Zinc finger protein 263 promotes colorectal cancer cell progression by activating STAT3 and enhancing chemoradiotherapy resistance.

Zinc finger protein 263 (ZNF263) is frequently upregulated in various tumor types; however, its function and regulatory mechanism in colorectal cancer (CRC) have not yet been elucidated. In this study, the expression of ZNF263 was systematically examined using data from The Cancer Genome Atlas database and samples from patients with CRC. The results indicated that high expression of ZNF263 in CRC tissues is significantly associated with tumor grade, lymph node metastasis and disant metastasis. Additionally, overexpression of ZNF263 significantly promoted the proliferation, invasion, migration, and epithelial-mesenchymal transition of CRC cells, while also increasing signal transducer and activator of transcription 3 (STAT3) expression and mRNA stability. Conversely, knockdown of ZNF263 inhibited the malignant behavior of CRC cells and decreased STAT3 expression and mRNA stability. Further mechanism studies using chromatin immunoprecipitation (CHIP) and luciferase assays verified that ZNF263 directly binds to the STAT3 promoter. Rescue experiments demonstrated that the knockdown or overexpression of STAT3 could significantly reverse the effects of ZNF263 on CRC cells. Additionally, our study found that overexpression of ZNF263 enhanced the resistance of CRC cells to the chemoradiotherapy. In summary, this study not only elucidated the significant role of ZNF263 in CRC but also proposed novel approaches and methodologies for the diagnosis and treatment of this malignancy.

The Atypical Dual Specificity Phosphatase DUSP15 Regulates Jak1-Mediated STAT3 Activation.

The signal transducer and activator of transcription 3 (STAT3) protein is a key regulator of cell differentiation, proliferation, and survival in hematopoiesis, immune responses, and other biological systems. STAT3 transcriptional activity is strictly regulated through various mechanisms, such as phosphorylation and dephosphorylation. In this study, we attempted to identify novel phosphatases which regulate STAT3 activity in response to cytokine stimulations. To this end, leukemia inhibitory factor (LIF)/STAT3 dependent phosphatase induction was evaluated in the mouse hepatoma cell line Hepa1-6. After LIF stimulation, the expression of several atypical dual specific phosphatases (aDUSPs) was upregulated in Hepa1-6 cells. Among the LIF-induced aDUSPs, we focused on DUSP15 and clarified its functions in LIF/STAT3 signaling using RNA interference. DUSP15 knockdown decreased LIF-induced Socs3 mRNA expression and STAT3 translocation. Furthermore, loss of DUSP15 reduced the phosphorylation of STAT3 at Tyr705 and Janus family tyrosine kinase 1 (Jak1) at Tyr1034/1035 in response to LIF. The interaction between Jak1 and DUSP15 was observed in LIF-stimulated Hepa1-6 cells. We also demonstrated the suppression of granulocyte colony-stimulating factor (G-CSF)-mediated gp130/STAT3-dependent cell growth of Ba/F-G133 cells via DUSP15 knockdown. Therefore, DUSP15 functions as a positive feedback regulator in the Jak1/STAT3 signaling cascade.

Effects of STAT4 on myocardial ischemia­reperfusion injury and the underlying mechanisms.

The regulation of cardiac function by the nuclear transcription factor signal transducer and activator of transcription 4 (STAT4) has been recently recognized. Nevertheless, the role and mechanisms of action of STAT4 in myocardial ischemia­reperfusion (I/R) injury remain unknown. Consequently, the present study constructed a rat model of I/R by ligation of the left anterior descending coronary artery. Following sacrifice, the rat hearts were excised and analyzed to investigated the effects of STAT4 on I/R­induced myocardial injury. Western blotting demonstrated that expression of STAT4 decreased significantly in the rat model of cardiac I/R and in H9C2 cells that were subjected to hypoxia and reoxygenation (H/R). The overexpression of STAT4 in H9C2 cells reduced cell damage and apoptosis induced by H/R. Furthermore, both in vivo and in vitro, the level of PI3K decreased significantly. Although the AKT protein expression levels were not altered, the AKT phosphorylation levels decreased significantly. STAT4 overexpression enhanced the expression of PI3K and AKT in the H9C2 cells. On the whole, the present study demonstrated that STAT4 alleviated I/R­induced myocardial injury through the PI3K/AKT signaling pathway.

