followed by assessments of gene expression, cell migration, invasion and protein interaction using reverse transcription‑quantitative PCR, western blotting, wound healing assay, Transwell invasion assay, molecular docking analysis, co‑immunoprecipitation and immunofluorescence staining. The results showed that PPAP2C was significantly upregulated in LUAD tissues compared with that in normal tissues. In addition, high levels of PPAP2C were significantly correlated with MAPK3, MAPK8, CDH1 and SNAI1. Notably, PPAP2C silencing significantly inhibited cell migration and invasion. Additionally, it reduced the phosphorylation levels of ERK and JNK proteins. PPAP2C showed specific binding sites with ERK1, and co‑precipitated with ERK1 in both A549 and H1299 cells. Furthermore, PPAP2C silencing decreased the expression levels of N‑cadherin and Snail, while increasing E‑cadherin expression, thereby inhibiting EMT. In conclusion, PPAP2C may be highly expressed in LUAD tissues, and could promote cell migration and invasion by activating the ERK/JNK signaling pathway and inducing EMT. These findings provide a novel potential target for the diagnosis and treatment of LUAD.

Interplay between lncRNAs and the PI3K/AKT signaling pathway in the progression of digestive system neoplasms (Review)

Long non‑coding RNA (lncRNA) is a class of non‑coding RNA molecules located in the cytoplasm or nucleus, which can regulate chromosome structure and function by interacting with DNA, RNA, proteins and other molecules; binding to mRNA bases in a complementary manner, affecting the splicing, stabilization, translation and degradation of mRNA; acting as competing endogenous RNA competitively binds to microRNAs to regulate gene expression and participate in the regulation of various vital activities of the body. The PI3K/AKT signalling pathway plays a key role in numerous biological and cellular processes, such as cell proliferation, invasion, migration and angiogenesis. It has been found that the lncRNA/PI3K/AKT axis regulates the expression of cancer‑related genes and thus tumour progression. The abnormal regulation of lncRNA expression in the lncRNA/PI3K/AKT axis is clearly associated with clinicopathological features and plays an important role in regulating biological functions. In the present review, the expression and biological functions of PI3K/AKT‑related lncRNAs both in vitro and in vivo over recent years, were comprehensively summarized and analyzed. Their correlation with clinicopathological features was also evaluated, with the objective of furnishing a solid theoretical foundation for clinical diagnosis and the monitoring of efficacy in digestive system neoplasms. The present review aimed to provide a comprehensive overview of the expression and biological functions of PI3K/AKT‑related lncRNAs in digestive system neoplasms and to assess their correlation with clinicopathological features. This endeavor seeks to establish a solid theoretical foundation for the clinical diagnosis and efficacy monitoring of digestive system tumors.

FGF19 is a biomarker associated with prognosis and immunity in colorectal cancer

OBJECTIVE

This study aimed to investigate the relationship between fibroblast growth factor 19 (FGF19) and the prognosis and immune infiltration of colorectal cancer (CRC) and identify the related genes and pathways influencing the onset and progression of CRC.

INTRODUCTION

The potential of FGF19 to guide the prognosis of CRC and inform immunotherapeutic strategies warrants further investigation.

METHODS

We performed Quantitative Real-Time PCR to assess the expression of FGF19 and conducted a bioinformatics analysis to evaluate the impact of FGF19 expression on the clinical prognosis of CRC. We also analyzed the association between FGF19 expression and immune cell infiltration in CRC, and explored the related genes and pathways through which FGF19 influences CRC development.

RESULTS

CRC patients with higher FGF19 expression exhibited a poorer prognosis. In terms of the Receiver Operating Characteristic (ROC), FGF19 achieved an area under the curve (AUC) of 0.904. FGF19 expression correlated with the N stage, M stage, and pathological stage in patients with CRC. Functional enrichment analysis revealed significant enrichment of FGF19 in pathways associated with tumor development. ssGSEA and Spearman correlation analysis demonstrated that FGF19 expression was linked to tumor immune cells. We discovered that FGF19 is closely related to neutrophil extracellular traps (NETs), which play a significant role in the immune microenvironment.

