Downregulation of RNF128 Predicts Progression and Poor Prognosis in Patients with Urothelial Carcinoma of the Upper Tract and Urinary Bladder

RNF128 promotes gastric cancer progression by inhibiting autophagy-dependent ferroptosis through Beclin1 ubiquitination

As an important protein post-translational modification process, ubiquitination plays an indispensable role in the regulation of gastric cancer (GC) occurrence and development. And recent studies have demonstrated that this modification is closely related to regulated cell death. This suggests that our therapeutic approach to inhibit the malignant progression of GC by regulating the intracellular death mode through ubiquitination modification becomes possible. Although ubiquitination modification has been well described in some tumorigenesis, its potential role and specific mechanisms are still unknown. In the present study, we identified RNF128, an E3 ubiquitin ligase with a RING structural domain, whose expression was significantly increased in GC. In-depth studies showed that knockdown of RNF128 significantly inhibited GC cell proliferation and increased intracellular autophagic flux and lipid peroxidation production, and we hypothesized that autophagy-dependent ferroptosis might be the main mode of death mediated by RNF128. Mechanistically, RNF128 directly binds and ubiquitinates degradation of Beclin1 through its PA structural domain and significantly inhibits the Beclin1/solute transport family 7 member 11(SLC7A11)/glutathione peroxidase 4(GPX4) axis. Taken together, our study reports for the first time that RNF128 acts as a tumor promoter to inhibit autophagy-dependent ferroptosis in GCs by targeting Beclin1. These data provide new insights into the activation of intracellular ferroptosis to inhibit malignant tumor progression and are expected to provide a new strategy for molecular therapy in clinical GC patients.

RNF19A inhibits bladder cancer progression by regulating ILK ubiquitination and inactivating the AKT/mTOR signalling pathway

BACKGROUND

The role of the RING finger protein superfamily in carcinogenesis has been widely studied, but one member of this family, RNF19A, has not yet been thoroughly explored in bladder cancer (BCa).

METHODS

The expression levels of RNF19A in BCa samples and cell lines were analysed through data mining of public resources and further experiments. BCa cells in which RNF19A was stably overexpressed or knocked down were generated through lentivirus infection. The effects of RNF19A on cell proliferation, migration, and invasion were explored by performing a series of in vitro experiments, including CCK-8, colony formation, wound healing, and Transwell invasion assays. Using bioinformatics methods and multiple experiments, including western blot, qRT‒PCR, immunoprecipitation, cycloheximide, ubiquitination, and rescue assays, the mechanism underlying the effect of RNF19A on the progression of BCa was investigated.

RESULTS

Here, we found that RNF19A expression was reduced in BCa samples and cell lines and that lower RNF19A expression predicted shorter overall survival of BCa patients. Functionally, forced expression of RNF19A suppressed BCa cell proliferation, migration, and invasion by inactivating the AKT/mTOR signalling pathway, whereas silencing RNF19A had the opposite effects. Mechanistically, RNF19A could directly interact with ILK and promote its ubiquitination and degradation. Rescue experiments revealed that forced ILK expression partially rescued the decreased phosphorylation of AKT, mTOR, and S6K1 caused by RNF19A overexpression and that the increased levels of the p-AKT, p-mTOR, and p-S6K1 proteins induced by RNF19A knockdown were eliminated after silencing ILK. Similarly, the effects of RNF19A overexpression or knockdown on the phenotypes of cell proliferation, migration, and invasion could also be restored by forced or decreased ILK expression.

CONCLUSIONS

RNF19A suppressed the proliferation, migration, and invasion abilities of BCa cells by regulating ILK ubiquitination and inactivating the AKT/mTOR signalling pathway. RNF19A might be a potential prognostic biomarker and promising therapeutic target for BCa.

Downregulation of RNF128 Inhibits the Proliferation, Migration, Invasion and EMT of Colorectal Cancer Cells

