Lactic acid promotes PD-1 expression in regulatory T cells in highly glycolytic tumor microenvironments

Tumor-derived lactic acid promotes acetylation of histone H3K27 and differentiation of IL-10-producing regulatory B cells through direct and indirect signaling pathways

Tumor cells are known to enhance glycolysis, even under normoxic conditions, via the Warburg effect, producing excess lactic acid in the tumor microenvironment. Lactic acid enhances the IL-23/IL-17 pathway and induces chronic inflammation. The acidic microenvironment formed by lactic acid suppresses immune cell proliferation and activation. In the present study, we clarified that lactic acid had two novel activities for immune cells. First, lactic acid specifically enhanced acetylation at lysine 27 of histone H3 (H3K27ac) in splenic B cells and monocytes/macrophages, and this epigenetically up-regulates the expression of genes. Acetylation and methylation of other residues of histone H3 were rarely induced. Second, lactic acid induced a particularly-marked enhancement of Il10 gene expression in B cells, leading to an increase in IL-10-producing regulatory B (Breg) cells. Furthermore, two pathways should be involved in both the enhancement of H3K27ac and the induction of Breg cells by lactic acid: a direct pathway that enhances the CD40 signal in B cells, and an indirect pathway that affects B cells by activating the exchange protein directly activated by cAMP (EPAC) 1/2 in non-B cells. In tumor-bearing mice, the levels of H3K27ac of tumor-infiltrating B cells were significantly higher than splenic B cells and were suppressed by intraperitoneal injection of the EPAC1/2 inhibitor. In conclusion, tumor-derived lactic acid increases H3K27ac and IL-10-producing Breg cells, causing the suppression of anti-tumor immunity.

Influence of lactate in resistance to anti‑PD‑1/PD‑L1 therapy: Mechanisms and clinical applications (Review)

Metabolic reprogramming is a prominent characteristic of tumor cells, evidenced by heightened secretion of lactate, which is linked to tumor progression. Furthermore, the accumulation of lactate in the tumor microenvironment (TME) influences immune cell activity, including the activity of macrophages, dendritic cells and T cells, fostering an immunosuppressive milieu. Anti‑programmed cell death protein 1 (PD‑1)/programmed death‑ligand 1 (PD‑L1) therapy is associated with a prolonged survival time of patients with non‑small cell lung cancer. However, some patients still develop resistance to anti‑PD‑1/PD‑L1 therapy. Lactate is associated with resistance to anti‑PD‑1/PD‑L1 therapy. The present review summarizes what is known about lactate metabolism in tumor cells and how it affects immune cell function. In addition, the present review emphasizes the relationship between lactate secretion and immunotherapy resistance. The present review also explores the potential for targeting lactate within the TME to enhance the efficacy of immunotherapy.

PDHX acetylation facilitates tumor progression by disrupting PDC assembly and activating lactylation-mediated gene expression

Deactivation of the mitochondrial pyruvate dehydrogenase complex (PDC) is important for the metabolic switching of cancer cell from oxidative phosphorylation to aerobic glycolysis. Studies examining PDC activity regulation have mainly focused on the phosphorylation of pyruvate dehydrogenase (E1), leaving other post-translational modifications largely unexplored. Here, we demonstrate that the acetylation of Lys 488 of pyruvate dehydrogenase complex component X (PDHX) commonly occurs in hepatocellular carcinoma, disrupting PDC assembly and contributing to lactate-driven epigenetic control of gene expression. PDHX, an E3-binding protein in the PDC, is acetylated by the p300 at Lys 488, impeding the interaction between PDHX and dihydrolipoyl transacetylase (E2), thereby disrupting PDC assembly to inhibit its activation. PDC disruption results in the conversion of most glucose to lactate, contributing to the aerobic glycolysis and H3K56 lactylation-mediated gene expression, facilitating tumor progression. These findings highlight a previously unrecognized role of PDHX acetylation in regulating PDC assembly and activity, linking PDHX Lys 488 acetylation and histone lactylation during hepatocellular carcinoma progression and providing a potential biomarker and therapeutic target for further development.

Tumor β-Catenin Expression Associated With Poor Prognosis to Anti-PD-1 Antibody Monotherapy in Non-small Cell Lung Cancer

Background/Aim

Tumor intrinsic β-catenin signaling has been reported to influence the tumor immune microenvironment and may be a resistance mechanism to immune checkpoint inhibitors in various cancers.

Patients and Methods

We studied the association between tumor β-catenin expression and survival in 50 patients with non-small cell lung cancer (NSCLC) treated with anti-programmed death-1 antibody monotherapy. Tumor β-catenin expression was evaluated by immunohistochemistry.

Results

Patients with positive tumor β-catenin expression (20% of all patients) had worse progression-free survival and overall survival compared with those with negative tumor β-catenin expression. Patients with positive tumor β-catenin expression had reduced CD8+ cell and CD11c+ cell infiltration into tumor nests than those with negative tumor β-catenin expression. RT-PCR of tumor tissue revealed that patients with positive tumor β-catenin expression showed lower gene expression of CD8A, CD4, IFN-γ, BATF3, and CCL4. Knockdown of CTNNB1 tended to increase CCL4 expression, likely mediated by ATF3, in a lung cancer cell line with positive β-catenin expression.

Conclusion

NSCLC patients with positive tumor β-catenin expression that were treated with anti-programmed death-1 antibody monotherapy had poor prognosis.

Association of PD-1 + Treg/PD-1 + CD8 ratio and tertiary lymphoid structures with prognosis and response in advanced gastric cancer patients receiving preoperative treatment

BACKGROUND

Recent studies have highlighted the distinct ratio of PD-1 + Treg/PD-1 + CD8 for prognosis prediction. However, it remains unclear about the association of this ratio and tertiary lymphoid structures (TLS) with prognosis and response to neoadjuvant or conversion therapy in advanced gastric cancer.

METHODS

Firstly, fresh postoperative samples from 68 gastric cancer patients in Renji Hospital were collected. Meanwhile, immune cell infiltration as well as clinical prognosis analysis were conducted. Subsequently, we further systematically evaluated flow cytometry analysis of tumor samples and TLS expression in 38 gastric cancer patients with different response situations after neoadjuvant therapy. Also, a Renji conversion therapy cohort including 10 patients with complete matching samples before and after treatment was established to receive RNA sequencing analysis and multiplex immunohistochemistry (mIHC) tests. The corresponding TLS score and immune cell infiltration were further compared based on therapeutic response variations.

RESULTS

In general, the ratio of PD-1 + Treg/PD-1 + CD8>1 could be regarded as an independent predictor of prognosis in advanced gastric cancer patients. Moreover, PD-1 + Treg/PD-1 + CD8 < 1 and high expression of TLS could indicate better neoadjuvant therapy response and extended survival time in advanved gastric cancer patients. Besides, PD-1 + Treg/PD-1 + CD8 low &TLS high group could predict better progression free survival time (PFS) in complete response (CR) subgroup. In response group after conversion therapy, the number of PD-1 + CD8 + T cells significantly increased, mainly occurring outside the TLSs. Meanwhile, the TLSs were also considerably activated as we could observed.

CONCLUSIONS

This study underlined that combining PD-1 + Treg/PD-1 + CD8 ratio and TLS were significantly associated with prognosis and preoperative treatment response in advanced gastric cancer. Inspiringly, these indicators have the potential to elucidate the immune balance of advanced gastric cancer patients and can accurately guide subsequent therapeutic strategies.

Engineering immunity using metabolically active polymeric nanoparticles

Immune system functions play crucial roles in both health and disease, and these functions are regulated by their metabolic programming. The field of immune engineering has emerged to develop therapeutic strategies, including polymeric nanoparticles (NPs), that can direct immune cell phenotype and function by directing immunometabolic changes. Precise control of bioenergetic processes may offer the opportunity to prevent undesired immune activity and improve disease-specific outcomes. In this review we discuss the role that polymeric NPs can play in shaping immunometabolism and subsequent immune system activity through particle-mediated delivery of metabolically active agents as either structural components or cargo.

Lactylation-driven TNFR2 expression in regulatory T cells promotes the progression of malignant pleural effusion

BACKGROUND

Although tumor necrosis factor receptor 2 (TNFR2) has been recognized as an attractive next-generation candidate target for cancer immunotherapy, the factors that regulate the gene expression and their mechanistic effects on tumor-infiltrating regulatory T cells (Treg cells) remain poorly understood.

