Diverse roles of SARS-CoV-2 Spike and Nucleocapsid proteins in EndMT stimulation through the TGF-ß-MRTF axis inhibited by aspirin.

BACKGROUND: The SARS-CoV-2 virus causes severe COVID-19 in one-fifth of patients. In addition to high mortality, infection may induce respiratory failure and cardiovascular complications associated with inflammation. Acute or prolonged inflammation results in organ fibrosis, the cause of which might be endothelial disorders arising during the endothelial-mesenchymal transition (EndMT). METHODS: HUVECs and HMEC-1 cells were stimulated with SARS-CoV-2 S (Spike) and N (Nucleocapsid) proteins, and EndMT induction was evaluated by studying specific protein markers via Western blotting. Wound healing and tube formation assays were employed to assess the potential of SARS-CoV-2 to stimulate changes in cell behaviour. MRTF nuclear translocation, ROS generation, TLR4 inhibitors, TGF-ß-neutralizing antibodies, and inhibitors of the TGF-ß-dependent pathway were used to investigate the role of the TGF-ß-MRTF signalling axis in SARS-CoV-2-dependent EndMT stimulation. RESULTS: Both viral proteins stimulate myofibroblast trans-differentiation. However, the N protein is more effective at EndMT induction. The TGF-ß-MRTF pathway plays a critical role in this process. The N protein preferentially favours action through TGF-ß2, whose secretion is induced through TLR4-ROS action. TGF-ß2 stimulates MRTF-A and MRTF-B nuclear translocation and strongly regulates EndMT. In contrast, the Spike protein stimulates TGF-ß1 secretion as a result of ACE2 downregulation. TGF-ß1 induces only MRTF-B, which, in turn, weakly regulates EndMT. Furthermore, aspirin, a common nonsteroidal anti-inflammatory drug, might prevent and reverse SARS-CoV-2-dependent EndMT induction through TGF-ß-MRTF pathway deregulation. CONCLUSION: The reported study revealed that SARS-CoV-2 infection induces EndMT. Moreover, it was demonstrated for the first time at the molecular level that the intensity of the EndMT triggered by SARS-CoV-2 infection may vary and depend on the viral protein involved. The N protein acts through TLR4-ROS-TGF-ß2-MRTF-A/B, whereas the S protein acts through ACE2-TGF-ß1-MRTF-B. Furthermore, we identified aspirin as a potential anti-fibrotic drug for treating patients with SARS-CoV-2 infection.

Astragaloside IV alleviates renal fibrosis by inhibiting renal tubular epithelial cell pyroptosis induced by urotensin II through regulating the cAMP/PKA signaling pathway.

OBJECTIVE: To explore the molecular mechanism of Astragaloside IV (AS-IV) in alleviating renal fibrosis by inhibiting Urotensin II-induced pyroptosis and epithelial-mesenchymal transition of renal tubular epithelial cells. METHODS: Forty SD rats were randomly divided into control group without operation: gavage with 5ml/kg/d water for injection and UUO model group: gavage with 5ml/kg/d water for injection; UUO+ AS-IV group (gavage with AS-IV 20mg/kg/d; and UUO+ losartan potassium group (gavage with losartan potassium 10.3mg/kg/d, with 10 rats in each group. After 2 weeks, Kidney pathology, serum Urotensin II, and cAMP concentration were detected, and the expressions of NLRP3, GSDMD-N, Caspase-1, and IL-1ß were detected by immunohistochemistry. Rat renal tubular epithelial cells were cultured in vitro, and different concentrations of Urotensin II were used to intervene for 24h and 48h. Cell proliferation activity was detected using the CCK8 assay. Suitable concentrations of Urotensin II and intervention time were selected, and Urotensin II receptor antagonist (SB-611812), inhibitor of PKA(H-89), and AS-IV (15ug/ml) were simultaneously administered. After 24 hours, cells and cell supernatants from each group were collected. The cAMP concentration was detected using the ELISA kit, and the expression of PKA, α-SMA, FN, IL-1ß, NLRP3, GSDMD-N, and Caspase-1 was detected using cell immunofluorescence, Western blotting, and RT-PCR. RESULTS: Renal tissue of UUO rats showed renal interstitial infiltration, tubule dilation and atrophy, renal interstitial collagen fiber hyperplasia, and serum Urotensin II and cAMP concentrations were significantly higher than those in the sham operation group (p <0.05). AS-IV and losartan potassium intervention could alleviate renal pathological changes, and decrease serum Urotensin II, cAMP concentration levels, and the expressions of NLRP3, GSDMD-N, Caspase-1, and IL-1ß in renal tissues (p <0.05). Urotensin II at a concentration of 10-8 mol/L could lead to the decrease of cell proliferation, (p<0.05). Compared with the normal group, the cAMP level and the PKA expression were significantly increased (p<0.05). After intervention with AS-IV and Urotensin II receptor antagonist, the cAMP level and the expression of PKA were remarkably decreased (p<0.05). Compared with the normal group, the expression of IL-1ß, NLRP3, GSDMD-N, and Caspase-1 in the Urotensin II group was increased (p<0.05), which decreased in the AS-IV and H-89 groups. CONCLUSION: AS-IV can alleviate renal fibrosis by inhibiting Urotensin II-induced pyroptosis of renal tubular epithelial cells by regulating the cAMP/PKA signaling pathway.

