Search Results (62)

Background/Objectives: Subcutaneous tumor models are widely used in colorectal cancer (CRC) research due to their experimental accessibility; however, the spatial organization and regulatory mechanisms of their tumor microenvironment remain poorly understood. Methods: Here, we applied spatial transcriptomics to systematically characterize spatial heterogeneity within MC38 subcutaneous tumors in a syngeneic mouse model. Results: We identified two spatially distinct tumor zones, partitioned by cancer-associated fibroblasts (CAFs), that differ markedly in cellular composition, oncogenic signaling, immune infiltration, and metabolic states. One zone exhibited features of TGF-β-driven extracellular matrix remodeling, immune exclusion, and hyperproliferative metabolism, while the other was enriched for immunosuppressive macrophages, metabolic reprogramming via PPAR and AMPK pathways, and high-risk cell populations. Spatially resolved cell–cell communication networks further revealed zone-specific ligand–receptor interactions—such as ANGPTL4–SDC2 and PROS1–AXL—that underpin stromal remodeling and immune evasion and are associated with patient prognosis. Conclusions: Collectively, our study uncovers how region-specific cellular ecosystems and intercellular crosstalk establish prognostically divergent niches within subcutaneous CRC tumors, offering insights into spatially guided therapeutic strategies. Full article

High-grade serous ovarian cancer (HGSOC) is an aggressive gynecological malignancy characterized by intraperitoneal spread and chemotherapy resistance. Chemotherapies have demonstrated limited effectiveness in HGSOC, underscoring the urgent need to evaluate how the tumor microenvironment (TME) was reshaped by chemotherapy in different sites of tumor foci. In this study, we performed single-cell transcriptomic analysis to explore the TME in samples obtained from various sites of tumor foci, with or without the history of Neoadjuvant chemotherapy (NACT). We discovered that chemotherapy reshaped the tumor immune microenvironment, evident through the reduction in human leukocyte antigen (HLA) diversity and the increase in PDCD1/CD274 in CD8_ANXA1, LAMP3+ dendritic cell (DC_LAMP3), and EREG+ monocytes (mono_EREG). Moreover, cancer.cell.2, cancer-associated C3+ fibroblasts (CAF_C3), and Fibrocyte_CD34, which are prone to accumulate in the metastatic site and post-NACT group, harbored poor clinical outcome, reflected in the immune exclusion and tumor progression signaling. Cell–cell communication identified a stronger interaction between cancer.cell.2 and CAF_C3, as well as Fibrocyte_CD34, in post-NACT samples, indicating that chemotherapy reshapes pre-existing cell clusters in a site-dependent manner. Our findings suggest that chemotherapy and sites of foci were critical for the transcriptional reprogramming of pre-existed cell clusters. Our study offers a single-cell phenotype data substrate from which to develop a personalized combination of chemotherapy and immunotherapy. Full article

Tumor cells often exhibit mitochondrial dysfunction and a pronounced glycolytic shift (the “Warburg effect”) that alters the tumor microenvironment. These metabolic changes, including mitochondrial DNA mutations and impaired oxidative phosphorylation, confer survival advantages and can reduce sensitivity to chemotherapeutics such as paclitaxel. In hypoxic environments, cancer cells upregulate glycolysis via HIF-1α, consequently lowering the extracellular pH through lactate secretion, which is associated with resistance to paclitaxel. Likewise, cancer-associated fibroblasts and immune cells undergo metabolic reprogramming in the tumor microenvironment. Glycolytic CAFs produce lactate and pyruvate that fuel tumor cells, reinforcing drug resistance, and tumor-driven polarization of macrophages toward an immunosuppressive M2 phenotype further impairs the anti-tumor response. Here, we review recent findings on how these metabolic adaptations attenuate paclitaxel efficacy and discuss strategies to overcome resistance. We highlight 15 key studies that reported cancer types, metabolic alterations, molecular targets, and outcomes related to paclitaxel response. Overall, the data suggest that targeting metabolic vulnerabilities, for example, by inhibiting glycolysis (HK2, PGAM1, and PDK) or modulating mitochondrial function, may restore paclitaxel sensitivity. Understanding metabolic crosstalk in the tumor microenvironment provides a basis for combined therapies that improve outcomes in paclitaxel-resistant cancers. Full article

