Zinc Finger E-box Binding Homeobox Research Articles

A Case Study of a High-Grade Serous Carcinoma of the Fallopian Tube Transformed into Carcinosarcoma at the Site of Peritoneal Dissemination With Immunohistological Evidence of an Epithelial-Mesenchymal Transition.

We report a patient in whom a primary high-grade serous carcinoma (HGSC) of the fallopian tube transformed into a carcinosarcoma at the site of peritoneal dissemination, and immunohistological analysis suggested the involvement of an epithelial-mesenchymal transition (EMT). The patient, a 70-year-old woman, had an abdominal mass palpated on admission, and a laparotomy was performed after a close examination. The resected right fallopian tube was cystically dilated, and a solid mass was observed in its lumen. The histological diagnosis was HGSC of the right fallopian tube with a papillary or complex tubular structure composed of tumor cells with marked nuclear irregularities. p53 was overexpressed, and no mesenchymal tumor component was observed. The resected left-sided abdominal mass of the omentum was a solid with a long diameter of 100 mm. Microscopically, the tumor exhibited a mixture of HGSC and high-grade sarcoma with nonspecific differentiation. Furthermore, a heterologous chondrosarcoma was subsequently observed from the high-grade sarcoma. The HGSC component was E-cadherin positive. The high-grade sarcoma component was positive for EMT-related proteins such as zinc finger E-box-binding homeobox 1 (ZEB1) and twist family bHLH transcription factor 1 (TWIST1). The chondrosarcoma component was ZEB1 positive and TWIST1 negative. p53 overexpression was found in all 3 components. The tumor of the omentum suggested that an EMT phenomenon was involved in the tumorigenesis. In this scenario, the primary HGSC of the fallopian tube with obvious invasion demonstrated that the conversion from carcinoma to sarcoma by EMT occurs only with peritoneal dissemination.

CAFs-derived TIAM1 Promotes OSCC Cell Growth and Metastasis by Regulating ZEB2.

Previous studies have suggested that cancer-associated fibroblasts (CAFs) within the tumor microenvironment are a critical factor in tumorigenesis and tumor development. However, the regulatory mechanisms of CAFs on oral squamous cell carcinoma (OSCC) are poorly defined. A CAF-conditioned medium (CAF-CM) was collected and applied to culture OSCC cells. Then, cell viability, proliferation, migration, and invasion were evaluated using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), 5-ethynyl-2'-deoxyuridine (EdU), Transwell, and scratch healing assays. T-Lymphoma Invasion and Metastasis 1 (TIAM1), zinc finger E-box-binding homeobox 2 (ZEB2), E-cadherin, and increased N-cadherin protein levels were determined using western blot. TIAM1 and ZEB2 mRNA levels were measured using real-time quantitative polymerase chain reaction (RT-qPCR). Their interaction was analyzed using Co-immunoprecipitation (Co-IP) assay. SCC25 cells with or without (TIAM1-silencing) CAFs were subcutaneously inoculated in nude mice to assess the effect of TIAM1 in CAFs on OSCC tumor growth in vivo. CAFs expedited OSCC cell proliferation, migration, invasion, and EMT. TIAM1 and ZEB2 expression were upregulated in OSCC patients and OSCC cells, and the TIAM1 level was much higher in CAFs than in OSCC cells. Furthermore, TIAM1 knockdown in CAFs might partly abolish the promotion of CAFs on OSCC cell development, implying that TIAM1 might be secreted by CAFs into the culture medium to exert its effects inside OSCCs. TIAM1 might increase ZEB2 expression, and ZEB2 upregulation might partly reverse the repression of TIAM1 silencing in CAFs on OSCC cell malignant behaviors. In vivo studies confirmed that CAFs accelerated OSCC tumor growth, these effects were partially counteracted by TIAM1 downregulation. Overall, TIAM1 secreted by CAFs could expedite OSCC cell growth and metastasis by regulating ZEB2, providing a promising therapeutic target for OSCC treatment.

ZEB1 inhibits LHβ subunit transcription when over-expressed, but is dispensable for LH synthesis in mice.