Nanocarrier - Mediated Salinomycin Delivery Induces Apoptosis and Alters EMT Phenomenon in Prostate Adenocarcinoma.

Salinomycin (Sal) has been recently discovered as a novel chemotherapeutic agent against various cancers including prostate cancer which is one of the most commonly diagnosed cancers affecting male populations worldwide. Herein we designed salinomycin nanocarrier (Sal-NPs) to extend its systemic circulation and to increase its anticancer potential. Prepared nanoform showed high encapsulation and sustained release profile for salinomycin. The present study elucidated the cytotoxicity and mechanism of apoptotic cell death of Sal-NPs against prostate cancer both in vitro and in vivo. At all measured concentrations, Sal-NPs showed more significant cytotoxicity to DU145 and PC3 cells than Sal alone. This effect was mediated by apoptosis, as confirmed by ROS generation, loss of MMP and cell cycle arrest at the G1 phase in both cells. Sal-NPs efficiently inhibited migration of PC3 and DU145 cells via effectively downregulating the epithelial mesenchymal transition. Also, the results confirmed that Sal-NPs can effectively inhibit the induction of Prostate adenocarcinoma in male Wistar rats. Sal-NPs treatment exhibited a decrease in tumour sizes, a reduction in prostate weight, and an increase in body weight, which suggests that Sal-NPs is more effective than salinomycin alone. Our results suggest that the molecular mechanism underlying the Sal-NPs anticancer effect may lead to the development of a potential therapeutic strategy for treating prostate adenocarcinoma.

Regulation of cellular and molecular markers of epithelial-mesenchymal transition by Brazilin in breast cancer cells.

Breast cancer is the most common invasive neoplasm and the leading cause of cancer death in women worldwide. The main cause of mortality in cancer patients is invasion and metastasis, where the epithelial-mesenchymal transition (EMT) is a crucial player in these processes. Pharmacological therapy has plants as its primary source, including isoflavonoids. Brazilin is an isoflavonoid isolated from Haematoxilum brasiletto that has shown antiproliferative activity in several cancer cell lines. In this study, we evaluated the effect of Brazilin on canonical markers of EMT such as E-cadherin, vimentin, Twist, and matrix metalloproteases (MMPs). By Western blot, we evaluated E-cadherin, vimentin, and Twist expression and the subcellular localization by immunofluorescence. Using gelatin zymography, we determined the levels of secretion of MMPs. We used Transwell chambers coated with matrigel to determine the in vitro invasion of breast cancer cells treated with Brazilin. Interestingly, our results show that Brazilin increases 50% in E-cadherin expression and decreases 50% in vimentin and Twist expression, MMPs, and cell invasion in triple-negative breast cancer (TNBC) MDA-MB-231 and to a lesser extend in MCF7 ER+ breast cancer cells. Together, these findings position Brazilin as a new molecule with great potential for use as complementary or alternative treatment in breast cancer therapy in the future.

DNA-PKcs/AKT1 inhibits epithelial-mesenchymal transition during radiation-induced pulmonary fibrosis by inducing ubiquitination and degradation of Twist1.

