E2F1 Levels Research Articles

Profiling mRNA and miRNA expression variations associated with cyclin-dependent kinase pathway in the low-grade luminal early breast cancer.

Luminal A and B subtypes of breast tumors have fluctuated in proliferation rates, which arise from cell cycle dysregulation in cancer. Besides, microRNAs can regulate various cell processes through integration with mRNA. miRNAs that target the cell cycle are significant because of their prediction capability of prognosis. The objective of this study is to discover the integration between miRNA-mRNA and miRNA-miRNA related to cyclin-dependent kinase. Thirty-four pairs of human primary breast cancer and tumor margin samples from luminal breast cancer patients were investigated to assess the expression levels of CCND1, E2F1, miR-124, miR-503, miR-449a, and miR-449b. Afterward, the expression levels of mRNAs and miRNAs were investigated by real-time PCR. Statistical analysis was conducted to compare the expression levels between breast cancer and corresponding normal tissues. The protein expressions of E2F1 and CCND1 were verified by western blotting. Further, the correlation between mRNAs and miRNAs was calculated. E2F1 was significantly increased in both luminal A and B patients, while CCND1 was upregulated only in luminal B. Significant differences in all miRNAs were detected in both luminal A and B biopsy specimens (p < 0.0001). The correlation analysis revealed a positive strong correlation between miR-124 and E2F1 in luminal A patient. Moreover, the correlation test confirmed the ability of miR-449a to increase the CCND1 gene in luminal B subtypes. Also, miRNA correlation exhibited the miRNA-miRNA interaction in luminal breast cancer. This study demonstrated the novel miRNA-mRNA and miRNA-miRNA interactions, providing new insights into the molecular integration in luminal A and B patients. The authors propose that this research could contribute to introducing valuable biomarkers for luminal cancerous cells.

LncRNA HAGLR regulates gastric cancer progression by regulating the miR-20a-5p/E2F1 axis.

Gastric cancer (GC) stands as a prevalent and challenging malignancy within the gastrointestinal tract. The potential of long non-coding RNAs (lncRNAs) as biomarkers and therapeutic targets in oncology has garnered immense research interest. This study aims to elucidate the relevance, biological roles, and mechanistic pathways of LncRNA HAGLR in the context of GC. The assessments of cell proliferation, migration, and invasion were executed using CCK-8, wound healing, and Transwell assays. The interactions between HAGLR, miR-20a-5p, and E2F1 were appraised through luciferase reporter assays, fluorescence in situ hybridization (FISH), and RNA immunoprecipitation (RIP). A tumor xenograft model provided in vivo validation for in vitro findings. Elevated levels of HAGLR in GC cells and tissue specimens were linked to worse patient outcomes. The inhibition of HAGLR led to a decrease in GC cell proliferation, migration, and invasion, whereas its activation prompted contrary effects. The impact of HAGLR on cell migration and invasion was notably associated with epithelial-mesenchymal transition (EMT). Through bioinformatics, luciferase reporter assays, FISH, RIP, and Western blot analyses, it was revealed that HAGLR acts as a molecular sponge for miR-20a-5p, consequently augmenting E2F1 levels. The data suggest that the HAGLR/miR-20a-5p/E2F1 regulatory cascade is implicated in GC pathogenesis, offering a novel therapeutic avenue for GC management.

In Vitro and In Vivo Evaluation of the Effects of Drug 2c and Derivatives on Ovarian Cancer Cells

Background: The identification of novel therapeutic strategies for ovarian cancer (OC), the most lethal gynecological neoplasm, is of utmost urgency. Here, we have tested the effectiveness of the compound 2c (4-hydroxy-2,6-bis(4-nitrobenzylidene)cyclohexanone 2). 2c interferes with the cysteine-dependent deubiquitinating enzyme (DUB) UCHL5, thus affecting the ubiquitin-proteasome-dependent degradation of proteins. Methods: 2c phenotypic/molecular effects were studied in two OC 2D/3D culture models and in a mouse xenograft model. Furthermore, we propose an in silico model of 2c interaction with DUB-UCHL5. Finally, we have tested the effect of 2c conjugated to several linkers to generate 2c/derivatives usable for improved drug delivery. Results: 2c effectively impairs the OC cell line and primary tumor cell viability in both 2D and 3D conditions. The effectiveness is confirmed in a xenograft mouse model of OC. We show that 2c impairs proteasome activity and triggers apoptosis, most likely by interacting with DUB-UCHL5. We also propose a mechanism for the interaction with DUB-UCHL5 via an in silico evaluation of the enzyme-inhibitor complex. 2c also reduces cell growth by down-regulating the level of the transcription factor E2F1. Eventually, 2c activity is often retained after the conjugation with linkers. Conclusion: Our data strongly support the potential therapeutic value of 2c/derivatives in OC.