Luteinizing hormone (LH), a heterodimeric glycoprotein produced by pituitary gonadotrope cells, regulates gonadal function. Hypothalamic gonadotropin-releasing hormone (GnRH) stimulates LH synthesis and secretion. GnRH induces LHβ subunit (Lhb) expression via the transcription factor, early growth response 1 (EGR1), acting on the Lhb promoter. In contrast, over-expression of zinc finger E-box binding homeobox 1 (ZEB1) represses LH production in mice, but the underlying mechanism was not previously elucidated. Here, we observed that ZEB1 inhibited GnRH-stimulated, but not basal Lhb mRNA expression in homologous murine LβT2 cells. Moreover, ZEB1 blocked GnRH and/or EGR1 induction of murine Lhb, but not human LHB promoter-reporter activity in these cells. Using chimeric reporters, we mapped the species-specific ZEB1 sensitivity to sequence differences, including in Z- and E-boxes, in the proximal Lhb/LHB promoters, immediately upstream of the transcription start sites. ZEB1 bound to the murine Lhb promoter with higher affinity than to the human LHB promoter in this region. To examine ZEB1's physiological role in LH synthesis, we characterized gonadotrope-specific Zeb1 knockout mice. Loss of ZEB1 in gonadotropes did not affect LH production or secretion. Collectively, the data suggest that ZEB1, when over-expressed, can inhibit GnRH/EGR1 induction of murine Lhb transcription but does not play a necessary role in LH synthesis in mice.

ZEB1 Promotes Epithelial-Mesenchymal Transition of Endometrial Epithelial Cells and Plays a Critical Role in Embryo Implantation in Mice.

Zinc finger E-box binding homeobox 1 (ZEB1) promotes epithelial-mesenchymal transition (EMT) in carcinogenesis, but its role in embryo implantation has not yet been well studied. In the present study we evaluated the hypothesis that ZEB1-induced EMT is essential for embryo implantation in vivo. Endometrial epithelium from female Kunming mice (non-pregnant, and pregnant from day 2.5 to 6.5) were collected for assessment of mRNA/protein expression of ZEB1, and EMT markers E-cadherin and vimentin, by employment of real-time quantitative reverse transcription PCR, Western blot, and immunohistochemical staining. To test if knockdown of ZEB1 affects embryo implantation in vivo, mice received intrauterine injection of shZEB1 before the number of embryos implanted was counted. The results showed that, ZEB1 was highly expressed at both mRNA and protein levels in the mouse endometrium on day 4.5 of pregnancy, paralleled with down-regulated E-cadherin and up-regulated vimentin expression (P < 0.05). Intrauterine injection of shZEB1 markedly suppressed embryo implantation in mice (P < 0.01). Conclusively, the present work demonstrated that ZEB1 is essential for embryo implantation under in vivo condition, and is possibly due to its effect on modulation of endometrial receptivity through EMT.

USP7 deubiquitinates epigenetic reader ZMYND8 to promote breast cancer cell migration and invasion

The ubiquitin-proteasome system (UPS), which involves E3 ligases and deubiquitinases (DUBs), is critical for protein homeostasis. The epigenetic reader ZMYND8 (zinc finger MYND-type containing 8) has emerged as an oncoprotein, and its protein levels are elevated in various types of cancer, including breast cancer. However, the mechanism by which ZMYND8 protein levels are increased in cancer remains elusive. Although ZMYND8 has been reported to be regulated by the E3 ligase FBXW7, it is still unknown whether ZMYND8 could be modulated by DUBs. Here, we identified USP7 (ubiquitin carboxyl-terminal hydrolase 7) as a bona fide DUB for ZMYND8. Mechanically, USP7 directly binds to the PBP (PHD-BRD-PWWP) domain of ZMYND8 via its TRAF (tumor necrosis factor receptor-associated factor) domain and UBL (ubiquitin-like) domain and removes F-box and WD repeat domain containing 7 (FBXW7)-catalyzed poly-ubiquitin chains on lysine residue 1034 (K1034) within ZMYND8, thereby stabilizing ZMYND8 and stimulating the transcription of ZMYND8 target genes ZEB1 (zinc finger E-box binding homeobox 1) and VEGFA (Vascular Endothelial Growth Factor A). Consequently, USP7 enhances the capacity of breast cancer cells for migration and invasion through antagonizing FBXW7-mediated ZMYND8 degradation. Importantly, the protein levels of USP7 positively correlates with those of ZMYND8 in breast cancer tissues. These findings delineate an important layer of migration and invasion regulation by the USP7-ZMYND8 axis in breast cancer cells.

