The role of ubiquitin-specific peptidases in cancer progression

OTUB2 silencing promotes ovarian cancer via mitochondrial metabolic reprogramming and can be synthetically targeted by CA9 inhibition

Ovarian cancer is an aggressive gynecological tumor characterized by a high relapse rate and chemoresistance. Ovarian cancer exhibits the cancer hallmark of elevated glycolysis, yet effective strategies targeting cancer cell metabolic reprogramming to overcome therapeutic resistance in ovarian cancer remain elusive. Here, we revealed that epigenetic silencing of Otubain 2 (OTUB2) is a driving force for mitochondrial metabolic reprogramming in ovarian cancer, which promotes tumorigenesis and chemoresistance. Mechanistically, OTUB2 silencing destabilizes sorting nexin 29 pseudogene 2 (SNX29P2), which subsequently prevents hypoxia-inducible factor-1 alpha (HIF-1α) from von Hippel-Lindau tumor suppressor-mediated degradation. Elevated HIF-1α activates the transcription of carbonic anhydrase 9 (CA9) and drives ovarian cancer progression and chemoresistance by promoting glycolysis. Importantly, pharmacological inhibition of CA9 substantially suppressed tumor growth and synergized with carboplatin in the treatment of OTUB2-silenced ovarian cancer. Thus, our study highlights the pivotal role of OTUB2/SNX29P2 in suppressing ovarian cancer development and proposes that targeting CA9-mediated glycolysis is an encouraging strategy for the treatment of ovarian cancer.

USP24-i-101 targeting of USP24 activates autophagy to inhibit drug resistance acquired during cancer therapy

Drug resistance in cancer therapy is the major reason for poor prognosis. Addressing this clinically unmet issue is important and urgent. In this study, we found that targeting USP24 by the specific USP24 inhibitors, USP24-i and its analogues, dramatically activated autophagy in the interphase and mitotic periods of lung cancer cells by inhibiting E2F4 and TRAF6, respectively. USP24 functional knockout, USP24C1695A, or targeting USP24 by USP24-i-101 inhibited drug resistance and activated autophagy in gefitinib-induced drug-resistant mice with doxycycline-induced EGFRL858R lung cancer, but this effect was abolished after inhibition of autophagy, indicating that targeting USP24-mediated induction of autophagy is required for inhibition of drug resistance. Genomic instability and PD-L1 levels were increased in drug resistant lung cancer cells and were inhibited by USP24-i-101 treatment or knockdown of USP24. In addition, inhibition of autophagy by bafilomycin-A1 significantly abolished the effect of USP24-i-101 on maintaining genomic integrity, decreasing PD-L1 and inhibiting drug resistance acquired in chemotherapy or targeted therapy. In summary, an increase in the expression of USP24 in cancer cells is beneficial for the induction of drug resistance and targeting USP24 by USP24-i-101 optimized from USP24-i inhibits drug resistance acquired during cancer therapy by increasing PD-L1 protein degradation and genomic stability in an autophagy induction-dependent manner.

K48-linked deubiquitination of VGLL4 by USP15 enhances the efficacy of tumor immunotherapy in triple-negative breast cancer

Immunotherapy based on PD-1/PD-L1 antagonists has been demonstrated to be efficacious in inducing tumor remission in patients with triple-negative breast cancer (TNBC). However, tumor immune evasion caused by the PD-1/PD-L1 pathway inhibits the immunotherapeutic effect of PD-1/PD-L1 inhibitors against TNBC. Therefore, identifying potential targets for blocking the PD-1/PD-L1 pathway is a compelling strategy for TNBC treatment. Here, we discovered that VGLL4 could inhibit PD-L1 transcription by suppressing STAT3 activation, thereby enhancing the efficacy of anti-PD-1 antibody immunotherapy in TNBC. Low expression of USP15, a deubiquitinating enzyme of VGLL4, was associated with reduced CD8+ T cell infiltration and poor prognosis in TNBC patients. USP15 was found to inhibit PD-L1 transcription, leading to increased CD8+ T cell infiltration and thus enhancing the efficacy of TNBC immunotherapy. Furthermore, SART3 regulated VGLL4 stability and PD-L1 transcription by influencing the nuclear translocation of USP15. In conclusion, our study provides new insights into the biological regulation of PD-L1, identifies a previously unrecognized regulator of this critical immune checkpoint, and highlights potential therapeutic targets for overcoming immune evasion in TNBC.

The mechanism of USP43 in the development of tumor: a literature review

Ubiquitination of the proteins is crucial for governing protein degradation and regulating fundamental cellular processes. Deubiquitinases (DUBs) have emerged as significant regulators of multiple pathways associated with cancer and other diseases, owing to their capacity to remove ubiquitin from target substrates and modulate signaling. Consequently, they represent potential therapeutic targets for cancer and other life-threatening conditions. USP43 belongs to the DUBs family involved in cancer development and progression. This review aims to provide a comprehensive overview of the existing scientific evidence implicating USP43 in cancer development. Additionally, it will investigate potential small-molecule inhibitors that target DUBs that may have the capability to function as anti-cancer medicines.

The role of deubiquitinases in cardiac disease

Deubiquitinases are a group of proteins that identify and digest monoubiquitin chains or polyubiquitin chains attached to substrate proteins, preventing the substrate protein from being degraded by the ubiquitin-proteasome system. Deubiquitinases regulate cellular autophagy, metabolism and oxidative stress by acting on different substrate proteins. Recent studies have revealed that deubiquitinases act as a critical regulator in various cardiac diseases, and control the onset and progression of cardiac disease through a board range of mechanism. This review summarizes the function of different deubiquitinases in cardiac disease, including cardiac hypertrophy, myocardial infarction and diabetes mellitus-related cardiac disease. Besides, this review briefly recapitulates the role of deubiquitinases modulators in cardiac disease, providing the potential therapeutic targets in the future.

