Potentiating the antitumour response of CD8(+) T cells by modulating cholesterol metabolism. Nature. 2016;531:651-655. [PMID: 26982734 DOI: 10.1038/nature17412]

Discovery of selective ACAT2 antagonist via a combination strategy based on deep docking, pharmacophore modelling, and molecular dynamics simulation

Acyl-CoA: cholesterol acyltransferase (ACAT), a pivotal enzyme in the absorption and metabolism of cholesterol, is primarily responsible for intracellular esterification. ACAT inhibition is expected to diminish plasma lipid levels by impeding intestinal cholesterol absorption, thereby preventing the progression of atherosclerotic lesions. A previous study shows that selective inhibition of ACAT2 significantly mitigated hypercholesterolaemia and atherosclerosis in mouse models. Therefore, the need for ACAT2 selective inhibitors becomes particularly urgent. In this study, we established a multilayer virtual screening workflow and subjected biologically evaluated representative compounds to enzyme inhibitory assays. The experimental results indicated that the two compounds, STL565001 (inhibition rate at 25 μM: 75.7 ± 27.8%, selectivity = 6) and STL528213 (inhibition rate at 25 μM: 87.8 ± 12.4%, selectivity = 13), demonstrated robust activity against ACAT2, displaying greater selectivity for ACAT2 than for ACAT1. The molecular mechanisms governing the inhibitory activities of the selected compounds were systematically elucidated using computational approaches. In addition, hotspot residues in ACAT2 that are crucial for ligand binding were successfully identified. In summary, we devised a multilayer screening scheme to expeditiously and efficiently identify compounds with enzyme inhibitory activity, offering novel scaffolds for subsequent drug design centred on ACAT2 targets.

Intersecting Blood Cytokines With Cholesterol Parameters to Profile Patients With Advanced Solid Tumors Receiving Immune Checkpoint Inhibitors

The study investigated the relationship between serum proinflammatory cytokine levels, cholesterol metabolism, and clinical outcome in cancer patients undergoing immune checkpoint inhibitors (ICIs). Peripheral blood was collected before therapy from ICI-treated advanced cancer patients. We retrospectively assessed plasma total cholesterol (TC), ABCA1- and ABCG1-mediated cholesterol efflux (CE), passive diffusion (PD), cholesterol loading capacity (CLC), and serum IL-6, IL-10, and TNF-α. The association between blood cholesterol parameters and inflammatory cytokines and their effect on overall survival (OS), progression-free survival (PFS), and clinical benefit (CB) from ICIs were statistically assessed. Among 70 consecutively enrolled patients (nonsmall cell lung cancer: 94%; renal cell carcinoma: 6%), TC, CLC, and cholesterol PD resulted significantly higher in IL-6 low and IL-10 low cases ( P <0.05), whereas ABCA1-mediated CE was increased in IL-10 high patients ( P =0.018). Uni- and multivariable analysis revealed meaningfully longer OS and PFS in IL-6 low (HR 2.13 and 2.97, respectively) and IL-10 low (HR 3.17 and 2.62) groups. At univariate analysis all cholesterol-related indices significantly correlated with OS and PFS, whereas at multivariate only high PD was validated as a protection factor (OS, HR 0.75; PFS, HR 0.84). Finally, uni- and multivariable showed a statistically significant inverse association of CB with ABCG1-CE (OR 0.62), as with IL-6 (OR 0.13) and IL-10 (OR 0.10). In-depth characterization of the interplay between blood cholesterol metabolism and immune-inflammatory cytokines might provide novel insights into the complex relationship among cancer, inflammation, lipids profile, and response to immunotherapy.

Regulation of CD8+ T cells by lipid metabolism in cancer progression

Dysregulation of lipid metabolism is a key characteristic of the tumor microenvironment, where tumor cells utilize lipids for proliferation, survival, metastasis, and evasion of immune surveillance. Lipid metabolism has become a critical regulator of CD8+ T-cell-mediated antitumor immunity, with excess lipids in the tumor microenvironment impeding CD8+ T-cell activities. Considering the limited efficacy of immunotherapy in many solid tumors, targeting lipid metabolism to enhance CD8+ T-cell effector functions could significantly improve immunotherapy outcomes. In this review, we examine recent findings on how lipid metabolic processes, including lipid uptake, synthesis, and oxidation, regulate CD8+ T cells within tumors. We also assessed the impact of different lipids on CD8+ T-cell-mediated antitumor immunity, with a particular focus on how lipid metabolism affects mitochondrial function in tumor-infiltrating CD8+ T cells. Furthermore, as cancer is a systemic disease, we examined systemic factors linking lipid metabolism to CD8+ T-cell effector function. Finally, we summarize current therapeutic approaches that target lipid metabolism to increase antitumor immunity and enhance immunotherapy. Understanding the molecular and functional interplay between lipid metabolism and CD8+ T cells offers promising therapeutic opportunities for cancer treatment.

Farnesyl pyrophosphate potentiates dendritic cell migration in autoimmunity through mitochondrial remodelling

Cellular metabolism modulates dendritic cell (DC) maturation and activation. Migratory dendritic cells (mig-DCs) travelling from the tissues to draining lymph nodes (dLNs) are critical for instructing adaptive immune responses. However, how lipid metabolites influence mig-DCs in autoimmunity remains elusive. Here, we demonstrate that farnesyl pyrophosphate (FPP), an intermediate of the mevalonate pathway, accumulates in mig-DCs derived from mice with systemic lupus erythematosus (SLE). FPP promotes mig-DC survival and germinal centre responses in the dLNs by coordinating protein geranylgeranylation and mitochondrial remodelling. Mechanistically, FPP-dependent RhoA geranylgeranylation promotes mitochondrial fusion and oxidative respiration through mitochondrial RhoA-MFN interaction, which subsequently facilitates the resolution of endoplasmic reticulum stress in mig-DCs. Simvastatin, a chemical inhibitor of the mevalonate pathway, restores mitochondrial function in mig-DCs and ameliorates systemic pathogenesis in SLE mice. Our study reveals a critical role for FPP in dictating mig-DC survival by reprogramming mitochondrial structure and metabolism, providing new insights into the pathogenesis of DC-dependent autoimmune diseases.

The impact of acyl-CoA:cholesterol transferase (ACAT) inhibitors on biophysical membrane properties depends on membrane lipid composition

Acyl-coenzyme A: cholesterol acyltransferases are enzymes which are involved in the homeostasis of cholesterol. Impaired enzyme activity is associated with the occurrence of various diseases like Alzheimer's disease, atherosclerosis, and cancers. At present, mitotane is the only inhibitor of this class of enzymes in clinical use for the treatment of adrenocortical carcinoma but associated with common and severe adverse effects. The therapeutic effect of mitotane depends on its interaction with cellular membranes. The search for less toxic but equally effective compounds is hampered by an incomplete understanding of these biophysical properties. In the present study, the interaction of the three ACAT inhibitors nevanimibe, Sandoz 58-035, and AZD 3988 with membranes has been investigated using lipid model membranes in conjunction with biophysical experimental (NMR, ESR, fluorescence) and theoretical (MD simulations) approaches. The data show, that the drugs (i) incorporate into lipid membranes, (ii) differently influence the structure of lipid membranes; (iii) affect membrane structure depending on the lipid composition; and (iv) do not cause hemolysis of red blood cells. The results are discussed with regard to the use of the drugs, in particular to better understand their efficacy and possible side effects.

The missing link between cancer stem cells and immunotherapy

Cancer stem cells (CSCs) are cancer cells that can self-renew and give rise to tumors. The multipotency of CSCs enables the generation of diverse cancer cell types and their potential for differentiation and resilience against chemotherapy and radiation. Additionally, specific biomarkers have been identified for them, such as CD24, CD34, CD44, CD47, CD90, and CD133. The CSC model suggests that a subset of CSCs within tumors is responsible for tumor growth. The tumor microenvironment (TME), including fibroblasts, immune cells, adipocytes, endothelial cells, neuroendocrine (NE) cells, extracellular matrix (ECM), and extracellular vesicles, has a part in shielding CSCs from the host immune response as well as protecting them against anticancer drugs. The regulation of cancer stem cell plasticity by cancer-associated fibroblasts (CAFs) occurs through specific signaling pathways that differ among various types of cancer, utilizing the IGF-II/IGF1R, FAK, and c-Met/FRA1/HEY1 signaling pathways. Due to the intricate dynamics of CSC proliferation, controlling their growth necessitates innovative approaches and much more research. Our current review speculates an outline of how the TME safeguards stem cells, their interaction with CSCs, and the involvement of the immune and inflammatory systems in CSC differentiation and maintenance. Several technologies have the ability to identify CSCs; however, each approach has limitations. We discuss how these methods can aid in recognizing CSCs in several cancer types, comprising brain, breast, liver, stomach, and colon cancer. Furthermore, we explore different immunotherapeutic strategies targeting CSCs, including stimulating cancer-specific T cells, modifying immunosuppressive TMEs, and antibody-mediated therapy targeting CSC markers.

