Modulation Of Microenvironment Research Articles

Hierarchically structured nanofibrous scaffolds spatiotemporally mediate the osteoimmune micro-environment and promote osteogenesis for periodontitis-related alveolar bone regeneration

Periodontitis suffer from inflammation-induced destruction of periodontal tissues, resulting in the serious loss of alveolar bone. Controlling inflammation and promoting bone regeneration are two crucial aspects for periodontitis-related alveolar bone defect treatment. Herein, we developed a hierarchically structured nanofibrous scaffold with a nano-embossed sheath and a bone morphogenetic protein 2-loaded core to match the periodontitis-specific features that spatiotemporally modulated the osteoimmune environment and promoted periodontal bone regeneration. We investigated the potential of this unique scaffold to treat periodontitis-related alveolar bone defects in vivo and in vitro. The results demonstrated that the hierarchically structured scaffold effectively reduced the inflammatory levels in macrophages and enhanced the osteogenic potential of bone mesenchymal stem cells in an inflammatory microenvironment. Moreover, in vivo experiments revealed that the hierarchically structured scaffold significantly ameliorated inflammation in the periodontium and inhibited alveolar bone resorption. Notably, the hierarchically structured scaffold also exhibited a prolonged effect on promoting alveolar bone regeneration. These findings highlight the significant therapeutic potential of hierarchically structured nanofibrous scaffolds for the treatment of periodontitis, and their promising role in the field of periodontal tissue regeneration. Statement of Significance: We present a novel hierarchically structured nanofibrous scaffold of coupling topological and biomolecular signals for precise spatiotemporal modulation of the osteoimmune micro-environment. Specifically, the scaffold was engineered via coaxial electrospinning of the poly(ε-caprolactone) sheath and a BMP-2/polyvinyl alcohol core, followed by surface-directed epitaxial crystallization to generate cyclic nano-lamellar embossment on the sheath. With this unique hierarchical structure, the cyclic nano-lamellar sheath provided a direct nano-topographical cue to alleviate the osteoimmune environment, and the stepwise release of BMP-2 from the core provided a biological cue for bone regeneration. This research underscores the potential of hierarchically structured nanofibrous scaffolds as a promising therapeutic approach for periodontal tissue regeneration and highlights their role in advancing periodontal tissue engineering.

Unraveling the Fundamentals of Axial Coordination FeN4+1 Sites Regulating the Peroxymonosulfate Activation for Fenton-Like Activity.

Precise modulation of the axial coordination microenvironment in single-atom catalysts (SACs) to enhance peroxymonosulfate (PMS) activation represents a promising yet underexplored approach. This study introduces a pyrolysis-free strategy to fabricate SACs with well-defined axial-FeN4+1 coordination structures. By incorporating additional out-of-plane axial nitrogen into well-defined FeN4 active sites within a planar, fully conjugated polyphthalocyanine framework, FeN4+1 configurations are developed that significantly enhance PMS activation. The axial-FeN4+1 catalyst excelled in activating PMS, with a high bisphenol A (BPA) degradation rate of 2.256 min-1, surpassing planar-FeN4/PMS systems by 6.8 times. Theoretical calculations revealed that the axial coordination between N and the Fe sites forms an optimized axial FeN4+1 structure, disrupting the electron distribution symmetry of Fe and optimizing the electron distribution of the Fe 3d orbital (increasing the d-band center from -1.231 to -0.432eV). Consequently, this led to an enhanced perpendicular adsorption energy of PMS from -1.79 to -1.82eV and reduced energy barriers for the formation of the key reaction intermediate (O*) that generates 1O2. This study provides new insights into PMS activation through the axial coordinated engineering of well-defined SACs in water purification processes.

Multi-omics analysis identifies BCAT2 as a potential pan-cancer biomarker for tumor progression and immune microenvironment modulation.