Colorectal cancer has the third highest incidence and second highest mortality rate among all cancer types. Exploring the molecular mechanisms driving malignant proliferation and metastasis of colorectal cancer will benefit the treatment and management of cancer patients. Recent studies have reported diametrically opposed roles of Ring finger protein 128 (RNF128) in different types of cancer. However, the role of RNF128 in colorectal cancer is still completely unknown, which this study attempts to analyze. The differential expression of RNF128 mRNA and protein in 30 pairs of colorectal cancer and corresponding peritumoral tissues was detected using RT-qPCR, western blot and immunohistochemical staining. siRNA specifically targeting RNF128 was transfected into colorectal cancer cell lines (SW1116 and SW480) cultured in vitro. Proliferation, growth, migration, invasion and epithelial-mesenchymal transition (EMT) of colorectal cancer cells were examined by CCK-8, clone formation, wound-healing, transwell, western blot and immunofluorescence assays. Both RNF128 mRNA and protein levels were significantly increased in colorectal cancer tissues compared to pericarcinoma tissues. Knockdown of RNF128 significantly inhibited the proliferation, growth, migration, invasion and EMT of SW480 and SW1116 cells. Targeting RNF128 may benefit the treatment and management of colorectal cancer.

E3 ubiquitin ligase RNF128 attenuates colitis and colorectal tumorigenesis by triggering the degradation of IL-6 receptors

INTRODUCTION

Intestinal immune dysregulation is strongly linked to the occurrence and formation of tumors. RING finger protein 128 (RNF128) has been identified to play distinct immunoregulatory functions in innate and adaptive systems. However, the physiological roles of RNF128 in intestinal inflammatory conditions such as colitis and colorectal cancer (CRC) remain controversial.

OBJECTIVES

To elucidate the function and mechanism of RNF128 in colitis and CRC.

METHODS

Animal models of dextran sodium sulfate (DSS)-induced colitis and azoxymethane (AOM)/DSS-induced CRC were established in WT and Rnf128-deficient mice and evaluated by histopathology. Co-immunoprecipitation and ubiquitination analyses were employed to investigate the role of RNF128 in IL-6-STAT3 signaling.

RESULTS

RNF128 was significantly downregulated in clinical CRC tissues compared with paired peritumoral tissues. Rnf128-deficient mice were hypersusceptible to both colitis induced by DSS and CRC induced by AOM/DSS or APC mutation. Loss of RNF128 promoted the proliferation of CRC cells and STAT3 activation during the early transformative stage of carcinogenesis in vivo and in vitro when stimulated by IL-6. Mechanistically, RNF128 interacted with the IL-6 receptor α subunit (IL-6Rα) and membrane glycoprotein gp130 and mediated their lysosomal degradation in ligase activity-dependent manner. Through a series of point mutations in the IL-6 receptor, we identified that RNF128 promoted K48-linked polyubiquitination of IL-6Rα at K398/K401 and gp130 at K718/K816/K866. Additionally, blocking STAT3 activation effectively eradicated the inflammatory damage of Rnf128-deficient mice during the transformative stage of carcinogenesis.

CONCLUSION

RNF128 attenuates colitis and colorectal tumorigenesis by inhibiting IL-6-STAT3 signaling, which sheds novel insights into the modulation of IL-6 receptors and the inflammation-to-cancer transition.

Lymph Node Dissection in Upper Tract Urothelial Carcinoma: Current Status and Future Perspectives

PURPOSE OF REVIEW

This narrative review aims to evaluate the role of lymph node dissection (LND) in upper tract urothelial carcinoma (UTUC) and its implications for staging and management outcomes, as well as future perspectives.

RECENT FINDINGS

Multiple studies have demonstrated the limitations of conventional imaging techniques in accurately localizing lymph node metastasis (LNM) in UTUC. While 18F-fluorodeoxyglucose positron emission tomography with computed tomography (18FDG-PET/CT) shows promise for preoperative LNM detection, its specificity is low. Alternative methods such as choline PET/CT and sentinel lymph node detection are under consideration but require further investigation. Additionally, various preoperative factors associated with LNM hold potential for predicting nodal involvement, thereby improving nodal staging and oncologic outcomes of LND. Several surgical approaches, including segmental ureterectomy and robot-assisted nephroureterectomy, provide a possibility for LND, while minimizing morbidity. LND remains the primary nodal staging tool for UTUC, but its therapeutic benefit is still uncertain. Advances in imaging techniques and preoperative risk assessment show promise in improving LNM detection. Further research and multi-center studies are needed to comprehensively assess the advantages and limitations of LND in UTUC, as well as the long-term outcomes of alternative staging and treatment strategies.

RNF128 expression in lung adenocarcinoma is a favorable prognostic factor associated with decreased tumor-associated macrophages

OBJECTIVES

Molecular-level research has linked RING finger (RNF) protein family members to carcinogenesis and tumor progression. Among them, RNF128 is related to tumor progression, but reports on its association with lung cancer are few. This study aimed to clarify the unknown association between RNF128 expression and clinical outcomes in patients with lung adenocarcinoma.