METHODS

Single-cell RNA sequencing analysis was employed to analyze the phenotypic and functional differences between TNFR2+ Treg cells and TNFR2- Treg cells. Malignant pleural effusion (MPE) from humans and mouse was used to investigate the potential mechanisms by which lactate regulates TNFR2 expression.

RESULTS

Treg cells with high TNFR2 expression exhibited elevated levels of immune checkpoint molecules. Additionally, the high expression of TNFR2 on Treg cells was positively correlated with a poor prognosis in MPE patients. Moreover, we revealed that lactate upregulated TNFR2 expression on Treg cells, thereby enhancing their immunosuppressive function in MPE. Mechanistically, lactate modulated the gene transcription of transcription factor nuclear factor-κB p65 (NF-κB p65) through histone H3K18 lactylation (H3K18la), subsequently upregulating the gene expression of TNFR2 and expediting the progression of MPE. Notably, lactate metabolism blockade combined with immune checkpoint blockade (ICB) therapy effectively enhanced the efficacy of ICB therapy, prolonged the survival time of MPE mice, and improved immunosuppression in the microenvironment of MPE.

CONCLUSIONS

The study explains the mechanism that regulates TNFR2 expression on Treg cells and its function in MPE progression, providing novel insights into the epigenetic regulation of tumor development and metabolic strategies for MPE treatment by targeting lactate metabolism in Treg cells.

Metabolic immunoengineering approaches to enhance CD8+ T cell-based cancer immunotherapy

Many cancer immunotherapies rely on robust CD8+ T cells capable of eliminating cancer cells and establishing long-term tumor control. Recent insights into immunometabolism highlight the importance of nutrients and metabolites in T cell activation and differentiation. Within the tumor microenvironment (TME), CD8+ tumor-infiltrating lymphocytes (TILs) undergo metabolic adaptations to survive but compromise their effector function and differentiation. Targeting metabolism holds promise for enhancing CD8+ T cell-mediated antitumor immunity. Here, we overview the metabolic features of CD8+ TILs and their impact on T cell effector function and differentiation. We also highlight immunoengineering strategies by leveraging the Yin-Yang of metabolic modulation for improving cancer immunotherapy.

Bifidobacterium animalis ssp. lactis BX-245-fermented milk alleviates tumor burden in mice with colorectal cancer

Colorectal cancer (CRC) arises from the accumulation of abnormal mutations in colorectal cells during prolonged inflammation. This study aimed to investigate the potential of probiotic fermented milk containing the probiotic strain, Bifidobacterium animalis ssp. lactis BX-245 (BX-245), in alleviating tumor burden in CRC mice induced by azoxymethane and dextran sodium sulfate. The study monitored changes in tumor size and number, gut microbiota, metabolomics, and inflammation levels before and after the intervention. Our findings indicate that intragastric administration of BX245-fermented milk effectively modulated the intratumor microbiota, as well as the gut microbiota and its metabolism. We also observed a decreased relative abundance of intratumor Akkermansia in the CRC mice, while the intratumor Parabacteroides exhibited a significant positive correlation with tumor number and weight. Moreover, administering BX245-fermented milk significantly reduced gut barrier permeability, alleviated gut barrier damage, and increased serum interleukin-2 and interferon-γ levels compared with the ordinary fermented milk group. Collectively, our data suggest that administering probiotic fermented milk containing specific functional strains like BX245 could result in a reduction in tumor burden in CRC mice. Conversely, ordinary fermented milk did not show the same tumor-inhibiting effects. The current results are preliminary, and further confirmation is necessary to establish the causal relationship among probiotic milk, changes in gut microbiota, and disease alleviation.

T cell metabolism in kidney immune homeostasis

Kidney immune homeostasis is intricately linked to T cells. Inappropriate differentiation, activation, and effector functions of T cells lead to a spectrum of kidney disease. While executing immune functions, T cells undergo a series of metabolic rewiring to meet the rapid energy demand. The key enzymes and metabolites involved in T cell metabolism metabolically and epigenetically modulate T cells' differentiation, activation, and effector functions, thereby being capable of modulating kidney immune homeostasis. In this review, we first summarize the latest advancements in T cell immunometabolism. Second, we outline the alterations in the renal microenvironment under certain kidney disease conditions. Ultimately, we highlight the metabolic modulation of T cells within kidney immune homeostasis, which may shed light on new strategies for treating kidney disease.

Efficacy, Safety, and Influence on the Tumor Microenvironment of Neoadjuvant Pembrolizumab plus Ramucirumab for PD-L1-Positive NSCLC: A Phase II Trial (EAST ENERGY)

PURPOSE

Angiogenesis inhibitors are known to modify tumor immunity. Combination of angiogenesis inhibitors with immune checkpoint inhibitors has shown efficacy against many types of cancers, including non-small cell lung cancer (NSCLC). We investigated the feasibility of neoadjuvant therapy with pembrolizumab and ramucirumab, a VEGFR-2 antagonist for patients with PD-L1-positive NSCLC, and its influence on the tumor microenvironment.

PATIENTS AND METHODS

Patients with pathologically proven, PD-L1-positive, clinical stage IB to IIIA NSCLC were eligible. Patients received two cycles of pembrolizumab (200 mg/body) and ramucirumab (10 mg/kg) every 3 weeks. Surgery was scheduled 4 to 8 weeks after the last dose. The primary endpoint was the major pathologic response rate by a blinded independent pathologic review. The sample size was 24 patients. Exploratory endpoints were evaluated to elucidate the effects of neoadjuvant therapy on the tumor microenvironment.

RESULTS

The 24 eligible patients were enrolled between July 2019 and April 2022. The major pathologic response rate was 50.0% (90% confidence interval, 31.9%-68.1%). Six patients showed pathologic complete response. Grade 3 adverse events (AE) occurred in nine patients (37.5%), including three immune-related AEs (acute tubulointerstitial nephritis in two cases and polymyalgia rheumatica in one case). There were no grade 4 or 5 AEs. The transcriptome and multiplex IHC results suggested that tumors with greater CD8+ T-cell infiltration and higher expression of effector molecules at the baseline could show better sensitivity to treatment.

CONCLUSIONS

This new neoadjuvant combination of pembrolizumab plus ramucirumab was feasible, and anti-VEGF agents may enhance the effects of immune checkpoint inhibitors.

Regulatory T cell: A promising therapeutic target in tumor microenvironment

ABSTRACT

Regulatory T cell (Tregs) predominantly maintain the immune balance and prevent autoimmunity via their immunosuppressive functions. However, tumor-infiltrating Tregs (TI-Tregs) may mediate tumor immune tolerance in complex tumor microenvironments, resulting in poor prognosis. Distinguishing specific TI-Treg subpopulations from peripheral Tregs and intratumoral conventional T cells (Tconvs) has recently emerged as an important topic in antitumor therapy. In this review, we summarize novel therapeutic approaches targeting both the metabolic pathways and hallmarks of TI-Tregs in preclinical and clinical studies. Although the phenotypic and functional diversity of TI-Tregs remains unclear, our review provides new insights into TI-Treg-based therapies and facilitates precision medicine for tumor treatment.

ATP5J regulates microglial activation via mitochondrial dysfunction, exacerbating neuroinflammation in intracerebral hemorrhage

Microglial-mediated neuroinflammation is crucial in the pathophysiological mechanisms of secondary brain injury (SBI) following intracerebral hemorrhage (ICH). Mitochondria are central regulators of inflammation, influencing key pathways such as alternative splicing, and play a critical role in cell differentiation and function. Mitochondrial ATP synthase coupling factor 6 (ATP5J) participates in various pathological processes, such as cell proliferation, migration, and inflammation. However, the role of ATP5J in microglial activation and neuroinflammation post-ICH is poorly understood. This study aimed to investigate the effects of ATP5J on microglial activation and subsequent neuroinflammation in ICH and to elucidate the underlying mechanisms. We observed that ATP5J was upregulated in microglia after ICH. AAV9-mediated ATP5J overexpression worsened neurobehavioral deficits, disrupted the blood-brain barrier, and increased brain water content in ICH mice. Conversely, ATP5J knockdown ameliorated these effects. ATP5J overexpression also intensified microglial activation, neuronal apoptosis, and inflammatory responses in surrounding tissues post-ICH. ATP5J impaired microglial dynamics and reduced the proliferation and migration of microglia to injury sites. We used oxyhemoglobin (OxyHb) to stimulate BV2 cells and model ICH in vitro. Further in vitro studies showed that ATP5J overexpression enhanced OxyHb-induced microglial functional transformation. Mechanistically, ATP5J silencing reversed dynamin-related protein 1 (Drp1) and mitochondrial fission 1 protein (Fis1) upregulation in microglia post-OxyHb induction; reduced mitochondrial overdivision, excessive mitochondrial permeability transition pore opening, and reactive oxygen species production; restored normal mitochondrial ridge morphology; and partially restored mitochondrial respiratory electron transport chain activity. ATP5J silencing further alleviated OxyHb-induced mitochondrial dysfunction by regulating mitochondrial metabolism. Our results indicate that ATP5J is a key factor in regulating microglial functional transformation post-ICH by modulating mitochondrial dysfunction and metabolism, thereby positively regulate neuroinflammation. By inhibiting ATP5J, SBI following ICH could be prevented. Therefore, ATP5J could be a candidate for molecular and therapeutic target exploration to alleviate neuroinflammation post-ICH.