Branched-chain amino acid transaminase 2 (BCAT2) encodes a crucial protein involved in the initial catalysis of branched-chain amino acid (BCAA) catabolism, with emerging evidence suggesting its association with tumor progression. This study explores BCAT2 in a pan-cancer multi-omics context and evaluates its prognostic significance. We utilized a multi-database approach, analyzing cBioPortal for genetic alterations, RNA-Seq data from TCGA and GTEx for expression patterns, and RSEM for transcript analysis. Protein expression and interaction networks were assessed using the Human Protein Atlas, UniProt, and STRING. Prognostic value was determined through Cox regression analysis of TCGA clinical survival data, while immune cell infiltration across various cancers was examined using TCGA data and the TIMER2 platform. Our results revealed that BCAT2 alterations are primarily amplifications and is upregulated in various tumors, correlating with poor survival rates in several tumor types, including GBMLGG, LGG, and UVM. Elevated BCAT2 protein levels were common in pan-cancer, interacting with a range of metabolic enzymes. Additionally, BCAT2 expression significantly influenced CD4+ T cells, CD8+ T cells, and Treg cells infiltration, with varied correlations across cancer types. These findings indicate BCAT2 as a potential biomarker for cancer diagnosis and therapy, potentially regulating key metabolic and immune factors to mediate tumor progression and the microenvironment.

Injectable Magnetic Hydrogel Incorporated with Anti-Inflammatory Peptide for Efficient Magnetothermal Treatment of Endometriosis.

Endometriosis is a prevalent gynecological condition characterized by chronic pelvic pain, dysmenorrhea, and infertility, affecting ≈176 million women of reproductive age worldwide. Current treatments, including pharmacological and surgical interventions, are often associated with significant side effects and high recurrence rates. Consequently, there is an urgent need for innovative and safer therapeutic approaches. In this study, an injectable magnetic hydrogel nanosystem is developed designed for the dual-purpose magnetothermal and anti-inflammatory treatment of endometriosis. This hydrogel incorporates Fe3O4 nanoparticles alongside an anti-inflammatory peptide. Upon magnetic activation, the Fe3O4 nanoparticles induce a localized hyperthermic response, raising the temperature of endometriotic lesions to 63.3°C, effectively destroying endometriotic cells. Concurrently, the thermally responsive hydrogel facilitates the controlled release of the anti-inflammatory peptide, thus modulating the inflammatory milieu. The biocompatibility and complete in vivo degradability of the hydrogel further enhance its therapeutic potential. The in vivo studies demonstrated that this injectable magnetic hydrogel system achieved a 90% reduction in the volume of endometriotic lesions and significantly decreased inflammatory markers, offering a promising non-invasive treatment modality for endometriosis. By integrating precise lesion ablation with the modulation of the inflammatory microenvironment, this system represents a novel approach to the clinical management of endometriosis.

Polymeric nanocarrier via metabolism regulation mediates immunogenic cell death with spatiotemporal orchestration for cancer immunotherapy

The limited efficacy of cancer immunotherapy occurs due to the lack of spatiotemporal orchestration of adaptive immune response stimulation and immunosuppressive tumor microenvironment modulation. Herein, we report a nanoplatform fabricated using a pH-sensitive triblock copolymer synthesized by reversible addition-fragmentation chain transfer polymerization enabling in situ tumor vaccination and tumor-associated macrophages (TAMs) polarization. The nanocarrier itself can induce melanoma immunogenic cell death (ICD) via tertiary amines and thioethers concentrating on mitochondria to regulate metabolism in triggering endoplasmic reticulum stress and upregulating gasdermin D for pyroptosis as well as some features of ferroptosis and apoptosis. After the addition of ligand cyclic arginine-glycine-aspartic acid (cRGD) and mannose, the mixed nanocarrier with immune adjuvant resiquimod encapsulation can target B16F10 cells for in situ tumor vaccination and TAMs for M1 phenotype polarization. In vivo studies indicate that the mixed targeting nanoplatform elicits tumor ICD, dendritic cell maturation, TAM polarization, and cytotoxic T lymphocyte infiltration and inhibits melanoma volume growth. In combination with immune checkpoint blockade, the survival time of mice is markedly prolonged. This study provides a strategy for utilizing immunoactive materials in the innate and adaptive immune responses to augment cancer therapy.