Effects of berberine hydrochloride on antioxidant response and gut microflora in the Charybdis japonica infected with Aeromonas hydrophila

This study used berberine hydrochloride to treat the Asian paddle crab, Charybdis japonica infected with the Gram-negative bacterium Aeromonas hydrophila at concentrations of 0, 100, 200 and 300 mg/L. The effect of berberine hydrochloride on the survival rate and gut microbiota of C. japonica was investigated. Berberine hydrochloride improved the stability of the intestinal flora, with an increase in the abundance of probiotic species and a decrease in the abundance of both pathogenic bacteria after treatment with high concentrations of berberine hydrochloride. Berberine hydrochloride altered peroxidase activity (POD), malondialdehyde (MDA), and lipid peroxidation (LPO) in the intestinal tract compared to the control. Berberine hydrochloride could modulate the energy released from the enzyme activities of hexokinase (HK), phosphofructokinase (PFK), and pyruvate kinase (PK) in the intestinal tract of C. japonica infected with A. hydrophila. Zona occludens 1 (ZO-1), Zinc finger E-box binding homeobox 1 (ZEB1), occludin and signal transducer, and activator of transcription5b (STAT5b) expression were also increased, which improved intestinal barrier function. The results of this study provide new insights into the role of berberine hydrochloride in intestinal immune mechanisms and oxidative stress in crustaceans.

Lowering expression of Epsin-3 inhibits migration and invasion of lung adenocarcinoma cells by inhibiting the epithelial–mesenchymal transition

The epithelial–mesenchymal transition (EMT) is a genetic reprogramming that tumor cells utilize for metastasis. Epsin-3 (EPN3) is an endocytic adapter protein involved in clathrin-mediated endocytosis and had been previously linked to EMT in breast cancer and glioma metastasis. In this study, identified the role of epsin-3 in lung adenocarcinoma and metastasis and epsin-3 levels identified using an expression profile analysis of patient data indicated the protein was abnormally overexpressed in lung adenocarcinoma patients and this was directly linked to disease severity. Gene knockdowns of EPN3 in human adenocarcinoma cell line A549 and the non-small cell lung carcinoma cell line H1299 decreased the levels of mesenchymal markers, including vimentin (VIM), N-cadherin (NCAD) and embryonic transcription factors like zinc finger E-box binding homeobox 1(ZEB1), snail, and the key molecules of Wnt pathway such as β-catenin and resulted in increased expression of the epithelial marker E-cadherin (ECAD). Our data links EPN3 to the EMT process in lung cancer and inhibition of its expression reduced the metastatic and invasive ability of lung adenocarcinoma cells by inhibiting the EMT process.

Utilising deep learning networks to classify ZEB2 expression images in cervical cancer.

Aims/Background Cervical cancer continues to be a significant cause of cancer-related deaths among women, especially in low-resource settings where screening and follow-up care are lacking. The transcription factor zinc finger E-box-binding homeobox 2 (ZEB2) has been identified as a potential marker for tumour aggressiveness and cancer progression in cervical cancer tissues. Methods This study presents a hybrid deep learning system developed to classify cervical cancer images based on ZEB2 expression. The system integrates multiple convolutional neural network models-EfficientNet, DenseNet, and InceptionNet-using ensemble voting. We utilised the gradient-weighted class activation mapping (Grad-CAM) visualisation technique to improve the interpretability of the decisions made by the convolutional neural networks. The dataset consisted of 649 annotated images, which were divided into training, validation, and testing sets. Results The hybrid model exhibited a high classification accuracy of 94.4% on the test set. The Grad-CAM visualisations offered insights into the model's decision-making process, emphasising the image regions crucial for classifying ZEB2 expression levels. Conclusion The proposed hybrid deep learning model presents an effective and interpretable method for the classification of cervical cancer based on ZEB2 expression. This approach holds the potential to substantially aid in early diagnosis, thereby potentially enhancing patient outcomes and mitigating healthcare costs. Future endeavours will concentrate on enhancing the model's accuracy and investigating its applicability to other cancer types.

