Metabolic Reprogramming of Immune Cells in Cancer Progression

MCC in the spotlight: Its dual role in signal regulation and oncogenesis

The mutated in colorectal cancer (MCC) gene is closely associated with the onset and progression of colorectal cancer. MCC plays a critical role in regulating the cell cycle and various signaling pathways and is recognized to inhibit cancer cell proliferation via the β-catenin signaling pathway. β-catenin is a key component of the WNT signaling pathway that influences cell growth, differentiation, survival, and migration, thereby positioning MCC as an important tumor suppressor. Notably, MCC has also been implicated in other cancer types, including lung, liver, and brain cancers. However, the precise mechanisms by which MCC functions in these malignancies remain inadequately understood. Comprehensive investigations into the interactions among MCC, various signaling pathways, and metabolic processes are essential for uncovering the molecular mechanisms of cancer and the pathological features characteristic of different cancer stages. This review presents the structural characteristics of MCC and its cell growth regulation mechanisms and functional roles within tissues, with the aims of enhancing our understanding of the role of MCC in cancer biology and highlighting potential therapeutic strategies targeting this gene.

Age- and diet-instructed metabolic rewiring of the tumor-immune microenvironment

The tumor-immune microenvironment (TIME) plays a critical role in tumor development and metastasis, as it influences the evolution of tumor cells and fosters an immunosuppressive state by intervening the metabolic reprogramming of infiltrating immune cells. Aging and diet significantly impact the metabolic reprogramming of the TIME, contributing to cancer progression and immune evasion. With aging, immune cell function declines, leading to a proinflammatory state and metabolic alterations such as increased oxidative stress and mitochondrial dysfunction, which compromise antitumor immunity. Similarly, dietary factors, particularly high-fat and high-sugar diets, promote metabolic shifts, creating a permissive TIME by fostering tumor-supportive immune cell phenotypes while impairing the tumoricidal activity of immune cells. In contrast, dietary restrictions have been shown to restore immune function by modulating metabolism and enhancing antitumor immune responses. Here, we discuss the intricate interplay between aging, diet, and metabolic reprogramming in shaping the TIME, with a particular focus on T cells, and highlight therapeutic strategies targeting these pathways to empower antitumor immunity.

Dysregulation of the SREBP pathway is associated with poor prognosis and serves as a potential biomarker for the diagnosis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a severe disease associated with a poor prognosis. The role of aberrant lipid metabolism in the development and progression of HCC necessitates detailed characterization. Sterol regulatory element‑binding proteins (SREBPs), pivotal transcription factors governing lipogenesis, are central to this process. The present study aimed to assess the regulation of HCC by the SREBP signaling pathway, examining the expression levels of genes in this pathway, the clinical implications and its prognostic value using the Kaplan‑Meier method. Pearson's correlation coefficient was used to identify the co‑expression of SREBP pathway genes in HCC. Genomic analysis examined the frequency of TP53 mutations in groups with and without SREBP pathway alterations. In addition, small interfering RNAs targeting genes of the SREBP pathway were transfected into Huh‑7 and HCC‑LM3 cell lines. Subsequently, Cell Counting Kit‑8 and Transwell assays were carried out to evaluate the viability and invasion of these cells. Reverse transcription‑quantitative PCR and western blotting were performed to investigate the expression of TP53 in response to silencing of SREBP pathway genes. Dysregulation of SREBP pathway genes was detected in HCC tissues compared with in normal liver tissues, and predicted a poor prognosis. Silencing these genes reduced the viability and invasion of HCC cells. Furthermore, abnormal SREBP pathway gene expression was associated with poor survival rates, vascular invasion, advanced tumor stage and an increased incidence of TP53 mutations. By contrast, knockdown of SREBP pathway genes decreased mutant TP53 expression at both the mRNA and protein levels in HCC cells. The findings of the present study suggested that SREBP pathway genes could serve as promising prognostic biomarkers for HCC. The combined analysis of individual gene expression levels offers offer novel insights into the pathogenesis and progression of HCC.

RETRACTED: MiR-375 impairs breast cancer cell stemness by targeting the KLF5/G6PD signaling axis

Recurrence of breast cancer may be due to the presence of breast cancer stem cells (BCSC). Abnormal tumor cell growth is closely associated with increased reactive oxygen species (ROS) and disruption of redox homeostasis, and BCSCs exhibit low levels of ROS. The detailed mechanism between the low levels of ROS in BCSCs and their maintenance of stemness characteristics has not been reported. A growing number of studies have shown that tumor development is often accompanied by metabolic reprogramming, which is an important hallmark of tumor cells. As the first rate-limiting enzyme of pentose phosphate pathway (PPP), the expression of G6PD is precisely regulated in tumor cells, and there is a certain correlation between PPP and BCSCs. MiR-375 has been shown to inhibit stem cell-like properties in breast cancer, but the exact mechanism is not clear. Here, KLF5, as a transcription factor, was identified to bind to the promoter of G6PD to promote its expression, whereas miR-375 inhibited the expression of KLF5 by binding to the 3'UTR region of KLF5 mRNA and thus reduced the expression of G6PD expression, inhibits PPP to reduce NADPH, and increases ROS levels in breast cancer cells, thereby weakening breast cancer cell stemness. Our study reveals the specific mechanism by which miR-375 targets the KLF5/G6PD signaling axis to diminish the stemness of breast cancer cells, providing a therapeutic strategy against BCSCs.

SENP1-Sirt3 axis promotes cholesterol biosynthesis in tumor-associated macrophages to suppress anti-tumor immunity

Tumor-associated macrophages (TAMs) play a multifaceted role in the tumor microenvironment, notably by suppressing antitumor immune responses through immunosuppressive mechanisms. TAMs secrete a range of cytokines that simultaneously inhibit T cell function and foster a microenvironment that supports tumor progression and dissemination. Our study has delved into the intricate relationship between the metabolic reprogramming of TAMs and their impact on tumor progression. Mitochondrial metabolic reprogramming mediated by the SENP1-Sirt3 axis altered the dynamics and activity of tumor-infiltrating immune cells, including macrophages and CD8+ T lymphocytes. SENP1-Sirt3 axis increases the level of acetyl-CoA in macrophage mitochondria, which in turn promotes cholesterol biosynthesis in macrophages. The upregulation of cholesterol synthesis is a key factor in driving macrophage polarization towards the immunosuppressive M2 phenotype, which in turn supports tumor development. Notably, increased cholesterol levels contributed to a reduction in the number and activity of CD8+ T cells, which are essential for mounting an effective immune response against cancer cells. These findings suggest that targeting cholesterol biosynthesis in TAMs may be a promising strategy for cancer immunotherapy. SIGNIFICANCE: Activation of the SENP1-Sirt3 axis initiates mitochondrial metabolic reprogramming in tumor-associated macrophages (TAMs), leading to enhanced cholesterol and acetyl-CoA production, M2 macrophage polarization, and impaired CD8+ T cell anti-tumor responses.

Nutritional strategies in oncology: The role of dietary patterns in modulating tumor progression and treatment response

Dietary interventions can influence tumor growth by restricting tumor-specific nutritional requirements, altering the nutrient availability in the tumor microenvironment, or enhancing the cytotoxicity of anticancer drugs. Metabolic reprogramming of tumor cells, as a significant hallmark of tumor progression, has a profound impact on immune regulation, severely hindering tumor eradication. Dietary interventions can modify tumor metabolic processes to some extent, thereby further improving the efficacy of tumor treatment. In this review, we emphasize the impact of dietary patterns on tumor progression. By exploring the metabolic differences of nutrients in normal cells versus cancer cells, we further clarify how dietary patterns influence cancer treatment. We also discuss the effects of dietary patterns on traditional treatments such as immunotherapy, chemotherapy, radiotherapy, and the gut microbiome, thereby underscoring the importance of precision nutrition.

Metabolic interplays between the tumour and the host shape the tumour macroenvironment

Metabolic reprogramming of cancer cells and the tumour microenvironment are pivotal characteristics of cancers, and studying these processes offer insights and avenues for cancer diagnostics and therapeutics. Recent advancements have underscored the impact of host systemic features, termed macroenvironment, on facilitating cancer progression. During tumorigenesis, these inherent features of the host, such as germline genetics, immune profile and the metabolic status, influence how the body responds to cancer. In parallel, as cancer grows, it induces systemic effects beyond the primary tumour site and affects the macroenvironment, for example, through inflammation, the metabolic end-stage syndrome of cachexia, and metabolic dysregulation. Therefore, understanding the intricate metabolic interplay between the tumour and the host is a growing frontier in advancing cancer diagnosis and therapy. In this Review, we explore the specific contribution of the metabolic fitness of the host to cancer initiation, progression and response to therapy. We then delineate the complex metabolic crosstalk between the tumour, the microenvironment and the host, which promotes disease progression to metastasis and cachexia. The metabolic relationships among the host, cancer pathogenesis and the consequent responsive systemic manifestations during cancer progression provide new perspectives for mechanistic cancer therapy and improved management of patients with cancer.

