Signal Transducer And Activator Of Transcription 3 Research Articles

Exploring the mechanism of dendrobine in treating metabolic associated fatty liver disease based on network pharmacology and experimental validation

BackgroundThis study investigates the therapeutic mechanisms of dendrobine, a primary bioactive compound in Dendrobium nobile, for Metabolic Associated Fatty Liver Disease (MASLD) management. Utilizing network pharmacology combined with experimental validation, the clinical effectiveness of dendrobine in MASLD treatment was assessed and analyzed.ResultsThe study demonstrates significant improvement in liver function among MASLD patients treated with Dendrobium nobile. Network pharmacology identified key targets such as Peroxisome Proliferator-Activated Receptor Gamma (PPARG), Interleukin 6 (IL6), Tumor Necrosis Factor (TNF), Interleukin 1 Beta (IL1B), and AKT Serine/Threonine Kinase 1 (AKT1), with molecular docking confirming their interactions. Additionally, dendrobine significantly reduced ALT and AST levels in palmitic acid-treated HepG2 cells, indicating hepatoprotective properties and amelioration of oxidative stress through decreased Malondialdehyde (MDA) levels and increased Superoxide Dismutase (SOD) levels.ConclusionDendrobine mitigates liver damage in MASLD through modulating inflammatory and immune responses and affecting lipid metabolism, potentially by downregulating inflammatory mediators like TNF, IL6, IL1B, and inhibiting AKT1 and Signal Transducer and Activator of Transcription 3 (STAT3). This study provides a theoretical basis for the application of dendrobine in MASLD treatment, highlighting its potential as a therapeutic agent.

Anti-carcinogenic Potential of Nano-curcumin -“Killing Cancerous Cells”

Abstract:: Nowadays, cancer treatment is currently limited to surgery, chemotherapy, and radiation, which carry the risk of damaging the normal tissue of the body and incomplete removal of the cancerous cells from the body. Thus, the Nano technique offers a great means to target therapies directly on cancerous cells and neoplasm. Moreover, because nano-based formulations of polyphenolic curcumin show a major effect on cancer and tumour cells, nanoparticles have a tendency to overcome the hydrophobic nature of curcumin to improve its stability and bioavailability in vitro and in vivo. It is apparent from the studies that Curcumin has shown anticancer effects by regulating various immunomodulators, which include cytokines, reactive oxygen species, and cyclooxygenase-2 (COX-2). It also takes part in the downregulation of growth factors, protein kinases, oncogenic molecules, and various signalling pathways, such as nuclear factor kappalight- chain enhancer of activated B cells (NF-κB), c-Jun N-terminal kinase (JNK), and signal transducer and activator of transcription 3 (STAT3) signalling. According to recent studies and clinical trials, nano curcumin shows a major effect on cancerous cells. In this article, the authors summarised the mechanism of nano curcumin in various metastatic cancers and the most recent clinical trials performed.

Tumor-associated NK cells drive MDSC-mediated tumor immune tolerance through the IL-6/STAT3 axis.

Apart from their killer identity, natural killer (NK) cells have integral roles in shaping the tumor microenvironment. Through immune gene deconvolution, the present study revealed an interplay between NK cells and myeloid-derived suppressor cells (MDSCs) in nonresponders of immune checkpoint therapy. Given that the mechanisms governing the outcome of NK cell-to-myeloid cell interactions remain largely unknown, we sought to investigate the cross-talk between NK cells and suppressive myeloid cells. Upon contact with tumor-experienced NK cells, monocytes and neutrophils displayed increased expression of MDSC-related suppressive factors along with increased capacities to suppress T cells. These changes were accompanied by impaired antigen presentation by monocytes and increased ER stress response by neutrophils. In a cohort of patients with sarcoma and breast cancer, the production of interleukin-6 (IL-6) by tumor-infiltrating NK cells correlated with S100A8/9 and arginase-1 expression by MDSCs. At the same time, NK cell-derived IL-6 was associated with tumors with higher major histocompatibility complex class I expression, which we further validated with b2m-knockout (KO) tumor mice models. Similarly in syngeneic wild-type and IL-6 KO mouse models, we then demonstrated that the accumulation of MDSCs was influenced by the presence of such regulatory NK cells. Inhibition of the IL-6/signal transducer and activator of transcription 3 (STAT3) axis alleviated suppression of T cell responses, resulting in reduced tumor growth and metastatic dissemination. Together, these results characterize a critical NK cell-mediated mechanism that drives the development of MDSCs during tumor immune escape.

A Carbon 21 Steroidal Glycoside with Pregnane Skeleton from Cynanchum atratum Bunge Promotes Megakaryocytic and Erythroid Differentiation in Erythroleukemia HEL Cells through Regulating Platelet-Derived Growth Factor Receptor Beta and JAK2/STAT3 Pathway.