CONCLUSION

FGF19 is a key gene associated with immunity and prognosis in CRC patients. Our findings suggest that FGF19 may influence CRC progression by promoting NETs expression, which leads to suppression of immune cells.

PCSK9 induces endothelial cell autophagy by regulating the PI3K/ATK pathway in atherosclerotic coronary heart disease

OBJECTIVE

Atherosclerosis is a chronic inflammatory disease of the arteries, and its pathogenesis is related to endothelial dysfunction. It has been found that the protein convertase subtilin/kexin9 type (PCSK9) plays an important role in AS, but its specific mechanism is still unclear.

METHODS

In this study, we first cultured human umbilical vein endothelial cells (HUVECs) with 50 or 100μg/ml oxidized low-density lipoprotein (ox-LDL) for 24 hours to establish a coronary atherosclerosis cell model.

RESULTS

The results showed that ox-LDL induced HUVEC injury and autophagy and upregulated PCSK9 protein expression in HUVECs in a concentration-dependent manner. Silencing PCSK9 expression with siRNA inhibited ox-LDL-induced HUVEC endothelial dysfunction, inhibited the release of inflammatory factors, promoted HUVEC proliferation and inhibited apoptosis. In addition, ox-LDL increased the expression of LC3B-I and LC3B-II and decreased the expression of p62. However, these processes are reversed by sh-PCSK9. In addition, sh-PCSK9 can inhibit PI3K, AKT and mTOR phosphorylation and promote autophagy.

CONCLUSION

Taken together, our research shows that silencing PCSK9 inhibits the PI3K/ATK/mTOR pathway to activate ox-LDL-induced autophagy in vascular endothelial cells, alleviating endothelial cell injury and inflammation.

Plasma-activated medium suppresses proliferation and migration of human lung cancer cells by regulating PI3K/AKT-Wnt signaling pathway

The main causes of high mortality in lung cancer patients are the malignant growth and migration of cancer cells. This study aims to investigate the underlying mechanisms of low-temperature plasma-activated medium (PAM) treating human lung cancer (HLC). Changes in the levels of reactive oxygen and nitrogen species both inside and outside the cells were evaluated. Our results showed that prolonged PAM exposure decreased cell viability, raised intracellular reactive oxygen species levels, and hindered cell migration while reducing mitochondrial membrane potential. Protein analysis revealed PAM increased GSK-3β and p-β-catenin expression but decreased PI3K, AKT, p-AKT, p-GSK-3β, Wnt, and β-catenin levels, thereby inhibiting the epithelial-mesenchymal transition. These findings suggest PAM suppresses HLC cells proliferation and migration by blocking the PI3K/AKT-Wnt pathway. The study will provide a valuable theoretical basis for future low-temperature plasma treatment, thereby improving the survival rates and prognosis of lung cancer.

Impact of immunosuppressants on tumor pulmonary metastasis: new insight into transplantation for hepatocellular carcinoma

Pulmonary metastasis is a life-threatening complication for patients with hepatocellular carcinoma (HCC) undergoing liver transplantation (LT). In addition to the common mechanisms underlying tumor metastasis, another inevitable factor is that the application of immunosuppressive agents, including calcineurin inhibitors (CNIs) and rapamycin inhibitors (mTORis), after transplantation could influence tumor recurrence and metastasis. In recent years, several studies have reported that mTORis, unlike CNIs, have the capacity to modulate the tumorigenic landscape post-liver transplantation by targeting metastasis-initiating cells and reshaping the pulmonary microenvironment. Therefore, we focused on the effects of immunosuppressive agents on the lung metastatic microenvironment and how mTORis impact tumor growth in distant organs. This revelation has provided profound insights into transplant oncology, leading to a renewed understanding of the use of immunosuppressants after LT for HCC.

Comprehensive analysis identifies a lactylation-related signature for predicting prognosis and guiding therapies in colon adenocarcinoma

PURPOSE

This study aimed to identify a lactylation-related gene signature for predicting prognosis and guiding therapies in colon adenocarcinoma (COAD). We seek to address the challenges in COAD prognostication due to tumor heterogeneity and variable treatment responses.

