Targeting Epithelial-mesenchymal Transition Research Articles

Whole transcriptome analysis to reveal epithelial-mesenchymal transition after neoadjuvant therapy with or without additional anti-EGFR treatment: Subgroup analysis of esophageal squamous cell carcinomas of the SAKK 75/08 and the EORTC AIO POWER study.

4071 Background: In localized disease of esophageal squamous cell cancer (ESCC), a trend in higher pathological response rates and longer time to treatment failure was seen by addition of anti-EGFR treatment to radio-chemotherapy (RCTX) compared to RCTX alone (SAKK 75/08 trial and others). On the contrary, the effect of anti-EGFR treatment to chemotherapy (CTX) remains unclear as no survival benefit was detected within advanced patients (EORTC-AIO-POWER study). Since perfect discrimination and selection of subgroups with highest benefit for anti-EGFR treatment (AB) is missing, we investigated the predictive values of whole transcriptomic gene expression analysis (WTGE) applied on biopsy tissue. Methods: 50 pretherapeutic formalin fixed paraffin embedded specimens of ESCC patients from SAKK 75/08 study were analyzed for the effect of RCTX with and without anti-EGFR AB. As well as 26 historic controls of primary resected tumor stage equally distributed ESCC were analyzed. For the advanced setting, we analyzed 28 additional pretherapeutic biopsies and compared groups from CTX to CTX plus AB. The HTG EdgeSeq method was used for NGS-based WTGE. Response to treatment was assessed by histopathological tumor regression in localized disease and clinical courses. Response to treatment in the advanced tumor setting was assessed to the clinical course of stable disease and partial response versus non-responders. Results: Firstly, NGS-based WTGE failed to show significant differences in expression patterns between responding and non-responding ESCC patients, irrespective of treatment protocols and EGFR AB in the localized as well in advanced disease setting. Secondly however, comparison between pre-treatment biopsies and posttreatment residual tumor tissues detected 781 genes that were upregulated and 623 that were downregulated with gene sets associated with muscle processes and epithelial-mesenchymal transition (EMT) in the localized disease. EMT genes were also enriched in residual tumors after neoadjuvant RCTX compared to primary resection in an independent control cohort. Additionally performed immunohistochemical studies showed lower numbers of ZEB-1 positive ESCC in an independent collection of tumors treated by neoadjuvant RCTX compared to primary resection. Conclusions: Our Whole transcriptomic gene expression analyses suggest that EMT is involved in responses to neoadjuvant protocols including EGFR targeting therapies. Targeting EMT may be a molecular pathway to increase complete responses after neoadjuvant RCTX in ESCC.

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.

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

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

Pyrroloquinoline quinone ameliorates PM2.5-induced pulmonary fibrosis through targeting epithelial-mesenchymal transition.

Pulmonary fibrosis is a lung disorder affecting the lungs that involves the overexpressed extracellular matrix, scarring and stiffening of tissue. The repair of lung tissue after injury relies heavily on Type II alveolar epithelial cells (AEII), and repeated damage to these cells is a crucial factor in the development of pulmonary fibrosis. Studies have demonstrated that chronic exposure to PM2.5, a form of air pollution, leads to an increase in the incidence and severity of pulmonary fibrosis by stimulation of epithelial-mesenchymal transition (EMT) in lung epithelial cells. Pyrroloquinoline quinone (PQQ) is a bioactive compound found naturally that exhibits potent anti-inflammatory and anti-oxidative properties. The mechanism by which PQQ prevents pulmonary fibrosis caused by exposure to PM2.5 through EMT has not been thoroughly discussed until now. In the current study, we discovered that PQQ successfully prevented PM2.5-induced pulmonary fibrosis by targeting EMT. The results indicated that PQQ was able to inhibit the expression of type I collagen, a well-known fibrosis marker, in AEII cells subjected to long-term PM2.5 exposure. We also found the alterations of cellular structure and EMT marker expression in AEII cells with PM2.5 incubation, which were reduced by PQQ treatment. Furthermore, prolonged exposure to PM2.5 considerably reduced cell migratory ability, but PQQ treatment helped in reducing it. Invivo animal experiments indicated that PQQ could reduce EMT markers and enhance pulmonary function. Overall, these results imply that PQQ might be useful in clinical settings to prevent pulmonary fibrosis.

