Proliferation Of Endometrial Cancer Cells Research Articles

Obesity-induced extracellular vesicles proteins drive the endometrial cancer pathogenesis: therapeutic potential of HO-3867 and Metformin.

Endometrial cancer (EC) is the leading gynecologic malignancy in the United States with obesity implicated in 57% of cases. This research investigates the molecular complexities of extracellular vesicles (EV) secretion as carriers of oncogenic protein and their involvement in obesity-mediated EC. An understanding of these mechanisms is pivotal for unraveling pathways relevant to obesity-associated EC, thereby guiding the development of innovative prevention and treatment strategies. Our exploration revealed a significant increase in EV secretion carrying oncogenic proteins (TMEM205, STAT5, and FAS) in adipose and uterine tissues/serum samples from obese EC patients compared to control (without cancer). We identified alterations in EV-regulating proteins (Rab7, Rab11, and Rab27a) in obesity-mediated EC patients, adipose/uterine tissues, and serum samples. Through a 24-week analysis of the effects of a 45% kcal high-fat diet (HFD) on mice, we observed increased body weight, increased adipose tissue, enlarged uterine horns, and increased inflammation in the HFD group. This correlated with elevated levels of EV secretion and increased expression of oncogenic proteins TMEM205, FAS, and STAT5 and downregulation of the tumor suppressor gene PIAS3 in adipose and uterine tissues. Furthermore, our study confirmed that adipocyte derived EV increased EC cell proliferation, migration and xenograft tumor growth. Additionally, we identified that the small molecule inhibitors (HO-3867) or Metformin inhibited EV secretion in vitro and in vivo, demonstrating significant inhibition of high glucose or adipocyte-mediated EC cell proliferation and a reduction in body weight and adipose tissue accumulation when administered to HFD mice. Moreover, HO-3867 or Metformin treatment inhibited HFD induced hyperplasia (precursor of EC) by altering the expression of EV-regulated proteins and decreasing oncogenic protein expression levels. This study provides critical insights into the mechanisms underpinning obesity-mediated EV secretion with oncogenic protein expression, shedding light on their role in EC pathogenesis. Additionally, it offers pre-clinical evidence supporting the initiation of novel studies for EV-targeted therapies aimed at preventing obesity-mediated EC.

E2F1-induced upregulation of TROAP contributes to endometrial cancer progression.

To investigate the role of Trophinin-associated protein (TROAP) in endometrial cancer (EC) progression and elucidate how the transcription factor E2F transcription factor 1 (E2F1) modulates EC by upregulating TROAP expression. TROAP expression in EC tissues and cell lines was analyzed using bioinformatics databases, quantitative real-time polymerase chain reaction (qRT-PCR), western blot, and immunohistochemistry. TROAP was knocked down in EC cells to assess its effects on proliferation, migration, invasion, and glycolysis. Potential transcription factors regulating TROAP were identified, and the relationship between E2F1 and TROAP gene regulation was examined using dual luciferase assay. In vivo tumor growth was evaluated using a mouse xenograft model. TROAP was overexpressed in EC tissues and cell lines compared with normal controls. High TROAP expression correlated with poor differentiation, advanced stage, lymph node metastasis, and worse overall survival in EC patients. Knockdown of TROAP inhibited the proliferation, migration, invasion, and glycolytic capacity of EC cells. E2F1 was identified as a transcriptional activator of TROAP. E2F1 overexpression enhanced TROAP expression and promoted EC cell proliferation, migration, and glycolysis in a TROAP-dependent manner. TROAP knockdown suppressed tumor growth in vivo. TROAP is transcriptionally activated by E2F1 and promotes EC progression by enhancing cell proliferation, metastasis, and glycolysis. The E2F1-TROAP axis may serve as a potential therapeutic target for EC treatment.