Phosphocreatine Promotes Epigenetic Reprogramming to Facilitate Glioblastoma Growth Through Stabilizing BRD2.

Glioblastoma (GBM) exhibits profound metabolic plasticity for survival and therapeutic resistance, while the underlying mechanisms remain unclear. Here, we show that GBM stem cells reprogram the epigenetic landscape by producing substantial amounts of phosphocreatine (PCr). This production is attributed to the elevated transcription of brain-type creatine kinase, mediated by Zinc finger E-box binding homeobox 1. PCr inhibits the poly-ubiquitination of the chromatin regulator bromodomain containing protein 2 (BRD2) by outcompeting the E3 ubiquitin ligase SPOP for BRD2 binding. Pharmacological disruption of PCr biosynthesis by cyclocreatine (cCr) leads to BRD2 degradation and a decrease in its targets' transcription, which inhibits chromosome segregation and cell proliferation. Notably, cyclocreatine treatment significantly impedes tumor growth and sensitizes tumors to a BRD2 inhibitor in mouse GBM models without detectable side effects. These findings highlight that high production of PCr is a druggable metabolic feature of GBM and a promising therapeutic target for GBM treatment. Significance: Glioblastoma (GBM) exhibits an adaptable metabolism crucial for survival and therapy resistance. We demonstrate that GBM stem cells modify their epigenetics by producing phosphocreatine (PCr), which prevents bromodomain containing protein 2 (BRD2) degradation and promotes accurate chromosome segregation. Disrupting PCr biosynthesis impedes tumor growth and improves the efficacy of BRD2 inhibitors in mouse GBM models.

A distinct subset of urothelial cells with enhanced EMT features promotes chemotherapy resistance and cancer recurrence by increasing COL4A1-ITGB1 mediated angiogenesis

Drug resistance and tumor recurrence remain clinical challenges in the treatment of urothelial carcinoma (UC). However, the underlying mechanism is not fully understood. Here, we performed single-cell RNA sequencing and identified a subset of urothelial cells with epithelial-mesenchymal transition (EMT) features (EMT-UC), which is significantly correlated with chemotherapy resistance and cancer recurrence. To validate the clinical significance of EMT-UC, we constructed EMT-UC like cells by introducing overexpression of two markers, Zinc Finger E-Box Binding Homeobox 1 (ZEB1) and Desmin (DES), and examined their histological distribution characteristics and malignant phenotypes. EMT-UC like cells were mainly enriched in UC tissues from patients with adverse prognosis and exhibited significantly elevated EMT, migration and gemcitabine tolerance in vitro. However, EMT-UC was not specifically identified from tumorous tissues, certain proportion of them were also identified in adjacent normal tissues. Tumorous EMT-UC highly expressed genes involved in malignant behaviors and exhibited adverse prognosis. Additionally, tumorous EMT-UC was associated with remodeled tumor microenvironment (TME), which exhibited high angiogenic and immunosuppressive potentials compared with the normal counterparts. Furthermore, a specific interaction of COL4A1 and ITGB1 was identified to be highly enriched in tumorous EMT-UC, and in the endothelial component. Targeting the interaction of COL4A1 and ITGB1 with specific antibodies significantly suppressed tumorous angiogenesis and alleviated gemcitabine resistance of UC. Overall, our findings demonstrated that the driven force of chemotherapy resistance and recurrence of UC was EMT-UC mediated COL4A1-ITGB1 interaction, providing a potential target for future UC treatment.

Endothelial cell specific molecule 1 promotes epithelial-mesenchymal transition of cervical cancer via the E-box binding homeobox 1.