Cinobufotalin regulates the USP36/c-Myc axis to suppress malignant phenotypes of colon cancer cells in vitro and in vivo

Ubiquitin-specific protease 36 (USP36) has been reported to exhibit oncogenic effects in various malignancies, but the function of USP36 in colon cancer progression remains indefinite. Herein, we aimed to determine the role and mechanism of USP36 in malignant phenotypes of colon cancer cells and explore the potential drug targeting USP36. Bioinformatics analyses indicated that USP36 is highly expressed and significantly related to tumor stages in colon cancer. Besides, USP36 was further up-regulated in oxaliplatin (Oxa)-resistant colon cancer cells. Colony formation, Edu staining, Transwell, wound healing, sphere formation, and CCK-8 assays were conducted and showed that the proliferation, Oxa-resistance, migration, stemness, and invasion of HCT116 cells were promoted after overexpressing USP36, while suppressed by USP36 knockdown. Mechanically, USP36 enhances c-Myc protein stabilization in HCT116 cells via deubiquitination. AutoDock tool and ubiquitin-AMC hydrolysis assay identified cinobufotalin (CBF), an anti-tumor drug, maybe a USP36 inhibitor by inhibiting its deubiquitination activity. CBF significantly prohibited proliferation, migration, invasion, and stemness of HCT116 cells and reversed Oxa-resistance, whereas enforced expression of USP36 blocked these effects. Moreover, in vivo analyses confirmed the oncogenic role of USP36 and the therapeutic potential of CBF in the malignancy of colon cancer. In conclusion, CBF may be a promising therapeutic agent for colon cancer due to its regulation of the USP36/c-Myc axis.

USP43 impairs cisplatin sensitivity in epithelial ovarian cancer through HDAC2-dependent regulation of Wnt/β-catenin signaling pathway

Epithelial ovarian cancer (EOC) is the leading cause of cancer death all over the world. USP43 functions as a tumor promoter in various malignant cancers. Nevertheless, the biological roles and mechanisms of USP43 in EOC remain unknown. In this study, USP43 was highly expressed in EOC tissues and cells, and high expression of USP43 were associated with a poor prognosis of EOC. USP43 overexpression promoted EOC cell proliferation, enhanced the ability of migration and invasion, decreased cisplatin sensitivity and inhibited apoptosis. Knockdown of USP43 in vitro effectively retarded above malignant progression of EOC. In vivo xenograft tumors, silencing USP43 slowed tumor growth and enhanced cisplatin sensitivity. Mechanistically, USP43 inhibited HDAC2 degradation and enhanced HDAC2 protein stability through its deubiquitylation function. USP43 diminished the sensitivity of EOC cells to cisplatin through activation of the Wnt/β-catenin signaling pathway mediated by HDAC2. Taken together, the data in this study revealed the functions of USP43 in proliferation, migration, invasion, chemoresistance of EOC cells, and the mechanism of HDAC2-mediated Wnt/β-catenin signaling pathway. Thus, USP43 might serve as a potential target for the control of ovarian cancer progression.

Investigating USP42 Mutation as Underlying Cause of Familial Non-Medullary Thyroid Carcinoma

In a family with Familial Non-Medullary Thyroid Carcinoma (FNMTC), our investigation using Whole-Exome Sequencing (WES) uncovered a novel germline USP42 mutation [p.(Gly486Arg)]. USP42 is known for regulating p53, cell cycle arrest, and apoptosis, and for being reported as overexpressed in breast and gastric cancer patients. Recently, a USP13 missense mutation was described in FNMTC, suggesting a potential involvement in thyroid cancer. Aiming to explore the USP42 mutation as an underlying cause of FNMTC, our team validated the mutation in blood and tissue samples from the family. Using immunohistochemistry, the expression of USP42, Caspase-3, and p53 was assessed. The USP42 gene was silenced in human thyroid Nthy-Ori 3-1 cells using siRNAs. Subsequently, expression, viability, and morphological assays were conducted. p53, Cyclin D1, p21, and p27 proteins were evaluated by Western blot. USP42 protein was confirmed in all family members and was found to be overexpressed in tumor samples, along with an increased expression of p53 and cleaved Caspase-3. siRNA-mediated USP42 downregulation in Nthy-Ori 3-1 cells resulted in reduced cell viability, morphological changes, and modifications in cell cycle-related proteins. Our results suggest a pivotal role of USP42 mutation in thyroid cell biology, and this finding indicates that USP42 may serve as a new putative target in FNMTC.

TEAD4: A key regulator of tumor metastasis and chemoresistance - Mechanisms and therapeutic implications

Cancer metastasis is a complex process influenced by various factors, including epithelial-mesenchymal transition (EMT), tumor cell proliferation, tumor microenvironment, and cellular metabolic status, which remains a significant challenge in clinical oncology, accounting for a majority of cancer-related deaths. TEAD4, a key mediator of the Hippo signaling pathway, has been implicated in regulating these factors that are all critical in the metastatic cascade. TEAD4 drives tumor metastasis and chemoresistance, and its upregulation is associated with poor prognosis in many types of cancers, making it an attractive target for therapeutic intervention. TEAD4 promotes EMT by interacting with coactivators and activating the transcription of genes involved in mesenchymal cell characteristics and extracellular matrix remodeling. Additionally, TEAD4 enhances the stemness of cancer stem cells (CSCs) by regulating the expression of genes associated with CSC maintenance. TEAD4 contributes to metastasis by modulating the secretion of paracrine factors and promoting heterotypic cellular communication. In this paper, we highlight the central role of TEAD4 in cancer metastasis and chemoresistance and its impact on various aspects of tumor biology. Understanding the mechanistic basis of TEAD4-mediated processes can facilitate the development of targeted therapies and combination approaches to combat cancer metastasis and improve treatment outcomes.

USP3 inhibition is Active Against Chemo-resistant Hepatocellular Carcinoma Anchorage-independent Growth via Suppressing Wnt/β-catenin

BACKGROUND

USPs are a family of enzymes that regulate protein degradation, and their dysregulation has been implicated in the development and progression of cancer.

AIMS

This study aimed to determine whether ubiquitin-specific proteases 3 (USP3) could be a potential target for therapy in hepatocellular carcinoma (HCC), particularly in resistant HCC. This study systematically investigated the role of USP3 in HCC, with a focus on chemo-resistant HCC cells.

