Hypervolemia in Dialysis Patients Impairs STAT3 Signaling and Upregulates miR-142-3p: Effects on IL-10 and IL-6.

Fluid overload in hemodialysis patients (HD) has been proven to be associated with inflammation. Elevated levels of the pro-inflammatory cytokine interleukin-6 (IL-6) appear to be inadequately counterbalanced by the anti-inflammatory cytokine interleukin-10 (IL-10). We initiated a cross-sectional study enrolling 40 HD patients who were categorized by a bioimpedance measurement in normovolemic (N; 23) and hypervolemic (H; 17) groups to test whether IL-10- and IL-6-related signal transduction pathways (signal transducer of transcript 3: STAT3) and/or a post-transcriptional regulating mechanism (miR-142) are impaired by hypervolemia. IL-10/IL-6 transcript and protein production by PBMCs (peripheral blood mononuclear cells) were determined. Phospho-flow cytometry was used to detect the phosphorylated forms of STAT3 (pY705 and pS727). miR-142-3p/5p levels were detected by qPCR. Hypervolemic patients were older, more frequently had diabetes, and showed higher CRP levels. IL-10 transcripts were elevated in H patients but not IL-10 protein levels. In spite of the elevated mRNA expression of the suppressor of cytokine expression 3 (SOCS3), IL-6 mRNA and protein expression were increased in immune cells of H patients. The percentage of cells staining positive for STAT3 (pY705) were comparable in both groups; in STAT3 (pS727), however, the signal needed for full transactivation was decreased in H patients. miR-142-3p, a proven target of IL-10 and IL-6, was significantly elevated in H patients. Insufficient phosphorylation of STAT3 may impair inflammatory and anti-inflammatory cytokine signaling. How far degradative mechanisms induced by elevated miR-142-3p levels contribute to an inefficient anti-inflammatory IL-10 signaling remains elusive.

Nuclear autoantigenic sperm protein facilitates glioblastoma progression and radioresistance by regulating the ANXA2/STAT3 axis.

AIMS: Although radiotherapy is a core treatment modality for various human cancers, including glioblastoma multiforme (GBM), its clinical effects are often limited by radioresistance. The specific molecular mechanisms underlying radioresistance are largely unknown, and the reduction of radioresistance is an unresolved challenge in GBM research. METHODS: We analyzed and verified the expression of nuclear autoantigenic sperm protein (NASP) in gliomas and its relationship with patient prognosis. We also explored the function of NASP in GBM cell lines. We performed further mechanistic experiments to investigate the mechanisms by which NASP facilitates GBM progression and radioresistance. An intracranial mouse model was used to verify the effectiveness of combination therapy. RESULTS: NASP was highly expressed in gliomas, and its expression was negatively correlated with the prognosis of glioma. Functionally, NASP facilitated GBM cell proliferation, migration, invasion, and radioresistance. Mechanistically, NASP interacted directly with annexin A2 (ANXA2) and promoted its nuclear localization, which may have been mediated by phospho-annexin A2 (Tyr23). The NASP/ANXA2 axis was involved in DNA damage repair after radiotherapy, which explains the radioresistance of GBM cells that highly express NASP. NASP overexpression significantly activated the signal transducer and activator of transcription 3 (STAT3) signaling pathway. The combination of WP1066 (a STAT3 pathway inhibitor) and radiotherapy significantly inhibited GBM growth in vitro and in vivo. CONCLUSION: Our findings indicate that NASP may serve as a potential biomarker of GBM radioresistance and has important implications for improving clinical radiotherapy.

PDP1 promotes the progression of breast cancer through STAT3 pathway.