Investigation of the Effects of PFKFB3 Small Molecule Inhibitor KAN0438757 on Cell Migration and Expression Level of N-cadherin Protein in Glioblastoma Cell Lines

PFKFB3 (6-phosphofructose-2-kinase/fructose-2,6-bisphosphatase 3) is a enzyme involved in glycolysis, the process by which cells convert glucose into energy. PFKFB3 is known to be overexpressed in many types of cancer, including glioblastoma, a highly aggressive brain tumour. The epithelial-mesenchymal transition (EMT) is a biological mechanism linked to cancer growth and enhanced invasion and metastasis. Inhibition of PFKFB3 in glioblastoma cells is seen as a potential therapeutic strategy to target EMT and inhibit cancer progression. Various small molecule PFKFB3 inhibitors have been created and tested in preclinical trials. The purpose of this study is to look into the possible effect of KAN0438757, a very efficient PFKB3 inhibitor, on glioblastoma cells. KAN0438757's impact on viability of cells, cell migration and cell death in glioblastoma cancer cell lines U373 and U251 were investigated by WST-1 Cell viability, AO/EtBr staining western blotting and wound healing-cell migration assays. Glioblastoma cells showed decreased cell viability and dose-dependent apoptotic morphological changes after KAN0438757 treatment. In addition, it was determined that N-cadherin protein level decreased and cell migration was suppressed. In conclusion, KAN0438757, a PFKFB3 inhibitor, can be considered as a valid approach to target cell death and EMT in glioblastoma cancer cell lines.

Downregulation of LPAR1 Promotes Invasive Behavior in Papillary Thyroid Carcinoma Cells.

Lysophosphatidic acid receptor 1 (LPAR1) has been identified as a biomarker in various cancer types. However, its biological function in papillary thyroid carcinoma (PTC) remains unknown. LPAR1 was identified as a key regulator of epithelial-mesenchymal transition (EMT) in PTC cells through bioinformatics analysis of TCGA and GEO datasets. PPI analysis and correlation with immune infiltrates were also conducted. LPAR1 expression was evaluated using Gepia2 and GTEx, and miRNA target gene prediction was done with multiMiR. To assess the expression of LPAR1, we extracted total RNA from both the BCPAP cell line and the normal human thyroid epithelial cell line Nthy-ori 3-1. The levels of LPAR1 expression were then measured using quantitative real-time polymerase chain reaction (qRT-PCR) in the BCPAP cell line, with a comparison to the Nthy-ori 3-1 cell line. 1081 genes were upregulated, and 544 were downregulated compared to normal tissue. LPAR1 was identified as a key candidate by analyzing the TCGA and GEO datasets. PPI data analysis showed interactions with metastasis-related proteins. Functional enrichment analysis indicated involvement in signaling pathways like phospholipase D and actin cytoskeleton regulation. LPAR1 expression correlated positively with immune infiltrates such as CD4+ T cells, macrophages, neutrophils, and myeloid dendritic cells but negatively with B cells. Additionally, miR-221-5p was predicted to target LPAR1 in PTC. Furthermore, our experimental data demonstrated that LPAR1 was under-expressed in the PTC cell line compared to the nonmalignant one (P < .01). LPAR1 suppresses metastasis and is linked to EMT, as evidenced by the decreased LPAR1 expression and increased miR-221-5p in PTC. This suggests its potential as a biomarker for diagnosis and prognosis and as a therapeutic target for EMT.

