ELF5 in epithelial ovarian carcinoma tissues and biological behavior in ovarian carcinoma cells

ELF5-Regulated lncRNA-TTN-AS1 Alleviates Myocardial Cell Injury via Recruiting PCBP2 to Increase CDK6 Stability in Myocardial Infarction

Myocardial infarction (MI) seriously threatens the health of elderly people, and reducing myocardial injury is of great significance for the treatment of MI. LncRNA-TTN-AS1 shows protective effects on cardiomyocyte injury, while the role of TTN-AS1 in MI remains unknown. CCK8, flow cytometry, and JC-1 staining assessed cell viability, apoptosis and mitochondrial membrane potential (MMP), respectively. Cellular reactive oxygen species (ROS) and secreted lactate dehydrogenase (LDH) levels were measured. The interactions between ELF5, TTN-AS1, PCBP2 and CDK6 were explored using ChIP, luciferase reporter assay, RIP, and pull-down. The severity of MI in mice was evaluated using TTC, H&E, and TUNEL staining. The data revealed that OGD/R significantly induced ROS, mitochondrial injury and apoptosis in AC16 cells, while overexpression of ELF5 or TTN-AS1 reversed these phenomena. ELF5 transcriptionally activated TTN-AS1 through binding with its promoter. TTN-AS1 increased CDK6 stability via recruiting PCBP2. CDK6 knockdown abolished the inhibitory effects of TTN-AS1 overexpression on OGD/R-induced myocardial injury. Furthermore, overexpression of TTN-AS1 or ELF5 alleviated MI progression in mice by upregulating CDK6. Collectively, TTN-AS1 transcriptionally regulated by ELF5 alleviated myocardial apoptosis and injury during MI via recruiting PCBP2 to increase CDK6 stability, which shed new lights on exploring new strategies against MI.

ELF5: A Molecular Clock for Breast Aging and Cancer Susceptibility

Breast cancer is predominantly an age-related disease, with aging serving as the most significant risk factor, compounded by germline mutations in high-risk genes like BRCA1/2. Aging induces architectural changes in breast tissue, particularly affecting luminal epithelial cells by diminishing lineage-specific molecular profiles and adopting myoepithelial-like characteristics. ELF5 is an important transcription factor for both normal breast and breast cancer development. This review focuses on the role of ELF5 in normal breast development, its altered expression throughout aging, and its implications in cancer. It discusses the lineage-specific expression of ELF5, its regulatory mechanisms, and its potential as a biomarker for breast-specific biological age and cancer risk.

E74‑like ETS transcription factor 5 facilitates cell proliferation through regulating the expression of adenomatous polyposis coli 2 in non‑small cell lung cancer

E74‑like ETS transcription factor 5 (ELF5) is known to regulate the specification and differentiation of epithelial cells in the embryonic lung. However, the pathological function of ELF5 in lung cancer has yet to be fully elucidated. In the present study, the expression of ELF5 was found to be significantly higher in lung adenocarcinoma compared with that in corresponding adjacent normal tissues. Subsequently, cell and animal experiments were performed to investigate the role of ELF5 in lung adenocarcinoma cells. The results indicated that the overexpression of ELF5 increased the proliferation of lung adenocarcinoma cells, whereas, by contrast, a reduction in the expression of ELF5 led to a decrease in their proliferation. Mechanistically, the hypothesis is advanced that ELF5 can promote lung cancer cell proliferation through inhibiting adenomatous polyposis coli 2 and increasing the expression of cyclin D1, which is a critical downstream target of the Wnt pathway. Taken together, these findings support the notion that ELF5 exerts an essential role in the proliferation of lung adenocarcinoma cells and may be a therapeutic target for the treatment of lung adenocarcinoma.