This study aimed to investigate the expression pattern and mechanisms of Pyruvate Dehydrogenase Phosphatase Catalytic Subunit 1 (PDP1) in the progression of breast cancer (BC). PDP1, known for its involvement in cell energy metabolism, was found to be overexpressed in BC tissues. Notably, low PDP1 expression aligns with improved overall survival (OS) in BC patients. In this study, we found that PDP1 was overexpressed among BC tissues and low PDP1 expression showed a better prognosis for the patients with BC. PDP1 knockdown suppressed cell amplification and migration and triggered cell apoptosis in BC cells. In vivo assessments through a xenograft model unveiled the pivotal role and underlying mechanisms of PDP1 knockdown. RNA sequencing and kyoto encyclopedia of genes and genomes analysis of RNAs from PDP1 knockdown and normal MCF7 cells revealed 1440 differentially expressed genes, spotlighting the involvement of the JAK/STAT3 signaling pathway in BC progression. Western blot results implied that PDP1 knockdown led to a loss of p-STAT3, whereas overexpression of PDP1 induced the p-STAT3 expression. Cell counting kit-8 assay showed that PDP1 overexpression significantly raised MDA-MB-231 and MCF7 cell viability while STAT3 inhibitor S3I-201 recovered the cell growth to normal level. To summarize, PDP1 promotes the progression of BC through STAT3 pathway by regulating p-STAT3. The findings contribute to understanding the molecular mechanisms underlying BC progression, and opening avenues for targeted therapeutic approaches.

IL-17 induces NSCLC cell migration and invasion by elevating MMP19 gene transcription and expression through the interaction of p300-dependent STAT3-K631 acetylation and its Y705-phosphorylation.

The cancer cell metastasis is a major death reason for patients with non-small cell lung cancer (NSCLC). Although researchers have disclosed that interleukin 17 (IL-17) can increase matrix metalloproteinases (MMPs) induction causing NSCLC cell metastasis, the underlying mechanism remains unclear. In the study, we found that IL-17 receptor A (IL-17RA), p300, p-STAT3, Ack-STAT3, and MMP19 were up-regulated both in NSCLC tissues and NSCLC cells stimulated with IL-17. p300, STAT3 and MMP19 overexpression or knockdown could raise or reduce IL-17-induced p-STAT3, Ack-STAT3 and MMP19 level as well as the cell migration and invasion. Mechanism investigation revealed that STAT3 and p300 bound to the same region (-544 to -389 nt) of MMP19 promoter, and p300 could acetylate STAT3-K631 elevating STAT3 transcriptional activity, p-STAT3 or MMP19 expression and the cell mobility exposed to IL-17. Meanwhile, p300-mediated STAT3-K631 acetylation and its Y705-phosphorylation could interact, synergistically facilitating MMP19 gene transcription and enhancing cell migration and invasion. Besides, the animal experiments exhibited that the nude mice inoculated with NSCLC cells by silencing p300, STAT3 or MMP19 gene plus IL-17 treatment, the nodule number, and MMP19, Ack-STAT3, or p-STAT3 production in the lung metastatic nodules were all alleviated. Collectively, these outcomes uncover that IL-17-triggered NSCLC metastasis involves up-regulating MMP19 expression via the interaction of STAT3-K631 acetylation by p300 and its Y705-phosphorylation, which provides a new mechanistic insight and potential strategy for NSCLC metastasis and therapy.

The endonuclease FEN1 mediates activation of STAT3 and facilitates proliferation and metastasis in breast cancer.

BACKGROUND: The metastasis accounts for most deaths from breast cancer (BRCA). Understanding the molecular mechanisms of BRCA metastasis is urgently demanded. Flap Endonuclease 1 (FEN1), a pivotal factor in DNA metabolic pathways, contributes to tumor growth and drug resistance, however, little is known about the role of FEN1 in BRCA metastasis. METHODS AND RESULTS: In this study, FEN1 expression and its clinical correlation in BRCA were investigated using bioinformatics, showing being upregulated in BRCA samples and significant relationships with tumor stage, node metastasis, and prognosis. Immunohistochemistry (IHC) staining of local BRCA cohort indicated that the ratio of high FEN1 expression in metastatic BRCA tissues rose over that in non-metastatic tissues. The assays of loss-of-function and gain-of-function showed that FEN1 enhanced BRCA cell proliferation, migration, invasion, xenograft growth as well as lung metastasis. It was further found that FEN1 promoted the aggressive behaviors of BRCA cells via Signal Transducer and Activator of Transcription 3 (STAT3) activation. Specifically, the STAT3 inhibitor Stattic thwarted the FEN1-induced enhancement of migration and invasion, while the activator IL-6 rescued the decreased migration and invasion caused by FEN1 knockdown. Additionally, overexpression of FEN1 rescued the inhibitory effect of nuclear factor-κB (NF-κB) inhibitor BAY117082 on phosphorylated STAT3. Simultaneously, the knockdown of FEN1 attenuated the phosphorylation of STAT3 promoted by the NF-κB activator tumor necrosis factor α (TNF-α). CONCLUSIONS: These results indicate a novel mechanism that NF-κB-driven FEN1 contributes to promoting BRCA growth and metastasis by STAT3 activation.