METHODS

The level of USP3 from clinical samples was measured using an ELISA assay. Cell proliferation, apoptosis, migration, and anchorage-independent colony formation assays were performed. Transfection was performed to knock down USP3 expression and measure β-catenin activity, and real-time PCR was used to measure levels of MYC and CYCLIN D1 genes.

RESULTS

USP3 protein was upregulated in HCC tissues, but its upregulation was not associated with clinicopathology. USP3 knockdown had a similar inhibitory effect on growth in both sensitive and resistant HCC cells, did not affect migration, and induced apoptosis in sensitive but not resistant HCC cells. Furthermore, USP3 knockdown was more effective in suppressing anchorage-independent colony formation in chemoresistant HCC cells compared to their chemo-sensitive counterparts. Pearson correlation coefficient analysis revealed a strong positive correlation between USP3 and CTNNB1, and consistently, USP3 knockdown reduced the levels and activities of β-catenin in HCC cells. Using a Wnt activator (lithium) in rescue studies significantly reversed the inhibitory effects of USP3 knockdown.

CONCLUSION

The findings suggest that inhibiting USP3 is an effective strategy against cancer stem cells and chemo-resistant HCC cells.

High USP32 expression contributes to cancer progression and is correlated with immune infiltrates in hepatocellular carcinoma

BACKGROUND

Ubiquitin-specific protease 32 (USP32) is a highly conserved gene that promotes cancer progression. However, its role in hepatocellular carcinoma (HCC) is not well understood. The aim of this project is to explore the clinical significance and functions of USP32 in HCC.

METHODS

The expression of USP32 in HCC was evaluated using data from TCGA, GEO, TISCH, tissue microarray, and human HCC samples from our hospital. Survival analysis, PPI analysis and GSEA analysis were performed to evaluate USP32-related clinical significance, key molecules and enrichment pathways. Using the ssGSEA algorithm and TIMER, we investigated the relationships between USP32 and immune infiltrates in the TME. Univariate and multivariate Cox regression analyses were then used to identify key USP32-related immunomodulators and constructed a USP32-related immune prognostic model. Finally, CCK8, transwell and colony formation assays of HCC cells were performed and an HCC nude mouse model was established to verify the oncogenic role of USP32.

RESULTS

USP32 is overexpressed in HCC and its expression is an independent predictive factor for outcomes of HCC patients. USP32 is associated with pathways related to cell behaviors and cancer signaling, and its expression is significantly correlated with the infiltration of immune cells in the TME. We also successfully constructed a USP32-related immune prognostic model using 5 genes. Wet experiments confirmed that knockdown of USP32 could repress the proliferation, colony formation and migration of HCC cells in vitro and inhibit tumor growth in vivo.

CONCLUSION

USP32 is highly expressed in HCC and closely correlates with the TME of HCC. It is a potential target for improving the efficacy of chemotherapy and developing new strategies for targeted therapy and immunotherapy in HCC.

Ubiquitin-specific peptidase 1: assessing its role in cancer therapy

Reversible protein ubiquitination represents an essential determinator of cellular homeostasis, and the ubiquitin-specific enzymes, particularly deubiquitinases (DUBs), are emerging as promising targets for drug development. DUBs are composed of seven different subfamilies, out of which ubiquitin-specific proteases (USPs) are the largest family with 56 members. One of the well-characterized USPs is USP1, which contributes to several cellular biological processes including DNA damage response, immune regulation, cell proliferation, apoptosis, and migration. USP1 levels and activity are regulated by multiple mechanisms, including transcription regulation, phosphorylation, autocleavage, and proteasomal degradation, ensuring that the cellular function of USP1 is performed in a suitably modulated spatio-temporal manner. Moreover, USP1 with deregulated expression and activity are found in several human cancers, indicating that targeting USP1 is a feasible therapeutic approach in anti-cancer treatment. In this review, we highlight the essential role of USP1 in cancer development and the regulatory landscape of USP1 activity, which might provide novel insights into cancer treatment.

Functionalized Gold Nanoparticles Suppress the Proliferation of Human Lung Alveolar Adenocarcinoma Cells by Deubiquitinating Enzymes Inhibition

Functionalized gold nanoparticles (AuNPs) are widely used in therapeutic applications, but little is known regarding the impact of their surface functionalization in the process of toxicity against cancer cells. This study investigates the anticancer effects of 5 nm spherical AuNPs functionalized with tannate, citrate, and PVP on deubiquitinating enzymes (DUBs) in human lung alveolar adenocarcinoma (A549) cells. Our findings show that functionalized AuNPs reduce the cell viability in a concentration- and time-dependent manner as measured by modified lactate dehydrogenase (mLDH) and 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assays. An increased generation of intracellular reactive oxygen species (ROS) and depletion of glutathione (GSH/GSSG) ratio was observed with the highest AuNP concentration of 10 μg/mL. The expression of DUBs such as ubiquitin specific proteases (USP7, USP8, and USP10) was slightly inhibited when treated with concentrations above 2.5 μg/mL. Moreover, functionalized AuNPs showed an inhibitory effect on protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) and wingless-related integration site (Wnt) signaling proteins, and this could further trigger mitochondrial related-apoptosis by the upregulation of caspase-3, caspase-9, and PARP in A549 cells. Furthermore, our study shows a mechanistic understanding of how functionalized AuNPs inhibit the DUBs, consequently suppressing cell proliferation, and can be modulated as an approach toward anticancer therapy. The study also warrants the need for future work to investigate the effect of functionalized AuNPs on DUB on other cancer cell lines both in vitro and in vivo.

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.