Erythroleukemia is a rare form of acute myeloid leukemia (AML). Its molecular pathogenesis remains vague, and this disease has no specific therapeutic treatments. Previously, our group isolated a series of Carbon 21 (C-21) steroidal glycosides with pregnane skeleton from the root of Cynanchum atratum Bunge. Among them, we found that a compound, named BW18, can induce S-phase cell cycle arrest and apoptosis via the mitogen-activated protein kinase (MAPK) pathway in human chronic myeloid leukemia K562 cells. However, its anti-tumor activity against erythroleukemia remains largely unknown. In this study, we aimed to investigate the anti-erythroleukemia activity of BW18 and the underlying molecular mechanisms. Our results demonstrated that BW18 exhibited a good anti-erythroleukemia activity in the human erythroleukemia cell line HEL and an in vivo xenograft mouse model. In addition, BW18 induced cell cycle arrest at the G2/M phase and promoted megakaryocytic and erythroid differentiation in HEL cells. Furthermore, RNA sequencing (RNA-seq) and rescue assay demonstrated that overexpression of platelet-derived growth factor receptor beta (PDGFRB) reversed BW18-induced megakaryocytic differentiation in HEL cells, but not erythroid differentiation. In addition, the network pharmacology analysis, the molecular docking and cellular thermal shift assay (CETSA) revealed that BW18 could inactivate Janus tyrosine kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway, which might mediate BW18-induced erythroid differentiation. Taken together, our findings elucidated a novel role of PDGFRB in regulating erythroleukemia differentiation and highlighted BW18 as an attractive lead compound for erythroleukemia treatment.

Leptin Promotes Vasculogenic Mimicry in Breast Cancer Cells by Regulating Aquaporin-1.

Leptin is an obesity-related hormone that plays an important role in breast cancer progression. Vasculogenic mimicry (VM) refers to the formation of vascular channels lined by tumor cells. This study aimed to investigate the relationship between leptin and VM in human breast cancer cells. VM was measured by a 3D culture assay. Signal transducers and activators of transcription 3 (STAT3) signaling, aquaporin-1 (AQP1), and the expression of VM-related proteins, including vascular endothelial cadherin (VE-cadherin), twist, matrix metalloproteinase-2 (MMP-2), and laminin subunit 5 gamma-2 (LAMC2), were examined by Western blot. AQP1 mRNA was analyzed by a reverse transcriptase-polymerase chain reaction (RT-PCR). Leptin increased VM and upregulated phospho-STAT3, VE-cadherin, twist, MMP-2, and LAMC2. These effects were inhibited by the leptin receptor-blocking peptide, Ob-R BP, and the STAT3 inhibitor, AG490. A positive correlation between leptin and AQP1 mRNA was observed and was confirmed by RT-PCR. Leptin upregulated AQP1 expression, which was blocked by Ob-R BP and AG490. AQP1 overexpression increased VM and the expression of VM-related proteins. AQP1 silencing inhibited leptin-induced VM and the expression of VM-related proteins. Thus, these results showed that leptin facilitates VM in breast cancer cells via the Ob-R/STAT3 pathway and that AQP1 is a key mediator in leptin-induced VM.

Salidroside promotes the repair of spinal cord injury by inhibiting astrocyte polarization, promoting neural stem cell proliferation and neuronal differentiation

Spinal cord injury (SCI) remains a formidable challenge, lacking effective treatments. Following SCI, neural stem cells (NSCs) migrate to SCI sites, offering a potential avenue for nerve regeneration, but the effectiveness of this intrinsic repair mechanism remains suboptimal. Salidroside has demonstrated pro-repair attributes in various pathological conditions, including arthritis and cerebral ischemia, and the ability to curtail early-stage inflammation following SCI. However, the specific role of salidroside in the late-stage repair processes of SCI remains less defined. In this investigation, we observed that continuous salidroside treatment in SCI mice improved motor function recovery. Immunofluorescence-staining corroborated salidroside’s capacity to stimulate nerve regeneration and remyelination, suppress glial scar hyperplasia, reduce the activation of neurotoxic A1 astrocytes, and facilitate NSCs migration towards the injured region. Mechanistically, in vitro experiments elucidated salidroside’s significant role in restraining astrocyte proliferation and A1 polarization. It was further established that A1 astrocytes hinder NSCs proliferation while inducing their differentiation into astrocytes. Salidroside effectively ameliorated this inhibition of NSCs proliferation through diminishing c-Jun N-terminal kinase (JNK) pathway phosphorylation and restored their differentiation into neurons by suppressing the signal transducer and activator of transcription 3 (STAT3) pathway. In summary, our findings suggest that salidroside holds promise as a therapeutic agent for traumatic SCI treatment.

Vesicle-associated membrane protein 8 knockdown exerts anti-proliferative, pro-apoptotic, anti-autophagic, and pro-ferroptotic effects on colorectal cancer cells by inhibition of the JAK/STAT3 pathway.