A novel patient-derived meningioma spheroid model as a tool to study and treat epithelial-to-mesenchymal transition (EMT) in meningiomas

Meningiomas are the most common intracranial brain tumours. These tumours are heterogeneous and encompass a wide spectrum of clinical aggressivity. Treatment options are limited to surgery and radiotherapy and have a risk of post-operative morbidities and radiation neurotoxicity, reflecting the need for new therapies. Three-dimensional (3D) patient-derived cell culture models have been shown to closely recapitulate in vivo tumour biology, including microenvironmental interactions and have emerged as a robust tool for drug development. Here, we established a novel easy-to-use 3D patient-derived meningioma spheroid model using a scaffold-free approach. Patient-derived meningioma spheroids were characterised and compared to patient tissues and traditional monolayer cultures by histology, genomics, and transcriptomics studies. Patient-derived meningioma spheroids closely recapitulated morphological and molecular features of matched patient tissues, including patient histology, genomic alterations, and components of the immune microenvironment, such as a CD68 + and CD163 + positive macrophage cell population. Comprehensive transcriptomic profiling revealed an increase in epithelial-to-mesenchymal transition (EMT) in meningioma spheroids compared to traditional monolayer cultures, confirming this model as a tool to elucidate EMT in meningioma. Therefore, as proof of concept study, we developed a treatment strategy to target EMT in meningioma. We found that combination therapy using the MER tyrosine kinase (MERTK) inhibitor UNC2025 and the histone deacetylase (HDAC) inhibitor Trichostatin A (TSA) effectively decreased meningioma spheroid viability and proliferation. Furthermore, we demonstrated this combination therapy significantly increased the expression of the epithelial marker E-cadherin and had a repressive effect on WHO grade 2-derived spheroid invasion, which is suggestive of a partial reversal of EMT in meningioma spheroids.

EMT transcription factors activated circuits: A novel tool to study EMT dynamics and its therapeutic implications

The epithelial mesenchymal transition (EMT) plays significant roles in the progression of cancer and fibrotic disease. Moreover, this process is reversible, resulting in mesenchymal epithelial transition (MET), which plays an important role in cancer metastasis. There is a lack of methods to trace and target EMT cells using synthetic biology circuits, which makes it difficult to study the cell fate or develop targeted treatments. In this study, we introduced responsive EMT sensing circuits, which sense the EMT using specific promoters that respond to transcription factors typical of EMT activation (EMT-TFs). The transcriptional strength of EMT-sensing promoters decreased more than 13-fold in response to the overexpression of the EMT-TF. Then, the NOT gate circuits were built by placing the tetR transcription repressor under the control of EMT sensing promoters and expressed an output signal using the constitutive CMV promoter modified with tetO sites This circuit is named EMT sensing and responding circuits .When the EMT transcription factors was present, we observed a 5.8-fold signal increase in the system. Then, we successfully distinguished mesenchymal breast cancer cells from epithelial cancer cells and repressed the proliferation of EMT tumor cells using our circuits. The EMT sensing and responding circuits are promising tools for the identification of EMT cells, which is crucial for EMT-related disease therapy and investigating the mechanisms underlying the reversible EMT process.

Medicine Targeting Epithelial-Mesenchymal Transition to Treat Airway Remodeling and Pulmonary Fibrosis Progression

Objective. Dysregulation of epithelial-mesenchymal transition (EMT) in the airway epithelium is associated with airway remodeling and the progression of pulmonary fibrosis. Many treatments have been shown to inhibit airway remodeling and pulmonary fibrosis progression in asthma and chronic obstructive pulmonary disease (COPD) by regulating EMT and have few side effects. This review aimed to describe the development of airway remodeling through the EMT pathway, as well as the potential therapeutic targets in these pathways. Furthermore, this study aimed to review the current research on drugs to treat airway remodeling and their effects on the EMT pathway. Findings. The dysregulation of EMT was associated with airway remodeling in various respiratory diseases. The cytokines released during inflammation may induce EMT and subsequent airway remodeling. Various drugs, including herbal formulations, specific herbal compounds, cytokines, amino acid or protein inhibitors, microRNAs, and vitamins, may suppress airway remodeling by inhibiting EMT-related pathways.

