NEDD4L-induced ubiquitination mediating UBE2T degradation inhibits progression of lung adenocarcinoma via PI3K-AKT signaling

Multi-Omics Characterization of E3 Regulatory Patterns in Different Cancer Types

Ubiquitination, a post-translational modification, refers to the covalent attachment of ubiquitin molecules to substrates. This modification plays a critical role in diverse cellular processes such as protein degradation. The specificity of ubiquitination for substrates is regulated by E3 ubiquitin ligases. Dysregulation of ubiquitination has been associated with numerous diseases, including cancers. In our study, we first investigated the protein expression patterns of E3 ligases across 12 cancer types. Our findings indicated that E3 ligases tend to be up-regulated and exhibit reduced tissue specificity in tumors. Moreover, the correlation of protein expression between E3 ligases and substrates demonstrated significant changes in cancers, suggesting that E3-substrate specificity alters in tumors compared to normal tissues. By integrating transcriptome, proteome, and ubiquitylome data, we further characterized the E3-substrate regulatory patterns in lung squamous cell carcinoma. Our analysis revealed that the upregulation of the SKP2 E3 ligase leads to excessive degradation of BRCA2, potentially promoting tumor cell proliferation and metastasis. Furthermore, the upregulation of E3 ubiquitin-protein ligase TRIM33 was identified as a biomarker associated with a favorable prognosis by inhibiting the cell cycle. This work exemplifies how leveraging multi-omics data to analyze E3 ligases across various cancers can unveil prognosis biomarkers and facilitate the identification of potential drug targets for cancer therapy.

Advances of E3 ligases in lung cancer

Lung cancer is a leading cause of cancer-related death, and the most common type of lung cancer is non-small cell lung cancer, which accounts for approximately 85 % of lung cancer diagnoses. Recent studies have revealed that ubiquitination acts as a crucial part of the development and progression of lung cancer. The E1-E2-E3 three-enzyme cascade has a core function in ubiquitination, so targeted adjustments of E3 ligases could be used in lung cancer treatment. Hence, we elucidate research advances in lung cancer-related E3 ligases by briefly describing the structure and categorization of E3 ligases. Here, we provide a detailed review of the mechanisms by which lung cancer-related E3 ligases modify substrate proteins and regulate signaling pathways to facilitate or suppress cancer progression. We hope to show a new perspective on targeted precision therapy for lung cancer.

Role of Nedd4L in Macrophage Pro-Inflammatory Polarization Induced by Influenza A Virus and Lipopolysaccharide Stimulation

Influenza A virus (IAV) infection often leads to influenza-associated fatalities, frequently compounded by subsequent bacterial infections, particularly Gram-negative bacterial co-infections. Lipopolysaccharide (LPS), a primary virulence factor in Gram-negative bacteria, plays a crucial role in influenza-bacterial co-infections. However, the precise pathogenic mechanisms underlying the synergistic effects of viral-bacterial co-infections remain elusive, posing significant challenges for disease management. In our study, we administered a combination of IAV and LPS to mice and examined associated parameters, including the lung function, lung index, wet/dry ratio, serum inflammatory cytokines, Nedd4L expression in lung tissue, and mRNA levels of inflammatory cytokines. Co-infection with IAV and LPS exacerbated lung tissue inflammation and amplified M1 macrophage expression in lung tissue. Additionally, we stimulated macrophages with IAV and LPS in vitro, assessing the inflammatory cytokine content in the cell supernatant and cytokine mRNA expression within the cells. This combined stimulation intensified the inflammatory response in macrophages and upregulated Nedd4L protein and mRNA expression. Subsequently, we used siRNA to knockdown Nedd4L in macrophages, revealing that suppression of Nedd4L expression alleviated the inflammatory response triggered by concurrent IAV and LPS stimulation. Collectively, these results highlight the pivotal role of Nedd4L in mediating the exacerbated inflammatory responses observed in IAV and LPS co-infections.