Vesicle-associated membrane protein 8 (VAMP8), a soluble n-ethylmaleimide-sensitive factor receptor protein, acts as an oncogenic gene in the progression of several malignancies. Nevertheless, the roles and mechanisms of VAMP8 in colorectal cancer (CRC) progression remain unknown. The expression and prognostic significance of VAMP8 in CRC samples were analyzed through bioinformatics analyses. Cell proliferation was detected using CCK-8 and EdU incorporation assays and apoptosis was evaluated via flow cytometry. Western blot analysis was conducted to examine the protein expression. Ferroptosis was evaluated by measurement of iron metabolism, lipid peroxidation, and glutathione (GSH) content. VAMP8 was increased in CRC samples relative to normal samples on the basis of GEPIA and HPA databases. CRC patients with high level of VAMP8 had a worse overall survival. VAMP8 depletion led to a suppression of proliferation and promotion of apoptosis in CRC cells. Additionally, VAMP8 knockdown suppressed beclin1 expression and LC3-II/LC3-I ratio, elevated p62 expression, increased Fe2+, labile iron pool, lipid reactive oxygen species, and malondialdehyde levels, and repressed GSH content and glutathione peroxidase activity. Moreover, VAMP8 knockdown inhibited the activation of janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathway in CRC cells. Mechanistically, activation of the JAK/STAT3 pathway by JAK1 or JAK2 overexpression attenuated VAMP8 silencing-mediated anti-proliferative, pro-apoptotic, anti-autophagic, and pro-ferroptotic effects on CRC cells. In conclusion, VAMP8 knockdown affects the proliferation, apoptosis, autophagy, and ferroptosis by the JAK/STAT3 pathway in CRC cells.

Leptin combined with withaferin A boost posthemorrhagic neurogenesis via activation of STAT3/SOCS3 pathway

Neurogenesis as a potential strategy to improve the consequences of intracerebral hemorrhage (ICH). The current study investigates the effects of withaferin A (WFA) in combination with leptin (LEP) on ICH and neurogenesis mechanisms. LEP levels were dramatically reduced on days 7 and 14 following ICH insults in mice, but continuous WFA therapy significantly improved the potency of intrinsic LEP on day 14 after ICH. Furthermore, WFA combined with LEP enhances intrinsic neurogenesis and lessen motor deficits and long-term cognitive outcomes after ICH. In parallel, leptin deficiency in ob/ob mice limits enhancement of neurogenesis following ICH in response to WFA combined with LEP treatment. Importantly, the functional recovery conferred by WFA combined with LEP after ICH was inhibited by neurogenesis suppression. Mechanistically, this study unveiled that the signal transducer and activator of transcription-3 (STAT3) / suppressor of cytokine signaling-3 (SOCS3) pathway is a critical signaling pathway through which WFA combined with LEP treatment promotes intrinsic neurogenesis after ICH. Collectively, the results of this study elucidate the neuroprotective effects of WFA and LEP in ICH, and highlight a potential approach for ICH cell therapy.

Exploring the mechanism of Jinlida granules against type 2 diabetes mellitus by an integrative pharmacology strategy

Jinlida granule (JLD) is a Traditional Chinese Medicine (TCM) formula used for the treatment of type 2 diabetes mellitus (T2DM). However, the mechanism of JLD treatment for T2DM is not fully revealed. In this study, we explored the mechanism of JLD against T2DM by an integrative pharmacology strategy. Active components and corresponding targets were retrieved from Traditional Chinese Medicine System Pharmacology (TCMSP), SwissADME and Bioinformatics Analysis Tool for Molecular Mechanisms of Traditional Chinese Medicine Database (BATMAN-TCM) database. T2DM-related targets were obtained from Drugbank and Genecards databases. The protein–protein interaction (PPI) network was constructed and analyzed with STRING (Search Toll for the Retrieval of Interacting Genes/proteins) and Cytoscape to get the key targets. Then, Gene Ontology (GO) and Kyoto Encyclopedia of Gene and Genomes (KEGG) enrichment analyses were performed with the Database for Annotation, Visualization and Integrated Discovery (DAVID). Lastly, the binding capacities and reliability between potential active components and the targets were verified with molecular docking and molecular dynamics simulation. In total, 185 active components and 337 targets of JLD were obtained. 317 targets overlapped with T2DM-related targets. RAC-alpha serine/threonine-protein kinase (AKT1), tumor necrosis factor (TNF), interleukin-6 (IL-6), cellular tumor antigen p53 (TP53), prostaglandin G/H synthase 2 (PTGS2), Caspase-3 (CASP3) and signal transducer and activator of transcription 3 (STAT3) were identified as seven key targets by the topological analysis of the PPI network. GO and KEGG enrichment analyses showed that the effects were primarily associated with gene expression, signal transduction, apoptosis and inflammation. The pathways were mainly enriched in PI3K-AKT signaling pathway and AGE-RAGE signaling pathway in diabetic complications. Molecular docking and molecular dynamics simulation verified the good binding affinity between the key components and targets. The predicted results may provide a theoretical basis for drug screening of JLD and a new insight for the therapeutic effect of JLD on T2DM.