METHODS

Clinical data of 545 patients with therapy-naïve lung adenocarcinoma who underwent lobectomy with systematic lymph node dissection between 1999 and 2016 were retrospectively reviewed. Histological and immunohistochemical analyses were conducted to evaluate the relationship between RNF128 expression and prognosis.

RESULTS

Among adenocarcinoma histologic types, acinar, micropapillary, and solid tumors did not express RNF128 compared with other histologic types (p < 0.001). Patients with high RNF128 expression exhibited fewer clusters of differentiated (CD) 68+ tumor-associated macrophages (TAMs) and CD163+ TAMs. Multivariate analysis of relapse-free survival (RFS) and overall survival (OS) revealed that the lack of RNF128 expression was an independent prognostic factor for poor RFS (hazard ratio [HR] 1.60, p = 0.029) and OS (HR 1.83, p = 0.041), suggesting that RNF128 expression is a favorable prognostic factor.

CONCLUSION

RNF128 expression may be an independent predictor of favorable outcomes in Japanese patients with untreated lung adenocarcinoma who undergo surgical resection. Further elucidation of the role of TAM-related E3 ubiquitin ligase in immune function may facilitate the development of effective immunomodulatory therapies for lung adenocarcinoma.

Ring finger protein 128 promotes, rather than inhibits, colorectal cancer progression by regulating the Hippo signaling pathway

Background

Colorectal cancer is a common malignancy of the gastrointestinal tract, and its incidence and mortality rates have increased in recent years. RNF128 is an E3 ubiquitin ligase that plays an important role as a suppressor gene or oncogene in various cancers, but its mechanism in colorectal cancer is not yet clear. The aim of this study was to investigate the role and mechanism of RNF128 in colorectal cancer.

Methods

The expression of RNF128 in colorectal cancer tissues was assessed by immunohistochemistry and western blotting. The proliferation ability of colorectal cancer cells was measured by colony formation assay and CCK-8 assay, the migration and invasion ability of colorectal cancer cells was measured by wound healing assay and transwell assay, and the protein expression levels of the Hippo signaling pathway and its target gene were examined by western blotting. Immunoprecipitation was used to assess the interaction of RNF128 with MST. In vivo, a xenograft tumor model was used to detect the effect of RNF128 on tumor growth.

Results

At the tissue level, the expression level of RNF128 was significantly higher in colorectal cancer tissues than in adjacent normal tissues. In LoVo cells and HCT116 cells, the proliferation, migration and invasion abilities were significantly reduced with RNF128 knockdown. At the protein level, knockdown of RNF128 resulted in significant activation of the Hippo signaling pathway. In vivo experiments, the volume and weight of xenograft tumors in nude mice were significantly decreased compared with those in the normal control group with RNF128 knockdown.

Conclusion

RNF128 promotes the malignant behaviors of colorectal cancer cells by inhibiting the Hippo signaling pathway, which may provide a new target for colorectal cancer prevention and treatment.

RING finger protein 128 (RNF128) regulates malignant biological behaviors of colorectal cancer cells via PI3K/AKT signaling pathway

This study was designed and conducted to clarify the impact of RNF128 expression on malignant biological behaviors of colorectal cancer (CRC) cells and the underlying mechanism. The expression of RNF128 in CRC tissues was analyzed using mRNA sequencing data of TCGA database and was validated by Western blot assay. The experimental studies on biological functions of RNF128 in vitro were conducted to assess its impact on the proliferation, apoptosis, and metastasis of CRC cells. Furthermore, tumor xenograft models in nude mice were established to investigate the relationship between RNF128 expression and tumor growth in vivo. The expression levels of both RNF128 mRNA and protein were significantly increased in CRC tissues (p < .001). The knockdown of RNF128 markedly suppressed the malignant phenotype of HCT116 and SW480 cells in vitro, including cell growth, antiapoptosis, migration, and invasion (p < .001). On the other hand, knockdown of RNF128 exerted a remarkable effect on the growth inhibition of tumor xenografts in vivo (p < .001). Further investigation revealed that RNF128 knockdown lead to a significant decrease in the expression of p-AKT and p-PI3K protein. More importantly, the proliferative, antiapoptotic, metastatic abilities of RNF128-knockdown cells were markedly increased by 740 Y-P treatment (p < .001). These findings further suggested that PI3K/AKT signaling pathway played a key role in RNF128-mediated aggressive phenotype of CRC cells. RNF128 functions as a tumor promoter in the pathogenesis of CRC via regulating PI3K/AKT pathway, and it could be a valuable target for CRC treatment.