NEK2 promotes the migration, invasion, proliferation of ESCC and mediates ESCC immunotherapy

PurposeEsophageal squamous cell carcinoma (ESCC) is a disease with a high incidence rate and high mortality worldwide. The Never in Mitosis A (NIMA) family member NIMA-related kinase 2 (NEK2) plays an important role in mitosis. However, the role of NEK2 in the pathogenesis of ESCC remains unclear. Patients and methodsThe expression and function of NEK2 in TCGA and GEO data sets were analyzed by bioinformatics. We verified the expression of NEK2 in ESCC tissues and cell lines by Western blotting and immunohistochemical methods and further explored the relationship between tumor stage and NEK2 expression. The differences in NEK2 expression and survival in patients with EC were verified by bioinformatics analysis. ESCC cell lines with stable knockdown of NEK2 were established by lentivirus-mediated shRNA delivery. The effects of NEK2 on ESCC cells were analyzed on the cytological level with assays including CCK-8, EdU, cell scratch, Transwell migration and invasion, colony formation, flow cytometry and apoptosis assays. Tumor growth was measured in a mouse xenograft model. ResultsWe found that NEK2 is highly expressed in ESCC tissues and ESCC cells and that the high expression of NEK2 is associated with poor tumor healing. Knockdown of the NEK2 gene inhibits the migration, proliferation, invasion and cell cycle of ESCC cells. Biologic analysis shows that NEK2 is involved in biological processes such as progression and apoptosis of esophageal cancer, and is related to E2F.Mechanistically, NEK2 knockdown decreases the expression levels of E2F1 and IGF2. NEK2 competes with the transcription factor E2F1 to bind CDC20, resulting in decreased degradation and increased expression of E2F1. IGF2 expression is also increased, which promotes the expression of thymidylate synthase, further promoting the drug resistance of ESCC cells. NEK2 is associated with immune infiltration in esophageal cancer. ConclusionNEK2 is highly expressed in ESCC and can promote the migration, proliferation and invasion of ESCC cells. NEK2 mediates ESCC immunotherapy.

Curcumin suppresses the malignant phenotype of laryngeal squamous cell carcinoma through downregulating E2F1 to inhibit FLNA.

Curcumin is a kind of polyphenol substance extracted from the rhizome of Curcuma longa. Because of its good biological activity and pharmacological effects, it has been used in anti-tumor research. The aim of this study was to investigate the anti-cancer mechanism of curcumin on laryngeal squamous cell carcinoma (LSCC). Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to check the expression level of transcription factor E2F1 (E2F1) and filamin A (FLNA) mRNA. E2F1 and FLNA protein and proliferation-associated protein were detected through western blot. Cell viability was showed by MTT assay, and flow cytometry was used to exhibit cell cycle distribution and cell apoptosis. Tube formation assay was used to detect the angiogenesis ability of cells. Transwell was used as a method to observe cell migration and invasion. The online website JASPAR predicted the binding site of E2F1 and FLNA promoter, and chromatin immunoprecipitation (ChIP) and dual-luciferase report experiment verified the combination. Curcumin treatment made LSCC cells viability reduce, cell cycle retardant, angiogenesis decrease, metastasis inhibition and apoptosis increase. And curcumin treatment could downregulate the expression of E2F1, and E2F1 overexpression would reverse the influence of curcumin treatment in LSCC cells. Moreover, E2F1 could bind to FLAN promoter and promote FLNA expression. The expression level of FLNA was higher in LSCC tissue and cells compared with normal tissue and cells. E2F1 knockdown inhibited malignant phenotype of LSCC cells, which would be reversed by FLNA addition. In addition, FLNA had high level in LSCC tissue and cells. Curcumin regulated FLNA expression via inhibiting E2F1. Finally, in vivo assay showed that curcumin inhibition restrained LSCC tumor formation. Curcumin downregulated FLNA expression through inhibiting E2F1, thereby suppressing the malignant phenotype and angiogenesis of LSCC cells, which was a new regulatory pathway in LSCC.