The Mechanism of Leptin Resistance in Obesity and Therapeutic Perspective.

Leptin resistance is induced via leptin signaling blockade by chronic overstimulation of the leptin receptor and intracellular signaling defect or increased hypothalamic inflammation and suppressor of cytokine signaling (SOCS)-3 expression. High-fat diet triggers leptin resistance induced by at least two independent causes: first, the limited ability of peripheral leptin to activate hypothalamic signaling transducers and activators of transcription (STAT) signaling and secondly a signaling defect in leptin-responsive hypothalamic neurons. Central leptin resistance is dependent on decreased leptin transport efficiency across the blood brain barrier (BBB) rather than hypothalamic leptin insensitivity. Since the hypothalamic phosphorylated STAT3 (pSTAT3) represents a sensitive and specific readout of leptin receptor-B signaling, the assessment of pSTAT3 levels is the gold standard. Hypertriglyceridemia is one of important factors to inhibit the transport of leptin across BBB in obesity. Mismatch between high leptin and the amount of leptin receptor expression in obesity triggers brain leptin resistance via increasing hypothalamic inflammation and SOCS-3 expression. Therapeutic strategies that regulate the passage of leptin to the brain include the development of modifications in the structure of leptin analogues as well as the synthesis of new leptin receptor agonists with increased BBB permeability. In the hyperleptinemic state, polyethylene glycol (PEG)-modified leptin is unable to pass through the BBB. Peripheral histone deacetylase (HDAC) 6 inhibitor, tubastatin, and metformin increase central leptin sensitization. While add-on therapy with anagliptin, metformin and miglitol reduce leptin concentrations, the use of long-acting leptin analogs, and exendin-4 lead to the recovery of leptin sensitivity. Contouring surgery with fat removal, and bariatric surgery independently of the type of surgery performed provide significant improvement in leptin concentrations. Although approaches to correcting leptin resistance have shown some success, no clinically effective application has been developed to date. Due to the impairment of central and peripheral leptin signaling, as well as the extensive integration of leptin-sensitive metabolic pathways with other neurons, the effectiveness of methods used to eliminate leptin resistance is extremely limited.

IGFBP2 Functions as an Endogenous Protector against Hepatic Steatosis via Suppression of the EGFR-STAT3 Pathway.

BACKGROUND & AIMS: Non-alcoholic fatty liver disease (NAFLD) is deemed as an emerging global epidemic, whereas the underlying pathogenic mechanism remains to be clarified. We aimed to systemically analyze all the NAFLD-related gene expression datasets from published human-based studies, by which exploring potential key factors and mechanisms accounting for the pathogenesis of NAFLD. APPROACH & RESULTS: By using Robust rank aggregation method to integrate all public datasets of human NAFLD transcriptome, the present study identified IGFBP2 (Insulin-like growth factor binding protein 2) being the most significantly down-regulated gene in all NAFLD subjects. The decreased IGFBP2 expression was further confirmed in the liver tissues from patients and animal models of NAFLD. IGFBP2 deficiency aggravated hepatic steatosis and NASH phenotypes and promoted lipogenic gene expression both in vivo and in vitro. Mechanistically, IGFBP2 directly binds to and regulates EGFR, whereas blockage of the IGFBP2-EGFR complex by knockdown of IGFBP2 resulted in the EGFR-STAT3 pathway activation, which in turn promoted the promoter activity of Srebf1. By using molecular docking simulation and protein-protein interaction analysis, the sequence of 233-257 amino acids in IGFBP2 was characterized as a key motif responding for its specific binding to EGFR and the protective effect against hepatic steatosis. CONCLUSIONS: The current study has, for the first time, identified IGFBP2 as a novel protector against hepatosteatosis. The protective effect is mediated by its specific interaction with EGFR and thereby suppressing the EGFR-STAT3 pathway. Therefore, pharmaceutically targeting the IGFBP2-EGFR-STAT3 axis may provide a theoretical basis for for the treatment of NAFLD/NASH and the associated diseases.

