Downregulation Of E-cadherin Research Articles

E-Cadherin-Mediated Cell-Cell Adhesion and Invasive Lobular Breast Cancer.

E-cadherin is a transmembrane protein and central component of adherens junctions (AJs). The extracellular domain of E-cadherin forms homotypic interactions with E-cadherin on adjacent cells, facilitating the formation of cell-cell adhesions, known as AJs, between neighbouring cells. The intracellular domain of E-cadherin interacts with α-, β- and p120-catenins, linking the AJs to the actin cytoskeleton. Functional AJs maintain epithelial tissue identity and integrity. Transcriptional downregulation of E-cadherin is the first step in epithelial-to-mesenchymal transition (EMT), a process essential in development and tissue repair, which, in breast cancer, can contribute to tumour progression and metastasis. In addition, loss-of-function mutations in E-cadherin are a defining feature of invasive lobular breast cancer (also known as invasive lobular carcinoma (ILC)), the second most common histological subtype of breast cancer. ILC displays a discohesive, single-file invasive growth pattern due to the loss of functional AJs. Despite being so prevalent, until recently there has been limited ILC-focused research and historically ILC patients have often been excluded from clinical trials. Despite displaying a number of good prognostic indicators, such as low grade and high rates of estrogen receptor positivity, ILC patients tend to have similar or poorer outcomes relative to the most common subtype of breast cancer, invasive ductal carcinoma (IDC). In ILC, E-cadherin loss promotes hyperactivation of growth factor receptors, in particular insulin-like growth factor 1 receptor, anoikis resistance and synthetic lethality with ROS1 inhibition. These features introduce clinical vulnerabilities that could potentially be exploited to improve outcomes for ILC patients, for whom there are currently limited tailored treatments available.

Anti-Inflammatory 8-Shogaol Mediates Apoptosis by Inducing Oxidative Stress and Sensitizes Radioresistance in Gastric Cancer.

Radiotherapy is a powerful tumor therapeutic strategy for gastric cancer patients. However, radioresistance is a major obstacle to kill cancer cells. Ginger (Zingiber officinale Roscoe) exerts a potential function in various cancers and is a noble combined therapy to overcome radioresistance in gastric cancer radiotherapy. In this study, we suggested that 8-shogaol, a monomethoxybenzene compound extracted from Zingiber officinale Roscoe, has an anti-cancer and anti-inflammatory activity. In lipopolysaccharide (LPS)-induced inflammatory murine models in vivo and in vitro, 8-shogaol suppressed LPS-mediated cytokine production, including COX-2, TNFα, IL-6, and IL-1β. In xenograft mouse models of AGS gastric cancer cell lines, 8-shogaol reduced tumor volume. In gastric cancer cell lines AGS and NCI-N87, 8-shogaol reduced cell viability and increased caspase-3 activity and cytotoxicity LDH. However, combined with Z-VAD-FMK, 8-shogaol blocked caspase-dependent apoptotic cell death. 8-Shogaol induced intracellular reactive oxygen species (ROS) production, intracellular calcium (Ca2+) release, and endoplasmic reticulum (ER) stress response via the PERK-CHOP signaling pathway. Thapsigargin (TG), an ER stressor, mediated synergistic apoptosis and cell death in 8-shogaol-treated AGS and NCI-N87 cell lines. Nevertheless, loss of PERK or CHOP function suppressed ER-stress-induced apoptosis and cell death in 8-shogaol-treated AGS and NCI-N87 cell lines. 8-Shogaol-induced NADPH oxidase 4 (NOX4) activation is related to ROS generation. However, NOX4 knockdown and ROS inhibitors DPI or NAC blocked ER-stress-induced apoptosis by suppressing the inhibition of cell viability and the enhance of caspase-3 activity, intracellular ROS activity, and cytotoxicity LDH in 8-shogaol-treated AGS and NCI-N87 cell lines. Radioresistant gastric cancer models (AGSR and NCI-N87R) were developed and combined with 8-shogaol and radiation (2 Gy) to overcome radioresistance via the upregulation of N-cadherin and vimentin and the downregulation of E-cadherin. Therefore, these results indicated that 8-shogaol is a novel combined therapeutic strategy in gastric cancer radiotherapy.