Bifidobacterium longum subsp. longum XZ01 delays the progression of colon cancer in mice through the interaction between the microbial spatial distribution and tumour immunity

Studies have shown that the colonisation of active microorganisms is more conducive to the development of tumour immunotherapy, but intuitive evidence regarding shaping of the tumour immune microenvironment is lacking. In this study, we used Bifidobacterium longum subsp. longum (XZ01) to intervene in a colon cancer mouse model and found that its mechanism may be related to the interaction between the spatial distribution of microorganisms and tumour immunity. Through the visualisation method we established, for the first time, we showed that harmful active bacteria such as Streptococcus and Rhodococcus specifically accumulate in the middle and upper layers of tumour tissue. These bacteria likely participate in signalling pathways that affect macrophages by directly contacting or invading the macrophages, leading to a nondifferentiated state in macrophages and the loss of some immune functions. Furthermore, the accumulation of Streptococcus and Rhodococcus fragments in the deep layer of tumour tissue likely upregulates the expression of IL-10 in tumour tissue and inhibits other immune cells, such as CD8+ T cells, DC and NK cells. In contrast, XZ01 can specifically compete for the growth sites of Streptococcus and Rhodococcus in the middle and upper layers of tumour tissue and probably protects macrophages from being invaded by harmful bacteria. XZ01 directly regulates the polarisation of M0 macrophages towards the M1 phenotype by upregulating IFN-γ, thus activating tumour immunity to inhibit the growth of tumour cells. This study revealed that the influence of active microorganisms on the tumour immune microenvironment is crucial for effective immunotherapy intervention, potentially offering new targets for improving patient prognosis.

Single-cell sequencing and spatial transcriptomics reveal the evolution of glucose metabolism in hepatocellular carcinoma and identify G6PD as a potential therapeutic target

Background

Glucose metabolism reprogramming provides significant insights into the development and progression of malignant tumors. This study aims to explore the temporal-spatial evolution of the glucose metabolism in HCC using single-cell sequencing and spatial transcriptomics (ST), and validates G6PD as a potential therapeutic target for HCC.

Methods

We collected single-cell sequencing data from 7 HCC and adjacent non-cancerous tissues from the GSE149614 database, and ST data from 4 HCC tissues from the HRA000437 database. Pseudotime analysis was performed on the single-cell data, while ST data was used to analyze spatial metabolic activity. High-throughput sequencing and experiments, including wound healing, CCK-8, and transwell assays, were conducted to validate the role and regulatory mechanisms of G6PD in HCC.

Results

Our study identified a progressive upregulation of PPP-related genes during tumorigenesis. ST analysis revealed elevated PPP metabolic scores in the central and intermediate tumor regions compared to the peripheral zones. High-throughput sequencing and experimental validation further suggested that G6PD-mediated regulation of HCC cell proliferation, migration, and invasion is likely associated with glutathione metabolism and ROS production. Finally, Cox regression analysis cofirmed G6PD as an independent prognostic factor for overall survival in HCC patients.

Conclusion

Our study provides novel insights into the changes in glucose metabolism in HCC from both temporal and spatial perspectives. We experimentally demonstrated that G6PD regulates proliferation, migration, and invasion in HCC and propose G6PD as a prognostic marker and therapeutic metabolic target for the HCC.

Restoring immune tolerance in pre-RA: immunometabolic dialogue between gut microbiota and regulatory T cells

Rheumatoid arthritis (RA) is a complex chronic autoimmune disease that remains incurable for most patients. With advances in our understanding of the disease's natural history, the concept of pre-RA has emerged as a window of opportunity to intervene before irreversible joint damage occurs. Numerous studies have indicated that the key step driving autoimmunity in early pre-RA lies at an extra-articular site, which is closely related to the regulatory T (Treg) cell-established immune tolerance to the gut microbiota. The intricate immunometabolic crosstalk between Treg cells and the gut microbiota is beginning to be understood, with the re-recognition of Treg cells as metabolic sensors in recent years. In the future, deciphering their immunometabolic dialogue may help to elucidate the underlying mechanisms of pre-RA. Identifying novel biological pathways in the pre-RA stage will bring insights into restoring immune tolerance, thereby potentially curing or preventing the onset of RA.

Heterogeneous cellular responses to hyperthermia support combined intraperitoneal hyperthermic immunotherapy for ovarian cancer mouse models

The benefit of hyperthermic intraperitoneal chemotherapy (HIPEC) in ovarian cancer remains controversial, hindering the development of rational combination therapies based on hyperthermia (HT). This study reports the preliminary results of the neoadjuvant HIPEC (NHIPEC) trial (ChiCTR2000038173), demonstrating enhanced tumor response in high-grade serous ovarian cancer with NHIPEC. Through single-cell RNA sequencing analysis, we identified both homogeneous and heterogeneous cellular responses to HT within the tumor and microenvironment. Epithelial-mesenchymal transition-activated tumor cells and matrix metallopeptidase 11 (MMP-11)+ cancer-associated fibroblasts (CAFs) exhibited greater reductions and higher sensitivity to HT. CUT&Tag and RNA sequencing integration unveiled the differential binding programs and transcriptional regulatory mechanisms of HSF1 under normothermia (NT) and HT in tumor cells and CAFs. Furthermore, HT ameliorated the immunosuppressive tumor microenvironment, and in vivo mouse models confirmed the combined antitumor effects of HT and programmed cell death ligand 1 blockade. These findings provide an innovative strategy for rational combination therapy with HT in ovarian cancer.

Changes in L-phenylalanine concentration reflect and predict response to anti-PD-1 treatment combined with chemotherapy in patients with non-small cell lung cancer

Chemotherapy combined with checkpoint blockade antibodies targeting programmed cell death protein (PD-1) has achieved remarkable success in non-small cell lung cancer. However, few patients benefit from long-term treatment. Therefore, biomarkers capable of guiding the optimal therapeutic selection and reducing unnecessary toxicity are of pressing importance. In our research, we gathered serial blood samples from two groups of non-small cell lung cancer patients: 49 patients received a combination of therapies, and 34 patients went under chemotherapy alone. Utilizing non-targeted metabolomic analysis, we examined different metabolites' disparity. Among the lot, L-phenylalanine emerged as a significant prognostic marker in the combination treatment of non-small cell lung cancer patients, interestingly absent in patients under sole chemotherapy. The reduced ratio of L-phenylalanine concentration (two-cycle treatment vs. pre-treatment) was associated with improved progression-free survival (hazard ratio = 1.8000, 95% confidence interval: 0.8566‒3.7820, p < 0.0001) and overall survival (hazard ratio = 1.583, 95% confidence interval: 0.7416‒3.3800, p < 0.005). We further recruited two validation cohorts (cohort 1: 40 patients and cohort 2: 30 patients) to validate the sensitivity and specificity of L-phenylalanine prediction. Our results demonstrate that a model based on L-phenylalanine variations could serve as an early risk-assessment tool for non-small cell lung cancer patients undergoing treatment, potentially facilitating strategic clinical decision-making.

Promotion of triple negative breast cancer immunotherapy by combining bioactive radicals with immune checkpoint blockade

Although immunotherapy has revolutionized clinical cancer treatment, the efficacy is limited due to the lack of tumor-associated antigens (TAAs) and the presence of compensatory immune checkpoints. To overcome the deficiency, a nano-system loaded with ozone and CD47 inhibitor RRx-001 is designed and synthesized. Upon irradiation, reactive oxygen species (ROS) generated from ozone reacts with nitric oxide (NO) metabolized from RRx-001 to form reactive nitrogen species (RNS), which presents a much stronger cell-killing ability than ROS. Molecular mechanism studies further reveal that RNS induce extensive immunogenic cell death (ICD). The released TAAs promote infiltration of cytotoxic T lymphocytes, which provides the basis for immune checkpoint blockade (ICB) therapy. Meanwhile, RRx-001 carried by the nanoparticles and the produced radicals repolarize M2-type tumor-associated macrophages (TAMs) into the anti-tumor M1-type, consequently reversing the immunosuppressive tumor microenvironment (TME). In a xenograft triple-negative breast cancer (TNBC) animal model, O3-001@lipo (liposome enwrapping O3 and RRx-001) plus irradiation shows a significant anti-tumor efficacy by improving cytotoxic lymphocyte infiltration and regulating immunosuppressive TME. In summary, the O3-001@lipo nano-system triggered by irradiation potently improves the efficacy of immunotherapy by introducing strong cytotoxic RNS, which not only enriches the toolbox of ICD inducer but also provides a strategy of treatment for immune deficient tumor. STATEMENT OF SIGNIFICANCE: This study introduces a nano-system that leverages ozone and RRx-001 in the presence of X-ray irradiation to generate reactive nitrogen species, enhancing immunogenic cell death and promoting T-lymphocyte infiltration in triple-negative breast cancer, addressing a significant unmet need in the field. The scientific contribution is the development of a clinically translatable nano-system that not only induces ICD but also reshapes the tumor microenvironment, which is expected to have a profound impact on the readership in pharmaceutics, material science, and nano-bio interaction, particularly for those interested in advanced immune therapy approaches.