INTRODUCTION: Radiation-induced pulmonary fibrosis (RIPF) is a chronic, progressive, irreversible lung interstitial disease that develops after radiotherapy. Although several previous studies have focused on the mechanism of epithelial-mesenchymal transition (EMT) in lung epithelial cells, the essential factors involved in this process remain poorly understood. The DNA-dependent protein kinase catalytic subunit (DNA-PKcs) exhibits strong repair capacity when cells undergo radiation-induced damage; whether DNA-PKcs regulates EMT during RIPF remains unclear. OBJECTIVES: To investigate the role and molecular mechanism of DNA-PKcs in RIPF and provide an important theoretical basis for utilising DNA-PKcs-targeted drugs for preventing RIPF. METHODS: DNA-PKcs knockout (DPK-/-) mice were generated via the Cas9/sgRNA technique and subjected to whole chest ionizing radiation (IR) at a 20 Gy dose. Before whole chest IR, the mice were intragastrically administered the DNA-PKcs-targeted drug VND3207. Lung tissues were collected at 1 and 5 months after IR. RESULTS: The expression of DNA-PKcs is low in pulmonary fibrosis (PF) patients. DNA-PKcs deficiency significantly exacerbated RIPF by promoting EMT in lung epithelial cells. Mechanistically, DNA-PKcs deletion by shRNA or inhibitor NU7441 maintained the protein stability of Twist1. Furthermore, AKT1 mediated the interaction between DNA-PKcs and Twist1. High Twist1 expression and EMT-associated changes caused by DNA-PKcs deletion were blocked by insulin-like growth factor-1 (IGF-1), an AKT1 agonist. The radioprotective drug VND3207 prevented IR-induced EMT and alleviated RIPF in mice by stimulating the kinase activity of DNA-PKcs. CONCLUSION: Our study clarified the critical role and mechanism of DNA-PKcs in RIPF and showed that it could be a potential target for preventing RIPF.

Melatonin alleviates myocardial dysfunction through inhibition of endothelial-to-mesenchymal transition via the NF-κB pathway.

Endothelial-to-mesenchymal transition (EndMT) is a complex biological process of cellular transdifferentiation by which endothelial cells (ECs) lose their characteristics and acquire mesenchymal properties, leading to cardiovascular remodeling and complications in the adult cardiovascular diseases environment. Melatonin is involved in numerous physiological and pathological processes, including aging, and has anti-inflammatory and antioxidant activities. This molecule is an effective therapeutic candidate for preventing oxidative stress, regulating endothelial function, and maintaining the EndMT balance to provide cardiovascular protection. Although recent studies have documented improved cardiac function by melatonin, the mechanism of action of melatonin on EndMT remains unclear. The present study investigated the effects of melatonin on induced EndMT by transforming growth factor-ß2/interleukin-1ß in both in vivo and in vitro models. The results revealed that melatonin reduced the migratory ability and reactive oxygen species levels of the cells and ameliorated mitochondrial dysfunction in vitro. Our findings indicate that melatonin prevents endothelial dysfunction and inhibits EndMT by activating related pathways, including nuclear factor kappa B and Smad. We also demonstrated that this molecule plays a crucial role in restoring cardiac function by regulating the EndMT process in the ischemic myocardial condition, both in vessel organoids and myocardial infarction (MI) animal models. In conclusion, melatonin is a promising agent that attenuates EC dysfunction and ameliorates cardiac damage compromising the EndMT process after MI.

Targeting EMT using low-dose Teniposide by downregulating ZEB2-driven activation of RNA polymerase I in breast cancer.

Metastatic dissemination from the primary tumor is a complex process that requires crosstalk between tumor cells and the surrounding milieu and involves the interplay between numerous cellular-signaling programs. Epithelial-mesenchymal transition (EMT) remains at the forefront of orchestrating a shift in numerous cellular programs, such as stemness, drug resistance, and apoptosis that allow for successful metastasis. Till date, there is limited success in therapeutically targeting EMT. Utilizing a high throughput screen of FDA-approved compounds, we uncovered a novel role of the topoisomerase inhibitor, Teniposide, in reversing EMT. Here, we demonstrate Teniposide as a potent modulator of the EMT program, specifically through an IRF7-NMI mediated response. Furthermore, Teniposide significantly reduces the expression of the key EMT transcriptional regulator, Zinc Finger E-Box Binding Homeobox 2 (ZEB2). ZEB2 downregulation by Teniposide inhibited RNA polymerase I (Pol I) activity and rRNA biogenesis. Importantly, Teniposide treatment markedly reduced pulmonary colonization of breast cancer cells. We have uncovered a novel role of Teniposide, which when used at a very low concentration, mitigates mesenchymal-like invasive phenotype. Overall, its ability to target EMT and rRNA biogenesis makes Teniposide a viable candidate to be repurposed as a therapeutic option to restrict breast cancer metastases.

Simvastatin attenuates silica-induced pulmonary inflammation and fibrosis in rats via the AMPK-NOX pathway.