USP32 deubiquitinase: cellular functions, regulatory mechanisms, and potential as a cancer therapy target

An essential protein regulatory system in cells is the ubiquitin-proteasome pathway. The substrate is modified by the ubiquitin ligase system (E1-E2-E3) in this pathway, which is a dynamic protein bidirectional modification regulation system. Deubiquitinating enzymes (DUBs) are tasked with specifically hydrolyzing ubiquitin molecules from ubiquitin-linked proteins or precursor proteins and inversely regulating protein degradation, which in turn affects protein function. The ubiquitin-specific peptidase 32 (USP32) protein level is associated with cell cycle progression, proliferation, migration, invasion, and other cellular biological processes. It is an important member of the ubiquitin-specific protease family. It is thought that USP32, a unique enzyme that controls the ubiquitin process, is closely linked to the onset and progression of many cancers, including small cell lung cancer, gastric cancer, breast cancer, epithelial ovarian cancer, glioblastoma, gastrointestinal stromal tumor, acute myeloid leukemia, and pancreatic adenocarcinoma. In this review, we focus on the multiple mechanisms of USP32 in various tumor types and show that USP32 controls the stability of many distinct proteins. Therefore, USP32 is a key and promising therapeutic target for tumor therapy, which could provide important new insights and avenues for antitumor drug development. The therapeutic importance of USP32 in cancer treatment remains to be further proven. In conclusion, there are many options for the future direction of USP32 research.

Risk of secondary tumours in patients with non-metastatic and metastatic human retinoblastoma

BACKGROUND

Retinoblastoma is an intraocular cancer in children and infants. Despite all the available treatment options and high survival rates in children with retinoblastoma, exposure to secondary tumours in adulthood is one of the concerns that physicians face. In many cases, dysfunction of the RB1 gene is the main cause of secondary tumours due to retinoblastoma. Therefore, the aim of this study was to evaluate the incidence of other secondary tumours in children with retinoblastoma.

METHODS

In this regard, we performed continuous and integrated bioinformatics analyses to find genes, protein products, and signal pathways involved in other cancers.

RESULTS

1170 high-expression genes and 960 low-expression genes between non-invasive and invasive retinoblastoma were isolated. After examining the signal pathways, we observed bladder cancer and small cell lung cancer in the overexpressed genes. We also observed 5 cancers of endometriosis, prostate, non-small cell lung cancer, glioblastoma and renal cell carcinoma in low-expression genes. Based on the P-value index, non-small cell lung cancer, prostate and bladder cancers had the highest risk, and endometriosis cancer showed a lower probability of developing a secondary tumour in patients with retinoblastoma. In addition, the network between proteins also showed us that TP53, CDK2, SRC, MAPK1 proteins with high expression and JUN, HSP90AA1, and UBC proteins with low-expression play a significant role in candidate cancers.

CONCLUSION

Lastly, we used continuous bioinformatics analysis to show that seven cancers are strongly linked to retinoblastoma cancer. Of course, more research is needed to find the best way to care for children who have been treated for retinoblastoma.

A risk signature of ubiquitin-specific protease family predict the prognosis and therapy of kidney cancer patients

Ubiquitin-specific proteases (USPs) are closely related to protein fate and cellular processes through various molecular signalling pathways, including DNA damage repair, p53, and transforming growth factor-β (TGF-β) pathways. In recent years, increasing evidence has revealed the pivotal role of ubiquitination in tumorigenesis of KIRC. However, USPs' molecular mechanism and clinical relevance in kidney cancer still need further exploration. Our study first determined prognosis-related ubiquitin-specific proteases (PRUSPs) in KIRC. We found these genes co-expressed with each other and might regulate different substrates. Based on the USPs' expression, the PRUSPs risk signature was constructed to predict the survival probability of KIRC patients. The patients in high-PRUSPs-risk group showed a low survival rate. ROC and calibration curve indicated a discriminate capacity of the signature, and uni-/multi-variate Cox regression analysis revealed that the PRUSPs score is an independent prognostic factor. In different KIRC clinical subgroups and external validation cohorts (including E-MTAB-1980 and TCGA-KIRP cohorts), the PRUSPs risk signature showed strong robustness and practicability. Further analysis found that high-risk group showed activation of immune-related pathways and high PD-1/CTLA4 expression, revealing that high-risk patients might be sensitive to immunotherapy. In summary, we constructed the USPs risk signature to predict kidney cancer prognosis, which provided the theoretical foundation for further clinical or pre-clinical experiments.

The emerging roles and mechanism of N6-methyladenosine (m6A) modifications in urologic tumours progression

Prostate cancer (PCa), bladder cancer (BC), and renal cell cancer (RCC) are the most common urologic tumours in males. N6-methyladenosine (m⁶A), adenosine N6 methylation, is the most prevalent RNA modification in mammals. Increasing evidence suggests that m⁶A plays a crucial role in cancer development. In this review, we comprehensively analyzed the influence of m⁶A methylation on Prostate cancer, bladder cancer, and renal cell cancer and the relationship between the expression of relevant regulatory factors and their development and occurrence, which provides new insights and approaches for the early clinical diagnosis and targeted therapy of urologic malignancies.

Targeted therapy based on ubiquitin-specific proteases, signalling pathways and E3 ligases in non-small-cell lung cancer

Lung cancer is one of the most common malignant tumours worldwide, with the highest mortality rate. Approximately 1.6 million deaths owing to lung cancer are reported annually; of which, 85% of deaths occur owing to non-small-cell lung cancer (NSCLC). At present, the conventional treatment methods for NSCLC include radiotherapy, chemotherapy, targeted therapy and surgery. However, drug resistance and tumour invasion or metastasis often lead to treatment failure. The ubiquitin–proteasome pathway (UPP) plays an important role in the occurrence and development of tumours. Upregulation or inhibition of proteins or enzymes involved in UPP can promote or inhibit the occurrence and development of tumours, respectively. As regulators of UPP, ubiquitin-specific proteases (USPs) primarily inhibit the degradation of target proteins by proteasomes through deubiquitination and hence play a carcinogenic or anticancer role. This review focuses on the role of USPs in the occurrence and development of NSCLC and the potential of corresponding targeted drugs, PROTACs and small-molecule inhibitors in the treatment of NSCLC.