Prognostic value of three clinical nutrition scoring system (NRI, PNI, and CONUT) in elderly patients with prostate cancer

Background

Most of patients with prostate cancer (PCa) are elderly and have a long course of disease. Preoperative assessment of the patient's clinical nutritional status facilitates early intervention and improves patient prognosis.

Methods

We assessed the nutritional status of PCa patients utilizing the Nutritional Risk Index (NRI), Prognostic Nutritional Index (PNI), and Controlling Nutritional Status (CONUT) scoring systems. Survival comparisons between groups were conducted using Kaplan-Meier curve analysis and log-rank tests, while Cox proportional hazards regression analysis was employed to identify independent prognostic factors. Furthermore, we implemented bootstrap-based optimism correction methods to validate the scoring systems and applied decision curve analysis to evaluate the non-inferiority of these three clinical nutrition scoring systems relative to the conventional American Joint Committee on Cancer (AJCC) staging.

Results

In this study, malnutrition was diagnosed in 31.51% of the patients using the NRI, 13.02% using the PNI, and 88.28% using the CONUT score. After adjusting for confounders, normal nutritional status as defined by NRI and PNI emerged as an independent prognostic factor for prostate-specific antigen progression-free survival (PSA-PFS). However, nutritional status assessed by CONUT inaccurately predicted PSA-PFS. Normal nutritional status, as determined by all three scoring systems, was found to be an independent prognostic factor for progression-free survival (PFS). Following adjustments for optimistic estimates, the C-index for NRI in predicting both PSA-PFS and PFS remained the highest among the three scoring systems. The results of the DCA indicated that the C-index of all three scoring systems was higher than that of AJCC stage.

Conclusions

NRI, PNI, and CONUT are convenient and clinically applicable scoring systems. A clinical malnutrition intervention may improve the prognosis of prostate cancer patients.

Cholesterol inhibition enhances antitumor response of gilteritinib in lung cancer cells

Repositioning approved antitumor drugs for different cancers is a cost-effective approach. Gilteritinib was FDA-approved for the treatment of FLT3-mutated acute myeloid leukemia in 2018. However, the therapeutic effects and mechanism of Gilteritinib on other malignancies remain to be defined. In this study, we identified that gilteritinib has an inhibitory effect on lung cancer cells (LCCs) without FLT3 mutation in vitro and in vivo. Unexpectedly, we found that gilteritinib induces cholesterol accumulation in LCCs via upregulating cholesterol biosynthetic genes and inhibiting cholesterol efflux. This gilteritinib-induced cholesterol accumulation not only attenuates the antitumor effect of gilteritinib but also induces gilteritinib-resistance in LCCs. However, when cholesterol synthesis was prevented by squalene epoxidase (SQLE) inhibitor NB-598, both LCCs and gilteritinib-resistant LCCs became sensitive to gilteritinib. More importantly, the natural cholesterol inhibitor 25-hydroxycholesterol (25HC) can suppress cholesterol biosynthesis and increase cholesterol efflux in LCCs. Consequently, 25HC treatment significantly increases the cytotoxicity of gilteritinib on LCCs, which can be rescued by the addition of exogenous cholesterol. In a xenograft model, the combination of gilteritinib and 25HC showed significantly better efficacy than either monotherapy in suppressing lung cancer growth, without obvious general toxicity. Thus, our findings identify an increase in cholesterol induced by gilteritinib as a mechanism for LCC survival, and highlight the potential of combining gilteritinib with cholesterol-lowering drugs to treat lung cancer.

Lipids in the tumor microenvironment: immune modulation and metastasis

Tumor cells can undergo metabolic adaptations that support their growth, invasion, and metastasis, such as reprogramming lipid metabolism to meet their energy demands and to promote survival in harsh microenvironmental conditions, including hypoxia and acidification. Metabolic rewiring, and especially alterations in lipid metabolism, not only fuel tumor progression but also influence immune cell behavior within the tumor microenvironment (TME), leading to immunosuppression and immune evasion. These processes, in turn, may contribute to the metastatic spread of cancer. The diverse metabolic profiles of immune cell subsets, driven by the TME and tumor-derived signals, contribute to the complex immune landscape in tumors, affecting immune cell activation, differentiation, and effector functions. Understanding and targeting metabolic heterogeneity among immune cell subsets will be crucial for developing effective cancer immunotherapies that can overcome immune evasion mechanisms and enhance antitumor immunity.

Inhibition of PCSK9: A Promising Enhancer for Anti-PD-1/PD-L1 Immunotherapy

Immune checkpoint therapy, such as programmed cell death protein 1/programmed death-ligand 1 (PD-1/PD-L1) blockade, has achieved remarkable results in treating various tumors. However, most cancer patients show a low response rate to PD-1/PD-L1 blockade, especially those with microsatellite stable/mismatch repair-proficient colorectal cancer subtypes, which indicates an urgent need for new approaches to augment the efficacy of PD-1/PD-L1 blockade. Cholesterol metabolism, which involves generating multifunctional metabolites and essential membrane components, is also instrumental in tumor development. In recent years, inhibiting proprotein convertase subtilisin/kexin type 9 (PCSK9), a serine proteinase that regulates cholesterol metabolism, has been demonstrated to be a method enhancing the antitumor effect of PD-1/PD-L1 blockade to some extent. Mechanistically, PCSK9 inhibition can maintain the recycling of major histocompatibility protein class I, promote low-density lipoprotein receptor-mediated T-cell receptor recycling and signaling, and modulate the tumor microenvironment (TME) by affecting the infiltration and exclusion of immune cells. These mechanisms increase the quantity and enhance the antineoplastic effect of cytotoxic T lymphocyte, the main functional immune cells involved in anti-PD-1/PD-L1 immunotherapy, in the TME. Therefore, combining PCSK9 inhibition therapy with anti-PD-1/PD-L1 immunotherapy may provide a novel option for improving antitumor effects and may constitute a promising research direction. This review concentrates on the relationship between PCSK9 and cholesterol metabolism, systematically discusses how PCSK9 inhibition potentiates PD-1/PD-L1 blockade for cancer treatment, and highlights the research directions in this field.

Exploring the impact of HDL and LMNA gene expression on immunotherapy outcomes in NSCLC: a comprehensive analysis using clinical & gene data

Objectives

Analyzing the impact of peripheral lipid levels on the efficacy of immune checkpoint inhibitor therapy in non-small cell lung cancer (NSCLC) patient populations and exploring whether it can serve as a biomarker for broadening precise selection of individuals benefiting from immunotherapy.

Methods

We retrospectively collected clinical data from 201 cases of NSCLC patients receiving immune checkpoint inhibitor therapy. The clinical information included biochemical indicators like total cholesterol, triglycerides, high-density lipoprotein (HDL), and low-density lipoprotein (LDL). We utilized machine learning algorithms and Cox proportional hazards regression models to investigate independent predictors for both short-term and long-term efficacy of immunotherapy. Additionally, we concurrently developed a survival prediction model. Analyzing the Genes of Patients with Treatment Differences to Uncover Mechanisms.

Results

Correlation analysis revealed a significant positive association between HDL and ORR, DCR, and PFS. T-test results indicated that the high-HDL group exhibited higher DCR (81.97% vs. 45.57%) and ORR (61.48% vs. 16.46%). Kruskal-Wallis test showed that the high-HDL group had a longer median PFS (11 months vs. 6 months). Utilizing six machine learning algorithms, we constructed models to predict disease relief and stability. The model built using the random forest algorithm demonstrated superior performance, with AUC values of 0.858 and 0.802. Furthermore, both univariate and multivariate Cox analyses identified HDL and LDL as independent risk factors for predicting PFS. In patients with poor immunotherapy response, there is upregulation of BCL2L11, AKT1, and LMNA expression.

Conclusion

HDL and LDL are independent factors influencing the survival prognosis of NSCLC patients undergoing immune checkpoint inhibitor therapy. HDL is expected to become new biomarkers for predicting the immunotherapy efficacy in patients with NSCLC. In patients with poor immunotherapy response, upregulation of the LMNA gene leads to apoptosis resistance and abnormal lipid metabolism.

