Lactate, traditionally considered just a byproduct of metabolism, is now understood to be a vital regulator in energy metabolism, immune function, and epigenetic changes. Besides serving as an alternative energy source t...Lactate, traditionally considered just a byproduct of metabolism, is now understood to be a vital regulator in energy metabolism, immune function, and epigenetic changes. Besides serving as an alternative energy source through the "lactate shuttle," it acts as a signaling molecule influencing both normal and abnormal processes in various organs. New research has emphasized its role in lactylation of histones and non-histones, a novel post-translational modification linking metabolic activity with gene expression and immune response. Lactate contributes to immunosuppression, angiogenesis, and the spread of tumors within the tumor microenvironment. Its accumulation is also linked to cardiovascular, metabolic, and neurodegenerative conditions. This shift in metabolism underscores lactate's growing importance in both health and disease, presenting novel therapeutic opportunities, especially in the treatment of cancer and metabolic disorders. This review synthesizes emerging insights into lactate's multifaceted roles and discusses promising therapeutic strategies targeting lactate metabolism, transport, and downstream signaling pathways, with an emphasis on candidates advancing toward clinical translation.
BACKGROUND: Hepatocellular carcinoma (HCC) is the most common primary liver carcinoma with high lethality. Both of hepatitis B virus (HBV) and Clonorchis sinensis (C. sinensis) are critical infectious contributors to HCC...BACKGROUND: Hepatocellular carcinoma (HCC) is the most common primary liver carcinoma with high lethality. Both of hepatitis B virus (HBV) and Clonorchis sinensis (C. sinensis) are critical infectious contributors to HCC development. However, the inter-tumor heterogeneity and tumor microenvironment (TME) of HCC patients with different infectious background remain largely unknown. METHODS: We compiled a cohort of 269 primary HCC patients to assess the clinical impact of C. sinensis and HBV infections on patient prognosis. Single-cell RNA sequencing (scRNA-seq) and spatial transcriptomic (ST-seq) analyses were performed on tumor and adjacent normal samples from C. sinensis-associated HCC (CP), and double-infection HCC (DP) patients. Additionally, we integrated publicly available scRNA-seq and ST-seq datasets from HBV-associated (HP) patients. Immunofluorescence, immunohistochemistry and in vitro experiments were conducted to validate inter-tumor heterogeneity among the three HCC subtypes. RESULTS: C. sinensis infection is significantly associated with poorer prognosis in HCC patients. Multi-omics analyses revealed distinct inter-tumor heterogeneity in epithelial, immune, and stromal compartments across different HCC subtypes. Tumor cells in the DP group exhibited more malignant marker expression, higher copy number variation scores, increased activation of p53 pathway, and worse survival outcomes. Compared with other HCC subtypes, the TME in DP samples was enriched with SPP1 macrophages, exhausted CD8 T cells and COL1A1 fibroblasts. In contrast, the CP and HP groups showed higher proportions of M2-like macrophages and ENPP2 liver vascular endothelial cells, respectively. CONCLUSION: These findings decipher the cellular signatures and their interactions within the TME, shedding light on the inter-tumoral heterogeneity driven by different infections, and the development of targeted therapies for infectious HCC.
BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies, but the molecular mechanisms underlying CRC progression are not well-understood. Accumulating evidence suggests that circular RNAs (circRNAs) pl...BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies, but the molecular mechanisms underlying CRC progression are not well-understood. Accumulating evidence suggests that circular RNAs (circRNAs) play important roles in genesis and development of cancer. However, the roles and molecular mechanisms of circRNAs in CRC remain largely unelucidated. METHODS: The differential expression patterns of circRNAs between primary CRC tumor tissues and corresponding liver metastases were profiled by RNA sequencing. Associations between circPTGR1 expression and clinicopathological features as well as prognosis were analyzed among CRC patients. The effect of circPTGR1 on CRC growth and metastasis was explored through in vitro, in vivo—comprising subcutaneous xenograft, tail-vein lung metastasis, and intrasplenic liver metastasis models—and notably, patient-derived organoid (PDO) assays. The reciprocal regulation among circPTGR1, miR-4725-5p, and EIF4A3, together with the interaction between miR-4725-5p and FAK (Focal Adhesion Kinase), was predicted by bioinformatic analyses and subsequently validated using qRT-PCR, western blotting, RNA immunoprecipitation (RIP), and dual-luciferase reporter assays. Further confirmation of these regulatory interactions was performed in clinical CRC tissues, PDOs, and xenograft models by qRT-PCR, western blotting, and immunohistochemistry (IHC). RESULTS: Expression of circPTGR1 was significantly upregulated in CRC and elevated circPTGR1 was associated with poor prognosis in CRC patients. In vitro and in vivo experiments demonstrated that circPTGR1 promoted the growth, migration, invasion, and metastasis of CRC. The role of circPTGR1 in enhancing CRC cell proliferation and invasiveness was confirmed utilizing PDO models. Mechanistically, circPTGR1 acted as a molecular sponge for miR-4725-5p, leading to upregulation of its target FAK and consequently activating the FAK/AKT signaling pathway. Importantly, EIF4A3 was identified as a promoter which facilitated the biogenesis of circPTGR1 and a direct downstream target of miR-4725-5p. These findings were validated through clinical CRC tissues, PDO models, and xenograft assays, supporting a novel positive feedback loop involving EIF4A3, circPTGR1, and miR-4725-5p in CRC progression via activating the FAK/AKT signaling pathway. CONCLUSIONS: EIF4A3/circPTGR1/miR-4725-5p positive feedback loop accelerates CRC proliferation and metastasis by activating the FAK/AKT signaling pathway. Therefore, circPTGR1 could serve as a potential prognostic indicator and therapeutic target for CRC.
Tumor-associated macrophages (TAMs) are among the most abundant immune components within the breast cancer (BRCA) microenvironment and exert multifaceted roles in tumor progression, immune evasion, and therapy resistance...Tumor-associated macrophages (TAMs) are among the most abundant immune components within the breast cancer (BRCA) microenvironment and exert multifaceted roles in tumor progression, immune evasion, and therapy resistance. While traditionally classified along the M1/M2 polarization axis, emerging evidence from single-cell and spatial transcriptomic studies has revealed a spectrum of phenotypically diverse, functionally distinct TAM subsets. These subsets are shaped by BRCA molecular subtype, tumor stage, and microenvironmental factors such as cytokines, hypoxia, and metabolic cues, challenging the conventional dichotomy. This review summarizes current understanding of TAM origin, polarization, and subtypes-specific functions across different breast cancers subtypes. Functionally, heterogeneous spatial-metabolic TAMs contribute to angiogenesis, metastasis, and immunosuppression—particularly their crosstalk with T cells and immune checkpoints. Emerging therapeutic strategies are discussed, including TAMs depletion and reprogramming. Altogether, to examine major challenges in TAM research, such as the lack of standardized classification systems and actionable biomarkers, proposes future directions for integrating TAM-targeted therapies into personalized immuno-oncology.