A mRNA panel for differentiation between acute exacerbation or pneumonia in COPD patients.

Patients suffering from chronic obstructive pulmonary disease (COPD) are prone to acute exacerbations (AECOPD) or community acquired pneumonia (CAP), both posing severe risk of morbidity and mortality. There is no available biomarker that correctly separates AECOPD from COPD. However, because CAP and AECOPD differ in aetiology, treatment and prognosis, their discrimination would be important. This study analysed the ability of selected candidate transcripts from peripheral blood mononuclear cells (PBMCs) to differentiate between patients with AECOPD, COPD & CAP, and CAP without pre-existing COPD. In a previous study, we identified differentially regulated genes between CAP and AECOPD in PBMCs. In the present new cohort, we tested the potential of selected candidate PBMC transcripts to differentiate at early time points AECOPD, CAP+COPD, and CAP without pre-existing COPD. Expression of YWHAG, E2F1 and TDRD9 held predictive power: This gene set predicted diseases markedly better (model accuracy up to 100%) than classical clinical markers like CRP, lymphocyte count and neutrophil count (model accuracy up to 82%). In summary, in our cohort expression levels of YWHAG, E2F1 and TDRD9 differentiated with high accuracy between COPD patients suffering from acute exacerbation or CAP.

Abstract 6814: E2F1-induced autocrine IL-6 inflammatory loop mediates cancer-immune cell crosstalk that regulates metastatic properties in melanoma

Abstract Melanoma is a cancer that is metastatic, drug-refractory and fatal if managed late or inadequately. The transcription factor E2F1 is a key player in melanoma pathology, promoting metastatic traits like EMT, neoangiogenesis, chemoresistance and evasion of immune surveillance. Particularly, high levels of E2F1 trigger tumor progression by developing protein-protein interactions (PPI) with coregulators that enhance its potential to activate a prometastatic gene regulatory network (GRN). We aimed to investigate the extent to which E2F1-expressing melanoma cells influence the immune response. Methods: We combined transcriptomic approaches with bioinformatics and structural modeling to search for target genes involved in E2F1-activated immunomodulatory and prometastatic GRNs in aggressive melanoma. Immunoprecipitation and ChIP were performed to verify both PPI and protein-DNA interactions. Functional analyses, including qRT-PCR, immunoblotting and luciferase assays, were performed to verify expression and regulation of downstream targets. Additionally, we established a melanoma-immune cell coculture system with patient-derived CD4+ and CD8+ T cells. Cytokine arrays and ELISA were used for measurement of cytokine secretion to analyze the E2F1-induced tumor-immuno-crosstalk. Results: We identified an E2F1-dependent GRN with IL-6 as a central factor mediating EMT and immune regulation. Mechanistically, E2F1-induced activation and secretion of IL-6 leads to an autocrine inflammatory forward-feedback loop, which in turn further promotes invasiveness and EMT marker expression in melanoma cells. Interestingly, IL6 activated STAT3 associates with E2F1 in a structure-dependent manner, forming a complex that enhances IL-6 expression by binding to a composite E2F1:STAT3-responsive promoter element. Moreover, we observed that the E2F1-IL6 axis dispenses immunomodulatory effects on surrounding CD4+ and CD8+ T cells, further stimulating IL-6 release, but also leading to secretion of IL-10 into the TME. Although IL-10 has an immunosuppressive function, it also showed anti-metastatic properties in melanoma cells. Thus, in contrast to IL-6, IL-10 decreased cell motility and reduced the expression of Vim, Slug, and Snai1, while simultaneous knockdown of E2F1 increased these effects. The findings are supported by clinical data sets showing that melanoma patients who have high levels of E2F1 and IL-6 and low IL-10 exhibit poor survival. Conclusion: Our results unveil a novel gene regulatory program by which E2F1-associated IL-6 release induces the formation of an E2F1:STAT3 complex, resulting in a forward-feedback loop that promotes cancer invasion and regulates T cells response through intercellular cytokine signaling in the tumor microenvironment. Citation Format: Prabir Dhar, Krishna P. Singh, Shailendra K. Gupta, Dhanya Peringot, Alf Spitschak, Brigitte M. Pützer. E2F1-induced autocrine IL-6 inflammatory loop mediates cancer-immune cell crosstalk that regulates metastatic properties in melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6814.

Transcription Factor E2F1 Enhances Hepatocellular Carcinoma Cell Proliferation and Stemness by Activating GINS1.