STAT3 is a genetic modifier of TGF-beta induced EMT in KRAS mutant pancreatic cancer.

Oncogenic mutations in KRAS are among the most common in cancer. Classical models suggest that loss of epithelial characteristics and the acquisition of mesenchymal traits are associated with cancer aggressiveness and therapy resistance. However, the mechanistic link between these phenotypes and mutant KRAS biology remains to be established. Here, we identify STAT3 as a genetic modifier of TGF-beta-induced epithelial to mesenchymal transition. Gene expression profiling of pancreatic cancer cells identifies more than 200 genes commonly regulated by STAT3 and oncogenic KRAS. Functional classification of the STAT3-responsive program reveals its major role in tumor maintenance and epithelial homeostasis. The signatures of STAT3-activated cell states can be projected onto human KRAS mutant tumors, suggesting that they faithfully reflect characteristics of human disease. These observations have implications for therapeutic intervention and tumor aggressiveness.

Polyphyllin B inhibited STAT3/NCOA4 pathway and restored gut microbiota to ameliorate lung tissue injury in cigarette smoke-induced mice.

OBJECTIVE: Smoking was a major risk factor for chronic obstructive pulmonary disease (COPD). This study plan to explore the mechanism of Polyphyllin B in lung injury induced by cigarette smoke (CSE) in COPD. METHODS: Network pharmacology and molecular docking were applied to analyze the potential binding targets for Polyphyllin B and COPD. Commercial unfiltered CSE and LPS were used to construct BEAS-2B cell injury in vitro and COPD mouse models in vivo, respectively, which were treated with Polyphyllin B or fecal microbiota transplantation (FMT). CCK8, LDH and calcein-AM were used to detect the cell proliferation, LDH level and labile iron pool. Lung histopathology, Fe3+ deposition and mitochondrial morphology were observed by hematoxylin-eosin, Prussian blue staining and transmission electron microscope, respectively. ELISA was used to measure inflammation and oxidative stress levels in cells and lung tissues. Immunohistochemistry and immunofluorescence were applied to analyze the 4-HNE, LC3 and Ferritin expression. RT-qPCR was used to detect the expression of FcRn, pIgR, STAT3 and NCOA4. Western blot was used to detect the expression of Ferritin, p-STAT3/STAT3, NCOA4, GPX4, TLR2, TLR4 and P65 proteins. 16S rRNA gene sequencing was applied to detect the gut microbiota. RESULTS: Polyphyllin B had a good binding affinity with STAT3 protein, which as a target gene in COPD. Polyphyllin B inhibited CS-induced oxidative stress, inflammation, mitochondrial damage, and ferritinophagy in COPD mice. 16S rRNA sequencing and FMT confirmed that Akkermansia and Escherichia_Shigella might be the potential microbiota for Polyphyllin B and FMT to improve CSE and LPS-induced COPD, which were exhausted by the antibiotics in C + L and C + L + P mice. CSE and LPS induced the decrease of cell viability and the ferritin and LC3 expression, and the increase of NCOA4 and p-STAT3 expression in BEAS-2B cells, which were inhibited by Polyphyllin B. Polyphyllin B promoted ferritin and LC3II/I expression, and inhibited p-STAT3 and NCOA4 expression in CSE + LPS-induced BEAS-2B cells. CONCLUSION: Polyphyllin B improved gut microbiota disorder and inhibited STAT3/NCOA4 pathway to ameliorate lung tissue injury in CSE and LPS-induced mice.