Ubiquitin-specific peptidases: Players in bone metabolism

Osteoporosis is an ageing-related disease, that has become a major public health problem and its pathogenesis has not yet been fully elucidated. Substantial evidence suggests a strong link between overall age-related disease progression and epigenetic modifications throughout the life cycle. As an important epigenetic modification, ubiquitination is extensively involved in various physiological processes, and its role in bone metabolism has attracted increasing attention. Ubiquitination can be reversed by deubiquitinases, which counteract protein ubiquitination degradation. As the largest and most structurally diverse cysteinase family of deubiquitinating enzymes, ubiquitin-specific proteases (USPs), comprising the largest and most structurally diverse cysteine kinase family of deubiquitinating enzymes, have been found to be important players in maintaining the balance between bone formation and resorption. The aim of this review is to explore recent findings highlighting the regulatory functions of USPs in bone metabolism and provide insight into the molecular mechanisms governing their actions during bone loss. An in-deep understanding of USPs-mediated regulation of bone formation and bone resorption will provide a scientific rationale for the discovery and development of novel USP-targeted therapeutic strategies for osteoporosis.

Histone Modifications Represent a Key Epigenetic Feature of Epithelial-to-Mesenchyme Transition in Pancreatic Cancer

Pancreatic cancer is one of the most lethal malignant diseases due to its high invasiveness, early metastatic properties, rapid disease progression, and typically late diagnosis. Notably, the capacity for pancreatic cancer cells to undergo epithelial-mesenchymal transition (EMT) is key to their tumorigenic and metastatic potential, and is a feature that can explain the therapeutic resistance of such cancers to treatment. Epigenetic modifications are a central molecular feature of EMT, for which histone modifications are most prevalent. The modification of histones is a dynamic process typically carried out by pairs of reverse catalytic enzymes, and the functions of these enzymes are increasingly relevant to our improved understanding of cancer. In this review, we discuss the mechanisms through which histone-modifying enzymes regulate EMT in pancreatic cancer.

Ubiquitin-Specific Proteases as Potential Therapeutic Targets in Bladder Cancer—In Vitro Evaluation of Degrasyn and PR-619 Activity Using Human and Canine Models

Background: The inhibition of ubiquitin-specific proteases (USPs) is a novel and promising direction in the development of molecularly targeted therapies in oncology. The aim of the present study was to examine whether Degrasyn could be a potential therapeutic agent against bladder cancer (BC). Also, we aimed to determine whether Degrasyn is more effective in terms of anti-cancer activity compared to the non-selective DUB inhibitor PR-619. To facilitate the translational value of the obtained results, our experiments were performed using both human and canine in vitro models of BC. Methods: Human T24 (urothelial grade III BC) and SV-HUC-1 (non-tumorigenic urothelial cell line), as well as canine K9TCC-PU-NK and RDSVS-TCC1 (both derived from invasive grade III urothelial bladder tumors) cell lines, were used in the present study. Cell proliferation was determined using the MTT assay and Ki-67 proliferation assay, and the level of apoptosis induced by Degrasyn and PR-619 was evaluated by Annexin V-FITC staining and caspase 3/7 activation assay. Western blot was used to assess DNA damage and key proteins involved in apoptosis. Results: Degrasyn inhibited the proliferation of all BC cell lines in a concentration- and time-dependent manner. Lower concentrations of Degrasyn were more potent against human and canine BC cell lines compared to PR-619. Degrasyn induced caspase-dependent apoptosis and triggered DNA damage. PR-619 did not show a significant pro-apoptotic effect. Conclusions: Our results demonstrate that Degrasyn significantly impairs the growth of in vitro models of human and canine BC. Selective USP inhibition with Degrasyn seems to be more effective in reducing BC cell proliferation and inducing apoptosis and DNA damage than non-selective USP inhibition with PR-619.

Integrative Multiomics to Dissect the Lung Transcriptional Landscape of Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) remains an incurable and often fatal disease despite currently available therapies. Multiomics systems biology analysis can shed new light on PAH pathobiology and inform translational research efforts. Using RNA sequencing on the largest PAH lung biobank to date (96 disease and 52 control), we aim to identify gene co-expression network modules associated with PAH and potential therapeutic targets. Co-expression network analysis was performed to identify modules of co-expressed genes which were then assessed for and prioritized by importance in PAH, regulatory role, and therapeutic potential via integration with clinicopathologic data, human genome-wide association studies (GWAS) of PAH, lung Bayesian regulatory networks, single-cell RNA-sequencing data, and pharmacotranscriptomic profiles. We identified a co-expression module of 266 genes, called the pink module, which may be a response to the underlying disease process to counteract disease progression in PAH. This module was associated not only with PAH severity such as increased PVR and intimal thickness, but also with compensated PAH such as lower number of hospitalizations, WHO functional class and NT-proBNP. GWAS integration demonstrated the pink module is enriched for PAH-associated genetic variation in multiple cohorts. Regulatory network analysis revealed that BMPR2 regulates the main target of FDA-approved riociguat, GUCY1A2, in the pink module. Analysis of pathway enrichment and pink hub genes (i.e. ANTXR1 and SFRP4) suggests the pink module inhibits Wnt signaling and epithelial-mesenchymal transition. Cell type deconvolution showed the pink module correlates with higher vascular cell fractions (i.e. myofibroblasts). A pharmacotranscriptomic screen discovered ubiquitin-specific peptidases (USPs) as potential therapeutic targets to mimic the pink module signature. Our multiomics integrative study uncovered a novel gene subnetwork associated with clinicopathologic severity, genetic risk, specific vascular cell types, and new therapeutic targets in PAH. Future studies are warranted to investigate the role and therapeutic potential of the pink module and targeting USPs in PAH.

Ubiquitin-Specific Protease 43 Impacts Pancreatic Ductal Adenocarcinoma Prognosis by Altering Its Proliferation and Infiltration of Surrounding Immune Cells

Background

Pancreatic ductal adenocarcinoma (PDAC) is a devastating cancer, and the therapy options for PDAC remain restricted. The distinctive tumor immunological microenvironment (TIME) of PDAC, comprising a high number of stromal cells and a limited infiltration of cytotoxic T lymphocytes (CTLs), rendered immunotherapy ineffective. The protein level of ubiquitin-specific protease 43 (USP43) was a prognostic predictor in numerous cancers; however, its function in PDAC is limited. This article focuses on the influence of USP43 expression on PDAC prognosis and TIME alteration.

