E-cadherin Protein Levels Research Articles

Assessing the impact of TiO2 nanomaterials on intestinal cells: New evidence for epithelial translocation and potential pro-inflammatory effects.

Understanding the potential impact of nanomaterials (NMs) on human health requires further investigation into the organ-specific nano-bio interplay at the cellular and molecular levels. We showed increased chromosomal damage in intestinal cells exposed to some of in vitro digested Titanium dioxide (TiO2) NMs. The present study aimed to explore possible mechanisms linked to the uptake, epithelial barrier integrity, cellular trafficking, as well as activation of pro-inflammatory pathways, after exposure to three TiO2-NMs (NM-102, NM-103, and NM-105). Using confocal microscopy, we show that all NMs, digested or not, were able to enter different types of intestinal cells. At the physiologically relevant concentration of 14 µg/mL, the digested TiO2-NMs did not compromise the transepithelial resistance, nor the levels of epithelial markers E-cadherin and Zonula occludens protein 1 (ZO-1), of polarized enterocyte monolayers. Nonetheless, all NMs were internalized by intestinal cells and, while NM-102 was retained in lysosomes, NM-103 and NM-105 were able to transverse the epithelial barrier through transcytosis. Moreover, 24 h exposure of 14 and 1.4 μg/mL digested NM-105, promoted interleukin IL-1β expression in activated M1 macrophages, indicating a potential pro-inflammatory action in the gut. Taken together, our findings shed light on the cell-specific nano-bio interplay of TiO2-NMs in the context of the intestinal tract and highlight transcytosis as a potential gateway for their systemic distribution. The potential pro-inflammatory action of digested NM-105 emphasizes the importance of pursuing research into the potential impact of NMs on human health and contribute to the weight of evidence to limit their use in food.

Differential Effects of Sertraline and Penfluridol on EMT and ECM Remodeling in Glioblastoma Cell Lines

Background and Purpose: Glioblastoma multiforme (GBM) is an aggressive brain tumor with poor prognosis due to rapid recurrence, chemoresistance, and limited efficacy of standard therapies. Epithelial-to-mesenchymal transition (EMT) and matrix metalloproteinase (MMP)-mediated extracellular matrix (ECM) remodeling are critical processes in GBM progression and metastasis. The aim of this study is to examine the potential effects of sertraline and penfluridol on the EMT process and gelatinase activity in human glioblastoma cell lines. Methods: U87 and U251 human glioblastoma cells were treated with sertraline and penfluridol at previously identified IC50 doses. Protein levels of EMT markers, E-cadherin, vimentin, Snail, Slug, Twist1, phospho-Akt (p-Akt), and tissue inhibitor of metalloproteinases-2 (TIMP-2), were evaluated using Western blotting. Additionally, the impact of sertraline and penfluridol on the release and activity of MMP-2 and MMP-9 were assessed through gelatin zymography. Results: Both sertraline and penfluridol significantly reduced vimentin expression in U251 cells, indicating inhibition of the mesenchymal phenotype. Conversely, these drugs increased vimentin levels in U87 cells, highlighting cell line-specific differences. Sertraline and penfluridol also increased TIMP-2 levels in U251 cells but not in U87 cells. Neither drug altered MMP-2 or MMP-9 activity in either cell line, suggesting that their effects on ECM remodeling may be mediated through TIMP-2 upregulation rather than direct modulation of gelatinase activity. Conclusion: These findings suggest that sertraline and penfluridol potentially inhibit EMT and reduce ECM degradation in U251 cells but exert contrasting effects in U87 cells. This highlights the heterogeneity of GBM tumors and the importance of personalized therapeutic approaches.

WT161, a selective HDAC6 inhibitor, decreases growth, enhances chemosensitivity, promotes apoptosis, and suppresses motility of melanoma cells.

Histone deacetylase 6 (HDAC6) plays a critical role in tumorigenesis and tumor progression, contributing to proliferation, chemoresistance, and cell motility by regulating microtubule architecture. Despite its upregulation in melanoma tissues and cell lines, the specific biological roles of HDAC6 in melanoma are not well understood. This study aims to explore the functional effects and underlying mechanisms of WT161, a selective HDAC6 inhibitor, in melanoma cell lines. Cell proliferation was assessed using both 2D and 3D cell culture systems, including MTT assays, spheroid growth analyses, and colony formation assays. The interaction between WT161 and the chemotherapeutic agents temozolomide (TMZ) or dacarbazine (DTIC) was evaluated using the Chou-Talalay method. Apoptotic cell death was analyzed through flow cytometry, while migration, adhesion, and invasion assays were conducted to evaluate the motility capacities of melanoma cells. Western blot assays quantified α-tubulin acetylation (Lys40), PARP cleavage, and protein levels of β-catenin and E-cadherin. WT161 significantly reduced cell growth in both 2D and 3D cultures, decreased clonogenic capacity, and showed synergistic interactions with TMZ and DTIC. The inhibitor also induced apoptotic cell death and enhanced TMZ-induced apoptosis. Additionally, WT161 reduced cell migration and invasion while increasing cell adhesion. These effects were linked to changes in β-catenin and E-cadherin levels, depending on the specific cell type evaluated. Our study underscores the pivotal role of HDAC6 in melanoma progression, establishing it as a promising therapeutic target. We provide the first comprehensive evidence of WT161's anti-melanoma effects, setting the stage for further research into HDAC6 inhibitors as a potential strategy for melanoma treatment.