Identification of SLC22A17 DNA methylation hotspot as a potential biomarker in cutaneous melanoma

BackgroundCancer onset and progression are driven by genetic and epigenetic alterations leading to oncogene activation and the silencing of tumor suppressor genes. Among epigenetic mechanisms, DNA methylation (methDNA) is gaining growing interest in cancer. Promoter hypomethylation is associated with oncogene activation while intragenic methDNA can be involved in transcriptional elongation, alternative spicing, and the activation of cryptic start sites. Several genes involved in the modulation of the tumor microenvironment are regulated by methDNA, including the Solute Carrier Family 22 Member 17 (SLC22A17), which is involved in iron trafficking and extracellular matrix remodeling cooperating with the Gelatinase-Associated Lipocalin (NGAL) ligand. However, the exact role of intragenic methDNA in cancer has not been fully investigated. Therefore, the aim of the present study is to explore the role of methDNA in the regulation of SLC22A17 in cutaneous melanoma (CM), used as a tumor model.MethodsCorrelation and differential analyses between SLC22A17 expression and methDNA were performed using the data contained in The Cancer Genome Atlas and Gene Expression Omnibus databases. Functional studies on melanoma cell lines treated with 5-Azacytidine (5-Aza) were conducted to assess the correlation between methDNA and SLC22A17 expression. A validation study on the diagnostic potential of the in silico-identified SLC22A17 methDNA hotspot was finally performed by analyzing tissue samples obtained from CM patients and healthy controls.ResultsThe computational analyses revealed that SLC22A17 was significantly downregulated in CM, and its expression was related to promoter hypomethylation and intragenic hypermethylation. Moreover, SLC22A17 overexpression and hypermethylation of two intragenic methDNA hotspots were associated with a better clinical outcome in CM patients. The correlation between SLC22A17 methDNA and expression was confirmed in 5-Aza-treated cells. In agreement with in silico analyses, the SLC22A17 promoter methylation hotspot showed higher methDNA levels in CM samples compared to nevi. In addition, the methDNA levels of this hotspot were positively correlated with advanced CM.ConclusionsThe SLC22A17 methDNA hotspot could represent a promising biomarker for CM, highlighting the regulatory role of methDNA on SLC22A17 expression. These results pave the way for the identification of novel epigenetic biomarkers and therapeutic targets for the management of CM patients.

CXCL12+ Tumor-associated Endothelial Cells Promote Immune Resistance in Hepatocellular Carcinoma.

BackgroundThe tumor microenvironment (TME) plays a crucial role in the limited efficacy of existing treatments for hepatocellular carcinoma (HCC), with tumor-associated endothelial cells (TECs) serving as fundamental TME components that substantially influence tumor progression and treatment efficacy. However, the precise roles and mechanisms of TECs in HCC remain inadequately understood. MethodsWe employed a multi-omics profiling strategy to investigate the single-cell and spatiotemporal evolution of TECs within the microenvironment of HCC tumors showcasing varied responses to immunotherapy. Through an analysis of a clinical cohort of HCC patients, we explored the correlation between TEC subpopulations and immunotherapy outcomes. The influence of TEC subsets on the immune microenvironment was confirmed through comprehensive in vitro and in vivo studies. To further explore the mechanisms of distinct TEC subpopulations in microenvironmental modulation and their impact on immunotherapy, we utilized TEC subset-specific knockout mouse models as well as humanized mouse models. ResultsIn this research, we identified a new subset of CXCL12+ TECs that exert a crucial role in immune suppression within the HCC TME. Functionally, CXCL12+ TECs impede the differentiation of CD8+ naïve T cells into CD8+ cytotoxic T cells by secreting CXCL12. Furthermore, they attract myeloid-derived suppressor cells (MDSCs). A bispecific antibody was developed to target both CXCL12 and PD1 specifically, showing significant promise in bolstering anti-tumor immune responses and advancing HCC therapy. ConclusionsCXCL12+ TECs are pivotal in mediating immunosuppression within HCC microenvironment and targeting CXCL12+ TECs presents a promising approach to augment the efficacy of immunotherapies in HCC patients. Impact and implicationThis investigation reveals a pivotal mechanism in the HCC TME, where CXCL12+ TECs emerge as crucial modulators of immune suppression. The discovery of CXCL12+ TECs as inhibitors of CD8+ naïve T cell activation and recruiters of MDSCs significantly advances our grasp of the dynamic between HCC and immune regulation. Moreover, the development and application of a bispecific antibody precisely targeting CXCL12 and PD1 has proven to enhance immune responses in a humanized mouse HCC model. This finding underscores a promising therapeutic direction for HCC, offering the potential to amplify the impact of current immunotherapies.