METHODS

The study employed integrative bioinformatics analyses on multi-omics data from public databases, including gene expression profiles, clinical data, and lactylation-related genes (LRGs). The least absolute shrinkage and selection operator (LASSO) regression analysis and Cox risk model were applied to develop a prognostic signature. The predictive capabilities of the signature were assessed in four independent COAD cohorts (GSE39582, GSE71187, GSE75500, and GSE17536). Functional enrichment, immune infiltrations, and scRNA-seq analysis were performed to investigate biological processes and the tumor microenvironment (TME). Additionally, functional assays were performed to assess the impact of gene knockdown on COAD cell behavior.

RESULTS

A 3-gene signature (SUSD5, FABP4, CALB2) was identified, demonstrating robust predictive performance for clinical outcomes in COAD patients across multiple cohorts. The signature revealed involvement in critical cancer-related biological processes and showed potential in guiding therapeutic decisions. The bulk RNA-seq and scRNA-seq analysis suggested that LRGs modulates the TME, particularly immune cell populations like mast cells. Knockdown of CALB2 significantly suppressed COAD cell proliferation, invasion, and migration.

CONCLUSION

This comprehensive analysis identified a lactylation-related signature with significant prognostic and therapeutic implications for COAD. The findings highlight the importance of lactylation in COAD biology and offer novel insights for developing personalized treatment strategies, potentially improving patient outcomes in this prevalent malignancy.

Lactate and Lactylation: Dual Regulators of T-Cell-Mediated Tumor Immunity and Immunotherapy

Lactate and its derivative, lactylation, play pivotal roles in modulating immune responses within the tumor microenvironment (TME), particularly in T-cell-mediated cancer immunotherapy. Elevated lactate levels, a hallmark of the Warburg effect, contribute to immune suppression through CD8+ T cell functionality and by promoting regulatory T cell (Treg) activity. Lactylation, a post-translational modification (PTM), alters histone and non-histone proteins, influencing gene expression and further reinforcing immune suppression. In the complex TME, lactate and its derivative, lactylation, are not only associated with immune suppression but can also, under certain conditions, exert immunostimulatory effects that enhance cytotoxic responses. This review describes the dual roles of lactate and lactylation in T-cell-mediated tumor immunity, analyzing how these factors contribute to immune evasion, therapeutic resistance, and immune activation. Furthermore, the article highlights emerging therapeutic strategies aimed at inhibiting lactate production or disrupting lactylation pathways to achieve a balanced regulation of these dual effects. These strategies offer new insights into overcoming tumor-induced immune suppression and hold the potential to improve the efficacy of cancer immunotherapies.

Comprehensive Mendelian randomization analysis of low-density lipoprotein cholesterol and multiple cancers

PURPOSE

The aim of this study was to investigate the causal relationship between low-density lipoprotein cholesterol (LDL-C) and five cancers (breast, cervical, thyroid, prostate and colorectal) using the Mendelian Randomization (MR) method, with a view to revealing the potential role of LDL-C in the development of these cancers.

METHODS

We used gene variant data and disease data from the Genome-Wide Association Study (GWAS) database to assess the causal relationship between LDL-C and each cancer by Mendelian randomisation analysis methods such as inverse variance weighting and MR-Egger. Specifically, we selected Proprotein convertase subtilisin/kexin type 9 (PCSK9) and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), genes associated with LDL-C levels, as instrumental variables, extracted the corresponding single nucleotide polymorphism (SNP) data and analysed the associations of these SNPs with five cancers.In addition, sensitivity analyses and heterogeneity tests were performed to ensure the reliability of the results.

RESULTS

The analyses showed that when using HMGCR gene, LDL-C were significantly and positively associated with breast (OR:1.200, 95% CI:1.082-1.329, p = 0.001), prostate (OR:1.198, 95% CI:1.050-1.366, p = 0.007), and thyroid cancers (OR:8.291, 95% CI:3.189- 21.555, p = 0.00001) were significantly positively correlated, whereas they were significantly negatively correlated with colorectal cancer (OR:0.641, 95% CI:0.442-0.928, p = 0.019); the results for cervical cancer were not significant (p = 0.050). When using the PCSK9 gene, LDL-C levels were significantly and positively associated with breast (OR:1.107, 95%:CI 1.031-1.187, p = 0.005) and prostate (OR:1.219, 95%:CI 1.101-1.349, p = 0.0001) cancers, but not with cervical (p = 0.294), thyroid cancer (p = 0.759) and colorectal cancer ( p = 0.572).