BACKGROUND: Simvastatin (Sim), a hydroxy-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor, has been widely used in prevention and treatment of cardiovascular diseases. Studies have suggested that Sim exerts anti-fibrotic effects by interfering fibroblast proliferation and collagen synthesis. This study was to determine whether Sim could alleviate silica-induced pulmonary fibrosis and explore the underlying mechanisms. METHODS: The rat model of silicosis was established by the tracheal perfusion method and treated with Sim (5 or 10 mg/kg), AICAR (an AMPK agonist), and apocynin (a NOX inhibitor) for 28 days. Lung tissues were collected for further analyses including pathological histology, inflammatory response, oxidative stress, epithelial mesenchymal transformation (EMT), and the AMPK-NOX pathway. RESULTS: Sim significantly reduced silica-induced pulmonary inflammation and fibrosis at 28 days after administration. Sim could reduce the levels of interleukin (IL)-1ß, IL-6, tumor necrosis factor-α and transforming growth factor-ß1 in lung tissues. The expressions of hydroxyproline, α-SMA and vimentin were down-regulated, while E-cad was increased in Sim-treated rats. In addition, NOX4, p22pox, p40phox, p-p47phox/p47phox expressions and ROS levels were all increased, whereas p-AMPK/AMPK was decreased in silica-induced rats. Sim or AICAR treatment could notably reverse the decrease of AMPK activity and increase of NOX activity induced by silica. Apocynin treatment exhibited similar protective effects to Sim, including down-regulating of oxidative stress and inhibition of the EMT process and inflammatory reactions. CONCLUSIONS: Sim attenuates silica-induced pulmonary inflammation and fibrosis by downregulating EMT and oxidative stress through the AMPK-NOX pathway.

Tabersonine enhances cisplatin sensitivity by modulating Aurora kinase A and suppressing epithelial-mesenchymal transition in triple-negative breast cancer.

CONTEXT: Tabersonine has been investigated for its role in modulating inflammation-associated pathways in various diseases. However, its regulatory effects on triple-negative breast cancer (TNBC) have not yet been fully elucidated. OBJECTIVE: This study uncovers the anticancer properties of tabersonine in TNBC cells, elucidating its role in enhancing chemosensitivity to cisplatin (CDDP). MATERIALS AND METHODS: After tabersonine (10 µM) and/or CDDP (10 µM) treatment for 48 h in BT549 and MDA-MB-231 cells, cell proliferation was evaluated using the cell counting kit-8 and colony formation assays. Quantitative proteomics, online prediction tools and molecular docking analyses were used to identify potential downstream targets of tabersonine. Transwell and wound-healing assays and Western blot analysis were used to assess epithelial-mesenchymal transition (EMT) phenotypes. RESULTS: Tabersonine demonstrated inhibitory effects on TNBC cells, with IC50 values at 48 h being 18.1 µM for BT549 and 27.0 µM for MDA-MB-231. The combined treatment of CDDP and tabersonine synergistically suppressed cell proliferation in BT549 and MDA-MB-231 cells. Enrichment analysis revealed that the proteins differentially regulated by tabersonine were involved in EMT-related signalling pathways. This combination treatment also effectively restricted EMT-related phenotypes. Through the integration of online target prediction and proteomic analysis, Aurora kinase A (AURKA) was identified as a potential downstream target of tabersonine. AURKA expression was reduced in TNBC cells post-treatment with tabersonine. DISCUSSION AND CONCLUSIONS: Tabersonine significantly enhances the chemosensitivity of CDDP in TNBC cells, underscoring its potential as a promising therapeutic agent for TNBC treatment.

Scopoletin alleviates high glucose-induced toxicity in human renal proximal tubular cells via inhibition of oxidative damage, epithelial-mesenchymal transition, and fibrogenesis.

BACKGROUND: Recent years of evidence suggest the crucial role of renal tubular cells in developing diabetic kidney disease. Scopoletin (SCOP) is a plant-based coumarin with numerous biological activities. This study aimed to determine the effect of SCOP on renal tubular cells in developing diabetic kidney disease and to elucidate mechanisms. METHODS AND RESULTS: In this study, SCOP was evaluated in vitro using renal proximal tubular (HK-2) cells under hyperglycemic conditions to understand its mechanism of action. In HK-2 cells, SCOP alleviated the high glucose-generated reactive oxygen species (ROS), restored the levels of reduced glutathione, and decreased lipid peroxidation. High glucose-induced alteration in the mitochondrial membrane potential was markedly restored in the SCOP-treated cells. Moreover, SCOP significantly reduced the high glucose-induced apoptotic cell population in the Annexin V-FITC flow cytometry study. Furthermore, high glucose markedly elevated the mRNA expression of fibrotic and extracellular matrix (ECM) components, namely, transforming growth factor (TGF)-ß, alfa-smooth muscle actin (α-SMA), collagen I, and collagen III, in HK-2 cells compared to the untreated cells. SCOP treatment reduced these mRNA expressions compared to the high glucose-treated cells. Collagen I and TGF-ß protein levels were also significantly reduced in the SCOP-treated cells. Further findings in HK-2 cells revealed that SCOP interfered with the epithelial-mesenchymal transition (EMT) in the high glucose-treated HK-2 cells by normalizing E-cadherin and downregulating the vimentin and α-SMA proteins. CONCLUSIONS: In conclusion, SCOP modulates the high glucose-generated renal tubular cell oxidative damage and accumulation of ECM components and may be a promising molecule against diabetic nephropathy.