Methods

Based on TCGA database and tissue microarray staining, the expression of USP43 in PDAC was evaluated. The association between USP43 and prognosis was then investigated using tissue samples and online databases. In PDAC tumor tissues, the correlation between USP43 expression and clinicopathological characteristics, immune cell infiltration, and prognosis was investigated. The expression of USP43 in PDAC cell lines was evaluated using quantitative polymerase chain reaction. Using a cell counting kit-8 (CCK-8) and a cell colony formation test, the viability of the cells was determined. On the basis of online databases and tissue samples, the link between USP43 and immune cell infiltration around PDAC was also examined. For statistical analyses, the software GraphPad, R, and SPSS 26.0 were utilized.

Results

The expression of USP43 was considerably higher in PDAC compared to normal pancreatic tissue in both the TCGA database and the tissue microarrays of PDAC patients (P < 0.001). High USP43 expression was associated with poor overall survival in both the TCGA database and the tissue microarray of PDAC patients (P = 0.046 and 0.021, respectively). USP43 overexpression promoted PANC-1 cell proliferation (P = 0.0018), but USP43 knockdown decreased PANC02 cell proliferation (P < 0.001). According to the TCGA database, USP43 is associated with T cell activation and inhibits CD8⁺ T cell activation in PDAC, as proven by a study of cell lines. Moreover, in both TCGA and PDAC cell lines, USP43 expression was negatively linked with the chemokine signaling pathway.

Conclusions

Overexpression of USP43 is a potential prognostic indicator for PDAC patients. USP43 is a potential biomarker associated with T cell activation, suppression of CD8⁺ T cell enrichment, and the cytokine signal pathway. Future multicenter studies are needed to confirm our findings and their potential application in the treatment of PDAC patients.

Post-Translational Modification of ZEB Family Members in Cancer Progression

Post-translational modification (PTM), the essential regulatory mechanisms of proteins, play essential roles in physiological and pathological processes. In addition, PTM functions in tumour development and progression. Zinc finger E-box binding homeobox (ZEB) family homeodomain transcription factors, such as ZEB1 and ZEB2, play a pivotal role in tumour progression and metastasis by induction epithelial-mesenchymal transition (EMT), with activation of stem cell traits, immune evasion and epigenetic reprogramming. However, the relationship between ZEB family members' post-translational modification (PTM) and tumourigenesis remains largely unknown. Therefore, we focussed on the PTM of ZEBs and potential therapeutic approaches in cancer progression. This review provides an overview of the diverse functions of ZEBs in cancer and the mechanisms and therapeutic implications that target ZEB family members' PTMs.

Emerging potential of ubiquitin-specific proteases and ubiquitin-specific proteases inhibitors in breast cancer treatment

Breast cancer is the most frequently diagnosed cancer in women, accounting for 30% of new diagnosing female cancers. Emerging evidence suggests that ubiquitin and ubiquitination played a role in a number of breast cancer etiology and progression processes. As the primary deubiquitinases in the family, ubiquitin-specific peptidases (USPs) are thought to represent potential therapeutic targets. The role of ubiquitin and ubiquitination in breast cancer, as well as the classification and involvement of USPs are discussed in this review, such as USP1, USP4, USP7, USP9X, USP14, USP18, USP20, USP22, USP25, USP37, and USP39. The reported USPs inhibitors investigated in breast cancer were also summarized, along with the signaling pathways involved in the investigation and its study phase. Despite no USP inhibitor has yet been approved for clinical use, the biological efficacy indicated their potential in breast cancer treatment. With the improvements in phenotypic discovery, we will know more about USPs and USPs inhibitors, developing more potent and selective clinical candidates for breast cancer.

MIR99AHG inhibits EMT in pulmonary fibrosis via the miR-136-5p/USP4/ACE2 axis

Background

Long non-coding RNAs (lncRNAs) are closely related to the occurrence and development of cancer. Abnormally expressed lncRNA can be used as a diagnostic marker for cancer. In this study, we aim to investigate the clinical significance of MIR99AHG expression in lung adenocarcinoma (LUAD), and its biological roles in LUAD progression.

Methods

The relative expression of MIR99AHG in LUAD tissues and cell lines was analyzed using public databases and RT-qPCR. The biological functions of MIR99AHG were investigated using a loss-of-function approach. The effect of MIR99AHG on lung fibrosis was assessed by scratch assay, invasion assay and lung fibrosis rat model. FISH, luciferase reporter assay and immunofluorescence were performed to elucidate the underlying molecular mechanisms.

Results

LncRNA MIR99AHG expression level was downregulated in LUAD tissues and cell lines. Low MIR99AHG levels were associated with poorer patient overall survival. Functional analysis showed that MIR99AHG is associated with the LUAD malignant phenotype in vitro and in vivo. Further mechanistic studies showed that, MIR99AHG functions as a competitive endogenous RNA (ceRNA) to antagonize miR-136-5p-mediated ubiquitin specific protease 4 (USP4) degradation, thereby unregulated the expression of angiotensin-converting enzyme 2 (ACE2), a downstream target gene of USP4, which in turn affected alveolar type II epithelial cell fibrosis and epithelial–mesenchymal transition (EMT). In summary, the MIR99AHG/miR-136-5p/USP4/ACE2 signalling axis regulates lung fibrosis and EMT, thus inhibiting LUAD progression.

Conclusion

This study showed that downregulated MIR99AHG leads to the development of pulmonary fibrosis. Therefore, overexpression of MIR99AHG may provide a new approach to preventing LUAD progression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03633-y.

The role of CircRNA/miRNA/mRNA axis in breast cancer drug resistance

Multidrug resistance is one of the major obstacles in the treatment of cancers. This undesirable feature increases the mortality rate of cancers, including breast cancer. Circular RNA (CircRNA)/microRNA (miRNA)/messenger RNA (mRNA) is one of the important axes with major roles in the promotion and resistance of breast cancer. This heterogeneous pathway includes mRNA of oncogenes and tumor suppressors, which are controlled by miRNAs and CircRNAs. Unfortunately, this network could be easily deregulated, resulting in drug resistance and tumor development. Therefore, understanding these dysregulations may thus help to identify effective therapeutic targets. On this basis, we try to review the latest findings in the field, which could help us to better comprehend this significant axis in breast cancer.