NEDD4L is a promoter for angiogenesis and cell proliferation in human umbilical vein endothelial cells

Dysregulated angiogenesis leads to neovascularization, which can promote or exacerbate various diseases. Previous studies have proved that NEDD4L plays an important role in hypertension and atherosclerosis. Hence, we hypothesized that NEDD4L may be a critical regulator of endothelial cell (EC) function. This study aimed to define the role of NEDD4L in regulating EC angiogenesis and elucidate their underlying mechanisms. Loss- and gain-of-function of NEDD4L detected the angiogenesis and mobility role in human umbilical vein endothelial cells (HUVECs) using Matrigel tube formation assay, cell proliferation and migration. Pharmacological pathway inhibitors and western blot were used to determine the underlying mechanism of NEDD4L-regulated endothelial functions. Knockdown of NEDD4L suppressed tube formation, cell proliferation and cell migration in HUVECs, whereas NEDD4L overexpression promoted these functions. Moreover, NEDD4L-regulated angiogenesis and cell progression are associated with the phosphorylation of Akt, Erk1/2 and eNOS and the expression of VEGFR2 and cyclin D1 and D3. Mechanically, further evidence was confirmed by using Akt blocker MK-2206, Erk1/2 blocker U0126 and eNOS blocker L-NAME. Overexpression NEDD4L-promoted angiogenesis, cell migration and cell proliferation were restrained by these inhibitors. In addition, overexpression NEDD4L-promoted cell cycle-related proteins cyclin D1 and D3 were also suppressed by Akt blocker MK-2206, Erk1/2 blocker U0126 and eNOS blocker L-NAME. Our results demonstrated a novel finding that NEDD4L promotes angiogenesis and cell progression by regulating the Akt/Erk/eNOS pathways.

NEDD4L in human tumors: regulatory mechanisms and dual effects on anti-tumor and pro-tumor

Tumorigenesis and tumor development are closely related to the abnormal regulation of ubiquitination. Neural precursor cell expressed developmentally downregulated 4-like (NEDD4L), an E3 ubiquitin ligase critical to the ubiquitination process, plays key roles in the regulation of cancer stem cells, as well as tumor cell functions, including cell proliferation, apoptosis, cell cycle regulation, migration, invasion, epithelial-mesenchymal transition (EMT), and tumor drug resistance, by controlling subsequent protein degradation through ubiquitination. NEDD4L primarily functions as a tumor suppressor in several tumors but also plays an oncogenic role in certain tumors. In this review, we comprehensively summarize the relevant signaling pathways of NEDD4L in tumors, the regulatory mechanisms of its upstream regulatory molecules and downstream substrates, and the resulting functional alterations. Overall, therapeutic strategies targeting NEDD4L to treat cancer may be feasible.

YAP Facilitates NEDD4L-Mediated Ubiquitination and Degradation of ACSL4 to Alleviate Ferroptosis in Myocardial Ischemia-Reperfusion Injury

BACKGROUND

Ferroptosis is a novel iron-dependent type of cell death that takes part in the progression of myocardial ischemia/reperfusion injury (MIRI). However, the detailed mechanism of ferroptosis underlying MIRI remains unclear. This study aimed to investigate the regulatory role of yes-associated protein (YAP) in ferroptosis during MIRI.

METHODS

The in vivo and in vitro MIRI models were established in the Sprague-Dawley (SD) rats and H9C2 cardiomyocytes. The infarct volume, pathologic changes, cardiac function, serum levels of lactate dehydrogenase (LDH) and creatine kinase (CK)-MB were detected. Western blotting and immunohistochemistry were performed to measure the expression of YAP, neural precursor cell expressed developmentally downregulated 4-like (NEDD4L) and ferroptosis-related proteins. Ferroptosis was evaluated by Fe2+, malondialdehyde (MDA), LDH, glutathione (GSH), and lipid reactive oxygen species (ROS) levels. Molecular mechanism was analyzed by co-immunoprecipitation (Co-IP), chromatin immunoprecipitation (ChIP), and dual-luciferase reporter assay.

RESULTS

YAP and NEDD4L were remarkably low expressed in MIRI models. YAP overexpression reduced myocardial infarct volume and improved cardiac function. In addition, YAP inhibited MIRI-induced ferroptosis as confirmed by reducing levels of Fe2+, MDA, LDH, lipid ROS, and ferroptosis-related protein ACSL4, and enhancing GSH level and cell viability. Mechanistically, YAP facilitated NEDD4L transcription that consequently caused ubiquitination and degradation of ACSL4, thereby restraining ferroptosis in MIRI. YAP knockdown aggravated MIRI-induced ferroptosis, which was counteracted by NEDD4L overexpression.