Clinical Value Evaluation of SKA3 in Endometrial Cancer and Its Promotion of Proliferation and Migration of Endometrial Cancer Cells

Background: Endometrial cancer is one of the common cancers in gynecology, which seriously endangers women’s reproductive health. Therefore, it is urgent to search for new diagnostic and prognostic monitoring markers for endometrial cancer. This study aimed to explore the clinical significance and biological role of spindle and kinetochore-associated complex subunit 3 (SKA3) in endometrial cancer. Methods: Weighted gene co-expression network analysis (WGCNA) and identification of differentially expressed genes (DEGs) were conducted to identify the key gene in endometrial cancer. The clinical significance of SKA3 within endometrial cancer was assessed through receiver operating characteristic (ROC) and Kaplan-Meier (KM) curves. Spearman correlation analysis, the STRING database, Cytoscape software, and the molecular complex detection (MCODE) algorithm were employed to investigate genes associated with SKA3. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were carried out for elucidating the functional role and pathways involving SKA3. The cBioPortal online platform was utilized to explore mutations in SKA3. The biological effects of SKA3 were further investigated through Cell Counting Kit-8 (CCK8) and cell scratch experiments. Results: SKA3 emerges as a pivotal gene in endometrial cancer, exhibiting a statistically significant high expression level. Its area under the curve (AUC) for diagnosing endometrial cancer stands at 0.943. Patients displaying elevated SKA3 expression demonstrated a notably poorer prognosis. In the context of endometrial cancer, 9 genes directly interact with SKA3. The functional pathway of SKA3 in endometrial cancer likely involves the mitotic pathway. The alterations observed in SKA3 in endometrial cancer primarily manifest as “mutations”. Specifically, SKA3 exhibits 26 mutation sites in endometrial cancer, distributed across 7 distinct regions and involving 4 mutation types. Furthermore, SKA3 is implicated in promoting the proliferation and migration of HEC-1A cells. Conclusion: SKA3, a key gene in endometrial cancer, holds significant diagnostic and prognostic value and may influence the progression in endometrial cancer.

The mechanism of L1 cell adhesion molecule interacting with protein tyrosine kinase 2 to regulate the focal adhesion kinase–growth factor receptor-bound protein 2–son of sevenless–rat sarcoma pathway in the identification and treatment of type I high-risk endometrial cancer

Objective: The objective of this study was to investigate how L1 cell adhesion molecule (L1CAM) interacting with protein tyrosine kinase 2 (PTK2) affects endometrial cancer (EC) progression and determine its association with the focal adhesion kinase (FAK)–growth factor receptor-bound protein 2 (GRB2)–son of sevenless (SOS)–rat sarcoma (RAS) pathway. EC is a female cancer of major concern in the world, and its incidence has increased rapidly in recent years. L1CAM is considered a reliable marker of poor prognosis in patients with EC. Material and Methods: A single-center and prospective study was conducted using data from the Cancer Genome Atlas and samples from normal and EC tissues to explore the differential expression of L1CAM. Additional experimental models included human immortalized endometrial epithelium cells (hEECs) and EC cell lines such as KLE, RL95-2, and Ishikawa. L1CAM expression was regulated using lentiviruses designed for either overexpression or interference, and PTK2/focal adhesion kinase (FAK) signaling was inhibited with PF431396. Transfected KLE cells were injected into mice, and tumor growth was monitored over 14 days. Cellular proliferation and survival were assessed using cell counting kit, colony formation, and terminal deoxynucleotidyl transferase-mediated 2’-deoxyuridine 5’-triphosphate (dUTP) nick-end labeling assays. Metastatic behavior was evaluated through Transwell assays for cell migration and invasion. The expression levels of matrix metallopeptidase (MMP) 2 and MMP9 were determined by Western blot. In addition, the activation of the FAK–GRB2–SOS–RAS pathway was examined by assessing the protein levels of FAK, GRB2, SOS, and RAS. Results: There was a significant difference in L1CAM expression between EC tumor tissues and normal tissues, and L1CAM messenger RNA (1.85-fold) and L1CAM protein (2.59-fold) were significantly more expressed in EC tissues (P < 0.01) than in normal tissues. The tumor growth of L1CAM overexpressing EC cells was faster than that of negative control EC cells (6.43 fold; P < 0.001). L1CAM promoted the expression of FAK (1.43-2.72-fold; P < 0.001); enhanced EC cell proliferation (P < 0.01), survival and motility (P < 0.001), migration (P < 0.001), and invasion (P < 0.001); and activated the FAK–GRB2–SOS–RAS pathway, all of which were reversed when FAK expression was not upregulated (P < 0.001). Conclusion: By upregulating PTK2 and its encoded protein FAK, L1CAM was found to promote tumor progression and increase the activation of the FAK–GRB2–SOS–RAS pathway. These findings establish L1CAM and PTK2 as reference genes for poor prognostic prediction in EC and as targets for EC therapy, providing a valuable basis for distinguishing between benign and malignant endometrial conditions and justifying the necessity of targeted therapeutic approaches.