Mesenchymal stem cell-derived exosomes enriched with miR-218 reduce the epithelial–mesenchymal transition and angiogenesis in triple-negative breast cancer cells

BackgroundThe epithelial–mesenchymal transition (EMT) and angiogenesis are morphogenetic processes implicated in tumor invasion and metastasis. It is found that the aberrant expression of microRNAs (miRNAs) contributes to these processes. Exosomes are considered potential natural vehicles for miRNA delivery in cancer therapy. miR-218 is one of the tumor suppressor miRNAs and its downregulation is associated with EMT and angiogenesis. We aimed to use adipose mesenchymal stem cells-derived exosomes (ADMSC-exosomes) for miR-218 delivery to breast cancer cells and evaluate miR-218 tumor-suppressing properties in vitro.MethodsExosomes were isolated from conditioned media of ADMSCs. miR-218 was loaded to exosomes using electroporation. mRNA expression of target genes (Runx2 and Rictor) in MDA-MB-231 breast cancer cells was evaluated by qPCR. To explore the effects of miR-218 containing exosomes on breast cancer cells, viability, apoptosis, and Boyden chamber assays were performed. The angiogenic capacity of MDA-MB-231 cells after treatment with miR-218 containing exosomes was assessed by in vitro tube formation assay.ResultsmiR-218 mimic was efficiently loaded to ADMSC-exosomes and delivered to MDA-MB-231 cells. Exposure to miR-218 containing exosomes significantly decreased miR-218 target genes (Runx2 and Rictor) in MDA-MB-231 cells. They increased the expression of epithelial marker (CDH1) and reduced mesenchymal marker (CDH2). miR-218 restoration using miR-218 containing exosomes reduced viability, motility, invasion, and angiogenic capacity of breast cancer cells.ConclusionsThese findings suggest that ADMSC-exosomes can efficiently restore miR-218 levels in breast cancer cells and miR-218 can prevent breast cancer progression with simultaneous targeting of angiogenesis and EMT.

Drug Repurposing of Clinically Approved Drugs to Target Epithelial-mesenchymal Transition Using Molecular Docking Approach

Introduction: Epithelial-mesenchymal transition (EMT) is a process of epithelial transformation into mesenchymal cells. It is also a process that contributes to the progression of fibrosis and cancer metastasis. Transforming growth factor-beta (TGF-β), as a potent inducer of EMT, has therefore became a potential therapeutic target. However, clinical developments of TGF-β inhibitors have been un-successful due to safety risks. Hence, drug repurposing of existing safe-to-use drugs could over-come this issue. Methods: In this study, the TGF-β receptor type 1 (ALK5) was selected as the target protein. Molecular docking was performed using known ALK5 inhibitors as positive controls. Clinical drugs with similar binding affinity and amino acid interaction were selected for in vitro experimental validation. Results: ALK5 inhibitor demonstrated binding affinities ranging from -11.2 to -9.5 kcal/mol. Analysis of amino acid interaction revealed that Val219, Ala230, Lys232, and Leu340 amino acid residues are crucial for binding. Subsequent screening of clinically approved drugs against ALK5 showed top five potential drugs (ergotamine, telmisartan, saquinavir, indinavir, and nelfinavir). The selected drugs were tested in TGF-β1-induced normal human bronchial epithelial cell line, BEAS-2B. Western blot analysis showed that the drugs did not exhibit inhibitory effects on the downregulation of epithelial proteins (E-cadherin) and upregulation of mesenchymal proteins (vimentin and α-smooth muscle actin). Conclusion: Based on these experimental outcome, it is postulated that the results from molecular docking were false positives. The tested drugs in this study could serve as negative controls in future screening against ALK5 protein.

In Vitro and In Silico Analysis of Epithelial-Mesenchymal Transition and Cancer Stemness as Prognostic Markers of Clear Cell Renal Cell Carcinoma.