N6-methyladenosine modification of 3'tRF-AlaAGC impairs PD-1 blockade efficacy by promoting lactic acid accumulation in the tumor microenvironment of gastric carcinoma

The balance between CD8+ T cells and regulatory T (Treg) cells in the tumor microenvironment (TME) plays a crucial role in the immune checkpoint inhibition (ICI) therapy in gastric carcinoma (GC). However, related factors leading to the disturbance of TME and resistance to ICI therapy remain unknown. In this study, we applied N6-methyladenosine (m6A) small RNA Epitranscriptomic Microarray and screened out 3'tRF-AlaAGC based on its highest differential expression level and lowest inter-group variance. N6-methyladenosine modification significantly enhanced the stability of 3'tRF-AlaAGC, which strengthened glycolysis and lactic acid (LA) production in GC cells by binding to PTBP1 (Polypyrimidine Tract Binding Protein 1). In the peritoneal GC implantation model established in huPBMC-NCG mice, 3'tRF-AlaAGC significantly increased the proportion of PD1+ Treg cells. Furthermore, in high-LA environments driven by glucose consumption of GC cells, Treg cells actively uptake LA through MCT1, facilitating NFAT1 translocation into the nucleus and enhancing PD1 expression, whereas PD1 expression by effector T cell is diminished. Meanwhile, T cell suppression assays were performed under low-LA or high-LA conditions, and the proliferation of CD8+ T cells was dampened by adding Sintilimab in a high-LA but not in a low-LA environment, suggesting the preferential activation of PD1+ Treg cell. These findings deciphered the complexities of the immune microenvironment in GC, providing prospects for identifying robust biomarkers that could improve the evaluation of therapeutic effectiveness and prognosis in immune therapy for GC.

Tumor-Targeted Glutamine Metabolism Blocker Synergizes with TiO2-Au Janus Nanoparticles for Enhanced Sono-Metabolic Antitumor Therapy

Sonodynamic therapy (SDT) is a promising therapeutic modality known for its non-invasiveness, temporal-spatial controllability, and deeper tissue penetration. However, the SDT treatment efficacy is still hampered by the scarcity of ideal sonosensitizers and complex tumor microenvironment (TME). To address these challenges, a sono-metabolic nano-composite (TiO2-Au@DON) using the metabolic reprogramming prodrugs of 6-Diazo-5-oxo-l-norleucine (DON) grafted on TiO2-Au Janus nanoparticles (NPs) is fabricated. The coupling of TiO2 and gold in the TiO2-Au@DON effectively prevents the fast recombination of excited electrons and holes under ultrasound irradiation. The result is the generation of higher levels of both type I and II reactive oxygen species (ROS) compared to pure TiO2, which helps overcome the limitations of SDT in the hypoxic TME. Furthermore, the TiO2-Au Janus NPs act as nano-carriers, delivering DON prodrugs to the tumor site. The released DON can disrupt nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) and tumor redox homeostasis by reprogramming the metabolic pathways while it intensifies the activities of immune cells. This metabolic disruption amplifies SDT-mediated oxidative stress, resulting in the increase of tumor sensitivity to ROS through TiO2-Au@DON-integrated synergistic effects of SDT and glutamine reprogramming strategies. This increased sensitivity ultimately induces robust immunogenic cell death (ICD), enhancing antitumor therapeutic efficacy and remodeling the tumor's immunosuppressive microenvironment.

FOXP3 Transcriptionally Activates Fatty Acid Scavenger Receptor CD36 in Tumour-Induced Treg Cells

The host immune system is adapted in a variety of ways by tumour microenvironment and growing tumour interacts to promote immune escape. One of these adaptations is manipulating the metabolic processes of cells in the tumour microenvironment. The growing tumour aggressively utilise glucose, its primary energy source available in tumour site, and produce lactate by Warburg effect. In such a hostile environment, tumour-infiltrating immune cells are unable to survive metabolically. Tumour-infiltrating CD4+ Treg cells, on the other hand, adapted to an alternative energy-generating system, switching from the highly-competitive glucose to the fatty-acid metabolic pathway, by down-regulating glucose-metabolising genes and up-regulating fatty-acid metabolising genes. Tregs with high-levels of the fatty acid scavenger receptor CD36, a key component of the fatty-acid metabolic pathway, aided this metabolic shift. Treg cell formation was hampered when the fatty-acid metabolic pathway was disrupted, showing that it is necessary for Treg cell development. FOXP3, the Treg lineage-specific transcription factor, regulates fatty-acid metabolism by inducing CD36 transcription. A high-fat diet enhanced Treg development while suppressing anti-tumour immunity, whereas a low-fat diet suppressed Treg development. The altered metabolism of tumour-infiltrating Treg cells enables their rapid generation and survival in the hostile tumour microenvironment, aiding cancer progression. Fascinatingly, mice fed with a low-fat diet showed a positive prognosis with chemotherapy than mice fed with a high-fat diet. Thus, a maximum efficacy of chemotherapy might be achieved by altering diet composition during chemotherapy, providing a promising indication for future cancer treatment.

Fructose-1,6-bisphosphatase 1 in cancer: Dual roles, mechanistic insights, and therapeutic potential - A comprehensive review

Fructose-1,6-bisphosphatase 1 (FBP1) is a key gluconeogenic enzyme that plays complex and context-dependent roles in cancer biology. This review comprehensively examines FBP1's dual functions as both a tumor suppressor and an oncogene across various cancer types. In many cancers, such as hepatocellular carcinoma, clear cell renal cell carcinoma, and lung cancer, downregulation of FBP1 contributes to tumor progression through metabolic reprogramming, promoting glycolysis, and altering the tumor microenvironment. Conversely, in certain contexts like breast and prostate cancers, FBP1 overexpression is associated with tumor promotion, indicating its oncogenic potential. The review explores FBP1's interactions with immune cells within the tumor microenvironment, influencing immune surveillance and tumor immune escape mechanisms. Additionally, FBP1 emerges as a promising diagnostic and prognostic biomarker, with expression levels correlating with patient outcomes in multiple cancers. Future therapeutic strategies targeting FBP1 are discussed, including inhibitors, activators, epigenetic modulation, and combination therapies, while addressing the challenges posed by its dual nature. Understanding the multifaceted roles of FBP1 offers valuable insights into cancer metabolism and opens avenues for personalized therapeutic interventions.

Unveiling Novel Targets in Lung Tumors for Enhanced Radiotherapy Efficacy: A Comprehensive Review

Radiotherapy is a cornerstone of lung cancer management, though its efficacy is frequently undermined by intrinsic and acquired radioresistance. This review examines the complexity of lung tumors, highlighting their potential as a reservoir of novel targets for radiosensitization. Ionizing radiation (IR) primarily exerts its effects through oxidative damage and DNA double-strand breaks (DSBs). Lung cancer cells, however, develop mutations that enhance DNA damage response (DDR) and suppress cell death pathways. Additionally, interactions between tumor cells and tumor microenvironment (TME) components-including immune cells, stromal cells, and molecular mediators such as cytokines, chemokines, and growth factors-contribute to resistance against IR. Understanding these intricate relationships reveals potential targets to improve radiotherapy outcomes. Promising targets include DDR pathways, immunosuppressive cells and molecules, hypoxia, proangiogenic mediators, and other key signaling pathways. This review discusses emerging strategies, such as combining radiotherapy with immunomodulators, hypoxia and proangiogenic inhibitors, DDR-targeting agents, and other innovative approaches. By offering a comprehensive analysis of the lung TME, this review underscores opportunities to enhance radiotherapy effectiveness through targeted radiosensitization strategies.