In vitro tissue models offer a flexible complementary study system for use alongside in vivo human tissue samples. Achieving accurate in vitro models relies on combining appropriate scaffolds, growth factors and cell populations to recreate human tissue complexity. Balancing a consistent cell supply with the creation of healthy tissue models can be challenging; established cell lines are often cancerous, with altered cellular function compared to healthy populations, and primary cells require repeated isolation, with associated batch-to-batch variation. Pluripotent stem cell-derived populations offer a consistent supply, as well as the ability to model disease phenotypes through cell reprogramming using patient-derived cells. In this study, we have used an induced pluripotent stem cell-derived fibroblast population to develop a dermal equivalent model. These cells form a consistent tissue construct with a structure and composition similar to primary fibroblast controls, which are able to support an overlying epidermis. The resultant full-thickness skin model demonstrates the expression of various key skin-related markers, correctly localised within the organised epidermis, notably improving on previous models of a similar nature. Providing proof of concept using an established in vitro protocol, this study paves the way for future work developing consistent, customised, full-thickness human skin equivalents using iPSC-derived populations. Full article

The tumor microenvironment (TME) is crucial for the onset, development, and resistance to treatment of lung cancer. The tumor microenvironment consisting of a complex array of immune cells, fibroblasts, endothelial cells, extracellular matrix elements, and signaling molecules, facilitates tumor growth and spread while inhibiting the body’s antitumor immune response. In lung cancer, tumor-associated macrophages, cancer-associated fibroblasts, mast cells, and dendritic cells interact through cytokines, chemokines, growth factors, and matrix metalloproteinases to create an immunosuppressive and proangiogenic milieu. Hypoxic conditions within the TME further enhance cancer cell adaptability through hypoxia-inducible factors (HIFs), promoting epithelial–mesenchymal transition, immune evasion, and metastasis. Moreover, miRNAs have emerged as key regulators of gene expression within the TME, offering novel insights into tumor behavior and potential therapeutic targets. Targeting dynamic interactions within the TME, particularly through the modulation of immune responses, angiogenesis, and stromal remodeling, offers promising avenues for precision pharmacological approaches. This review covers the current understanding of the lung TME, highlighting its impact on cancer pathophysiology and treatment strategies. Understanding and therapeutically reprogramming the TME may pave the way for personalized and more effective interventions for lung cancer treatment. Full article

We have previously shown that in cancer patients, free methylglyoxal (MG), a side-product of glycolysis, is recovered from tumors at significantly higher levels than from their corresponding non-cancerous tissues. We also recently confirmed our initial experimental finding that in these patients, free MG peripheral blood levels correlate positively with tumor growth, making free MG levels a new metabolic biomarker of tumor growth of interest to detect cancer and clinically follow cancer patients with no available biomarkers. Now we measure free MG and lactate produced by different cancer and normal cells cultured at low or high glucose concentration and in normoxic or hypoxic conditions to question whether cancer cells and non-cancer cells in tumors produce and release free MG and lactate. Surprisingly, we found that normal fibroblastic and endothelial cell lines grown in normoxic conditions produce and release high free MG levels, which we confirmed for non-transformed normal fibroblasts, albeit at significantly lower levels. Cancer cells generally significantly increased their free MG production and release when cultured in high glucose concentration, while normal cells generally did not. Furthermore, in normoxic conditions, normal fibroblastic cells, in addition to free MG, may produce and release lactate. From this data, we propose that in malignant tumors, both cancer and fibroblastic stromal cells may contribute to tumor growth and development by producing via glycolysis both free MG and D-lactate, which, in addition to L-lactate, may be part of the core hallmark of cell metabolic reprogramming in cancer. Full article