Chromatin licensing and DNA replication factor 1 as a potential prognostic and diagnostic biomarker for gastric cancer

Accurate and timely genetic material replication is essential for preserving genomic integrity. The replication process begins with chromatin licensing and DNA replication factor 1 (CDT1). It has been demonstrated that dysregulated CDT1 expression causes genomic instability, damages DNA, and may even cause cancer. Although this protein is overexpressed in several malignancies, its significance in gastric cancer is still unknown. This work aims to investigate the biological function and molecular mechanism of CDT1 in gastric cancer. Bioinformatics studies were carried out using TCGA database, Kaplan–Meier and GEPIA online data analysis software. The expression of CDT1 in stomach cancer tissues was determined by immunohistochemistry, and its relationship to clinicopathological features was examined. Using siRNA and cell function experiments, the impact of CDT1 expression on the capacity of gastric cancer cell lines to proliferate, migrate, and invade was investigated. In gastric cancer tissues, CDT1 is overexpressed and is linked to a dismal prognosis. Through the up-regulation of M-cyc, MCM5 (microchromosome maintenance protein 5), CyclinD1, N-cadherin, and the down-regulation of E-cadherin, CDT1 facilitated the proliferation and invasion of gastric cancer cells. The study’s findings shed insight on the possible molecular processes behind CDT1’s function in promoting the start and progression of gastric cancer and demonstrate the potential predictive and diagnostic use of CDT1 expression in gastric cancer.

TLE1 corepressor promotes gefitinib resistance in lung cancer A549 cells via E‑cadherin silencing.

As a putative lung specific oncogene, the transducin-like enhancer of split 1 (TLE1) corepressor drives an anti-apoptotic and pro-epithelial-mesenchymal transition (EMT) gene transcriptional programs in human lung adenocarcinoma (LUAD) cells, thereby promoting anoikis resistance and tumor aggressiveness. Through its survival- and EMT-promoting gene regulatory programs, TLE1 may impact drug sensitivity and resistance in lung cancer cells. In the present study, a novel function of TLE1 was uncovered as an inhibitor of the antitumor effects of the epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) gefitinib in the human LUAD cell line A549, which exhibits moderate sensitivity to EGFR-TKI. While upregulation of TLE1 expression potently inhibited the proliferation inhibitory and apoptotic effects of gefitinib in A549 cells, downregulation of endogenous TLE1 in these cells enhanced their sensitivity to gefitinib. In experimentally derived gefitinib-resistant A549 cells (A549GR) that have acquired EMT, TLE1 expression is upregulated as compared with parental A549 cells, and acute ablation of TLE1 expression is sufficient to partially restore gefitinib sensitivity and attenuate EMT phenotype. Mechanistic studies showed that TLE1 confers gefitinib resistance in A549 cells in part via downregulation of E-cadherin, a known potentiator of EGFR-TKI sensitivity and apoptosis induction. Importantly, the TLE1/E-cadherin transcriptional axis is negatively regulated by gefitinib to trigger apoptosis via the Bcl-2-inhibitor of transcription 1 cell death pathway. In conclusion, these results indicate a novel role of TLE1 in modulating EGFR-TKI sensitivity in lung cancer cells via regulation of E-cadherin expression, and its upregulation may potentiate EGFR-TKI resistance in LUAD.

Mefunidone Inhibits Inflammation, Oxidative Stress, and Epithelial-Mesenchymal Transition in Lens Epithelial Cells.

Inflammation, oxidative stress, and epithelial-mesenchymal transition (EMT) play crucial roles in forming posterior capsular opacification (PCO), particularly in fibrotic PCO. Here we investigated the protective effects of mefunidone (MFD), a novel compound with potent antifibrotic properties, which could be useful in preventing PCO. We utilized an extracapsular lens extraction (ECLE) surgery in mice to simulate the development of PCO in vivo. Treatment was performed immediately postsurgery through the intracameral injection of MFD solution. Expression levels of EMT and inflammatory markers were analyzed using Western blot, qRT-PCR, immunofluorescence, and hematoxylin and eosin staining. Additionally, the oxidative stress indicator malondialdehyde and glutathione expression were monitored to assess the oxidative stress response. In vitro experiments, TGF-β2, and H2O2 were used to treat lens epithelial cells to induce EMT and oxidative stress models, respectively. These models were employed to explore the effects of MFD and investigate its underlying mechanisms. Compared to the model group, the group treated with anterior chamber MFD injection effectively suppressed inflammation, oxidative stress, and fibrotic responses within the capsular bag after ECLE and partially inhibited the downregulation of the epithelial marker E-cadherin. To further elucidate the underlying mechanisms, we discovered that MFD treatment in vitro remarkably reduced inflammation, decreased the production of reactive oxygen species, and suppressed the phosphorylation of TGF-β/SMAD as well as MAPK/ERK, thereby inhibiting the occurrence of EMT. Our findings substantiate the efficacy of MFD in treating PCO and provide insights into its potential mechanisms of action.