STAT3 couples activated tyrosine kinase signaling to the oncogenic core transcriptional regulatory circuitry of anaplastic large cell lymphoma.

Anaplastic large cell lymphoma (ALCL) is an aggressive, CD30+ T cell lymphoma of children and adults. ALK fusion transcripts or mutations in the JAK-STAT pathway are observed in most ALCL tumors, but the mechanisms underlying tumorigenesis are not fully understood. Here, we show that dysregulated STAT3 in ALCL cooccupies enhancers with master transcription factors BATF3, IRF4, and IKZF1 to form a core regulatory circuit that establishes and maintains the malignant cell state in ALCL. Critical downstream targets of this network in ALCL cells include the protooncogene MYC, which requires active STAT3 to facilitate high levels of MYC transcription. The core autoregulatory transcriptional circuitry activity is reinforced by MYC binding to the enhancer regions associated with STAT3 and each of the core regulatory transcription factors. Thus, activation of STAT3 provides the crucial link between aberrant tyrosine kinase signaling and the core transcriptional machinery that drives tumorigenesis and creates therapeutic vulnerabilities in ALCL.

IL-1ß induced down-regulation of miR-146a-5p promoted pyroptosis and apoptosis of corneal epithelial cell in dry eye disease through targeting STAT3.

AIM: To elaborate the underlying mechanisms by which IL-1ß promote progression of Dry eye disease(DED) through effect on pyroptosis and apoptosis of corneal epithelial cells(CECs). METHODS: 400 mOsM solutions were used to establish the DED model (hCECs- DED). RT-qPCR was performed to measure IL-1ß mRNA and miR-146a-5p in CECs. Western blotting was performed to measure STAT3, GSDMD, NLRP3, and Caspase-1 levels. Cell counting kit-8 assay was adopted to check cell viability. Apoptosis was detected by flow cytometry. ELISAs were performed to determine IL-18, IL-33 and LDH. The luciferase test detects targeting relationships. RESULTS: After treatment with 400 mOsM solution, cell viability decreased and apoptosis increased. Compared with hCECs, IL-1ß was increased and miR-146a-5p was decreased in hCECs-DED. At the same time, GSDMD, NLRP3, Caspase-1, IL-18, IL-33 and LDH were significantly higher in hCECs-DED than in hCECs, while IL-1ß silencing reversed this effect. In addition, IL-1ß negatively regulated miR-146a-5p. MiR-146a-5p mimics eliminated the inhibition of hCECs-DED pyroptosis and apoptosis caused by IL-1ß silencing. At the same time, miR-146a-5p reduced STAT3 levels in hCECs. CONCLUSION: Highly expressed IL-1ß promoted pyroptosis and apoptosis of hCECs- DED through downregulated miR-146a-5p and inhibited STAT3.

Exosomal lncRNA HEIH, an essential communicator for hepatocellular carcinoma cells and macrophage M2 polarization through the miR-98-5p/STAT3 axis.

Part of human long noncoding RNAs (lncRNAs) has been elucidated to play an essential role in the carcinogenesis and progression of hepatocellular carcinoma (HCC), a type of malignant tumor with poor outcomes. Tumor-derived exosomes harboring lncRNAs have also been implicated as crucial mediators to orchestrate biological functions among neighbor tumor cells. The recruitment of tumor-associated macrophages (TAMs) exerting M2-like phenotype usually indicates the poor prognosis. Yet, the precise involvement of tumor-derived lncRNAs in cross-talk with environmental macrophages has not been fully identified. In this study, we reported the aberrantly overexpressed HCC upregulated EZH2-associated lncRNA (HEIH) in tumor tissues and cell lines was positively correlated with poor prognosis, as well as enriched exosomal HEIH levels in blood plasma and cell supernatants. Besides, HCC cell-derived exosomes transported HEIH into macrophages for triggering macrophage M2 polarization, thereby in turn promoting the proliferation, migration, and invasion of HCC cells. Mechanistically, HEIH acted as a miRNA sponge for miR-98-5p to up-regulate STAT3, which was then further verified in the tumor xenograft models. Collectively, our study provides the evidence for recognizing tumor-derived exosomal lncRNA HEIH as a novel regulatory function through targeting miR-98-5p/STAT3 axis in environmental macrophages, which may shed light on the complicated tumor microenvironment among tumor and immune cells for HCC treatment.