Present studies report that high expression of GINS complex subunit 1 (GINS1) is notably pertinent to poor survival for hepatocellular carcinoma (HCC), but it remains unclear how GINS1 affects the progression of HCC. This study aims at investigating the mechanism by which GINS1 affects HCC cell proliferation and stemness. We performed bioinformatics analysis for determining GINS1 expression in HCC tissues, as well as the HCC patients' survival rate with different expression levels of GINS1. E2F transcription factor 1 (E2F1) was predicted as the upstream transcription factor of GINS1, and the binding relation between the two was verified by chromatin immunoprecipitation and dual-luciferase reporter assays. Quantitative real-time polymerase chain reaction was adopted to evaluate the expression of GINS1 and E2F1. The protein expression levels of GINS1, E2F1, and cell stemness-related genes (SOX-2, NANOG, OCT4, and CD133) were detected by Western blot. Afterward, the proliferative capacity and stemness of HCC tumor cells were determined through colony formation, cell counting kit-8, and sphere formation assays. Our study found the high expression of GINS1 and E2F1 in HCC, and overexpressed GINS1 markedly enhanced the sphere formation and proliferation of HCC cells, while silencing GINS1 led to the opposite results. Besides, E2F1 promoted the transcription of GINS1 by working as an upstream transcription factor. The results of the rescue experiment suggested that overexpressed E2F1 could offset the suppressive effect of GINS1 silencing on HCC cell stemness and proliferation. We demonstrated that the transcription factor E2F1 accelerated cell proliferation and stemness in HCC by activating GINS1 transcription. The results can provide new insight into the GINS1-related regulatory mechanism in HCC, which suggest that it may be an effective way for HCC treatment by targeting the E2F1/GINS1 axis.

Investigating the potential hub genes and mechanisms of Artemisia annua L. against breast cancer based on network pharmacology and molecular docking

Artemisia annua L. has been revealed to possess antitumor effect in various human cancers. However, the mechanism of A. annua treating breast cancer (BRCA) has not been clearly elucidated. In present study, the bioactive compounds and mechanism of A. annua in the treatment of BRCA were explored based on network pharmacology and molecular docking. TCMSP database was used to predict the active components and components targets of A. annua. The targets of BRCA were collected through TTD, GeneCards, OMIM, PharmGKB and DisGeNET database. The analysis of GO and KEGG enrichment was conducted for intersection targets. Protein–Protein interaction (PPI) network was constructed using the STRING online database. Candidate core targets were screened using the gene expression analysis and survival analysis. Molecular docking analysis was conducted to verify whether the bioactive compounds had a definite affinity with candidate core targets. Finally, MTT and RT-qPCR experiments of MCF-7 cells and MDA-MB-231 cells were carried out to verify the results of network pharmacology.The quercetin, luteolin, kaempferol were selected as hub compounds of A. annua against BRCA. After the conduction of topological analysis, survival analysis, and gene expression analysis for the potential targets of A. annua against BRCA, 4 candidate hub targets (BICR5, CCNA2, E2F1 and FOS) were identified. Molecular docking results demonstrated that 3 hub components of A. annua had strong binding efficiency with the 4 candidate hub targets. The enrichment analysis of KEGG pathway revealed that A. annua exerted anti-BRCA effects via p53 signaling pathway, etc. After treated with total flavonoids of A. annua (ATF) for 48 h, mRNA expression levels of BICR5, CCNA2, E2F1 and FOS were significantly down-regulated in both MCF-7 cells and MDA-MB-231 cells. The present study reveals the mechanism of A. annua against BRCA through multiple targets, multiple ingredients and multiple signal pathways, and provides more references for its clinical application.

The long non-coding RNA TAZ-AS202 promotes lung cancer progression via regulation of the E2F1 transcription factor and activation of Ephrin signaling