Dual cross-linked polyurethane-alginate biomimetic hydrogel for elastic gradient simulation in osteochondral structures: Microenvironment modulation and tissue regeneration

The distinctive composition and functions of osteochondral structures result in constrained regeneration. Insufficient healing processes may precipitate the emergence of tissue growth disorders or excessive subchondral bone formation, which can culminate in the deterioration and failure of osteochondral tissue repair. To overcome these limitations, materials designed for osteochondral repair must provide region-specific modulation of the microenvironment and mechanical compatibility. To address these challenges, we propose a method to create continuous hydrogels with distinct structural and functional properties by a precise cross-linking method. We have developed an innovative polyurethane enriched with dimethylglyoxime, facilitating the coordinated loading and precise release of Zn2+. This strategy enables the meticulous control of alginate cross-linking, resulting in an elastic gradient hydrogel that closely resembles the osteochondral interface. The SeSe within the hydrogel effectively modulates the inflammatory microenvironment and fosters the M2 polarization of macrophages. The hydrogel's lower layer is designed to rapidly release Zn2+, thereby enhancing bone regeneration. The upper layer is intended to prevent bone overgrowth and stimulate chondrogenic differentiation. This dual-layer strategy allows targeted stimuli to each region, promoting the seamless integration of neoosteochondral tissue. Our study demonstrates the potential of this stratified hydrogel in achieving uniform and smooth osteochondral tissue regeneration.

Synergistic modulation of interfacial and coordination microenvironment for highly efficient uranium extraction

Extracting uranium from wastewater is highly essential for addressing environmental pollution and sustainable development of nuclear power. However, the design and synthesis of functional adsorbents for selective and rapid uranium adsorption remains extremely challenging. Herein, we report the synthesis of a functionalized hyper-cross-linked polymers (PHCP-Q) via an interfacial and coordination microenvironment synergistic modulation strategy for efficient uranium adsorption. The generated interfacial hydrophilic microenvironment allows the rapid migration of uranyl from the solution to the adsorbent and thus enables fast adsorption kinetics. Meanwhile, the fine-tuned coordination microenvironment within pore space creates the hexa-coordinated nano-pocket structure and thereby enhances the selective recognition of uranyl. Remarkably, PHCP-Q achieves adsorption equilibrium within simply 60 min and shows high saturation U(VI) adsorption uptake of 608.95 mg/g. More importantly, PHCP-Q with the cooperation of binding sites exhibits the highest distribution coefficient by an order of magnitude compared with that of other PHCPs. Besides, PHCP-Q possesses good physicochemical stability and recyclability. This study provides a new insight into the future design of highly effective uranium adsorbents by synergistically modulating interfacial and coordination microenvironment, which can be extended to the extraction of other target ions.

Exploring the Mechanisms and Current Status of Acupuncture in Alleviating Tumor Metabolism and Associated Diseases: Insights from the Central Nervous System and Immune Microenvironment