Investigating the association between the tissue expression of miRNA-101, JAK2/STAT3 with TNF-α, IL-6, IL-1ß, and IL-10 cytokines in the ulcerative colitis patients.

BACKGROUND: Ulcerative colitis (UC) is a chronic inflammatory bowel disease caused by numerous factors, such as immune system dysfunction and genetic factors. MicroRNAs (miRNAs) play a crucial role in UC pathogenesis, particularly via the JAK-STAT pathway. Our aim was to investigate the association between miRNA-101 and JAK2-STAT3 signaling pathway with inflammatory cytokines in UC patients. METHODS: We enrolled 35 UC patients and 35 healthy individuals as the control group, referred to Shariati Hospital, Tehran, Iran. Patients were diagnosed based on clinical, laboratory, histological, and colonoscopy criteria. RNA and protein extracted from tissue samples. Real-time PCR was used to assess the expression levels of miRNA-101, interleukin (IL)-1ß, IL-6, tumor necrosis factor (TNF)-α, and IL-10 genes, while western blot was employed to measure levels of P-STAT3, total STAT3, and JAK2 proteins. RESULTS: Expression of pro-inflammatory cytokines TNF-α, IL-1ß, and IL-6 significantly increased, while the expression of IL-10 significantly decreased in the case group versus controls. Additionally, miRNA-101 expression was significantly higher in UC patients. A significant correlation between miRNA-101 and IL-6 expression was observed, indicating their relationship and possible impact on cell signaling pathways, JAK2-STAT3. No significant changes were observed in phosphorylated and total STAT3 and JAK2 protein expression. CONCLUSION: This study provides evidence of increased miRNA-101 expression in UC tissue, suggesting a potential correlation between miRNA-101 and IL-6 expression and their involvement in the JAK2-STAT3 pathway. The study confirms alterations in UC patients' pro-inflammatory cytokines and anti-inflammatory IL-10. However, further investigations are needed to understand the exact role of miRNA-101 in UC pathogenesis fully.

The role of JAK2/STAT3 pathway in non-cytotoxic concentrations of DON-induced aggravation of inflammatory response in IL-10 deficient RAW264.7 cells.

Deoxynivalenol (DON) as a mycotoxin was commonly found in food and cereals which can affect immune function and inflammatory response. The majority of foods contain DON at levels below the official limit. This study aimed to evaluate the effects of non-cytotoxic concentration of DON on inflammation and its mechanisms using the IL-10 gene-silenced RAW264.7 cell model. The results showed that a non-cytotoxic concentration of DON at 25 ng/ml aggravated IL-10 knockdown-induced inflammation, which was manifested by increasing IL-1ß and TNF-α mRNA expression, migration and phagocytosis, decreasing IL-10 mRNA expression, and enhancing JAK2/STAT3 phosphorylation. Adding JAK2 inhibitor AG490 attenuated the aggravating effect of DON on IL-10 knockdown-induced inflammation. In conclusion, a non-cytotoxic concentration of DON enhances the inflammatory response through the JAK2/STAT3 signaling pathway when inflammation occurs in the body. These results indicated that non-cytotoxic concentrations of DON could aggravate inflammation when inflammation was induced by IL-10 knockdown, which increases vigilance against DON contamination at low concentration especially when an animal's body has inflammation.

MicroRNA-221-3p inhibits the inflammatory response of keratinocytes by regulating the DYRK1A/STAT3 signaling pathway to promote wound healing in diabetes.