TMOD-03.BRAFV600E MUTATION INDUCES TWIST1 UPREGULATION ASSOCIATED WITH MIGRATION AND CEREBRAL FLUID DISSEMINATION IN GLIOBLASTOMA

Abstract INTRODUCTION BRAFV600E-mutant glioblastoma (GBM) with epithelioid features frequently show cerebrospinal fluid dissemination (CSFD), which results in poor prognoses. BRAF mutation is worth investigating since BRAF or downstream MEK inhibitors show dramatic response for BRAFV600E-mutant GBM including CSFD. This suggests BRAF mutation could play a role for inducing the clinical manifestation of CSFD found in newly diagnosed and recurrent BRAFV600E-mutant GBM. Because, BRAFV600E-mutant GBM often recur with CSFD, elucidating the mechanism by which BRAFV600E-mutant GBM exhibits CSFD is important to improve prognosis. (Objective) To elucidate the molecular mechanism of CSFD involved in BRAFV600E-mutant GBM. METHODS We introduced the heterozygous BRAFV600E mutation in human induced pluripotent stem cells (iPSC) in the context of GBM genetic alterations, CDKN2A/2B, and PTEN deletion, TERT promoter mutation and with EGFRvIII overexpression. We implanted these iPSC-derived neural progenitor cells into immunodeficient mouse brains to establish a BRAFV600E-mutant GBM model. At the same time, we created a model with the same genetic background without BRAFV600E. We compared their gene expression, pathology, and migration patterns to identify BRAFV600E specific characteristics. RESULTS RNA sequencing revealed BRAFV600E-mutant tumors upregulated migration, and downregulated cell-to-cell adhesion genes. TWIST1 was one of the most upregulated genes, and was validated by qPCR. Concomitant with TWIST1 expression we detected downregulation of E-cadherin. The BRAFV600E GBM model histologically showed a cluster-like invasion phenotype, while non-BRAF tumors showed homogenous invasion with typical GBM pathological findings. Immunohistochemical staining showed relatively high TWIST1 expression in cluster-like tumor cells of BRAFV600E tumors. Upon re-engraftment of primary tumor-derived cells, secondary BRAFV600E tumors presented leptomeningeal dissemination. TWIST1 knockdown resulted in a decrease in the migratory ability of our BRAFV600E model in vitro, and is under investigation in vivo. CONCLUSION BRAV600E mutation induces TWIST1 upregulation, and might facilitate migration and CSFD. This work nominates TWIST1 and its regulated genes as targets for BRAFV600E-mutant GBM with CSFD.

Reduced Proline-Rich Tyrosine Kinase 2 Promotes Tumor Metastasis by Activating Epithelial-Mesenchymal Transition in Colorectal Cancer.

Proline-rich tyrosine kinase 2 (PYK2) is involved in the occurrence, proliferation, migration, and invasion of various tumors. However, few studies have reported the role of PYK2 in colorectal cancer (CRC). To explore the effects of PYK2 on CRC metastasis and elucidate the detailed molecular mechanisms involved. The expression and prognosis value of PYK2 in CRC prognosis were analyzed using data from The Cancer Genome Atlas (TCGA). PYK2 was knocked down or overexpressed in human CRC cell line, HCT116. Cell proliferation, migration, invasion, and cycle changes were analyzed using CCK-8, Transwell, and flow cytometry assays. Western blotting and quantitative real-time PCR were performed to detect the mRNA and protein levels of cell proliferation and epithelial-mesenchymal transition (EMT) indicators. Fluorescence staining was performed to examine the cytoskeleton. Lower expression of PYK2 was observed in CRC tissues and associated with poor prognosis and metastasis in patients with CRC in TCGA database. PYK2 knockdown significantly induced the migration and invasion of CRC cells but did not affect cell proliferation or cycle. Immunofluorescence staining of phalloidin showed that the downregulation of PYK2 increased the cytoskeleton in CRC cells. Moreover, low expression of PYK2 induced the downregulation of E-cadherin and upregulation of snail and vimentin by activating Wnt/β-catenin signaling, thus promoting EMT in CRC cells. Low PYK2 expression was found in tumor tissues, especially metastases, and significantly correlated with patient prognosis. Moreover, decreased PYK2 induces EMT by activating Wnt/β-catenin signaling, which is the potential mechanism of CRC metastasis. Regulating the expression of PYK2 to suppress tumor cell metastasis may represent a promising therapeutic strategy for metastatic CRC.