Background/Objectives: Mesenchymal stem cells (MSCs) possess immunomodulatory properties, tumor-homing, and low immunogenicity, making them attractive for cell-based cancer therapies, but their role in colorectal cancer (CRC) remains controversial. The MSC1 phenotype, a pro-inflammatory, tumor-suppressive state induced by short-term, low-dose LPS activation via TLR4, has shown therapeutic promise but remains poorly characterized in CRC. We aimed to elucidate MSC1’s tumor-suppressive mechanisms and validate its activity against CRC cells using an integrated bioinformatics and in vitro approach. Methods: We constructed a high-confidence protein-protein interaction (PPI) network in Wharton’s jelly-derived MSCs (WJ-MSCs) following TLR4 activation to uncover enriched signaling pathways, transcriptional regulators, and secreted factors. Functional and transcriptional enrichment analyses pinpointed key mechanisms. We then co-cultured MSC1 cells with CRC cells to assess effects on proliferation and metabolism. Results: Network analysis revealed six tumor-suppressive mechanisms of MSC1 cells: (i) Metabolic reprogramming via enhanced glucose and lipid uptake, phosphoinositide signaling, and membrane/protein recycling, (ii) Robust antioxidant defenses, including SOS signaling and system xc⁻, (iii) Extracellular matrix stabilization and laminin-111–integrin-mediated adhesion, (iv) Secretome with direct anti-cancer effects, (v) Regulation of survival and cancer-associated fibroblasts (CAFs) formation inhibition through balanced proliferation, apoptosis, and epigenetic signals, (vi) Controlled pro-inflammatory signaling with anti-inflammatory feedback. In vitro, MSC1 cells significantly suppressed CRC cell proliferation and metabolic activity versus controls. Conclusions: This study provides the first mechanistic map of MSC1’s tumor-suppressive functions in CRC, extending beyond immunomodulation to include metabolic competition, ECM stabilization, and anti-cancer secretome activity. These findings establish MSC1 cells as a novel therapeutic strategy for CRC in cell-based cancer therapies. Full article

Lactate is a key oncometabolite that plays a critical role in modulating the behavior and function of both tumor cells and tumor-associated stromal cells within the tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs), as essential stromal components, engage in dynamic crosstalk with tumor cells through lactate-mediated signaling pathways. Elevated lactate levels in the TME primarily originate from metabolic reprogramming in tumor cells and CAFs. Notably, tumor-derived lactate not only promotes basement membrane remodeling and epithelial–mesenchymal transition (EMT) in CAFs but also influences their functional phenotype. Conversely, CAF-secreted lactate significantly contributes to tumor progression. Therapeutic strategies targeting lactate transport and metabolism—particularly through the inhibition of monocarboxylate transporters (MCTs) and lactate dehydrogenase (LDH)—have emerged as promising approaches in cancer treatment. This review summarizes the multifaceted roles of lactate and lactylation, elucidates the molecular mechanisms underlying lactate-mediated tumor–CAF crosstalk, and explores potential therapeutic interventions targeting lactate metabolism and CAFs. Full article

Hepatocellular carcinoma (HCC) is a major cause of cancer-related mortality worldwide. Conventional therapies are frequently limited by tumor heterogeneity and the immunosuppressive tumor microenvironment (TME). Dendritic cells (DCs), central to orchestrating antitumor immunity, have become key targets for HCC immunotherapy. This review examines the biological functions of DC subsets (cDC1, cDC2, pDC, and moDC) and their roles in initiating and modulating immune responses against HCC. We detail the mechanisms underlying DC impairment within the TME, including suppression by regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), and cancer-associated fibroblasts (CAFs). Additionally, we discuss novel DC-based therapeutic strategies, such as DC-based vaccines designed to enhance antigen presentation and T cell activation. Combining DC vaccines with immune checkpoint inhibitors (ICIs), including PD-1/PD-L1 and CTLA-4 blockers, demonstrates synergistic effects that can overcome immune evasion and improve clinical outcomes. Despite progress, challenges related to DC subset heterogeneity, TME complexity, and patient variability require the further optimization and personalization of DC-based therapies. Future research should focus on refining these strategies, leveraging advanced technologies like genomic profiling and artificial intelligence, to maximize therapeutic efficacy and revolutionize HCC treatment. By restoring DC function and reprogramming the TME, DC-based immunotherapy holds immense potential to transform the management of HCC and improve patient survival. Full article