Long non-coding RNAs (lncRNAs) are transcripts without coding potential that are pervasively expressed from the genome and have been increasingly reported to play crucial roles in all aspects of cell biology. They have been also heavily implicated in cancer development and progression, with both oncogenic and tumor suppressor functions. In this work, we identified and characterized a novel lncRNA, TAZ-AS202, expressed from the TAZ genomic locus and exerting pro-oncogenic functions in non-small cell lung cancer. TAZ-AS202 expression is under the control of YAP/TAZ-containing transcriptional complexes. We demonstrated that TAZ-AS202 is overexpressed in lung cancer tissue, compared with surrounding lung epithelium. In lung cancer cell lines TAZ-AS202 promotes cell migration and cell invasion. TAZ-AS202 regulates the expression of a set of genes belonging to cancer-associated pathways, including WNT and EPH-Ephrin signaling. The molecular mechanism underlying TAZ-AS202 function does not involve change of TAZ expression or activity, but increases the protein level of the transcription factor E2F1, which in turn regulates the expression of a large set of target genes, including the EPHB2 receptor. Notably, the silencing of both E2F1 and EPHB2 recapitulates TAZ-AS202 silencing cellular phenotype, indicating that they are essential mediators of its activity. Overall, this work unveiled a new regulatory mechanism that, by increasing E2F1 protein, modifies the non-small cell lung cancer cells transcriptional program, leading to enhanced aggressiveness features. The TAZ-AS202/E2F1/EPHB2 axis may be the target for new therapeutic strategies.

TP53/mTORC1-mediated bidirectional regulation of PD-L1 modulates immune evasion in hepatocellular carcinoma

BackgroundImmunotherapy has facilitated great breakthroughs in the treatment of hepatocellular carcinoma (HCC). However, the efficacy and response rate of immunotherapy are limited and vary among different patients with HCC. TP53...

Abstract 5979: TY-0540, a highly potent CDK2/4/6 inhibitor, attenuates acquired resistance against CDK4/6 inhibition

Abstract The introduction of cyclin-dependent kinase (CDK) 4 and 6 dual inhibitors significantly improves the progression-free survival of patients with ER+/HER2- advanced or metastatic breast cancer. A large cohort of patients, however, eventually relapse to CDK4/6 therapy. To further empower the CDK therapy, simultaneous targeting of CDK2, CDK4, and CDK6 has been proposed as a new strategy based on the finding that abnormal activation of CDK2/CyclinE1 due to CCNE1 gene amplification is determined the key resistant mechanism to CDK4/6 inhibition. Here we present preclinical data of TY-0540, a novel CDK2/4/6 inhibitor for the treatment of breast cancer that is resistant to CDK4/6 inhibition. TY-0540 demonstrates high selectivity against CDK2, CDK4, and CDK6 compared to that of CDK1, CDK7, and CDK9 in a CDK panel screening. In vitro cell proliferation data shows that tumor cell lines OVCAR3 and HCC1806, both bearing CCNE1 amplification, are highly sensitive to TY-0540 treatment. To test the effectiveness of the clinical candidate compound on CDK4/6i resistance models, two Palbociclib resistant cell populations (T47D-R, HCC1428-R) were in-house generated via gradient exposure of the cells to Palbociclib. As expected, TY-0540 potently inhibits T47D-R and HCC1428-R cell proliferation whereas Palbociclib only confers mild interruption to cell proliferation. TY-0540 abolishes Rb phosphorylation at all its three phosphorylation sites and down-regulates E2F1, FOXM1, and c-Myc expression levels in the model cell line OVCAR3. Meanwhile, cell cycle analysis suggests the occurrence of strong G1 arrest at 24 hours after TY-0540 treatment. Consistent with the in vitro results, TY-0540 treatment confers extraordinary in vivo efficacy with a spectrum of tumor CDX mouse models and PDX models in mice. To examine the in vivo effectiveness of TY-0540 over resistance models to CDK4/6 inhibition, we developed Palbociclib-resistant MCF7 tumor model (Palbociclib-R-MCF7) through a combination of in vitro and in vivo evolution of the cells under the selection pressure of Palbociclib. In agreement with its mode of action, TY-0540 is able to suppress Palbociclib-R-MCF7 tumor growth and maintain tumor size at stable disease status. Taken together, we have identified a potent CDK2/4/6 inhibitor which may grant new therapeutic opportunities for cancer patients who relapse or refractory to CDK4/6 signaling blockage therapy. #Meihua Li and Chengshan Niu contributed equally to this work. *Jun Li, Meihua Li and Chengshan Niu are the correspondent authors. Citation Format: Meihua Li, Chengshan Niu, Mingtao Chen, Kaige Ji, Hui Xu, Shengli Dong, Yan Zhang, Qinguo Meng, Yuge Dou, Yijun Wang, Rui Wu, Yian Tu, Chao Zhou, Apeng Liang, Huan Wang, Rongzhen Ni, Aishen Gong, Hui Su, Mingyu Jiang, Feng Xing, Shaoqing Chen, Xiugui Chen, Jun Li, Yusheng Wu. TY-0540, a highly potent CDK2/4/6 inhibitor, attenuates acquired resistance against CDK4/6 inhibition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5979.