Upregulation of WDR4 mediated by RBFOX2 promotes laryngeal cancer progression through the WDR4/m7G/lncRNA ZFAS1/RBFOX2 axis.

High levels of the N7 methylguanosine (m7G) methyltransferase WD repeat domain 4 (WDR4) are associated with the progression of multiple tumors, including head and neck squamous cell carcinoma. Laryngeal cancer (LC) is the second most common malignant tumor of the head and neck. However, the role of WDR4 in LC remains unclear. Here, we found that WDR4 expression was significantly upregulated in LC tissues and cells. Silencing WDR4 inhibited proliferation, invasion, and epithelial-mesenchymal transition (EMT, manifested by an increase in E-cadherin protein levels and a decrease in N-cadherin and Vimentin protein levels) in TU177 and M4E cells. Furthermore, the levels of m7G and ZFAS1 were significantly upregulated in LC tissues and cells. Mechanistic studies revealed that WDR4 upregulated the levels of ZFAS1 and RBFOX2 proteins by promoting the stability of ZFAS1 in an m7G-dependent manner, and RBFOX2 promoted WDR4 expression by binding to WDR4 mRNA. Overexpression of WDR4 increased m7G and ZFAS1 levels, whereas overexpression of WDR4 with m7G catalytic site mutation had no effect on m7G and ZFAS1 levels in TU177 and M4E cells. Silencing ZFAS1 or RBFOX2 counteracted the promoting effect of WDR4 overexpression on the malignant proliferation of TU177 and M4E cells. TU177 cells transfected with sh-WDR4 lentiviral vectors were intraperitoneally injected into nude mice to construct xenograft tumor models. Knockdown of WDR4 significantly inhibited LC tumor growth in vivo. In conclusion, RBFOX2-mediated upregulation of WDR4 promoted LC progression through the WDR4/m7G/ZFAS1/RBFOX2 axis.

Bushen Huoxue Recipe inhibits endometrial epithelial-mesenchymal transition through the transforming growth factor-β/nuclear factor kappa-B pathway to improve polycystic ovary syndrome-mediated infertility

Objective To investigate the target and mechanism of action of Bushen Huoxue Recipe (BSHX) for the treatment of infertility in polycystic ovary syndrome (PCOS), to provide a basis for the development and clinical application of herbal compounds. Methods Prediction and validation of active ingredients and targets of BSHX for the treatment of PCOS by using network pharmacology-molecular docking technology. In an animal experiment, the rats were randomly divided into four groups (control group, model group, BSHX group, metformin group, n = 16 in each group), and letrozole combined with high-fat emulsion gavage was used to establish a PCOS rat model. Body weight, vaginal smears, and number of embryos were recorded for each group of rats. Hematoxylin-eosin (HE) staining was used to observe the morphological changes of ovarian and endometrial tissues, and an enzyme-linked immunosorbent assay (ELISA) was used to detect the serum inflammatory factor levels. Expression levels of transforming growth factor-β (TGF-β), transforming growth factor beta activated kinase 1 (TAK1), nuclear factor kappa-B (NF-κB), Vimentin, and E-cadherin proteins were measured by western blot (WB). Results Ninety active pharmaceutical ingredients were obtained from BSHX, involving 201 protein targets, of which 160 were potential therapeutic targets. The active ingredients of BSHX exhibited lower binding energy with tumor necrosis factor-α (TNF-α), TGF-β, TAK1, and NF-κB protein receptors (< −5.0 kcal/mol). BSHX significantly reduced serum TNF-α levels in PCOS rats (p < .01), effectively regulated the estrous cycle, restored the pathological changes in the ovary and endometrium, improved the pregnancy rate, and increased the number of embryos. The results of WB suggested that BSHX can down-regulate protein expression levels of TGF-β and NF-κB in endometrial tissue (p < .05), promote the expression level of E-cadherin protein (p < .001), intervene in the endometrial epithelial-mesenchymal transition (EMT) process. Conclusions TGF-β, TAK1, NF-κB, and TNF-α are important targets of BSHX for treating infertility in PCOS. BSHX improves the inflammatory state of PCOS, intervenes in the endometrial EMT process through the TGF-β/NF-κB pathway, and restores endometrial pathological changes, further improving the pregnancy outcome in PCOS.