Unraveling the unphosphorylated STAT3-unphosphorylated NF-κB pathway in loss of function STAT3 Hyper IgE syndrome.

Background: Patients with loss of function signal transducer and activator of transcription 3-related Hyper IgE Syndrome (LOF STAT3 HIES) present with recurrent staphylococcal skin and pulmonary infections along with the elevated serum IgE levels, eczematous rashes, and skeletal and facial abnormalities. Defective STAT3 signaling results in reduced Th17 cells and an impaired IL-17/IL-22 response primarily due to a compromised canonical Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway that involves STAT3 phosphorylation, dimerization, nuclear translocation, and gene transcription. The non-canonical pathway involving unphosphorylated STAT3 and its role in disease pathogenesis, however, is unexplored in HIES. Objective: This study aims to elucidate the role of unphosphorylated STAT3-unphosphorylated NF-κB (uSTAT3-uNF-κB) activation pathway in LOF STAT3 HIES patients. Methodology: The mRNA expression of downstream molecules of unphosphorylated STAT3-unphosphorylated NF-κB pathway was studied in five LOF STAT3 HIES patients and transfected STAT3 mutants post-IL-6 stimulation. Immunoprecipitation assays were performed to assess the binding of STAT3 and NF-κB to RANTES promoter. Results: A reduced expression of the downstream signaling molecules of the uSTAT3-uNF-κB complex pathway, viz., RANTES, STAT3, IL-6, IL-8, ICAM1, IL-8, ZFP36L2, CSF1, MRAS, and SOCS3, in LOF STAT3 HIES patients as well as the different STAT3 mutant plasmids was observed. Immunoprecipitation studies showed a reduced interaction of STAT3 and NF-κB to RANTES in HIES patients. Conclusion: The reduced expression of downstream signaling molecules, specially RANTES and STAT3, confirmed the impaired uSTAT3-uNF-κB pathway in STAT3 LOF HIES. Decreased levels of RANTES and STAT3 could be a significant component in the disease pathogenesis of Hyper IgE Syndrome.

IL-21 drives skin and lung inflammation and fibrosis in a model for systemic sclerosis.

BACKGROUND: Systemic sclerosis (SSc) is an autoimmune disease characterized by vasculopathy, abnormal inflammation, and fibrosis of the skin and internal organs, notably the skin and lungs, significantly impairing quality of life. There is currently no cure for SSc, and its etiology remains largely unknown, presenting a primary barrier to effective treatment. We investigated the role of interleukin-21 (IL-21) in the pathogenesis of SSc. METHODS: We assessed the expression levels of fibrosis-related genes in human dermal fibroblasts exposed to IL-21 and TGF beta. We also induced SSc in wild-type C57BL/6 mice and IL-21 knockout (KO) mice with a C57BL/6 background using bleomycin (Bleomycin). Histological analyses were conducted on skin and lung tissues from these mice. The distribution and expression levels of fibrosis-related proteins in the tissues were examined via immunohistochemistry and quantitative real-time PCR. Furthermore, we measured the frequency of Th1, Th2, and Th17 cells among splenocytes through flow cytometry. RESULTS: IL-21 activation led to STAT3 phosphorylation more than TGF beta in dermal fibroblasts. In IL-21 KO mice with BLM-induced SSc, skin thickness and lung fibrosis were reduced. The absence of IL-21 in these mice resulted in suppressed expression of fibrosis-related genes, including Col1a1, Col1a2, Col3a1, CTGF, α-SMA, STAT3, and TGFß, in the skin and lungs. It also led to a decreased frequency of Th1, Th2, and Th17 cells, as well as a lower Th17/Treg ratio among splenocytes, factors known to contribute to the development of SSc. CONCLUSIONS: IL-21 contributes to the development of SSc by promoting the expression of fibrosis-related genes and modulating the levels of CD4+ T cells.