Diabetic foot ulcer (DFU), a serious complication of diabetes, remains a clinical challenge. MicroRNAs affect inflammation and may have therapeutic value in DFU. Here, we find that an miR-221-3p mimic reduces the inflammatory response and increases skin wound healing rates in a mouse model of diabetes, whereas miR-221-3p knockout produced the opposite result. In human keratinocytes cells, miR-221-3p suppresses the inflammatory response induced by high glucose. The gene encoding DYRK1A is a target of miR-221-3p. High glucose increases the expression of DYRK1A, but silencing DYRK1A expression decreases high glucose-induced inflammatory cytokine release via dephosphorylation of STAT3, a substrate of DYRK1A. Application of miR-221-3p mimic to human keratinocytes cells not only decreases DYRK1A expression but also inhibits high glucose-induced production of inflammatory cytokines to promote wound healing. This molecular mechanism whereby miR-221-3p regulates inflammation through the DYRK1A/STAT3 signaling pathway suggests targets and therapeutic approaches for treating DFU.

Tumor-associated macrophages drive glycolysis through the IL-8/STAT3/GLUT3 signaling pathway in pancreatic cancer progression.

Glycolytic metabolism is a hallmark of pancreatic ductal adenocarcinoma (PDAC), and tumor-associated stromal cells play important roles in tumor metabolism. We previously reported that tumor-associated macrophages (TAMs) facilitate PDAC progression. However, little is known about whether TAMs are involved in regulating glycolysis in PDAC. Here, we found a positive correlation between CD68+ TAM infiltration and FDG maximal standardized uptake (FDG SUVmax) on PET-CT images of PDAC. We discovered that the glycolytic gene set was prominently enriched in the high TAM infiltration group through Gene Set Enrichment Analysis using The Cancer Genome Atlas database. Mechanistically, TAMs secreted IL-8 to promote GLUT3 expression in PDAC cells, enhancing tumor glycolysis both in vitro and in vivo, whereas this effect could be blocked by the IL-8 receptor inhibitor reparixin. Furthermore, IL-8 promoted the translocation of phosphorylated STAT3 into the nucleus to activate the GLUT3 promoter. Overall, we demonstrated that TAMs boosted PDAC cell glycolysis through the IL-8/STAT3/GLUT3 signaling pathway. Our cumulative findings suggest that the abrogation of TAM-induced tumor glycolysis by reparixin might exhibit an antitumor impact and offer a potential therapeutic target for PDAC.

Role of STAT3 in cancer cell epithelial­mesenchymal transition (Review).

Since its discovery, the role of the transcription factor, signal transducer and activator of transcription 3 (STAT3), in both normal physiology and the pathology of numerous diseases, including cancer, has been extensively studied. STAT3 is aberrantly activated in different types of cancer, fulfilling a critical role in cancer progression. The biological process, epithelial­mesenchymal transition (EMT), is indispensable for embryonic morphogenesis. During the development of cancer, EMT is hijacked to confer motility, tumor cell stemness, drug resistance and adaptation to changes in the microenvironment. The aim of the present review was to outline recent advances in knowledge of the role of STAT3 in EMT, which may contribute to the understanding of the function of STAT3 in EMT in various types of cancer. Delineating the underlying mechanisms associated with the STAT3­EMT signaling axis may generate novel diagnostic and therapeutic options for cancer treatment.

IL6-STAT3-C/EBPß-IL6 positive feedback loop in tumor-associated macrophages promotes the EMT and metastasis of lung adenocarcinoma.