ELF5 inhibits the proliferation and invasion of breast cancer cells by regulating CD24

E74-like factor five (ELF5) is a basic transcription factor that plays a key role in breast tissue and gland development. However, the molecular mechanism of ELF5 in breast cancer cells has not been elucidated. In this study, we examined the effect of ELF5 on the human breast cancer cell lines MCF-7 and T47D and confirmed that ELF5 can inhibit cell proliferation, migration and invasion. In further research, the relationship between ELF5 and CD24 was characterized in breast cancer cells. We found that CD24 was a target gene of ELF5 through chromatin immunoprecipitation (ChIP) -Sequence assays, and proved that ELF5 could bind to the ETS cis-element on the proximal promoter of the CD24 gene and regulate the expression of CD24. Moreover, overexpression of ELF5 in MCF-7 cells significantly increased both the mRNA and protein levels of CD24, while knockdown of CD24 expression restored cell proliferation, migration and invasion through adaptive ELF5 expression in MCF-7 cells. Therefore, these data suggest that ELF5 inhibits migration and invasion of breast cancer cells by regulating CD24 expression, which make provides a molecular mechanism for ELF5 to inhibit breast cancer from a new perspective and provides further theoretical support for the treatment and prevention of breast cancer.

[In vivo and in vitro Experiment of E74-Like Factor 5 Overexpression Inhibiting the Biological Behavior of Colon Cancer Cells]

OBJECTIVE

To investigate the effect of E74-like factor 5 (ELF5) overexpression on the growth and invasion ability of colorectal cancer cells and its effect on tumor formation in nude mice.

METHODS

Human colorectal cancer SW480 and HT-29 cells were divided into 5 groups: the lentivirus (LV)- GFP group transfected with empty vector LV- GFP, the LV- ELF5 group transfected with recombinant LV- ELF5, the shRNA-NC group transfected with empty vector shRNA-NC, the shRNA- ELF5 group transfected with recombinant shRNA- ELF5, and the control group, not transfected with any vector. Seventy-two h after transfection, the cell supernatant containing lentivirus was collected. The mRNA expression level of ELF5 in each group was examined by real-time fluorescent quantitative PCR (RT-qPCR). The protein expression levels of ELF5, apoptosis-related cleaved Caspase-3/Caspase-3 and cleaved Caspase-9/Caspase-9, and invasion-related E-cadherin and N-cadherin were checked with Western blot. CCK-8 was used to check cell viability. Colony formation experiment was done to evaluate colony formation rate. Flow cytometry was used to assess cell apoptosis. Transwell migration assay was used to examine cell invasion. TUNEL assay was used to examine the apoptosis of tissues cells. Immunohistochemistry test was done to determine the expression of E-cadherin and N-cadherin in tissues. 20 BALB/c nude mice were put into 4 groups (5 in each group): LV- GFP group, shRNA-NC group, LV- ELF5 group, and shRNA- ELF5 group. Recombinant lentiviral SW480 cell supernatants were subcutaneously injected into nude mice to construct nude mice tumorigenesis models and the volume changes of transplanted tumors were monitored. On the 30th day, transplanted tumor tissues from the nude mice were extracted and the tumor mass was measured. Western blot was done to measure the expression of ELF4 protein in the transplanted tumors. TUNEL staining was used to check cell apoptosis in the tissues, and the positive expression of N-cadherin in the transplanted tumor was measured by immunohistochemical tests.

RESULTS

Compared with the control group, there was no statistically significant difference in the indicators of the two cell lines in the LV- GFP group and shRNA-NC group. The results of Western blot and RT-qPCR showed that the ELF5 protein and mRNA of the LV- ELF5 group of the two cell lines were up-regulated ( P<0.05, compared with those of the LV- GFP group), and the ELF5 protein and mRNA of the shRNA- ELF5 group were down-regulated ( P<0.05). The ELF5 overexpression system and interference system were successfully constructed. Compared with the LV- GFP group, data from the LV- ELF5 group showed that cell viability and colony formation rate ( P<0.05) were reduced, SW480 and HT-29 cell apoptosis was promoted, cleaved Caspase-3/Caspase-3 and cleaved Caspase-9/Caspase-9 protein expression was up-regulated ( P<0.05), cell invasion was inhibited, and the expression of E-cadherin protein was up-regulated while the expression of N-cadherin protein was down-regulated ( P<0.05). After ELF5 interference, the above-mentioned expression of cells demonstrated an opposite trend ( P<0.05, comparing shRNA- ELF5 group with shRNA-NC group). In vivo experimental results indicated that ELF5 overexpression reduced tumor volume and tumor mass ( P<0.05), promoted cell apoptosis in tissues ( P<0.05), and inhibited N-cadherin protein expression ( P<0.05). When ELF5 expression was inhibited, the above mentioned experimental results showed the opposite trend.