CONCLUSIONS

YAP represses MIRI-induced cardiomyocyte ferroptosis via promoting NEDD4L transcription and subsequent ubiquitination and degradation of ACSL4. YAP-mediated ferroptosis inhibition might be a novel therapeutic strategy for MIRI.

The roles of protein ubiquitination in tumorigenesis and targeted drug discovery in lung cancer

The malignant lung cancer has a high morbidity rate and very poor 5-year survival rate. About 80% - 90% of protein degradation in human cells is occurred through the ubiquitination enzyme pathway. Ubiquitin ligase (E3) with high specificity plays a crucial role in the ubiquitination process of the target protein, which usually occurs at a lysine residue in a substrate protein. Different ubiquitination forms have different effects on the target proteins. Multiple short chains of ubiquitination residues modify substrate proteins, which are favorable signals for protein degradation. The dynamic balance adapted to physiological needs between ubiquitination and deubiquitination of intracellular proteins is beneficial to the health of the organism. Ubiquitination of proteins has an impact on many biological pathways, and imbalances in these pathways lead to diseases including lung cancer. Ubiquitination of tumor suppressor protein factors or deubiquitination of tumor carcinogen protein factors often lead to the progression of lung cancer. Ubiquitin proteasome system (UPS) is a treasure house for research and development of new cancer drugs for lung cancer, especially targeting proteasome and E3s. The ubiquitination and degradation of oncogene proteins with precise targeting may provide a bright prospect for drug development in lung cancer; Especially proteolytic targeted chimerism (PROTAC)-induced protein degradation technology will offer a new strategy in the discovery and development of new drugs for lung cancer.

NEDD4 E3 ubiquitin ligases: promising biomarkers and therapeutic targets for cancer

Accumulating evidence has demonstrated that NEDD4 E3 ubiquitin ligase family plays a pivotal oncogenic role in a variety of malignancies via mediating ubiquitin dependent degradation processes. Moreover, aberrant expression of NEDD4 E3 ubiquitin ligases is often indicative of cancer progression and correlated with poor prognosis. In this review, we are going to address association of expression of NEDD4 E3 ubiquitin ligases with cancers, the signaling pathways and the molecular mechanisms by which the NEDD4 E3 ubiquitin ligases regulate oncogenesis and progression, and the therapies targeting the NEDD4 E3 ubiquitin ligases. This review provides the systematic and comprehensive summary of the latest research status of E3 ubiquitin ligases in the NEDD4 subfamily, and proposes that NEDD4 family E3 ubiquitin ligases are promising anti-cancer drug targets, aiming to provide research direction for clinical targeting of NEDD4 E3 ubiquitin ligase therapy.

UBE2T Promotes Temozolomide Resistance of Glioblastoma Through Regulating the Wnt/β-Catenin Signaling Pathway

Purpose

Patients with glioblastoma (GBM) have poor prognosis and limited therapeutic options, largely because of chemoresistance to temozolomide (TMZ) treatment. Ubiquitin conjugating enzyme E2 T (UBE2T) plays a key role in regulating the malignancy of various tumors, including GBM; however, its role in TMZ resistance of GBM has not been elucidated. The purpose of this study was to clarify the role of UBE2T in mediating TMZ resistance and investigate the specific underlying mechanism.

Methods

Western blotting was used to detect the protein levels of UBE2T and Wnt/β-catenin-related factors. CCK-8, flow cytometry, and colony formation assays were used to examine the effect of UBE2T on TMZ resistance. Wnt/β-catenin signaling pathway activation was inhibited using XAV-939, and a xenograft mouse model was generated to clarify the function of TMZ in vivo.

Results

UBE2T knockdown sensitized GBM cells to TMZ treatment, whereas UBE2T overexpression promoted TMZ resistance. The specific UBE2T inhibitor, M435-1279, increased the sensitivity of GBM cells to TMZ. Mechanistically, our results demonstrated that UBE2T induces β-catenin nuclear translocation and increases the protein levels of downstream molecules, including survivin and c-Myc. Inhibition of Wnt/β-catenin signaling using XAV-939 blocked TMZ resistance due to UBE2T overexpression in GBM cells. In addition, UBE2T was shown to facilitate TMZ resistance by inducing Wnt/β-catenin signaling pathway activation in a mouse xenograft model. Combined treatment with TMZ and UBE2T inhibitor achieved superior tumor growth suppression relative to TMZ treatment alone.