Targeting caspase-8: a new strategy for combating hepatocellular carcinoma

Hepatocellular carcinoma (HCC) represents the most prevalent form of primary liver cancer and has a high mortality rate. Caspase-8 plays a pivotal role in an array of cellular signaling pathways and is essential for the governance of programmed cell death mechanisms, inflammatory responses, and the dynamics of the tumor microenvironment. Dysregulation of caspase-8 is intricately linked to the complex biological underpinnings of HCC. In this manuscript, we provide a comprehensive review of the regulatory roles of caspase-8 in apoptosis, necroptosis, pyroptosis, and PANoptosis, as well as its impact on inflammatory reactions and the intricate interplay with critical immune cells within the tumor microenvironment, such as tumor-associated macrophages, T cells, natural killer cells, and dendritic cells. Furthermore, we emphasize how caspase-8 plays pivotal roles in the development, progression, and drug resistance observed in HCC, and explore the potential of targeting caspase-8 as a promising strategy for HCC treatment.

Navigating the metabolic landscape of regulatory T cells: from autoimmune diseases to tumor microenvironments

Regulatory T cells (Tregs) are essential for maintaining immune homeostasis, playing crucial roles in modulating autoimmune conditions and contributing to the suppressive tumor microenvironment. Their cellular metabolism governs their generation, stability, proliferation, and suppressive function. Enhancing Treg metabolism to boost their suppressive function offers promising therapeutic potential for alleviating inflammatory symptoms in autoimmune diseases. Conversely, inhibiting Treg metabolism to reduce their suppressive function can enhance the efficacy of traditional immunotherapy in cancer patients. This review explores recent advances in targeting Treg metabolism in autoimmune diseases and the metabolic adaptations of Tregs within the tumor microenvironment that increase their immunosuppressive function.

Targeting metabolic dysfunction of CD8 T cells and natural killer cells in cancer

The importance of metabolic pathways in regulating immune responses is now well established, and a mapping of the bioenergetic metabolism of different immune cell types is under way. CD8 T cells and natural killer (NK) cells contribute to cancer immunosurveillance through their cytotoxic functions and secretion of cytokines and chemokines, complementing each other in target recognition mechanisms. Several immunotherapies leverage these cell types by either stimulating their activity or redirecting their specificity against tumour cells. However, the anticancer activity of CD8 T cells and NK cells is rapidly diminished in the tumour microenvironment, closely linked to a decline in their metabolic capacities. Various strategies have been developed to restore cancer immunosurveillance, including targeting bioenergetic metabolism or genetic engineering. This Review provides an overview of metabolic dysfunction in CD8 T cells and NK cells within the tumour microenvironment, highlighting current therapies aiming to overcome these issues.

Dendrimer/Copper(II) Complex-Mediated siRNA Delivery Disrupts Lactate Metabolism to Reprogram the Local Immune Microenvironment against Tumor Growth and Metastasis

Solid tumors reprogram metabolic pathways to meet their biosynthesis demands, resulting in elevated levels of metabolites in the tumor microenvironment (TME), including lactate. Excessive accumulation and active transportation of lactate within the TME drives tumor progression, metastasis, and immunosuppression. Interruption of TME lactate metabolism is expected to restore antitumor responses and sensitize tumor immunotherapy. Herein, we developed phenylboronic acid- and pyridine-modified poly(amidoamine) dendrimer/copper(II) (Cu(II)) complexes, namely, D-Cu complexes, to deliver monocarboxylate transporter 4 siRNA (siMCT4) and disrupt the tumor lactate shuttle. The D-Cu complexes are shown to have a Cu(II)-mediated chemodynamic effect and T1-weighted magnetic resonance imaging potential (r1 relaxivity = 1.19 mM-1 s-1), enabling effective siMCT4 delivery to inhibit lactate efflux within cancer cells. In combination with a CD11b immune agonist, the treatment of D-Cu/siMCT4 polyplexes in a mouse breast tumor model alleviates local TME immunosuppression, leading to excellent inhibition of both primary tumor growth and lung metastasis.

Hypoxia reconstructed colorectal tumor microenvironment weakening anti-tumor immunity: construction of a new prognosis predicting model through transcriptome analysis

Background

Hypoxia in the tumor microenvironment (TME) plays a pivotal role in the progression and prognosis of colorectal cancer (CRC). However, effective methods for assessing TME hypoxia remain lacking. This study aims to develop a novel hypoxia-related prognostic score (HPS) based on hypoxia-associated genes to improve CRC prognostication and inform treatment strategies.

Methods

Transcriptomic data from CRC patients were analyzed using Lasso regression to identify hypoxia-associated genes with the strongest prognostic significance. The identified genes were validated in vitro by assessing their expression under normoxic and hypoxic conditions in normal intestinal epithelial cells and CRC tumor cell lines. Functional relevance was explored through differential gene expression analysis, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, and protein-protein interaction (PPI) network construction. The association of HPS with extracellular matrix (ECM) composition, immune cell infiltration, and immune suppression was also investigated.

Results

Seven hypoxia-associated signature genes were identified, each demonstrating a strong correlation with CRC prognosis. The hypoxia-related prognostic score (HPS), derived from these genes, was significantly linked to changes in the TME. Specifically, HPS values were associated with alterations in ECM composition and distinct immune cell infiltration patterns. Higher HPS values corresponded to increased infiltration of immune-suppressive cells and reduced presence of anti-tumor immune cells. This imbalance promoted an immune-suppressive TME, facilitating tumor progression and immune evasion.

Conclusions

The hypoxia-related prognostic score (HPS) captures the regulatory influence of TME hypoxia on immune responses, offering valuable insights into its role in tumor progression. HPS holds promise as a prognostic tool and a guide for developing personalized treatment strategies in CRC.

Dual impacts of serine/glycine-free diet in enhancing antitumor immunity and promoting evasion via PD-L1 lactylation

The effect of the serine/glycine-free diet (-SG diet) on colorectal cancer (CRC) remains unclear; meanwhile, programmed death-1 (PD-1) inhibitors are less effective for most CRC patients. Here, we demonstrate that the -SG diet inhibits CRC growth and promotes the accumulation of cytotoxic T cells to enhance antitumor immunity. Additionally, we also identified the lactylation of programmed death-ligand 1 (PD-L1) in tumor cells as a mechanism of immune evasion during cytotoxic T cell-mediated antitumor responses, and blocking the PD-1/PD-L1 signaling pathway is able to rejuvenate the function of CD8+ T cells recruited by the -SG diet, indicating the potential of combining the -SG diet with immunotherapy. We conducted a single-arm, phase I study (ChiCTR2300067929). The primary outcome suggests that the -SG diet is feasible and safe for regulating systemic immunity. Secondary outcomes include patient tolerability and potential antitumor effects. Collectively, our findings highlight the promising therapeutic potential of the -SG diet for treating solid tumors.

PCDHGA10 as a potential prognostic biomarker and correlated with immune infiltration in gastric cancer

Background

Gastric cancer (GC) is one of the most common malignant tumors and is associated with poor prognosis. To improve the prognosis of GC patients, an effective immune-related prognostic biomarker is urgent. Here, we aim to explore the correlation between the expression of procalcitonin gamma subfamily A, 10 (PCDHGA10) and clinicopathological characteristics, especially its relation with tumor-infiltrating immune cells (TILs) in GC.

Methods

The differential mRNA expression of PCDHGA10 between GC tissues and normal gastric mucosa and prognostic potential were assessed from The Cancer Genome Atlas (TCGA). Then, based on tissue microarrays (TMAs) with multiplex immunohistochemistry (mIHC) from GC patients, we statistically assess the correlation between PCDHGA10 protein expression and the clinical profiles and prognosis of the patients. Additionally, with IHC and mIHC, we applied the machine-learning algorithms to evaluate the localization and expression levels of TILs and immune checkpoints in the tumor microenvironment. We analyzed the relationship between PCDHGA10 protein expression and TILs and immune checkpoints.