Downregulation of CIAPIN1 regulates the proliferation, migration and glycolysis of breast cancer cells via inhibition of STAT3 pathway.

Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) is a protein that regulates apoptosis and programmed cell death. This research aims to evaluate its potential role in inhibiting breast cancer cell proliferation, migration, and glycolysis and uncover its underlying molecular mechanism. We collected breast cancer tissue samples from eight patients between January 2019 and June 2023 in our Hospital to analyse CIAPIN1 expression. We transfected human breast cancer cell lines (MCF7, MDA-MB-231, MDA-MB-453, and MDA-MB-468) with siRNA of CIAPIN1. Finally, we determined protein expression using RT-qPCR and Western blotting. CIAPIN1 expression was elevated in both breast cancer tissue and serum. Overexpression of CIAPIN1 detected in the breast cancer cell lines MCF7 and MDA-MB-468. In addition, CIAPIN1 overexpression increased cell proliferation and migration rate. CIAPIN1 downregulation suppressed cell proliferation while elevated cellular apoptosis, reactive oxygen species (ROS) production and oxidative stress in breast cancer cells. Moreover, CIAPIN1 inhibition remarkably suppressed pyruvate, lactate and adenosine triphosphate (ATP) production and reduced the pyruvate kinase M2 (PKM2) protein expression and phosphorylation of signal transducer and activator of transcription 3 (STAT3) in breast cancer cells. Downregulation of CIAPIN1 suppresses cell proliferation, migration and glycolysis capacity in breast cancer cells by inhibiting the STAT3/PKM2 pathway.

CMTM4 inhibits gastric tumorigenesis and metastasis.

Background: CKLF-like MARVEL transmembrane domain-containing 4 (CMTM4) is involved in immune regulation and tumor progression; however, its role in gastric cancer (GC) remains unclear. This study explored the role and mechanism of CMTM4 in GC. Methods: Immunohistochemistry was used to analyze CMTM4 expression in human gastric biopsied cells from patients with GC (N=23) or chronic superficial gastritis (N=23). To investigate the function of CMTM4 in GC cells, the gene CMTM4 was knocked down and overexpressed in human gastric adenocarcinoma cell line AGS. The gene CMTM4 was overexpressed in AGS cells and human gastric cell line SGC7901. Cell Counting Kit 8 (CCK-8) and cell clonogenic assays were used to analyze the proliferation of the GC cells. Flow cytometry was used to analyze the effects of CMTM4 on apoptosis and the cell cycle. Wound healing and transwell assays were used to analyze the migration and invasion of the gastric cells, respectively. The mechanism of CMTM4 in GC cells was explored using the tandem mass tags (TMTs) proteome and verified by western blot analysis. Results: CMTM4 expression was more downregulated in the human GC tissues than the gastritis tissues. CMTM4 overexpression significantly inhibited the proliferation, migration, and invasion of the GC cells, whereas CMTM4 knockdown enhanced gastric cell proliferation (P>0.05), migration (P>0.05), and invasion (P>0.05). Flow cytometry showed that CMTM4 promoted apoptosis and resulted in G1/S arrest in the GC cells. In addition, the proteome and western blot results showed that STAT1 was significantly upregulated, and the STAT1 signaling pathways were enriched in the GC cells overexpressing CMTM4. Conclusions: Our results suggest that CMTM4 plays a tumor-suppressive role in GC and may affect the growth, migration, and invasion of GC cells through the STAT1 signaling pathway. CMTM4 might have potential value as a prognosis marker and potential therapeutic target for GC therapy.

Identification of Entinostat as a Novel Modifier of STAT3 Pre-mRNA Alternative Splicing.