To investigate the mechanism of endothelial cell specific molecule 1 (ESM1) promoting cervical cancer cell proliferation and EMT characteristics through zinc finger E-box binding homeobox 1 (ZEB1)/EMT pathway. The correlation between ESM1 expression and prognosis of cervical cancer patients was analyzed by bioinformatics. SiHa, HeLa cell lines and corresponding control cell lines with stable ESM1 expression were obtained. Cell proliferation ability was detected by CCK-8 assay. The invasion and migration ability of Hela and SiHa cells were detected by Transwell assay and scratch closure assay. Expressions of EMT-related markers E-cadherin and Vimentin were detected by real-time PCR. The ability of silenced ESM1 to tumor formation in vivo was detected by tumor formation in nude mice. The effects of aloe-emodin on inhibit ESM1 expression and its inhibitory effect on cervical cancer cells in vitro and in vivo were analyzed by the same method. ESM1 was highly expressed in cervical cancer, and the high expression of ESM1 was associated with poor prognosis of cervical cancer patients. CCK-8 results showed that the proliferation, invasion and migration of Hela and SiHa cells were significantly reduced after siRNA interfered with ESM1 expression. Overexpression of ESM1 promoted the proliferation and migration of cervical cancer cells. Mechanism studies have shown that the oncogenic effect of ESM1 is realized through the ZEB1/PI3K/AKT pathway. High throughput drug screening found that aloe-emodin can target ESM1. Inhibitory effect of aloe emodin on ESM1/ZEB1/EMT signaling pathway and cervical cancer cells. The silencing of ESM1 expression may inhibit the proliferation, invasion, metastasis and epithelial-mesenchymal transformation of cervical cancer cells by inhibiting ZEB1/PI3K/AKT. Aloe-emodin is a potential treatment for cervical cancer, which can play an anti-tumor role by inhibiting ESM1/ZEB1.

N6-methyladenosine triggers renal fibrosis via enhancing translation and stability of ZEB2 mRNA

In recent years, a surge in studies investigating N6-methyladenosine (m6A) modification in human diseases has occurred. However, the specific roles and mechanisms of m6A in kidney disease remain incompletely understood. This study revealed that m6A plays a positive role in regulating renal fibrosis (RF) by inducing epithelial-to-mesenchymal phenotypic transition (EMT) in renal tubular cells. Through comprehensive analyses, including m6A sequencing, RNA sequencing, and functional studies, we confirmed the pivotal involvement of zinc finger E-box binding homeobox 2 (ZEB2) in m6A-mediated RF and EMT. Notably, the m6A-modified coding sequence (CDS) of ZEB2 mRNA significantly enhances its translational elongation and mRNA stability by interacting with the YTHDF1/eEF-2 complex and IGF2BP3, respectively. Moreover, targeted demethylation of ZEB2 mRNA using the dm6ACRISPR system substantially decreases ZEB2 expression and disrupts the EMT process in renal tubular epithelial cells. In vivo and clinical data further support the positive influence of m6A/ZEB2 on RF progression. Our findings highlight the m6A-mediated regulation of RF through ZEB2, revealing a novel therapeutic target for RF treatment and enhancing our understanding of the impact of mRNA methylation on kidney disease.

MiR-200a-3p promotes the malignancy of endometrial carcinoma through negative regulation of epithelial-mesenchymal transition

BackgroundmiR-200a-3p is involved in the progression of malignant behavior in various tumors, and its mechanism of action in endometrial cancer is speculated to be related to epithelial-mesenchymal transition (EMT). Therefore, this study explored the metastatic mechanism of miR-200a-3p and EMT in endometrial cancer, with the aim of identifying potential therapeutic targets.MethodsqRT-PCR was used to analyze miR-200a-3p expression in HEC-1B and Ishikawa cell lines. The cell proliferation assay, transwell assay, and cell scratch test were used to assess changes in the malignant phenotypes of cells after regulating miR-200a-3p expression. Changes in EMT-related protein zinc finger E-box binding homeobox 1 (ZEB1) were detected after regulating miR-200a-3p expression. An endometrial carcinoma transplantation mouse tumor model was constructed, and multiple EMT-related proteins were examined.ResultsThe expression of miR-200a-3p and ZEB1 in the endometrial cancer cell lines was higher than in normal endometrial epithelial cell lines (P < 0.05). After silencing miR-200a-3p, the expression of EMT-related protein ZEB1 increased, indicating a negative correlation. Simultaneously, the proliferation, invasion, and metastasis of endometrial cancer cells were significantly enhanced. After miR-200a-3p overexpression, the corresponding malignant phenotype was reversed (P < 0.05). In in vivo experiments, the degree of tumor malignancy and the expression level of EMT-related proteins were significantly reduced in the miR-200a-3p mimic group (P < 0.05).ConclusionThis study found that miR-200a-3p is a promising target, regulating the EMT process and promoting endometrial cancer progression.