Background: The interaction between cancer cells and cancer-associated fibroblasts (CAFs) is a key determinant of the rapid progression, high invasiveness, and chemoresistance of aggressive desmoplastic cancers such as pancreatic ductal adenocarcinoma (PDAC). Tumor cells are known to reprogram fibroblasts into CAFs by secreting transforming growth factor beta (TGF-β), amongst other cytokines. In turn, CAFs produce soluble factors that promote tumor-cell invasiveness and chemoresistance, including TGF-β itself, which has a major role in myofibroblastic CAFs. Such a high level of complexity has hampered progress toward a clear view of the TGFβ signaling loop between stromal fibroblasts and PDAC cells. Methods: Here, we tackled this issue by using co-culture settings that allow paracrine signaling alone (transwell systems) or paracrine and contact-mediated signaling (3D spheroids). Results: We found that TGF-β is critically involved in the activation of normal human fibroblasts into alpha-smooth muscle actin (α-SMA)-positive CAFs. The TGF-β released by CAFs accounted for the enhanced proliferation and resistance to gemcitabine of PDAC cells. This was accompanied by a partial epithelial-to-mesenchymal transition in PDAC cells, with no increase in their migratory abilities. Nevertheless, 3D heterospheroids comprising PDAC cells and fibroblasts allowed monitoring the pro-invasive effects of CAFs on cancer cells, possibly due to combined paracrine and physical contact-mediated signals. Conclusions: We conclude that TGF-β is only one of the players that mediates the communication between PDAC cells and fibroblasts and controls the acquisition of aggressive phenotypes. Hence, these advanced in vitro models may be exploited to further investigate these events and to design innovative anti-PDAC therapies. Full article

Adipose-derived stromal cells (ASCs) and cancer-associated fibroblasts (CAFs) play pivotal roles in the tumor microenvironment (TME), significantly influencing cancer progression and metastasis. This review explores the plasticity of ASCs, which can transdifferentiate into CAFs under the influence of tumor-derived signals, thus enhancing their secretion of extracellular matrix components and pro-inflammatory cytokines that promote tumorigenesis. We discuss the critical process of the epithelial-to-mesenchymal transition (EMT) facilitated by ASCs and CAFs, highlighting its implications for increased invasiveness and therapeutic resistance in cancer cells. Key signaling pathways, including the transforming growth factor-β (TGF-β), Wnt/β-catenin, and Notch, are examined for their roles in regulating EMT and CAF activation. Furthermore, we address the impact of epigenetic modifications on ASC and CAF functionality, emphasizing recent advances in targeting these modifications to inhibit their pro-tumorigenic effects. This review also considers the metabolic reprogramming of ASCs and CAFs, which supports their tumor-promoting activities through enhanced glycolytic activity and lactate production. Finally, we outline potential therapeutic strategies aimed at disrupting the interactions between ASCs, CAFs, and tumor cells, including targeted inhibitors of key signaling pathways and innovative immunotherapy approaches. By understanding the complex roles of ASCs and CAFs within the TME, this review aims to identify new therapeutic opportunities that could improve patient outcomes in cancer treatment. Full article

Background: Idiopathic pulmonary fibrosis (IPF) leads to excessive fibrous tissue in the lungs, increasing the risk of lung cancer (LC) due to heightened fibroblast activity. Advances in nucleotide point mutation studies offer insights into fibrosis-to-cancer transitions. Methods: A two-sample Mendelian randomization (TSMR) approach was used to explore the causal relationship between IPF and LC. A weighted gene co-expression network analysis (WGCNA) identified shared gene modules related to immunogenic cell death (ICD) from transcriptomic datasets. Machine learning selected key genes, and a multi-layer perceptron (MLP) model was developed for IPF prediction and diagnosis. SMR and PheWAS were used to assess the expression of key genes concerning IPF risk. The impact of core genes on immune cells in the IPF microenvironment was explored, and in vivo experiments were conducted to examine the progression from IPF to LC. Results: The TSMR approach indicated a genetic predisposition for IPF progressing to LC. The predictive model, which includes eight ICD key genes, demonstrated a strong predictive capability (AUC = 0.839). The SMR analysis revealed that the elevated expression of MS4A4A was associated with an increased risk of IPF (OR = 1.275, 95% CI: 1.029–1.579; p = 0.026). The PheWAS did not identify any significant traits linked to MS4A4A expression. The rs9265808 locus in MS4A4A was identified as a susceptibility site for the progression of IPF to LC, with mutations potentially reprogramming lung neutrophils and increasing the LC risk. In vivo studies suggested MS4A4A as a promising therapeutic target. Conclusions: A causal link between IPF and LC was established, an effective prediction model was developed, and MS4A4A was highlighted as a therapeutic target to prevent IPF from progressing to LC. Full article