Signal transducer and activator of transcription 3 (STAT3) is a pleiotropic factor involved in multiple vital biological processes and a key mediator of gene transcription in response to cytokines, growth factors and aberrant activation of oncogenic signaling. STAT3 has two splicing isoforms, STAT3α and STAT3ß, derived from alternative splicing of exon 23 within pre-mRNA. STAT3ß differs from STAT3α by replacement of 55 amino-acid residues in the C-terminal transactivation domain with 7 specific amino acids. Thus, a shorter STAT3ß was originally regarded as a dominant negative isoform of STAT3α. Recently accumulating evidence from independent studies have shown STAT3 splicing isoforms confer distinct and overlapping functions in many fundamental cellular regulatory steps such as cell differentiation, inflammatory responses, and cancer progression. However, relatively little is known about the mechanisms of STAT3 pre-mRNA splicing, and it remains undiscovered which chemical compounds or bioactive substances can induce the STAT3ß expression. In this study, we generated a potent reporter for detection of alternative splicing of STAT3 pre-mRNA optimized for the screening of function-known chemical library, and successfully identified entinostat, a histone deacetylase inhibitor, as a novel inducer of STAT3ß through modulating mRNA splicing. Our findings demonstrate that alternative splicing of STAT3 can be regulated by a compound, providing an important clue for understanding the regulation mechanisms of the expression balance of STAT3 isoforms in a chemical biology approach. Entinostat is likely to be a promising seed compound for elucidating how the higher ratio of STAT3ß expression impacts on biological responses associated with Janus kinase (JAK)/STAT3 signaling pathway.

Siweixizangmaoru Decoction Ameliorated Type II Collagen-Induced Arthritis in Rats via Regulating JAK2-STAT3 and NF-κB Signaling Pathway.

Siweixizangmaoru decoction (SXD) is widely used as an anti-rheumatoid arthritis (RA) in Tibet, however, the specific anti-inflammatory mechanism of SXD is still unclear. This research attempts to examine the efficacy and possible mechanisms of SXD in treating RA. The primary chemical components of SXD were identified using UHPLC-Q-Exactive Orbitrap MS. We established a lipopolysaccharide (LPS)-induced RAW264.7 macrophage inflammatory injury model to explore the anti-inflammatory mechanism of SXD and validated it through in vivo experiments. According to our research in vitro as well as in vivo, SXD exhibits anti-inflammatory qualities. SXD can suppress nitric oxide (NO) and pro-inflammatory factor production in RAW264.7 cells activated by LPS. The mechanism underlying this effect might be connected to the janus tyrosine kinase 2-signal transducer and activator of transcription 3 (JAK2/STAT3) and nuclear factor-κB (NF-κB) signaling pathways. In vivo, SXD alleviates joint swelling, decreases the generation of inflammatory factors in the serum, lowers oxidative stress, and improves joint damage. In short, SXD improves joint degeneration and lowers symptoms associated with RA by regulating inflammation via the suppression of NF-κB and JAK2/STAT3 signaling pathway activation.

Effect of PGE2 on TT cells viability and division.

Previous studies have shown prostaglandin E2 (PGE2) produced a marked increase in calcitonin secretion in human C-cells derived from medullary thyroid carcinoma. However, it's unclear whether PGE2 can increase the growth of C cells. In this study, we use TT cells as a C cell model to investigate the effect of PGE2 on the growth of C cells. The results revealed that both PGE2 and arachidonic acid (AA) significantly increased the count of TT cells, whereas indomethacin and Dup697 reduced this count. Notably, an increase in the level of AA was associated with an increase in the number of proliferating TT cells, indicating a dose-response relationship. PGE2 and its receptor agonists (sulprostone and butaprost) enhanced the proliferation of TT cells. By contrast, 17-phenyl-trinor-PGE2 exerted no significant effect on TT cell proliferation, whereas L161982 suppressed it. The positive effect of AA on TT cell proliferation was inhibited by indomethacin, NS398, Dup697 (complete inhibition), and SC560. Both PGE2 and AA increased the level of p-STAT5a. The positive effect of AA on p-STAT5a was completely inhibited by Dup697 but not indomethacin, NS398, or SC560. Treatment with indomethacin or Dup697 alone reduced the level of STAT5a in TT cells. AA increased the level of STAT5a, but this effect was inhibited by indomethacin, NS398, and Dup697. Overall, this study confirms the effect of PGE2 on the proliferation of TT cells. This effect is likely mediated through EP2, EP3, and EP4 receptors and associated with an increase in p-STAT5a level within TT cells.