The process of epithelial-mesenchymal transition (EMT) involves the phenotypic transformation of cells from epithelial to mesenchymal status. The cells exhibiting EMT contain features of cancer stem cells (CSC), and the dual processes are responsible for progressive cancers. Activation of hypoxia-inducible factors (HIF) is fundamental to the pathogenesis of clear cell renal cell carcinoma (ccRCC), and their role in promoting EMT and CSCs is crucial for ccRCC tumour cell survival, disease progression, and metastatic spread. In this study, we explored the status of HIF genes and their downstream targets, EMT and CSC markers, by immunohistochemistry on in-house accrued ccRCC biopsies and adjacent non-tumorous tissues from patients undergoing partial or radical nephrectomy. In combination, we comprehensively analysed the expression of HIF genes and its downstream EMT and CSC-associated targets relevant to ccRCC by using publicly available datasets, the cancer genome atlas (TCGA) and the clinical proteome tumour analysis consortium (CPTAC). The aim was to search for novel biological prognostic markers that can stratify high-risk patients likely to experience metastatic disease. Using the above two approaches, we report the development of novel gene signatures that may help to identify patients at a high risk of developing metastatic and progressive disease.

Epithelial-mesenchymal transition as a potential route for DAPT resistance in breast cancer cells

Abstract Objectives Notch is a conserved pathway involved in cell-fate determination and homeostasis. Its dysregulation plays a role in poor prognosis and drug resistance in breast cancer. Targeting Notch signaling via inhibition of the gamma-secretase complex is in the spotlight of modern cancer treatments. Gamma-secretase inhibitors (GSI) have shown successful clinical activity in treating cancers, yet the possible resistance mechanism remains unstudied. Modeling the resistance and understanding culprit molecular mechanisms can improve GSI therapies. Accordingly, the aim of this study is to generate and analyze GSI-resistant breast cancer cells. Methods Gradually increasing doses of DAPT, a well-known GSI, were applied to MCF-7 breast cancer cell lines to generate resistance. Cell viability, migration and gene expressions were assessed by MTT, wound healing and qRT-PCR analyses. Results DAPT-resistant MCF-7 cells exhibited abnormal expression of Notch receptors, Notch targets (HES1, HES5, HEY1), and epithelial-mesenchymal transition (EMT) markers (E-cadherin, ZO-1, SNAIL2, N-cadherin) to overcome the continuous increase in DAPT toxicity by increased migration through mesenchymal transition. Conclusions This study prospects into the role of EMT in the potential resistance mechanism against DAPT treatment for breast cancer cells. Complementary targeting of EMT should be investigated further for a possible effect to potentiate DAPT’s anti-cancer effects.

Emerging trends and research foci of epithelial-mesenchymal transition in gliomas: A scientometric analysis and review.

Epithelial-mesenchymal transition (EMT) is a key factor in the invasion and migration of glioma cells, and the study of EMT in gliomas has become a hot topic over the past decade. Scientometric analysis is gaining more attention since it can obtain hot topics and emerging trends in a research field. This article analyzed the research related to EMT in gliomas for the first time, including descriptions of research situations, evaluations of research foci, and predictions of emerging trends. We searched the topic-related original articles from January 2012 to December 2021 in the Web of Science Core Collection (WoSCC) by using a specific strategy, and a total of 1,217 publications were obtained. The WoS platform, VOS viewer, and CiteSpace were used to analyze the annual distribution of publications and citations, authors and density of keywords, and other analyses including countries, institutions, references, clustering, burst analysis, and the timeline view of keywords. Scientometric analysis identified that the study of EMT in gliomas has developed fast and received continuous attention in the last decade. Based on the results of data analysis, most publications on the topic came from China, and the United States had the highest betweenness centrality. The top 10 co-cited references revealed the landmark documents that had greatly promoted the development of this field. The major focus is on the cellular and molecular mechanisms of EMT in gliomas, and the therapy related to EMT target and non-coding RNAs has been developing fast in recent years. This study revealed the intimate connections between EMT and gliomas, and the complex mechanisms regulating EMT in gliomas had been studied widely in the last decade. Exploring the deep mechanisms of EMT in gliomas is the foundation of the targeted inhibitions, which can promote the development of therapies for gliomas.