Cisplatin in Combination with Apigenin Inhibits Human Osteosarcoma Cells Proliferation by Promoting Osteogenic Differentiation: A Mechanistic Insight

Background Osteosarcoma, the predominant primary bone cancer in the pediatric and adolescent population globally, exhibits a relatively low annual incidence but contributes significantly to morbidity and mortality. Purpose: The current study aims to explore the impact of cisplatin, apigenin, and their combination on human osteosarcoma cell line (MG-63) osteosarcoma cells, given the challenges in clinical treatment such as chemotherapy’s adverse effects, resistance development, and relapses. Methods Cytotoxicity assessment using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was conducted for cisplatin, apigenin, and their combination. Apoptotic potential was evaluated through ethidium bromide (EtBr)/acridine orange (AO) dual staining for the combination treatment. Reactive oxygen species (ROS) production and cell cycle arrest were analyzed posttreatment with the cisplatin + apigenin combination using 2′-7′-dichlorodihydrofluorescein diacetate (DCF-DA) staining and fluorescence-activated cell sorting (FACS) analysis, respectively. Proapoptotic and antiapoptotic gene expression was assessed via quantitative polymerase chain reaction (qPCR) analysis. Additionally, messenger ribonucleic acid (mRNA) and protein expression of B-cell-specific Moloney murine leukemia virus integration site 1 (BMIL1) were analyzed in both untreated and cisplatin + apigenin treated cells. Enzyme-linked immunosorbent assay (ELISA) analysis was performed for p16INK4a, E-cadherin, and Notch1. Results Results indicated that the combination treatment significantly inhibited MG-63 cell proliferation compared to individual treatments. Enhanced apoptosis and ROS production were observed in the combination treatment, along with cell cycle arrest at the sub G0- G1 phase. Furthermore, the combination downregulated BMIL1 and Bcl2 expression while upregulating mRNA expression of Bax, Caspase 3, Caspase 9, Apaf-1, and p53. Gene expression results corroborated BMIL1 downregulation in the combination treatment. Additionally, protein levels of p16INK4a and E-cadherin were significantly decreased in the combination treatment compared to individual treatments and untreated control. Conclusions In conclusion, cisplatin and apigenin combination exhibited superior efficacy against osteosarcoma.

YKL-06-061 exerts antitumor effect through G1/S phase arrest by downregulating c-Myc and inhibition of metastasis via SIK1 upregulation in pancreatic cancer.

Pancreatic cancer ranks fourth among cancer-related deaths with a low 5-year overall survival rate of less than 13%. At present, treatment of pancreatic cancer is still based on chemotherapy, but the efficacy is limited. Thus, a novel therapeutic agent for pancreatic cancer therapy is urgently needed. A library of compounds was screened, and YKL-06-061, a selective inhibitor of salt-inducible kinases (SIKs), was discovered for its ability of inhibiting the proliferation and metastasis of pancreatic cancer cells in vitro and reducing the growth of xenografts in nude mice in vivo. The results from transcriptome analysis showed that YKL-06-061 influenced the mRNA levels of many genes related to c-Myc and SIK1 signals. Based on this, it was found that YKL-06-061 induced cell cycle arrest at the G1 phase and decreased the levels of c-Myc, CDK4, and cyclin D1 protein. At the same time, YKL-06-061 inhibited invasion and metastasis of cancer cells, increased the levels of SIK1 and E-cadherin protein, and lowered vimentin and ZEB-1. Moreover, YKL-06-061 effectively enhanced the antiproliferation of gemcitabine or doxorubicin in pancreatic cancer cells in a synergistic manner. Collectively, these findings implicate YKL-06-061 as a promising therapeutic agent for patients with pancreatic cancer.

TRPV4 Mediates Alveolar Epithelial Barrier Integrity and Induces ADAM10-Driven E-Cadherin Shedding.

Transient receptor potential vanilloid 4 (TRPV4) channels have been associated with numerous pulmonary pathologies, including hypertension, asthma, and acute lung injury. However, their role in the alveolar epithelium remains unclear. We performed impedance-based resistance measurements in primary differentiated alveolar epithelial type I (AT1) cells from wild-type (WT) and TRPV4-deficient (TRPV4-/-) C57/BL6J mice to detect changes in AT1 barrier integrity upon TRPV4 activation. Both pharmacological (GSK1016790A) and a low pH-driven activation of TRPV4 were quantified, and the downstream effects on adherens junctions were assessed through the Western blotting of epithelial cadherin (E-cadherin) protein levels. Importantly, a drop in pH caused a rapid decrease in AT1 barrier resistance and increased the formation of a ~35 kDa E-cadherin C-terminal fragment, with both effects significantly reduced in TRPV4-/- AT1 cells. Similarly, the pharmacological activation of TRPV4 in AT1 cells triggered an immediate transient loss of barrier resistance and the formation of the same E-cadherin fragment, which was again diminished by TRPV4 deficiency. Moreover, TRPV4-mediated E-cadherin cleavage was significantly reduced by GI254023X, an antagonist of a disintegrin and metalloprotease 10 (ADAM10). Our results confirm the role of TRPV4 in regulating alveolar epithelial barrier permeability and provide insight into a novel signaling pathway by which TRPV4-induced Ca2+ influx stimulates metalloprotease-driven ectodomain shedding.