The role of cholesterol metabolism in lung cancer

Elevated serum cholesterol metabolism is associated with a reduced risk of lung cancer. Disrupted cholesterol metabolism is evident in both lung cancer patients and tumor cells. Inhibiting tumor cell cholesterol uptake or biosynthesis pathways, through the modulation of receptors and enzymes such as liver X receptor and sterol-regulatory element binding protein 2, effectively restrains lung tumor growth. Similarly, promoting cholesterol excretion yields comparable effects. Cholesterol metabolites, including oxysterols and isoprenoids, play a crucial role in regulating cholesterol metabolism within tumor cells, consequently impacting cancer progression. In lung cancer patients, both the cholesterol levels in the tumor microenvironment and within tumor cells significantly influence cell growth, proliferation, and metastasis. The effects of cholesterol metabolism are further mediated by the reprogramming of immune cells such as T cells, B cells, macrophages, myeloid-derived suppressor cells, among others. Ongoing research is investigating drugs targeting cholesterol metabolism for clinical treatments. Statins, targeting the cholesterol biosynthesis pathway, are widely employed in lung cancer treatment, either as standalone agents or in combination with other drugs. Additionally, drugs focusing on cholesterol transportation have shown promise as effective therapies for lung cancer. In this review, we summarized current research regarding the rule of cholesterol metabolism and therapeutic advances in lung cancer.

Causal effects and metabolites mediators between immune cell and risk of colorectal cancer: a Mendelian randomization study

Objective

The involvement of immune cells in colorectal cancer (CRC) and their interplay with metabolic disorders are yet to be fully elucidated. This study examines how peripheral immune cells, inferred genetically, affect CRC and investigates the intermediary roles of metabolites.

Methods

We employed a two-sample bidirectional Mendelian randomization (MR) approach to assess the causal influence of immune cells on CRC. Additionally, a two-step MR strategy was utilized to pinpoint potential metabolites that mediate this effect. Our analysis incorporated data from genome-wide association studies (GWAS), involving 731 immune cell types, 1,400 metabolites, and CRC outcomes. The primary method of analysis was randomized inverse variance weighting (IVW), supported by MR-Egger, weighted median, simple mode, and weighted mode analyses. Sensitivity checks were conducted using Cochran's Q test, MR-PRESSO test, MR-Egger regression intercept, and leave-one-out analysis.

Results

The study identified 23 immune cell types and 17 metabolites that are causally linked to CRC. Our mediation analysis highlighted that nine metabolites act as intermediaries in the relationship between nine specific immune cells and CRC risk. Notably, The ratios of Adenosine 5'-monophosphate (AMP) to aspartate and Retinol (Vitamin A) to linoleoyl-arachidonoyl-glycerol (18:2 to 20:4) were found to concurrently mediate the promoting effects of Myeloid DC %DC and BAFF-R on B cells in colorectal cancer (CRC). Moreover, iminodiacetate (IDA) was found to mediate the protective effect of CD14+ CD16- monocytes on CRC, contributing 11.8% to this mediation. In contrast, IDA was also seen to decrease the protective effect of IgD+ CD38br %B cells on CRC risk, with a mediation effect proportion of -10.4%.

Conclusion

This study delineates a complex network involving immune cells, metabolites, and CRC, suggesting a multifaceted pathophysiological interaction. The identified causal links and mediation pathways underscore potential therapeutic targets, providing a foundation for interventions aimed at modulating immune responses to manage CRC.

PD-1 signaling limits expression of phospholipid phosphatase 1 and promotes intratumoral CD8+ T cell ferroptosis

The tumor microenvironment (TME) promotes metabolic reprogramming and dysfunction in immune cells. Here, we examined the impact of the TME on phospholipid metabolism in CD8+ T cells. In lung cancer, phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were lower in intratumoral CD8+ T cells than in circulating CD8+ T cells. Intratumoral CD8+ T cells exhibited decreased expression of phospholipid phosphatase 1 (PLPP1), which catalyzes PE and PC synthesis. T cell-specific deletion of Plpp1 impaired antitumor immunity and promoted T cell death by ferroptosis. Unsaturated fatty acids in the TME stimulated ferroptosis of Plpp1-/- CD8+ T cells. Mechanistically, programmed death-1 (PD-1) signaling in CD8+ T cells induced GATA1 binding to the promoter region Plpp1 and thereby suppressed Plpp1 expression. PD-1 blockade increased Plpp1 expression and restored CD8+ T cell antitumor function but did not rescue dysfunction of Plpp1-/- CD8+ T cells. Thus, PD-1 signaling regulates phospholipid metabolism in CD8+ T cells, with therapeutic implications for immunotherapy.

Metabolic reprogramming and immune evasion: the interplay in the tumor microenvironment

Tumor cells possess complex immune evasion mechanisms to evade immune system attacks, primarily through metabolic reprogramming, which significantly alters the tumor microenvironment (TME) to modulate immune cell functions. When a tumor is sufficiently immunogenic, it can activate cytotoxic T-cells to target and destroy it. However, tumors adapt by manipulating their metabolic pathways, particularly glucose, amino acid, and lipid metabolism, to create an immunosuppressive TME that promotes immune escape. These metabolic alterations impact the function and differentiation of non-tumor cells within the TME, such as inhibiting effector T-cell activity while expanding regulatory T-cells and myeloid-derived suppressor cells. Additionally, these changes lead to an imbalance in cytokine and chemokine secretion, further enhancing the immunosuppressive landscape. Emerging research is increasingly focusing on the regulatory roles of non-tumor cells within the TME, evaluating how their reprogrammed glucose, amino acid, and lipid metabolism influence their functional changes and ultimately aid in tumor immune evasion. Despite our incomplete understanding of the intricate metabolic interactions between tumor and non-tumor cells, the connection between these elements presents significant challenges for cancer immunotherapy. This review highlights the impact of altered glucose, amino acid, and lipid metabolism in the TME on the metabolism and function of non-tumor cells, providing new insights that could facilitate the development of novel cancer immunotherapies.

Reprogramming the immunosuppressive tumor microenvironment through nanomedicine: an immunometabolism perspective

Increasing evidence indicates that immunotherapy is hindered by a hostile tumor microenvironment (TME) featured with deprivation of critical nutrients and pooling of immunosuppressive metabolites. Tumor cells and immunosuppressive cells outcompete immune effector cells for essential nutrients. Meanwhile, a wide range of tumor cell-derived toxic metabolites exerts negative impacts on anti-tumor immune response, diminishing the efficacy of immunotherapy. Nanomedicine with excellent targetability offers a novel approach to improving cancer immunotherapy via metabolically reprogramming the immunosuppressive TME. Herein, we review recent strategies of enhancing immunotherapeutic effects through rewiring tumor metabolism via nanomedicine. Attention is drawn on immunometabolic tactics for immune cells and stromal cells in the TME via nanomedicine. Additionally, we discuss future directions of developing metabolism-regulating nanomedicine for precise and efficacious cancer immunotherapy.

Nanotechnology-Assisted CAR-T-Cell Therapy for Tumor Treatment

The adoptive transfer of T cells redirected by chimeric antigen receptors (CARs) has made a dramatic breakthrough in defeating hematological malignancies. However, in solid tumor treatment, CAR-T-cell therapy has attained limited therapeutic benefits due to insufficient infiltration and expansion, rapidly diminishing function following adoptive transfer, and severe life-threatening toxicities. To address these challenges, advancements in nanotechnology have utilized innovative approaches to devise stronger CAR-T cells with reduced toxicity and enhanced anti-tumor activity. Equipping CAR-T cells with multifunctional nanoparticles can abrogate immunosuppressive signaling in the tumor area, augment the functions of CAR-T cells, and mitigate their toxicity against normal tissues. Additionally, nanoparticle-mediated CAR-T-cell programming has the potential to optimize manufacturing and lower the cost for the broader implementation of CAR-T-cell therapy. In this review, we introduce the obstacles to be surmounted in CAR-T-cell therapy, highlight the nanotechnology-based strategies that aim to enrich the therapeutic applications of CAR-T-cell therapy, and envision the prospect of nanoparticle-assisted CAR-T-cell therapy.

Cobalt(III) prodrug-based nanomedicine for inducing immunogenic cell death and enhancing chemo-immunotherapy

Despite impressive advances in immune checkpoint blockade therapy, its efficacy as a standalone treatment remains limited. The influence of chemotherapeutic agents on tumor immunotherapy has progressively come to light in recent years, positioning them as promising contenders in the realm of combination therapy options for tumor immunotherapy. Herein, we present the rational design, synthesis, and biological evaluation of the first example of a Co(III) prodrug (Co2) capable of eliciting a localized cytotoxic effect while simultaneously inducing a systemic immune response via type II immunogenic cell death (ICD). To enhance its pharmacological properties, a glutathione-sensitive polymer was synthesized, and Co2 was encapsulated into polymeric nanoparticles (NP-Co2) to improve efficacy. Furthermore, NP-Co2 activates the GRP78/p-PERK/p-eIF2α/CHOP pathway, thereby inducing ICD in cancer cells. This facilitates the transformation of "cold tumors" into "hot tumors" and augments the effectiveness of the PD-1 monoclonal antibody (αPD-1). In essence, this nanomedicine, utilizing Co(III) prodrugs to induce ICD, provides a promising strategy to enhance chemotherapy and αPD-1 antibody-mediated cancer immunotherapy.