Conclusion

Our data reveal a novel role of UBE2T in mediating TMZ resistance of GBM cells via regulating Wnt/β-catenin signaling. These findings indicate that targeting UBE2T has promising potential to overcome TMZ resistance of GBM.

NEDD4L inhibits migration, invasion, cisplatin resistance and promotes apoptosis of bladder cancer cells by inactivating the p62/Keap1/Nrf2 pathway

PURPOSE

This study identified the function of neural precursor cell expressed developmentally down-regulated 4-like (NEDD4L) on bladder cancer (BLCA).

METHODS

NEDD4L expression in BLCA patients was scrutinized. The function of NEDD4L on the viability, apoptosis, migration and invasion of BLCA cells was evaluated by cell counting kit-8, flow cytometry and Transwell assays. The effect of NEDD4L on the cisplatin (DDP) resistance of the DDP-resistant BLCA cells was explored. The influence of NEDD4L on the p62/Keap1/Nrf2 pathway activity in BLCA cells was tested by Western blot. Rescue experiments were implemented to verify whether NEDD4L regulated BLCA cell malignant behavior by mediating the Keap1/Nrf2 pathway activity via p62. The effect of NEDD4L on the growth and the p62/Keap1/Nrf2 pathway activity in vivo was researched in xenograft tumor nude mice models.

RESULTS

The down-regulated NEDD4L in BLCA patients was associated with unfavorable survival. NEDD4L suppressed the viability (inhibition rate 57.1%/49.0%), migration (inhibition rate 49.7%/77.1%), invasion (inhibition rate 50.6%/75.7%), promoted the apoptosis of T24/5637 cells (promotion rate 243.8%/201.9%), reduced IC 50 of DDP-resistant T24/5637 cells from 132.2/101.8 to 57.81/59.71 μM, respectively, and inactivated the p62/Keap1/Nrf2 pathway in T24/5637 cells. p62 up-regulation partially abrogated the inhibition of NEDD4L on the Keap1/Nrf2 pathway activity, the malignant behavior of BLCA cells, and the DDP resistance of DDP-resistant BLCA cells. NEDD4L overexpression inhibited the tumor growth and the p62/Keap1/Nrf2 pathway activity in vivo in BLCA.

CONCLUSION

NEDD4L inhibits the progression of BLCA by inactivating the p62/Keap1/Nrf2 pathway. It may be an effective target for BLCA treatment.

Diverse roles of UBE2T in cancer (Review)

As a leading cause of mortalities worldwide, cancer results from accumulation of both genetic and epigenetic alterations. Disruption of epigenetic regulation in cancer, particularly aberrant ubiquitination, has drawn increasing interest in recent years. The present study aimed to review the roles of ubiquitin‑conjugating enzyme E2 T (UBE2T) and its associated pathways in the pathogenesis of pan‑cancer, and the development of small‑molecule modulators to regulate ubiquitination for treatment strategies. The current study comprehensively investigated the expression landscape and functional significance of UBE2T, as well as its correlation with cancer cell sensitivity to chemotherapy/radiotherapy. Multiple levels of evidence suggested that aberrant UBE2T played important roles in pan‑cancer. Information was collected from 16 clinical trials on ubiquitin enzymes, and it was found that these molecules had an important role in the ubiquitin‑proteasome system. Further studies are necessary to explore their feasibility and effectiveness as diagnostic and prognostic biomarkers, or as up/down‑stream and therapeutic targets for cancer treatment.