NCLN as a potential prognosis biomarker in endometrial cancer

Endometrial cancer (ECs) stands as one of the three major malignancies impacting females globally, with its incidence steadily increasing. ECs can be categorized into two types based on their clinicopathological features. Type I ECs typically exhibit low stage, favorable histological types, and low histological grade, correlating with a more favorable prognosis. Conversely, Type II ECs present with advanced-stage disease, aggressive behavior, and poorer histological types, resulting in a worse prognosis.The expression level of progesterone receptors (PR) holds significant importance in determining the prognosis of patients with ECs. Elevated levels of PR are linked to a more favorable prognosis, primarily attributed to progesterone's inhibitory influence on cancer cell proliferation and invasion. Moreover, progesterone promotes cell cycle inhibition through its regulation of PR, further contributing to improved outcomes in ECs.Nicalin (NCLN) plays a crucial role in facilitating the translocation of multichannel membrane proteins to the endoplasmic reticulum membrane and is implicated in embryonic development. Structurally akin to NODAL Modulator (NOMO), NCLN antagonizes NOMO during embryogenesis, forming a complex that antagonizes the Nodal pathway, thereby influencing mesoderm development. However, the precise relationship between NCLN and ECs remains incompletely understood.Our research findings reveal that NCLN actively stimulates the proliferation of ECs cells and exhibits a positive correlation with PR, albeit without impacting ER. Moreover, the expression levels of NCLN in ECs demonstrate associations with distinct histological types. These observations suggest that NCLN could emerge as a promising marker in the histological classification of ECs.

SOX4 inhibits ferroptosis and promotes proliferation of endometrial cancer cells via the p53/SLC7A11 signaling.

Sex-determining region Y-related high-mobility group box 4 (SOX4) has been reported to play a carcinogenic role in endometrial cancer (EC). However, the biological function and regulatory mechanisms of SOX4 in ferroptosis during the progression of EC are still unknown. The mRNA and protein levels were scrutinized by quantitative reverse-transcription polymerase chain reaction and western blot, respectively. The cell viability and proliferative capability were determined by cell counting kit-8 assay and 5-ethynyl-2'-deoxyuridine (EdU) assay. Transcriptional regulation of gene expression was investigated by dual-luciferase reporter assay and chromatin immunoprecipitation. Ferroptosis was evaluated by detection of reactive oxygen species, malondialdehyde, Fe2+, and ferroptosis-related proteins. The mice test was implemented to confirm the influence of SOX4 on EC tumor growth and ferroptosis in vivo. We here discovered the elevation of SOX4 in EC tissues and cells. Functionally, SOX4 knockdown hampered proliferation and promoted ferroptosis of EC cells. Mechanistically, SOX4 bound to p53 promoter and inhibited its transcriptional activity in EC cells. In addition, p53 transcriptionally suppressed SLC7A11 expression in EC cells. Downregulation of p53 reverses the effect of SOX4 knockdown on proliferation and ferroptosis of EC cells. Finally, in vivo experiments demonstrated that SOX4 depletion hindered tumor growth and triggered ferroptosis in EC. These findings collectively suggested that SOX4 inhibited ferroptosis and promoted proliferation of EC cells via the p53/SLC7A11 signaling. Our research unveiled a novel regulatory mechanism of ferroptosis in EC, offering promising perspectives for the development of EC therapies.

The oncogenic role of EIF4A3/CDC20 axis in the endometrial cancer.

Eukaryotic initiation factor 4A-3 (EIF4A3) is a key component of the exon junction complex (EJC) and is extensively involved in RNA splicing, inducing mRNA decay, and regulating the cell cycle and apoptosis. However, the potential role of EIF4A3 in EC has not been comprehensively investigated and remains unknown. Here, we report that the expression level of EIF4A3 is dramatically elevated in endometrial cancer (EC) samples compared with normal EC samples via bioinformatics analysis and immunohistochemistry analysis, and that high expression of EIF4A3 promotes the proliferation, migration, and invasion of EC cells. Mechanistically, we found that high EIF4A3 expression stabilized cell division cyclin 20 (CDC20) mRNA, and high EIF4A3 expression induced pro-carcinogenic effects in EC cells that were efficiently antagonized upon knockdown of CDC20, as well as Apcin, an inhibitor of CDC20. These findings reveal a novel mechanism by which high expression of EIF4A3 induces CDC20 upregulation, thus leading to EC tumorigenesis and metastasis, indicating a potential treatment strategy for EC patients with high EIF4A3 expression using Apcin. KEY MESSAGES: The expression level of EIF4A3 was dramatically elevated in endometrial cancer (EC) samples compared with normal endometrial cancer samples. High EIF4A3 expression stabilized CDC20 mRNA, and high EIF4A3 expression induced pro-carcinogenic effect in EC cells which was efficiently antagonized upon knockdown of CDC20. Apcin, an inhibitor of CDC20, could effectively counteract high expression of EIF4A3 inducing EC tumourigenesis and metastasis, indicating the potential treatment strategy for EC patients with EIF4A3 high expression by using Apcin.