The roles of E3 ligases in Hepatocellular carcinoma

Hepatocarcinogenesis is a complex multistep biological process involving genetic and epigenetic alterations that are accompanied by activation of oncoproteins and inactivation of tumor suppressors, which in turn results in Hepatocellular carcinoma (HCC), one of the common tumors with high morbidity and mortality worldwide. The ubiquitin-proteasome system (UPS) is the key to protein degradation and regulation of physiological and pathological processes, and E3 ligases are key enzymes in the UPS that contain a variety of subfamily proteins involved in the regulation of some common signal pathways in HCC. There is growing evidence that many structural or functional dysfunctions of E3 are engaged in the development and progression of HCC. Herein, we review recent research advances in HCC-associated E3 ligases, describe their structure, classification, functional roles, and discuss some mechanisms of the abnormal activation or inactivation of the HCC-associated signal pathway due to the binding of E3 to known substrates. In addition, given the success of proteasome inhibitors in the treatment of malignant cancers, we characterize the current knowledge and future prospects for targeted therapies against aberrant E3 in HCC.

RNF128 suppresses the malignancy of colorectal cancer cells via inhibition of Wnt/β-catenin signaling

PURPOSE

Colorectal cancer (CRC) is one of the most frequent tumors and causes of mortality worldwide. Ubiquitin ligase was reported to regulate multiple cellular processes, including tumorigenesis. As ubiquitin E3 ligases, RING-finger proteins play a key role in physiological and pathophysiological processes.

METHODS

We compared the expression levels of RNF128 in CRC tissues by western-blotting and qRT-PCR. Knockdown and overexpression of RNF128 were performed to examine its effect on proliferation and metastasis of CRC cells. Using western blot and co-immunoprecipitation assays, we explored the possible mechanisms underlying the effect of RNF128 in CRC cells.

RESULTS

We found that the expression level of RNF128 was correlated with the CRC tumorigenicity. Overexpression or knockdown of RNF128 suppressed or elevated CRC cell proliferation, migration and invasion, respectively. We further determined that RNF128 regulated β-catenin ubiquitination and thus inhibited Wnt/β-catenin signaling in CRC cells.

CONCLUSION

Our research demonstrated that RNF128 inhibited cell proliferation and metastasis of CRC cells via Wnt/β-catenin signaling-mediated deubiquitination.

Novel deep learning-based survival prediction for oral cancer by analyzing tumor-infiltrating lymphocyte profiles through CIBERSORT

The tumor microenvironment (TME) within mucosal neoplastic tissue in oral cancer (ORCA) is greatly influenced by tumor-infiltrating lymphocytes (TILs). Here, a clustering method was performed using CIBERSORT profiles of ORCA data that were filtered from the publicly accessible data of patients with head and neck cancer in The Cancer Genome Atlas (TCGA) using hierarchical clustering where patients were regrouped into binary risk groups based on the clustering-measuring scores and survival patterns associated with individual groups. Based on this analysis, clinically reasonable differences were identified in 16 out of 22 TIL fractions between groups. A deep neural network classifier was trained using the TIL fraction patterns. This internally validated classifier was used on another individual ORCA dataset from the International Cancer Genome Consortium data portal, and patient survival patterns were precisely predicted. Seven common differentially expressed genes between the two risk groups were obtained. This new approach confirms the importance of TILs in the TME and provides a direction for the use of a novel deep-learning approach for cancer prognosis.

Regulation of p53 by E3s

More than 40 years of research on p53 have given us tremendous knowledge about this protein. Today we know that p53 plays a role in different biological processes such as proliferation, invasion, pluripotency, metabolism, cell cycle control, ROS (reactive oxygen species) production, apoptosis, inflammation and autophagy. In the nucleus, p53 functions as a bona-fide transcription factor which activates and represses transcription of a number of target genes. In the cytoplasm, p53 can interact with proteins of the apoptotic machinery and by this also induces cell death. Despite being so important for the fate of the cell, expression levels of p53 are kept low in unstressed cells and the protein is largely inactive. The reason for the low expression level is that p53 is efficiently degraded by the ubiquitin-proteasome system and the vast inactivity of the tumor suppressor protein under normal growth conditions is due to the absence of activating and the presence of inactivating posttranslational modifications. E3s are important enzymes for these processes as they decorate p53 with ubiquitin and small ubiquitin-like proteins and by this control p53 degradation, stability and its subcellular localization. In this review, we provide an overview about E3s that target p53 and discuss the connection between p53, E3s and tumorigenesis.