Acupuncture, as a traditional Chinese medical treatment, has garnered increasing attention in recent years in fields such as tumor metabolism, the central nervous system, and the immune microenvironment. This paper aims to explore the fundamental principles, mechanisms, and research status of acupuncture therapy for tumor-related diseases. Firstly, we introduce the basic principles of acupuncture therapy, including the theories of meridians and its theoretical basis in tumor treatment. Secondly, we systematically review the mechanisms of acupuncture therapy for tumor-related diseases, discussing how acupuncture alleviates side effects such as pain, depression, fatigue, and gastrointestinal discomfort caused by conventional treatments through modulation of the immune microenvironment, central nervous system, and endocrine system. Subsequently, we discuss the current research status of acupuncture therapy for tumor-related diseases, as well as the application of current research methods and technologies in elucidating acupuncture mechanisms. Additionally, by combining clinical practice with different types of tumor-related diseases as experimental subjects, we demonstrate the application effectiveness and clinical practice experience of acupuncture in tumor treatment. Finally, a comprehensive assessment of acupuncture therapy for tumor-related diseases is provided, summarizing its limitations and prospecting future directions, including interdisciplinary collaboration and personalized treatment. In conclusion, acupuncture, as a feasible adjunctive therapy, is closely related to the central nervous system and the immune microenvironment, holding potential significant value in tumor treatment.

Microenvironment modulation of biocatalyst derived from natural cellulose of wheat straw for enhancing p-nitrophenol degradation via boosting peroxymonosulfate activation

Defect-rich nitrogen-doped biocatalyst (B-NC) was synthesized from natural cellulose of wheat straw using straightforward mechanical method and one-step pyrolysis approach. In contrast to the nitrogen-doped biocatalyst (NC), by leveraging the synergistic effects of nitrogen dopants and surface defects, the microenvironment-modulated B-NC exhibited the enhanced mass transfer efficiency and a significant improvement in reactivity for p-nitrophenol degradation (111 %–196 %). The catalyst's exceptional performance primarily arose from graphitic N, pyridinic N and CO active sites, which mainly derived from the cellulose structure of wheat straw and nitrogen dopants. Electron paramagnetic resonance and quenching tests confirmed that the B-NC/peroxymonosulfate system generated more reactive species (SO4•−, •OH, O2•−, and 1O2) during p-nitrophenol degradation, surpassing the NC/peroxymonosulfate system. Additionally, both density functional theory calculations and electrochemical experiments provided evidence of peroxymonosulfate strongly adsorbing onto B-NC's defect sites, facilitating the formation of catalyst/peroxymonosulfate* complexes and promoting electron transfer processes. This research provides valuable insights into the regulation of defects in nitrogen-doped biocatalyst derived from natural cellulose, presenting a promising solution for remediating refractory organic pollutants.

The Therapeutic Potential of Targeting Tumor Microenvironment and Modulation of Immunotherapy in Gastrointestinal Cancer.

Immunotherapy, as a novel treatment approach for various disorders, including cancers, is designed to either stimulate or suppress the immune system with high speci-ficity. The recent achievements of this therapy in clinical trials are set to transform tradi-tional treatment methods. Furthermore, it holds promise for enhancing the survival rates of patients suffering from both metastatic cancers and primary stages. Gastrointestinal Cancers (GI) account for 26% of global incidence and 35% of worldwide deaths. Treat-ment can be carried out using targeted immunotherapy in these cancers. If the tiers are superior, improvement could require more enterprise. On account that the function of immunotherapy in GI has been so promising, solely in sufferers with severe metastatic levels, within the literature, the immune checkpoint inhibitors in cancer immunotherapy of GI cancers, chimeric antigen receptor T-cell (vehicle-T), modulators of the tumor mi-croenvironment, and drug resistance mechanisms in immunotherapy as an effective treatment approach to GI cancers along with colon, pancreas, gastric, and esophageal cancers have been addressed. This review provides an overview of FDA-approved im-munotherapy drugs and ongoing preclinical developments. Additionally, we offer in-sights into the future of immunotherapy for GI cancer patients, addressing the associated challenges.

Magnolol Induces Apoptosis and Suppresses Immune Evasion in Non-small Cell Lung Cancer Xenograft Models.