Cancer-associated fibroblast (CAF) composition within the same organ varies across different cancer subtypes. Distinct CAF subtypes exhibit unique features due to interactions with immune cells and the tumor microenvironment. However, data on CAF subtypes in individuals with vestibular schwannoma (VS) are lacking. Therefore, we aimed to distinguish CAF subtypes at the single-cell level, investigate how stem-like CAF characteristics influence the tumor immune microenvironment, and identify CAF subtype-specific metabolic reprogramming pathways that contribute to tumor development. Data were analyzed from three patients with VS, encompassing 33,081 single cells, one bulk transcriptome cohort, and The Cancer Genome Atlas Pan-Cancer database (RNA sequencing and clinical data). Our findings revealed that antigen-presenting CAFs are linked to substantially heightened immune activity, supported by metabolic reprogramming, which differs from tumorigenesis. High expression of the stem-like CAF gene signature correlated with poor prognosis in low-grade gliomas within the pan-cancer database. This is the first study to classify CAF subtypes in VS patients and identify a therapeutic vulnerability biomarker by developing a stem-like CAF gene signature. Personalized treatments tailored to individual patients show promise in advancing precision medicine. Full article

One aspect of ovarian tumorigenesis which is still poorly understood is the tumor–stroma interaction, which plays a major role in chemoresistance and tumor progression. Cancer-associated fibroblasts (CAFs), the most abundant stromal cell type in the tumor microenvironment, influence tumor growth, metabolism, metastasis, and response to therapy, making them attractive targets for anti-cancer treatment. Unraveling the mechanisms involved in CAFs activation and maintenance is therefore crucial for the improvement of therapy efficacy. Here, we report that CAFs phenoconversion relies on the glucose-dependent inhibition of autophagy. We show that ovarian cancer cell-conditioning medium induces a metabolic reprogramming towards the CAF-phenotype that requires the autophagy-dependent glycolytic shift. In fact, 2-deoxy-D-glucose (2DG) strongly hampers such phenoconversion and, most importantly, induces the phenoreversion of CAFs into quiescent fibroblasts. Moreover, pharmacological inhibition (by proline) or autophagy gene knockdown (by siBECN1 or siATG7) promotes, while autophagy induction (by either 2DG or rapamycin) counteracts, the metabolic rewiring induced by the ovarian cancer cell secretome. Notably, the nutraceutical resveratrol (RV), known to inhibit glucose metabolism and to induce autophagy, promotes the phenoreversion of CAFs into normal fibroblasts even in the presence of ovarian cancer cell-conditioning medium. Overall, our data support the view of testing autophagy inducers for targeting the tumor-promoting stroma as an adjuvant strategy to improve therapy success rates, especially for tumors with a highly desmoplastic stroma, like ovarian cancer. Full article

CYLD is a tumor suppressor gene coding for a deubiquitinating enzyme that has a critical regulatory function in a variety of signaling pathways and biological processes involved in cancer development and progression, many of which are also key modulators of somatic cell reprogramming. Nevertheless, the potential role of CYLD in this process has not been studied. With the dual aim of investigating the involvement of CYLD in reprogramming and developing a better understanding of the intricate regulatory system governing this process, we reprogrammed control (CYLD^WT/WT) and CYLD DUB-deficient (CYLD^Δ9/Δ9) mouse embryonic fibroblasts (MEFs) into induced pluripotent stem cells (iPSCs) through ectopic overexpression of the Yamanaka factors (Oct3/4, Sox2, Klf4, c-myc). CYLD DUB deficiency led to significantly reduced reprogramming efficiency and slower early reprogramming kinetics. The introduction of WT CYLD to CYLD^Δ9/Δ9 MEFs rescued the phenotype. Nevertheless, CYLD DUB-deficient cells were capable of establishing induced pluripotent colonies with full spontaneous differentiation potential of the three germ layers. Whole proteome analysis (Data are available via ProteomeXchange with identifier PXD044220) revealed that the mesenchymal-to-epithelial transition (MET) during the early reprogramming stages was disrupted in CYLD^Δ9/Δ9 MEFs. Interestingly, differentially enriched pathways revealed that the primary processes affected by CYLD DUB deficiency were associated with the organization of the extracellular matrix and several metabolic pathways. Our findings not only establish for the first time CYLD’s significance as a regulatory component of early reprogramming but also highlight its role as an extracellular matrix regulator, which has profound implications in cancer research. Full article