6603 Impact of the Monocarbonyl Analogs of Curcumin, C66 and B2BrBC, on the Protein Expression of Epithelial and Mesenchymal Markers in MCF-7 Breast Cancer Cells

Abstract Disclosure: R. Stojchevski: None. A. Lavi: None. J. Bogdanov: None. N. Hadzi-Petrushev: None. M. Mladenov: None. L. Poretsky: None. D.B. Avtanski: None. The synthesis of monocarbonyl analogs of curcumin (MACs) presents a solution to the challenges posed by curcumin, a natural polyphenol extracted from the roots of the turmeric plant (Curcuma longa), which is known for its antioxidant and anti-inflammatory properties. The limitations of curcumin, including poor stability, low bioavailability, and rapid metabolism, hinder its application, and MACs, designed without a β-diketone moiety, address these drawbacks and exhibit enhanced stability and bioavailability. This study aimed to assess the effects of two monocarbonyl analogs of curcumin, (2E,6E)-2,6-bis[(2-trifluoromethyl)benzylidene]cyclohexanone (C66) and (2E,6E)-2,6-bis(2-bromobenzylidene)cyclohexanone (B2BrBC), on epithelial-to-mesenchymal transition (EMT) in MCF-7 breast cancer cells using western blot analysis. Our previous findings indicated that these analogs can potentially affect EMT by modulating the epithelial and mesenchymal gene expression. MCF-7 cells were cultured in complete medium supplemented with EMT-inducing factors for two days, followed by C66 and B2BrBC administration (100 µM) for three additional days. After the experiments, proteins were extracted, and western blot analyses were performed to measure the expression levels of various epithelial and mesenchymal markers (E-cadherin, N-cadherin, SNAI1, and Claudin-1). The results revealed that both C66 and B2BrBC increased the protein levels of the epithelial marker E-cadherin and suppressed those of the mesenchymal marker N-cadherin. Moreover, C66 and B2BrBC decreased the protein expression of the transcription factor SNAI1 and transmembrane protein Claudin-1. Between the two MACs, B2BrBC showed a more pronounced effect on N-cadherin expression, while C66 was more potent in suppressing SNAI1 protein expression. Our findings demonstrate that C66 and B2BrBC counteract EMT, contributing to the potential therapeutic applications of MACs in managing breast cancer progression. Presentation: 6/3/2024

6603 Impact Of The Monocarbonyl Analogs Of Curcumin, C66 And B2BrBC, On The Protein Expression Of Epithelial And Mesenchymal Markers In MCF-7 Breast Cancer Cells

Abstract Disclosure: R. Stojchevski: None. A. Lavi: None. J. Bogdanov: None. N. Hadzi-Petrushev: None. M. Mladenov: None. L. Poretsky: None. D.B. Avtanski: None. The synthesis of monocarbonyl analogs of curcumin (MACs) presents a solution to the challenges posed by curcumin, a natural polyphenol extracted from the roots of the turmeric plant (Curcuma longa), which is known for its antioxidant and anti-inflammatory properties. The limitations of curcumin, including poor stability, low bioavailability, and rapid metabolism, hinder its application, and MACs, designed without a β-diketone moiety, address these drawbacks and exhibit enhanced stability and bioavailability. This study aimed to assess the effects of two monocarbonyl analogs of curcumin, (2E,6E)-2,6-bis[(2-trifluoromethyl)benzylidene]cyclohexanone (C66) and (2E,6E)-2,6-bis(2-bromobenzylidene)cyclohexanone (B2BrBC), on epithelial-to-mesenchymal transition (EMT) in MCF-7 breast cancer cells using western blot analysis. Our previous findings indicated that these analogs can potentially affect EMT by modulating the epithelial and mesenchymal gene expression. MCF-7 cells were cultured in complete medium supplemented with EMT-inducing factors for two days, followed by C66 and B2BrBC administration (100 µM) for three additional days. After the experiments, proteins were extracted, and western blot analyses were performed to measure the expression levels of various epithelial and mesenchymal markers (E-cadherin, N-cadherin, SNAI1, and Claudin-1). The results revealed that both C66 and B2BrBC increased the protein levels of the epithelial marker E-cadherin and suppressed those of the mesenchymal marker N-cadherin. Moreover, C66 and B2BrBC decreased the protein expression of the transcription factor SNAI1 and transmembrane protein Claudin-1. Between the two MACs, B2BrBC showed a more pronounced effect on N-cadherin expression, while C66 was more potent in suppressing SNAI1 protein expression. Our findings demonstrate that C66 and B2BrBC counteract EMT, contributing to the potential therapeutic applications of MACs in managing breast cancer progression. Presentation: 6/3/2024

The Scribble-SGEF-Dlg1 complex regulates E-cadherin and ZO-1 stability, turnover and transcription in epithelial cells.