T-cell Large Granular Lymphocytic Leukemia with a STAT3 mutation successfully treated with Cord Blood Transplantation.

A 64-year-old woman presented with agranulocytosis, anemia, and bacteremia, leading to a diagnosis of T-cell large granular lymphocytic leukemia (T-LGLL). A molecular analysis identified a signal transducer and activator of transcription 3 (STAT3) Y640F variant. Initial treatment with cyclophosphamide and prednisolone did not improve her condition, but serious infections were observed. The patient underwent cord blood transplantation (CBT) after preconditioning with fludarabine, busulfan, and total body irradiation, yielding a STAT3 Y640F variant disappearance, based on allele-specific quantitative polymerase chain reaction (AS-qPCR). In this case, CBT is a promising refractory T-LGLL treatment option, and the STAT3 Y640F variant AS-qPCR is a T-LGLL activity marker.

T-cell large granular lymphocytic leukemia with a STAT3 mutation successfully treated with cord blood transplantation.

A 64-year-old woman presented with agranulocytosis, anemia, and bacteremia, leading to a diagnosis of T-cell large granular lymphocytic leukemia (T-LGLL). A molecular analysis identified a signal transducer and activator of transcription 3 (STAT3) Y640F variant. Initial treatment with cyclophosphamide and prednisolone did not improve her condition, but serious infections were observed. The patient underwent cord blood transplantation (CBT) after preconditioning with fludarabine, busulfan, and total body irradiation, yielding a STAT3 Y640F variant disappearance, based on allele-specific quantitative polymerase chain reaction (AS-qPCR). In this case, CBT is a promising refractory T-LGLL treatment option, and the STAT3 Y640F variant AS-qPCR is a T-LGLL activity marker.

TTI-101 targets STAT3/c-Myc signaling pathway to suppress cervical cancer progression: an integrated experimental and computational analysis.

BACKGROUND: Cervical cancer (CC) is a significant global health concern, demanding the consideration of novel therapeutic strategies. The signal transducer and activator of transcription 3 (STAT3) pathway has been implicated in cancer progression and is a potential target for therapeutic intervention. This study aimed to explore the therapeutic potential of TTI-101, a small molecule STAT3 inhibitor, in CC and investigate its underlying mechanisms. METHODS: Molecular docking studies and molecular dynamics simulations were performed to explore the binding interaction between TTI-101 and STAT3 and assess the stability of the STAT3-TTI-101 complex. Cell viability assays, wound healing assays, colony formation assays, flow cytometry analysis, and gene expression analysis were conducted. In vivo xenograft models were used to assess the antitumor efficacy of TTI-101. RESULTS: The in silico analysis shows a stable binding interaction between TTI-101 and STAT3. TTI-101 treatment inhibits cell viability, clonogenic ability, and cell migration in CC cells. Furthermore, TTI-101 induces apoptosis and cell cycle arrest. Analysis of apoptosis-related markers demonstrated dysregulation of Bax, Bcl-2, and Caspase-3 upon TTI-101 treatment. Moreover, TTI-101 caused G2/M phase arrest accompanied by a decrease in CDK1 and Cyclin B1 at mRNA levels. In the xenograft model, TTI-101 significantly inhibited tumor growth without adverse effects on body weight. CONCLUSION: TTI-101 exhibited anticancer effects by targeting the STAT3/c-Myc signaling pathway, inducing cell cycle arrest, and promoting apoptosis in CC cells. These findings provide valuable insights into the development of novel therapeutic strategies for cervical cancer. Further investigation is warranted to validate the clinical application of TTI-101.

Ferulic acid inhibits tumor proliferation and attenuates inflammation of hepatic tissues in experimentally induced HCC in rats.