Results

Through the database and TMA analysis, the expression of PCDHGA10 was significantly higher in GC tissues compared with normal tissues. High PCDHGA10 expression independently predicted poor prognosis in GC. Additionally, elevated PCDHGA10 expression was positively associated with the number of CD8+ T cells, CD68+ macrophages, Foxp3+ T cells, and CD4+ T cells in GC tissues and the stromal region. Besides, the expression of PCDHGA10 was positively correlated with immune checkpoints, including CTLA-4, LAG3, and PD-L1.

Conclusions

PCDHGA10 might be a potential prognostic marker and an immunological therapeutic target for GC.

PI3K/AKT/mTOR and PD‑1/CTLA‑4/CD28 pathways as key targets of cancer immunotherapy (Review)

T cells play an important role in cancer, and energy metabolism can determine both the proliferation and differentiation of T cells. The inhibition of immune checkpoint molecules programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte associated protein 4 (CTLA-4) are a promising cancer treatment. In recent years, research on CD28 has increased. Although numerous reports involve CD28 and its downstream PI3K/AKT/mTOR signaling mechanisms in T cell metabolism, they have not yet been elucidated. A literature search strategy was used for the databases PubMed, Scopus, Web of Science and Cochrane Library to ensure broad coverage of medical and scientific literature, using a combination of keywords including, but not limited to, 'lung cancer' and 'immunotherapy'. Therefore, the present study reviewed the interaction and clinical application of the PD-1/CTLA-4/CD28 and PI3K/AKT/mTOR pathways in T cells, aiming to provide a theoretical basis for immunotherapy in clinical cancer patients.

Sonocatalytic oncolysis microbiota curb intrinsic microbiota lactate metabolism and blockade CD24-Siglec10 immune escape to revitalize immunological surveillance

Intrinsic lactate retention of chemically- or genetically-engineered bacteria therapy aggravates tumor immunosuppression, which will collaborate with immune escape to cause immunological surveillance failure. To address them, sonocatalytic oncolysis Escherichia coli (E.coli) that chemically chelated anti-CD24 and TiO1+x have been engineered to blockade CD24-siglec10 interaction, regulate microbiota colonization and curb its lactate metabolism, which are leveraged to revitalize immunological surveillance and repress breast cancer. The chemically-engineered E.coli inherited their parent genetic information and expansion function. Therefore, their intrinsic hypoxia tropism and CD24 targeting allow them to specifically accumulate and colonize in solid breast cancer to lyse tumor cells. The conjugated CD24 antibody is allowed to blockade CD24-Siglec10 signaling axis and revitalize immunological surveillance. More significantly, the chelated TiO1+x sonosensitizers produce ROS to render bacteria expansion controllable and curb immunosuppression-associated lactate birth that are usually neglected. Systematic experiments successfully vlaidate hypoxia-objective active targeting, sonocatalytic therapy, microbiota expansion-enabled oncolysis, CD24-Siglec10 communication blockade and precise microbiota abundance & lactate metabolism attenuations. These actions contribute to the potentiated anti-tumor immunity and activated anti-metastasis immune memory against breast cancer development. Our pioneering work provide a route to sonocatalytic cancer immunotherapy.

Expression of nuclear receptors and glucose metabolic pathway proteins in sebaceous carcinoma: Androgen receptor and monocarboxylate transporter 1 have a key role in disease progression

Standard systemic treatments are not consistently effective for treating unresectable or advanced sebaceous carcinoma (SC). The present study investigated the pathogenic roles of nuclear receptors (NRs), glucose metabolic dysregulation and immune checkpoint proteins in SC as prognostic markers or therapeutic targets. Patients with pathologically confirmed SC between January 2002 and December 2019 at three university hospitals in South Korea were included in the present study. Immunohistochemistry was performed on paraffin-embedded tumor tissues for glucocorticoid receptors (GR), androgen receptors (AR), estrogen receptors (ER), progesterone receptors (PR), glucose transporter 1 (GLUT1), monocarboxylate transporters (MCT1 and MCT4), CD147, phosphorylated adenosine monophosphate-activated protein kinase (pAMPK) and the immune checkpoint protein, programmed cell death-ligand 1 (PD-L1). The results were semi-quantitatively assessed and the associations of these proteins with various clinicopathological parameters were determined. A total of 39 cases of SC comprising 19 periocular and 20 extraocular tumors were enrolled. NRs were frequently detected in the tumor nuclei, with GR having the highest frequency (89.7%), followed by AR, ER (both 51.3%) and PR (41.0%). Regarding glucose metabolism, CD147, GLUT1 and MCT1 were highly expressed at 100, 89.7 and 87.2%, respectively, whereas MCT4 and pAMPK expression levels were relatively low at 38.5 and 35.9%, respectively. Membranous expression of PD-L1 was detected in five cases (12.8%), four of which were extraocular. In the multivariate analysis, advanced stage, low AR positivity and high MCT1 expression were independent poor prognostic factors for metastasis-free survival (all P<0.05). The present results suggested that hormonal and metabolic dysregulation may be associated with the pathogenesis of SC, and that AR and MCT1 in particular may serve as prognostic indicators and potential therapeutic targets. Additionally, ~10% of SC cases exhibited PD-L1 expression within the druggable range, and these patients are expected to benefit from treatment with immune checkpoint inhibitors.

The role of glycolysis in tumorigenesis: From biological aspects to therapeutic opportunities

Glycolytic metabolism generates energy and intermediates for biomass production. Tumor-associated glycolysis is upregulated compared to normal tissues in response to tumor cell-autonomous or non-autonomous stimuli. The consequences of this upregulation are twofold. First, the metabolic effects of glycolysis become predominant over those mediated by oxidative metabolism. Second, overexpressed components of the glycolytic pathway (i.e. enzymes or metabolites) acquire new functions unrelated to their metabolic effects and which are referred to as "moonlighting" functions. These functions include induction of mutations and other tumor-initiating events, effects on cancer stem cells, induction of increased expression and/or activity of oncoproteins, epigenetic and transcriptional modifications, bypassing of senescence and induction of proliferation, promotion of DNA damage repair and prevention of DNA damage, antiapoptotic effects, inhibition of drug influx or increase of drug efflux. Upregulated metabolic functions and acquisition of new, non-metabolic functions lead to biological effects that support tumorigenesis: promotion of tumor initiation, stimulation of tumor cell proliferation and primary tumor growth, induction of epithelial-mesenchymal transition, autophagy and metastasis, immunosuppressive effects, induction of drug resistance and effects on tumor accessory cells. These effects have negative consequences on the prognosis of tumor patients. On these grounds, it does not come to surprise that tumor-associated glycolysis has become a target of interest in antitumor drug discovery. So far, however, clinical results with glycolysis inhibitors have fallen short of expectations. In this review we propose approaches that may allow to bypass some of the difficulties that have been encountered so far with the therapeutic use of glycolysis inhibitors.

Crosstalk between lactate and tumor-associated immune cells: clinical relevance and insight

Lactate, which was traditionally viewed as a metabolic byproduct of anaerobic glycolysis, has emerged as a significant signaling molecule involved in the development of tumors. Current studies highlight its dual function, where it not only fuels tumor development but also modulates immune responses. Lactate has an effect on various tumor-associated immune cells, promoting immunosuppressive conditions that facilitate tumor growth and immune evasion. This phenomenon is strongly associated with the Warburg effect, a metabolic shift observed in many cancers that favors glycolysis over oxidative phosphorylation, resulting in elevated lactate production. Exploring the complex interplay between lactate metabolism and tumor immunity provides a novel understanding regarding the mechanisms of tumor immune evasion and resistance to therapies. This review discusses the unique biology of lactate in the TME, its impact on immune cell dynamics, and its potential as a tumor treatment target.