Non-small cell lung cancer is known for its rapid growth and immune evasion, demanding effective therapies targeting both tumor cells and the microenvironment. Magnolol has shown promising anti-tumor effects in various cancers. CL1-5-F4-bearing mice were divided into control, 40 mg/kg, and 60 mg/kg magnolol groups, once tumors reached 100 mm3 Tumor growth and body weight were monitored biweekly, and after 13 days, mice were euthanized for tumor and organ collection for subsequent staining. Histopathology and serum biochemistry assessed organ toxicity. Magnolol dose-dependently suppressed NSCLC progression, with no pathology alterations observed in normal organs. Magnolol-induced apoptosis and cell cycle arrest, evidenced by increased cleaved caspase-3 and decreased cyclin D1/CDK4 levels. It also down-regulated VEGF, FOXP3, and IDO-1 in tumors, implicating tumor microenvironment modulation. Magnolol exhibits significant antitumor effects in NSCLC by inducing apoptosis, inhibiting proliferation, and modulating the tumor microenvironment. These results support further investigation of magnolol as a therapeutic adjuvant to enhance NSCLC treatment outcomes.

The involvement of aquaporin 5 in the inflammatory response of primary Sjogren's syndrome dry eye: potential therapeutic targets exploration.

Sjogren's syndrome (SS) is a chronic autoimmune disease. Mainly due to the infiltration of lymphoplasmic cells into the exocrine glands, especially the salivary glands and lacrimal glands, resulting in reduced tear and saliva secretion. Reduced tear flow can trigger Sjogren's syndrome dry eye (SSDE). Although the pathophysiology of SSDE xerosis remains incompletely understood, recent advances have identified aquaporin-5 (AQP5) as a critical factor in dysregulation of the exocrine gland and epithelium, influencing the clinical presentation of SSDE through modulation of inflammatory microenvironment and tear secretion processes. This review aims to explore AQP5 regulatory mechanisms in SSDE and analyze its potential as a therapeutic target, providing new directions for SSDE treatment.

Mechanistic Insight into Anticancer Prowess of Piper Species and their Bioactive Compounds: A Review

Southern Asia boasts a diverse array of Piper species, renowned for their antimicrobial, antioxidant, and anti-inflammatory properties. These plants, also native to the American tropics, have played a significant role in traditional medicine and culinary practices. Notably, Piper longum L., P. nigrum L., and P. betle L. are recognized for their bioactive compounds, particularly alkaloids, which contribute to their beneficial properties. In recent decades, there has been increased focus on studying these plants for their potential anticancer effects, encompassing both direct cytotoxic effects and indirect modulation of the tumor microenvironment. Major scientific literature databases were consulted using appropriate keywords to present a comprehensive and proportionate analysis of the anticancer potential of the three species, including valuable insights into their therapeutic perspectives, molecular mechanisms, and broader applications in cancer treatment. Numerous pharmacological trials on the bioactive components and extracts have underscored their clinical significance, revealing multifaceted actions such as antiproliferative effects, antiangiogenic properties, immunomodulation, antimetastatic activity, induction of apoptosis, and modulation of various signaling pathways in both malignant and non-malignant disorders. Among the explored compounds, piperine and piperlongumine, prominent alkaloids within the Piper genus, have demonstrated notable efficacy in restricting the growth of cancer cells and tumors. This article emphasizes the biomedical and pharmacological findings related to the anticancer properties of the three Piper species, with a focus on their mechanism of action. These insights could open avenues for future clinical scenarios and therapeutic utilization of bioactive substances and extracts derived from these species.

Emerging insights into thyroid cancer from immunotherapy perspective: A bibliometric analysis

ABSTRACT Thyroid cancer is a common endocrine malignancy that poses considerable therapeutic challenges in treating anaplastic carcinoma and advanced aggressive disease. Immunotherapy has become a prominent strategy for cancer treatment, and has shown remarkable advancements in recent years. In this study, we utilized visualization and bibliometric tools to analyze publications on thyroid cancer immunotherapy from the Web of Science Core Collection (WoSCC). A total of 409 articles were included, with an annual increase in both publications and citations since 2016. China leads research efforts in this area, while the University of Texas System and UTMD Anderson Cancer Center rank first in publication output. The journal Thyroid has garnered the highest citations. Notable authors contributing to this field include Antonelli Alessandro, Fallahi Poupak, and Wang Yu. Current research hotspots include immune checkpoint inhibitors, combination therapies involving immunotherapy with targeted therapy, CAR-T cell therapy, and modulation of the tumor microenvironment, all of which underscore the evolving landscape and potential for innovative treatments in thyroid cancer.