MYO3B promotes cancer progression in endometrial cancer by mediating the calcium ion-RhoA/ROCK1 signaling pathway

PurposeThis study aimed to investigate the effect of MYO3B on endometrial cancer (EC) proliferation and invasion.MethodsThe expression of MYO3B in EC tissues and cells was analyzed using TCGA database, immunohistochemical staining, real-time PCR, and western blot (WB). Cell proliferation was detected by CCK8, Annexin V-APC/PI flow cytometry was used to detect apoptosis, intracellular calcium ion (Ca2+) was detected by flow cytometry with Fluo-4 AM fluorescent probe, cell migration by scratch assay, and cell invasion by Transwell assay, and the expression of proteins related to Ca2+ homeostasis and RhoA/ROCK1 signaling pathway was detected by WB and immunofluorescence staining.ResultsThe expression of MYO3B was an influential factor in EC recurrence, and the expression of MYO3B was significantly up-regulated in EC tissues and cells, but down-regulated in KLE cells, and MYO3B knockdown inhibited the proliferation, migration, and invasion ability of EC cells and promoted apoptosis, suggesting that MYO3B plays a tumor-promoting role in EC. Furthermore, MYO3B knockdown decreased Ca2+ concentration in EC cells and the RhoA/ROCK1 signaling pathway was inhibited, and the effect of MYO3B knockdown on RhoA/ROCK1 signaling was reversed by treatment with the Calmodulin agonist CALP-2, and the effects of MYO3B knockdown on cell proliferation, migration, and invasion were reversed after treatment with the RhoA agonist U-46,619.ConclusionMYO3B promotes the proliferation and migration of endometrial cancer cells via Ca2+-RhoA/ROCK1 signaling pathway. High expression of MYO3B may be a biomarker for EC metastasis.

Ovatodiolide inhibits endometrial cancer stemness via reactive oxygen species-mediated DNA damage and cell cycle arrest

Endometrial cancer (EC) is a common gynecological cancer worldwide, often associated with a poor prognosis after recurrence or metastasis. Ovatodiolide (OVA) is a macrocyclic diterpenoid derived from Anisomeles indica that shows anticancer effects in various malignancies. This study aimed to evaluate the cytotoxic effects of OVA on EC cell proliferation and cancer stem cell (CSC) activity and explore its underlying molecular mechanisms. OVA treatment dose-dependently reduced the viability and colony formation of three EC cell lines (AN3CA, HEC-1A, and EMC6). It induced G2/M phase cell cycle arrest, associated with decreased cell division cycle 25C (CDC25C) expression and reduced activation of cyclin-dependent kinases 1 (CDK1) and 2 (CDK2). OVA also increased reactive oxygen species (ROS) production and DNA damage, activating the DNA damage-sensitive cell cycle checkpoint kinases 1 (CHK1) and 2 (CHK2) and upregulating the DNA damage marker γ-H2A.X variant histone (H2AX). It also suppressed the activation of mechanistic target of rapamycin kinase (mTOR) and nuclear factor kappa B (NF-κB) and downregulated glutathione peroxidase 1 (GPX1), an antioxidant enzyme counteracting oxidative stress. Moreover, OVA reduced the self-renewal capacity of CSCs, reducing the expression of key stemness proteins Nanog homeobox (NANOG) and octamer-binding transcription factor 4 (OCT4). The ROS inhibitor N-acetylcysteine attenuated the anti-proliferative and anti-CSC effects of OVA. Our findings suggest that OVA acts via ROS generation, leading to oxidative stress and DNA damage, culminating in cell cycle arrest and the suppression of CSC activity in EC. Therefore, OVA is a promising therapeutic agent for EC, either as a standalone treatment or an adjunct to existing therapies.