From metabolic byproduct to immune modulator: the role of lactate in tumor immune escape

Lactic acid, a key metabolic byproduct within the tumor microenvironment, has garnered significant attention for its role in immune evasion mechanisms. Tumor cells produce and release large amounts of lactic acid into the tumor microenvironment through aberrant glycolysis via the Warburg effect, leading to a drop in pH. Elevated lactic acid levels profoundly suppress proliferation capacity, cytotoxic functions, and migratory abilities of immune effector cells such as macrophages and natural killer cells at the tumor site. Moreover, lactic acid can modulate the expression of surface molecules on immune cells, interfering with their recognition and attack of tumor cells, and it regulates signaling pathways that promote the expansion and enhanced function of immunosuppressive cells like regulatory T cells, thereby fostering immune tolerance within the tumor microenvironment. Current research is actively exploring strategies targeting lactic acid metabolism to ameliorate tumor immune evasion. Key approaches under investigation include inhibiting the activity of critical enzymes in lactic acid production to reduce its synthesis or blocking lactate transporters to alter intracellular and extracellular lactate distribution. These methods hold promise when combined with existing immunotherapies such as immune checkpoint inhibitors and chimeric antigen receptor T-cell therapies to enhance the immune system's ability to eliminate tumor cells. This could pave the way for novel combinatorial treatment strategies in clinical cancer therapy, effectively overcoming tumor immune evasion phenomena, and ultimately improving overall treatment efficacy.

Lactate promotes H3K18 lactylation in human neuroectoderm differentiation

In mammals, early embryonic gastrulation process is high energy demanding. Previous studies showed that, unlike endoderm and mesoderm cells, neuroectoderm differentiated from human embryonic stem cells relied on aerobic glycolysis as the major energy metabolic process, which generates lactate as the final product. Here we explored the function of intracellular lactate during neuroectoderm differentiation. Our results revealed that the intracellular lactate level was elevated in neuroectoderm and exogenous lactate could further promote hESCs differentiation towards neuroectoderm. Changing intracellular lactate levels by sodium lactate or LDHA inhibitors had no obvious effect on BMP or WNT/β-catenin signaling during neuroectoderm differentiation. Notably, histone lactylation, especially H3K18 lactylation was significant upregulated during this process. We further performed CUT&Tag experiments and the results showed that H3K18la is highly enriched at gene promoter regions. By analyzing data from CUT&Tag and RNA-seq experiments, we further identified that four genes, including PAX6, were transcriptionally upregulated by lactate during neuroectoderm differentiation. A H3K18la modification site at PAX6 promoter was verified and exogenous lactate could also rescue the level of PAX6 after shPAX6 inhibition.

Circadian immunometabolism: A future insight for targeted therapy in cancer

Circadian rhythms send messages to regulate the sleep-wake cycle in living beings, which, regulate various biological activities. It is well known that altered sleep-wake cycles affect host metabolism and significantly deregulate the host immunity. The dysregulation of circadian-related genes is critical for various malignancies. One of the hallmarks of cancer is altered metabolism, the effects of which spill into surrounding microenvironments. Here, we review the emerging literature linking the circadian immunometabolic axis to cancer. Small metabolites are the products of various metabolic pathways, that are usually perturbed in cancer. Genes that regulate circadian rhythms also regulate host metabolism and control metabolite content in the tumor microenvironment. Immune cell infiltration into the tumor site is critical to perform anticancer functions, and altered metabolite content affects their trafficking to the tumor site. A compromised immune response in the tumor microenvironment aids cancer cell proliferation and immune evasion, resulting in metastases. The role of circadian rhythms in these processes is largely overlooked and demands renewed attention in the search for targets against cancer growth and spread. The precision medicine approach requires targeting the circadian immune metabolism in cancer.

CD19+CD73+ B cells infiltration indicates poor prognosis and unfavorable responses to immunotherapy in gastric cancer

OBJECTIVES

Cluster of Differentiation 73 (CD73) is expressed on immune cells and plays a significant role in tumor inhibition by suppressing antitumor immunity. The objectives of this study were to explore the expression and functional mechanisms of CD73 on B cells in patients with gastric cancer (GC).

METHODS

The prognostic significance of CD19+CD73+ B cells was evaluated in 390 GC patients through dual immunohistochemistry staining. Flow cytometry was employed to analyze the phenotype of the CD19 subpopulation using fresh tumor and non-tumor tissue samples from 8 GC patients. A bioinformatics analysis of CD19+CD73+ B cells was also performed within the scRNA-seq cohort, and the CD19+ B cell subtype was assessed using multiple immunofluorescence staining.

RESULTS

The infiltration of CD19+CD73+ B cells was observed to be elevated in gastric cancer (GC) tissue compared to normal tissues. A strong correlation was observed between high CD19+CD73+ B cell infiltration, poor overall survival, and diminished responsiveness to neoadjuvant immunotherapy in GC. These cells emerged as a novel subset of regulatory B cells (Bregs) linked to adenosine metabolism and the exhaustion of CD8+ T cells. The CD19+CD73+ B cells also correlated with the production of immunosuppressive cytokines IL-10 and TGFB1. Further analysis indicated an association between CD19+CD73+ B cells and advanced-stage GC.

CONCLUSIONS

The presence of CD19+CD73+ B cells in GC may serve as a prognostic indicator for clinical outcomes and a predictive marker for poor responsiveness to neoadjuvant immunotherapy. The correlation between the presence of CD19+CD73+ B cells and CD8+ T cell exhaustion, along with immunosuppression, highlights the tumor-promoting function of these cells.

Immune dynamics shaping pre-metastatic and metastatic niches in liver metastases: from molecular mechanisms to therapeutic strategies

Liver metastases are commonly detected in the advanced stages of various malignant tumors, representing a significant clinical challenge. Throughout the process of liver metastases formation, immune cells play a pivotal role, particularly in the pre-metastatic and metastatic niches within the liver. Immune cells establish extensive and intricate interactions with tumor cells and other components in the liver, collectively promoting and sustaining the growth of liver metastases. Despite the limited efficacy of existing therapeutic modalities against some advanced liver metastases, novel immune-based treatment approaches are continuously being explored and validated. Building on the systematic elucidation of the immunosuppressive characteristics of liver metastases, we explored the potential of novel immunotherapies applicable to patients with liver metastases from multiple dimensions.

Analysis of immune status and prognostic model incorporating lactic acid metabolism-associated genes

BACKGROUND

Cancer development is intricately linked with metabolic dysregulation, including lactic acid metabolism, which plays a pivotal role in tumor progression and immune evasion. However, its specific implications in gastric adenocarcinoma (STAD) remain unclear. This study introduces a novel methodology to evaluate lactic acid metabolism comprehensively in STAD, aiming to elucidate its prognostic significance and impact on immunotherapy efficacy. Targeted therapies directed at key lactic acid metabolism genes (LMGs) identified within the tumor microenvironment (TME) hold promise for personalized treatment strategies.

METHODS

Lactic acid metabolism patterns were assessed in 415 STAD patients using a panel of 21 LMGs. Cox regression and Lasso regression analyses were employed to develop a predictive risk model based on differentially expressed genes (DEGs). Validation of the model was conducted using independent cohorts from the GEO and TCGA databases, as well as additional datasets focused on immunotherapy responses. Further investigations into TME dynamics of lactic acid metabolism included functional assays targeting SLC16A3, a pivotal gene identified through our analyses.

RESULTS

Patients were stratified into distinct risk groups based on their lactic acid metabolism profiles. Low-risk patients exhibited attenuated lactic acid metabolism, correlating with favorable clinical outcomes characterized by prolonged survival and enhanced responsiveness to immunotherapy. Notably, tumor cells within the TME demonstrated heightened levels of active lactic acid metabolism, particularly impacting tumor-infiltrating lymphocytes such as CD8 + T cells and regulatory T cells. Mechanistically, SLC16A3 emerged as a critical regulator promoting STAD cell proliferation, invasion, and migration while modulating the metabolic landscape.

CONCLUSION

This study underscores the prognostic value of a lactic acid metabolism-based model in STAD, providing insights into its potential as a predictive biomarker for patient stratification and therapeutic targeting. The findings highlight SLC16A3 as a promising candidate for therapeutic intervention aimed at modulating lactic acid metabolism in the TME, thereby advancing personalized treatment strategies in gastric cancer management.

Metabolic Reprogramming of Immune Cells in the Tumor Microenvironment

Metabolic reprogramming of immune cells within the tumor microenvironment (TME) plays a pivotal role in shaping tumor progression and responses to therapy. The intricate interplay between tumor cells and immune cells within this ecosystem influences their metabolic landscapes, thereby modulating the immune evasion tactics employed by tumors and the efficacy of immunotherapeutic interventions. This review delves into the metabolic reprogramming that occurs in tumor cells and a spectrum of immune cells, including T cells, macrophages, dendritic cells, and myeloid-derived suppressor cells (MDSCs), within the TME. The metabolic shifts in these cell types span alterations in glucose, lipid, and amino acid metabolism. Such metabolic reconfigurations can profoundly influence immune cell function and the mechanisms by which tumors evade immune surveillance. Gaining a comprehensive understanding of the metabolic reprogramming of immune cells in the TME is essential for devising novel cancer therapeutic strategies. By targeting the metabolic states of immune cells, it is possible to augment their anti-tumor activities, presenting new opportunities for immunotherapeutic approaches. These strategies hold promise for enhancing treatment outcomes and circumventing the emergence of drug resistance.