BACKGROUND: Lung cancer is one of the most common tumors in the world, and metastasis is one of the major causes of tumor-related death in lung cancer patients. Tumor-associated macrophages (TAMs) are a major component of the tumor microenvironment (TME) and are frequently associated with tumor metastasis in human cancers. However, the regulatory mechanisms of TAMs in lung cancer metastasis remain unclear. METHODS: Single-cell sequencing analysis of lung cancer and normal tissues from public databases and from 14 patients who underwent surgery at Zhongshan Hospital was performed. In vitro co-culture experiments were performed to evaluate the effects of TAMs on lung cancer migration and invasion. Changes in the expression of IL-6, STAT3, C/EBPΒ, and EMT pathway were verified using RT-qPCR, western blotting, and immunofluorescence. Dual luciferase reporter assays and ChIP were used to reveal potential regulatory sites on the transcription factor sets. In addition, the effects of TAMs on lung cancer progression and metastasis were confirmed by in vivo models. RESULTS: TAM infiltration is associated with tumor progression and poor prognosis. IL-6 secreted by TAMs can activate the JAK2/STAT3 pathway through autocrine secretion, and STAT3 acts as a transcription factor to activate the expression of C/EBPß, which further promotes the transcription and expression of IL-6, forming positive feedback loops for IL6-STAT3-C/EBPß-IL6 in TAMs. IL-6 secreted by TAMs promotes lung cancer progression and metastasis in vivo and in vitro by activating the EMT pathway, which can be attenuated by the use of JAK2/STAT3 pathway inhibitors or IL-6 monoclonal antibodies. CONCLUSIONS: Our data suggest that TAMs promote IL-6 expression by forming an IL6-STAT3-C/EBPß-IL6 positive feedback loop. Released IL-6 can induce the EMT pathway in lung cancer to enhance migration, invasion, and metastasis. The use of IL-6-neutralizing antibody can partially counteract the promotion of LUAD by TAMs. A novel mechanism of macrophage-promoted tumor progression was revealed, and the IL6-STAT3-C/EBPß-IL6 signaling cascade may be a potential therapeutic target against lung cancer.

MicroRNA-124 negatively regulates STAT3 to alleviate hypoxic-ischemic brain damage by inhibiting oxidative stress.

MicroRNA-124 (miR-124) is implicated in various neurological diseases; however, its significance in hypoxic-ischaemic brain damage (HIBD) remains unclear. This study aimed to elucidate the underlying pathophysiological mechanisms of miR-124 in HIBD. In our study performed on oxygen-glucose deprivation followed by reperfusion (OGD)/R-induced primary cortical neurons, a substantial reduction in miR-124 was observed. Furthermore, the upregulation of miR-124 significantly mitigated oxidative stress, apoptosis, and mitochondrial impairment. We demonstrated that miR-124 interacts with the signal transducer and activator of transcription 3 (STAT3) to exert its biological function using the dual-luciferase reporter gene assay. As the duration of OGD increased, miR-124 exhibited a negative correlation with STAT3. STAT3 overexpression notably attenuated the protective effects of miR-124 mimics, while knockdown of STAT3 reversed the adverse effects of the miR-124 inhibitor. Subsequently, we conducted an HIBD model in rats. In vivo experiments, miR-124 overexpression attenuated cerebral infarction volume, cerebral edema, apoptosis, oxidative stress, and improved neurological function recovery in HIBD rats. In summary, the neuroprotective effects of the miR-124/STAT3 axis were confirmed in the HIBD model. MiR-124 may serve as a potential biomarker with significant therapeutic implications for HIBD.

Sciellin promotes the development and progression of thyroid cancer through the JAK2/STAT3 signaling pathway.

Thyroid cancer (TC) is one of the most common endocrine tumors worldwide. Sciellin (SCEL) is involved in various disease processes, including burn wound healing and neutrophil extracellular traps (NETs); it is highly expressed in TC. However, its biological impact on TC and related mechanisms remain unclear. This study aimed to investigate the effect of SCEL on the function of human TC cell lines B-CPAP and OCUT-2C (cancer cell lines with BRAF V600E mutations). Analyses of data sets and clinical samples revealed enhanced expression of SCEL in TC than in adjacent normal tissue. SCEL knockout suppresses proliferation and cell cycle progression in TC cells, and these results were reversed by the upregulated SCEL expression in TC. SCEL knockout inhibited tumor development in xenograft mouse models. Western blot (WB) demonstrated that the expression of p-JAK2 and p-STAT3 was reduced in SCEL-knockdown TC. These results suggest that SCEL plays a key role in TC progression through the JAK2-STAT3 pathway. Therefore, SCEL can be considered a potential diagnostic biomarker and therapeutic target for TC.