SGEF (also known as ARHGEF26), a RhoG specific GEF, can form a ternary complex with the Scribble polarity complex proteins Scribble and Dlg1, which regulates the formation and maintenance of adherens junctions and barrier function of epithelial cells. Notably, silencing SGEF results in a dramatic downregulation of both E-cadherin and ZO-1 (also known as TJP1) protein levels. However, the molecular mechanisms involved in the regulation of this pathway are not known. Here, we describe a novel signaling pathway governed by the Scribble-SGEF-Dlg1 complex. Our results show that the three members of the ternary complex are required to maintain the stability of the apical junctions, ZO-1 protein levels and tight junction (TJ) permeability. In contrast, only SGEF is necessary to regulate E-cadherin levels. The absence of SGEF destabilizes the E-cadherin-catenin complex at the membrane, triggering a positive feedback loop that exacerbates the phenotype through the repression of E-cadherin transcription in a process that involves the internalization of E-cadherin by endocytosis, β-catenin signaling and the transcriptional repressor Slug (also known as SNAI2).

Rps3 Attenuates Gastric Precancerous Lesions by Promoting Dendritic Cells Maturation via AKT/β-Catenin Pathway.

This study aimed to investigate the dysregulated proteins and the underlying mechanisms of gastric precancerous lesions. Proteomic and phosphoproteomic methods were used to characterize the proteome and phosphoproteome profiles of N-methyl-N-nitro-N-nitrosoguanidine (MNNG)-induced gastric precancerous lesions. The hub differentially expressed proteins (DEPs) and phosphoproteins (DEPPs) were identified by using differential expression and protein-protein interaction network analyses. Western blot assay, quantitative reverse transcription (qRT)-PCR, and CCK-8 assays detected the expression of Rps3, N-cadherin, E-cadherin, AKT, p-AKT, and β-catenin and verified the roles of Rps3 on the MNNG-induced human gastric epithelial cell line (GES-1) cells. Hub DEPs and phosphoproteins Rps3, Akt1, and Ctnnb1 were significantly correlated with five dendritic cells (DCs) pathways, and Akt1 and Ctnnb1 were significantly negatively correlated with Rps3. MNNG administration markedly reduced the Rps3 mRNA and protein expression levels (all P < 0.05). Overexpression of Rps3 significantly inhibited tumorigenesis of MNNG-induced GES-1 cells (all P < 0.01) and changed the protein levels of N-cadherin, E-cadherin, AKT, p-AKT, and β-catenin. Similarly, SC79 treatment substantially increased the expression of interleukin (IL)-6, IL-10, and vascular endothelial growth factor (all P < 0.05). Rps3 was poorly expressed in precancerous gastric lesions. Correspondingly, overexpression of Rps3 promoted DC maturation via the AKT/β-catenin pathway, inhibiting the progression of gastric precancerous lesions.

Morphine promotes non-small cell lung cancer progression by downregulating E-cadherin via the PI3K/AKT/mTOR pathway

Morphine has been suggested to affect cancer cell dynamics and decrease survival rates in lung cancer patients at specific doses, but the precise mechanisms poorly understood. In this study, we aimed to investigate the molecular mechanisms by which morphine modulates the malignant characteristics of non-small cell lung cancer. Cell proliferation was assessed via the Cell Counting Kit-8 assay, and cell migration and invasion were examined via wound healing and Transwell assays. We employed immunofluorescence staining to evaluate E-cadherin expression in A549 and Lewis lung cancer (LLC) cell lines and immunohistochemistry to evaluate E-cadherin expression in nude mice tumours. Additionally, the in vivo effects of morphine on lung cancer progression were explored in a xenograft tumour experiments, in which naloxone was used as a morphine antagonist. Western blot analysis was performed to detect E-cadherin, phosphorylated mTOR (p-mTOR), mTOR, phosphorylated AKT (p-AKT), AKT, phosphorylated PI3K (p-PI3K), and PI3K protein levels in A549 and LLC cells as well as in tumour samples. Morphine (10 µM) significantly increased the proliferation of A549 and LLC cells in vitro (p < 0.05). It also enhanced the migratory and invasive capacities of these cell lines (p < 0.01). Mechanistically, morphine treatment (10 µM) led to a reduction in the expression of E-cadherin, and an increase in the phosphorylation of PI3K, AKT, and mTOR in A549 and LLC cells (p < 0.01). Morphine treatment (1.5 mg/kg) also reduced E-cadherin expression in xenograft tumours and promoted tumour growth in vivo (p < 0.05). This effect was reversed by naloxone (0.1 mg/kg). The results demonstrated that morphine stimulates the malignant proliferation of A549 and LLC cell lines and promotes xenograft tumour growth. Perhaps by specifically targeting MOR, morphine triggers a signalling cascade that activates the PI3K/AKT/mTOR pathway while inhibiting the EMT marker E-cadherin, which may consequently promote the progression of lung cancer.

MicroRNA-532-3p Modulates Colorectal Cancer Cell Proliferation and Invasion via Suppression of FOXM1.