Transforming growth factor-β-induced secretion of extracellular vesicles from oral cancer cells evokes endothelial barrier instability via endothelial-mesenchymal transition

BackgroundDuring metastasis, cancer cells undergo epithelial-mesenchymal transition (EMT) in response to transforming growth factor-β (TGF-β), which is abundant in the tumor microenvironment, and acquire invasive and metastatic potentials. Metastasis to distant organs requires intravascular invasion and extravasation of cancer cells, which is accompanied by the disruption of the adhesion between vascular endothelial cells. Cancer cell-derived extracellular vesicles (EVs) have been suggested to induce the destabilization of normal blood vessels at the metastatic sites. However, the roles of EVs secreted from cancer cells that have undergone EMT in the destabilization of blood vessels remain to be elucidated. In the present study, we characterized EVs secreted by oral cancer cells undergoing TGF-β-induced EMT and elucidated their effects on the characteristics of vascular endothelial cells.MethodsInduction of EMT by TGF-β in human oral cancer cells was assessed using quantitative RT-PCR (qRT-PCR) and immunocytochemistry. Oral cancer cell-derived EVs were isolated from the conditioned media of oral cancer cells that were treated with or without TGF-β using ultracentrifugation, and characterized using nanoparticle tracking analysis and immunoblotting. The effects of EVs on human umbilical artery endothelial cells were examined by qRT-PCR, cellular staining, and permeability assay. The significant differences between means were determined using a t-test or one-way analysis of variance with Tukey’s multiple comparisons test.ResultsOral cancer cells underwent EMT in response to TGF-β as revealed by changes in the expression of epithelial and mesenchymal cell markers at both the RNA and protein levels. Oral cancer cells treated with TGF-β showed increased EV production and altered EV composition when compared with untreated cells. The EVs that originated from cells that underwent EMT by TGF-β induced endothelial-mesenchymal transition, which was characterized by the decreased and increased expression of endothelial and mesenchymal cell markers, respectively. EVs derived from oral cancer cells also induced intercellular gap formation which led to the loss of endothelial cell barrier stability.ConclusionsEVs released from oral cancer cells that underwent TGF-β-induced EMT target endothelial cells to induce vascular destabilization. Detailed characterization of oral cancer-derived EVs and factors responsible for EV-mediated vascular instability will lead to the development of agents targeting metastasis.

Drugs targeting epithelial-mesenchymal transition molecules for treatment of lichen planopilaris.

Primary cicatricial alopecia (PCA), also known as scarring alopecia, comprises a diverse group of hair disorders that cause permanent destruction of the pilosebaceous unit, resulting in disappearance of the follicular ostia. Lichen planopilaris (LPP) is a subtype of primary lymphocytic cicatricial alopecia. There is an urgent need to identify novel molecules that successfully target specific pathogenic pathways in LPP to inhibit and reverse disease progression. Recent studies into LPP pathogenesis have discovered that follicular stem cells undergo epithelial-mesenchymal transition (EMT). We sought to identify drugs that target molecules involved in EMT to repurpose these drugs for treatment of LPP. We identified 8 molecules and 15 drugs that target these EMT molecules. Only four of these drugs (pioglitazone, tofacitinib, barcitinib and apremilast) have been reported in individual cases or case series of patients with LPP and controlled studies are missing. We describe each drug and mechanism of action target EMT in detail. Although previous studies have demonstrated the efficacy of EMT inhibitors in anticancer therapy, there are, to our knowledge, no studies using EMT-attenuating drugs for the treatment of LPP. The treatment molecules discussed in this paper provide a new platform for clinical studies and controlled trials in LPP.

Autophagy and EMT in cancer and metastasis: Who controls whom?

Metastasis consists of hallmark events, including Epithelial-Mesenchymal Transition (EMT), angiogenesis, initiation of inflammatory tumor microenvironment, and malfunctions in apoptosis. Autophagy is known to play a pivotal role in the metastatic process. Autophagy has pulled researchers towards it in recent times because of its dual role in the maintenance of cancer cells. Evidence states that cells undergoing EMT need autophagy in order to survive during migration and dissemination. Additionally, it orchestrates EMT markers in certain cancers. On the other side of the coin, autophagy plays an oncosuppressive role in impeding early metastasis. This review aims to project the interrelationship between autophagy and EMT. Targeting EMT via autophagy as a useful strategy is discussed in this review. Furthermore, for the first time, we have covered the possible reciprocating roles of EMT and autophagy and its consequences in cancer metastasis.