CONCLUSION

Analyses using both the HMGCR and PCSK9 genes have shown that LDL-C may be a potential risk factor for breast and prostate cancer, while analyses of the HMGCR gene have also suggested that LDL-C may increase the risk of thyroid cancer and decrease the risk of colorectal cancer.

PCSK9 inhibitor alleviates experimental pulmonary fibrosis-induced pulmonary hypertension via attenuating epithelial-mesenchymal transition by suppressing Wnt/β-catenin signaling in vivo and in vitro

Background

The co-occurrence of pulmonary hypertension (PH) in patients with pulmonary fibrosis (PF) is linked to a more unfavorable prognosis and increased mortality compared to PF cases without PH. Early intervention and comprehensive management are pivotal for improving survival outcomes. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a protein essential in cholesterol metabolism. However, the potential for PCSK9 inhibition to alleviate PF-induced PH has not been previously reported.

Methods

A mouse model of PF-induced PH was established using intratracheal injection of bleomycin (BLM), followed by administration of a PCSK9 inhibitor every other day. Data on right ventricle (RV) remodeling and changes in pulmonary arteries were collected and analyzed. Transforming growth factor-beta (TGF-β) was also administered to MLE-12 cells as an experimental lung fibrosis model. The mechanisms of PCSK9's impact on lung fibrosis were examined both in vivo and in vitro.

Results

Inhibition of PCSK9 significantly reduced pulmonary artery thickening and RV remodeling in the BLM-induced mouse model. Moreover, the blockage of PCSK9 effectively attenuated the migration and epithelial-mesenchymal transition (EMT) process of TGF-β-induced MLE-12 cells. We also observed that the PCSK9 inhibitor suppressed the expression of the Wnt/β-catenin pathway in both animal and cell experiments.

Conclusion

PCSK9 plays a crucial role in the progression of PF-induced PH by regulating cell EMT and Wnt/β-catenin signaling. Targeting PCSK9 expression or activity could effectively control lung fibrosis and its PH complication.

Application of Macrophage Subtype Analysis in Acute Lung Injury/Acute Respiratory Distress Syndrome

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a common critical illness. Supportive therapy is still the main strategy for ALI/ARDS. Macrophages are the predominant immune cells in the lungs and play a pivotal role in maintaining homeostasis, regulating metabolism, and facilitating tissue repair. During ALI/ARDS, these versatile cells undergo polarization into distinct subtypes with significant variations in transcriptional profiles, developmental trajectory, phenotype, and functionality. This review discusses developments in the analysis of alveolar macrophage subtypes in the study of ALI/ARDS, and the potential value of targeting new macrophage subtypes in the diagnosis, prognostic evaluation, and treatment of ALI/ARDS.

Cancer-associated fibroblasts promote the proliferation and metastasis of colon cancer by mediating the RLIM/PML axis through paracrine COMP

BACKGROUND AND AIM

Cancer-associated fibroblasts (CAFs) are abundant in colon cancer (CC) patients with a poor prognosis. Here, the molecular regulatory mechanism of CAFs on CC growth and metastasis was explored.

METHODS

The genes' expression was monitored using RT-qPCR, immunoblotting, and immunohistochemistry. Cell viability and proliferation were found using CCK-8 and clone formation assays. The cell migration and invasion were probed using wound healing and Transwell. Co-IP was utilized for ascertaining the interaction between AKT and the ring finger protein, LIM domain interacting (RLIM). The in vivo murine subcutaneous tumor model and the metastasis model were built to further ascertain the axis.

RESULTS

The result showed that CAFs motivate the growth and activate the PI3K/AKT pathway of CC cells via paracrine cartilage oligomeric matrix protein (COMP). Moreover, RLIM promoted the growth of CC cells, and its protein stability was regulated by AKT through its phosphorylation. Further, RLIM facilitated the ubiquitination and degradation of promyelocytic leukemia protein (PML). The in vitro and in vivo tests found that PML overexpression could inhibit CC's growth and metastasis, which were enhanced by CAFs.