Electrical Impedance Spectroscopy as a Tool to Detect the Epithelial to Mesenchymal Transition in Prostate Cancer Cells.

Prostate cancer (PCa) remains a significant health threat, with chemoresistance and recurrence posing major challenges despite advances in treatment. The epithelial to mesenchymal transition (EMT), a biochemical process where cells lose epithelial features and gain mesenchymal traits, is linked to chemoresistance and metastasis. Electrical impedance spectroscopy (EIS), a novel label-free electrokinetic technique, offers promise in detecting cell phenotype changes. In this study, we employed EIS to detect EMT in prostate cancer cells (PCCs). PC3, DU145, and LNCaP cells were treated with EMT induction media for five days. EIS characterization revealed unique impedance spectra correlating with metastatic potential, distinguishing DU145 EMT+ and EMT- cells, and LNCaP EMT+ and EMT- cells (in combination with dielectrophoresis), with comparisons made to epithelial and mesenchymal controls. These changes were supported by shifts in electrical signatures, morphologies, and protein expression, including the downregulation of E-cadherin and upregulation of vimentin. No phenotype change was observed in PC3 cells, which maintained a mesenchymal phenotype. EMT+ cells were also distinguishable from mixtures of EMT+ and EMT- cells. This study demonstrates key advancements: the application of EIS and dielectrophoresis for label-free EMT detection in PCCs, characterization of cell electrical signatures after EMT, and EIS sensitivity to EMT transitions. Detecting EMT in PCa is important to the development of more effective treatments and overcoming the challenges of chemoresistance.

Modeling epithelial-mesenchymal transition in patient-derived breast cancer organoids.

Cellular plasticity is enhanced by dedifferentiation processes such as epithelial-mesenchymal transition (EMT). The dynamic and transient nature of EMT-like processes challenges the investigation of cell plasticity in patient-derived breast cancer models. Here, we utilized patient-derived organoids (PDOs) as a model to study the susceptibility of primary breast cancer cells to EMT. Upon induction with TGF-β, PDOs exhibited EMT-like features, including morphological changes, E-cadherin downregulation and cytoskeletal reorganization, leading to an invasive phenotype. Image analysis and the integration of deep learning algorithms enabled the implantation of microscopy-based quantifications demonstrating repetitive results between organoid lines from different breast cancer patients. Interestingly, epithelial plasticity was also expressed in terms of alterations in luminal and myoepithelial distribution upon TGF-β induction. The effective modeling of dynamic processes such as EMT in organoids and their characteristic spatial diversity highlight their potential to advance research on cancer cell plasticity in cancer patients.

E-Cadherin and Snail Immunohistochemical Expression in Multiple Ipsilateral Breast Carcinoma Disease

Abstract Background As compared to invasive breast cancer- no special type (IBC-NST), Invasive lobular cancer (ILC) traditionally shows loss of function of the E-cadherin- catenin membrane complex, frequent downregulation of E-cad expression and is significantly more associated with Multiple Ipsilateral Breast Carcinoma (MIBC). Nevertheless, E cadherin downregulation was also described in MIBC with IBC-NST phenotype. MIBC was suggested to have a more aggressive biologic nature than unifocal disease, Epithelial mesenchymal transition (EMT) has been suggested as an attribute to such poorer prognosis. The transcription factor Snail commonly acts as one of the earliest switches of the EMT process and E-cadherin downregulation is one of its major downstream effects. Causation and association links between EMT and MIBC in different types of breast cancer needs further elucidation. Objective to investigate whether the association betweenE-cadherin downregulation and MIBC is attributed to EMT and whether such association and expression of EMT markers is differentially presented in ILC and IBC-NST. Methods This study was conducted retrospectively on 77 breast cancer cases diagnosed at Ain Shams University Hospitals (2012-2022). We included all ILC cases meeting study criteria (20 unifocal, 14 MIBC) and randomly selected sets of IBC- NST cases (13 unifocal, 16 MIBC) and mixed ductolobular IBC (7 unifocal, 7 MIBC). Immunohistochemical expression of E-cadherin and Snail was evaluated and compared in different study groups with subsequent statistical analysis. Results E- cadherin expression showed 15/40 (37.5%) negative expression, 15/40 (37.5%) with low expression, and 10/40 (25%) with high expression in the unifocal group, compared to 14/37 (37.8%) negative result, 13/37 (35.1%) low E-cadherin expression, and 10/37 (27%) with high E-cadherin expression in the MIBC group. There was no significant difference in E-cadherin expression regarding focality neither in all cases (p-value: 0.97) nor in each of the histological subgroups (p-values: 0.34 for IBC- NST, 1.00 for mixed, 0.2 for ILC). On the other hand, Snail expression was extensive in 24/37 MIBC cases (64.86%) as compared to 17/40 unifocal cases (42.5%), this was statistically significant (p-value: 0.038). Conclusions E-cadherin downregulation doesn’t seem to contribute to MIBC whether ILC, mixed or IBC-NST, however snail overexpression is significantly associated with MIBC. This suggests that EMT may have a role in multiplicity of IBC.