CONCLUSION

In vivo and in vitro experiments showed that ELF5 overexpression could promote the apoptosis of colorectal cancer cells and inhibit the growth and invasion of colorectal cancer cells.

Acetylation of ELF5 suppresses breast cancer progression by promoting its degradation and targeting CCND1

E74-like ETS transcription factor 5 (ELF5) is involved in a wide spectrum of biological processes, e.g., mammogenesis and tumor progression. We have identified a list of p300-interacting proteins in human breast cancer cells. Among these, ELF5 was found to interact with p300 via acetylation, and the potential acetylation sites were identified as K130, K134, K143, K197, K228, and K245. Furthermore, an ELF5-specific deacetylase, SIRT6, was also identified. Acetylation of ELF5 promoted its ubiquitination and degradation, but was also essential for its antiproliferative effect against breast cancer, as overexpression of wild-type ELF5 and sustained acetylation-mimicking ELF5 mutant could inhibit the expression of its target gene CCND1. Taken together, the results demonstrated a novel regulation of ELF5 as well as shedding light on its important role in modulation of breast cancer progression.

Expression and clinical significance of WWOX, Elf5, Snail1 and EMT related factors in epithelial ovarian cancer

Expression and clinical significance of WW domain-containing oxidoreductase (WWOX), Elf5, Snail1 and epithelial-mesenchymal transition (EMT) related factors in epithelial ovarian cancer were investigated. Ovarian cancer tissues of 300 epithelial ovarian cancer patients and the adjacent normal tissues were analyzed. Immunohistochemical method was used to detect the expressions of WWOX, Elf5, Snail1 and EMT marker molecules in the specimens. The relationship between the indicators and clinicopathological parameters, and prognosis of patients with ovarian cancer was analyzed. The relationship between WWOX, Elf5, Snail1 and EMT marker molecules E-cadherin, N-cadherin and vimentin in ovarian cancer tissues was analyzed. The expression levels of WWOX, Elf5, Snail1 and EMT marker molecules in epithelial ovarian cancer tissues were significantly different from those in adjacent normal tissues, and were related to surgical pathological stage, pathological grade and lymph node metastasis. High expressions of WWOX and Elf5 were related to the survival rate of patients. The survival rate of patients with positive expression was significantly higher than that of negative expression. FIGO stage, pathological grade, lymph node metastasis and expression of WWOX and Elf5 were all independent factors affecting postoperative prognosis in ovarian cancer patients. In conclusion, the expression levels of WWOX, Elf5, Snail1 and EMT related factors in epithelial ovarian cancer tissues are consistent and different. The expression levels of WWOX and Elf5 are related to the survival and prognosis of patients with epithelial ovarian cancer.

A new Elf5Cre ERT 2- GFP BAC transgenic mouse model for tracing Elf5 cell lineages in adult tissues

Elf5 is a transcription factor known to regulate critical developmental processes and has been shown to act as a tumour suppressor in multiple cancers. Elf5 knockout mice are embryonically lethal, limiting in vivo studies pertaining to its function. Moreover, haploinsufficiency of Elf5 limits the use of current mouse models to investigate adult tissue distribution of Elf5. Here, we successfully generated Elf5^{Cre ERT 2- GFP} bacterial artificial chromosome (BAC) transgenic mice and show that Elf5⁺ cells are present in several adult tissues, where its expression was previously not known. Our study demonstrates the unique distribution of Elf5⁺ cells in multiple adult organs, which will facilitate future studies investigating the function of Elf5 in these tissues during homeostasis, repair and cancer.

Overexpression of E74-Like Factor 5 (ELF5) Inhibits Migration and Invasion of Ovarian Cancer Cells

Background

E74-like factor 5 (ELF5) plays a key role in the processes of cell differentiation, apoptosis, and occurrence of tumors. However, the effect of ELF5 on metastasis and invasion in human ovarian cancer remains poorly understood.