Cancer stem cells and niches: challenges in immunotherapy resistance

Cancer stem cells (CSCs) are central to tumor progression, metastasis, immune evasion, and therapeutic resistance. Characterized by remarkable self-renewal and adaptability, CSCs can transition dynamically between stem-like and differentiated states in response to external stimuli, a process termed "CSC plasticity." This adaptability underpins their resilience to therapies, including immune checkpoint inhibitors and adoptive cell therapies (ACT). Beyond intrinsic properties, CSCs reside in a specialized microenvironment-the CSC niche-which provides immune-privileged protection, sustains their stemness, and fosters immune suppression. This review highlights the critical role of CSCs and their niche in driving immunotherapy resistance, emphasizing the need for integrative approaches to overcome these challenges.

Invasion and metastasis in cancer: molecular insights and therapeutic targets

The progression of malignant tumors leads to the development of secondary tumors in various organs, including bones, the brain, liver, and lungs. This metastatic process severely impacts the prognosis of patients, significantly affecting their quality of life and survival rates. Research efforts have consistently focused on the intricate mechanisms underlying this process and the corresponding clinical management strategies. Consequently, a comprehensive understanding of the biological foundations of tumor metastasis, identification of pivotal signaling pathways, and systematic evaluation of existing and emerging therapeutic strategies are paramount to enhancing the overall diagnostic and treatment capabilities for metastatic tumors. However, current research is primarily focused on metastasis within specific cancer types, leaving significant gaps in our understanding of the complex metastatic cascade, organ-specific tropism mechanisms, and the development of targeted treatments. In this study, we examine the sequential processes of tumor metastasis, elucidate the underlying mechanisms driving organ-tropic metastasis, and systematically analyze therapeutic strategies for metastatic tumors, including those tailored to specific organ involvement. Subsequently, we synthesize the most recent advances in emerging therapeutic technologies for tumor metastasis and analyze the challenges and opportunities encountered in clinical research pertaining to bone metastasis. Our objective is to offer insights that can inform future research and clinical practice in this crucial field.

Breast cancer: pathogenesis and treatments

Breast cancer, characterized by unique epidemiological patterns and significant heterogeneity, remains one of the leading causes of malignancy-related deaths in women. The increasingly nuanced molecular subtypes of breast cancer have enhanced the comprehension and precision treatment of this disease. The mechanisms of tumorigenesis and progression of breast cancer have been central to scientific research, with investigations spanning various perspectives such as tumor stemness, intra-tumoral microbiota, and circadian rhythms. Technological advancements, particularly those integrated with artificial intelligence, have significantly improved the accuracy of breast cancer detection and diagnosis. The emergence of novel therapeutic concepts and drugs represents a paradigm shift towards personalized medicine. Evidence suggests that optimal diagnosis and treatment models tailored to individual patient risk and expected subtypes are crucial, supporting the era of precision oncology for breast cancer. Despite the rapid advancements in oncology and the increasing emphasis on the clinical precision treatment of breast cancer, a comprehensive update and summary of the panoramic knowledge related to this disease are needed. In this review, we provide a thorough overview of the global status of breast cancer, including its epidemiology, risk factors, pathophysiology, and molecular subtyping. Additionally, we elaborate on the latest research into mechanisms contributing to breast cancer progression, emerging treatment strategies, and long-term patient management. This review offers valuable insights into the latest advancements in Breast Cancer Research, thereby facilitating future progress in both basic research and clinical application.

Post-COVID-19 Condition Prediction in Hospitalised Cancer Patients: A Machine Learning-Based Approach

BACKGROUND

The COVID-19 pandemic has led to widespread long-term complications, known as post-COVID conditions (PCC), particularly affecting vulnerable populations such as cancer patients. This study aims to predict the incidence of PCC in hospitalised cancer patients using the data from a longitudinal cohort study conducted in four major university hospitals in Moscow, Russia.

METHODS

Clinical data have been collected during the acute phase and follow-ups at 6 and 12 months post-discharge. A total of 49 clinical features were evaluated, and machine learning classifiers including logistic regression, random forest, support vector machine (SVM), k-nearest neighbours (KNN), and neural network were applied to predict PCC.

RESULTS

Model performance was assessed using the area under the receiver operating characteristic curve (AUC), sensitivity, and specificity. KNN demonstrated the highest predictive performance, with an AUC of 0.80, sensitivity of 0.73, and specificity of 0.69. Severe COVID-19 and pre-existing comorbidities were significant predictors of PCC.

CONCLUSIONS

Machine learning models, particularly KNN, showed some promise in predicting PCC in cancer patients, offering the potential for early intervention and personalised care. These findings emphasise the importance of long-term monitoring for cancer patients recovering from COVID-19 to mitigate PCC impact.

Molecular Mechanisms of Immune Regulation: A Review

BACKGROUND

The immune system must carefully balance fighting pathogens with minimization of inflammation and avoidance of autoimmune responses. Over the past ten years, researchers have extensively studied the mechanisms regulating this delicate balance. Comprehending these mechanisms is essential for developing treatments for inflammatory conditions.

AIM

This review aims to synthesize knowledge of immunoregulatory processes published from 2014-2024 and to highlight discoveries that provide fresh perspectives on this complex balance.

METHODS

The keywords "molecular mechanisms", "immune regulation", "immune signaling pathways", and "immune homeostasis" were used to search PubMed for articles published between 2014 and 2024, with a preference for articles published in the past three years.

RESULTS

Recent research has pinpointed the impact of factors such as cytokine signaling, T-cell regulation, epigenetic regulation, and immunometabolism on immune function.

DISCUSSION

New research highlights the intricate interactions between the immune system and other molecular elements. A key area of interest is the impact of non-coding RNAs and metabolic pathways on the regulation of immune responses.

CONCLUSIONS

Exploring the mechanisms by which the immune system is regulated will provide new avenues for developing treatments to address autoimmune and inflammatory conditions.

A comprehensive analysis of the pyruvate kinase M1/2 (PKM) in human cancer

BACKGROUND

Pyruvate Kinase Muscle Isozyme (PKM), as a member of the pyruvate kinase, is a key enzyme in glycolysis. Numerous tumors have demonstrated its oncogenic properties. There is, however, no pan-carcinogenic analysis for PKM.

METHODS

A thorough analysis of PKM across various types of cancer was carried out using bioinformatics resources like The National Cancer Institute's Clinical Proteomic Tumor Analysis Consortium (CPTAC) and The Cancer Genome Atlas (TCGA) database. This study involved analyzing the role of PKM in 33 various types of cancers, along with investigating gene expressions, survival rates, clinical importance, genetic changes, immune system presence, and related signaling pathways. Furthermore, we evaluated the effects of PKM knockdown on human colon carcinoma, and glioblastoma cell lines by in vitro experimentation.

RESULTS

In most tumors, PKM expression was markedly increased and was associated with unfavorable overall survival (OS) in certain individuals. In addition, infiltration of macrophages was associated with PKM expression in various tumors. PKM was linked to glycolysis/gluconeogenesis, HIF-1 signaling, carbon metabolism, and NADPH regeneration in a mechanistic manner. Additionally, cell experiments showed that the knockdown of PKM could reduce the proliferation and migration abilities while promoting the apoptosis of Caco-2, and U-87 MG cells.

CONCLUSION

PKM controls immune cell infiltration, impacts patient outcomes in various types of cancer, and plays an essential role in proliferation and migration in some tumor cells by affecting glycometabolism. The PKM molecule may serve as a potential prognostic biomarker and therapeutic target for human cancers.

Anti-Tumor Strategies Targeting Nutritional Deprivation: Challenges and Opportunities

Higher and richer nutrient requirements are typical features that distinguish tumor cells from AU: cells, ensuring adequate substrates and energy sources for tumor cell proliferation and migration. Therefore, nutrient deprivation strategies based on targeted technologies can induce impaired cell viability in tumor cells, which are more sensitive than normal cells. In this review, nutrients that are required by tumor cells and related metabolic pathways are introduced, and anti-tumor strategies developed to target nutrient deprivation are described. In addition to tumor cells, the nutritional and metabolic characteristics of other cells in the tumor microenvironment (including macrophages, neutrophils, natural killer cells, T cells, and cancer-associated fibroblasts) and related new anti-tumor strategies are also summarized. In conclusion, recent advances in anti-tumor strategies targeting nutrient blockade are reviewed, and the challenges and prospects of these anti-tumor strategies are discussed, which are of theoretical significance for optimizing the clinical application of tumor nutrition deprivation strategies.