Hao Q, Zhou T, Yan H
… +22 more, Ren Z, Mao W, Huang LB, Chen YY, Wang Y, Xiao M, He Y, Xia X, Wu J, Zhang WH, Chen HN, Qian M, Zhang F, Yang L, Dai L, Zhang H, Huang C, Shu Y, Xu Y, Luo Y, Peng Y, Xu H
BACKGROUND: Double-Negative T (DNT) cells, lacking both CD4 and CD8 expression, play critical roles in cancer immunology, and have garnered increasing attention in cancer research. However, their heterogeneity and functi...BACKGROUND: Double-Negative T (DNT) cells, lacking both CD4 and CD8 expression, play critical roles in cancer immunology, and have garnered increasing attention in cancer research. However, their heterogeneity and functional diversity within the tumor microenvironment (TME) remain underexplored. METHODS: In-house and publicly available single-cell RNA sequencing (scRNA-seq) data for different cancer types were integrated after quality control and batch effect correction, followed by DNT cells separation from CD3 T cells subtypes. Functional characteristics, intercellular communication, differentiation trajectories, regulatory networks, and clinical relevance were analyzed among different DNT subsets. Key findings were validated using multiplex immunofluorescence and spatial transcriptomics to investigate the spatial localization of DNT subsets and their interactions within the TME. Impact of γδ T cells on immunotherapy response was also assessed using MC38-based murine tumor model. RESULTS: By integrating scRNA-seq data from 2,369 samples across 23 cancer types, we established a comprehensive single-cell atlas of 157,025 high-quality DNT cells. Fourteen distinct DNT subsets (6 αβ DNT and 8 γδ T cell subsets) were identified, demonstrating tumor both type-specific and shared distribution patterns, as well as unique cell-cell interaction network within the TME. These subsets displayed specialized functional profiles, including cytotoxicity, antigen presentation, and immune modulation, indicating that the functional diversity of DNT cells is largely subset-specific rather than a manifestation of multifunctionality within a single population. We also delineated divergent trajectories for αβ DNT and γδ T cell subsets, including the functional plasticity of gut-resident γδ T cells transitioning between cytotoxic and immunosuppressive states. Notably, several DNT subsets were significantly associated with favorable clinical treatment outcomes, including improved responses to cancer immunotherapy. Consistently, depletion of γδ T cells in the murine tumor model significantly decreased the efficacy of PD-1 blockade, underscoring their critical role in therapeutic response. CONCLUSIONS: Our study uncovers the previously underappreciated heterogeneity and functional diversity of DNT cells in the TME and demonstrates their profound impact on tumor progression and immunotherapy outcomes.
Pancreatic cancer remains one of the deadliest malignancies, primarily due to its highly immunosuppressive tumor microenvironment (TME) and poor response to conventional therapies. Increasing evidence highlights the gut...Pancreatic cancer remains one of the deadliest malignancies, primarily due to its highly immunosuppressive tumor microenvironment (TME) and poor response to conventional therapies. Increasing evidence highlights the gut microbiota as a pivotal regulator of antitumor immunity, modulating T cell activation, macrophage polarization, and dendritic cell function. Microbial communities and their metabolites can either inhibit or enhance immune surveillance, thereby influencing the efficacy of immunotherapies such as immune checkpoint inhibitors (ICIs) and CAR-T cell therapy. Approaches including dietary modulation, probiotics, fecal microbiota transplantation (FMT), and microbial metabolite supplementation show promise in restoring immune homeostasis and improving treatment outcomes. Additionally, gut microbiome profiling has emerged as a potential source of biomarkers for predicting therapeutic response and immune-related adverse events. This review summarizes current insights into microbiota-immune interactions in pancreatic cancer, emphasizes microbiome-targeted therapeutic strategies, and explores future opportunities for precision immunotherapy guided by microbial modulation.
BACKGROUNDS: Significant heterogeneity was observed in the epithelial-derived endometrial cancer (EC), which contributes to different prognostic outcomes. While the mechanisms involved in this heterogeneity in the tumor...BACKGROUNDS: Significant heterogeneity was observed in the epithelial-derived endometrial cancer (EC), which contributes to different prognostic outcomes. While the mechanisms involved in this heterogeneity in the tumor microenvironment (TME) of early-stage EC remain poorly defined. METHODS: Single-cell RNA sequencing, spatial transcriptomics, and multiplex immunofluorescence (mIF) were applied to characterize cellular subpopulations in early-stage EC. EC cell proliferation was assessed by CCK-8 and flow cytometry (FC). Furthermore, the epithelial dynamics and macrophage interactions were also investigated in vitro by molecular docking and GST pull-down mass spectrometry. Phagocytic activity was also evaluated by FC and immunofluorescence. Moreover, the upstream transcription factors were identified using CUT&Tag. For in vivo study, an organoid–macrophage co-culture model was established to mimic the EC microenvironment, and altered organoid proliferation and macrophage phagocytosis were confirmed. CD47 was evaluated as a potential prognostic marker by proteomic analysis and immunohistochemistry. RESULTS: We identified a previously unrecognized epithelial subpopulation (CD47⁺CDK1⁺) that was strongly linked to cell-cycle signaling and malignant proliferation. This subpopulation interacts closely with macrophages through the CD47–Galectin 9 (LGALS9) receptor-ligand pair. Functionally, CD47 inhibition suppressed EC cell proliferation and induced apoptosis, while CD47 overexpression enhanced the proliferative capacity of EC patient-derived organoids (PDOs). EC cells and PDOs engaged macrophages through the CD47–HCK (Hemopoietic Cell Kinase) axis, driving the secretion of immunosuppressive molecules LGALS9, IL-10, and TGF-β1 and forming an immunosuppressive TME. In turn, macrophage-derived LGALS9 reinforced EC cell and PDO proliferation via CD47, establishing a positive feedback loop involving CD47–HCK–LGALS9. Furthermore, estrogen-related receptor gamma (ERRγ) was identified as an upstream transcriptional regulator of CD47, and its expression was suppressed by progesterone. CONCLUSIONS: Regulated by ERRγ, an optimistic therapeutic target, the CD47-HCK-LGALS9 axis modulated cellular proliferation-immunosuppression coupling in early-stage EC.