Role of INPP4B in the proliferation, migration, invasion, and survival of human endometrial cancer cells.

Inositol polyphosphate 4-phosphatase type II (INPP4B) has been identified as a tumor repressor in several human cancers while its role in endometrial cancer has not been investigated yet. Therefore, the current study was designed to determine whether INPP4B participates in the progression of endometrial cancer by utilizing clinical data and experimental determination. We first include six chemotherapy-treated patients with recurrent and metastatic endometrioid carcinoma to determine the relationship between INPP4B mutation and relative tumor burden. By using siRNA-mediated gene silencing and vector-mediated gene overexpression, we further determined the effect of manipulating INPP4B expression on the proliferation, invasion, and survival of endometrial cancer cells. Furthermore, the repressing effect of INPP4B together with its role in chemotherapy was further validated by xenograft tumor-bearing mice models. Western blot analysis was used to explore further downstream signaling modulated by INPP4B expression manipulation. Two of the patients were found to have INPP4B mutations and the mutation frequency of INPP4B increased during the progression of chemotherapy resistance. Endometrial cancer cells with silenced INPP4B expression were found to have promoted tumor cell proliferation, invasion, and survival. Endometrial cancer cells overexpressing INPP4B were found to have decreased tumor cell proliferation, invasion, and survival. An in vivo study using six xenograft tumor-bearing mice in each group revealed that INPP4B overexpression could suppress tumor progression and enhance chemosensitivity. Furthermore, INPP4B overexpression was found to modulate the activation of Wnt3a signaling. The current study suggested that INPP4B could be a suppressor in endometrial cancer progression and might be a target for endometrial cancer treatment. Also, INPP4B might serve as a predictor of chemosensitivity determination.

ERP29 regulates the proliferation of endometrial carcinoma via M6A modification

AimsEndoplasmic reticulum protein 29 (ERP29) is crucial for endoplasmic reticulum stress (ERS). M6A plays an important role in the progression of endometrial cancer (EC). The study investigated the role of ERS-related gene (ERP29) and m6A in EC. Materials and methodsWe screened ERS-related genes based on the GEO dataset, GSEA dataset and TCGA-UCEC database using WGCNA and two machine learning algorithms. The m6A-related GEO dataset was employed to identify the ERS-related hub genes with m6A. Expression of hub genes in different cell types were visualize through scRNA-seq data analyzing. Using qPCR, Western blot, and Immunohistochemical assays to detect the expression of ERP29, the effect of ERP29 on cancer cell proliferation was investigated through CCK8, EdU and clone formation experiments. M6A modifications were studied using m6A Dot blot and MeRIP-qPCR. Finally, we conducted rescue experiments. Key findingsTen ERS-related hub genes with m6A were identified. ERP29 is highly expressed in EC. ERP29 knockdown inhibits EC cell proliferation. METTL3 overexpression increases the ERP29 mRNA m6A and decreases the expression of ERP29. Cycloleucine (Cyc), a nucleic acid methylation inhibitor, treatment reduces ERP29 mRNA m6A and increases the expression of ERP29. Cyc rescue the low expression of ERP29 caused by overexpression of METTL3 through m6A. ERP29 knockdown rescued the increased proliferation of EC cells caused by low m6A. SignificanceERP29 is highly expressed in EC. m6A regulates ERP29 expression and affects the proliferation of endometrial cancer cells. This represents the premise for applying ERP29 and m6A modifications in diagnosing and treating EC.

CHD4 R975H mutant activates tumorigenic pathways and promotes stemness and M2-like macrophage polarization in endometrial cancer

Endometrial cancer (EC), one of the most prevalent carcinomas in females, is associated with increasing mortality. We identified the CHD4 R975H mutation as a high-frequency occurrence in EC patients through a comprehensive survey of EC databases. Computational predictions suggest that this mutation profoundly impacts the structural and functional integrity of CHD4. Functional assays revealed that the CHD4 R975H mutation enhances EC cell invasion, proliferation, and colony formation, promoting a cancer stem cell (CSC)-like phenotype. RNA-seq analysis of cells expressing CHD4 R975H mutant revealed a transcriptomic landscape marked by the activation of several cancer-promoting signaling pathways, including TNF-α signaling via NF-κB, KRAS, P53, mTOR, TGF-β, EGFR, Myc and growth factor signaling. Validation assays confirmed the activation of these pathways, further demonstrating that CHD4 R975H mutation induces stemness in EC cells and M2-like polarization of tumor-associated macrophages (TAMs). Our study elucidated the oncogenic role of CHD4 R975H mutation, highlighting its dual impact on facilitating cancer stemness and transforming TAMs into an immunosuppressive subtype. These findings contribute valuable insights into the molecular mechanisms driving EC progression and open avenues for targeted therapeutic interventions.