From pathogenesis to treatment: the impact of bacteria on cancer.

The intricate relationship between cancer and bacteria has garnered increasing attention in recent years. While traditional cancer research has primarily focused on tumor cells and genetic mutations, emerging evidence highlights the significant role of microbial communities within the tumor microenvironment in cancer development and progression. This review aims to provide a comprehensive overview of the current understanding of the complex interplay between cancer and bacteria. We explore the diverse ways in which bacteria influence tumorigenesis and tumor behavior, discussing direct interactions between bacteria and tumor cells, their impact on tumor immunity, and the potential modulation of the tumor microenvironment. Additionally, we delve into the mechanisms through which bacterial metabolites and extracellular products May affect cancer pathways. By conducting a thorough analysis of the existing literature, we underscore the multifaceted and intricate relationship between bacteria and cancer. Understanding this complex interplay could pave the way for novel therapeutic approaches and preventive strategies in cancer treatment.

Abstract A048: Paricalcitol improves survival in tumor-permissive cancer-associated fibroblast subtype of pancreatic cancers

Abstract INTRODUCTION: Pancreatic ductal adenocarcinoma (PDAC) remains a deadly disease with poor survival and limited therapy options. While traditional cytotoxic agents target cancer cells, there has been growing interest in tumor microenvironment (TME) modulation given that desmoplastic stroma and immune suppression are hallmarks of PDAC. Recently, vitamin D agonism has been identified as a potential treatment to normalize the PDAC TME. We have previously described tumor-intrinsic and cancer-associated fibroblast (CAF) subtypes of PDAC that independently predict survival, but whether these subtypes are associated with outcomes after TME modulation has not been studied. METHODS: We evaluated the association of treatment outcomes in a Phase 2 trial of neoadjuvant nab-paclitaxel (A), gemcitabine (G), cisplatin (C), and paricalcitol (P) (NCT03138720) and a Phase 2 trial of A+G+C+hydroxychloroquine (HCQ) (NCT04669197) in patients with non-metastatic PDAC. RNA-sequencing was performed on 28 pretreatment biopsy samples. PurIST and DeCAF were used to determine tumor-intrinsic and CAF subtypes, respectively. Clinical variables such as CA19-9 levels, resectability, and overall survival (OS) were examined. RESULTS: For tumor-intrinsic subtypes, 5 tumors (18%) were basal-like and 23 (82%) were classical. For CAF subtypes, 11 (39%) were tumor-permissive (perm)CAF and 17 (61%) were tumor-restraining (rest)CAF. Neither tumor-intrinsic or CAF subtypes were associated with CA19-9 normalization or resectability at time of diagnosis in either trial. OS was available for NCT03138720; patients with basal-like tumors receiving A+G+C+P had worse median survival of 12.3 months compared to 20.9 months for those with classical tumors, although this difference did not reach statistical significance (log-rank P = 0.065). In two independent cohorts of 925 and 129 patients, those with permCAF tumors had an increased hazard ratio of at least 1.5 (P < 0.001) compared to patients with restCAF tumors for OS. Compared to this historical data, we did not find a difference in OS between patients with permCAF tumors (19.5 months) compared to restCAF tumors (19.7 months, log-rank P = 0.56). CONCLUSION: In the study of A+G+C+P, there was a disparity in OS between patients with basal-like vs. classical tumors, in contrast to the interim results of the COMPASS and PASS-01 trials, where patients with basal-like tumors receiving A+G had similar OS compared to patients with classical tumors. Compared to prior analysis, there was no difference in OS for patients with permCAF tumors vs. those with restCAF tumors, which may suggest that either paricalcitol (or the cytotoxic combination) may be of benefit for patients with permCAF tumors and normalize the CAF landscape. Single-agent studies with paired pre- and post-treatment samples are needed to better understand how to best tailor therapy regiments for patients based on tumor subtypes. Citation Format: Jaewon J Lee, Priscilla S Chan, Changfei Luan, Elena V Kharitonova, Naim U Rashid, Xianlu L Peng, Erkut H Borazanci, Jen Jen Yeh. Paricalcitol improves survival in tumor-permissive cancer-associated fibroblast subtype of pancreatic cancers [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr A048.