Colorectal cancer (CRC) is a heterogeneous disease and classified into various subtypes, among which transcriptional alterations result in CRC progression, metastasis, and drug resistance. Forkhead-box M1 (FOXM1) is a proliferation-associated transcription factor which is overexpressed in CRC and the mechanisms of FOXM1 regulation have been under investigation. Previously, we showed that FOXM1 binds to promoters of certain microRNAs. Database mining led to several microRNAs that might interact with FOXM1 3'UTR. The interactions between shortlisted microRNAs and FOXM1 3'UTR were quantitated by a dual-luciferase reporter assay. MicroRNA-532-3p interacted with the 3'UTR of the FOXM1 mRNA transcript most efficiently. MicroRNA-532-3p was ectopically overexpressed in colorectal cancer (CRC) cell lines, leading to reduced transcript and protein levels of FOXM1 and cyclin B1, a direct transcriptional target of FOXM1. Further, a clonogenic assay was conducted in overexpressed miR-532-3p CRC cells that revealed a decline in the ability of cells to form colonies and a reduction in migratory and invading potential. These alterations were reinforced at molecular levels by the altered transcript and protein levels of the conventional EMT markers E-cadherin and vimentin. Overall, this study identifies the regulation of FOXM1 by microRNA-532-3p via its interaction with FOXM1 3'UTR, resulting in the suppression of proliferation, migration, and invasion, suggesting its role as a tumor suppressor in CRC.

Circ_0114866 promotes the progression and EMT of non-small cell lung cancer via miR-653-5p/MYL6B axis

BackgroundNon-small-cell lung cancer (NSCLC) is the most prevalent form of lung cancer. Circular RNA (circRNA) has emerged as a key player in the development of NSCLC by acting as miRNA sponges. However, the precise role of circ_0114866 in regulating NSCLC process is yet to be elucidated. MethodsThe expression of circ_0114866, miR-653-5p, and MYL6B were assessed by qPCR. Cell viability, proliferation, invasion, and migration were investigated using CCK-8, colony formation, Transwell, and wound healing assays. The protein levels of MYL6B, MMP-2, N-cadherin, E-cadherin, and vimentin were evaluated through Western blot analysis. Xenograft tumor model were selected to analyze the impact of circ_0114866 on NSCLC tumor growth. Through circBank or Starbase databases, the binding interactions between miR-653-5p and circ_0114866 or MYL6B were predicted. Subsequently, these interactions were verified by dual-luciferase reporter assay. ResultsThe expression of circ_0114866 and MYL6B were clearly elevated, while miR-653-5p expression was notably reduced in NSCLC tissues and cells. Notably, circ_0114866 knockdown obviously suppressed the proliferation, metastasis, and EMT process in NSCLC cells. Additionally, circ_0114866 functioned as a sponge for miR-653-5p, leading to an increase in MYL6B expression by absorbing miR-653-5p. Furthermore, the inhibitory effects on biological behaviors and EMT process of NSCLC cells induced by circ_0114866 knockdown were reversed by miR-653-5p inhibitor. Moreover, in vivo experiments demonstrated that silencing circ_0114866 resulted in a repression of tumor growth. ConclusionOur findings indicate that circ_0114866 knockdown upregulated MYL6B transcription by sponging miR-653-5p, leading to hinder the progression and EMT process of NSCLC.

Effects of vitamin D deficiency on chronic alcoholic liver injury

Vitamin D deficiency (VDD) has been found among alcoholics. However, little is known about the effect of VDD on alcoholic liver disease and the molecular mechanisms remain unclear. The aim of the current study was to evaluate whether vitamin D was deficient among patients with alcoholic fatty liver disease (AFLD) and the effect of VDD on chronic alcoholic liver injury and possible molecular mechanisms in mice. Our results found that lower 25-hydroxyvitamin D [25(OH)D] concentrations in patients with AFLD. And further analysis found that 25(OH)D is a protective factor in patients with AFLD. Mice experiments indicated that VDD can alter the composition of gut microbiota, down-regulate the protein levels of intestinal tight junction protein Occludin and E-cadherin, up-regulate the expression of inflammatory cytokines (tnf-α, il-1β, il-6, il-8, ccl2, il-10) in liver and colon tissue. And further exacerbated the protein levels of p65,P-IκB,P-p65 in alcoholic liver injury mice. In conclusion, VDD aggravates chronic alcoholic liver injury by activating NF-κB signaling pathway.

Circ_0028826 Promotes Growth and Metastasis of NSCLC via Acting as a Sponge of miR-758-3p to Derepress IDH2 Expression.