PDZ-binding kinase inhibitor OTS514 suppresses the proliferation of oral squamous carcinoma cells.

PDZ-binding kinase (PBK) has been reported as a poor prognostic factor and is a promising molecular target for anticancer therapeutics. Here, we aimed to investigate the effect of specific PBK inhibitor OTS514 on the survival of OSCC cells. Four OSCC cell lines (HSC-2, HSC-3, SAS, and OSC-19) were used to examine the effect of OTS514 on cell survival and apoptosis. DNA microarray analysis was conducted to investigate the effect of OTS514 on gene expression in OSCC cells. Gene set enrichment analysis was performed to identify molecular signatures related to the antiproliferative effect of OTS514. OTS514 decreased the cell survival of OSCC cells dose-dependently, and administration of OTS514 readily suppressed the HSC-2-derived tumor growth in immunodeficient mice. Treatment with OTS514 significantly increased the number of apoptotic cells and caspase-3/7 activity. Importantly, OTS514 suppressed the expression of E2F target genes with a marked decrease in protein levels of E2F1, a transcriptional factor. Moreover, TP53 knockdown attenuated OTS514-induced apoptosis. OTS514 suppressed the proliferation of OSCC cells by downregulating the expression of E2F target genes and induced apoptosis by mediating the p53 signaling pathway. These results highlight the clinical application of PBK inhibitors in the development of molecular-targeted therapeutics against OSCC.

HMSH2 coordinated with the expression of E2F1 promotes platinum response in epithelial ovarian cancer

To explore underlying mechanisms that regulate hMSH2 expression and drug susceptibility in epithelial ovarian cancer (EOC). Using data from the Cancer Genome Atlas (TCGA) we used bioinformatical analysis to predict transcription factors (TFs) that potentially regulate hMSH2. RT-qPCR, Western blot, and luciferase assays were undertaken using ovarian cancer cell lines to verify the identified TF. Expressions of the TF were modulated using overexpression or knockdown, and the corresponding cellular responses to cisplatin were examined. The TF, E2F1, was found to regulate the hMSH2 gene. The expression level of E2F1 correlated with cisplatin susceptibility in vitro. Kaplan-Meier analysis of 77 patients with EOC showed that low E2F1 expression was associated with worse survival. To our knowledge, this is the first report of E2F1 regulated MSH2 expression playing a role in drug resistance of platinum-based treatments for patients with EOC. Further work is need to confirm our results.

Long non-coding RNA-derived peptides are immunogenic and drive a potent anti-tumour response

Protein arginine methyltransferase (PRMT) 5 is over-expressed in a variety of cancers and the master transcription regulator E2F1 is an important methylation target. We have explored the role of PRMT5 and E2F1 in regulating the non-coding genome and report here a striking effect on long non-coding (lnc) RNA gene expression. Moreover, many MHC class I protein-associated peptides were derived from small open reading frames in the lncRNA genes. Pharmacological inhibition of PRMT5 or adjusting E2F1 levels qualitatively altered the repertoire of lncRNA-derived peptide antigens displayed by tumour cells. When presented to the immune system as either ex vivo-loaded dendritic cells or expressed from a viral vector, lncRNA-derived peptides drove a potent antigen-specific CD8 T lymphocyte response, which translated into a significant delay in tumour growth. Thus, lncRNA genes encode immunogenic peptides that can be deployed as a cancer vaccine.