CONCLUSION

The COMP excreted from CAFs enhances the CC's growth and metastasis through regulating the RLIM/PML axis, supplying a new potential target for the cure of CC.

Endosulfan promotes cell growth, migration and invasion via CCL5/CCR5 axis in MCF-7 cells

Endosulfan, recognized as an endocrine disruptor, has emerged as an important risk factor for human breast cancer. The chemokine ligand 5 (CCL5) and its receptor CCR5 constitute a biological axis, that is implicated in tumorigenesis and cancer progression. However, the role of the CCL5/CCR5 axis in breast cancer when exposure to endosulfan remains unclear. The present study aimed to determine the significance of the CCL5/CCR5 axis in the carcinogenic effects of endosulfan in human breast cancer MCF-7 cells. The results showed that endosulfan significantly promoted cell proliferation, increased the rate of colony formation, and enhanced cell migration ability in a dose-dependent manner by activating the PI3K/AKT signaling pathway, which were rescued by the specific inhibitor (LY-294002) for PI3K/AKT signaling pathway. We utilized Cytoscape software to construct protein-protein interaction (PPI) network when exposure to endosulfan, and identified 47 highly connected genes in the network diagram centered on CCL5. Endosulfan significantly increased the secretion of CCL5 and the expression levels of CCL5/CCR5, which were reversed by CCR5 inhibitor (HY-13004). HY-13004 significantly counteracted the effects of endosulfan on colony formation, cell migration and the activation of PI3K/AKT signaling pathway. Endosulfan markedly altered the expression levels of epithelial-mesenchymal transition (EMT) biomarkers and enhanced transwell migration and invasion capabilities of MCF-7 cells, which were inhibited by HY-13004, similar to the effects observed with LY-294002. Collectively, our findings suggest that endosulfan activates the PI3K/AKT signaling pathway to promote cell growth, and induces EMT, thereby enhancing cell migration and invasion via the CCL5/CCR5 axis in MCF-7 cells.

Lactylation Modification as a Promoter of Bladder Cancer: Insights from Multi-Omics Analysis

Bladder cancer (BLAC) is a malignant tumor with high morbidity and mortality. The establishment of a prognostic model for BLAC is of great significance for clinical prognosis prediction and treatment guidance. Lactylation modification is a newly discovered post-transcriptional modification of proteins, which is closely related to the occurrence and development of tumors. Multiple omics data of BLAC were obtained from the GEO database and TCGA database. The Lasso algorithm was used to establish a prognostic model related to lactylation modification, and its predictive ability was tested with a validation cohort. Functional enrichment analysis, tumor microenvironment analysis, and treatment response evaluation were performed on the high- and low-risk groups. Single-cell and spatial transcriptome data were used to analyze the distribution characteristics of model genes and their changes during epithelial carcinogenesis. A prognostic model consisting of 12 genes was constructed. The survival rate of the high-risk group was significantly lower than that of the low-risk group. The multiple ROC curve showed that the prediction efficiency of the model was higher than that of the traditional clinical tumor grading. Functional enrichment analysis showed that glycolysis and hypoxia pathways were significantly upregulated in the high-risk group. The high-risk group was more sensitive to most first-line chemotherapy drugs, while the low-risk group had a better response to immunotherapy. Single-cell sequencing analysis revealed the dynamic changes of model genes during the transition of epithelial cells to squamous-differentiated cells. Spatial transcriptome analysis showed the spatial distribution characteristics of the model genes. The lactylation-related models have a satisfactory predictive ability and the potential to guide the clinical treatment of BLAC. This model has significant biological implications at the single-cell level as well as at the spatial level.

Recruitment and polarization typing of tumor-associated macrophages is associated with tumor progression and poor prognosis in Wilms tumor patients

PURPOSE

Tumor-associated macrophages (TAMs) play a crucial role in shaping various tumor microenvironments. However, their recruitment in Wilms tumor (WT), the predominant malignant renal tumor in children, has been inadequately explored. This retrospective cohort study involved the analysis of 148 WT samples to investigate the recruitment and polarization typing of TAMs in WT tissues.