The hallmarks of cancer immune evasion

According to the widely accepted "three Es" model, the host immune system eliminates malignant cell precursors and contains microscopic neoplasms in a dynamic equilibrium, preventing cancer outgrowth until neoplastic cells acquire genetic or epigenetic alterations that enable immune escape. This immunoevasive phenotype originates from various mechanisms that can be classified under a novel "three Cs" conceptual framework: (1) camouflage, which hides cancer cells from immune recognition, (2) coercion, which directly or indirectly interferes with immune effector cells, and (3) cytoprotection, which shields malignant cells from immune cytotoxicity. Blocking the ability of neoplastic cells to evade the host immune system is crucial for increasing the efficacy of modern immunotherapy and conventional therapeutic strategies that ultimately activate anticancer immunosurveillance. Here, we review key hallmarks of cancer immune evasion under the "three Cs" framework and discuss promising strategies targeting such immunoevasive mechanisms.

Regulatory T cells in immune checkpoint blockade antitumor therapy

Regulatory T cells (Tregs), an essential component of the human immune system, are a heterogeneous group of T lymphocytes with the ability to suppress immune responses and maintain immune homeostasis. Recent evidence indicates that Tregs may impair antitumor immunity and facilitate cancer progression by weakening functions of effector T cells (Teffs). Consequently, targeting Tregs to eliminate them from tumor microenvironments to improve Teffs' activity could emerge as an effective strategy for cancer immunotherapy. This review outlines the biology of Tregs, detailing their origins, classification, and crucial markers. Our focus lies on the complex role of Tregs in cancer's development, progression and treatment, particularly on their suppressive role upon antitumor responses via multiple mechanisms. We delve into Tregs' involvement in immune checkpoint blockade (ICB) therapy, their dual effect on cancer immunotherapy and their potential biomarkers for ICB therapy effectiveness. We also summarize advances in the therapies that adjust Tregs to optimize ICB therapy, which may be crucial for devising innovative cancer treatment strategies.

A novel hypoxia- and lactate metabolism-related prognostic signature to characterize the immune landscape and predict immunotherapy response in osteosarcoma

Background

Immunotherapy has shown considerable promise in cancer treatment, yet only a minority of osteosarcoma patients derive benefits from this approach. Hypoxia and lactate metabolism are two predominant characteristics of the tumor microenvironment. These features are crucial for molding the immune landscape and thus have the potential to act as predictive indicators for immunotherapy response.

Methods

Prognostic modeled genes were identified through univariate and multivariate Cox regression as well as LASSO regression analyses. The tumor microenvironment was evaluated using ESTIMATE, CIBERSORT, and ImmuCellAI analyses. Tide prediction and expression of immune checkpoints, MHC molecules, chemokines, interleukins, interferons, receptors, and other cytokines were utilized to estimate immunotherapy efficacy. Single-cell analysis was performed to demonstrate the expression of modeled genes among various immune cell types. Experimental validation was carried out to verify the expression and functions of SFXN4 and SQOR.

Results

A potent signature was constructed with 8 genes related to hypoxia and lactate metabolism, including MAFF, COL5A2, FAM162A, SQOR, UQCRB, SFXN4, PFKFB2 and COX6A2. A nomogram incorporating risk scores and other clinical features demonstrated excellent predictive capacity. Osteosarcoma patients with high-risk scores exhibited poor prognosis and more "cold" tumor characteristics. According to the ESTIMATE algorithm, these patients displayed lower immune, stromal, and ESTIMATE scores, partially attributed to inadequate infiltration of key immunocytes. The Ciborsort analysis similarly indicated that high-risk individuals had diminished infiltration of critical anti-tumor immune cells such as Cytotoxic T cells, CD4+ T cells, and NK cells. The low expression levels of certain immune checkpoints, MHC molecules, chemokines, interleukins, interferons, receptors, and other cytokines in high-risk cases suggested their unsatisfactory responses to immune treatment. Tide prediction further demonstrated that fewer individuals classified as high risk may exhibit sensitivity to immune checkpoint inhibitor therapy. Notably, SFXN4 was found to be highly expressed in osteosarcoma tissues and cells; it promoted the growth, migration, and invasion of osteosarcoma cells, while SQOR had the opposite effect.

Conclusion

Our research has developed a robust hypoxia- and lactate metabolism-related gene signature, providing a solid theoretical foundation for prognosis prediction, classification of "cold" and "hot" tumors, accessing immunotherapy response, and directing personalized treatment for osteosarcoma.

Photo-Thermally Controllable Tumor Metabolic Modulation to Assist T Cell Activation for Boosting Immunotherapy

Background

Glycolysis is crucial for tumor cell proliferation, supporting their energy needs and influencing the tumor microenvironment (TME). On one hand, increased lactate levels produced by glycolysis acidifies the TME, inhibiting T cell activity. On the other hand, glycolysis promotes the expression of PD-L1 through various mechanisms, facilitating immune evasion. Therefore, controlled modulation of glycolysis in tumor cells to subsequently improve the immune tumor microenvironment holds significant implications for clinical cancer treatment and immune regulation.

Methods

To reverse the immunosuppressive microenvironment caused by tumor glycolysis and reduce tumor immune escape, we developed a photo-thermal-controlled precision drug delivery platform to regulate tumor metabolism and aid in the activation of T cells, thereby enhancing immunotherapy. First, hollow mesoporous Prussian blue (HPB) was prepared, and the glycolysis inhibitor 3-bromopyruvate (3-BrPA) was encapsulated within HPB using the phase-change material 1-tetradecanol, resulting in B/T-H. This product was then modified with tumor cell membranes to obtain a photo-thermal controllable regulator (B/T-H@Membrane, B/T-HM).

Results

Due to the excellent drug loading and photo-thermal properties of HPB, upon reaching the tumor, B/T-HM can rapidly heat under 808 nm irradiation, causing the 1-tetradecanol to transition to a liquid phase and release 3-BrPA, which effectively inhibits tumor glycolysis through the HK2 pathway, thereby reducing tumor cell proliferation, decreasing lactate production, and downregulating tumor PD-L1 expression. In synergy with photo-thermal and αPD-1, this photo-thermally controllable metabolic-immune therapy effectively activates T cells to eliminate tumor.

Conclusion

In response to the changes in immune microenvironment caused by tumor metabolism, a photo-thermal precision-controlled drug delivery platform was successfully developed. This platform reshapes the tumor immunosuppressive microenvironment, providing a new approach for T cell-based tumor immunotherapy. It also opens new avenues for photo-thermal controllable metabolic-immune therapy.

SUGT1 regulates the progression of ovarian cancer through the AKT/PI3K/mTOR signaling pathway

This study investigates the expression and functional roles of SUGT1 in ovarian cancer, utilizing data from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) projects. Our analyses reveal that SUGT1 is significantly upregulated in ovarian cancer tissues compared to normal controls. We further explore the prognostic value of SUGT1, where elevated expression correlates with poorer patient outcomes, particularly in ovarian cancer. The functional implications of SUGT1 in cancer biology were assessed through in vitro and in vivo experiments. Gene Set Enrichment Analysis (GSEA) indicates a significant association between high SUGT1 expression and the activation of glycolytic pathways, suggesting a potential role in metabolic reprogramming. Inhibition of SUGT1 via siRNA in ovarian cancer cell lines results in decreased proliferation and increased apoptosis, along with reduced migration and invasion capabilities. Additionally, our study identifies the transcription factor ELF1 as a significant regulator of SUGT1 expression. Through promoter analysis and chromatin immunoprecipitation, we demonstrate that ELF1 directly binds to the SUGT1 promoter, enhancing its transcription. This regulatory mechanism underscores the importance of transcriptional control in cancer metabolism, providing insights into potential therapeutic targets. Our findings establish SUGT1 as a crucial player in the oncogenic processes of ovarian cancer, influencing both metabolic pathways and transcriptional regulation. This highlights its potential as a biomarker and therapeutic target in managing ovarian cancer.