Breast cancer is a highly heterogeneous disease characterized by diverse molecular subtypes and complex pathogenesis. Recent advances in epigenetics have unveiled the crucial roles of lysine demethylases (KDMs) in modula...Breast cancer is a highly heterogeneous disease characterized by diverse molecular subtypes and complex pathogenesis. Recent advances in epigenetics have unveiled the crucial roles of lysine demethylases (KDMs) in modulating gene expression and chromatin dynamics, thereby influencing breast cancer progression, including metastasis, and therapeutic resistance. KDMs, which remove methyl groups from histone lysine residues, are mainly categorized into seven subfamilies (KDM1-7) based on their catalytic mechanisms and substrate specificities. Meanwhile, each subfamily exhibits distinct roles in breast cancer, ranging from transcriptional regulation and chromatin remodeling to interactions with non-histone proteins. Notably, KDMs exhibit subtype-specific functions in breast cancer. KDMs are also implicated in various hallmarks of breast cancer, including DNA damage response, cell cycle regulation, stemness maintenance, metabolic reprogramming, and modulation of the tumor microenvironment. KDMs represent promising targets for overcoming therapeutic resistance in breast cancer. Inhibitors targeting KDMs have shown potential to enhance the efficacy of endocrine therapy, chemotherapy, and targeted therapy by modulating oncogenic signaling pathways. The KDM family members are intricately involved in the molecular pathogenesis of breast cancer, offering a rich landscape for therapeutic intervention. This review summarizes the multifaceted molecular mechanisms and biological functions of KDMs in breast cancer, highlighting their potential as therapeutic targets.
BACKGROUND: The RNA methyltransferase METTL3 as a key regulator of acute myeloid leukemia (AML) contributes to malignant transformation. Chromatin topologically associating domains (TADs) are critical for maintaining AML...BACKGROUND: The RNA methyltransferase METTL3 as a key regulator of acute myeloid leukemia (AML) contributes to malignant transformation. Chromatin topologically associating domains (TADs) are critical for maintaining AML genome integrity, but the mechanism by which METTL3 facilitates TADs integrity in AML progression remains unclear. METHODS: To determine whether METTL3 is transcriptionally activated by MLL in MLL-rearranged (MLLr+) AML cells, we analyzed MLL ChIP-seq data. Additionally, we performed a multi-omics approach—including RNA-seq, immunoprecipitation-mass spectrometry (IP-MS) for METTL3 and YTHDC1, DNA: RNA hybrid immunoprecipitation sequencing (DRIP-seq), METTL3 ChIP-seq, CTCF ChIP-seq, H3K4me3 and H3K27ac ChIP-seq—to delineate the functional interplay among METTL3-YTHDC1 axis, R-loops, and CTCF in the MLLr + AML genome. Furthermore, METTL3-RIPseq, YTHDC1 RIPseq, CTCF RIPseq, m6A-seq, and Hi-C-seq assays were conducted to elucidate the function of the METTL3-YTHDC1 axis-mediated m6A modification of architectural RNAs (arcRNAs) in regulating CTCF-dependent TAD boundary activity. RESULTS: METTL3 is transcriptionally activated by MLL and forms a complex with YTHDC1 and CTCF, colocalizing at promoters and enhancers in MLLr + AML cells. METTL3 depletion disrupts CTCF binding sites (CBSs) and reduces chromatin accessibility at key leukemic genes (e.g. MYB and RUNX1). Hi-C analysis further reveals that YTHDC1 loss compromises CTCF-dependent 3D genome organization. METTL3-mediated m6A modification stabilizes arcRNAs and R-loops, which are crucial for maintaining TAD integrity at leukemic loci. Mechanistically, YTHDC1 recognizes m6A-modified arcRNAs (e.g. MALAT1) to enhance R-loop formation, thereby sustaining CTCF-mediated TAD activity in the MLLr + AML genome. CONCLUSIONS: Our study identifies the METTL3-YTHDC1-CTCF axis as a critical regulator of AML signature gene expression by orchestrating 3D genome organization. These findings provide novel insights into AML pathogenesis and reveal new therapeutic targets for this kind of aggressive disease.