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).

A Retrospective Study on the Expression of E-Cadherin in Endometrial Carcinoma.

E-cadherin is a cell adhesion molecule crucial for maintaining cellular integrity and survival. E-cadherin is the focus of this study, which aims to evaluate its immunohistochemical staining patterns in endometrial carcinoma (EC). Material and methods In this retrospective study, 25 formalin-fixed, paraffin-embedded tissue blocks of EC were retrieved from the Department of Pathology at Saveetha Medical College. These samples, collected between September 2020 and May 2023, were identified using unique histopathology numbers. Results The analysis revealed that E-cadherin expression decreased as the endometrial tissue progressed from normal to carcinoma. This reduction was more pronounced in cancers with greater depth of invasion and in more advanced stages compared to those with less invasive depth and earlier stages. Additionally, E-cadherin expression was higher in grade 1 tumors but became heterogeneous or negative in grade 3 tumors. Conclusion The downregulation of E-cadherin is likely due to disruptions in the cadherin-catenin complex, which is linked to the potential for local and distant metastasis in cancer. This study underscores the significance of cell adhesion molecule expression in predicting the prognosis of EC.

Pneumolysin contributes to dysfunction of nasal epithelial barrier for promotion of pneumococcal dissemination into brain tissue.

Streptococcus pneumoniae is one of the major pathogens responsible for bacterial meningitis and neurological sequelae. The present study was conducted to identify a non-hematogenous route used by S. pneumoniae to gain access to brain tissue without causing bacteremia or pneumonia, as well as bacterial and host factors involved in this process. To investigate the molecular mechanisms and dissemination pathways of pneumococcal infection in brain tissue, mice were intranasally inoculated with S. pneumoniae strain EF3030, a clinical isolate from a patient with otitis media. Pneumococci were isolated from the frontal olfactory bulb, caudal cerebrum, and cerebellum, with neither bacteremia nor pneumonia observed in the present model. Immunostaining imaging revealed the presence of S. pneumoniae organisms in olfactory nerve fibers. Knockout of the ply gene encoding pneumolysin (PLY) markedly compromised the ability of the bacterial organisms to disseminate into brain tissue, whereas the dissemination efficiency of the complemented strain was restored to nearly the same level as the wild type. Notably, distinct upregulation of Gli1 and Snail1, which are involved in the transcriptional repression of junctional proteins, along with downregulation of E-cadherin, was detected in nasal lavage samples from mice infected with the wild-type or complemented strain, but not in those from mice infected with the ply mutant. Taken together, the present findings indicate that PLY induces Gli1-Snail1-dependent dysfunction of the nasal epithelial barrier, thus allowing pneumococcal dissemination to brain tissue that occurs in a non-hematogenous manner.IMPORTANCEBacterial meningitis, considered to be caused by bacteremia, can lead to blood-brain barrier disruption and bacterial dissemination into the central nervous system. Despite the availability of intravenously administered antibiotics with cerebrospinal fluid transferability, bacterial meningitis remains associated with high rates of morbidity and mortality. Here, we utilized Streptococcus pneumoniae strain EF3030, clinically isolated from otitis media, for the construction of a murine infection model to investigate the molecular mechanisms by which nasally colonized pneumococci disseminate into brain tissue. The obtained findings indicate that pneumolysin (PLY) induces Gli1-Snail1-dependent dysfunction of the nasal epithelial barrier, which facilitates pneumococcal dissemination to brain tissue in a non-hematogenous manner. Our results support the existence of an alternative route by which S. pneumoniae can reach the central nervous system and indicate the need for the development of novel therapeutic strategies, which would be an important contribution to the clinical management of bacterial meningitis.

Cancer Cell-Selective Inhibition of Migration by Styrenic Catiomer Emulsions.