Non-small cell lung cancer (NSCLC) is one of the cancers with the highest mortality and morbidity in the world. Circular RNAs (circRNAs) are newly identified players in carcinogenesis and development of various cancers. This study is aimed at exploring the functional effects and mechanism of circ_0028826 in the development of NSCLC. Real-time quantitative PCR (RT-qPCR) was used to detect the expression levels of circ_0028826, IDH2 mRNA, and miR-758-3p. IDH2, Bcl2, Bax, and E-cadherin protein levels were detected using a western blot. Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, wound healing, and transwell assays were used to assess the capacities of proliferation, apoptosis, migration, and invasion. Interaction between miR-758-3p and circ_0028826 or IDH2 was validated using a dual-luciferase reporter assay. The role of circ_0028826 invivo was checked based on a xenograft tumor model. Circ_0028826 was elevated in NSCLC, and its absence inhibited NSCLC cell proliferation, migration, invasion, and induced apoptosis. In terms of mechanism, circ_0028826 increased IDH2 expression by targeting miR-758-3p. In addition, circ_0028826 knockdown also regulated IDH2 by targeting miR-758-3p to inhibit tumor growth invivo. Circ_0028826 promoted the development of NSCLC via regulation of the miR-758-3p/IDH2 axis, providing a new strategy for NSCLC treatment.

Role and mechanism of epithelial-mesenchymal transition in a rat model of bronchopulmonary dysplasia induced by hyperoxia exposure

To investigate the role and mechanism of epithelial-mesenchymal transition (EMT) in a rat model of bronchopulmonary dysplasia (BPD). The experiment consisted of two parts. (1) Forty-eight preterm rats were randomly divided into a normoxia group and a hyperoxia group, with 24 rats in each group. The hyperoxia group was exposed to 85% oxygen to establish a BPD model, while the normoxia group was kept in room air at normal pressure. Lung tissue samples were collected on days 1, 4, 7, and 14 of the experiment. (2) Rat type II alveolar epithelial cells (RLE-6TN) were randomly divided into a normoxia group (cultured in air) and a hyperoxia group (cultured in 95% oxygen), and cell samples were collected 12, 24, and 48 hours after hyperoxia exposure. Hematoxylin-eosin staining was used to observe alveolarization in preterm rat lungs, and immunofluorescence was used to detect the co-localization of surfactant protein C (SPC) and α-smooth muscle actin (α-SMA) in preterm rat lung tissue and RLE-6TN cells. Quantitative real-time polymerase chain reaction and protein immunoblotting were used to detect the expression levels of EMT-related mRNA and proteins in preterm rat lung tissue and RLE-6TN cells. (1) Compared with the normoxia group, the hyperoxia group showed blocked alveolarization and simplified alveolar structure after 7 days of hyperoxia exposure. Co-localization of SPC and α-SMA was observed in lung tissue, with decreased SPC expression and increased α-SMA expression in the hyperoxia group at 7 and 14 days of hyperoxia exposure compared to the normoxia group. In the hyperoxia group, the mRNA and protein levels of TGF-β1, α-SMA, and N-cadherin were increased, while the mRNA and protein levels of SPC and E-cadherin were decreased at 7 and 14 days of hyperoxia exposure compared to the normoxia group (P<0.05). (2) SPC and α-SMA was observed in RLE-6TN cells, with decreased SPC expression and increased α-SMA expression in the hyperoxia group at 24 and 48 hours of hyperoxia exposure compared to the normoxia group. Compared to the normoxia group, the mRNA and protein levels of SPC and E-cadherin in the hyperoxia group were decreased, while the mRNA and protein levels of TGF-β1, α-SMA, and E-cadherin in the hyperoxia group increased at 48 hours of hyperoxia exposure (P<0.05). EMT disrupts the tight connections between alveolar epithelial cells in a preterm rat model of BPD, leading to simplified alveolar structure and abnormal development, and is involved in the development of BPD. Citation:Chinese Journal of Contemporary Pediatrics, 2024, 26(7): 765-773.

Study on the protection of gingival epithelial barrier by interleukin-22 through regulating microbiota and E-cadherin expression