Abstract B041: Fibroblast STAT3 Signaling in Pancreatic Cancer: Implications for Immunotherapy and Tumor Microenvironment Modulation

Abstract Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer distinguished by a dense stromal microenvironment. The current investigation delves into the fibroblast-specific STAT3 signaling in the PDAC tumor microenvironment (TME) and its effects on immune cell infiltration and extracellular matrix (ECM) modulation. An association was identified between heightened levels of phosphorylated STAT3 (pSTAT3) in tumor-associated fibroblasts (CAFs) and a more unfavorable prognosis, particularly among male patients. Comparative analysis of gene expression patterns in normal fibroblasts and those deficient in STAT3, extracted from mouse models of pancreatic cancer, unveiled distinct gene expression profiles related to the inflammatory signaling pathway (IL6, ADM, CXCL11, CD80, VEGFA, TGFB1, STC1, STC2). Utilizing ChIP-Seq analysis with an anti-pSTAT3 antibody, it was confirmed that STAT3 binds to the regulatory regions of these genes, supporting its regulatory role in the inflammatory signaling pathway. Moreover, the absence of STAT3 in CAFs resulted in a decline in M2 macrophages and an upsurge in M1 macrophages within the TME, indicating a potential function of STAT3 in influencing macrophage polarization. Noteworthy observations also revealed that STAT3 signaling in CAFs impacts ECM remodeling, as illustrated by reduced collagen deposition. Furthermore, the deficiency of STAT3 in CAFs led to a notable reduction in the quantity of neutrophils within the TME in our mouse model. Additionally, a plausible involvement of STAT3 in neutrophil recruitment and activation through the CXCL1/CXCR2 axis was indicated. Alterations in the infiltration of neutrophils and macrophages due to the absence of STAT3 could profoundly influence the immune response against PDAC. The modified composition of ECM following STAT3 deletion might also impact the infiltration and functioning of immune cells. These outcomes underscore the significance of STAT3 signaling in CAFs as a promising therapeutic target in PDAC, offering potential for modulating the tumor microenvironment, augmenting anti-tumor immunity, and advancing patient outcomes. Citation Format: Samaneh Saberi, Cameron Bumbleburg, Caroline Everett, Julia E Lefler, Victoria Jordan, Lu Han, Sudarshana Sharma, Michael C. Ostrowski. Fibroblast STAT3 Signaling in Pancreatic Cancer: Implications for Immunotherapy and Tumor Microenvironment Modulation [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr B041.

Microenvironment modulation of Fe-porphyrinic metal–organic frameworks for CO2 photoreduction

Photocatalytic CO2 reduction to fuels and chemicals is a promising pathway towards carbon resource recovery. Herein, three isomorphic Fe-porphyrinic MOFs, Zr6O4(OH)4(Fe-TCPP)3 (MOF-525, Fe-TCPP = iron 5,10,15,20-tetra(4-carboxyphenyl)-porphyrin), Zr6O4(OH)4(Fe-TCPP-NO2)3 (MOF-525-NO2, Fe-TCPP-NO2 = iron 5,10,15,20-tetra(2-nitro-4-carboxyphenyl)-porphyrin), and Zr6O4(OH)4(Fe-TCBPP-NO2)3 (MOF-526-NO2, Fe-TCBPP-NO2 = iron 5,10,15,20-tetra[4-(4′-carboxyphenyl)-2-nitrophenyl]-porphyrin) were synthesized and employed as photocatalysts for CO2 reduction. Among them, MOF-525-NO2 exhibited the highest catalytic activity with CO and H2 yields of 10.36 and 0.46 mmol·g−1 without any photosensitizer under visible light. Mechanism investigations suggested that the micro-environments of these MOFs were adjusted by introducing porphyrinic fragments with different lengths and functional groups, resulting in stronger CO2 affinity, faster photocurrent response, and efficient photogenerated electron-hole separation and transfer, which finally promoted the efficiency for photocatalytic CO2 reduction.