Cancer metastasis remains the most formidable cause of mortality and morbidity in cancer patients. Developing an effective and economical method toward cancer antimetastatic strategy demands immediate attention in anticancer therapy. Herein, we followed a cost-effective greener method for preparing a small family of amphiphilic catiomers with varied styrene content (45, 63, and 83%), which revealed the unique potential of promoting normal cell migration while retarding cancer metastasis. The styrenic polymers formed micellar self-assembly in aqueous phase and exhibited a cationic charge. Polymers were quite nontoxic up to 200 μg/mL concentration toward human embryonic kidney cell HEK293 as well as human, triple negative breast cancer cell MDAMB-231, mouse melanoma cell B16F10, and human oral squamous carcinoma cell FaDu. Confocal imaging and fluorescence activated cell sorting (FACS) showed effective incorporation of polymers within cells. Interestingly, the polymer-treated HEK293 cells underwent prominent wound healing in scratch assay. However, the as-synthesized polymer-treated cancer cells resisted migration as analyzed from the scratch assay. A mechanistic study using immunoblotting assay established upregulation of migratory proteins vimentin and TGF-β and downregulation of E-cadherin in normal HEK293 cells. Remarkably, this trend was completely reversed in cancer cell MDAMB-231. This study describes the extraordinary potential of styrenic catiomers as wound healers for normal cells while inhibiting cancer metastasis.

Exploring the Role and Pathophysiological Significance of Aldehyde Dehydrogenase 1B1 (ALDH1B1) in Human Lung Adenocarcinoma

Aldehyde dehydrogenases (ALDHs) constitute a diverse superfamily of NAD(P)+-dependent enzymes pivotal in oxidizing endogenous and exogenous aldehydes to carboxylic acids. Beyond metabolic roles, ALDHs participate in essential biological processes, including differentiation, embryogenesis and the DNA damage response, while also serving as markers for cancer stem cells (CSCs). Aldehyde dehydrogenase 1B1 (ALDH1B1) is a mitochondrial enzyme involved in the detoxification of lipid peroxidation by-products and metabolism of various aldehyde substrates. This study examines the potential role of ALDH1B1 in human lung adenocarcinoma and its association with the CSC phenotype. To this end, we utilized the lung adenocarcinoma cell line A549, engineered to stably express the human ALDH1B1 protein tagged with green fluorescent protein (GFP). Overexpression of ALDH1B1 led to notable changes in cell morphology, proliferation rate and clonogenic efficiency. Furthermore, ALDH1B1-overexpressing A549 cells exhibited enhanced resistance to the chemotherapeutic agents etoposide and cisplatin. Additionally, ALDH1B1 overexpression correlated with increased migratory potential and epithelial–mesenchymal transition (EMT), mediated by the upregulation of transcription factors such as SNAI2, ZEB2 and TWIST1, alongside the downregulation of E-cadherin. Moreover, Spearman’s rank correlation coefficient analysis using data from 507 publicly available lung adenocarcinoma clinical samples revealed a significant correlation between ALDH1B1 and various molecules implicated in CSC-related signaling pathways, including Wnt, Notch, hypoxia, Hedgehog, retinoic acid, Hippo, NF-κΒ, TGF-β, PI3K/PTEN-AKT and glycolysis/gluconeogenesis. These findings provide insights into the role of ALDH1B1 in lung tumor progression and its relation to the lung CSC phenotype, thereby offering potential therapeutic targets in the clinical management of lung adenocarcinoma.

Anlotinib reverses osimertinib resistance via inhibiting epithelial-to-mesenchymal transition and angiogenesis in non-small cell lung cancer.

In the present, we aimed to investigate the effect of anlotinib on the potential reversal of osimertinib resistance by inhibiting the formation of epithelial-to-mesenchymal transition (EMT) and angiogenesis. In a clinical case, anlotinib reversed osimertinib resistance in Non-small cell lung cancer (NSCLC). We performed an immunohistochemical experiment on tumor tissues from three non-small cell lung cancer patients exhibiting osimertinib resistance to analyze alterations in the expression levels of EMT markers and vascular endothelial growth factor A (VEGFA) before and after osimertinib resistance. The results revealed the downregulation of E-cadherin, coupled with the upregulation of vimentin and VEGFA in tumor tissues of patients exhibiting osimertinib resistance, compared with the expression in tissues of patients before taking osimertinib. Subsequently, we established osimertinib-resistant cell lines and found that the osimertinib-resistant cells acquired the EMT features. Then, we analyzed the synergistic effects of the combination therapy to verify whether anlotinib could reverse osimertinib resistance by inhibiting EMT. The expression levels of VEGFA and micro-vessels were analyzed in the combination group in vitro. Finally, we explored the reversal of osimertinib resistance in combination with anlotinib in vivo with 20 nude mice. The combined treatment of osimertinib and anlotinib effectively prevented the metastasis of resistant cells, which also inhibited tumor growth, exerted anti-tumor activity, and ultimately reversed osimertinib resistance in mice. The co-administration of osimertinib and anlotinib demonstrated their synergistic efficacy in inhibiting EMT and angiogenesis in three NSCLC patients, ultimately reversing osimertinib resistance.