Metabolic reprogramming of the tumor microenvironment to enhance immunotherapy

Immunotherapy represents a promising treatment strategy for targeting various tumor types. However, the overall response rate is low due to the tumor microenvironment (TME). In the TME, numerous distinct factors actively induce immunosuppression, restricting the efficacy of anticancer immune reactions. Recently, metabolic reprogramming of tumors has been recognized for its role in modulating the tumor microenvironment to enhance immune cell responses in the TME. Furthermore, recent elucidations underscore the critical role of metabolic limitations imposed by the tumor microenvironment on the effectiveness of antitumor immune cells, guiding the development of novel immunotherapeutic approaches. Hence, achieving a comprehensive understanding of the metabolic requirements of both cancer and immune cells within the TME is pivotal. This insight not only aids in acknowledging the current limitations of clinical practices but also significantly shapes the trajectory of future research endeavors in the domain of cancer immunotherapy. In addition, therapeutic interventions targeting metabolic limitations have exhibited promising potential as combinatory treatments across diverse cancer types. In this review, we first discuss the metabolic barriers in the TME. Second, we explore how the immune response is regulated by metabolites. Finally, we will review the current strategy for targeting metabolism to not simply inhibit tumor growth but also enhance antitumor immune responses. Thus, we could suggest potent combination therapy for improving immunotherapy with metabolic inhibitors. [BMB Reports 2024; 57(9): 388-399].

PPARβ/δ-orchestrated metabolic reprogramming supports the formation and maintenance of memory CD8+ T cells

The formation of memory T cells is a fundamental feature of adaptative immunity, allowing the establishment of long-term protection against pathogens. Although emerging evidence suggests that metabolic reprogramming is crucial for memory T cell differentiation and survival, the underlying mechanisms that drive metabolic rewiring in memory T cells remain unclear. Here, we found that up-regulation of the nuclear receptor peroxisome proliferator-activated receptor β/δ (PPARβ/δ) instructs the metabolic reprogramming that occurs during the establishment of central memory CD8+ T cells. PPARβ/δ-regulated changes included suppression of aerobic glycolysis and enhancement of oxidative metabolism and fatty acid oxidation. Mechanistically, exposure to interleukin-15 and expression of T cell factor 1 facilitated activation of the PPARβ/δ pathway, counteracting apoptosis induced by antigen clearance and metabolic stress. Together, our findings indicate that PPARβ/δ is a master metabolic regulator orchestrating a metabolic switch that may be favorable for T cell longevity.

Research progress of SREBP and its role in the pathogenesis of autoimmune rheumatic diseases

Autoimmune rheumatic diseases comprise a group of immune-related disorders characterized by non-organ-specific inflammation. These diseases include systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), ankylosing spondylitis (AS), gout, among others. Typically involving the hematologic system, these diseases may also affect multiple organs and systems. The pathogenesis of autoimmune rheumatic immune diseases is complex, with diverse etiologies, all associated with immune dysfunction. The current treatment options for this type of disease are relatively limited and come with certain side effects. Therefore, the urgent challenge remains to identify novel therapeutic targets for these diseases. Sterol regulatory element-binding proteins (SREBPs) are basic helix-loop-helix-leucine zipper transcription factors that regulate the expression of genes involved in lipid and cholesterol biosynthesis. The expression and transcriptional activity of SREBPs can be modulated by extracellular stimuli such as polyunsaturated fatty acids, amino acids, glucose, and energy pathways including AKT-mTORC and AMP-activated protein kinase (AMPK). Studies have shown that SREBPs play roles in regulating lipid metabolism, cytokine production, inflammation, and the proliferation of germinal center B (GCB) cells. These functions are significant in the pathogenesis of rheumatic and immune diseases (Graphical abstract). Therefore, this paper reviews the potential mechanisms of SREBPs in the development of SLE, RA, and gout, based on an exploration of their functions.

Multifunctional Nanomaterials Mediate Cholesterol Depletion for Cancer Treatment

Cholesterol is an essential membrane component, and the metabolites from cholesterol play important biological functions to intricately support cancer progression and dampen immune responses. Preclinical and clinical studies have demonstrated the role of cholesterol metabolism regulation on inhibiting tumor growth, remodeling the immunosuppressive tumor microenvironment (TME), and enhancing anti-tumor immunity. In this minireview, we discuss complex cholesterol metabolism in tumors, its important role in cancer progression, and its influences on immune cells in the TME. We provide an overview of recent advances in cancer treatment through regulating cholesterol metabolism. We discuss the design of cholesterol-altering multifunctional nanomaterials to regulate oxidative stress, modulate immune checkpoints, manipulate mechanical stress responses, and alter cholesterol metabolic pathways. Additionally, we examine the interactions between cholesterol metabolism regulation and established cancer treatments with the aim of identifying efficient strategies to disrupt cholesterol metabolism and synergistic combination therapies for effective cancer treatment.

Hematological indicator-based machine learning models for preoperative prediction of lymph node metastasis in cervical cancer

Background

Lymph node metastasis (LNM) is an important prognostic factor for cervical cancer (CC) and determines the treatment strategy. Hematological indicators have been reported as being useful biomarkers for the prognosis of a variety of cancers. This study aimed to evaluate the feasibility of machine learning models characterized by preoperative hematological indicators to predict the LNM status of CC patients before surgery.

Methods

The clinical data of 236 patients with pathologically confirmed CC were retrospectively analyzed at the Gynecology Oncology Department of the First Affiliated Hospital of Bengbu Medical University from November 2020 to August 2022. The least absolute shrinkage and selection operator (LASSO) was used to select 21 features from 35 hematological indicators and for the construction of 6 machine learning predictive models, including Adaptive Boosting (AdaBoost), Gaussian Naive Bayes (GNB), and Logistic Regression (LR), as well as Random Forest (RF), Support Vector Machines (SVM), and Extreme Gradient Boosting (XGBoost). Evaluation metrics of predictive models included the area under the receiver operating characteristic curve (AUC), accuracy, specificity, sensitivity, and F1-score.

Results

RF has the best overall predictive performance for ten-fold cross-validation in the training set. The specific performance indicators of RF were AUC (0.910, 95% confidence interval [CI]: 0.820-1.000), accuracy (0.831, 95% CI: 0.702-0.960), specificity (0.835, 95% CI: 0.708-0.962), sensitivity (0.831, 95% CI: 0.702-0.960), and F1-score (0.829, 95% CI: 0.696-0.962). RF had the highest AUC in the testing set (AUC = 0.854).

Conclusion

RF based on preoperative hematological indicators that are easily available in clinical practice showed superior performance in the preoperative prediction of CC LNM. However, investigations on larger external cohorts of patients are required for further validation of our findings.

Metabolic reprogramming in tumor immune microenvironment: Impact on immune cell function and therapeutic implications

Understanding of the metabolic reprogramming has revolutionized our insights into tumor progression and potential treatment. This review concentrates on the aberrant metabolic pathways in cancer cells within the tumor microenvironment (TME). Cancer cells differ from normal cells in their metabolic processing of glucose, amino acids, and lipids in order to adapt to heightened biosynthetic and energy needs. These metabolic shifts, which crucially alter lactic acid, amino acid and lipid metabolism, affect not only tumor cell proliferation but also TME dynamics. This review also explores the reprogramming of various immune cells in the TME. From a therapeutic standpoint, targeting these metabolic alterations represents a novel cancer treatment strategy. This review also discusses approaches targeting the regulation of metabolism of different nutrients in tumor cells and influencing the tumor microenvironment to enhance the immune response. In summary, this review summarizes metabolic reprogramming in cancer and its potential as a target for innovative therapeutic strategies, offering fresh perspectives on cancer treatment.