Docetaxel Enhances Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand-Mediated Apoptosis in Prostate Cancer Cells via Epigenetic Gene Regulation by Enhancer of Zeste Homolog 2.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising cancer therapeutic agent because of its tumor selectivity and its ability to induce apoptosis in cancer cells while sparing most normal cells. We evaluated whether docetaxel enhances TRAIL-mediated apoptosis in prostate cancer (PCa) cells and its mechanism. LNCap-LN3, PC3, and DU 145 PCa cell lines were used to investigate the effects of TRAIL with docetaxel treatment (dosages, 1, 3, 5, and 10 nmol). To evaluate the mechanism, death receptor 4 (DR4), DR5, enhancer of zeste homolog 2 (EZH2) and E2F1 levels were assessed in PCa cells. Hormone-sensitive LNCap-LN3 showed apoptosis in proportion to the concentration of docetaxel. Castration-resistant PC3 and DU 145 showed no change irrespective of the docetaxel concentration. However, combinations of docetaxel (2 nM) and TRAIL (100 ng/mL) had a significant effect on apoptosis of DU 145 cells. In DU 145 cells, docetaxel reduced EZH2 and elevated expression of DR4. The decrease of EZH2 by docetaxel was correlated with the E2F1 level, which was considered as the promoter of EZH2. DZNep reduced EZH2 and elevated DR4 in all PCa cells. Additionally, DZNep-enhanced TRAIL mediated reduction of PCa cell viability. Docetaxel and the EZH2 inhibitor reduced EZH2 and elevated expression of DR4 in all PCa cell lines. Docetaxel-enhanced TRAIL mediated apoptosis in PCa via elevation of DR4 through epigenetic regulation by EZH2. To improve the efficacy of TRAIL for PCa treatment, adding docetaxel or EZH2 inhibitors to TRAIL may be promising.

MiRNA-329-3p suppresses proliferation and metastasis of endometrial carcinoma through downregulating E2F1.

Existing evidences have revealed the crucial roles of E2 promoter binding factor-1 (E2F1) during the tumorigenesis and progression process of multiple human tumors. However, the expression patterns, biological functions, as well as the underlying molecular mechanism of E2F1 in endometrial carcinoma yet remain largely unclear. The expression patterns and clinical prognostic value of E2F1 in endometrial carcinoma were evaluated using bioinformatics methods. Protein and mRNA, miRNA expression levels in tissues and cells were measured using immunohistochemistry, western blotting, and qRT-PCR assays. Cell viability and cell cycle distribution were examined using CCK-8 assay and flow cytometry, respectively. Scratch healing assay and Transwell assay were applied to measure cell migration and invasion ability. Bioinformatic analysis and luciferase reporter assays were conducted to confirm the targeting relationship between E2F1 and miR-329-3p. Moreover, a series of in vitro and in vivo functional experiments were employed to evaluate the effect of the miR-329-3p/E2F1 axis on cell growth and metastasis. Clinically, E2F1 was aberrantly expressed in endometrial carcinoma tissues and was correlated with advanced FIGO stage, histological type, p53 mutation, poor survival, and degree of tumor cell differentiation. ROC curves analysis also reveals that E2F1 has a high AUC value (up to 0.952, 95% CI: 0.915-0.988), indicating the promising diagnostic value of E2F1 level in endometrial carcinoma. In addition, in vitro gain and loss-of-functional experiments verified that high E2F1 can promote cell proliferation, cell cycle, migration, invasion, and EMT process. In-depth mechanism studies revealed that E2F1 was a downstream target gene of miR-329-3p, and miR-329-3p overexpression could effectively abrogate its promotion of cell malignant biological behavior. Collectively, our findings suggested that the miR-329-3p/E2F1 axis plays a crucial role in the progression of endometrial carcinoma, indicating that E2F1 can be considered a promising diagnostic and prognostic biomarker for endometrial carcinoma patients.

The role of PI3K/AKT-related proteins in di(2-ethyl)hexylphthalate-induced BG-1 and MCF-7 cell proliferation, and inhibition by metformin

Objective To investigate the molecular mechanism of the proliferation and migration of BG-1 and MCF-7cells induced by DEHP, and the antagonistic effect of metformin. Methods The proliferation, cell cycle progression, migration, and invasion abilities of BG-1 and MCF-7 cancer cells were examined via Cell Counting Kit-8, flow cytometry, Transwell, and scratch assays. E2F1, SKP2, cyclin D1, vimentin, E-cadherin, and GSK-3β, all of which play key roles in cancer development via the PI3K/AKT signaling pathway, were examined by immunofluorescence and immunocytochemistry. Results Cell proliferation was significantly increased, and the wound closure and number of trans-membrane migrating cells were significantly increased, by DHEP treatment. The numbers of BG-1 and MCF-7 cells in the G0/G1 phase were significantly decreased, while those in the S phase were significantly increased. Increased E2F1, SKP2, cyclin D1, and vimentin levels and decreased E-cadherin and GSK-3β levels were detected in BG-1 and MCF-7 cells treated with DEHP compared to that in control cells. Furthermore, DEHP-induced effects were markedly inhibited by LY294002 (a PI3K/AKT inhibitor) or metformin. Conclusion We demonstrated that DEHP-induced cell proliferation and migration involves the PI3K/AKT signaling pathway and that metformin can be used to inhibit this proliferation and migration.