Sishen pills inhibit inflammatory dendritic cell differentiation via miR-505–3p mediated E-cadherin downregulation in ulcerative colitis

BackgroundUlcerative colitis (UC) is an autoimmune disease that is highly susceptible to recurrence, which is still a lack of effective drugs with minor side effects in clinic. Intervention of inflammatory differentiation of dendritic cells (DCs) might be an effective strategy to treat UC. Sishen Pills (SSP) is a classic Chinese herbal formula which has been demonstrated the protective effect of UC, but the mechanism remains unclear. PurposeTo elucidate the protective effects of SSP against UC in mice and reveal its regulatory mechanism of DCs and the key active ingredients for the UC treatment based on transcriptomics, network pharmacology and experiments validation in vivo and vitro. MethodThe key active ingredients of SSP were detected and screened integrating LC-MS/MS and network pharmacology. A mouse UC model was induced with 3% sodium dextran sulfate and treated with SSP for 14 days to evaluate the efficacy. ELISA was used to detect the levels of IL-6, IL-1β and TNF-α in the colon; flow cytometry was used to detect the expression levels of DCs and their subpopulations; whole transcriptomic sequencing of differential RNAs in the colon and RT-PCR to detect key miRNAs to verify the sequencing results. Mouse bone marrow-derived dendritic cells (BMDCs) were isolated, an inflammatory model was constructed using 100 ng/ml LPS, and the effects of SSP on DC proliferation and apoptosis and their surface co-stimulatory molecule expression were examined; IL-6, IL-1β, TNF-α levels were measured by ELISA; RT-PCR and WB were performed to detect miR-505–3p, CDH1, E-cadherin expression. BMDCs with low expression of miR-505–3p were constructed by lentiviral transfection for further validation. The potential key ingredient was re-validated in vivo and vitro experiment. ResultsAnimal experiments showed that SSP alleviated DSS-induced UC symptoms and colonic pathological injury in mice, and inhibited IL-6, IL-1β, TNF-α secretion and inflammatory DC proliferation and activation maturation. Network pharmacology predicted that evodiamine, isobavachalcone, curcumin, and engenol may play a key role in SSP. RNA sequencing revealed that miR-505–3p, as the differential miRNA, shared a large number of transcription factors with E-cadherin, and was involved in inflammatory differentiation regulation. In vivo experiments confirmed that SSP accelerated apoptosis, slowed down proliferation, inhibited inflammatory differentiation and IL-6, IL-1β, and TNF-α secretion in BMDCs, and decreased miR-505–3p, CDH1, and E-cadherin levels. After knocking down miR-505–3p, SSP could not regulate the inflammatory differentiation and IL-6, IL-1β, TNF-α level in BMDCs. Additionally, evodiamine was found and verified to be the key active ingredient of SSP in preventing the inflammatory differatiation of DCs. ConclusionSSP prevented the inflammatory differentiation of DCs by downregulating the expression of miR-505–3p, in which Evodiamine may played a key role.

The Role of TGF-β1 and Mutant SMAD4 on Epithelial-Mesenchymal Transition Features in Head and Neck Squamous Cell Carcinoma Cell Lines.