NR0B2 re-educates myeloid immune cells to reduce regulatory T cell expansion and progression of breast and other solid tumors

Although survival from breast cancer has dramatically increased, many will develop recurrent, metastatic disease. Unfortunately, survival for this stage of disease remains very low. Activating the immune system has incredible promise since it has the potential to be curative. However, immune checkpoint blockade (ICB) which works through T cells has been largely disappointing for metastatic breast cancer. One reason for this is a suppressive myeloid immune compartment that is unaffected by ICB. Cholesterol metabolism and proteins involved in cholesterol homeostasis play important regulatory roles in myeloid cells. Here, we demonstrate that NR0B2, a nuclear receptor involved in negative feedback of cholesterol metabolism, works in several myeloid cell types to impair subsequent expansion of regulatory T cells (Tregs); Tregs being a subset known to be highly immune suppressive and associated with poor therapeutic response. Within myeloid cells, NR0B2 serves to decrease many aspects of the inflammasome, ultimately resulting in decreased IL1β; IL1β driving Treg expansion. Importantly, mice lacking NR0B2 exhibit accelerated tumor growth. Thus, NR0B2 represents an important node in myeloid cells dictating ensuing Treg expansion and tumor growth, thereby representing a novel therapeutic target to re-educate these cells, having impact across different solid tumor types. Indeed, a paper co-published in this issue demonstrates the therapeutic utility of targeting NR0B2.

Chain Extension of Piperazine in Ethanol: Synthesis of 2-(4-(2-(Phenylthio)ethyl)piperazinyl)acetonitriles and ACAT-1 Inhibitors

A base-induced synthesis of 2-(4-(2-(phenylthio)ethyl)piperazinyl) acetonitriles by reaction of disulfides, 1-(chloromethyl)-4-aza-1-azonia bicyclo[2.2.2]octane chloride and trimethylsilyl cyanide is reported. The scope of the method is demonstrated with 30 examples. The reaction mechanism research indicates that the three-component reaction would be a SN2 reaction. The products exhibit good activities towards advanced synthesis of aqueous soluble acyl-CoA: cholesterol O-acyltransferase-1 (ACAT-1) inhibitors. Our work is superior as it uses less-odor disulfides as carbon sources and EtOH as solvent in a water and dioxygen insensitive reaction system, followed by a simple purification process.

Low Serum Apolipoprotein A1 Levels Impair Antitumor Immunity of CD8+ T Cells via the HIF-1α-Glycolysis Pathway

An immunosuppressive microenvironment promotes the occurrence and development of tumors. Low apolipoprotein A1 (ApoA1) is closely related to tumor development, but the underlying mechanisms are unclear. This study investigated the association between serum ApoA1 levels and the immune microenvironment in endometrial, ovarian, and lung cancers. The serum ApoA1 level was decreased significantly in patients with endometrial and ovarian cancers compared with healthy controls. In endometrial cancer (EC) tissues, the low serum ApoA1 level group showed increased CD163+ macrophage infiltration and decreased CD8+ T-cell infiltration compared with the normal serum ApoA1 group. Compromised tumor-infiltrating CD8+ T-cell functions and decreased CD8+ T-cell infiltration also were found in tumor-bearing Apo1-knockout mice. CD8+ T-cell depletion experiments confirmed that ApoA1 exerted its antitumor activity in a CD8+ T-cell-dependent manner. In vitro experiments showed that the ApoA1 mimetic peptide L-4F directly potentiated the antitumor activity of CD8+ T cells via a HIF-1α-mediated glycolysis pathway. Mechanistically, ApoA1 suppressed ubiquitin-mediated degradation of HIF-1α protein by downregulating HIF-1α subunit α inhibitor. This regulatory process maintained the stability of HIF-1α protein and activated the HIF-1α signaling pathway. Tumor-bearing Apoa1 transgenic mice showed an increased response to anti-PD-1 therapy, leading to reduced tumor growth along with increased infiltration of activated CD8+ T cells and enhanced tumor necrosis. The data reported herein demonstrate critical roles for ApoA1 in enhancing CD8+ T-cell immune functions via HIF-1α-mediated glycolysis and support clinical investigation of combining ApoA1 supplementation with anti-PD-1 therapy for treating cancer.

The immunosuppressive landscape in tumor microenvironment

Recent advances in cancer immunotherapy, especially immune checkpoint inhibitors (ICIs), have revolutionized the clinical outcome of many cancer patients. Despite the fact that impressive progress has been made in recent decades, the response rate remains unsatisfactory, and many patients do not benefit from ICIs. Herein, we summarized advanced studies and the latest insights on immune inhibitory factors in the tumor microenvironment. Our in-depth discussion and updated landscape of tumor immunosuppressive microenvironment may provide new strategies for reversing tumor immune evasion, enhancing the efficacy of ICIs therapy, and ultimately achieving a better clinical outcome.

Association between thyroid hormone resistance and obesity: a cross-sectional study and mouse stimulation test

OBJECTIVE

Thyroid hormone influences key metabolic pathways, and reduced sensitivity to thyroid hormone is considered a new risk factor for adverse metabolic outcomes. However, the association between thyroid hormone resistance and obesity in euthyroid individuals is still unknown.

METHODS

We enrolled 8021 euthyroid individuals, calculated thyroid hormone resistance indices, and analyzed the association between thyroid hormone resistance and obesity by regression analysis. Furthermore, we conducted the thyrotropin-releasing hormone stimulation test in both control and obese mice (n = 5) to demonstrate the association.

RESULTS

The euthyroid adults with overweight and obesity had increased thyroid hormone resistance indices (all p < 0.05). BMI and prevalence of overweight and obesity increased (odds ratio of thyroid feedback quantile-based index [ORTFQI] = 1.164, p = 0.036; OR of free triiodothyronine/free thyroxine [ORFT3/FT4] = 1.508, p < 0.001) following the elevation of thyroid hormone resistance indices. Mediation analysis indicated a complete mediation effect (beta coefficient of indirect effect [βInd]= 6.838, p < 0.001) of metabolic disorders in the relationship. Furthermore, in the mice with obesity, the thyrotropin response to thyrotropin-releasing hormone stimulation (68.33-90.89 pg/mL) was comparatively blunted (p = 0.029).

CONCLUSIONS

Euthyroid individuals with obesity exhibit both central and peripheral thyroid hormone resistance, a phenomenon that is more pronounced in individuals with metabolic abnormalities. Thyroid hormone resistance is associated with an increased prevalence of overweight and obesity mediated by metabolic disorders.

A Bibliometric Analysis of Metabolic Reprogramming in the Tumor Microenvironment From 2003 to 2022

BACKGROUND

Despite considerable progress in cancer immunotherapy, it is not available for many patients. Resistance to immune checkpoint blockers arises from the intricate interactions between cancer and its microenvironment. Metabolic reprogramming in tumor and immune cells in the tumor microenvironment (TME) influences anti-tumor immune responses by remodeling the immune microenvironment. Metabolic reprogramming has emerged as an important hallmark of tumorigenesis. However, few studies have focused on the TME and metabolic reprogramming. Therefore, we aimed to explore the current research status and popular topics in TME-related metabolic reprogramming over a 20 years using a bibliometric approach.

METHODS

Studies focusing on metabolic reprogramming and TME were searched using the Web of Science Core Collection database. Bibliometric and visual analyses of the articles and reviews were performed using Bibliometrix, VOSviewer, and CiteSpace.

RESULTS

In total, 4726 articles published between 2003 and 2022 were selected. The number of publications and citations has increased annually. Cooperation network analysis indicated that the United States holds the foremost position in metabolic reprogramming and TME research with the highest volume of publications and citations, thus exerting the greatest influence. Among these institutions, Fudan University displayed the highest level of productivity. Frontiers in Immunology showed the highest degree of productivity in this field. Ho Ping-Chih made the most article contributions, and Pearce Edward J. was the most co-cited author. Four clusters were obtained after a cluster analysis of the authors' keywords: TME, metabolic reprogramming, immunometabolism, and immunity. Immunometabolism, glycolysis, immune cells, and tumor-associated macrophages are relatively recent keywords that have attracted increasing attention.

CONCLUSIONS

A comprehensive landscape of advancements in metabolic reprogramming and the TME was evaluated, which provided crucial information for scholars to further advance this promising field. Further research should explore new topics related to immunometabolism in the TME using a transdisciplinary approach.

Lck Function and Modulation: Immune Cytotoxic Response and Tumor Treatment More Than a Simple Event

Lck, a member of the Src kinase family, is a non-receptor tyrosine kinase involved in immune cell activation, antigen recognition, tumor growth, and cytotoxic response. The enzyme has usually been linked to T lymphocyte activation upon antigen recognition. Lck activation is central to CD4, CD8, and NK activation. However, recently, it has become clearer that activating the enzyme in CD8 cells can be independent of antigen presentation and enhance the cytotoxic response. The role of Lck in NK cytotoxic function has been controversial in a similar fashion as the role of the enzyme in CAR T cells. Inhibiting tyrosine kinases has been a highly successful approach to treating hematologic malignancies. The inhibitors may be useful in treating other tumor types, and they may be useful to prevent cell exhaustion. New, more selective inhibitors have been documented, and they have shown interesting activities not only in tumor growth but in the treatment of autoimmune diseases, asthma, and graft vs. host disease. Drug repurposing and bioinformatics can aid in solving several unsolved issues about the role of Lck in cancer. In summary, the role of Lck in immune response and tumor growth is not a simple event and requires more research.