Hepatocellular carcinoma (HCC) is a prevalent form of primary liver cancer with a 5-year survival rate of just 18%. Ferulic acid, a natural compound found in fruits and vegetables such as sweet corn, rice bran, and dong quai, is an encouraging drug known for its diverse positive effects on the body, including anti-inflammatory, anti-apoptotic, and neuroprotective properties. Our study aimed to investigate the potential antitumor effects of ferulic acid to inhibit tumor growth and inflammation of HCC in rats. HCC was induced in rats by administering thioacetamide. Additionally, some rats were given 50 mg/kg of ferulic acid three times a week for 16 weeks. Liver function was assessed by measuring serum alpha-fetoprotein (AFP) and examining hepatic tissue sections stained with hematoxylin/eosin or anti-hypoxia induced factor-1α (HIF-1α). The hepatic mRNA and protein levels of HIF-1α, nuclear factor κB (NFκB), tumor necrosis factor-α (TNF-α), mammalian target of rapamycin (mTOR), signal transducer and activator of transcription 3 (STAT3), cMyc, and cyclin D1 were examined. The results showed that ferulic acid increased the rats' survival rate by reducing serum AFP levels and suppressing hepatic nodules. Furthermore, ferulic acid ameliorated the appearance of vacuolated cytoplasm induced by HCC, reduced apoptotic nuclei, and necrotic nodules. Finally, ferulic acid decreased the expression of HIF-1α, NFκB, TNF-α, mTOR, STAT3, cMyc, and cyclin D1. In conclusion, ferulic acid is believed to possess antitumor properties by inhibiting HCC-induced hypoxia through the suppression of HIF-1α expression. Additionally, it helps in reducing the expression of mTOR, STAT3, cMyc, and cyclin D1, thereby slowing down tumor growth. Lastly, ferulic acid reduced hepatic tissue inflammation by downregulating NFκB and TNF-α.

Therapeutic Effects of Arctiin on Alzheimer's Disease-like Model in Rats by Reducing Oxidative Stress, Inflammasomes and Fibrosis.

BACKGROUND: Alzheimer's disease (AD) affects approximately 50 million people globally and is expected to triple by 2050. Arctiin is a lignan found in the Arctium lappa L. plant. Arctiin possesses anti-proliferative, antioxidative and anti-adipogenic. OBJECTIVES: We aimed to explore the potential therapeutic effects of Arctiin on rats with AD by evaluating the expression of TLR4, NLRP3, STAT3, TGF-ß, cyclin D1, and CDK2. METHODS: AD was induced in rats by administering 70 mg/kg of aluminum chloride through intraperitoneal injection daily for six weeks. After inducing AD, some rats were treated with 25 mg/kg of Arctiin daily for three weeks through oral gavage. Furthermore, to examine the brain tissue structure, hippocampal sections were stained with hematoxylin/eosin and anti-TLR4 antibodies. The collected samples were analyzed for gene expression and protein levels of TLR4, NLRP3, STAT3, TGF-ß, cyclin D1, and CDK2. RESULTS: In behavioral tests, rats showed a significant improvement in their behavior when treated with Arctiin. Microimages stained with hematoxylin/eosin showed that Arctiin helped to improve the structure and cohesion of the hippocampus, which was previously impaired by AD. Furthermore, Arctiin reduced the expression of TLR4, NLRP3, STAT3, TGF-ß, cyclin D1, and CDK2. CONCLUSION: Arctiin can enhance rats' behavior and structure of the hippocampus in AD rats. This is achieved through its ability to reduce the expression of both TLR4 and NLRP3, hence inhibiting the inflammasome pathway. Furthermore, Arctiin can improve tissue fibrosis by regulating STAT3 and TGF-ß. Lastly, it can block the cell cycle proteins cyclin D1 and CDK2.

Evaluating the specific STAT3 inhibitor YHO-1701 in ovarian cancer cell lines and patient-derived cell models: efficacy, mechanisms, and therapeutic potential.