Molecular Mechanism of Long Noncoding RNA SNHG14 in Osteogenic Differentiation of Bone Marrow-Derived Mesenchymal Stem Cells through the NEDD4L/FOXA2/PCP4 Axis

Bone marrow-derived mesenchymal stem cells (BMSCs) have a superior potential of osteogenic differentiation (OD) and a promising stem cell type to treat bone defects. This study sought to investigate the molecular mechanism of long noncoding RNA small nucleolar RNA host gene 14 (SNHG14) in OD of BMSCs. Western blot analysis or RT-qPCR showed that SNHG14, neural precursor cell expressed developmentally downregulated 4-like (NEDD4L), and Purkinje cell protein 4 (PCP4) were upregulated whereas forkhead box A2 (FOXA2) was declined in OD of BMSCs. RT-qPCR and cell staining showed that SNHG14 downregulation repressed OD of BMSCs, as manifested by reductions in osteopontin and osteocalcin levels, the mineralization degree, and alkaline phosphatase activity. RNA/Co/chromatin immunoprecipitation and dual-luciferase assays and determination of mRNA stability and ubiquitination level showed that SNHG14 bound to human antigen R improves NEDD4L mRNA stability and expression, further promoted FOXA2 ubiquitination to inhibit FOXA2 expression, and then reduced FOXA2 enrichment on the PCP4 promoter to upregulate PCP4 transcription. Functional rescue experiments showed that the overexpression of NEDD4L or PCP4 and knockdown of FOXA2 both attenuated the inhibition of SNHG14 downregulation on OD of BMSCs. Overall, our findings suggested that SNHG14 promoted OD of BMSCs through the NEDD4L/FOXA2/PCP4 axis.

A network-based dynamic criterion for identifying prediction and early diagnosis biomarkers of complex diseases

Lung adenocarcinoma (LUAD) seriously threatens human health and generally results from dysfunction of relevant module molecules, which dynamically change with time and conditions, rather than that of an individual molecule. In this study, a novel network construction algorithm for identifying early warning network signals (IEWNS) is proposed for improving the performance of LUAD early diagnosis. To this end, we theoretically derived a dynamic criterion, namely, the relationship of variation (RV), to construct dynamic networks. RV infers correlation [Formula: see text] statistics to measure dynamic changes in molecular relationships during the process of disease development. Based on the dynamic networks constructed by IEWNS, network warning signals used to represent the occurrence of LUAD deterioration can be defined without human intervention. IEWNS was employed to perform a comprehensive analysis of gene expression profiles of LUAD from The Cancer Genome Atlas (TCGA) database and the Gene Expression Omnibus (GEO) database. The experimental results suggest that the potential biomarkers selected by IEWNS can facilitate a better understanding of pathogenetic mechanisms and help to achieve effective early diagnosis of LUAD. In conclusion, IEWNS provides novel insight into the initiation and progression of LUAD and helps to define prospective biomarkers for assessing disease deterioration.

Down-regulated NEDD4L facilitates tumor progression through activating Notch signaling in lung adenocarcinoma

Neural precursor cell expressed developmentally down-regulated 4-like protein (NEDD4L), an E3 ubiquitin ligase, exerts an important role in diverse biological processes including development, tumorigenesis, and tumor progression. Although the role of NEDD4L in the pathogenesis of lung adenocarcinoma (LUAD) has been described, the mechanism by which NEDD4L promotes LUAD progression remains poorly understood. In the study, the correlation between NEDD4L level and clinical outcome in LUAD patients was analysed using the data from The Cancer Genome Atlas (TCGA) database. NEDD4L expression in LUAD cell lines and tissue samples was assessed through quantitative real-time PCR (qRT-PCR). The biological function of NEDD4L on regulating LUAD cell proliferation was tested with Cell Counting Kit-8 (CCK-8) assay in vitro, and mouse xenograft tumor model in vivo. We found that NEDD4L expression was significantly decreased in LUAD tissues and cell lines. Lower expression of NEDD4L exhibited a significantly poorer overall survival. Functionally, NEDD4L knockdown in H1299 cells accelerated cell growth, whereas NEDD4L overexpression in A549 cells repressed cell proliferation. NEDD4L overexpression also inhibited tumor xenograft growth in vivo. Mechanistically, NEDD4L decreased the protein stability of notch receptor 2 (Notch2) through facilitating its ubiquitination and degradation by ubiquitin-proteasome system. Consequently, NEDD4L negatively regulated Notch signaling activation in LUAD cells, and RO4929097 (a Notch inhibitor) treatment effectively repressed the effect of NEDD4L knockdown on LUAD cell proliferation. Taken together, these results demonstrate that down-regulated NEDD4L facilitates LUAD progression by activating Notch signaling, and NEDD4L may be a promising target to treat LUAD.