Inhibition of PCSK9 enhances the anti-hepatocellular carcinoma effects of TCR-T cells and anti-PD-1 immunotherapy

T cells play important roles in antitumor immunity. However, given that the hepatocellular carcinoma (HCC) tumor microenvironment confers resistance to T cell-based immunotherapies, novel strategies to boost T cell-mediated antitumor efficacy are urgently needed for the treatment of HCC. Here, we show that high proprotein convertase subtilisin/kexin type9 (PCSK9) expression was negatively associated with HCC patient's overall survival and markers of CD8+ T cells. Pharmacological inhibition of PCSK9 enhanced tumor-specific killing and downregulated PD-1 expression of AFP-specific TCR-T. Inhibition of PCSK9 significantly enhances the anti-HCC efficacy of TCR-T cells and anti-PD-1 immunotherapy in vivo. Moreover, PCSK9 inhibitor suppressed HCC growth dependent on CD8+ T cells. Mechanically, pharmacological inhibition of PCSK9 promoted low-density lipoprotein receptor (LDLR)-mediated activation of mTORC1 signaling in CD8+ T cells. LDLR deficiency was shown to impair cellular mTORC1 signaling and the anti-HCC function of CD8 T cells. On the basis of our findings in this study, we propose a potential metabolic intervention strategy that could be used to enhance the antitumor effects of immunotherapy for HCC.

The multifaceted role of PCSK9 in cancer pathogenesis, tumor immunity, and immunotherapy

Proprotein convertase subtilisin/kexin type 9 (PCSK9), a well-known regulator of cholesterol metabolism and cardiovascular diseases, has recently garnered attention for its emerging involvement in cancer biology. The multifunctional nature of PCSK9 extends beyond lipid regulation and encompasses a wide range of cellular processes that can influence cancer progression. Studies have revealed that PCSK9 can modulate signaling pathways, such as PI3K/Akt, MAPK, and Wnt/β-catenin, thereby influencing cellular proliferation, survival, and angiogenesis. Additionally, the interplay between PCSK9 and cholesterol homeostasis may impact membrane dynamics and cellular migration, further influencing tumor aggressiveness. The central role of the immune system in monitoring and controlling cancer is increasingly recognized. Recent research has demonstrated the ability of PCSK9 to modulate immune responses through interactions with immune cells and components of the tumor microenvironment. This includes effects on dendritic cell maturation, T cell activation, and cytokine production, suggesting a role in shaping antitumor immune responses. Moreover, the potential influence of PCSK9 on immune checkpoints such as PD1/PD-L1 lends an additional layer of complexity to its immunomodulatory functions. The growing interest in cancer immunotherapy has prompted exploration into the potential of targeting PCSK9 for therapeutic benefits. Preclinical studies have demonstrated synergistic effects between PCSK9 inhibitors and established immunotherapies, offering a novel avenue for combination treatments. The strategic manipulation of PCSK9 to enhance tumor immunity and improve therapeutic outcomes presents an exciting area for further investigations. Understanding the mechanisms by which PCSK9 influences cancer biology and immunity holds promise for the development of novel immunotherapeutic approaches. This review aims to provide a comprehensive analysis of the intricate connections between PCSK9, cancer pathogenesis, tumor immunity, and the potential implications for immunotherapeutic interventions.

Inhibition of DUSP18 impairs cholesterol biosynthesis and promotes anti-tumor immunity in colorectal cancer

Tumor cells reprogram their metabolism to produce specialized metabolites that both fuel their own growth and license tumor immune evasion. However, the relationships between these functions remain poorly understood. Here, we report CRISPR screens in a mouse model of colo-rectal cancer (CRC) that implicates the dual specificity phosphatase 18 (DUSP18) in the establishment of tumor-directed immune evasion. Dusp18 inhibition reduces CRC growth rates, which correlate with high levels of CD8+ T cell activation. Mechanistically, DUSP18 dephosphorylates and stabilizes the USF1 bHLH-ZIP transcription factor. In turn, USF1 induces the SREBF2 gene, which allows cells to accumulate the cholesterol biosynthesis intermediate lanosterol and release it into the tumor microenvironment (TME). There, lanosterol uptake by CD8+ T cells suppresses the mevalonate pathway and reduces KRAS protein prenylation and function, which in turn inhibits their activation and establishes a molecular basis for tumor cell immune escape. Finally, the combination of an anti-PD-1 antibody and Lumacaftor, an FDA-approved small molecule inhibitor of DUSP18, inhibits CRC growth in mice and synergistically enhances anti-tumor immunity. Collectively, our findings support the idea that a combination of immune checkpoint and metabolic blockade represents a rationally-designed, mechanistically-based and potential therapy for CRC.

Dysregulated lipid metabolism networks modulate T-cell function in people with relapsing-remitting multiple sclerosis

Altered cholesterol, oxysterol, sphingolipid, and fatty acid concentrations are reported in blood, cerebrospinal fluid, and brain tissue of people with relapsing-remitting multiple sclerosis (RRMS) and are linked to disease progression and treatment responses. CD4 + T cells are pathogenic in RRMS, and defective T-cell function could be mediated in part by liver X receptors (LXRs)-nuclear receptors that regulate lipid homeostasis and immunity. RNA-sequencing and pathway analysis identified that genes within the 'lipid metabolism' and 'signalling of nuclear receptors' pathways were dysregulated in CD4 + T cells isolated from RRMS patients compared with healthy donors. While LXRB and genes associated with cholesterol metabolism were upregulated, other T-cell LXR-target genes, including genes involved in cellular lipid uptake (inducible degrader of the LDL receptor, IDOL), and the rate-limiting enzyme for glycosphingolipid biosynthesis (UDP-glucosylceramide synthase, UGCG) were downregulated in T cells from patients with RRMS compared to healthy donors. Correspondingly, plasma membrane glycosphingolipids were reduced, and cholesterol levels increased in RRMS CD4 + T cells, an effect partially recapitulated in healthy T cells by in vitro culture with T-cell receptor stimulation in the presence of serum from RRMS patients. Notably, stimulation with LXR-agonist GW3965 normalized membrane cholesterol levels, and reduced proliferation and IL17 cytokine production in RRMS CD4 + T-cells. Thus, LXR-mediated lipid metabolism pathways were dysregulated in T cells from patients with RRMS and could contribute to RRMS pathogenesis. Therapies that modify lipid metabolism could help restore immune cell function.

Liquid-liquid phase separation in diseases

Liquid-liquid phase separation (LLPS), an emerging biophysical phenomenon, can sequester molecules to implement physiological and pathological functions. LLPS implements the assembly of numerous membraneless chambers, including stress granules and P-bodies, containing RNA and protein. RNA-RNA and RNA-protein interactions play a critical role in LLPS. Scaffolding proteins, through multivalent interactions and external factors, support protein-RNA interaction networks to form condensates involved in a variety of diseases, particularly neurodegenerative diseases and cancer. Modulating LLPS phenomenon in multiple pathogenic proteins for the treatment of neurodegenerative diseases and cancer could present a promising direction, though recent advances in this area are limited. Here, we summarize in detail the complexity of LLPS in constructing signaling pathways and highlight the role of LLPS in neurodegenerative diseases and cancers. We also explore RNA modifications on LLPS to alter diseases progression because these modifications can influence LLPS of certain proteins or the formation of stress granules, and discuss the possibility of proper manipulation of LLPS process to restore cellular homeostasis or develop therapeutic drugs for the eradication of diseases. This review attempts to discuss potential therapeutic opportunities by elaborating on the connection between LLPS, RNA modification, and their roles in diseases.

Metabolic dialogues: regulators of chimeric antigen receptor T cell function in the tumor microenvironment

Tumor-infiltrating lymphocytes (TILs) and chimeric antigen receptor (CAR) T cells have demonstrated remarkable success in the treatment of relapsed/refractory melanoma and hematological malignancies, respectively. These treatments have marked a pivotal shift in cancer management. However, as "living drugs," their effectiveness is dependent on their ability to proliferate and persist in patients. Recent studies indicate that the mechanisms regulating these crucial functions, as well as the T cell's differentiation state, are conditioned by metabolic shifts and the distinct utilization of metabolic pathways. These metabolic shifts, conditioned by nutrient availability as well as cell surface expression of metabolite transporters, are coupled to signaling pathways and the epigenetic landscape of the cell, modulating transcriptional, translational, and post-translational profiles. In this review, we discuss the processes underlying the metabolic remodeling of activated T cells, the impact of a tumor metabolic environment on T cell function, and potential metabolic-based strategies to enhance T cell immunotherapy.