Nieto-Sanchez A, Martinez-Lage M, Puig-Serra P
… +18 more, Carpintero S, Alonso-Yanez A, Ojeda-Walczuk P, Ibañez-Navarro M, Pita G, Moya FJ, Moreno C, Martin MC, Alonso R, Nuñez-Torres R, Sanchez-Arevalo Lobo VJ, Alonso-Guirado L, Malats N, Gonzalez-Neira A, Fernandez L, Roda-Navarro P, Torres-Ruiz R, Rodriguez-Perales S
Oncogene amplifications fuel some of the most lethal, therapy‑refractory cancers, yet remain clinically untargeted. We report a single‑guide CRISPR/Cas9 strategy that converts the sheer copy‑number excess of oncogene amp...Oncogene amplifications fuel some of the most lethal, therapy‑refractory cancers, yet remain clinically untargeted. We report a single‑guide CRISPR/Cas9 strategy that converts the sheer copy‑number excess of oncogene amplicons into an Achilles' heel. A solitary intronic double‑strand break is innocuous in diploid genomes but collapses oncogene amplification‑positive cells across neuroblastoma, small‑cell lung and colorectal carcinoma models, driving > 90% loss of viability, G₂/M blockade and catastrophic DNA‑damage signalling. Amplified‑locus cleavage rewires transcription toward cell death activation, necroptosis and cGAS-STING-mediated immunogenic cell death, enabling dendritic‑cell cross‑priming and T‑cell activation and proliferation. In xenografts, delivery of the intronic sgRNA shrinks tumours by 90%, prolongs survival and remodels the innate tumour microenvironment. Deep sequencing confirms negligible off‑target editing, and combination with doxorubicin achieves supra‑additive killing. These findings establish amplification density, not sequence content, as a tractable, tumour‑exclusive target and unveil a dual‑action platform that is simultaneously cytotoxic and immunostimulatory. Editing of tumor amplifications therefore offers a blueprint for translating copy‑number aberrations into precision genome‑editing therapies for treatment‑resistant cancers.