ULK1 Mediated Autophagy-Promoting Effects of Rutin-Loaded Chitosan Nanoparticles Contribute to the Activation of NF-κB Signaling Besides Inhibiting EMT in Hep3B Hepatoma Cells.

Background: Liver cancer remains to be one of the leading causes of cancer worldwide. The treatment options face several challenges and nanomaterials have proven to improve the bioavailability of several drug candidates and their applications in nanomedicine. Specifically, chitosan nanoparticles (CNPs) are extremely biodegradable, pose enhanced biocompatibility and are considered safe for use in medicine. Methods: CNPs were synthesized by ionic gelation, loaded with rutin (rCNPs) and characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and transmission electron microscopy (TEM). The rCNPs were tested for their cytotoxic effects on human hepatoma Hep3B cells, and experiments were conducted to determine the mechanism of such effects. Further, the biocompatibility of the rCNPs was tested on L929 fibroblasts, and their hemocompatibility was determined. Results: Initially, UV-vis and FTIR analyses indicated the possible loading of rutin on rCNPs. Further, the rutin load was quantitatively measured using Ultra-Performance Liquid Chromatography (UPLC) and the concentration was 88 µg/mL for 0.22 micron filtered rCNPs. The drug loading capacity (LC%) of the rCNPs was observed to be 13.29 ± 0.68%, and encapsulation efficiency (EE%) was 19.55 ± 1.01%. The drug release was pH-responsive as 88.58% of the drug was released after 24 hrs at the lysosomal pH 5.5, whereas 91.44% of the drug was released at physiological pH 7.4 after 102 hrs. The cytotoxic effects were prominent in 0.22 micron filtered samples of 5 mg/mL rutin precursor. The particle size for the rCNPs at this concentration was 144.1 nm and the polydispersity index (PDI) was 0.244, which is deemed to be ideal for tumor targeting. A zeta potential (ζ-potential) value of 16.4 mV indicated rCNPs with good stability. The IC50 value for the cytotoxic effects of rCNPs on human hepatoma Hep3B cells was 9.7 ± 0.19 µg/mL of rutin load. In addition, the increased production of reactive oxygen species (ROS) and changes in mitochondrial membrane potential (MMP) were observed. Gene expression studies indicated that the mechanism for cytotoxic effects of rCNPs on Hep3B cells was due to the activation of Unc-51-like autophagy-activating kinase (ULK1) mediated autophagy and nuclear factor kappa B (NF-κB) signaling besides inhibiting the epithelial-mesenchymal Transition (EMT). In addition, the rCNPs were less toxic on NCTC clone 929 (L929) fibroblasts in comparison to the Hep3B cells and possessed excellent hemocompatibility (less than 2% of hemolysis). Conclusion: The synthesized rCNPs were pH-responsive and possessed the physicochemical properties suitable for tumor targeting. The particles were effectively cytotoxic on Hep3B cells in comparison to normal cells and possessed excellent hemocompatibility. The very low hemolytic profile of rCNPs indicates that the drug could be administered intravenously for cancer therapy.

Paeoniflorigenone inhibits ovarian cancer metastasis through targeting the MUC1/Wnt/ß­catenin pathway.