Immunometabolism of CD8+ T cell differentiation in cancer

CD8+ cytotoxic T lymphocytes (CTLs) are central mediators of tumor immunity and immunotherapies. Upon tumor antigen recognition, CTLs differentiate from naive/memory-like toward terminally exhausted populations with more limited function against tumors. Such differentiation is regulated by both immune signals, including T cell receptors (TCRs), co-stimulation, and cytokines, and metabolism-associated processes. These immune signals shape the metabolic landscape via signaling, transcriptional and post-transcriptional mechanisms, while metabolic processes in turn exert spatiotemporal effects to modulate the strength and duration of immune signaling. Here, we review the bidirectional regulation between immune signals and metabolic processes, including nutrient uptake and intracellular metabolic pathways, in shaping CTL differentiation and exhaustion. We also discuss the mechanisms underlying how specific nutrient sources and metabolite-mediated signaling events orchestrate CTL biology. Understanding how metabolic programs and their interplay with immune signals instruct CTL differentiation and exhaustion is crucial to uncover tumor-immune interactions and design novel immunotherapies.

Tricking the trickster: precision medicine approaches to counteract leukemia immune escape after transplant

ABSTRACT

Over the last decades, significant improvements in reducing the toxicities of allogeneic hematopoietic cell transplantation (allo-HCT) have widened its use as consolidation or salvage therapy for high-risk hematological malignancies. Nevertheless, relapse of the original malignant disease remains an open issue with unsatisfactory salvage options and limited rationales to select among them. In the last years, several studies have highlighted that relapse is often associated with specific genomic and nongenomic mechanisms of immune escape. In this review we summarize the current knowledge about these modalities of immune evasion, focusing on the mechanisms that leverage antigen presentation and pathologic rewiring of the bone marrow microenvironment. We present examples of how this biologic information can be translated into specific approaches to treat relapse, discuss the status of the clinical trials for patients who relapsed after a transplant, and show how dissecting the complex immunobiology of allo-HCT represents a crucial step toward developing new personalized approaches to improve clinical outcomes.

Identification of a novel monocyte/macrophage-related gene signature for predicting survival and immune response in acute myeloid leukemia

Acute myeloid leukemia (AML) is a heterogeneous hematological tumor with poor immunotherapy effect. This study was to develop a monocyte/macrophage-related prognostic risk score (MMrisk) and identify new therapeutic biomarkers for AML. We utilized differentially expressed genes (DEGs) in combination with single-cell RNA sequencing to identify monocyte/macrophage-related genes (MMGs). Eight genes were selected for the construction of a MMrisk model using univariate Cox regression analysis and LASSO regression analysis. We then validated the MMrisk on two GEO datasets. Lastly, we investigated the immunologic characteristics and advantages of immunotherapy and potential targeted drugs for MMrisk groups. Our study identified that the MMrisk is composed of eight MMGs, including HOPX, CSTB, MAP3K1, LGALS1, CFD, MXD1, CASP1 and BCL2A1. The low MMrisk group survived longer than high MMrisk group (P < 0.001). The high MMrisk group was positively correlated with B cells, plasma cells, CD4 memory cells, Mast cells, CAFs, monocytes, M2 macrophages, Endothelial, tumor mutation, and most immune checkpoints (PD1, Tim-3, CTLA4, LAG3). Furthermore, drug sensitivity analysis showed that AZD.2281, Axitinib, AUY922, ABT.888, and ATRA were effective in high-risk MM patients. Our research shows that MMrisk is a potential biomarker which is helpful to identify the molecular characteristics of AML immunology.

Synergistic immunochemotherapy targeted SAMD4B-APOA2-PD-L1 axis potentiates antitumor immunity in hepatocellular carcinoma

Targeted and immunotherapy combined with interventional therapy can improve the prognosis of advanced cancer patients, and it has become a hot spot to find the new therapeutic schemes, but most of which are not satisfactory. Single-cell RNA sequencing was performed in PDX mouse models with or without TCC therapy. 2-'O-Methylation modification and multiplex immunofluorescence staining were used to explore the function and mechanism of SAMD4B in the immune context of HCC. Here, we propose for the first time a synergistic immunochemotherapy that exerts a potent antitumour effect for patients with advanced hepatocellular carcinoma (HCC) in clinical practice based on three common antitumour drugs and found that HCC patients with new synergistic immunochemotherapy had better three-year overall survival (p = 0.004) and significantly higher survival ratio (increased by 2.3 times) than the control group. We further reveal the immunoregulatory mechanism of synergistic immunochemotherapy through 2'-O-Methylation modification mediated by SAMD4B, a tumour suppressor gene. Mechanistically, SAMD4B, increased by the reduced mutations of upstream genes NOTCH1 and NOTCH2, affected the instability of APOA2 mRNA by 2-'O-Methylation modification of the C-terminus. The decreased APOA2 further attenuated programmed death ligand 1 (PD-L1) level with a direct interaction pattern. The high-SAMD4B tumour tissues contained fewer native CD29+CD8+ T cells, which improved immune microenvironment to achieve the effect of antitumour effect. Overall, we developed a potent synergistic immunochemotherapy strategy that exerts an efficient anti-HCC effect inducing SAMD4B-APOA2-PD-L1 axis to inhibit tumour immune evasion.

Shi-pi-xiao-ji formula suppresses hepatocellular carcinoma by reducing cellular stiffness through upregulation of acetyl-coA acetyltransferase 1

BACKGROUND

Previous studies have shown that the Shi-pi-xiao-ji (SPXJ) herbal decoction formula is effective in suppressing hepatocellular carcinoma (HCC), but the underlying mechanisms are not known. Therefore, this study investigated whether the antitumor effects of the SPXJ formula in treating HCC were mediated by acetyl-coA acetyltransferase 1 (ACAT1)-regulated cellular stiffness. Through a series of experiments, we concluded that SPXJ inhibits the progression of HCC by upregulating the expression level of ACAT1, lowering the level of cholesterol in the cell membrane, and altering the cellular stiffness, which provides a new idea for the research of traditional Chinese medicine against HCC.

AIM

To investigate the anti-tumor effects of the SPXJ formula on the malignant progression of HCC.

METHODS

HCC cells were cultured in vitro with SPXJ-containing serum prepared by injecting SPXJ formula into wild-type mice. The apoptotic rate and proliferative, invasive, and migratory abilities of control and SPXJ-treated HCC cells were compared. Atomic force microscopy was used to determine the cell surface morphology and the Young's modulus values of the control and SPXJ-treated HCC cells. Plasma membrane cholesterol levels in HCC cells were detected using the Amplex Red cholesterol detection kit. ACAT1 protein levels were estimated using western blotting.

RESULTS

Compared with the vehicle group, SPXJ serum considerably reduced proliferation of HCC cells, increased stiffness and apoptosis of HCC cells, inhibited migration and invasion of HCC cells, decreased plasma membrane cholesterol levels, and upregulated ACAT1 protein levels. However, treatment of HCC cells with the water-soluble cholesterol promoted proliferation, migration, and invasion of HCC cells as well as decreased cell stiffness and plasma membrane cholesterol levels, but did not alter the apoptotic rate and ACAT1 protein expression levels compared with the vehicle control.

CONCLUSION

SPXJ formula inhibited proliferation, invasion, and migration of HCC cells by decreasing plasma membrane cholesterol levels and altering cellular stiffness through upregulation of ACAT1 protein expression.

Shi-pi-xiao-ji formula suppresses hepatocellular carcinoma by reducing cellular stiffness through upregulation of acetyl-coA acetyltransferase 1

BACKGROUND

Previous studies have shown that the Shi-pi-xiao-ji (SPXJ) herbal decoction formula is effective in suppressing hepatocellular carcinoma (HCC), but the underlying mechanisms are not known. Therefore, this study investigated whether the antitumor effects of the SPXJ formula in treating HCC were mediated by acetyl-coA acetyltransferase 1 (ACAT1)-regulated cellular stiffness. Through a series of experiments, we concluded that SPXJ inhibits the progression of HCC by upregulating the expression level of ACAT1, lowering the level of cholesterol in the cell membrane, and altering the cellular stiffness, which provides a new idea for the research of traditional Chinese medicine against HCC.

AIM

To investigate the anti-tumor effects of the SPXJ formula on the malignant progression of HCC.