NK cell-based immunotherapy for hepatocellular carcinoma: Challenges and opportunities

Hepatocellular carcinoma (HCC) remains one of the most challenging malignancies globally, characterized by significant heterogeneity, late-stage diagnosis, and resistance to treatment. In recent years, the advent of immune-checkpoint blockades (ICBs) and targeted immune cell therapies has marked a substantial advancement in HCC treatment. However, the clinical efficacy of these existing therapies is still limited, highlighting the urgent need for new breakthroughs. Natural killer (NK) cells, a subset of the innate lymphoid cell family, have shown unique advantages in the anti-tumour response. With increasing evidence suggesting the crucial role of dysfunctional NK cells in the pathogenesis and progression of HCC, considerable efforts have been directed toward exploring NK cells as a potential therapeutic target for HCC. In this review, we will provide an overview of the role of NK cells in normal liver immunity and in HCC, followed by a detailed discussion of various NK cell-based immunotherapies and their potential applications in HCC treatment.

Comprehensive single-cell pan-cancer atlas unveils IFI30+ macrophages as key modulators of intra-tumoral immune dynamics

Background

The convergence of macrophage-targeted strategies with immune checkpoint blockade therapies defines a pivotal avenue in contemporary tumor therapy. Identifying robust genetic regulators in this context is imperative.

Methods

This study elucidates IFI30's role in enhancing Major Histocompatibility Complex II (MHC-II) restriction antigen processing. Despite its recognition in cancer immunotherapy, IFI30 remains a nascent focus. Our approach involves a multi-omics analysis of IFI30 tumor immunological profile in the macrophage-mediated Tumor Microenvironment (TME), spanning various cancers and bolstered by rigorous co-culture laboratory work.

Results

IFI30 predominantly localizes in monocyte/macrophage populations, correlating strongly with immune cell infiltration. Substantiated by single-cell analysis, IFI30 exhibits significant functional enrichment in immune-related pathways. Co-expression with immune-related genes, including MHC elements and immune checkpoints, further validates its relevance.

Conclusion

Our study positions IFI30 as a promising immunotherapeutic target. Pan-cancer analyses and glioblastoma multiforme (GBM) investigations collectively underscore IFI30's potential as a TME modulator, particularly in its interaction with M2-macrophages. IFI30 emerges as a prospective intervention point in the immunotherapeutic landscape.

Elucidating the role of pyrimidine metabolism in prostate cancer and its therapeutic implications

Our study aims to investigate the role of pyrimidine metabolism in prostate cancer and its associations with the immune microenvironment, drug sensitivity, and tumor mutation burden. Through transcriptomic and single-cell RNA sequencing analyses, we explored metabolic pathway enrichment, immune infiltration patterns, and differential gene expression in prostate cancer samples. The results showed that pyrimidine metabolism-related genes were significantly upregulated in the P2 subgroup compared to the P1 subgroup, with enhanced metabolic activity observed in basal and luminal epithelial cells. In addition, immune infiltration analysis revealed a strong correlation between pyrimidine metabolism and immune cell regulation, particularly involving T cell activity. Tumors in the P2 subgroup, characterized by higher pyrimidine metabolism, exhibited greater infiltration of activated CD4 + T cells and M2 macrophages, indicating a potential link between metabolic reprogramming and the immune response in prostate cancer. Drug sensitivity analysis further demonstrated that tumors with elevated pyrimidine metabolism displayed increased responsiveness to several chemotherapeutic agents, including BI-2536, JW-7-24-1, and PAC-1, suggesting that targeting pyrimidine metabolism may enhance treatment efficacy. Moreover, key genes involved in pyrimidine de novo synthesis, such as RRM2, were identified as potential drivers of tumor progression, providing new insights into the molecular mechanisms underlying aggressive prostate cancer phenotypes. In conclusion, pyrimidine metabolism plays a critical role in prostate cancer progression, influencing immune infiltration and drug sensitivity. Targeting this metabolic pathway offers a promising strategy for the development of new therapeutic approaches, particularly for overcoming drug resistance and improving outcomes in patients with advanced prostate cancer.

Emerging role of metabolic reprogramming in the immune microenvironment and immunotherapy of thyroid cancer

The metabolic reprogramming of cancer cells is a hallmark of many malignancies. To meet the energy acquisition needs of tumor cells for rapid proliferation, tumor cells reprogram their nutrient metabolism, which is caused by the abnormal expression of transcription factors and signaling molecules related to energy metabolic pathways as well as the upregulation and downregulation of abnormal metabolic enzymes, receptors, and mediators. Thyroid cancer (TC) is the most common endocrine tumor, and immunotherapy has become the mainstream choice for clinical benefit after the failure of surgical, endocrine, and radioiodine therapies. TC change the tumor microenvironment (TME) through nutrient competition and metabolites, causing metabolic reprogramming of immune cells, profoundly changing immune cell function, and promoting immune evasion of tumor cells. A deeper understanding of how metabolic reprogramming alters the TME and controls immune cell fate and function will help improve the effectiveness of TC immunotherapy and patient outcomes. This paper aims to elucidate the metabolic communication that occurs between immune cells around TC and discusses how metabolic reprogramming in TC affects the immune microenvironment and the effectiveness of anti-cancer immunotherapy. Finally, targeting key metabolic checkpoints during metabolic reprogramming, combined with immunotherapy, is a promising strategy.

Tumor metabolic regulators: key drivers of metabolic reprogramming and the promising targets in cancer therapy

Metabolic reprogramming within the tumor microenvironment (TME) is a hallmark of cancer and a crucial determinant of tumor progression. Research indicates that various metabolic regulators form a metabolic network in the TME and interact with immune cells, coordinating the tumor immune response. Metabolic dysregulation creates an immunosuppressive TME, impairing the antitumor immune response. In this review, we discuss how metabolic regulators affect the tumor cell and the crosstalk of TME. We also summarize recent clinical trials involving metabolic regulators and the challenges of metabolism-based tumor therapies in clinical translation. In a word, our review distills key regulatory factors and their mechanisms of action from the complex reprogramming of tumor metabolism, identified as tumor metabolic regulators. These regulators provide a theoretical basis and research direction for the development of new strategies and targets in cancer therapy based on tumor metabolic reprogramming.

Pericytes and Extracellular Vesicle Interactions in Neurovascular Adaptation to Chronic Arterial Hypertension

BACKGROUND

Chronic arterial hypertension restructures the vascular architecture of the brain, leading to a series of pathological responses that culminate in cerebral small-vessel disease. Pericytes respond dynamically to vascular challenges; however, how they manifest under the continuous strain of hypertension has not been elucidated.

METHODS AND RESULTS

In this study, we characterized pericyte behavior alongside hypertensive states in the spontaneously hypertensive stroke-prone rat model, focusing on their phenotypic and metabolic transformation. Flow cytometry was used to characterize pericytes by their expression of platelet-derived growth factor receptor β, neuroglial antigen 2, cluster of differentiation 13-alanyl aminopeptidase, and antigen Kiel 67. Microvessels were isolated for gene expression profiling and in vitro pericyte expansion. Immunofluorescence validated the cell culture model. Plasma-derived extracellular vesicles from hypertensive rodents were applied as a treatment to assess their effects on pericyte function and detailed metabolic assessments on enriched pericytes measured oxidative phosphorylation and glycolysis. Our results reveal a shift in platelet-derived growth factor receptor β+ pericytes toward increased neuroglial antigen 2 and cluster of differentiation 13-alanyl aminopeptidase coexpression, indicative of their critical role in vascular stabilization and inflammatory responses within the hypertensive milieu. Significant alterations were found within key pathways including angiogenesis, blood-brain barrier integrity, hypoxia, and inflammation. Circulating extracellular vesicles from hypertensive rodents distinctly influenced pericyte mitochondrial function, evidencing their dual role as carriers of disease pathology and potential therapeutic agents. Furthermore, a shift toward glycolytic metabolism in hypertensive pericytes was confirmed, coupled with ATP production dysregulation.

CONCLUSIONS

Our findings demonstrate that cerebral pericytes undergo phenotypic and metabolic reprogramming in response to hypertension, with hypertensive-derived plasma-derived extracellular vesicles impairing their mitochondrial function. Importantly, plasma-derived extracellular vesicles from normotensive controls restore this function, suggesting their potential as both therapeutic agents and precision biomarkers for hypertensive vascular complications. Further investigation into plasma-derived extracellular vesicle cargo is essential to further explore their therapeutic potential in vascular health.