NAP1L1 Promotes Endometrial Cancer Progression via EP300-Mediated DDX5 Promoter Acetylation.

Endometrial cancer (EC) is one of the predominant tumors of the female reproductive system. In this current study, we investigated the functions and related mechanisms of NAP1L1/DDX5 in EC. This retrospective study analyzed the medical records of EC patients, collected tissue samples for NAP1L1 and DDX5 staining, and conducted survival analysis using the Kaplan-Meier method. To evaluate the impact of NAP1L1 and/or DDX5 on cellular processes in EC cells, several techniques were employed. These included CCK-8 assay, wound healing assay, Transwell assay, as well as overexpression or knockdown of target gene expression. Additionally, ChIP, dual luciferase reporter gene, Co-IP assay were utilized to confirm the interaction between NAP1L1, EP300 and DDX5. Furthermore, qRT-PCR, western blot and Co-IP assay were performed to analyze the modulation of NAP1L1/DDX5 in Wnt/β-catenin. NAP1L1 and DDX5 expression were upregulated in EC tissues, and correlated with poor prognosis. NAP1L1/DDX5 promoted EC cell proliferation, migration and invasion. NAP1L1 promotes acetylation and transcription by recruiting EP300 to the DDX5 promoter. DDX5 could activate Wnt/β-catenin signal by binding to β-catenin. In animal models, knockdown of NAP1L1 inhibits EC tumor growth and lung metastasis. To sum up, our study demonstrated that NAP1L1 promoted the malignant phenotypes of EC cells via recruiting EP300 to promote DDX5 acetylation, thus activating the Wnt/β-catenin signaling pathway. Implications: Our research findings indicate that targeting the NAP1L1/EP300/DX5 axis might be a new potential treatment option for endometrial cancer.

Downregulation of ATP5F1D inhibits mtROS/NLRP3/caspase-1/GSDMD axis to suppress pyroptosis-mediated malignant progression of endometrial cancer

PurposeIn developed countries, endometrial cancer (EC) is the most prevalent gynecological cancer and its occurrence is associated with chronic inflammation. ATP5F1D is a subunit of ATP synthase (complex V), as well as the important component of mitochondrial electron transport chain (ETC). ETC play compelling roles in carcinogenesis. To date, little is known about the role of ATP5F1D in EC. MethodsATP5F1D expression was identified in EC tissues and EC cell lines. We evaluated the influence of ATP5F1D on clinical features and prognosis based on TCGA database. The effects of ATP5F1D in EC malignant progression by applying loss-of-function assays in KLE and Ishikawa cell lines were detected by EdU, CCK-8, wound healing, Transwell, and flow cytometry assays. Additionally, electron microscope, LDH release, ELISA, mitochondrial ROS measurement, and Immunofluorescence were performed to demonstrate ATP5F1D can affect the pyroptosis of EC. To observe the anti-tumor effect on ATP5F1D silencing, we established an in vivo human endometrial tumor model using nude mice. ResultsATP5F1D expression was significantly upregulated in EC and was associated with favorable prognosis. ATP5F1D knockdown inhibited the proliferation, invasion, and migration of EC cells. Similarly, in nude mice, ATP5F1D knockdown suppressed the growth EC cells. Knocking down ATP5F1D lead to decrease the production of mitochondrial ROS (mtROS) and inhibited pyroptosis of EC cells. ConclusionDownregulation of ATP5F1D as a new therapeutic strategy that could mediate pyroptosis via suppressing mtROS/NLRP3/caspase-1/GSDMD pathway to inhibit EC progression.

ACAT2 negatively modulated by FOXA2 suppresses ferroptosis to expedite the aggressive phenotypes of endometrial cancer cells.