Spinal lipocalin 2 as a factor in the development of central post-stroke pain

Central poststroke pain (CPSP) is a type of central neuropathic pain whose mechanisms remain unknown. Recently, we showed that activated astrocytes and microglial cells are present in the spinal cord of CPSP model mice. Activated glial cells exacerbate cerebral ischemic pathology by increasing the expression of inflammatory factors. However, the involvement of spinal glial cells in CPSP remains unknown. We hypothesized that spinal glial cell-derived molecules cause hyperexcitability or promoted the development of CPSP. In this study, we identified glial cell-derived factors involved in the development of CPSP using a bilateral common carotid occlusion (BCAO)-induced CPSP mouse model. Male ddY mice were subjected to BCAO for 30 min. The von Frey test assessed mechanical hypersensitivity in the right hind paw of mice. BCAO mice showed hypersensitivity to mechanical stimuli and astrocyte activation in the spinal cord 3 days after treatment. DNA microarray analysis revealed a significant increase in lipocalin 2 (LCN2), is known as neutrophil gelatinase-associated lipocalin, in the superficial dorsal horns of BCAO-induced CPSP model mice. LCN2 colocalized with GFAP, an astrocyte marker. Spinal GFAP-positive cells in BCAO mice co-expressed signal transducer and activator of transcription 3 (STAT3). The increase in the fluorescence intensity of LCN2 and GFAP in BCAO mice was suppressed by intrathecal injection of AG490, an inhibitor of JAK2 and downstream STAT3 activation, or anti-LCN2 antibody. Our findings indicated that LCN2 in spinal astrocytes may be a key molecule and may be partly involved in the development of CPSP.

Abstract PO1-25-08: Evaluating the role of CDK4/6 inhibition on STAT3 activation in a transgenic mouse model of HER2-positive breast cancer

Abstract Background: The human epidermal growth factor receptor 2 (HER2) is a receptor tyrosine kinase overexpressed in approximately 20-25% of breast cancers with varying biological differences according to hormone receptor (HR) positive status. Combination of chemotherapy with dual HER2 blockade and endocrine therapy (adjuvant) or CDK4/6 inhibitor (CDK4/6i) therapy (metastatic) is standard of care for HER2-positive/HR-positive breast cancer. However, de-escalation of chemotherapy remains of significant interest given associated toxicities and, as a result, alternative therapeutic strategies are needed. One such strategy is targeting the signal transducer and activator of transcription 3 (STAT3) which is constitutively activated in the HER-2 positive setting. Moreover, there is preclinical evidence to suggest that phosphorylated STAT3 (pSTAT3) induces overexpression of cyclin D1 (CCND1), which along with CDK4 may mediate resistance to targeted therapy for HER2-positive breast cancer. However, it is unclear if pSTAT3 plays a significant role in tumorigenesis or the development of resistance to therapy in HER2-positive disease. We aim to evaluate the effect of CDK4/6i therapy with palbociclib on tumor growth in an inducible transgenic HER2-positive mouse model and the impact on pSTAT3 and cyclin D1 levels. Methods: Using an inducible transgenic mouse mammary tumor virus (MMTV) model of HER2-positive breast cancer, we evaluated STAT3 phosphorylation in tumors driven by HER2 expression in addition to the impact of CDK4/6 inhibition with palbociclib on tumorigenesis and pSTAT3 activation. To model tumor recurrence, doxycycline was withdrawn from tumor bearing mice and tumor regression was observed. Subsequently, the mice developed recurrent mammary tumors. Given recurrent tumors in this model are driven by a HER2-independent mechanism, we examined expression of cell cycle proteins together with STAT3 phosphorylation to determine association with recurrence. Result: In addition to expressing HER2, the primary tumors expressed estrogen receptor (ERα), Rb, cyclin D1, and CDK4/6 proteins. STAT3 phosphorylation was also observed. Treatment with palbociclib decreased Rb phosphorylation and decreased tumor growth compared to vehicle treated mice (%TGI 79.37% after 21 days). Furthermore, pSTAT3 levels were not altered with palbociclib therapy. When recurrent tumors were analyzed, they lacked HER2 expression but expressed cyclin D1 and CDK4/6 supporting that tumor growth is driven by cyclin D1/CDK4 pathway. Recurrent tumors also demonstrated pSTAT3 despite lack of HER2 expression suggesting that STAT3 phosphorylation in the recurrent tumors is mediated by an alternative mechanism, potentially the CDK4/6 pathway. Conclusion: We demonstrate STAT3 activation in a mouse model of HER2 driven breast cancer and show persistent activation in recurrent tumors lacking HER2 expression rendering them resistant to HER2-targeted therapy. We also demonstrate the anti-tumor effect of palbociclib in primary tumors with HER2-dependent proliferation. Taken together, our findings suggest that pSTAT3 is a viable therapeutic target and provides the rationale for combination therapy with CDK4/6 inhibition using palbociclib and STAT3 inhibition with a novel STAT3 inhibitor in HER2-positive breast cancer. This therapeutic approach may represent a potential chemotherapy de-escalation strategy. Citation Format: Taiwo Adesoye, Linjie Luo, Tuyen Bui, Serena Kim, Hannah Wingate, Debu Tripathy, Kelly Hunt, Khandan Keyomarsi. Evaluating the role of CDK4/6 inhibition on STAT3 activation in a transgenic mouse model of HER2-positive breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-25-08.