Metabolic Signaling in the Tumor Microenvironment

Cancer cells must reprogram their metabolism to sustain rapid growth. This is accomplished in part by switching to aerobic glycolysis, uncoupling glucose from mitochondrial metabolism, and performing anaplerosis via alternative carbon sources to replenish intermediates of the tricarboxylic acid (TCA) cycle and sustain oxidative phosphorylation (OXPHOS). While this metabolic program produces adequate biosynthetic intermediates, reducing agents, ATP, and epigenetic remodeling cofactors necessary to sustain growth, it also produces large amounts of byproducts that can generate a hostile tumor microenvironment (TME) characterized by low pH, redox stress, and poor oxygenation. In recent years, the focus of cancer metabolic research has shifted from the regulation and utilization of cancer cell-intrinsic pathways to studying how the metabolic landscape of the tumor affects the anti-tumor immune response. Recent discoveries point to the role that secreted metabolites within the TME play in crosstalk between tumor cell types to promote tumorigenesis and hinder the anti-tumor immune response. In this review, we will explore how crosstalk between metabolites of cancer cells, immune cells, and stromal cells drives tumorigenesis and what effects the competition for resources and metabolic crosstalk has on immune cell function.

Single-Cell Multiomics Identifies Glycan Epitope LacNAc as a Potential Cell-Surface Effector Marker of Peripheral T Cells in Bladder Cancer Patients

Cancer is a systemic disease continuously monitored and responded to by the human global immune system. Peripheral blood immune cells, integral to this surveillance, exhibit variable phenotypes during tumor progression. Glycosylation, as one of the most prevalent and significant post-translational modifications of proteins, plays a crucial role in immune system recognition and response. Glycan analysis has become a key method for biomarker discovery. LacNAc, a prominent glycosylation modification, regulates immune cell activity and function. Therefore, we applied our previously developed single-cell glycomic multiomics to analyze peripheral blood in cancer patients. This platform utilizes chemoenzymatic labeling with DNA barcodes for detecting and quantifying LacNAc levels at single-cell resolution without altering the transcriptional status of immune cells. For the first time, we systematically integrated single-cell transcriptome, T cell receptor (TCR) repertoire, and glycan epitope LacNAc analyses in tumor-patient-derived peripheral blood. Our integrated analysis reveals that lower-stage bladder cancer patients showed significantly higher levels of LacNAc in peripheral T cells, and peripheral T cells with high levels of cell-surface LacNAc exhibit higher cytotoxicity and TCR clonal expansion. In summary, we identified LacNAc as a potential cell-surface effector marker for peripheral T cells in bladder cancer patients, which enhances our understanding of peripheral immune cells and offers potential advancements in liquid biopsy.

Prediction of prognosis, efficacy of lung adenocarcinoma by machine learning model based on immune and metabolic related genes

BACKGROUND

The aim of this study is to integrate immune and metabolism-related genes in order to construct a predictive model for predicting the prognosis and treatment response of LUAD(lung adenocarcinoma) patients, aiming to address the challenges posed by this highly lethal and heterogeneous disease.

MATERIAL AND METHODS

Using TCGA-LUAD as the training subset, differential gene expression analysis, batch survival analysis, Lasso regression analysis, univariate and multivariate Cox regression analysis were performed to construct prognostic related gene models. GEO queue as validation subsets, is used to validate build Riskscore. Then, we explore the Riskscore and mutation status, immune cell infiltration, the relationship between immune therapy and chemotherapy, and build the model of the nomogram.

RESULTS

The Riskscore has been determined to be composed of seven gene. In the high-risk group defined by this score, both early-stage and advanced-stage LUAD patients exhibit a decreased overall survival rate. The mutation status of patients as well as immune cell infiltration show associations with the Riskscore value obtained from these genes' expression levels. Furthermore, there exist variations in response to immunotherapy as well as sensitivity to commonly used chemotherapy drugs among different individuals. Lastly, when using a column line plot model based on the calculated Riskscore values, we obtain a concordance index (C-index) was 0 .716 (95% CI 0.671-0.762), and time-dependent ROC predicted probabilities of 1-, 3- and 5-year survival for LUAD patients were 0.752, 0.725 and 0.654, respectively.

CONCLUSION

In conclusion, we have successfully developed a predictive model incorporating immune and metabolism-related genes, encompassing gene expression levels of CAT/CCL20/GPI/INSL4 NT5E/GSTA3/GNPNAT1. This comprehensive model not only enables the prognosis prediction for LUAD patients but also facilitates the prediction of their response to first-line chemotherapy drugs and immune checkpoint inhibitors, thus demonstrating its broad potential in clinical applications. However, our study still has limitations as it is based on TCGA and GEO databases with limited pathological characteristics of patients. Therefore, more practical and valuable factors are needed to predict efficacy. The crosstalk between metabolism and immunity remains to be explored. Finally, this study lacks experimental evidence for the underlying gene expression of prognosis and further research is required.

In silico, in vitro, and ex vivo analysis reveals miR-27a-3p and miR-155-5p as key microRNAs for glioblastoma progression: Insights into Th1 differentiation and apoptosis induction

We explored key microRNAs (miRNAs) related to tumorigenesis and immune modulation in glioblastoma (GBM), employing in silico, in vitro, and ex vivo analysis along with an assessment of the cellular impacts resulting from miRNA inhibition. GBM and T cells miRNA expression profiles from public datasets were used to evaluate differentially expressed miRNAs (DEmiRNAs). Some DEmiRNAs were chosen for validation in GBM cell lines, primary cell cultures, and brain tumor patient samples, using RT-qPCR. Target genes and pathways were identified with bioinformatic analyses. In silico functional enrichment analysis revealed that miR-27a-3p and miR-155-5p modulate immune, metabolic, and GBM-related pathways. A172 cells were transfected with miRNA inhibitors and the effects on cellular processes and immunomodulation were analyzed by co-culture assays and flow cytometry. Upon validation, miR-27a-3p and miR-155-5p miRNAs expressions were consistently increased. Inhibiting these two miRNAs reduced cell viability, but only the inhibition of miR-27a-3p led to apoptosis. Co-culture assays showed an increase in Th1 cells along with elevated Th1/Treg and Th17/Treg ratios, and an increase in Th17 cells exclusively with miR-155-5p inhibition. Immune cells' gene expression modulation induced an antitumor profile, concomitant with an increase in the expression of apoptotic genes in cancer cells after co-culture. This study unveils potential targets for immune and tumor regulation, highlighting overexpressed miRNAs modulation as a novel therapeutic approach for GBM.

Therapeutic potential of trained immunity for malignant disease

Trained immunity (TI) is functional memory displayed by innate immune cells (IICs). TI facilitates rapid, non-specific responses to pathogens upon secondary challenge. It is driven by immunological signaling and metabolic rewriting via epigenetic alteration, triggered by recognition of certain stimuli. Recently, immune checkpoint inhibitors have come into common use in clinical oncology settings, and genetically engineered cytotoxic T cells comprise a potent cancer treatment strategy. However, the contributions of TI in the tumor microenvironment (TME) are only beginning to be uncovered. Accumulating evidence that various microorganisms and vaccines convey tumoricidal ability suggest that TI may become a useful anti-cancer tool. The expected roles of TI in tumor therapy are the 1) promotion of proinflammatory cytokine section, 2) enhancement of phagocytosis, 3) quick expansion and recruitment of cancer-specific cytotoxic T cells to the TME through neoantigen presentation, 4) reversal of immunosuppression in the TME, and 5) removal of pathogens associated with carcinogenesis or tumor development. Medium- to long-term TI durability may reduce the risk of tumor development. Recent findings on TI usher in new aspirations for cancer treatment.

Role of microglia polarization induced by glucose metabolism disorder in the cognitive impairment of mice from PM2.5 exposure

Studies have found that PM2.5 can damage the brain, accelerate cognitive impairment, and increase the risk of developing a variety of neurodegenerative diseases. However, the potential molecular mechanisms by which PM2.5 causes learning and memory problems are yet to be explored. In this study, we evaluated the neurotoxic effects in mice after 12 weeks of PM2.5 exposure, and found that this exposure resulted in learning and memory disorders, pathological brain damage, and M1 phenotype polarization on microglia, especially in the hippocampus. The severity of this damage increased with increasing PM2.5 concentration. Proteomic analysis, as well as validation results, suggested that PM2.5 exposure led to abnormal glucose metabolism in the mouse brain, which is mainly characterized by significant expression of hexokinase, phosphofructokinase, and lactate dehydrogenase. We therefore administered the glycolysis inhibitor 2-deoxy-d-glucose (2-DG) to the mice exposed to PM2.5, and showed that inhibition of glycolysis by 2-DG significantly alleviated PM2.5-induced hippocampal microglia M1 phenotype polarization, and reduced the release of inflammatory factors, improved synaptic structure and related protein expression, which alleviated the cognitive impairment induced by PM2.5 exposure. In summary, our study found that abnormal glucose metabolism-mediated inflammatory polarization of microglia played a role in learning and memory disorders in mice exposed to PM2.5. This study provides new insights into the neurotoxicity caused by PM2.5 exposure, and provides some theoretical references for the prevention and control of cognitive impairment induced by PM2.5 exposure.