Endometrial cancer (EC) remains a prevalent gynecological disease with a continuously rising incidence and fatality rate. Acyl coenzyme A: cholesterol acyltransferase 2 (ACAT2) has been commonly perceived as a tumor promoter in multiple human malignancies. This study was conducted to specify the role and mechanism of ACAT2 in EC, which has not been covered. The expression and prognostic significance of ACAT2 in EC samples were respectively analyzed by the ENCORI and Kaplan-Meier plotter databases. RT-qPCR and western blot examined ACAT2 and forkhead box protein A2 (FOXA2) expression in EC cells. The CCK-8 method, colony formation, and EdU staining assays detected cell proliferation. The cell cycle was detected by flow cytometry analysis. Wound healing and Transwell assays, respectively, estimated cell migration and invasion. The thiobarbituric acid reactive species (TBARS) method and BODIPY 581/591 C11 probe detected lipid peroxidation levels. FerroOrange staining estimated intracellular iron level. Western blot examined the expression of epithelial-mesenchymal transition (EMT) and ferroptosis-associated proteins. The human TFDB database predicted the binding of FOXA2 with the ACAT2 promoter, which was substantiated by ChIP and luciferase reporter assays. As a result, ACAT2 expression was increased in EC tissues and cells and associated with poor survival outcomes in EC patients. ACAT2 deletion might hinder EC cell proliferation, migration, invasion, and EMT while stimulating cell cycle arrest. Moreover, ACAT2 silencing promoted the ferroptosis of EC cells. Also, FOXA2 inactivated the transcription of ACAT2 through binding with the ACAT2 promoter. FOXA2 interference could promote the proliferation, migration, invasion, EMT, cell cycle, and ferroptosis of ACAT2-silenced EC cells, which was partially reversed by the ferroptosis activator erastin. Conclusively, ACAT2 transcriptionally inactivated by FOXA2 might contribute to the malignant progression of EC via the inhibition of ferroptosis.

Clinical significance of TROAP in endometrial cancer and the antiproliferative and proapoptotic effects of TROAP knockdown in endometrial cancer cells: integrated utilization of bioinformatic analysis and in vitro test verification.

Trophinin-associated protein (TROAP), a cytoplasmic protein essential for spindle assembly and centrosome integrity during mitosis, has been reported to serve as an oncogene in various tumors. However, its role in endometrial cancer (EC) progression is still undefined. TROAP expression in EC was analyzed via GEPIA and HPA databases. The diagnostic and prognostic values of TROAP were examined by ROC curve analysis and Kaplan-Meier plotter, respectively. Cell proliferation was evaluated using CCK-8 and EdU incorporation assays. Apoptosis was assessed using TUNEL and flow cytometry assays. GSEA was performed to explore TROAP-related pathways in EC. Expression of TROAP, proliferating cell nuclear antigen (PCNA), Ki-67, cleaved-caspase-3 (cl-caspase-3), caspase-3, active β-catenin, and total β-catenin was detected using western blot analysis. TROAP was upregulated in EC. TROAP served as a potential diagnostic and prognostic marker in EC patients. TROAP silencing suppressed proliferation and enhanced apoptosis in EC cells. GSEA revealed that EC and Wnt signaling pathways were related to the expression of TROAP. We further demonstrated that TROAP knockout repressed the Wnt/β-catenin pathway in EC cells. Moreover, SKL2001, a Wnt/β-catenin activator, partially abrogated the effects of TROAP silencing on EC cell proliferation and apoptosis, while the signaling inhibitor XAV-939 had the opposite effect. In conclusion, TROAP knockout retarded proliferation and elicited apoptosis in EC cells by blocking the Wnt/β-catenin pathway.

SNORD99 promotes endometrial cancer development by inhibiting GSDMD-mediated pyroptosis through 2'-O-methylation modification.

Eukaryotic cells possess multiple mechanisms of self-destruction, including pyroptosis and necroptosis. Pyroptosis is a type of programmed cell death characterized by cellular rupture and linked to inflammation. SnoRNA, a small non-coding RNA in the nucleolus, can dysregulate specific RNAs through 2'-O-methylation, contributing to tumorigenesis. Our StarBase and qRT-PCR analysis revealed SNORD99 upregulation in endometrial cancer (EC) tissue compared to normal tissue, suggesting its role in pathogenesis. SNORD99 overexpression enhanced migration and proliferation of EC cells, while ASO-mediated suppression reduced malignant cell spread and division. RNA-seq and base-comparing analysis identified GSDMD's differential expression upon SNORD99 overexpression, forming the SNORD99-FBL RNP complex. RTL-P experiments showed SNORD99 increased GSDMD's 2'-O-methylation. SNORD99 reduced GSDMD, caspase-1, and NLRP3 protein levels, implicating its role in pyroptosis. Optical and electron microscopy confirmed enhanced pyroptosis features. In summary, SNORD99 modifies GSDMD via 2'-O-methylation, suppressing pyroptosis and promoting EC progression. Developing pyroptosis-inducing drugs may offer new cancer treatment avenues.