METHODS

WT tissues underwent Western blotting (WB), reverse transcription-quantitative polymerase chain reaction (RT-qPCR), and immunofluorescence (IF) to measure the expression of TAM markers CD68, CD86, and CD163. Statistically analyze the relationship between TAM recruitment levels and patient clinical characteristics, and use Kaplan-Meier curves and the log-rank test to evaluate the association between TAM levels and survival outcomes.

RESULTS

The findings indicated a positive correlation between the recruitment levels of total macrophages (Mtotal) and M2 tumor-associated macrophages (M2 TAM) in both chemotherapy and non-chemotherapy groups with the clinical stage. Elevated recruitment of Mtotal and M2 TAM in tumor tissues was linked to a poorer prognosis. Notably, patients with persistently higher recruitment of M2 TAM following preoperative chemotherapy exhibited the worst prognosis.

CONCLUSIONS

The recruitment and polarization typing of TAM exhibit significant differences in WT patients with various stages and prognosis outcomes, suggesting a potential avenue for future diagnosis and treatment of WT.

LW-213, a derivative of wogonin, triggers reticulophagy-mediated cell death in NSCLC via lysosomal damage combined with NPC1 inhibition

BACKGROUND

Maintaining intracellular equilibrium is essential for the viability of tumor cells, which tend to be particularly vulnerable to environmental stressors. Consequently, targeting the disruption of this homeostasis offers a promising approach for oncological treatments. LW-213, a novel derivative of wogonin, effectively induces apoptosis in cancer cells by initiating endoplasmic reticulum (ER) stress, although the precise molecular pathways involved remain intricate and multifaceted.

PURPOSE

This research aimed to explore how LW-213 prompts apoptosis in non-small cell lung cancer (NSCLC) cells and to clarify the detailed mechanisms that govern this process.

METHODS

Various NSCLC cell lines were utilized to delineate the apoptotic effects induced by LW-213. Advanced methodologies, including RNA sequencing (RNA-seq), Western blotting (WB), immunofluorescence (IF), immunoprecipitation (IP), flow cytometry (Fc), real-time quantitative polymerase chain reaction (RT-qPCR), and electron microscopy, were employed to investigate the underlying molecular interactions. The efficacy and mechanistic action of LW-213 were also assessed in a xenograft model using nude mice.

RESULTS

We demonstrated that LW-213, a small molecule cationic amphiphilic drug (CAD), inhibited Niemann-Pick C1 (NPC1) function and induced lysosomal membrane damage, thereby activating the phosphoinositide-initiated membrane tethering and lipid transport (PITT) pathway. This activation promoted cholesterol transport from the ER to the lysosome, perpetuating a cholesterol-deficient state in the ER, including massive exocytosis of Ca2+ and activation of FAM134B-mediated reticulophagy. Ultimately, excessive reticulophagy induced lethal ER stress.

CONCLUSIONS

In summary, our study elucidates an organelle domino reaction initiated by lysosome damage and a series of self-rescue mechanisms that eventually lead to irreversible lethal effects, revealing a potential drug intervention strategy.

Targeting Mitochondrial Cholesterol Efflux via TCF21/ABCA10 Pathway to Enhance Cisplatin Efficacy in Ovarian Cancer