Liu XY, Sui XY, Xu Y
… +22 more, Yang F, Wu SY, Zhu XZ, Zuo K, Cao SW, Jin X, Chen L, Ma LX, Zhang WJ, Ye FG, Qu FL, Ma D, Xiao Y, Di GH, Liu GY, Yu KD, Wu J, Hu X, Jiang YZ, Wang ZH, Shao ZM, Fan L
BACKGROUND: While immunotherapy-chemotherapy combinations are approved for programmed death-ligand 1 (PD-L1)-positive advanced triple-negative breast cancer (TNBC), the therapeutic potential of sitravatinib-enhanced immu...BACKGROUND: While immunotherapy-chemotherapy combinations are approved for programmed death-ligand 1 (PD-L1)-positive advanced triple-negative breast cancer (TNBC), the therapeutic potential of sitravatinib-enhanced immunotherapy remains unexplored. METHODS: This multi-cohort, single-arm study enrolled 67 patients with locally recurrent/metastatic TNBC. Cohorts A (n = 21) and B (n = 40) received sitravatinib 70 mg or 100 mg once daily plus tislelizumab, with 38/67 participants having ≥ 1 prior systemic therapy. The primary endpoint was confirmed objective response rate (ORR); secondary endpoints included median progression-free survival (PFS) and safety. Multi-omics analyses including single-cell sequencing and genomic profiling were performed on tumor samples to identify biomarkers linked to treatment response. RESULTS: Confirmed ORR was 38.1% (8/21) in Cohort A and 50.0% (20/40) in Cohort B. Median PFS was 8.2 months (Cohort A) and 5.4 months (Cohort B). Notably, 95.3% (41/43) of previously treated patients had PD-L1 combined positive score (CPS) < 10. No grade 4/5 treatment-related adverse events occurred. Biomarker analysis revealed Th17 cell infiltration and TYRO3/AXL/MERTK (TAM) pathway activation correlated with response, while FAM47C mutations and LSM1+ cancer-associated fibroblasts were enriched in non-responders. Post-treatment TP53 mutation clearance and increased CD8+ T cell proportions predicted improved outcomes. CONCLUSIONS: Sitravatinib plus tislelizumab demonstrates promising efficacy and safety as a chemo-free regimen for metastatic TNBC, including PD-L1-negative tumors. Biomarkers such as Th17 cell infiltration, TAM signaling, and TP53 mutation dynamics may guide patient selection. These findings support further validation of this combination in PD-L1-negative TNBC and highlight the role of multi-omics in optimizing immunotherapy strategies. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04734262.
Advancements in genetic engineering and synthetic biology have markedly accelerated the development and application of chimeric antigen receptor T (CAR-T) cell therapy for cancer treatment. Despite substantial progress,...Advancements in genetic engineering and synthetic biology have markedly accelerated the development and application of chimeric antigen receptor T (CAR-T) cell therapy for cancer treatment. Despite substantial progress, the treatment of solid tumors remains challenging, with suboptimal clinical outcomes and significant unmet needs. To address these ongoing challenges, considerable efforts are being made to enhance the safety, efficacy, and overall applicability of CAR-T cells therapy. This review outlines the key tumor features that impede CAR-T efficacy, focusing on intrinsic tumor factors and the influence of the microenvironment. We then provide a comprehensive overview of the promising next-generation CAR-T designs and discuss the combinatorial approaches aimed at improving antigen recognition, functional adaptability, and antitumor response, thereby expanding the therapeutic impact of CAR-T cells in solid-tumor settings.
The tumor microenvironment (TME) is increasingly recognized as a critical modulator of the initiation, progression, metastasis, and therapeutic resistance of various cancers. Cancer-associated fibroblasts (CAFs), the pre...The tumor microenvironment (TME) is increasingly recognized as a critical modulator of the initiation, progression, metastasis, and therapeutic resistance of various cancers. Cancer-associated fibroblasts (CAFs), the predominant stromal cell population within the TME, play pivotal roles in these processes through their remarkable phenotypic and functional heterogeneity. Emerging evidence underscores the diversity in the origins, phenotypes, and functions of CAFs, highlighting their ability to adaptively influence tumor biology in a context-dependent manner. CAFs facilitate cancer malignancy via multiple interconnected mechanisms, including the secretion of soluble bioactive factors, the release of exosomes, the metabolic reprogramming of tumor cells, the remodeling of the extracellular matrix (ECM), and the modulation of the immune microenvironment. CAFs have emerged as attractive and viable therapeutic targets. Recent efforts have focused on developing therapies that disrupt the protumorigenic activities of CAFs or reprogram them toward tumor-suppressive phenotypes. Several of these strategies have shown promise and are advancing into clinical trials. In this review, we comprehensively discuss recent advancements in our understanding of the heterogeneity of CAFs, elucidate their multifaceted interactions within the TME, and explore novel therapeutic strategies targeting CAFs across various cancer types. Our review aims to foster the translation of preclinical insights into clinically effective interventions targeting CAFs.