ZEB2 knockdown inhibits interleukin-1β-induced cartilage degradation and inflammatory response through the Wnt/β-catenin pathway in human chondrocytes

Objective Osteoarthritis (OA) is a degenerative disease of the joints characterized by inflammation and cartilage degeneration. Zinc finger E-box binding homeobox 2 (ZEB2) contains various function domains that interact with multiple transcription factors involved in various cellular functions. However, the function of ZEB2 in OA has not been clearly illustrated. Method Interleukin-1β (IL-1β) was used to establish an OA model in vitro. We quantified the ZEB2 expression in cartilage tissues from OA patients and IL-1β-induced chondrocytes through reverse transcription–quantitative polymerase chain reaction and Western blot. We then used functional assays to explore the function of ZEB2 during OA progression. Results ZEB2 expression was increased in OA cartilage tissues and chondrocytes. The silencing of ZEB2 increased aggrecan and collagen II levels, and reduced the content of matrix metalloproteinase-3 (MMP-3), MMP-9, and MMP-13. ZEB2 knockdown inhibited the effects of IL-1β on the production of nitric oxide and prostaglandin E2, and the expression of inducible nitric oxide synthase and cyclooxygenase-2. ZEB2 inhibition also suppressed the levels of IL-6 and tumour necrosis factor-α, and increased the IL-10 level in IL-1β-treated cells. Mechanically, ZEB2 knockdown blocked the activation of the Wnt/β-catenin pathway in chondrocytes. Conclusion Knockdown of ZEB2 alleviated IL-1β-induced cartilage degradation and the inflammatory response through the Wnt/β-catenin pathway in chondrocytes.

Evaluation of molecular effects associated with apoptosis, tumour progression, angiogenesis and metastasis by a novel combination of drugs with ormeloxifene in triple negative breast cancer cells.

To investigate the molecular effects of a novel combination [sertraline and plumbagin (comb) with ormeloxifene (Orm)] for anticancer activity in triple negative breast cancer cell line "MDA-MB-231". The cytotoxic effect of the drugs was analyzed by the MTT assay and nuclear morphological changes by acridine orange/ethidium bromide (AO/EB) staining. Induction of apoptosis by annexin V-FITC staining, active caspase-3 detection and cell cycle analysis were studied in vitro on "MDA-MB-231" cells. The qRT-PCR was done to explore the upregulation and down regulation of targeted genes for angiogenesis, metastasis, tumor suppression and protein folding on the triple negative breast cancer cells. The preliminary anti-angiogenic effect of the drugs was assessed by chorioallantoic membrane (CAM) assay. Orm showed inhibitory effects in "MDA-MB-231" cells in a dose and time dependent manner whereas; the drugs in combination gave better cytotoxic effects in the screening MTT assay. Orm + comb was more effective than Orm alone in eliciting apoptosis as well as inhibited the single cell to grow into a colony. CAM assay using Orm and Orm + comb suggested the anti-angiogenic potential which was further confirmed by the downregulation of VEGF in "MDA-MB-231" cells by qRT-PCR studies. The combination was found to effectively upregulate the expression of P53 and P21 and downregulate the gene expression of zinc finger E-box binding homeobox 1 (ZEB1) and heat shock protein 70 (HSP70) in "MDA-MB-231" cancer cells. Collectively this study reveals the efficacy of Orm + comb as more significant than the clinically used tamoxifen (Tam). The study elucidates the promising novelty of the combination as a potential chemotherapeutic intervention for mitigating the aggressiveness of triple negative breast cancer and it addresses the intrinsic resistance caused by single drug treatments.