Abstract PO4-24-10: Prognostic role of SOX2 and STAT3 expression on circulating T lymphocytes and CD44+/CD24neg cells in the locally advanced and metastatic breast cancer

Abstract Introduction: Breast cancer (BC) is associated with a continuous increase in incidence, with high mortality rates in several countries. There are four immunophenotypes of BC, luminal A, luminal B, triple negative (TN), and HER2+. Some proteins in tumor cells and the tumor microenvironment are part of tumorigenesis and metastases. The CD44 molecule is considered an important marker of the inflammatory response. CD44 is present in all leukocytes and on the surface of tumor stem cells, involving tumor invasion and metastasis. Some authors have demonstrated that the signal transducer and activator of transcription 3 (STAT3) and sex-determining region Y-related group box 2 (SOX2) are related to the regulation of somatic cell division and tumorigenesis and metastasis in BC. Aim: To evaluate SOX2 and STAT3 expression on circulating T lymphocytes and CD44+/CD24neg cells in locally advanced and metastatic breast cancer. Methods: A cross-sectional study was conducted at the Hospital de Cancer de Pernambuco (HCP) and the Translational Research Laboratory of the Instituto de Medicina Integral Prof. Fernando Figueira (IMIP) from March 2017 to April 2018. Sixty-five women diagnosed with breast cancer participated in this study, aged between 28 and 64. Of these, 51 women had stage III (locally advanced) breast tumors, and 14 with metastatic disease (stage IV). There were 24 healthy women aged 18 to 65 as a control group. The analysis of CD44, SOX2, and STAT3 expression was performed by flow cytometry. Results: elevated levels of CD44+/CD24neg cells and CD44+/CD24neg/SOX2+ cells were observed in the blood of BC patients with luminal B, HER2+, and TN compared to the control group (p< 0.0001). Low CD44+/CD24neg/STAT3+ levels in the patient's blood compared to the control group. Elevated CD44+/CD24neg and CD44+/CD24neg/STAT3+ cells were observed in locally advanced BC compared to metastatic group (p < 0.05). Patients with TNBC had elevated SOX2+T lymphocyte levels compared to luminal B and HER2+ subtypes groups (p< 0.05). HER2+ patients had low levels of T lymphocytes and SOX2+T cells compared to controls and luminal A groups (p < 0.05). High levels of total T cells (p=0.0007) and low SOX2+T lymphocytes (p=0.02) in locally advanced compared to metastatic disease (stage IV). Elevated levels of SOX2+T lymphocytes in patients with negative lymph nodes (N0) compared to N1 and N2 groups (p=0.004 and p < 0.0001, respectively). High levels of CD44+/CD24negSTAT3+ cells and T lymphocytes and low levels of STAT3+T lymphocytes in locally advanced TN subtype (stage III) compared to metastatic (stage IV). Conclusion: SOX2 and STAT3 expression on circulating T lymphocytes and CD44+/CD24neg cells in peripheral blood are prognostic roles in breast cancer. SOX2 and STAT3 expression are potential predictive biomarkers of disease progression in breast cancer regardless of tumor subtype. Investigating these biomarkers in peripheral blood has some advantages because peripheral blood collection is less invasive, easy to access, and allows evaluation at diagnosis, during treatment, and in cases of recurrence. Citation Format: Denise Viana, Victor Andrade, Marcelo Salgado, Carolina Vasconcelos, Leuridan Torres. Prognostic role of SOX2 and STAT3 expression on circulating T lymphocytes and CD44+/CD24neg cells in the locally advanced and metastatic breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-24-10.

Renal epithelial-derived miR-17~92 inhibits STAT3 signaling, serving a sex-specific and renoprotective role in the development of AKI