TGF-β: an active participant in the immune and metabolic microenvironment of multiple myeloma : TGF-β in the microenvironment of multiple myeloma

Although substantial quantities of potent therapies for multiple myeloma (MM) have been established, MM remains an incurable disease. In recent years, our understanding of the initiation, development, and metastasis of cancers has made a qualitative leap. Cancers attain the abilities to maintain proliferation signals, escape growth inhibitors, resist cell death, induce angiogenesis, and more importantly, escape anti-tumor immunity and reprogram metabolism, which are the hallmarks of cancers. Besides, different cancers have different tumor microenvironments (TME), thus, we pay more attention to the TME in the pathogenesis of MM. Many researchers have identified that myeloma cells interact with the components of TME, which is beneficial for their survival, ultimately causing the formation of immunosuppressive and high-metabolism TME. In the process, transforming growth factor-β (TGF-β), as a pivotal cytokine in the TME, controls various cells' fates and influences numerous metabolic pathways, including inhibiting immune cells to infiltrate the tumors, suppressing the activation of anti-tumor immune cells, facilitating more immunosuppressive cells, enhancing glucose and glutamine metabolism, dysregulating bone metabolism and so on. Thus, we consider TGF-β as the tumor promoter. However, in healthy cells and the early stage of tumors, it functions as a tumor suppressor. Due to the effect of context dependence, TGF-β has dual roles in TME, which attracts us to further explore whether targeting it can overcome obstacles in the treatment of MM by regulating the progression of myeloma, molecular mechanisms of drug resistance, and various signaling pathways in the immune and metabolic microenvironment. In this review, we predominantly discuss that TGF-β promotes the development of MM by influencing immunity and metabolism.

CD8+ T cells infiltrating into tumors were controlled by immune status of pulmonary lymph nodes and correlated with non-small cell lung cancer (NSCLC) patients' prognosis treated with chemoimmunotherapy

PURPOSE

Neoadjuvant chemoimmunotherapy has the potential to reduce tumor burden, improve the pathological complete response (pCR) rate, and significantly prolong patients' disease-free survival (DFS). However, the treatment's effectiveness varies among NSCLC patients. The immunological mechanisms contributing to tumor regression still require further exploration and elucidation.

METHODS

The immune status of patients' local tumor microenvironment (TME) before and after neoadjuvant chemoimmunotherapy, their paired pulmonary lymph nodes (11th LNs) after therapy, including infiltrating immune cell densities and their correlations, were analyzed using multiplex immunofluorescence.

RESULTS

Fifty-six NSCLC patients undergoing neoadjuvant chemoimmunotherapy were enrolled and subsequently underwent surgical resection and pathological evaluation. Among these, 19 patients achieved a pCR, 6 patients exhibited a major pathological response (MPR), and 31 patients did not achieve MPR. There were no significant difference in the densities of CD8+ T cell, Treg and Dendritic cell (DC) in patients' TME before neoadjuvant therapy (n = 26, P = 0.091, P = 0.753, P = 0.905, respectively), but after treament, these immune cells' dynamics were significantly different between different response group. CD8+ T cell densities were increased in pCR gourp (P = 0.006), but not in non-pCR group (P = 0.389); the densities of Treg were increased in non-pCR gourp (P = 0.0004), but DC were significantly decreased in non-pCR gourp (P = 0.005). After surgery, the TME were also significantly different: patients achieving pCR typically demonstrated high densities of CD8+ T cell, DC and low densities of Tregs (P = 0.0001, P < 0.0001 and P = 0.0004). The immune status of 11th LNs also exhibited significant differences. DC densities were much higher in pCR patients, whereas Treg in the pCR group were significantly lower than those in the non-pCR group (P = 0.0008 and P = 0.003). Furthermore, the densities of DC in the TME showed a moderate positive correlation with DC in 11th LNs (P = 0.0002), while the densities of Tregs in the TME exhibited a moderate negative correlation with DC densities in 11th LNs (P = 0.03). Patients who had high densities of CD8+ T cell in the resection tissues and DC in the LNs, experienced longer DFS (P = 0.048 and P = 0.024).

CONCLUSION

Immune cells in both pulmonary LNs and the TME collectively influence the remodeling of the NSCLC patient's TME, thus impacting treatment response and prognosis.

Effect of neutrophils on tumor immunity and immunotherapy resistance with underlying mechanisms

Neutrophils are key mediators of the immune response and play essential roles in the development of tumors and immune evasion. Emerging studies indicate that neutrophils also play a critical role in the immunotherapy resistance in cancer. In this review, firstly, we summarize the novel classification and phenotypes of neutrophils and describe the regulatory relationships between neutrophils and tumor metabolism, flora microecology, neuroendocrine and tumor therapy from a new perspective. Secondly, we review the mechanisms by which neutrophils affect drug resistance in tumor immunotherapy from the aspects of the immune microenvironment, tumor antigens, and epigenetics. Finally, we propose several promising strategies for overcoming tumor immunotherapy resistance by targeting neutrophils and provide new research ideas in this area.

Macrophages and T cells in metabolic disorder-associated cancers

Cancer and metabolic disorders have emerged as major global health challenges, reaching epidemic levels in recent decades. Often viewed as separate issues, metabolic disorders are shown by mounting evidence to heighten cancer risk and incidence. The intricacies underlying this connection are still being unraveled and encompass a complex interplay between metabolites, cancer cells and immune cells within the tumour microenvironment (TME). Here, we outline the interplay between metabolic and immune cell dysfunction in the context of three highly prevalent metabolic disorders, namely obesity; two associated liver diseases, metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH); and type 2 diabetes. We focus primarily on macrophages and T cells, the critical roles of which in dictating inflammatory response and immune surveillance in metabolic disorder-associated cancers are widely reported. Moreover, considering the ever-increasing number of patients prescribed with metabolism disorder-altering drugs and diets in recent years, we discuss how these therapies modulate systemic and local immune phenotypes, consequently impacting cancer malignancy. Collectively, unraveling the determinants of metabolic disorder-associated immune landscape and their role in fuelling cancer malignancy will provide a framework essential to therapeutically address these highly prevalent diseases.

Decoding the role of FOXP3 in esophageal cancer: Underlying mechanisms and therapeutic implications

Esophageal cancer is a significant contributor to cancer-related mortality, and its poor prognosis is primarily attributed to the aggressive nature of the tumor and challenges in early detection. Currently, there are no ideal drugs developed for treatment, making it crucial to explore potential biomarkers and molecular targets for esophageal cancer. FOXP3, as a transcription factor and major regulator of regulatory T cells, not only plays a role in promoting or inhibiting tumor development in various types of cancer cells including esophageal cancer cells but also influences the function of Treg cells by regulating the expression of multiple genes. This paper provides an in-depth discussion on the functional properties, regulatory mechanisms, key signaling pathways, as well as the role and potential application of FOXP3 in treating esophageal cancer. Furthermore, it comprehensively analyzes the complex role of this transcription factor within the tumor immune microenvironment with an aim to aid in developing new potential targets for esophageal cancer treatment.

A novel risk score model of lactate metabolism for predicting outcomes and immune signatures in acute myeloid leukemia

Acute myeloid leukemia (AML) is a malignant tumor with high recurrence and refractory rates and low survival rates. Increased glycolysis is characteristic of metabolism in AML blast cells and is also associated with chemotherapy resistance. The purpose of this study was to use gene expression and clinical information from The Cancer Genome Atlas (TCGA) database to identify subtypes of AML associated with lactate metabolism. Two different subtypes linked to lactate metabolism, each with specific immunological features and consequences for prognosis, were identified in this study. Using the TCGA and International Cancer Genome Consortium (GEO) cohorts, a prognostic model composed of genes (LMNA, RETN and HK1) for the prognostic value of the lactate metabolism-related risk score prognostic model was created and validated, suggesting possible therapeutic uses. Additionally, the diagnostic value of the prognostic model genes was explored. LMNA and HK1 were ultimately identified as hub genes, and their roles in AML were determined through immune infiltration, GeneMANIA, GSEA, methylation analysis and single-cell analysis. LMNA was upregulated in AML associating with a poor prognosis while HK1 was downregulated in AML associating with a favorable prognosis. The findings underscore the noteworthy impact of genes linked to lactate metabolism in AML and illustrate the possible therapeutic usefulness of the lactate metabolism-related risk score and the hub lactate metabolism-related genes in guiding AML patients' treatment choices.