Rasbach E, Migayron L, Brandenburg A
… +27 more, Singh P, Martins C, Kassem A, Karkempetzaki AI, Suessner N, Kulcsar Z, Riopedre J, Silva M, Zhen E, Xu S, Mucciarone K, Holzgruber J, Williams JB, Birgin E, Levesque MP, Martínez-Gómez JM, Dummer R, Landsberg J, Lian CG, Murphy GF, Berdan EL, Sui SH, Kupper TS, Rahbari NN, Lee N, Barthel SR, Schatton T
BACKGROUND: ITGB2 is a critical integrin mediator of immune cell activation and trafficking. Its expression has been claimed as exclusive to hematopoietic cells. Consequently, the significance of cancer cell-intrinsic IT...BACKGROUND: ITGB2 is a critical integrin mediator of immune cell activation and trafficking. Its expression has been claimed as exclusive to hematopoietic cells. Consequently, the significance of cancer cell-intrinsic ITGB2 in solid tumor progression and therapy has not been rigorously evaluated. METHODS: We leveraged single-cell and bulk RNA sequencing, real-time quantitative PCR, multiplex immunofluorescence, flow cytometry, immunoblotting, and intercellular adhesion molecule (ICAM)-1-dependent adhesion and proliferation assays to uncover melanoma cell-intrinsic ITGB2 functional expression, association with clinical tumor progression, activation, protumorigenic signaling, adhesive and proliferative functions utilizing patient melanoma biospecimens, established human and murine melanoma lines. In vivo tumorigenicity studies in immunocompromised NOD/SCID interleukin-2 receptor γ chain null (NSG), immunocompetent wildtype, and Icam1 knockout (KO) C57BL/6 mice were performed to dissect melanoma-ITGB2 downstream pathway activity and functions in tumor growth and metastasis. The cancer cell-intrinsic ITGB2 axis was targeted using CRISPR/Cas9-based Itgb2 KO, blocking ITGB2 antibodies, ITGB2-activating CD44 crosslinking, and pharmacologic inhibition of ITGB2-dependent Wnt signaling using LGK974, zamaporvint, and FDA-approved pyrvinium pamoate repurposed for cancer therapy. RESULTS: This work demonstrates nonhematopoietic expression and protumorigenic functions of ITGB2 intrinsic to melanoma cells. Tumor cell-ITGB2 mediated adhesion to ICAM-1, promoted cancer progression in preclinical melanoma models, was enriched in clinical metastatic versus primary melanomas or benign nevi, and predicted sentinel lymph node metastasis in patients with primary disease. Consistently, inhibition of melanoma cell-intrinsic ITGB2 using blocking antibodies or Itgb2 gene KO potently suppressed ICAM-1-mediated melanoma cell adhesion, tumor growth, and metastatic dissemination. Melanoma cell-ITGB2:ICAM-1 interaction activated downstream Wnt signaling, the pharmacologic inhibition of which suppressed melanoma-ITGB2-mediated tumorigenesis. CONCLUSIONS: This work overturns the longstanding paradigm that ITGB2 is restricted to leukocytes by discovering a tumor cell-intrinsic ITGB2:ICAM-1:Wnt protumorigenic axis as a bona fide cancer therapeutic target in melanoma.