Ovarian cancer (OC) is one of the most common gynecological malignancies. Currently, chemoradiotherapy is the primary clinical treatment approach for OC; however, it has severe side effects and a high rate of recurrence. Thus, there is an urgent need to develop innovative therapeutic options. Paeoniflorigenone (PFG) is a monoterpene compound isolated from the traditional Chinese medicine Paeoniae Radix Rubra. PFG can inhibit the proliferation of tumor cells; however, its anticancer activity against OC has yet to be elucidated. Mucin 1 (MUC1) is highly expressed in various malignant tumors, and is associated with tumor proliferation, metastasis and epithelial­mesenchymal transition (EMT). In addition, MUC1 affects numerous signaling pathways in tumor cells. In order to develop a possible treatment approach for metastatic OC, the antitumor activity of PFG in OC cells was investigated using Cell Counting Kit­8 assay, Edu assay, flow cytometry, Transwell assay and western blot analysis. In addition, it was assessed how PFG affects MUC1 expression and function. The experiments revealed that PFG significantly inhibited OC cell proliferation, migration, invasion and EMT. PFG also induced S­phase cell cycle arrest in OC cells. Furthermore, PFG inhibited MUC1 promoter activity, which led to a decrease in MUC1 protein expression. By contrast, MUC1 promoted OC progression, including cell proliferation, cell cycle progression and cell migration. Stable knockdown of MUC1 in OC cells improved the ability of PFG to block the Wnt/ß­catenin pathway, and to limit tumor cell invasion and migration, whereas MUC1 overexpression partially counteracted the antitumor effects of PFG. In conclusion, the present study demonstrated that PFG may inhibit the MUC1/Wnt/ß­catenin pathway to induce anti­metastatic, anti­invasive and anti­EMT effects on OC. Notably, MUC1 may be a direct target of PFG. Thus, PFG holds promise as a specific antitumor agent for the treatment of OC.

Exosomes derived from adipose tissue-derived stem cells alleviated H2O2-induced oxidative stress and endothelial-to-mesenchymal transition in human umbilical vein endothelial cells by inhibition of the mir-486-3p/Sirt6/Smad signaling pathway.

Hypertrophic scar (HS) is characterized by excessive collagen deposition and myofibroblasts activation. Endothelial-to-mesenchymal transition (EndoMT) and oxidative stress were pivotal in skin fibrosis process. Exosomes derived from adipose tissue-derived stem cells (ADSC-Exo) have the potential to attenuate EndoMT and inhibit fibrosis. The study revealed reactive oxygen species (ROS) levels were increased during EndoMT occurrence of dermal vasculature of HS. The morphology of endothelial cells exposure to H2O2, serving as an in vitro model of oxidative stress damage, transitioned from a cobblestone-like appearance to a spindle-like shape. Additionally, the levels of endothelial markers decreased in H2O2-treated endothelial cell, while the expression of fibrotic markers increased. Furthermore, H2O2 facilitated the accumulation of ROS, inhibited cell proliferation, retarded its migration and suppressed tube formation in endothelial cell. However, ADSC-Exo counteracted the biological effects induced by H2O2. Subsequently, miRNAs sequencing analysis revealed the significance of mir-486-3p in endothelial cell exposed to H2O2 and ADSC-Exo. Mir-486-3p overexpression enhanced the acceleration of EndoMT, its inhibitors represented the attenuation of EndoMT. Meanwhile, the target regulatory relationship was observed between mir-486-3p and Sirt6, whereby Sirt6 exerted its anti-EndoMT effect through Smad2/3 signaling pathway. Besides, our research had successfully demonstrated the impact of ADSC-Exo and mir-486-3p on animal models. These findings of our study collectively elucidated that ADSC-Exo effectively alleviated H2O2-induced ROS and EndoMT by inhibiting the mir-486-3p/Sirt6/Smad axis.

Apigenin: Molecular Mechanisms and Therapeutic Potential against Cancer Spreading.

Due to its propensity to metastasize, cancer remains one of the leading causes of death worldwide. Thanks in part to their intrinsic low cytotoxicity, the effects of the flavonoid family in the prevention and treatment of various human cancers, both in vitro and in vivo, have received increasing attention in recent years. It is well documented that Apigenin (4',5,7-trihydroxyflavone), among other flavonoids, is able to modulate key signaling molecules involved in the initiation of cancer cell proliferation, invasion, and metastasis, including JAK/STAT, PI3K/Akt/mTOR, MAPK/ERK, NF-κB, and Wnt/ß-catenin pathways, as well as the oncogenic non-coding RNA network. Based on these premises, the aim of this review is to emphasize some of the key events through which Apigenin suppresses cancer proliferation, focusing specifically on its ability to target key molecular pathways involved in angiogenesis, epithelial-to-mesenchymal transition (EMT), maintenance of cancer stem cells (CSCs), cell cycle arrest, and cancer cell death.

Apigenin suppresses epithelial-mesenchymal transition in high glucose-induced retinal pigment epithelial cell by inhibiting CBP/p300-mediated histone acetylation.