Acid affairs in anti-tumour immunity

Metabolic rewiring of cancer cells is one of the hallmarks of cancer. As a consequence, the metabolic landscape of the tumour microenvironment (TME) differs compared to correspondent healthy tissues. Indeed, due to the accumulation of acid metabolites, such as lactate, the pH of the TME is generally acidic with a pH drop that can be as low as 5.6. Disruptions in the acid-base balance and elevated lactate levels can drive malignant progression not only through cell-intrinsic mechanisms but also by impacting the immune response. Generally, acidity and lactate dampen the anti-tumour response of both innate and adaptive immune cells favouring tumour progression and reducing the response to immunotherapy. In this review, we summarize the current knowledge on the functional, metabolic and epigenetic effects of acidity and lactate on the cells of the immune system. In particular, we focus on the role of monocarboxylate transporters (MCTs) and other solute carrier transporters (SLCs) that, by mediating the exchange of lactate (among other metabolites) and bicarbonate, participate in pH regulation and lactate transport in the cancer context. Finally, we discuss advanced approaches to target pH or lactate in the TME to enhance the anti-tumour immune response.

Metabolic gatekeepers: harnessing tumor-derived metabolites to optimize T cell-based immunotherapy efficacy in the tumor microenvironment

The tumor microenvironment (TME) orchestrates a complex interplay between tumor cells and immune cells, crucially modulating the immune response. This review delves into the pivotal role of metabolic reprogramming in the TME, highlighting how tumor-derived metabolites influence T lymphocyte functionality and the efficacy of cancer immunotherapies. Focusing on the diverse roles of these metabolites, we examine how lactate, lipids, amino acids, and other biochemical signals act not only as metabolic byproducts but as regulatory agents that can suppress or potentiate T cell-mediated immunity. By integrating recent findings, we underscore the dual impact of these metabolites on enhancing tumor progression and inhibiting immune surveillance. Furthermore, we propose innovative therapeutic strategies that target metabolic pathways to restore immune function within the TME. The insights provided in this review pave the way for the development of metabolic interventions aimed at enhancing the success of immunotherapies in oncology, offering new hope for precision medicine in the treatment of cancer.

Hydrogel-Mediated Jamming of Exosome Communications That Counter Tumor Adaption in the Tumor Immune Microenvironment

Hypoxia, a common occurrence within solid tumors, can stimulate the dissemination of deceptive tumor exosomes, which function as communicative bridges and orchestrate the recruitment of various supportive cell types for enhanced tumor adaptability in a tumor immune microenvironment. Current nanotechnology provides us intelligent strategies to combat the hypoxic tumor microenvironment. However, once exposed to external stimuli, such as chemotherapy, tumor cells simultaneously release malignant signals to develop tumor migration and immunosuppression, posing challenges to clinical practice. Taking advantage of the membrane-targeting therapeutic strategy, the application of a self-assembled short peptide (PepABS-py), affording hydrogels on tumor cell surfaces, can block exosome dissemination with fiber-like nanostructures and effectively limit the systemic adverse effects of traditional therapeutics. Moreover, PepABS-py can attenuate the hypoxic tumor microenvironment in vivo by carrying an inhibitor of the hypoxic tumor-overexpressed CA IX enzyme, where hypoxia is also a crucial regulator to induce tumor exosomes and mediate intercellular communications within the immune system. Herein, its application on jamming exosome communications can target the T cell-related signaling pathway by regulating microRNAs in exosome cargoes and ultimately enhances CD8+ T cell infiltration and alleviates inflammatory monocytes at metastasis sites. Collectively, with the capability of blocking exosome dissemination, PepABS-py can be applied as a promising tumor membrane-targeting therapeutic tool to counter tumor adaption within an immune microenvironment and further advance traditional chemotherapy.

JAML overexpressed in colorectal cancer promotes tumour proliferation by activating the PI3K-AKT-mTOR signalling pathway

The expression and biological function of junctional adhesion molecule-like protein (JAML) in colorectal cancer (CRC) remain unclear. Paraffin tissue samples from 50 cases of CRC were collected to determine the expression of JAML. JAML was overexpressed or knock-down in CRC cells to evaluated the proliferation, migration and invasion in vitro and in vivo. Western-blot and others were applied to explore the mechanisms. The study showed that JAML was highly expressed within cancer tissues in 50% (25/50) of patients with CRC, and was correlated with higher TNM stage (p < 0.05). Patients of JAML-high group had poorer overall survival compared to JAML-low group (p = 0.0362, HR = 0.4295, 95% CI of 0.1908-0.9667). The tumour infiltrating lymphocytes (TILs) was lower in the JAML-high group than in the JAML-low group (p < 0.05). Overexpression of JAML promoted the proliferation, migration, and invasion of CRC by activating the PI3K-AKT-mTOR signalling pathway both in vitro and in vivo. TILs were reduced in JAML-high tumour tissues by decreasing chemokines such as CCL20 and CXCL9/10/11. Our study identified JAML, a potentially ideal target that is specifically highly expressed in CRC tissues, which promoted tumour proliferation, impaired T-lymphocytes infiltration, provided a promising therapeutic strategy for patients with CRC.

Cold and hot tumors: from molecular mechanisms to targeted therapy

Immunotherapy has made significant strides in cancer treatment, particularly through immune checkpoint blockade (ICB), which has shown notable clinical benefits across various tumor types. Despite the transformative impact of ICB treatment in cancer therapy, only a minority of patients exhibit a positive response to it. In patients with solid tumors, those who respond well to ICB treatment typically demonstrate an active immune profile referred to as the "hot" (immune-inflamed) phenotype. On the other hand, non-responsive patients may exhibit a distinct "cold" (immune-desert) phenotype, differing from the features of "hot" tumors. Additionally, there is a more nuanced "excluded" immune phenotype, positioned between the "cold" and "hot" categories, known as the immune "excluded" type. Effective differentiation between "cold" and "hot" tumors, and understanding tumor intrinsic factors, immune characteristics, TME, and external factors are critical for predicting tumor response and treatment results. It is widely accepted that ICB therapy exerts a more profound effect on "hot" tumors, with limited efficacy against "cold" or "altered" tumors, necessitating combinations with other therapeutic modalities to enhance immune cell infiltration into tumor tissue and convert "cold" or "altered" tumors into "hot" ones. Therefore, aligning with the traits of "cold" and "hot" tumors, this review systematically delineates the respective immune characteristics, influencing factors, and extensively discusses varied treatment approaches and drug targets based on "cold" and "hot" tumors to assess clinical efficacy.

How lactate affects immune strategies in lymphoma

Tumor cells undergo metabolic reprogramming through shared pathways, resulting in a hypoxic, acidic, and highly permeable internal tumor microenvironment (TME). Lactate, once only regarded as a waste product of glycolysis, has an inseparable dual role with tumor immunity. It can not only provide a carbon source for immune cells to enhance immunity but also help the immune escape through a variety of ways. Lymphoma also depends on the proliferation signal of TME. This review focuses on the dynamic process of lactate metabolism and immune function changes in lymphoma and aims to comprehensively summarize and explore which genes, transcription factors, and pathways affect the biological changes and functions of immune cells. To deeply understand the complex and multifaceted role of lactate metabolism and immunity in lymphoma, the combination of lactate targeted therapy and classical immunotherapy will be a promising development direction in the future.

Balancing Tumor Immunotherapy and Immune-Related Adverse Events: Unveiling the Key Regulators

Tumor immunotherapy has emerged as a promising approach in cancer treatment in recent years, offering vast potential. This method primarily involves targeting and inhibiting the suppressive checkpoints present in different immune cells to enhance their activation, ultimately leading to tumor regression. However, tumor cells exploit the surrounding immune cells and tissues to establish a tumor microenvironment (TME) that supports their survival and growth. Within the TME, the efficacy of effector immune cells is compromised, as tumor cells exploit inhibitory immune cells to suppress their function. Furthermore, certain immune cells can be co-opted by tumor cells to facilitate tumor growth. While significantly enhancing the body's tumor immunity can lead to tumor regression, it can also result in severe toxic side effects and an inflammatory factor storm. As a consequence, patients often discontinue treatment due to immune-related adverse events (irAEs) or, in extreme cases, succumb to toxic side effects before experiencing tumor regression. In this analysis, we examined several remission regimens for irAEs, each with its own drawbacks, including toxic side effects or suppression of tumor immunotherapy, which is undesirable. A recent research study, specifically aimed at downregulating intestinal epithelial barrier permeability, has shown promising results in reducing the severity of inflammatory bowel disease (IBD) while preserving immune function. This approach effectively reduces the severity of IBD without compromising the levels of TNF-α and IFN-γ, which are crucial for maintaining the efficacy of tumor immunotherapy. Based on the substantial similarities between IBD and ICI colitis (combo immune checkpoint inhibitors-induced colitis), this review proposes that targeting epithelial cells represents a crucial research direction for mitigating irAEs in the future.