METHODS

HCC cells were cultured in vitro with SPXJ-containing serum prepared by injecting SPXJ formula into wild-type mice. The apoptotic rate and proliferative, invasive, and migratory abilities of control and SPXJ-treated HCC cells were compared. Atomic force microscopy was used to determine the cell surface morphology and the Young’s modulus values of the control and SPXJ-treated HCC cells. Plasma membrane cholesterol levels in HCC cells were detected using the Amplex Red cholesterol detection kit. ACAT1 protein levels were estimated using western blotting.

RESULTS

Compared with the vehicle group, SPXJ serum considerably reduced proliferation of HCC cells, increased stiffness and apoptosis of HCC cells, inhibited migration and invasion of HCC cells, decreased plasma membrane cholesterol levels, and upregulated ACAT1 protein levels. However, treatment of HCC cells with the water-soluble cholesterol promoted proliferation, migration, and invasion of HCC cells as well as decreased cell stiffness and plasma membrane cholesterol levels, but did not alter the apoptotic rate and ACAT1 protein expression levels compared with the vehicle control.

CONCLUSION

SPXJ formula inhibited proliferation, invasion, and migration of HCC cells by decreasing plasma membrane cholesterol levels and altering cellular stiffness through upregulation of ACAT1 protein expression.

Beyond the Barrier: Unraveling the Mechanisms of Immunotherapy Resistance

Immune checkpoint blockade (ICB) induces a remarkable and durable response in a subset of cancer patients. However, most patients exhibit either primary or acquired resistance to ICB. This resistance arises from a complex interplay of diverse dynamic mechanisms within the tumor microenvironment (TME). These mechanisms include genetic, epigenetic, and metabolic alterations that prevent T cell trafficking to the tumor site, induce immune cell dysfunction, interfere with antigen presentation, drive heightened expression of coinhibitory molecules, and promote tumor survival after immune attack. The TME worsens ICB resistance through the formation of immunosuppressive networks via immune inhibition, regulatory metabolites, and abnormal resource consumption. Finally, patient lifestyle factors, including obesity and microbiome composition, influence ICB resistance. Understanding the heterogeneity of cellular, molecular, and environmental factors contributing to ICB resistance is crucial to develop targeted therapeutic interventions that enhance the clinical response. This comprehensive overview highlights key mechanisms of ICB resistance that may be clinically translatable.

Biochemical hallmarks-targeting antineoplastic nanotherapeutics

Tumor microenvironments (TMEs) have received increasing attention in recent years as they play pivotal roles in tumorigenesis, progression, metastases, and resistance to the traditional modalities of cancer therapy like chemotherapy. With the rapid development of nanotechnology, effective antineoplastic nanotherapeutics targeting the aberrant hallmarks of TMEs have been proposed. The appropriate design and fabrication endow nanomedicines with the abilities for active targeting, TMEs-responsiveness, and optimization of physicochemical properties of tumors, thereby overcoming transport barriers and significantly improving antineoplastic therapeutic benefits. This review begins with the origins and characteristics of TMEs and discusses the latest strategies for modulating the TMEs by focusing on the regulation of biochemical microenvironments, such as tumor acidosis, hypoxia, and dysregulated metabolism. Finally, this review summarizes the challenges in the development of smart anti-cancer nanotherapeutics for TME modulation and examines the promising strategies for combination therapies with traditional treatments for further clinical translation.

Metabolic heterogeneity in tumor microenvironment - A novel landmark for immunotherapy

The surrounding non-cancer cells and tumor cells that make up the tumor microenvironment (TME) have various metabolic rhythms. TME metabolic heterogeneity is influenced by the intricate network of metabolic control within and between cells. DNA, protein, transport, and microbial levels are important regulators of TME metabolic homeostasis. The effectiveness of immunotherapy is also closely correlated with alterations in TME metabolism. The response of a tumor patient to immunotherapy is influenced by a variety of variables, including intracellular metabolic reprogramming, metabolic interaction between cells, ecological changes within and between tumors, and general dietary preferences. Although immunotherapy and targeted therapy have made great strides, their use in the accurate identification and treatment of tumors still has several limitations. The function of TME metabolic heterogeneity in tumor immunotherapy is summarized in this article. It focuses on how metabolic heterogeneity develops and is regulated as a tumor progresses, the precise molecular mechanisms and potential clinical significance of imbalances in intracellular metabolic homeostasis and intercellular metabolic coupling and interaction, as well as the benefits and drawbacks of targeted metabolism used in conjunction with immunotherapy. This offers insightful knowledge and important implications for individualized tumor patient diagnosis and treatment plans in the future.

Immunometabolism in atherosclerotic disorders

Cardiovascular diseases (CVDs), including atherosclerosis, myocardial infarction and heart failure, are the leading causes of morbidity and mortality worldwide. Emerging evidence suggests a crucial role for immune cell dysfunction and inflammation in the progression of this complex set of diseases. Recent advances demonstrate that immune cells, tightly linked to CVD pathogenesis, are sensitive to environmental signals and respond by engaging immunometabolic networks that shape their behavior. Inflammatory cues and altered nutrient availability within atherosclerotic plaques or following ischemia synergize to elicit metabolic shifts in immune cells that influence the course of disease pathology. Understanding these metabolic adaptations and how they contribute to cellular dysfunction may reveal novel therapeutic approaches for the treatment of CVD. Here we provide a comprehensive summary of the metabolic reprogramming that occurs in immune cells and their progenitors during CVD, offering insights into the potential therapeutic interventions to mitigate disease progression.

Transient hydroxycholesterol treatment restrains TCR signaling to promote long-term immunity

T cell receptor (TCR) plays a fundamental role in adaptive immunity, and TCR-T cell therapy holds great promise for treating solid tumors and other diseases. However, there is a noticeable absence of chemical tools tuning TCR activity. In our study, we screened natural sterols for their regulatory effects on T cell function and identified 7-alpha-hydroxycholesterol (7a-HC) as a potent inhibitor of TCR signaling. Mechanistically, 7a-HC promoted membrane binding of CD3ε cytoplasmic domain, a crucial signaling component of the TCR-CD3 complex, through alterations in membrane physicochemical properties. Enhanced CD3ε membrane binding impeded the condensation between CD3ε and the key kinase Lck, thereby inhibiting Lck-mediated TCR phosphorylation. Transient treatments of TCR-T cells with 7a-HC resulted in reduced signaling strength, increased memory cell populations, and superior long-term antitumor functions. This study unveils a chemical regulation of TCR signaling, which can be exploited to enhance the long-term efficacy of TCR-T cell therapy.

Immunometabolism in cancer: basic mechanisms and new targeting strategy

Maturing immunometabolic research empowers immune regulation novel approaches. Progressive metabolic adaptation of tumor cells permits a thriving tumor microenvironment (TME) in which immune cells always lose the initial killing capacity, which remains an unsolved dilemma even with the development of immune checkpoint therapies. In recent years, many studies on tumor immunometabolism have been reported. The development of immunometabolism may facilitate anti-tumor immunotherapy from the recurrent crosstalk between metabolism and immunity. Here, we discuss clinical studies of the core signaling pathways of immunometabolism and their inhibitors or agonists, as well as the specific functions of these pathways in regulating immunity and metabolism, and discuss some of the identified immunometabolic checkpoints. Understanding the comprehensive advances in immunometabolism helps to revise the status quo of cancer treatment. An overview of the new landscape of immunometabolism. The PI3K pathway promotes anabolism and inhibits catabolism. The LKB1 pathway inhibits anabolism and promotes catabolism. Overactivation of PI3K/AKT/mTOR pathway and IDO, IL4I1, ACAT, Sirt2, and MTHFD2 promote immunosuppression of TME formation, as evidenced by increased Treg and decreased T-cell proliferation. The LKBI-AMPK pathway promotes the differentiation of naive T cells to effector T cells and memory T cells and promotes anti-tumor immunity in DCs.

Metabolic rewiring and communication in cancer immunity

The immune system shapes tumor development and progression. Although immunotherapy has transformed cancer treatment, its overall efficacy remains limited, underscoring the need to uncover mechanisms to improve therapeutic effects. Metabolism-associated processes, including intracellular metabolic reprogramming and intercellular metabolic crosstalk, are emerging as instructive signals for anti-tumor immunity. Here, we first summarize the roles of intracellular metabolic pathways in controlling immune cell function in the tumor microenvironment. How intercellular metabolic communication regulates anti-tumor immunity, and the impact of metabolites or nutrients on signaling events, are also discussed. We then describe how targeting metabolic pathways in tumor cells or intratumoral immune cells or via nutrient-based interventions may boost cancer immunotherapies. Finally, we conclude with discussions on profiling and functional perturbation methods of metabolic activity in intratumoral immune cells, and perspectives on future directions. Uncovering the mechanisms for metabolic rewiring and communication in the tumor microenvironment may enable development of novel cancer immunotherapies.