Epithelial mesenchymal transition (EMT) is a critical process implicated in the pathogenesis of retinal fibrosis and the exacerbation of diabetic retinopathy (DR) within retinal pigment epithelium (RPE) cells. Apigenin (AP), a potential dietary supplement for managing diabetes and its associated complications, has demonstrated inhibitory effects on EMT in various diseases. However, the specific impact and underlying mechanisms of AP on EMT in RPE cells remain poorly understood. In this study, we have successfully validated the inhibitory effects of AP on high glucose-induced EMT in ARPE-19 cells and diabetic db/db mice. Notably, our findings have identified CBP/p300 as a potential therapeutic target for EMT in RPE cells and have further substantiated that AP effectively downregulates the expression of EMT-related genes by attenuating the activity of CBP/p300, consequently reducing histone acetylation alterations within the promoter region of these genes. Taken together, our results provide novel evidence supporting the inhibitory effect of AP on EMT in RPE cells, and highlight the potential of specifically targeting CBP/p300 as a strategy for inhibiting retinal fibrosis in the context of DR.

E3 ubiquitin ligase UBR5 promotes gemcitabine resistance in pancreatic cancer by inducing O-GlcNAcylation-mediated EMT via destabilization of OGA.

Pancreatic cancer (PC) is among the deadliest malignancies, with an extremely poor diagnosis and prognosis. Gemcitabine (GEM) remains the first-line drug for treating PC; however, only a small percentage of patients benefit from current immunotherapies or targeted therapies. Resistance to GEM is prevalent and affects long-term survival. We found that ubiquitin-protein ligase E3 module N-recognition 5 (UBR5) is a therapeutic target against GEM resistance. UBR5 was markedly upregulated in clinical GEM-resistant PC samples and GEM-resistant PC cells. UBR5 knockdown markedly increased GEM sensitivity in GEM-resistant PC cell lines. UBR5-mediated GEM resistance was accompanied by activation of epithelial-mesenchymal transition (EMT) and could be mitigated by inhibiting EMT. Further analysis revealed that UBR5 promoted GEM resistance in PC cells by enhancing O-GlcNAcylation-mediated EMT. In addition, UBR5 knockdown resulted in increased O-GlcNAase (OGA) levels, an essential negatively regulated enzyme in the O-GlcNAcylation process. We identified a negative association between OGA and UBR5 levels, which further supported the hypothesis that O-GlcNAcylation-mediated GEM resistance induced by UBR5 is OGA-dependent in PC cells. Mechanistic studies revealed that UBR5 acts as an E3 ubiquitin ligase of OGA and regulates O-GlcNAcylation by binding and modulating OGA, facilitating its degradation and ubiquitination. Additionally, high-throughput compound library screening using three-dimensional protein structure analysis and drug screening identified a Food and Drug Administration drug, Y-39983 dihydrochloride, as a potent GEM sensitiser and UBR5 inhibitor. The combination of Y-39983 dihydrochloride and GEM attenuated tumour growth in a mouse xenograft tumour model. Collectively, these data demonstrated that UBR5 plays a pivotal role in the sensitisation of PC to GEM and provides a potential therapeutic strategy to overcome GEM resistance.

PAI-1 mediates acquired resistance to MET-targeted therapy in non-small cell lung cancer.

Mechanisms underlying primary and acquired resistance to MET tyrosine kinase inhibitors (TKIs) in managing non-small cell lung cancer remain unclear. In this study, we investigated the possible mechanisms acquired for crizotinib in MET-amplified lung carcinoma cell lines. Two MET-amplified lung cancer cell lines, EBC-1 and H1993, were established for acquired resistance to MET-TKI crizotinib and were functionally elucidated. Genomic and transcriptomic data were used to assess the factors contributing to the resistance mechanism, and the alterations hypothesized to confer resistance were validated. Multiple mechanisms underlie acquired resistance to crizotinib in MET-amplified lung cancer cell lines. In EBC-1-derived resistant cells, the overexpression of SERPINE1, the gene encoding plasminogen activator inhibitor-1 (PAI-1), mediated the drug resistance mechanism. Crizotinib resistance was addressed by combination therapy with a PAI-1 inhibitor and PAI-1 knockdown. Another mechanism of resistance in different subline cells of EBC-1 was evaluated as epithelial-to-mesenchymal transition with the upregulation of antiapoptotic proteins. In H1993-derived resistant cells, MEK inhibitors could be a potential therapeutic strategy for overcoming resistance with downstream mitogen-activated protein kinase pathway activation. In this study, we revealed the different mechanisms of acquired resistance to the MET inhibitor crizotinib with potential therapeutic application in patients with MET-amplified lung carcinoma.