Abstract P4-07-19: Quantifying epithelial-mesenchymal tumor heterogeneity for prediction of patient prognosis based on EMT state

Abstract Background: Triple Negative Breast Cancer (TNBC) is an aggressive and heterogeneous subtype characterized by ER/PR/HER2 negative status. Much of the disease potential and aggressive nature of this subtype derives from inter- and intra-tumoral heterogeneity, which makes developing targeted therapies challenging. A key contributor to both heterogeneity in TNBC and later stage chemo-resistance and metastasis is the Epithelial-to-Mesenchymal transition (EMT). This developmental program is frequently exploited in the context of cancer to increase migratory abilities, invasiveness, metastatic potential, and resistance to chemotherapy. Indeed, EMT has been demonstrated and linked to poor prognosis and decreased survival in many solid cancer types. Cells have been found to reside in multiple stable intermediate states along the EMT spectrum, which confer increased aggressive, metastatic, and chemoresistance attributes to a heterogeneous tumor through increased stem-like characteristics. Identifying and targeting this disease-potentiating population in patient tumors is a major hurdle in overcoming metastatic disease. Knowledge gap: Despite major advances in our understanding, the contributions of EMT research to improvements in diagnostic pathology or cancer therapy have been minimal. One reason for this gap stems from our inability to accurately detect and quantify epithelial-mesenchymal heterogeneity in primary tumor specimens. Secondly, the significance of recently identified intermediate or partial EMT states to predicting tumor prognosis and therapy response are unclear. Approach &amp; Results: To study the role of various states within the EMT spectrum and their regulatory networks, the heterogeneous breast cancer cell line, SUM149PT, was used to derive six single cell clones encompassing the spectrum of EMT states, from epithelial to mesenchymal. Interrogation of this model system in vivo has revealed increased tumor growth and metastatic potential in the intermediate EMT states when compared to the extreme epithelial and mesenchymal states. To further elucidate EMT states in vivo, we employ a 6-marker multi-round immunofluorescence-based staining approach to identify cells that reside in various states along the EMT spectrum. We subsequently used an entropy-based approach and nearest-neighbor analysis on these tumors with the purpose of scoring heterogeneity and overall EMT state. Notably, this analysis segregated stromal infiltrates and their contributions to aggregate EMT scoring, which has been a major hurdle in using EMT as a scoring metric in patient samples. Overall, SUM149 clone-derived tumors held true to the relative EMT states of the starting cell populations; intermediate-derived tumors displayed high heterogeneity while epithelial and mesenchymal clone-derived tumors had lower levels of heterogeneity, despite retaining different EMT scores. Decoupling of heterogeneity and EMT state in this way provides two metrics to assess potential metastatic ability of a tumor. This staining method and analysis has been successfully applied in a preliminary set of patient tumors, showing promise for these two factors, E-M Heterogeneity and EMT score, as a tumor prognostic indicator to inform therapeutic decision-making. Conclusions: EMT tumor states and EMT-derived intra-tumoral heterogeneity play an important role in tumor metastasis and disease progression. Here, we have validated a multiplexed staining approach to quantify these metrics within a tumor, while segregating out stromal infiltrating cells. In the future, this staining and quantification shows promise as a means of predicting patient prognosis and informing potential treatment options based on targeting EMT states Citation Format: Meredith S Brown, Behnaz Abdollahi, Nevena Ognjenovic, Kristen E Muller, Saeed Hassanpour, Diwakar R Pattabiraman. Quantifying epithelial-mesenchymal tumor heterogeneity for prediction of patient prognosis based on EMT state [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P4-07-19.