BACKGROUND: Osteosarcoma demonstrates limited responsiveness to PD-1 blockade, largely due to its immunosuppressive tumor microenvironment (TME). The specific mechanisms by which cancer-associated fibroblasts (CAFs) cont...BACKGROUND: Osteosarcoma demonstrates limited responsiveness to PD-1 blockade, largely due to its immunosuppressive tumor microenvironment (TME). The specific mechanisms by which cancer-associated fibroblasts (CAFs) contribute to immunosuppression in osteosarcoma are not fully understood. METHODS: We performed single-cell RNA sequencing (scRNA-seq) on osteosarcoma tissues from patients treated with neoadjuvant chemotherapy and anti-PD-1 therapy to investigate the tumor microenvironment. Cellular composition, gene expression programs, and signaling pathways were analyzed. Functional assays, pull-down and PLA-flow binding validation, and in vivo mouse models were used to dissect the mechanisms by which CAF-derived factors influence CD8⁺ T cell function and contribute to immunotherapy response. RESULTS: We identified a subpopulation of CD36⁺ CAFs, characterized by adaptive uptake of oxidized low-density lipoprotein (OxLDL) and activation of the PPARG-FABP4 axis. This metabolic program promoted ANGPTL4 secretion, which bound integrin on CD8⁺ T cells and activated the JAK2-STAT3 pathway, leading to T cell exhaustion and impaired effector function. In vivo, administration of VitE effectively scavenged OxLDL, reprogrammed the TME, enhanced CD8⁺ T cell infiltration, and synergized with PD-1 blockade to improve tumor control. CONCLUSIONS: CD36⁺ CAFs drive immunosuppressive metabolic reprogramming via the OxLDL-PPARG-ANGPTL4 axis, promoting CD8⁺ T cell exhaustion and resistance to immunotherapy in osteosarcoma. Targeting this pathway with VitE alleviated CAF-mediated immune suppression and enhanced PD-1 blockade responses in preclinical models, providing a rationale for metabolism-based combinatorial strategies in osteosarcoma.
The efficacy of immune checkpoint inhibitors (ICIs) in microsatellite stable colorectal cancer (MSS CRC) remains limited, highlighting an urgent need for predictive biomarkers. Through multi-omics analysis, we identified...The efficacy of immune checkpoint inhibitors (ICIs) in microsatellite stable colorectal cancer (MSS CRC) remains limited, highlighting an urgent need for predictive biomarkers. Through multi-omics analysis, we identified two novel MSS CRC subtypes, termed DUB-H and DUB-L. The DUB-L subtype exhibited an inflamed tumor immune microenvironment, a superior response to immune therapy, and better recurrence-free survival (RFS) compared to DUB-H. The classifier gene USP7 was selected as a gene of interest due to its specific expression profile, which is highly expressed in MSS CRC but not in microsatellite instability-high (MSI-H) tumors, and strongly correlated with suppressed immune infiltration. Large-scale clinical analyses confirmed associations between high USP7 expression, microsatellite stability, specific consensus molecular subtypes (CMS), and unfavorable prognosis. Single-cell analysis and multiplex immunofluorescence validated an immune-desert phenotype in USP7-high MSS tumors. Mechanistically, USP7 knockdown in MSS CRC cells enhances the secretion of T-cell-recruiting chemokines (CXCL9/10/11), promoting CD8⁺ T cell recruitment and cytotoxicity in vitro. In vivo experiments demonstrated that USP7 blockade enhanced the efficacy of anti-PD-1 treatment in MSS CRC models by remodeling the tumor immune microenvironment, increasing infiltration and function of CD8⁺ T and NK cells. Consistently, low USP7 expression is associated with a better response to anti-PD-1 therapy. Overall, we propose a novel DUB-based classification system for MSS CRC and demonstrate that targeting USP7 may overcome immunotherapy resistance by converting immunologically “cold” tumors into “hot” ones.
Metabolic reprogramming of amino acids has been recognized as a significant characteristic in various types of cancers. Numerous studies have indicated that the metabolic reprogramming of amino acids in tumors significan...Metabolic reprogramming of amino acids has been recognized as a significant characteristic in various types of cancers. Numerous studies have indicated that the metabolic reprogramming of amino acids in tumors significantly supports certain malignant behaviors, including tumor proliferation, survival, invasion, and even immune escape. Amino acids can provide biomolecules such as nucleotides and glutathione (GSH) for tumors, and the bioavailability of amino acids influences tumor progression. Meanwhile, as essential metabolites, amino acids are closely associated with immune cell activation and can contribute to tumor immune processes by modulating the function of immune cells. Thus, targeting amino acids metabolism has emerged as a promising therapeutic strategy. Herein, we provide an overview of the effects of amino acids on the central carbon cycle and autophagy. We also provide an in-depth review of potential therapies for cancer treatment associated with amino acids, including metabolic enzymes of amino acids, dietary therapy of amino acids, and so on. Furthermore, we summarize some current nano-systems relevant to amino acids. This review aims to offer a theoretical foundation for understanding amino acids metabolism in cancer and identifying potential therapeutic strategies.