LncRNA MNX1-AS1 sustains inactivation of Hippo pathway through a positive feedback loop with USP16/IGF2BP3 axis in gallbladder cancer

The long non-coding RNAs (lncRNAs) have been implicated in multiple human cancers, which may offer great potential as putative targets for cancer diagnosis and treatment. However, the roles of most lncRNAs in gallbladder cancer (GBC) remain poorly understood. The objective of this research involves investigating the clinical implications and underlying mechanism of lncRNA motor neuron and pancreas homeobo×1 antisense RNA 1 (MNX1-AS1) in GBC. This study shows that MNX1-AS1 expression is elevated in the tissues of GBC patients, and is strongly associated with reduced patient survival. Functionally, MNX1-AS1 significantly stimulates the proliferation and metastasis of GBC cells in vitro and in vivo. Mechanistically, MNX1-AS1 is transcriptionally activated by TEA domain family member 4 (TEAD4), and suppresses insulin-like growing factor 2 mRNA-binding protein 3 (IGF2BP3) degradation by recruiting ubiquitin specific peptidase 16 (USP16). Furthermore, MNX1-AS1/IGF2BP3 axis inhibits the Hippo signaling pathway and subsequently activates TEAD4, thereby forming a positive feedback loop. According to our results, MNX1-AS1 facilitates tumorigenesis, progression and metastasis of GBC through a MNX1-AS1/IGF2BP3/Hippo pathway positive feedback loop, which could be both diagnostically and therapeutically helpful in GBC.

USP13 genetics and expression in a family with thyroid cancer

PURPOSE

Papillary thyroid carcinoma (PTC) is the most common type of thyroid carcinoma and its incidence has greatly increased in the last 30 years. Ubiquitin-specific protease 13 (USP13) is a class of deubiquitinating enzymes (DUBs) and plays an important role in cellular functions such as cell cycle regulation, DNA damage repair, and different cell signaling pathways. Studies regarding the role of USP13 in cancer development and progression are divergent and there are no previous data regarding the role of USP13 gene in PTCs. In this study, we investigated the genetic cause of PTC diagnosed in multiple members of a Brazilian family.

METHODS

Whole exome sequencing (WES) was performed to identify the genetic cause of PTC. Cycloheximide chase assay and clonogenic assay were performed to study USP13 stability and function in vitro.

RESULTS

WES analysis identified a heterozygous missense variant c.1483G > A (p.V495M) in the USP13 gene that fully segregates with the disease. In silico modeling suggests that this variant may cause protein structural perturbations. USP13 overexpression increased the potential of a single cell to form colonies. The USP13 c.1483G > A variant enhanced the effects seen in USP13 overexpression and preserved protein stability for longer hours compared to the non-mutated USP13 protein.

CONCLUSION

Our study suggests that USP13 overexpression may play a role in tumorigenesis of PTCs; and that the USP13 p.V495M (c.1483G > A) variant enhances USP13 estability.

IL-33 biology in cancer: An update and future perspectives

Interleukin-33 (IL-33) is a member of the IL-1 family of cytokines that is constitutively expressed in the nucleus of epithelial, endothelial and fibroblast-like cells. Upon cell stress, damage or necrosis, IL-33 is released into the cytoplasm to exert its prime role as an alarmin by binding to its specific receptor moiety, ST2. IL-33 exhibits pleiotropic function in inflammatory diseases and particularly in cancer. IL-33 may play a dual role as both a pro-tumorigenic and anti-tumorigenic cytokine, dependent on tumor and cellular context, expression levels, bioactivity and the nature of the inflammatory environment. In this review, we discuss the differential contribution of IL-33 to malignant or inflammatory conditions, its multifaceted effects on the tumor microenvironment, while providing possible explanations for the discrepant findings described in the literature. Additionally, we examine the emerging and divergent functions of IL-33 in the nucleus, and aspects of IL-33 biology that are currently under-addressed.

Ubiquitin specific peptidase 11 as a novel therapeutic target for cancer management

Ubiquitination is a critical biological process in post-translational modification of proteins and involves multiple signaling pathways in protein metabolism, apoptosis, DNA damage, cell-cycle progression, and cancer development. Deubiquitinase, a specific enzyme that regulates the ubiquitination process, is also thought to be closely associated with the development and progression of various cancers. In this article, we systematically review the emerging role of the deubiquitinase ubiquitin-specific peptidase 11 (USP11) in many cancer-related pathways. The results show that USP11 promotes or inhibits the progression and chemoresistance of different cancers, including colorectal, breast, ovarian, and hepatocellular carcinomas, via deubiquitinating several critical proteins of cancer-related pathways. We initially summarize the role of USP11 in different cancers and further discuss the possibility of USP11 as a therapeutic strategy.

Responsiveness to DDAVP in Cushing's disease is associated with USP8 mutations through enhancing AVPR1B promoter activity

PURPOSE

To clarify the characteristics of Cushing's disease (CD) patients who respond to the desmopressin (DDAVP) test and its underlying mechanisms.

METHODS

Forty-seven patients with CD who underwent DDAVP testing were included. Patients were divided into two groups: DDAVP test (+) (adrenocorticotropic hormone [ACTH] levels increased by ≥ 1.5-fold during the DDAVP test) and DDAVP test (-) (ACTH levels increased by < 1.5-fold). AVP receptor expression levels in these tumors were quantified using quantitative RT-PCR and immunohistochemistry. AVP receptor promoter activity was analyzed using a dual-luciferase reporter assay system.

RESULTS

Females (96.9%) and USP8 mutants (85.7%) were more prevalent in the DDAVP test (+) than in the DDAVP test (-). Indeed, the ACTH and cortisol responsiveness to DDAVP was greater in USP8 mutation positive tumors than that in USP8 wild type tumors (3.0-fold vs. 1.3-fold, 1.6-fold vs. 1.1-fold, respectively). Responsiveness to DDAVP was correlated with the expression levels of AVPR1B, but not with those of AVPR2. Comparably, Avpr1b promoter activity was enhanced by the overexpression of mutant USP8 compared to the wild type.

