The concomitant use of USP28 and p53 to predict the progression of urothelial carcinoma of the bladder

Roles of deubiquitinases in urologic cancers (Review)

Human health is endangered by the occurrence and progression of urological cancers, including renal cell carcinoma, prostate cancer and bladder cancer, which are usually associated with the activation of oncogenic factors and inhibition of cancer suppressors. The primary mechanism for protein breakdown in cells is the ubiquitin-proteasome system, whilst deubiquitinases contribute to the reversal of this process. However, both are important for protein homeostasis. Deubiquitination may also be involved in the control of the cell cycle, proliferation and apoptosis, and dysregulated deubiquitination is associated with the malignant transformation, invasion and metastasis of urologic malignancies. Therefore, a comprehensive summary of the mechanisms underlying deubiquitination in urological cancers may provide novel strategies and insights for diagnosis and treatment. The present review aimed to methodically clarify the role of deubiquitinating enzymes in urinary system cancers as well as their prospective application prospects for clinical treatment.

Deubiquitinating enzyme USP28 inhibitor AZ1 alone and in combination with cisplatin for the treatment of non-small cell lung cancer

Lung cancer is one of the most common malignant tumors. Despite decades of research, the treatment of lung cancer remains challenging. Non-small cell lung cancer (NSCLC) is the primary type of lung cancer and is a significant focus of research in lung cancer treatment. The deubiquitinase ubiquitin-specific protease 28 (USP28) plays a role in the progression of various tumors and serves as a potential therapeutic target. This study aims to determine the role of USP28 in the progression of NSCLC. We examined the impact of the USP28 inhibitor AZ1 on the cell cycle, apoptosis, DNA damage response, and cellular immunogenicity in non-small cell lung cancer. We observed that AZ1 and siUSP28 induce DNA damage, leading to the activation of Noxa-mediated mitochondrial apoptosis. The dsDNA and mtDNA released from DNA damage and mitochondrial apoptosis activate tumor cell immunogenicity through the cGAS-STING signaling pathway. Simultaneously, targeting USP28 promotes the degradation of c-MYC, resulting in cell cycle arrest and inhibition of DNA repair. This further promotes DNA damage-induced cell apoptosis mediated by the Noxa protein, thereby enhancing tumor cell immunogenicity mediated by dsDNA and mtDNA. Moreover, we found that the combination of AZ1 and cisplatin (DDP) can enhance therapeutic efficacy, thereby providing a new strategy to overcome cisplatin resistance in NSCLC. These findings suggest that targeting USP28 and combining it with cisplatin are feasible strategies for treating NSCLC.

Recent advances in the development of deubiquitinases inhibitors as antitumor agents

Ubiquitination is a type of post-translational modification that covalently links ubiquitin to a target protein, which plays a critical role in modulating protein activity, stability, and localization. In contrast, this process is reversed by deubiquitinases (DUBs), which remove ubiquitin from ubiquitinated substrates. Dysregulation of DUBs is associated with several human diseases, such as cancer, inflammation, neurodegenerative disorders, and autoimmune diseases. Thus, DUBs have become promising targets for drug development. Although the physiological and pathological effects of DUBs are increasingly well understood, the clinical drug discovery of selective DUB inhibitors has been challenging. Herein, we summarize the structures and functions of main classes of DUBs and discuss the recent progress in developing selective small-molecule DUB inhibitors as antitumor agents.

Comprehensive prognostic and immunological analysis of Ubiquitin Specific Peptidase 28 in pan-cancers and identification of its role in hepatocellular carcinoma cell lines

BACKGROUND

Ubiquitin Specific Peptidase 28 (USP28), as a member of the DUBs family, has been reported to regulate the occurrence and development of some tumors, but its oncogenic role in tumor immunity is still unknown.

METHODS

The comprehensive view of USP28 expression in tumor and normal samples was obtained from public databases, including The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), and Cancer Cell Line Encyclopedia (CCLE). We analyzed the genomic alterations of USP28 in various cancers using the cBioPortal dataset. Besides, gene set enrichment analysis was used to analyze the associated cancer hallmarks with USP28 expression, and TIMER2.0 was taken to investigate the immune cell infiltrations related to the USP28 level.

RESULTS

USP28 is highly expressed in most tumors and has prognostic value across various cancer types. Moreover, a significant correlation exists between USP28 and immune regulators, clinical staging, checkpoint inhibitor response, MSI, TMB, CNV, MMR defects, and DNA methylation. Additionally, USP28 expression is strongly associated with the infiltration levels of neutrophils and NK cells in most tumor types. One of the most significant findings of our study was that USP28 could serve as a significant predictor of anti-CTLA4 therapy response in melanoma patients. Additionally, our molecular biology experiments validated that the knockdown of USP28 substantially reduced the proliferative and invasive abilities of the HCC cell lines.

CONCLUSIONS

Our study suggests that USP28 could potentially serve as a biomarker for cancer immunologic infiltration and poor prognosis, with potential applications in developing novel cancer treatment strategies.