Use of signals of positive and negative selection to distinguish cancer genes and passenger genes

A major goal of cancer genomics is to identify all genes that play critical roles in carcinogenesis. Most approaches focused on genes positively selected for mutations that drive carcinogenesis and neglected the role of negative selection. Some studies have actually concluded that negative selection has no role in cancer evolution. We have re-examined the role of negative selection in tumor evolution through the analysis of the patterns of somatic mutations affecting the coding sequences of human genes. Our analyses have confirmed that tumor suppressor genes are positively selected for inactivating mutations, oncogenes, however, were found to display signals of both negative selection for inactivating mutations and positive selection for activating mutations. Significantly, we have identified numerous human genes that show signs of strong negative selection during tumor evolution, suggesting that their functional integrity is essential for the growth and survival of tumor cells.

RNF128 Promotes Malignant Behaviors via EGFR/MEK/ERK Pathway in Hepatocellular Carcinoma

BACKGROUND

The ubiquitin-proteasome system participates in the pathogenesis and progression of hepatocellular carcinoma (HCC). As an E3 ubiquitin ligase, RNF128 has been proved vital in carcinogenesis, whereas, little is known about the oncogenic mechanisms of RNF128 in HCC.

MATERIALS AND METHODS

Through tissue microarray from HCC patients, we analyzed RNF128 expression and its relationship with clinical outcomes in HCC. Western blot and quantitative realtime polymerase chain reaction (qRT-PCR) were performed to examine expression levels of RNF128 in HCC tissues and cell lines. Effects of RNF128 on HCC cellular biological functions and the potential mechanism were evaluated through knockdown and overexpression assays in vitro and in vivo methods.

RESULTS

RNF128 expression was found to be remarkably elevated in HCC tissues compared with adjacent normal tissues. Furthermore, the overexpression of RNF128 enhanced hepatoma cells proliferation, colony formation, migration, invasion, and apoptotic resistance both in vitro and in vivo. Mechanistically, RNF128 activated EGFR/MEK/ERK signaling pathway and the EGFR inhibitor, gefitinib partially reversed RNF128-enhanced proliferation, invasion, and migration in hepatoma cells.

CONCLUSION

RNF128 promotes HCC progression by activating EGFR/MEK/ERK signaling pathway, which might function as a novel prognostic molecular signature with the potential to be a candidate therapeutic target for HCC patients.

Downregulation of RNF128 activates Wnt/β-catenin signaling to induce cellular EMT and stemness via CD44 and CTTN ubiquitination in melanoma

BACKGROUND

Ring finger proteins (RNFs) were involved in carcinogenesis. Here, we aimed to explore the detailed mechanism of RNF128 in the progression of melanoma.

METHODS

We reanalyzed several gene expression profiles from the Gene Expression Omnibus (GEO) database and obtained the overlapped differential expressed RNF genes. Among them, RNF128 was selected to further explore its expression, the biological significance, and the underlying molecular mechanism, as well as the clinical relevance in melanoma patients.

RESULTS

RNF128 was found to be significantly downregulated in the selected datasets, which was further verified in our melanoma tissues. Moreover, RNF128 downregulation was shown to correlate with the malignant phenotype of melanoma, and further functional assays demonstrated that low levels of RNF128 promoted melanoma progression via inducing cell epithelial-mesenchymal transition (EMT) and the acquisition of stemness. Mechanistically, RNF128 interference activated the Wnt pathway via simultaneously ubiquitinating CD44/cortactin (CTTN), resulting in CD44 and c-Myc transcription, thus revealed that RNF128 participated in a positive feedback of the Wnt pathway-CD44 loop. Clinically, we found that patients expressing low RNF128 and high CD44/CTTN levels had a poor prognosis.

CONCLUSION

Downregulated RNF128 activates Wnt signaling to induce cellular EMT and stemness by ubiquitinating and degrading CD44/CTTN, and RNF128 is a reliable diagnostic and prognostic biomarker, and a deeper understanding of RNF128 may contribute to the treatment of melanoma.