OBJECTIVE: Signal transducer and activator of transcription 3 (STAT3) plays key roles in regulating cancer cell proliferation, survival, and metastasis. We aimed to determine the effects of YHO-1701, an oral STAT3 inhibitor, in ovarian cancer (OC). METHODS: We evaluated the impact of YHO-1701 on cell growth in patient-derived cells (PDCs) and OC cell lines using standard cell proliferation assays. Spheroid models derived from PDCs were assessed using three-dimensional (3D) cell viability assays. Antitumor activity was performed in SKOV3 xenograft mice treated orally administrated YHO-1701 with 20 mg/kg. Changes in STAT3 signaling were analyzed by western blotting. The molecular mechanisms of STAT3 inhibition were investigated by sequencing RNA and analyzing pathways in the SKOV3 using a small interfering RNA targeting STAT3 (STAT3 siRNA) and YHO-1701. RESULTS: YHO-1701 inhibited the growth of OC cell lines by preventing STAT3 dimerization and decreasing the expression of its downstream signaling molecule, survivin. The growth of PDCs and spheroids obtained from patients with primary and recurrent OCs was significantly inhibited. Antitumor effect was observed in the SKOV3 xenograft mice with YHO-1701. YHO-1701 induced apoptosis in OC cells. Additionally, p53 and/or MAPK signaling pathways were upregulated in SKOV3 cells incubated with YHO-1701 and in those with STAT3 siRNA. CONCLUSION: Our results showed that YHO-1701 suppressed cell growth in PDCs of OC, accompanied by survivin inhibition, and a decrease in the number of peritoneal metastasis in the mice by YHO-1701, compared with those treated with control. Therefore, YHO-1701 could be a promising candidate agent for treating OC.

Construction and validation of a synthetic phage-displayed nanobody library.

Nanobodies derived from camelids and sharks offer unique advantages in therapeutic applications due to their ability to bind to epitopes that were previously inaccessible. Traditional methods of nanobody development face challenges such as ethical concerns and antigen toxicity. Our study presents a synthetic, phagedisplayed nanobody library using trinucleotide-directed mutagenesis technology, which allows precise amino acid composition in complementarity-determining regions (CDRs), with a focus on CDR3 diversity. This approach avoids common problems such as frameshift mutations and stop codon insertions associated with other synthetic antibody library construction methods. By analyzing FDA-approved nanobodies and Protein Data Bank sequences, we designed sub-libraries with different CDR3 lengths and introduced amino acid substitutions to improve solubility. The validation of our library through the successful isolation of nanobodies against targets such as PD-1, ATXN1 and STAT3 demonstrates a versatile and ethical platform for the development of high specificity and affinity nanobodies and represents a significant advance in biotechnology.

Identification and mechanistic exploration of key anti-inflammatory molecules in American ginseng: Impacts on signal transducer and activator of transcription 3 STAT3 phosphorylation and macrophage polarization.

American ginseng (AG) has been reported to have anti-inflammatory effects in many diseases, but the key molecules and mechanisms are unclear. This study aims to evaluate the anti-inflammatory mechanism of AG and identify the key molecules by in vivo and in vitro models. Zebrafish was employed to assess the anti-inflammatory properties of AG and the compounds. Metabolomics was utilized to identify potential anti-inflammatory molecules in AG, while molecular dynamics simulations were conducted to forecast the interaction capabilities of these compounds with inflammatory targets. Additionally, macrophage cell was employed to investigate the anti-inflammatory mechanisms of the key molecules in AG by enzyme-linked immunosorbent assay and western blotting. Seven potential anti-inflammatory molecules were discovered in AG, with ginsenoside Rg1, ginsenoside Rs3 (G-Rs3), and oleanolic acid exhibiting the strongest affinity for signal transducer and activator of transcription 3. These compounds demonstrated inhibitory effects on macrophage migration in zebrafish models and the ability to regulate ROS levels in both zebrafish and macrophages. The cell experiments found that ginsenoside Rg1, ginsenoside Rs3, and oleanolic acid could promote macrophage M2/M1 polarization ratio and inhibit phosphorylation overexpression of signal transducer and activator of transcription 3. This study revealed the key anti-inflammatory molecules and mechanisms of AG, and provided new evidence of anti-inflammatory for the scientific use of AG.