Farnesoid X receptor promotes non-small cell lung cancer metastasis by activating Jak2/STAT3 signaling via transactivation of IL-6ST and IL-6 genes.

Metastasis accounts for the majority of cases of cancer recurrence and death in patients with advanced non-small cell lung cancer (NSCLC). Farnesoid X Receptor (FXR) is a bile acid nuclear receptor that was recently found to be upregulated in NSCLC tissues. However, whether and how FXR regulates NSCLC metastasis remains unclear. In the present study, it was found that FXR promoted the migration, invasion, and angiogenic ability of NSCLC cells in vitro, and increased NSCLC metastasis in a mouse model in vivo. Mechanistic investigation demonstrated that FXR specifically bound to the promoters of IL-6ST and IL-6 genes to upregulate their transcription, thereby leading to activation of the Jak2/STAT3 signaling pathway, which facilitated tumor migration, invasion, and angiogenesis in NSCLC. Notably, Z-guggulsterone, a natural FXR inhibitor, significantly reduced FXRhigh NSCLC metastasis, and decreased the expression of FXR, IL-6, IL-6ST, and p-STAT3 in the mouse model. Clinical analysis verified that FXR was positively correlated with IL-6, IL-6ST and p-STAT3 expression in NSCLC patients, and was indicative of a poor prognosis. Collectively, these results highlight a novel FXR-induced IL-6/IL-6ST/Jak2/STAT3 axis in NSCLC metastasis, and a promising therapeutic means for treating FXRhigh metastatic NSCLC.

miR-330-5p Suppress Cell Growth and Invasion via Disrupting HSF4-mediated MACC1/STAT3 Pathway in Colorectal Cancer.

BACKGROUND: Recently, miRNAs are demonstrated to restrain mRNA translation through novel pattern with bind complementary sites in the coding sequence (CDS). Heat Shock Transcription Factor 4 (HSF4) has been newly described as a tumor-associated transcription factor. Therefore, the present study intends to explore miRNAs that bind CDS region of HSF4, and identify the function of their interactions in the malignant biological behavior of colorectal cancer (CRC). METHODS: Prognostic value of HSF4 and correlation between HSF4 and MACC1 expression were estimated via bioinformatics with the Cancer Genome Atlas (TCGA) data. HSF4 and downstream MACC1/STAT3 signaling cascade was characterized by immunoblotting. To characterize the effects of miR-330-5p and HSF4 on the malignant phenotype of CRC cells by functional experiments. The binding activity of miR-330-5p to coding sequence (CDS) of HSF4 was identified using DIANA-microT-CDS algorithm and dual-luciferase reporter assay. RESULTS: HSF4 was aberrantly overexpressed and associated with poor outcomes of CRC patients. Overexpression of HSF4 was correlated with Tumor Node Metastasis stage, and positively regulated malignant behaviors such as growth, migration, invasion of CRC cells. Moreover, miR-330-5p suppressed CRC cell growth, colony formation, migration and invasive. Interestingly, miR-330-5p recognized complementary sites within the HSF4 CDS region to reduce HSF4 expression. In rescue experiments, restoration of HSF4 expression functionally alleviated miR-330-5p-induced inhibition of cell growth, colon formation, invasion, and wound healing of CRC cells. HSF4 was associated positively with the well-known oncogenic factor MACC1 in TCGA cohort CRC samples, and knockdown of HSF4 resulted in downregulation of MACC1. In mechanism, MACC1 was suppressed upon miR-330-5p-induced downregulation of HSF4, leading to inactivation of phosphorylation of downstream STAT3. CONCLUSION: miR-330-5p suppresses tumors by directly inhibiting HSF4 to negatively modify activity of MACC1/STAT3 pathway.