Cisplatin (DDP) resistance is one of the causes of treatment failure for ovarian cancer (OV). Mitochondrial cholesterol level was reported to be associated with OV chemoresistance. We found that ABCA10, a potential cholesterol transport protein, was highly expressed in ovarian tissues and downregulated in OV tissues. Our study aimed to explore TCF21/ABCA10 axis resistance to DDP therapy in ovarian cancer based on regulating mitochondrial cholesterol efflux. Thirty epithelial ovarian cancer tumors and thirty ovarian tissues from non-cancer patients were collected. Western blot and RT-qPCR were used to measure ABCA10 and TCF21 expression levels in these tissues, as well as in a human ovarian epithelial cell line (IOSE-80), OV cells (A2780 and SKOV3), and DDP-resistant OV cell lines (A2780/DDP and SKOV3/DDP). IOSE-80 cells were also infected with ABCA10 knockdown lentivirus to identify the most effective ABCA10 knockdown plasmid. Lentiviral infection was used to create ABCA10 knockdown, ABCA10 overexpression, and TCF21 overexpression anti-DDP OV cell lines. Cell proliferation was detected by CCK-8 and EDU staining, flow cytometry for apoptosis, MTT for metabolic activity, calcium-induced Cytochrome C release, and mitochondrial matrix swelling for mitochondrial function and Oil Red O staining for lipid accumulation. Cholesterol metabolism was evaluated by measuring mitochondrial cholesterol and cholesterol efflux. Protein concentration was determined using the BCA method. A dual-luciferase reporter assay confirmed TCF21's interaction with ABCA10. ChIP also verified this interaction. The mRNA level (P < 0.01) and protein level (P < 0.001) of ABCA10 were downregulated in cancer tissues of OV patients relative to normal ovarian tissues. Relative to human ovarian epithelial cells, ABCA10 expression was significantly downregulated in OV cells (P < 0.01) and even more significantly downregulated in DDP-resistant OV cells (P < 0.001). Compared to the group treated solely with DDP, the overexpression of ABCA10 significantly inhibited the proliferation of DDP-resistant OV cells (P < 0.01), markedly reduced the staining intensity of EDU in these cells (P < 0.05), and substantially accelerated apoptosis in DDP-resistant OV cells (P < 0.01).Overexpression of ABCA10 further accelerated Cytochrome C expression and mitochondrial matrix swelling in DDP-resistant OV cells compared to the DDP-alone group (P < 0.01). The addition of cholesterol reversed the decrease in lipid accumulation, the decrease in mitochondrial cholesterol levels (P < 0.05), and the increase in cholesterol efflux (P < 0.01) in DDP-resistant OV cells caused by overexpression of ABCA10. The transcription factor TCF21 was bound to the promoter of ABCA10. Overexpression of TCF21 significantly increased ABCA10 expression in DDP-resistant OV cells (P < 0.01) and increased cytochrome C expression in A2780/DDP (P < 0.05) and SKOV3/DDP (P < 0.01) cells, with accelerated mitochondrial matrix swelling in A2780/DDP (P < 0.01) and SKOV3/DDP (P < 0.001) cells, while knockdown of ABCA10 reversed these effects. Our study found that TCF21 boosts ABCA10 expression, which in turn reduces DDP resistance in OV cells by enhancing mitochondrial cholesterol efflux. This mechanism increases the sensitivity of DDP-resistant OV cells to DDP. Our findings will provide new therapeutic targets for the treatment of ovarian cancer.

Multi-omics reveals lactylation-driven regulatory mechanisms promoting tumor progression in oral squamous cell carcinoma

BACKGROUND

Lactylation, a post-translational modification, is increasingly recognized for its role in cancer progression. This study investigates its prevalence and impact in oral squamous cell carcinoma (OSCC).

RESULTS

Immunohistochemical staining of 81 OSCC cases shows lactylation levels correlate with malignancy grading. Proteomic analyses of six OSCC tissue pairs reveal 2765 lactylation sites on 1033 proteins, highlighting its extensive presence. These modifications influence metabolic processes, molecular synthesis, and transport. CAL27 cells are subjected to cleavage under targets and tagmentation assay for accessible-chromatin with high-throughput sequencing, and transcriptomic sequencing pre- and post-lactate treatment, with 217 genes upregulated due to lactylation. Chromatin immunoprecipitation-quantitative PCR and real-time fluorescence quantitative PCR confirm the regulatory role of lactylation at the K146 site of dexh-box helicase 9 (DHX9), a key factor in OSCC progression. CCK8, colony formation, scratch healing, and Transwell assays demonstrate that lactylation mitigates the inhibitory effect of DHX9 on OSCC, thereby promoting its occurrence and development.

CONCLUSIONS

Lactylation actively modulates gene expression in OSCC, with significant effects on chromatin structure and cellular processes. This study provides a foundation for developing targeted therapies against OSCC, leveraging the role of lactylation in disease pathogenesis.