Propolin G-Suppressed Epithelial-to-Mesenchymal Transition in Triple-Negative Breast Cancer Cells via Glycogen Synthase Kinase 3β-Mediated Snail and HDAC6-Regulated Vimentin Degradation.

Triple-negative breast cancer (TNBC) is a highly aggressive breast cancer with a poor prognosis. The incidence and mortality rate of TNBC are frequently found in younger women. Due to the absence of a good therapeutic strategy, effective remedies for inhibiting TNBC have been developed for improving the cure rate. Epithelial-to-mesenchymal transition (EMT) is a critical mechanism to regulate cancer cell motility and invasion. Furthermore, ectopic expression of EMT molecules correlates with the metastasis and poor prognosis of TNBC. Targeting EMT might be a strategy for the therapy and prevention of TNBC. Propolin G, an active c-prenylflavanone in Taiwanese propolis, has been shown to possess anti-cancer activity in many cancers. However, the anti-metastasis activity of propolin G on TNBC is still unclear. The present study showed that the migration and invasion activities of TNBC cells was suppressed by propolin G. Down-regulated expression of Snail and vimentin and up-regulated expression of E-cadherin were dose- and time-dependently observed in propolin G-treated MDA-MB-231 cells. Propolin G inhibited Snail and vimentin expressions via the signaling pathways associated with post-translational modification. The activation of glycogen synthase kinase 3β (GSK-3β) by propolin G resulted in increasing GSK-3β interaction with Snail. Consequently, the nuclear localization and stability of Snail was disrupted resulting in promoting the degradation. Propolin G-inhibited Snail expression and the activities of migration and invasion were reversed by GSK-3β inhibitor pretreatment. Meanwhile, the outcomes also revealed that histone deacetylase 6 (HDAC6) activity was dose-dependently suppressed by propolin G. Correspondently, the amounts of acetyl-α-tubulin, a down-stream substrate of HDAC6, were increased. Dissociation of HDAC6/Hsp90 with vimentin leading to increased vimentin acetylation and degradation was perceived in the cells with the addition of propolin G. Moreover, up-regulated expression of acetyl-α-tubulin by propolin G was attenuated by HDAC6 overexpression. On the contrary, down-regulated expression of vimentin, cell migration and invasion by propolin G were overturned by HDAC6 overexpression. Conclusively, restraint cell migration and invasion of TNBC by propolin G were activated by the expression of GSK-3β-suppressed Snail and the interruption of HDAC6-mediated vimentin protein stability. Aiming at EMT, propolin G might be a potential candidate for TNBC therapy.

Regulatory effects of lncRNAs and miRNAs on the crosstalk between autophagy and EMT in cancer: a new era for cancer treatment.

Autophagy and EMT (epithelial-mesenchymal transition) are the two principal biological processes and ideal therapeutic targets during cancer development. Autophagy, a highly conserved process for degrading dysfunctional cellular components, plays a dual role in tumors depending on the tumor stage and tissue types. The EMT process is the transition differentiation from an epithelial cell to a mesenchymal-like cell and acquiring metastatic potential. There is evidence that the crosstalk between autophagy and EMT is complex in cancer. In recent years, more studies have shown that long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) are involved in autophagy, EMT, and their crosstalk. Therefore, accurate understanding of the regulatory mechanisms of lncRNAs and miRNAs in autophagy, EMT and their interactions is crucial for the clinical management of cancers. An extensive literature search was conducted on the Google Scholar and PubMed databases. The keywords used for the search included: autophagy, EMT, crosstalk, lncRNAs, miRNAs, cancers, diagnostic biomarkers, and therapeutic targets. This search provided relevant articles published in peer-reviewed journals until 2021. Data from these various studies were extracted and used in this review. The results showed that lncRNAs/miRNAs as tumor inhibitors or tumor inducers could regulate autophagy, EMT, and their interaction by regulating several molecular signaling pathways. The lncRNAs/miRNAs involved in autophagy and EMT processes could have potential uses in cancer diagnosis, prognosis, and therapy. Such information could help find and develop lncRNAs/miRNAs based new tools for diagnosing, prognosis, and creating anti-cancer therapies.