Nano-medicine therapy reprogramming metabolic network of tumour microenvironment: new opportunity for cancer therapies

Metabolic heterogeneity is one of the characteristics of tumour cells. In order to adapt to the tumour microenvironment of hypoxia, acidity and nutritional deficiency, tumour cells have undergone extensive metabolic reprogramming. Metabolites involved in tumour cell metabolism are also very different from normal cells, such as a large number of lactate and adenosine. Metabolites play an important role in regulating the whole tumour microenvironment. Taking metabolites as the target, it aims to change the metabolic pattern of tumour cells again, destroy the energy balance it maintains, activate the immune system, and finally kill tumour cells. In this paper, the regulatory effects of metabolites such as lactate, glutamine, arginine, tryptophan, fatty acids and adenosine were reviewed, and the related targeting strategies of nano-medicines were summarised, and the future therapeutic strategies of nano-drugs were discussed. The abnormality of tumour metabolites caused by tumour metabolic remodelling not only changes the energy and material supply of tumour, but also participates in the regulation of tumour-related signal pathways, which plays an important role in the survival, proliferation, invasion and metastasis of tumour cells. Regulating the availability of local metabolites is a new aspect that affects tumour progress. (The graphical abstract is by Figdraw).

Profiling Breast Tumor Heterogeneity and Identifying Breast Cancer Subtypes Through Tumor-Associated Immune Cell Signatures and Immuno Nano Sensors

Breast cancer is a complex and heterogeneous disease with varying cellular, genetic, epigenetic, and molecular expressions. The detection of intratumor heterogeneity in breast cancer poses significant challenges due to its complex multifaceted characteristics, yet its identification is crucial for guiding effective treatment decisions and understanding the disease progression. Currently, there exists no method capable of capturing the full extent of breast tumor heterogeneity. In this study, the aim is to identify and characterize metabolic heterogeneity in breast tumors using immune cells and an ultrafast laser-fabricated Immuno Nano Sensor. Combining spectral markers from both Natural Killer (NK) and T cells, a machine-learning approach is implemented to distinguish cancer from healthy samples, identify primary versus metastatic tumors, and determine estrogen receptor (ER)/progesterone receptor (PR) status at the single-cell level. The platform successfully distinguished heterogeneous breast cancer samples from healthy individuals, achieving 97.8% sensitivity and 92.2% specificity, and accurately identified primary tumors from metastatic tumors. Characteristic spectral signatures allow for discrimination between ER/PR-positive and negative tumors with 97.5% sensitivity. This study demonstrates the potential of immune cell-based metabolic profiling in providing a comprehensive assessment of breast tumor heterogeneity and paving the way for minimally invasive liquid biopsy approaches in breast cancer diagnosis and management.

LncRNA mediated metabolic reprogramming: the chief culprits of solid tumor malignant progression: an update review

Metabolism reprogramming (MR) is one of the top ten hallmarks of malignant tumors. The aberrant activation of MR has been recognized as a critical contributory factor to the malignant progression of solid tumors. Moreover, various long non-coding RNAs (lncRNAs) are implicated in the aberrant activation of MR in solid tumor cells. Therefore, in this review, we mainly focus on summarizing the functional relevance and molecular mechanistic underpinnings of lncRNAs in modulating MR of solid tumors by targeting glucose metabolism, lipid metabolism, affecting mitochondrial function, and regulating interactions between tumor and non-tumor cells in tumor microenvironment. Besides, we also underscore the potential for constructing lncRNAs-centered tumor metabolic regulation networks and developing novel anti-tumor strategies by targeting lncRNAs and abnormal MR. Ultimately, this review seeks to offer new targets and avenues for the clinical treatment of solid tumors in the future.

Macrophage polarization and metabolic reprogramming in abdominal aortic aneurysm

BACKGROUND

Abdominal aortic aneurysm (AAA) is a macrovascular disease with high morbidity and mortality in the elderly. The limitation of the current management is that most patients can only be followed up until the AAA diameter increases to a threshold, and surgical intervention is recommended. The development of preventive and curative drugs for AAA is urgently needed. Macrophage-mediated immune inflammation is one of the key pathological links in the occurrence and development of AAA.

AIMS

This review article aims to evaluate the impact of immunometabolism on macrophage biology and its role in AAA.

METHODS

We analyze publications focusing on the polarization and metabolic reprogramming in macrophages as well as their potential impact on AAA, and summarize the potential interventions that are currently available to regulate these processes.

RESULTS

The phenotypic and functional changes in macrophages are accompanied by significant alterations in metabolic pathways. The interaction between macrophage polarization and metabolic pathways significantly influences the progression of AAA.

CONCLUSION

Macrophage polarization is a manifestation of the gross dichotomy of macrophage function into pro-inflammatory killing and tissue repair, that is, classically activated M1 macrophages and alternatively activated M2 macrophages. Macrophage functions are closely linked to metabolic changes, and the emerging field of immunometabolism is providing unique insights into the role of macrophages in AAA. It is essential to further investigate the precise metabolic changes and their functional consequences in AAA-associated macrophages.

Single cell atlas reveals multilayered metabolic heterogeneity across tumour types

BACKGROUND

Metabolic reprogramming plays a pivotal role in cancer progression, contributing to substantial intratumour heterogeneity and influencing tumour behaviour. However, a systematic characterization of metabolic heterogeneity across multiple cancer types at the single-cell level remains limited.

METHODS

We integrated 296 tumour and normal samples spanning six common cancer types to construct a single-cell compendium of metabolic gene expression profiles and identify cell type-specific metabolic properties and reprogramming patterns. A computational approach based on non-negative matrix factorization (NMF) was utilised to identify metabolic meta-programs (MMPs) showing intratumour heterogeneity. In-vitro cell experiments were conducted to confirm the associations between MMPs and chemotherapy resistance, as well as the function of key metabolic regulators. Survival analyses were performed to assess clinical relevance of cellular metabolic properties.

FINDINGS

Our analysis revealed shared glycolysis upregulation and divergent regulation of citric acid cycle across different cell types. In malignant cells, we identified a colorectal cancer-specific MMP associated with resistance to the cuproptosis inducer elesclomol, validated through in-vitro cell experiments. Furthermore, our findings enabled the stratification of patients into distinct prognostic subtypes based on metabolic properties of specific cell types, such as myeloid cells.

INTERPRETATION

This study presents a nuanced understanding of multilayered metabolic heterogeneity, offering valuable insights into potential personalized therapies targeting tumour metabolism.

FUNDING

National Key Research and Development Program of China (2021YFA1300601). National Natural Science Foundation of China (key grants 82030081 and 81874235). The Shenzhen High-level Hospital Construction Fund and Shenzhen Basic Research Key Project (JCYJ20220818102811024). The Lam Chung Nin Foundation for Systems Biomedicine.

In silico and pharmacological evaluation of GPR65 as a cancer immunotherapy target regulating T-cell functions

The success of cancer immunotherapies such as immune checkpoint inhibitors, CAR T-cells and immune cell engagers have provided clinicians with tools to bypass some of the limitations of cancer immunity. However, numerous tumour factors curtail the immune response against cancer and limit the efficiency of immuno-oncology (IO) therapies. Acidification of the extra-cellular tumour environment consecutive to aberrant cancer cell metabolism is a well-known promoter of oncogenic processes that also acts as an immune regulator. Yet, the suppressive mechanisms of low extra-cellular pH on anti-cancer immunity remain poorly understood. Recent reports have suggested that GPR65, a Gαs-coupled proton-sensing GPCR broadly expressed in the immune system, may act as an immune suppressant detrimental to anti-tumour immunity. So far, the immuno-regulatory properties of GPR65 in acidic milieux have mostly been documented in macrophages and myeloid cells. Our computational evaluation of GPR65's transcriptomic expression profile and potential as an IO target using public datasets prompted us to further investigate its functions in human T-cells. To this end, we identified and validated GPR65 small molecule inhibitors active in in vitro cellular assays and we showed that GPR65 inhibition promoted the killing capacity of antigen-specific human T-cells. Our results broaden the scope of GPR65 as an IO target by suggesting that its inhibition may enhance T-cell anti-tumour activity and provide useful pharmacological tools to further investigate the therapeutic potential of GPR65 inhibition.