Ubiquitin-specific protease 28: the decipherment of its dual roles in cancer development

As significant posttranslational modifications, ubiquitination and deubiquitination, whose balance is modulated by ubiquitin-conjugating enzymes and deubiquitinating enzymes (DUBs), can regulate many biological processes, such as controlling cell cycle progression, signal transduction and transcriptional regulation. Belonging to DUBs, ubiquitin-specific protease 28 (USP28) plays an essential role in turning over ubiquitination and then contributing to the stabilization of quantities of substrates, including several cancer-related proteins. In previous studies, USP28 has been demonstrated to participate in the progression of various cancers. Nevertheless, several reports have recently shown that in addition to promoting cancers, USP28 can also play an oncostatic role in some cancers. In this review, we summarize the correlation between USP28 and tumor behaviors. We initially give a brief introduction of the structure and related biological functions of USP28, and we then introduce some concrete substrates of USP28 and the underlying molecular mechanisms. In addition, the regulation of the actions and expression of USP28 is also discussed. Moreover, we concentrate on the impacts of USP28 on diverse hallmarks of cancer and discuss whether USP28 can accelerate or inhibit tumor progression. Furthermore, clinical relevance, including impacting clinical prognosis, influencing therapy resistance and being the therapy target in some cancers, is depicted systematically. Thus, assistance may be given to future experimental designs by the information provided here, and the potential of targeting USP28 for cancer therapy is emphasized.

Long Non-coding RNA LINC01426 Contributes to the Malignant Behaviors of NSCLC Via Acting As a Sponge for miR-143-3p

Recently, long non-coding RNA (lncRNA) is proved to play critical roles in non-small cell lung cancer (NSCLC) progression. However, the detailed effects of LINC01426 in NSCLC and its functional mechanism remain unknown. The expression of LINC01426, microRNA-143-3p (miR-143-3p), and Ubiquitin-specific peptidase 28 (USP28) was assessed by quantitative real-time polymerase chain reaction (RT-qPCR). The colony-forming ability was determined by colony-forming assay. 5-ethynyl-2'-deoxyuridine (EdU) staining assay was performed to evaluate cell proliferation. The migrated and invaded abilities of cells were measured by transwell assays. Flow cytometry was used to examine cell apoptosis. The protein expression was analyzed by Western blot analysis. The glycolysis ability was analyzed by commercial kits. Dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay, and RNA pull-down assay were used to confirm relationship among LINC01426, miR-143-3p, and USP28. A xenograft experiment was conducted to explore the effects of LINC01426 inhibition in vivo. Our results confirmed that LINC01426 and USP28 expression were increased, while miR-143-3p expression was decreased in NSCLC tissues and cells. Further functional experiments demonstrated that LINC01426 inhibition markedly impaired cell proliferation, migration, invasion, autophagy, and glycolysis while induced apoptosis in NSCLC cells, and LINC01426 derived malignant behaviors of NSCLC cells by sponging miR-143-3p. Additionally, LINC01426 regulated USP28 expression by sponging miR-143-3p. USP28 overexpression partly overturned the inhibitory effect of miR-143-3p on NSCLC progression. Consistently, silencing of LINC01426 significantly inhibited the growth of NSCLC tumor in vivo. LINC01426 accelerated the malignant progression of NSCLC. Mechanistically, LINC01426 acted as a competing endogenous RNA (ceRNA) for miR-143-3p to upregulate USP28 expression.

USP28 facilitates pancreatic cancer progression through activation of Wnt/β-catenin pathway via stabilising FOXM1

Ubiquitination is an important post-translational modification that can be reversed by a family of enzymes called deubiquitinating enzymes (DUBs). Ubiquitin-specific protease 28 (USP28), a member of the DUBs family, functions as a potential tumour promoter in various cancers. However, the biological function and clinical significance of USP28 in pancreatic cancer (PC) are still unclear. Here, we showed that PC tumours had higher USP28 expression compared with that of normal pancreatic tissues, and high USP28 level was significantly correlated with malignant phenotype and shorter survival in patients with PC. Overexpression of USP28 accelerated PC cell growth, whereas USP28 knockdown impaired PC cell growth both in vitro and in vivo. Further, we found that USP28 promoted PC cell growth by facilitating cell cycle progression and inhibiting apoptosis. Mechanistically, USP28 deubiquitinated and stabilised FOXM1, a critical mediator of Wnt/β-catenin signalling. USP28-mediated stabilisation of FOXM1 significantly promoted nucleus β-catenin trans-activation, which in turn led to the activation of the Wnt/β-catenin pathway. Finally, restoration of FOXM1 expression abolished the anti-tumour effects of USP28-silencing. Thus, USP28 contributes to PC pathogenesis through enhancing the FOXM1-mediated Wnt/β-catenin signalling, and could be a potential diagnostic and therapeutic target for PC cases.