Prerenal acute kidney injury (AKI) is a sudden loss of kidney excretory function from reduced blood flow to the kidney. Sex differences in the degree of injury have been recognized, the causes of which are ill-defined. While a role for miRs (microRNAs) in AKI has been recognized, there are no reports of sex differences in miR regulation after injury. Here we investigated sex differences in miR regulation in proximal tubular epithelial cells during AKI with IRI (ischemia reperfusion injury) in vivo and miR regulation of signal transducer and activator of transcription 3 (STAT3) signaling in vitro. We hypothesize that sex-differentially expressed miR-17~92 serves as a negative regulator of STAT3 signaling, repressing proinflammatory signaling in tubular epithelium during AKI. We recapitulated the phenotype that males have a higher level of injury compared to females with proportional intensity and duration of IRI in a murine AKI model. C57BL/6J mice underwent 25 minutes of unilateral IRI with a contralateral nephrectomy and sacrificed 18 hours post-reperfusion. Injured male tubules showed a significant increase in Kidney injury molecule-1 (Kim-1) expression (n³3, fold change=75.28 ± 35.92) whereas injured females showed no change, confirming that injured males experience a higher level of tubular injury than females with a matched degree of ischemia. Control female tubules showed significantly higher baseline expression of miR-17~92 compared to control males (n ³ 5, difference between means ± SEM: miR-17a, 2.337 ± 0.6322; miR-18a, 5.841 ± 2.008; miR-19a, 5.041 ± 1.232; miR- 19b, 3.826 ± 0.9791; miR-20a, 3.826 ± 1.053; miR-92a, 5.627 ± 1.588). MiR-17~92 expression in injured male tubules significantly increased compared to male controls. Even after this increase, miR-17~92 expression in male tubules was lower compared to miR-17~92 in injured females. Mir-17~92 is predicted to target STAT3 and components of the interleukin-6 (IL6)/STAT3 pathway. qPCR showed a significant increase in Stat3 expression after IRI in both sexes, but only a significant increase in IL6 and heme oxygenase-1 in injured males. To investigate miR regulation of STAT3 in vitro, we used a human proximal tubule cell line (HK2) model. Recombinant IL6 induced STAT3 protein expression and phosphorylation, and increased miR-17~92 expression. By altering miR-17~92 expression in HK2 cells we demonstrated that expression of STAT3 in response to IL6 is regulated, in part, by these miRs. These data provide the first example of sex-differential miR regulation in response to IRI. The elevated baseline expression of miR-17~92 in the female mice may provide a novel mechanism to account for sex-differences in IRI-AKI and may form part of the mechanism to protect female kidney epithelia from IRI and AKI. This work is supported by the NIH (DK102843 to MBB), (NIH R01DK102843-08S1 to AS), NIH (DK137419 and DK125015 to JH) and NIH (5R01DK131991 and 5R01DK064005 to RT). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Inhibition of STAT3 by S3I-201 suppress peritoneal fibroblast phenotype conversion and alleviate peritoneal fibrosis.

Peritoneal fibrosis is a common pathological response to long-term peritoneal dialysis (PD) and a major cause for PD discontinuation. Understanding the cellular and molecular mechanisms underlying the induction and progression of peritoneal fibrosis is of great interest. In our study, invitro study revealed that signal transducer and activator of transcription 3 (STAT3) is a key factor in fibroblast activation and extracellular matrix (ECM) synthesis. Furthermore, STAT3 induced by IL-6 trans-signalling pathway mediate the fibroblasts of the peritoneal stroma contributed to peritoneal fibrosis. Inhibition of STAT3 exerts an antifibrotic effect by attenuating fibroblast activation and ECM production with an invitro co-culture model. Moreover, STAT3 plays an important role in the peritoneal fibrosis in an animal model of peritoneal fibrosis developed in mice. Blocking STAT3 can reduce the peritoneal morphological changes induced by chlorhexidine gluconate. In conclusion, our findings suggested STAT3 signalling played an important role in peritoneal fibrosis. Therefore, blocking STAT3 might become a potential treatment strategy in peritoneal fibrosis.

Immunotherapeutic hydrogel for co-delivery of STAT3 siRNA liposomes and lidocaine hydrochloride for postoperative comprehensive management of NSCLC in a single application

Despite standard treatment for non-small cell lung cancer (NSCLC) being surgical resection, cancer recurrence and complications, such as induction of malignant pleural effusion (MPE) and significant postoperative pain, usually result in treatment failure. In this study, an alginate-based hybrid hydrogel (SOG) is developed that can be injected into the resection surface of the lungs during surgery. Briefly, endoplasmic reticulum-modified liposomes (MSLs) pre-loaded with the signal transducer and activator of transcription 3 (STAT3) small interfering RNA and lidocaine hydrochloride are encapsulated in SOG. Once applied, MSLs strongly downregulated STAT3 expression in the tumor microenvironment, resulting in the apoptosis of lung cancer cells and polarization of tumor-associated macrophages towards the M1-like phenotype. Meanwhile, the release of lidocaine hydrochloride (LID) was beneficial for pain relief and natural killer cell activation. Our data demonstrated MSL@LID@SOG not only efficiently inhibited tumor growth but also potently improved the quality of life, including reduced MPE volume and pain relief in orthotopic NSCLC mouse models, even with a single administration. MSL@LID@SOG shows potential for comprehensive clinical management upon tumor resection in NSCLC, and may alter the treatment paradigms for other cancers.