The aim of the present study was to investigate possible differences in the sensitivity of HNSCC cells to known EMT regulators. Three HNSCC cell lines (UM-SCC-1, -3, -22B) and the HaCaT control keratinocyte cell line were exposed to transforming growth factor beta 1 (TGF-β1), a known EMT master regulator, and the cellular response was evaluated by real-time cell analysis (RTCA), Western blot, quantitative PCR, flow cytometry, immunocytochemistry, and the wound closure (scratch) assay. Targeted sequencing on 50 cancer-related genes was performed using the Cancer Hotspot Panel v2. Mutant, and wild type SMAD4 cDNA was used to generate recombinant SMAD4 constructs for expression in mammalian cell lines. The most extensive response to TGF-β1, such as cell growth and migration, β-actin expression, or E-cadherin (CDH1) downregulation, was seen in cells with a more epithelial phenotype. Lower response correlated with higher basal p-TGFβ RII (Tyr424) levels, pointing to a possible autocrine pre-activation of these cell lines. Targeted sequencing revealed a homozygous SMAD4 mutation in the UM-SCC-22B cell line. Furthermore, PCR cloning of SMAD4 cDNA from the same cell line revealed an additional SMAD4 transcript with a 14 bp insertion mutation, which gives rise to a truncated SMAD4 protein. Overexpression of this mutant SMAD4 protein in the highly epithelial control cell line HaCaT resulted in upregulation of TGF-β1 and vimentin. Consistent with previous reports, the invasive and metastatic potential of HNSCC tumor cells appears associated with the level of autocrine secretion of EMT regulators such as TGF-β1, and it could be influenced by exogenous EMT cytokines such as those derived from immune cells of the tumor microenvironment. Furthermore, mutant SMAD4 appears to be a significant contributor to the mesenchymal transformation of HNSCC cells.

Di(2-ethylhexyl) phthalate exposure aggravates hypoxia/reoxygenation injury in cerebral endothelial cells by downregulating epithelial cadherin expression.

Di-(2-ethylhexyl) phthalate (DEHP) is a widely used plasticizer that has adverse health effects. Most phthalates exhibit reproductive toxicity and are associated with diseases such as cardiovascular disorders. However, the effect of DEHP exposure on acute hypoxia/reperfusion injury remains unknown. Therefore, we assessed whether hypoxia/reperfusion injury is aggravated by exposure to DEHP and investigated plausible underlying mechanisms, including oxidative stress and expression of cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) and endothelial junctional proteins. bEnd.3 cells were exposed to DEHP and subsequently subjected to oxygen-glucose deprivation (OGD). Cell viability was analyzed using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) proliferation assay. The effect of DEHP/OGD/reoxygenation (R) was evaluated by assessing the levels of NO, reactive oxygen species (ROS), and PGE2. The expression of COX-2, cleaved caspase-3, cleaved PARP, inducible nitric oxide synthase (iNOS), and the endothelial tight junction proteins claudin-5 and ZO-1 was evaluated using quantitative polymerase chain reaction and western blotting. OGD/R decreased cell viability, and DEHP exposure before OGD/R further aggravated cell viability. DEHP/OGD/R significantly increased NO, PGE2, and ROS production following OGD/R. In the DEHP/OGD/R group, iNOS, COX-2, cleaved caspase-3, and cleaved PARP expression increased, and claudin-5 and ZO-1 levels decreased compared with those in the OGD/R group. E-Cadherin expression decreased significantly after DEHP/OGD/R exposure compared with that after OGD/R; this decrease in expression was recovered by treatment with the COX-2 inhibitor indomethacin and antioxidant N-acetylcysteine. Exposure to DEHP exacerbated hypoxia-reoxygenation injury. The enhanced damage upon DEHP exposure was associated with increased oxidative stress and COX-2 expression, leading to E-cadherin downregulation and increased apoptosis.

The highly metastatic 4T1 breast carcinoma model possesses features of a hybrid epithelial/mesenchymal phenotype.

Epithelial-mesenchymal transitions (EMTs) are thought to promote metastasis via downregulation of E-cadherin (also known as Cdh1) and upregulation of mesenchymal markers such as N-cadherin (Cdh2) and vimentin (Vim). Contrary to this, E-cadherin is retained in many invasive carcinomas and promotes collective cell invasion. To investigate how E-cadherin regulates metastasis, we examined the highly metastatic, E-cadherin-positive murine 4T1 breast cancer model, together with the less metastatic, 4T1-related cell lines 4T07, 168FARN and 67NR. We found that 4T1 cells display a hybrid epithelial/mesenchymal phenotype with co-expression of epithelial and mesenchymal markers, whereas 4T07, 168FARN, and 67NR cells display progressively more mesenchymal phenotypes in vitro that relate inversely to their metastatic capacity in vivo. Using RNA interference and constitutive expression, we demonstrate that the expression level of E-cadherin does not determine 4T1 or 4T07 cell metastatic capacity in mice. Mechanistically, 4T1 cells possess highly dynamic, unstable cell-cell junctions and can undergo collective invasion without E-cadherin downregulation. However, 4T1 orthotopic tumors in vivo also contain subregions of EMT-like loss of E-cadherin. Thus, 4T1 cells function as a model for carcinomas with a hybrid epithelial/mesenchymal phenotype that promotes invasion and metastasis.