IGF2BP2-modified circular RNA circCHD7 promotes endometrial cancer progression via stabilizing PDGFRB and activating JAK/STAT signaling pathway

Circular RNAs (circRNAs) represent a class of covalently closed, single-stranded RNAs and have been linked to cancer progression. N6-methyladenosine (m6A) methylation is a ubiquitous RNA modification in cancer cells. Increasing evidence suggests that m6A can mediate the effects of circRNAs in cancer biology. In contrast, the post-transcriptional systems of m6A and circRNA in the progression of endometrial cancer (EC) remain obscure. The current study identified a novel circRNA with m6A modification, hsa_circ_0084582 (circCHD7), which was upregulated in EC tissues. Functionally, circCHD7 was found to promote the proliferation of EC cells. Mechanistically, circCHD7 interacted with insulin-like growth factor 2 mRNA-binding protein (IGF2BP2) to amplify its enrichment. Moreover, circCHD7 increased the mRNA stability of platelet-derived growth factor receptor beta (PDGFRB) in an m6A-dependent manner, thereby enhancing its expression. In addition, the circCHD7/IGF2BP2/PDGFRB axis activated the JAK/STAT signaling pathway and promoted EC cell proliferation. In conclusion, these findings provide new insights into the regulation of circRNA-mediated m6A modification, and the new “circCHD7-PDGFRB” model of regulation offers new perspectives on circCHD7 as a potential target for EC therapy.

Palmitic Acid Exerts Anti-Tumorigenic Activities by Modulating Cellular Stress and Lipid Droplet Formation in Endometrial Cancer.

Epidemiological and clinical evidence have extensively documented the role of obesity in the development of endometrial cancer. However, the effect of fatty acids on cell growth in endometrial cancer has not been widely studied. Here, we reported that palmitic acid significantly inhibited cell proliferation of endometrial cancer cells and primary cultures of endometrial cancer and reduced tumor growth in a transgenic mouse model of endometrial cancer, in parallel with increased cellular stress and apoptosis and decreased cellular adhesion and invasion. Inhibition of cellular stress by N-acetyl-L-cysteine effectively reversed the effects of palmitic acid on cell proliferation, apoptosis, and invasive capacity in endometrial cancer cells. Palmitic acid increased the intracellular formation of lipid droplets in a time- and dose-dependent manner. Depletion of lipid droplets by blocking DGAT1 and DGAT2 effectively increased the ability of palmitic acid to inhibit cell proliferation and induce cleaved caspase 3 activity. Collectively, this study provides new insight into the effect of palmitic acid on cell proliferation and invasion and the formation of lipid droplets that may have potential clinical relevance in the treatment of obesity-driven endometrial cancer.

LIN28B induced PCAT5 promotes endometrial cancer progression and glycolysis via IGF2BP3 deubiquitination

Endometrial cancer (EC) cells exhibit abnormal glucose metabolism, characterized by increased aerobic glycolysis and decreased oxidative phosphorylation. Targeting cellular glucose metabolism in these cells could be an effective therapeutic approach for EC. This study aimed to assess the roles of LIN28B, PCAT5, and IGF2BP3 in the glucose metabolism, proliferation, migration, and invasion of EC cells. LIN28B highly expressed in EC, binds and stabilizes PCAT5. PCAT5, overexpressed in EC, and its 1485-2288nt region can bind to the KH1-2 domain of IGF2BP3 to prevent MKRN2 from binding to the K294 ubiquitination site of IGF2BP3, thus stabilizing IGF2BP3. Finally, IGF2BP3 promotes the aerobic glycolysis, proliferation, migration and invasion of EC cells by stabilizing the key enzymes of glucose metabolism HK2 and PKM2. Taken together, our data reveal that the LIN28B/PCAT5/IGF2BP3 axis is critical for glucose reprogramming and malignant biological behavior in EC cells. Therefore, targeting this axis may contribute to the development of a novel therapeutic strategy for EC metabolism.