Abstract 2056: Impaired Cellular Metabolic Adaptations In Autosomal-Dominant Hyper-IgE Syndrome: Possible Implications To Deficient Angiogenesis And Wound Healing

Background: Autosomal dominant Hyper-IgE syndrome (AD-HIES; Job’s syndrome) is caused by dominant negative mutations in signal transducer and activator of transcription 3 (STAT3). Patients present with immunodeficiency accompanied by severe non-immunological features including poor post infection lung healing, subsequent pulmonary failure, and skeletal, connective tissue, and vascular abnormalities including arterial tortuosity and aneurisms which can lead to myocardial infarction and subarachnoid hemorrhage. HIF1a-dependent deficient angiogenesis has been implicated in the abnormal wound healing response of AD-HIES. Both STAT3 and HIF1a are major regulators of cellular metabolism. In this study we are testing the hypothesis that dysregulation of cellular metabolic pathways may contribute to AD-HIES pathophysiology. Methods: We used skin fibroblasts (SF) from 4 AD-HIES patients and 4 normal volunteers. To investigate ability of the cells to adapt and function in nutrient-deficient conditions (to model tissue damages disrupting normal tissue perfusion) we exposed them to a culture media lacking glucose, pyruvate and glutamine (deficient media). We used a live imaging approach (IncucyteS3 System, Sartorius) to analyze cell proliferation, reactive oxygen species (ROS), cell death, and wound closing ability (scratch-wound assay). Results: In deficient media, both AD-HIES and control SF decreased their proliferation rate. While control SF adapted, AD-HIES SF showed decreased survival after prolong nutrient deprivation. Level of ROS, measured at 12, 24, 48h in deficient media was 25% higher in AD-HIES SF (n=8, P=0.003). We used a scratch-wound assay to assess the ability of fibroblasts to migrate and close the wound after 48h of adaptation to deficient media. In full media, both control and AD-HIES fibroblast completely closed the wound within 36h. In deficient media, wound closure was delayed to much higher degree by AD-HIES fibroblasts (60±14% closure by control SF vs 18±9% by AD-HIES SF, n=4, P=0.016). Conclusions: Adaptive remodeling of cellular metabolism is impaired in AD-HIES SF that may contribute to deficient angiogenesis and poor wound healing, suggesting possible therapeutic targets within cellular metabolic pathways.

The therapeutic effect and targets of herba Sarcandrae on breast cancer and the construction of a prognostic signature consisting of inflammation-related genes

BackgroundThe prevalence of breast cancer (BRCA), which is common among women, is on the rise. This study applied network pharmacology to explore the potential mechanism of action of herba sarcandrae in BRCA and construct a prognostic signature composed of inflammation-related genes. MethodsThe active ingredients of herba sarcandrae were screened using the SymMap, TCMID, and TCMSP platforms, and the molecular targets were determined in the UniProt database. The “drug-active compound-potential target” network was established with Cytoscape 3.7.2. The molecular targets were subjected to disease ontology, gene ontology (GO), and Kyoto Encyclopedia of Genes (KEGG) analyses. AutoDock software was used for molecular docking. Differentially expressed genes (DEGs) related to inflammation were obtained from the BRCA Cancer Genome Atlas (TCGA) database. In the training cohort, the univariate Cox regression model was applied to preliminarily screen prognostic genes. A multigene signature was built by the least absolute shrinkage and selection operator (LASSO) regression model, followed by validation through Kaplan‒Meier, Cox, and receiver operating characteristic (ROC) analyses. ResultsForty-one active compounds were identified, and 265 therapeutic targets for herba sarcandrae were predicted. GO enrichment results revealed significant enrichment of biological processes, such as response to xenobiotic stimuli, response to nutrient levels, and response to lipopolysaccharide. KEGG analysis revealed significant enrichment of pathways such as AGE-RAGE and chemical carcinogenesis receptor activation signaling pathways. In addition, the herbs Marc-Andre and rutin were shown to mediate BRCA cell proliferation and apoptosis via the interferon regulatory factor 1 (IRF1)/signal transducer and activator of transcription 3 (STAT3)/programmed death-ligand 1 (PD-L1) pathway. Sixteen inflammatory signatures, including BST2, GPR132, IL12B, IL18, IL1R1, IL2RB, IRF1, and others, were constructed, and the risk score was found to be a strong independent prognostic factor for overall survival in BRCA patients. The 16-inflammation signature was associated with several clinical features (age, clinical stage, T, and N classifications) and could reflect immune cell infiltration in tumor microenvironments with different immune cells. ConclusionsHerba sarcandrae and rutin were shown to mediate BRCA cell proliferation and apoptosis via the IRF1/STAT3/PD-L1 pathway, and the 16-member inflammatory signature might be a novel biomarker for predicting BRCA patient prognosis, providing more accurate guidance for clinical treatment prognosis evaluation and having important reference value for individualized treatment selection.