Objective: To investigate the regulatory effect and mechanism of interleukin-22 (IL-22) on the gingival epithelial barrier in the context of periodontal inflammation. Methods: IL-22 knockout (IL-22 KO) mice were constructed, and periodontitis mice models were established through oral gavage with polymicrobial inoculation. DNAs were extracted from the oral plaques of IL-22 KO periodontitis mice group (n=7) and their wild-type littermates periodontitis group (n=7) to establish a periodontitis-related oral microbiota database"PD-RiskMicroDB", determining the relationship between changes in oral microbiota and microbial function in two groups using 16S rRNA sequencing results. Gingival epithelial cells (GEC) were cultured by modified trypsinization method, and were stimulated with 100 μg/L IL-22, Porphyromonas gingivalis (Pg) (multiplicity of infection:100), separately or together for 3 and 12 hours. The experimental groups were as follows: control group (no stimulation), IL-22 group, Pg group and Pg+IL-22 group. The expression of barrier protein E-cadherin in each group at 3 h was detected by immunofluorescence, real-time fluorescence quantitative PCR (RT-qPCR) and Western blotting. Fluorescein isothiocyanate-dextran-mediated epithelial cell permeability experiment was conducted to clarify the changes in permeability of GEC in each group at 3 and 12 h. The mRNA expressions of E-cadherin in the gingival epithelium of wild-type littermates periodontitis group and IL-22 KO periodontitis group were detected by RT-qPCR. Fifteen C57BL/6 wild-type mice were randomly divided into control group (n=5), periodontitis group (n=5) and periodontitis+IL-22 treatment group (n=5). RT-qPCR and immunohistochemistry (IHC) staining were used to detect the expression level of E-cadherin in the gingival epithelium of each group. Results: 16S rRNA sequencing results showed that the composition of oral microbiota changed in IL-22 KO periodontitis group, of which the abundance of bacterial genera related to periodontal tissue invasion was significantly increased (linear discriminant analysis score: 2.22, P=0.009), compared with wild-type littermates periodontitis group. In vitro cell experiments showed that after Pg infection for 3 hours, the cell connections of GEC in Pg group were interrupted, and the fluorescence intensity of E-cadherin was reduced in Pg group compared with the control group. Meanwhile, the mRNA and protein expression levels of E-cadherin (mRNA: 0.69±0.12; protein: 0.60±0.12) were downregulated compared with the control group [mRNA: 1.00±0.00 (P=0.043); protein: 1.04±0.08 (P=0.003)], respectively. The fluorescence intensity of E-cadherin in the Pg+IL-22 group was enhanced compared with Pg group, and expression levels of E-cadherin mRNA (1.16±0.10) and protein (0.98±0.07) in Pg+IL-22 group showed a significant increase compared with Pg group [mRNA: 0.69±0.12 (P=0.005); protein: 0.60±0.12 (P=0.007)]. The result of epithelial permeability test showed that there was no statistical difference in epithelial permeability among control group, Pg group, IL-22 group and Pg+IL-22 group with treatment for 3 hours (F=0.20, P=0.893). While when the treatment time turned to be 12 hours, the epithelial barrier permeability showed a significant increase in Pg group (1.39±0.15) compared with control group (1.00±0.00, P=0.027), and a decrease in Pg+IL-22 group (1.02±0.18) compared with Pg group (1.39±0.15, P=0.034). In vivo, the mRNA expression of E-cadherin in the gingival epithelium of IL-22 KO periodontitis group decreased significantly (0.32±0.21) compared with wild-type littermates periodontitis group (1.01±0.01) (t=5.70, P=0.005). Moreover, RT-qPCR and IHC staining results showed that the mRNA expression level of E-cadherin (0.40±0.07) and absorbance value of E-cadherin positive expression (0.02±0.00) in gingival epithelial tissue of periodontitis group were both significantly down-regulated compared with control group [mRNA: 1.00±0.00 (P=0.005); absorbance value of E-cadherin positive expression: 0.04±0.01 (P=0.006)]. Meanwhile, the mRNA expression level of E-cadherin (1.06±0.24) and the absorbance value of E-cadherin positive expression (0.03±0.01) were both observed increase in periodontitis+IL-22 treatment group compared with periodontitis group (P=0.003, P=0.039). Conclusions: IL-22 may exert a protective effect on the gingival epithelial barrier in an inflammatory environment by regulating the invasiveness of oral microbiota and the expression of host barrier protein.

Andrographolide targets EGFR to impede epithelial–mesenchymal transition in human breast cancer cells

Despite the primary surgical treatment for breast cancer patients, malignant invasiveness and metastasis remain threatening factors for women with breast cancer. As chemotherapy yields unsatisfactory results, it prompted us to search for effective natural agents with few side-effects. Although andrographolide (ADGL), a natural diterpenoid lactone isolated from Andrographis paniculata, presents anticancer effects, the molecular mechanism remains unknown. Initially, on comparing the expression of proteins related to epithelial–mesenchymal transition (EMT) between nonmetastatic cancer MCF7 cells and highly metastatic cancer MDA-MB-231 cells, we found that MDA-MB-231 cells exhibit higher protein levels of N-cadherin and vimentin and lower protein levels of E-cadherin when compared to MCF7 cells. Moreover, MDA-MB-231 cells also exhibited higher EGFR expression and activity, higher STAT1 activity and abundant HDAC4 expression. To elucidate whether these proteins are closely associated with EMT, EGFR, STAT1 or HDAC4, the proteins were silenced in MDA-MB-231 breast cancer cells by their specific siRNAs. We found that silencing these proteins reduced EMT, indicating an important role of EGFR, STAT1 and HDAC4 in EMT progression. When we treated MDA-MB-231 cells with ADGL as a potential therapeutic drug, we found that ADGL treatment inhibited cell migration and invasion. Furthermore, it also recovered E-cadherin expression and decreased N-cadherin and vimentin protein levels. ADGL treatment reduced EGFR expression at a lower concentration (1 μg/mL); however, STAT1 activity and HDAC4 expression was reduced by a higher concentration (5 μg/mL) of ADGL. Moreover, we observed that the combined treatment with ADGL and siRNAs against these proteins highly sensitized the MDA-MB-231 cells to apoptosis compared to that with ADGL and control siRNA. Collectively, our results suggest that ADGL targets EGFR, thereby inhibiting EMT in human breast cancer cells.