Material/Methods

Quantitative real-time polymerase chain reaction (qPCR) was performed to measure the expression of ELF5. The viability of cells was detected by cell counting kit (CCK-8). Cell apoptosis was tested by flow cytometry. Matrigel plug angiogenesis assay was employed to determine angiogenesis rate. The protein expression levels of vascular endothelial growth factor (VEGF), cleaved caspase-3, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), E-cadherin, N-cadherin, Snail, phosphoinositide 3 kinase (PI3K), phosphorylated (p)-PI3K, tyrosine kinase B (AKT), and phosphorylated (p)-AKT were determined by Western blot. Wound-healing assay and Transwell were used to determine invasion and migration.

Results

We found that expression of ELF5 was obviously decreased in ovarian cancer cell lines. The cells viability, invasion and metastasis were inhibited by overexpression ELF5. ELF5 suppressed angiogenesis rate and the expression of VEGF. Changes of the expressions of Bcl-2, cleaved caspase-3 and Bax showed that anti-apoptosis ability was improved by ELF5. ELF5 also repressed N-cadherin and Snail and increased E-cadherin. The expressions of p-PI3K and p-AKT were decreased by ELF5. Further study showed that IGF-I reversed the inhibitory effect of ELF5 on growth and metastasis of SKOV3 cells.

Conclusions

Overexpression of ELF5 promoted the apoptosis and reduced the migration and invasion of ovarian cancer cells; therefore, it could provide a new approach to gene treatment of ovarian carcinoma.

ELF3, ELF5, EHF and SPDEF Transcription Factors in Tissue Homeostasis and Cancer

The epithelium-specific ETS (ESE) transcription factors (ELF3, ELF5, EHF and SPDEF) are defined by their highly conserved ETS DNA binding domain and predominant epithelial-specific expression profile. ESE transcription factors maintain normal cell homeostasis and differentiation of a number of epithelial tissues, and their genetic alteration and deregulated expression has been linked to the progression of several epithelial cancers. Herein we review the normal function of the ESE transcription factors, the mechanisms by which they are dysregulated in cancers, and the current evidence for their role in cancer progression. Finally, we discuss potential therapeutic strategies for targeting or reactivating these factors as a novel means of cancer treatment.

Expression of ELF5 in endometrial carcinoma tissues and its clinical significance

Expression of E74-like factor 5 (ELF5) in endometrial carcinoma tissues and its clinical significance were investigated. Eighty-four endometrial carcinoma tissues, 30 cases of atypical hyperplasia of endometrium and 30 cases of normal endometrial tissues were selected. Immunohistochemical method was utilized to detect the expression of ELF5 in different endometrial tissues. Moreover, its correlation with clinical pathological indexes of patients with endometrial carcinoma was analyzed. The postoperative follow-up was conducted in all the patients with endometrial carcinoma until June 30th, 2017. The Kaplan-Meier method was used for survival analysis so as to analyze the association of ELF5 expression level with clinical pathological indexes; Cox's proportional hazards regression model was utilized for univariate and multivariate analyses to screen independent risk factors for prognosis of endometrial carcinoma. In normal endometrial tissues, atypical hyperplasia and endometrial carcinoma tissues, the positive expression rates of ELF5 showed a decreased tendency (P=0.016). The positive expression rate of ELF5 in endometrial carcinoma tissues was lower in comparison to normal endometrial tissues (P=0.016). The expression of ELF5 was in accordance with the International Federation of Gynecology and Obstetrics (FIGO) staging of endometrial carcinoma (P<0.05), pathological grading (P<0.05), pathological typing (P=0.001), state of lymph node metastasis (P<0.05) and depth of myometrial invasion (P<0.05). Kaplan-Meier method for survival analysis showed that the average survival time of patients with negative ELF5 expression was shorter in comparison to the patients with positive expression (P=0.004). FIGO staging (P=0.004), pathological grading (P=0.048), depth of myometrial invasion (P=0.024) and lymph node metastasis (P=0.020) were related to the prognosis of patients with endometrial carcinoma, The univariate Cox's regression model analysis indicated that FIGO staging (P=0.010), pathological grading (P=0.040), depth of myometrial invasion (P=0.037), lymph node metastasis (P=0.029) and ELF5 (P=0.010) were associated with the prognosis of patients with endometrial carcinoma. Further, multivariate analysis revealed that ELF5 was an independent risk factor for prognosis of patients with endometrial carcinoma (P=0.035). The expression of ELF5 has a correlation with the occurrence, development and prognosis of endometrial carcinoma.