A formulation of combined Poria cocos and Cordyceps militaris rice ameliorates depressive-like effects by downregulating p38 MAPK signaling pathways

Background and aimPoria cocos (PC) is traditional Chinese medicine with sedative, diuretic, and tonic properties. Cordyceps militaris rice (CMR) is a matrix used for the solid-state culture of C. militaris, which has been used for anti-angiogenetic and anti-inflammation effects. To investigate a formulation of combined Poria cocos and Cordyceps militaris rice (PC-CMR) alleviates anxiety behaviours and depressive-like effects for the first time. Experimental procedureAfter five-week of stress, rats were induced by unpredictable chronic mild stress (UCMS) treated with PC-CMR formulation. Then, rats underwent various behavior tests, testing serum inflammatory mediators by enzyme-linked immunosorbent assays (ELISA), evaluated monoamines by high-performance liquid chromatography (HPLC) analysis, and protein expression by western blotting. ResultsTreatment with doses of formulated PC-CMR reversed sucrose preference and increased amount of time spent on the open arms in rat behavioral tests. The formulated PC-CMR significantly reduced glutamate content and turnover rates of serotonin and dopamine in the prefrontal cortex of rats. In the inflammation-related pathway, PC-CMR decreased interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) levels in serum and downregulated the expression of p38 mitogen-activated protein kinase (p38 MAPK), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in the prefrontal cortex and signal transducer and activator of transcription 3 (STAT3), and indoleamine 2,3-dioxygenase (IDO) in the amygdala. ConclusionOur findings suggest that the formulated PC-CMR could have antidepressive and anxiolytic effects by modulating neurotransmitter levels and reducing inflammation.

Exploration of novel isoxazole-fused quinone derivatives as anti-colorectal cancer agents through inhibiting STAT3 and elevating ROS level

Colorectal cancer (CRC) is trending to be a major health problem throughout the world. Therapeutics with dual modes of action have shown latent capacity to create ideal anti-tumor activity. Signal transducer and activator of transcription 3 (STAT3) has been proved to be a potential target for the development of anti-colon cancer drug. In addition, modulation of tumor redox homeostasis through deploying exogenous reactive oxygen species (ROS)-enhancing agents has been widely applied as anti-tumor strategy. Thus, simultaneously targeting STAT3 and modulation ROS balance would offer a fresh avenue to combat CRC. In this work, we designed and synthesized a novel series of isoxazole-fused quinones, which were evaluated for their preliminary anti-proliferative activity against HCT116 cells. Among these quinones, compound 41 exerted excellent in vitro anti-tumor effect against HCT116 cell line with an IC50 value of 10.18 ± 0.4 nM. Compound 41 was proved to bind to STAT3 by using Bio-Layer Interferometry (BLI) assay, and can significantly inhibit phosphorylation of STAT3. It also elevated ROS of HCT116 cells by acting as a substrate of NQO1. Mitochondrial dysfunction, apoptosis, and cell cycle arrest, which was caused by compound 41, might be partially due to the inhibition of STAT3 phosphorylation and ROS production induced by 41. Moreover, it exhibited ideal anti-tumor activity in human colorectal cancer xenograft model and good safety profiles in vivo. Overall, this study provided a novel quinone derivative 41 with excellent anti-tumor activity by inhibiting STAT3 and elevating ROS level, and gave insights into designing novel anti-tumor therapeutics by simultaneously modulation of STAT3 and ROS.

Identification of Novel STAT3 Dimerization Inhibitor Through Structure-Based Virtual Screening for Cancer Management

Background: Signal transducer and activator of transcription 3 (STAT3) is a transcription factor that controls cell proliferation, differentiation, angiogenesis, and immunological responses. In many human malignancies, abnormal STAT3 activation promotes tumor growth via oncogenic gene expression, resulting in tumor malignancy. Many drugs with clinically authorized analogues that are used as STAT3 inhibitors for cancer therapy have several drawbacks in terms of stability and toxicity.Methods: This study used PyRx 0.8 tool to screen the Traditional Chinese Medicine (TCM) database of about 32,364 commercially available natural compounds in order to identify new STAT3 inhibitors. Physicochemical and ADME properties of selected compounds were estimated using Datawarrior and SwissADME.Result: The top 20 compounds were initially chosen based on their strong binding affinities with STAT3. Lipinski and Vaber tools were used to filter the top 20 compounds, yielding the top 6 compounds. The compounds ZINC85542844, ZINC4098720, ZINC85543599, ZINC85593523, ZINC85593528, and ZINC85593537 were passed through these filters. These compounds were found to interact with active site STAT3 residues and have several amino acid interactions in common with the control compound (STX0119).Conclusion: This study suggests that the compounds ZINC85542844, ZINC4098720, ZINC85543599, ZINC85593523, ZINC85593528, and ZINC85593537 could be used as a lead for the development of novel STAT3 inhibitors. However, further experimental validation is required to optimized them as STAT3 inhibitors.Keywords: STAT3; Transcription factor; Natural compounds; Cancer; Virtual screening