Engineered microparticles modulate arginine metabolism to repolarize tumor-associated macrophages for refractory colorectal cancer treatment

BACKGROUND

Arginase is abundantly expressed in colorectal cancer and disrupts arginine metabolism, promoting the formation of an immunosuppressive tumor microenvironment. This significant factor contributes to the insensitivity of colorectal cancer to immunotherapy. Tumor-associated macrophages (TAMs) are major immune cells in this environment, and aberrant arginine metabolism in tumor tissues induces TAM polarization toward M2-like macrophages. The natural compound piceatannol 3'-O-glucoside inhibits arginase activity and activates nitric oxide synthase, thereby reducing M2-like macrophages while promoting M1-like macrophage polarization.

METHODS

The natural compounds piceatannol 3'-O-glucoside and indocyanine green were encapsulated within microparticles derived from tumor cells, termed PG/ICG@MPs. The enhanced cancer therapeutic effect of PG/ICG@MP was assessed both in vitro and in vivo.

RESULTS

PG/ICG@MP precisely targets the tumor site, with piceatannol 3'-O-glucoside concurrently inhibiting arginase activity and activating nitric oxide synthase. This process promotes increased endogenous nitric oxide production through arginine metabolism. The combined actions of nitric oxide and piceatannol 3'-O-glucoside facilitate the repolarization of tumor-associated macrophages toward the M1 phenotype. Furthermore, the increase in endogenous nitric oxide levels, in conjunction with the photodynamic effect induced by indocyanine green, increases the quantity of reactive oxygen species. This dual effect not only enhances tumor immunity but also exerts remarkable inhibitory effects on tumors.

CONCLUSION

Our research results demonstrate the excellent tumor-targeting effect of PG/ICG@MPs. By modulating arginine metabolism to improve the tumor immune microenvironment, we provide an effective approach with clinical translational significance for combined cancer therapy.

MerTK+ macrophages promote melanoma progression and immunotherapy resistance through AhR-ALKAL1 activation

Despite our increasing understanding of macrophage heterogeneity, drivers of macrophage phenotypic and functional polarization in the microenvironment are not fully elucidated. Here, our single-cell RNA sequencing data identify a subpopulation of macrophages expressing high levels of the phagocytic receptor MER proto-oncogene tyrosine kinase (MerTK+ macrophages), which is closely associated with melanoma progression and immunotherapy resistance. Adoptive transfer of the MerTK+ macrophages into recipient mice notably accelerated tumor growth regardless of macrophage depletion. Mechanistic studies further revealed that ALK And LTK Ligand 1 (ALKAL1), a target gene of aryl hydrocarbon receptor (AhR), facilitated MerTK phosphorylation, resulting in heightened phagocytic activity of MerTK+ macrophages and their subsequent polarization toward an immunosuppressive phenotype. Specifically targeted delivery of AhR antagonist to tumor-associated macrophages with mannosylated micelles could suppress MerTK expression and improved the therapeutic efficacy of anti-programmed cell death ligand 1 therapy. Our findings shed light on the regulatory mechanism of MerTK+ macrophages and provide strategies for improving the efficacy of melanoma immunotherapy.

The Values of PDK1 and LDH Levels in Patients with Sepsis and Septic Shock: A Prospective Observational Study

Background

Metabolic changing is the significant host stress response during sepsis, but there is increasing evidence that uncontrolled metabolic reprogramming is a contributing factor to sepsis. Nevertheless, its association with outcome in patients with sepsis has been poorly investigated. As the key enzyme of metabolic reprogramming, the clinical value of PDK1 and LDH in patients with sepsis will be investigated in this study.

Methods

We collected serum from 167 ICU patients within 24 hours of admission for a single-center prospective observational study. The levels of PDK1 and LDH were detected by enzyme-linked adsorption method. Pearson or Spearman coefficient for correlation analysis between PDK1, LDH and clinical indicators. Areas under the ROC curves for evaluation of mortality prediction. Kaplan-Meier survival curve analysis was performed, and Cox proportional hazards model was performed to determine the risk factors for 28-day mortality.

Results

The PDK1/LDH in the septic shock group was statistically different between both the sepsis group and ICU control group, and had good correlation with ScvO2 and lactate. In predicting 28-day mortality in patients with sepsis, the best AUC was observed for PDK1/LDH, and was higher than the AUC for PDK1, lactate, and SOFA. Additionally, patients with lower PDK1/LDH had markerablely higher 28-day mortality. The multivariate Cox proportional hazards model revealed that PDK1/LDH < 0.1808 were the independent risk factors for 28-day mortality in sepsis.

Conclusion

The level of PDK1/LDH at admission was markedly decreased in patients with septic shock, which can serve as a novel independent prognostic biomarker for predicting mortality.

Pre-metastatic niche: formation, characteristics and therapeutic implication

Distant metastasis is a primary cause of mortality and contributes to poor surgical outcomes in cancer patients. Before the development of organ-specific metastasis, the formation of a pre-metastatic niche is pivotal in promoting the spread of cancer cells. This review delves into the intricate landscape of the pre-metastatic niche, focusing on the roles of tumor-derived secreted factors, extracellular vesicles, and circulating tumor cells in shaping the metastatic niche. The discussion encompasses cellular elements such as macrophages, neutrophils, bone marrow-derived suppressive cells, and T/B cells, in addition to molecular factors like secreted substances from tumors and extracellular vesicles, within the framework of pre-metastatic niche formation. Insights into the temporal mechanisms of pre-metastatic niche formation such as epithelial-mesenchymal transition, immunosuppression, extracellular matrix remodeling, metabolic reprogramming, vascular permeability and angiogenesis are provided. Furthermore, the landscape of pre-metastatic niche in different metastatic organs like lymph nodes, lungs, liver, brain, and bones is elucidated. Therapeutic approaches targeting the cellular and molecular components of pre-metastatic niche, as well as interventions targeting signaling pathways such as the TGF-β, VEGF, and MET pathways, are highlighted. This review aims to enhance our understanding of pre-metastatic niche dynamics and provide insights for developing effective therapeutic strategies to combat tumor metastasis.

The potential role of purinergic signaling in cancer therapy: perspectives on anti-CD73 strategies for prostate cancer

Purines and pyrimidines are signaling molecules in the tumor microenvironment that affect cancer immunity. The purinergic signaling pathways have been shown to play an important role in the development and progression of cancer. CD39 and CD73 are ectonucleotidases responsible for breaking down ATP or ADP into adenosine, which regulates immunosuppression in various types of cancer. These enzymes have been studied as a potential therapeutic target in immunotherapy, and recent research suggests a correlation between ectonucleotidases and clinical outcomes in cancer.Prostate cancer is the most diagnosed cancer in men, after non-melanoma skin tumors, and is the second leading cause of death in men in the world. Despite having long survival periods, patients often receive excessive or insufficient treatment. Within this complex landscape, the adenosine/CD73 pathway plays a crucial role. Therefore, this review aims to highlight new findings on the potential role of purinergic signaling in cancer treatment and emphasizes the importance of anti-CD73 as a pharmacological strategy for prostate cancer therapy.

The BRD4 Inhibitor I-BET-762 Reduces HO-1 Expression in Macrophages and the Pancreas of Mice

In pancreatic cancer, the tumor microenvironment (TME) accounts for up to 90% of the tumor mass. Pancreatitis, characterized by the increased infiltration of macrophages into the pancreas, is a known risk factor for pancreatic cancer. The NRF2 (nuclear factor erythroid 2-related factor 2) transcription factor regulates responses to oxidative stress and can promote cancer and chemoresistance. NRF2 also attenuates inflammation through the regulation of macrophage-specific genes. Heme oxygenase 1 (HO-1) is expressed by anti-inflammatory macrophages to degrade heme, and its expression is dependent on NRF2 translocation to the nucleus. In macrophages stimulated with conditioned media from pancreatic cancer cells, HO-1 protein levels increased, which correlated with higher NRF2 expression in the nuclear fraction. Significant differences in macrophage infiltration and HO-1 expression were detected in LSL-KrasG12D/+; Pdx-1-Cre (KC) mice, Nrf2 whole-body knockout (KO) mice and wildtype mice with pancreatitis. Since epigenetic modulation is a mechanism used by tumors to regulate the TME, using small molecules as epigenetic modulators to activate immune recognition is therapeutically desirable. When the bromodomain inhibitor I-BET-762 was used to treat macrophages or mice with pancreatitis, high levels of HO-1 were reduced. This study shows that bromodomain inhibitors can be used to prevent physiological responses to inflammation that promote tumorigenesis.