Incomplete Thermal Ablation-Induced FOXP4-Mediated Promotion of Malignant Progression in Liver Cancer via NDST2

Purpose

The explosive progression of residual hepatocellular carcinoma (HCC) following incomplete thermal ablation is challenging, and the underlying mechanisms require further exploration. We investigated the mechanism by which Forkhead box P4 (FOXP4) promotes the malignant transformation of residual HCC cells through N-deacetylase and N-sulfotransferase 2 (NDST2) after incomplete thermal ablation.

Methods

The clinical significance of FOXP4 and NDST2 in HCC was evaluated using big data analysis. FOXP4 expression was detected in clinical samples of HCC. The gene expression levels in an in vitro heat-stressed HCC cell model were determined using quantitative real-time PCR (RT-qPCR) and Western blotting. The effects of the genes on heat-stressed HCC cells were investigated using Cell Counting Kit-8 (CCK-8), scratch, Transwell migration, and invasion assays. Additionally, the regulatory relationship between FOXP4 and NDST2 was validated using the Cleavage Under Targets and Tagmentation (CUT&Tag) experiments and phenotypic assays.

Results

High FOXP4 expression was correlated with liver cancer occurrence and development. In the heat-stressed HCC cell model, downregulating FOXP4 inhibited cancer cell progression. Besides, there was a positive association between FOXP4 and NDST2 in liver cancer. Suppressing FOXP4 reduced NDST2 expression in the heat-stressed HCC cells. Furthermore, reducing NDST2 expression weakened the biological behavior of heat-stressed HCC cells.

Conclusion

FOXP4 and NDST2 are crucial in the incomplete thermal ablation of residual cancer. FOXP4 might regulate the biological progression of residual HCC after incomplete thermal ablation through NDST2.

Drug resistance and tumor immune microenvironment: An overview of current understandings (Review)

The use of antitumor drugs represents a reliable strategy for cancer therapy. Unfortunately, drug resistance has become increasingly common and contributes to tumor metastasis and local recurrence. The tumor immune microenvironment (TME) consists of immune cells, cytokines and immunomodulators, and collectively they influence the response to treatment. Epigenetic changes including DNA methylation and histone modification, as well as increased drug exportation have been reported to contribute to the development of drug resistance in cancers. In the past few years, the majority of studies on tumors have only focused on the development and progression of a tumor from a mechanistic standpoint; few studies have examined whether the changes in the TME can also affect tumor growth and drug resistance. Recently, emerging evidence have raised more concerns regarding the role of TME in the development of drug resistance. In the present review, it was discussed how the suppressive TME adapts to drug resistance characterized by the cooperation of immune cells, cytokines, immunomodulators, stromal cells and extracellular matrix. Furthermore, it was reviewed how these immunological or metabolic changes alter immuno‑surveillance and thus facilitate tumor drug resistance. In addition, potential targets present in the TME for developing novel therapeutic strategies to improve individualized therapy for cancer treatment were revealed.

Barley polysaccharides inhibit colorectal cancer by two relatively independent pathways

Colorectal cancer is one of the most common types of cancer worldwide that can lead to serious injury and death. Although polysaccharides are widely recognized as having antitumor activity, there has been little research on the role of barley polysaccharides (BP)1 in colorectal cancer. The results of our research suggest that BP (300 mg/kg) had a significant inhibitory effect on colorectal cancer, and this effect was achieved through two pathways. First, BP can directly promote the secretion of protective metabolites like 5-(4-Hydroxyphenyl)-5-phenylimidazolidine-2,4-dione and 2,3-Bis(4-hydroxyphenyl)propionitrile thereby inhibiting the cancer pathways such as ERK, PI3K, WNT, JAK-STAT, Calcium, and Cell cycle cancer pathways to alleviate inflammation. Second, BP also can enrich beneficial intestinal bacteria such as Colidextribacter, Bilophila, and UCG-003 improve the intestinal barrier, promote the production of beneficial metabolites such as 5,8-Epoxy-5,8-dihydro-3-hydroxy-8'-apo-b,y-carotenal and L-Glutamic acid, and thus inhibit cancer pathways such as ERK, PI3K, Nuclear receptor, Cell cycle, Apoptosis and TGF-β. In conclusion, our findings suggest for the first time that BP can alleviate colorectal cancer by two relatively independent pathways: direct action and indirect action via the gut microbiota on both colon tumor cells and microbiota.