The anticancer potential of the CLK kinases inhibitors 1C8 and GPS167 revealed by their impact on the epithelial-mesenchymal transition and the antiviral immune response.

The diheteroarylamide-based compound 1C8 and the aminothiazole carboxamide-related compound GPS167 inhibit the CLK kinases, and affect the proliferation of a broad range of cancer cell lines. A chemogenomic screen previously performed with GPS167 revealed that the depletion of components associated with mitotic spindle assembly altered sensitivity to GPS167. Here, a similar screen performed with 1C8 also established the impact of components involved in mitotic spindle assembly. Accordingly, transcriptome analyses of cells treated with 1C8 and GPS167 indicated that the expression and RNA splicing of transcripts encoding mitotic spindle assembly components were affected. The functional relevance of the microtubule connection was confirmed by showing that subtoxic concentrations of drugs affecting mitotic spindle assembly increased sensitivity to GPS167. 1C8 and GPS167 impacted the expression and splicing of transcripts in pathways relevant to tumor progression, including MYC targets and the epithelial mesenchymal transition (EMT). Finally, 1C8 and GPS167 altered the expression and alternative splicing of transcripts involved in the antiviral immune response. Consistent with this observation, depleting the double-stranded RNA sensor DHX33 suppressed GPS167-mediated cytotoxicity on HCT116 cells. Our study uncovered molecular mechanisms through which 1C8 and GPS167 affect cancer cell proliferation as well as processes critical for metastasis.

Anti-metastasis activity of 5,4'-dihydroxy 6,8-dimethoxy 7-O-rhamnosyl flavone from Indigofera aspalathoides Vahl on breast cancer cells.

Breast cancer presents a significant challenge due to its high rates of illness and mortality, necessitating more effective treatment approaches. While traditional treatments offer some benefits, they often lack precision in targeting cancer cells and can inadvertently harm healthy tissues. This study aims to investigate the cytotoxic effects and molecular mechanism of 5,4'-dihydroxy-6,8-dimethoxy-7-O-rhamnosyl flavone (DDR), extracted from Indigofera aspalathoides Vahl, on breast cancer cells (MDA-MB-231). Through various in vitro assays including wound healing, invasion, Western blotting, and immunofluorescence, the impact of DDR on epithelial-mesenchymal transition (EMT) and metastasis was evaluated. Treatment of MDA-MB-231 cells with different DDR concentrations (0-10 µg/mL) resulted in a significant decrease in invasion and migration, accompanied by the downregulation of metastasis-related proteins including VEGF, uPAR, uPA, and MMP-9. DDR treatment also hindered EMT by upregulating E-cadherin and downregulating N-cadherin, Slug, Twist, and Vimentin. Additionally, inhibition of the PI3K/AKT signaling pathway and downregulation of the NF-кB pathway were observed. These findings highlight the potential of DDR as a valuable source of natural compounds with promising anticancer properties, offering opportunities for the development of novel cancer therapies.

LPS-induced monocarboxylate transporter-1 inhibition facilitates lactate accumulation triggering epithelial-mesenchymal transformation and pulmonary fibrosis.

The epithelial-mesenchymal transformation (EMT) process of alveolar epithelial cells is recognized as involved in the development of pulmonary fibrosis. Recent evidence has shown that lipopolysaccharide (LPS)-induced aerobic glycolysis of lung tissue and elevated lactate concentration are associated with the pathogenesis of sepsis-associated pulmonary fibrosis. However, it is uncertain whether LPS promotes the development of sepsis-associated pulmonary fibrosis by promoting lactate accumulation in lung tissue, thereby initiating EMT process. We hypothesized that monocarboxylate transporter-1 (MCT1), as the main protein for lactate transport, may be crucial in the pathogenic process of sepsis-associated pulmonary fibrosis. We found that high concentrations of lactate induced EMT while moderate concentrations did not. Besides, we demonstrated that MCT1 inhibition enhanced EMT process in MLE-12 cells, while MCT1 upregulation could reverse lactate-induced EMT. LPS could promote EMT in MLE-12 cells through MCT1 inhibition and lactate accumulation, while this could be alleviated by upregulating the expression of MCT1. In addition, the overexpression of MCT1 prevented LPS-induced EMT and pulmonary fibrosis in vivo. Altogether, this study revealed that LPS could inhibit the expression of MCT1 in mouse alveolar epithelial cells and cause lactate transport disorder, which leads to lactate accumulation, and ultimately promotes the process of EMT and lung fibrosis.