MiR-150-5p Alleviates Renal Tubule Epithelial Cell Fibrosis via the Inhibition of Epithelial-Mesenchymal Transition by Targeting ZEB1

Introduction: Although microRNA (miR)-150-5p participates in the progression of renal fibrosis, its mechanism of action remains elusive. Methods: A mouse model of unilateral ureteral obstruction was used. The in vitro renal fibrosis model was established by stimulating human kidney 2 (HK-2) cells with transforming growth factor beta 1 (TGF-β1). The expression profiles of miR-150-5p, zinc finger E-box binding homeobox 1 (ZEB1), and other fibrosis- and epithelial-mesenchymal transition (EMT)-linked proteins were determined using Western blot and quantitative reverse transcription polymerase chain reaction. The relationship between miR-150-5p and ZEB1 in HK-2 cells was confirmed by a dual-luciferase reporter assay. Results: Both in vivo and in vitro renal fibrosis models revealed reduced miR-150-5p expression and elevated ZEB1 level. A significant decrease in E-cadherin levels, as well as increases in alpha smooth muscle actin (α-SMA) and collagen type I (Col-I) levels, was seen in TGF-β1-treated HK-2 cells. The overexpression of miR-150-5p ameliorated TGF-β1-mediated fibrosis and EMT. Notably, miR-150-5p acts by directly targeting ZEB1. A significant reversal of the inhibitory impact of miR-150-5p on TGF-β1-mediated fibrosis and EMT in HK-2 cells was observed upon ZEB1 overexpression. Conclusion: MiR-150-5p suppresses TGF-β1-induced fibrosis and EMT by targeting ZEB1 in HK-2 cells, providing helpful insights into the therapeutic intervention of renal fibrosis.

Abstract PR002: Sarcomatoid Histological Variants of Canine Muscle-Invasive Bladder Cancer: Transcription Factor Activation Highlights Pathways of Epithelial-Mesenchymal Transformation Similar to Humans

Abstract The histologic heterogeneity of human Muscle Invasive Bladder Cancer (MIBC) is one of the main contributing factors to poor treatment outcomes. Recent reports on MIBC histological variants have highlighted increased levels of transcription factors (TF) associated with epithelial-mesenchymal transformation (EMT) and epigenetic regulation in the sarcomatoid histology variant of MIBC. Dogs with spontaneously developing MIBC have been shown to display similar histological and molecular features, in addition to closely mimicking the clinical behavior of human MIBC. Here, we add to previously reported data on histological variants in canine MIBC by evaluating 21 tumor biopsies for variant histology and performing bulk RNAseq analyses on 3 organoid cell lines derived from one sarcomatoid subvariant and two conventional urothelial carcinoma (UC). MIBC biopsies from 21 dogs were reviewed for variant histology by a human urologic pathologist. Organoids derived from the urine of canine MIBC patients were cultured, preserved in RNA later, and sequenced for mRNA expression to identify TF associated with sarcomatoid variants versus conventional UC. All canine MIBC biopsies were classified as invasive, high-grade UC. Histologic variants were identified as glandular differentiation in 7/21, sarcomatoid differentiation in 3/21, squamous differentiation in 3/21, micropapillary carcinoma in 1/21 MIBC samples and small nested variants in 1/21 samples; with the rest of the tumors classified as conventional UC. Raw RNAseq analyses revealed no clear clustering of expression profiles between the three organoid cell lines, indicating distinct RNA expression profiles between the sarcomatoid variants and conventional UC of canine MIBC. To evaluate differences in the expression of TF targets between the organoid cell lines, pathway analyses and VIPER algorithms were used. Organoids derived from sarcomatoid variant UC showed increased expression of Snail familiy transcription repressor 1 (SNAI1) along with decreased expression of cadherin 1 (CDH1), indicating a signature of EMT, similar to that previously identified in human MIBC organoids with sarcomatoid variant histology. Canine MIBC organoids derived from conventional UC histology samples showed a TF profile associated with proliferation, metastasis, and progression, such as increased Zinc finger E-box binding homeobox 1 (ZEB1), E2F transcription factor 3 (E2F3), and centromere protein F (CENPF), as previously described in humans with high grade, invasive UC. In conclusion, the frequency of some histologic variants in canine MIBC, such as sarcomatoid UC, appear to be higher than reported in human patients. TF analyses of canine MIBC-derived organoid cell lines showed evidence of EMT, similar to the sarcomatoid variants of MIBC in humans. Organoids derived from canine MIBC could potentially serve as a valuable model for evaluating the efficacy of novel treatment modalities for the rare histologic variants of UC. Citation Format: Karin Allenspach, Mohamed Elbadawy, Hannah Nocholson, Christopher Zdyrski, John Cheville, Eugene Douglass, Elizabeth W. Howerth, Lilian Oliveira, Jonathan P. Mochel. Sarcomatoid Histological Variants of Canine Muscle-Invasive Bladder Cancer: Transcription Factor Activation Highlights Pathways of Epithelial-Mesenchymal Transformation Similar to Humans [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr PR002.