Construction of Oxidative Stress-Related Genes Risk Model Predicts the Prognosis of Uterine Corpus Endometrial Cancer Patients.

Oxidative stress contributes significantly to cancer development. Recent studies have demonstrated that oxidative stress could alter the epigenome and, in particular, DNA methylation. This study aimed to explore the potential link between oxidative stress and uterine corpus endometrial carcinoma (UCEC). An analysis of RNA-seq data and relevant clinical information was conducted with data from The Cancer Genome Atlas (TCGA), and oxidative stress genes were obtained from Gene Set Enrichment Analysis (GSEA). Differentially expressed genes (DEGs) in normal and tumor groups of UCEC were analyzed using GO and KEGG enrichment analysis. As a result of survival analysis, Lasso regression analysis of DEGs, a risk score model of oxidative stress-related genes (OSRGs) was constructed. Moreover, this study demonstrated that OSRGs are associated with immune cell infiltration in UCEC, suggesting oxidative stress may play a role in UCEC development by activating immune cells. We discovered 136 oxidative stress-related DEGs in UCEC, from which we screened 25 prognostic genes significantly related to the overall survival of UCEC patients. BCL2A1, CASP6, GPX2, HIC1, IL19, MSX1, RNF183, SFN, TRPM2 and HIST1H3C are associated with a good prognosis while CDKN2A, CHAC1, E2F1, GSDME, HMGA1, ITGA7, MCM4, MYBL2, PPIF, S100A1, S100A9, STK26 and TRIB3 are involved in a poor prognosis in UCEC. A 7-OSRGs-based risk score (H3C1, CDKN2A, STK26, TRPM2, E2F1, CHAC1, MSX1) was generated by Lasso regression. Further, an association was found between H3C1, CDKN2A, STK26, TRPM2, E2F1, CHAC1 and MSX1 expression levels and the immune infiltrating cells, including CD8 T cells, NK cells, and mast cells in UCEC. NFYA and RFX5 were speculated as common transcription factors of CDKN2A, TRPM2, E2F1, CHAC1, and MSX1 in UCEC.

E2F1 promotes cell cycle progression by stabilizing spindle fiber in colorectal cancer cells

BackgroundE2F1 is a transcription factor that regulates cell cycle progression. It is highly expressed in most cancer cells and activates transcription of cell cycle-related kinases. Stathmin1 and transforming acidic coiled-coil-containing protein 3 (TACC3) are factors that enhance the stability of spindle fiber.MethodsThe E2F1-mediated transcription of transforming acidic coiled-coil-containing protein 3 (TACC3) and stathmin1 was examined using the Cancer Genome Atlas (TCGA) analysis, quantitative polymerase chain reaction (qPCR), immunoblotting, chromatin immunoprecipitation (ChIP), and luciferase reporter. Protein–protein interaction was studied using co-IP. The spindle structure was shown by immunofluorescence. Phenotype experiments were performed through MTS assay, flow cytometry, and tumor xenografts. Clinical colorectal cancer (CRC) specimens were analyzed based on immunohistochemistry.ResultsThe present study showed that E2F1 expression correlates positively with the expression levels of stathmin1 and TACC3 in colorectal cancer (CRC) tissues, and that E2F1 transactivates stathmin1 and TACC3 in CRC cells. Furthermore, protein kinase A (PKA)-mediated phosphorylation of stathmin1 at Ser16 is essential to the phosphorylation of TACC3 at Ser558, facilitating the assembly of TACC3/clathrin/α-tubulin complexes during spindle formation. Overexpression of Ser16-mutated stathmin1, as well as knockdown of stathmin1 or TACC3, lead to ectopic spindle poles including disorganized and multipolar spindles. Overexpression of wild-type but not Ser16-mutated stathmin1 promotes cell proliferation in vitro and tumor growth in vivo. Consistently, a high level of E2F1, stathmin1, or TACC3 not only associates with tumor size, lymph node metastasis, TNM stage, and distant metastasis, but predicts poor survival in CRC patients.ConclusionsE2F1 drives the cell cycle of CRC by promoting spindle assembly, in which E2F1-induced stathmin1 and TACC3 enhance the stability of spindle fiber.