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.

Hypoxia-inducible factor 3α1 increases epithelial-to-mesenchymal transition and iron uptake to drive colorectal cancer liver metastasis.

Hypoxia-inducible factor (HIF)-3α1's role in colorectal cancer (CRC) cells, especially its effects on epithelial-mesenchymal transition (EMT), zinc finger E-box binding homeobox 2 (ZEB2) gene expression, and iron metabolism, remains largely unstudied. This research sought to elucidate these relationships. RNA-seq was conducted to investigate the impact of HIF-3α1 overexpression in CRC cells. Dual-luciferase reporter assays assessed the direct targeting of ZEB2 by HIF-3α1. Scratch assays measured changes in cell migration following HIF-3α1 overexpression and ZEB2 knockdown. The effects of HIF-3α1 overexpression on colon tumour growth and liver metastasis were examined in vivo. Iron chelation was used to explore the role of iron metabolism in HIF-3α1-mediated EMT and tumour growth. HIF-3α1 overexpression induced EMT and upregulated ZEB2 expression, enhancing cancer cell migration. ZEB2 knockdown reduced mesenchymal markers and cell migration. HIF-3α1 promoted colon tumour growth and liver metastasis, increased transferrin receptor (TFRC) expression and cellular iron levels, and downregulated HIF-1α, HIF-2α, and NDRG1. Iron chelation mitigated HIF-3α1-mediated EMT, tumour growth, and survival. HIF-3α1 plays a critical role in colon cancer progression by promoting EMT, iron accumulation, and metastasis through ZEB2 and TFRC regulation, suggesting potential therapeutic targets in CRC.

LncRNA-SERB promotes vasculogenic mimicry (VM) formation and tumor metastasis in renal cell carcinoma

A growing body of evidence shows that vasculogenic mimicry (VM) is closely related to the invasion and metastasis of many tumor cells. Although the estrogen receptor (ER) can promote initiation and progression of renal cell carcinoma (RCC), how the downstream biomolecules are involved, and the detailed mechanisms of how ER expression is elevated in RCC remain to be further elucidated. Here, we discovered that long noncoding RNA (LncRNA)-SERB is highly expressed in tumor cells of RCC patients. We used multiple RCC cells and an invivo mouse model for our study, and results indicated that LncRNA-SERB could boost RCC VM formation and cell invasion invitro and invivo. Although a previous report showed that ERβ can affect the VM formation in RCC, it is unclear which factor could upregulate ERβ. This is the first study to show LncRNA-SERB can be the upstream regulator of ERβ to control RCC progression. Mechanistically, LncRNA-SERB may increase ERβ via binding to the promoter area, and ERβ functions through transcriptional regulation of zinc finger E-box binding homeobox 1 (ZEB1) to regulate VM formation. These results suggest that LncRNA-SERB promotes RCC cell VM formation and invasion by upregulating the ERβ/ZEB1 axis and that therapeutic targeting of this newly identified pathway may better inhibit RCC progression.