CONCLUSIONS

We found that the responsiveness of ACTH to DDAVP in CD was greater in tumors with USP8 mutations. The present data suggest that USP8 mutations upregulate the AVPR1B promoter activity. Additionally, we showed that the DDAVP test can predict the presence of USP8 mutations.

Secreted Amyloid Precursor Protein Alpha, a Neuroprotective Protein in the Brain Has Widespread Effects on the Transcriptome and Proteome of Human Inducible Pluripotent Stem Cell-Derived Glutamatergic Neurons Related to Memory Mechanisms

Secreted amyloid precursor protein alpha (sAPPα) processed from a parent human brain protein, APP, can modulate learning and memory. It has potential for development as a therapy preventing, delaying, or even reversing Alzheimer’s disease. In this study a comprehensive analysis to understand how it affects the transcriptome and proteome of the human neuron was undertaken. Human inducible pluripotent stem cell (iPSC)-derived glutamatergic neurons in culture were exposed to 1 nM sAPPα over a time course and changes in the transcriptome and proteome were identified with RNA sequencing and Sequential Window Acquisition of All THeoretical Fragment Ion Spectra-Mass Spectrometry (SWATH-MS), respectively. A large subset (∼30%) of differentially expressed transcripts and proteins were functionally involved with the molecular biology of learning and memory, consistent with reported links of sAPPα to memory enhancement, as well as neurogenic, neurotrophic, and neuroprotective phenotypes in previous studies. Differentially regulated proteins included those encoded in previously identified Alzheimer’s risk genes, APP processing related proteins, proteins involved in synaptogenesis, neurotransmitters, receptors, synaptic vesicle proteins, cytoskeletal proteins, proteins involved in protein and organelle trafficking, and proteins important for cell signalling, transcriptional splicing, and functions of the proteasome and lysosome. We have identified a complex set of genes affected by sAPPα, which may aid further investigation into the mechanism of how this neuroprotective protein affects memory formation and how it might be used as an Alzheimer’s disease therapy.

A positive feedback loop between LINC01605 and NF-κB pathway promotes tumor growth in nasopharyngeal carcinoma

zong non-coding RNAs (lncRNAs) have been identified as crucial effector in modulating the progression of assorted malignancies. In our study, the main aim was to unveil the role and the underlying regulatory mechanism of long intergenic non-protein coding RNA 1605 (LINC01605) in nasopharyngeal carcinoma (NPC). RT-qPCR analysis results suggested that LINC01605 was upregulated in NPC cells. According to the results of function experiments, LINC01605 promoted NPC cell proliferation and impeded cell apoptosis. The oncogenic role of LINC01605 in NPC was further validated by animal experiments. Additionally, we verified that LINC01605 regulated Ikbkb expression to promote the nuclear translocation of p65 and thereby activated the NF-κB pathway in NPC cells. Mechanism experiments further suggested that LINC01605 could regulate Ikbkb expression via sponging miR-942-5p. Moreover, LINC01605 recruited IGF2BP2 to stabilize ubiquitin-specific protease 3 (USP3) mRNA and thereby enhanced the stability of IkB subunit beta (IKKβ) protein. In addition, p65 acted as a transcription activator to upregulate LINC01605 in NPC cells. In conclusion, this study demonstrated a positive feedback loop between LINC01605 and the NF-κB signalling pathway that promoted NPC cell growth, thus providing new insights to better understand NPC.

MicroRNAs and Corresponding Targets in Esophageal Cancer as Shown In Vitro and In Vivo in Preclinical Models

Squamous cell carcinoma of the esophagus is associated with a dismal prognosis. Therefore, identification of new targets and implementation of new treatment modalities are issues of paramount importance. Based on a survey of the literature, we identified microRNAs conferring antitumoral activity in preclinical in vivo experiments. In the category of miRs targeting secreted factors and transmembrane receptors, four miRs were up-regulated and 10 were down-regulated compared with five out of nine in the category transcription factors, and six miRs were down-regulated in the category enzymes, including metabolic enzymes. The down-regulated miRs have targets which can be inhibited by small molecules or antibody-related entities, or re-expressed by reconstitution therapy. Up-regulated miRs have targets which can be reconstituted with small molecules or inhibited with antagomirs.

Imaging-Based Screening of Deubiquitinating Proteases Identifies Otubain-1 as a Stabilizer of c-MYC

The ubiquitin-proteasome pathway precisely controls the turnover of transcription factors in the nucleus, playing an important role in maintaining appropriate quantities of these regulatory proteins. The transcription factor c-MYC is essential for normal development and is a critical cancer driver. Despite being highly expressed in several tissues and malignancies, the c-MYC protein is also continuously targeted by the ubiquitin-proteasome pathway, which can either facilitate or inhibit c-MYC degradation. Deubiquitinating proteases can remove ubiquitin chains from target proteins and rescue them from proteasomal digestion. This study sought to determine novel elements of the ubiquitin-proteasome pathway that regulate c-MYC levels. We performed an overexpression screen with 41 human proteases to identify which deubiquitinases stabilize c-MYC. We discovered that the highly expressed Otubain-1 (OTUB1) protease increases c-MYC protein levels. Confirming its role in enhancing c-MYC activity, we found that elevated OTUB1 correlates with inferior clinical outcomes in the c-MYC-dependent cancer multiple myeloma, and overexpression of OTUB1 accelerates the growth of myeloma cells. In summary, our study identifies OTUB1 as a novel amplifier of the proto-oncogene c-MYC.

Biology of PEST‐Containing Nuclear Protein: A Potential Molecular Target for Cancer Research

PEST-containing nuclear protein (PCNP), a novel nuclear protein, is involved in vital cellular processes like cell proliferation and mediates tumorigenesis. PCNP is a short-living, small nuclear protein of only 178 amino acids with two remarkable PEST sequences that are rich in proline (P), glutamic acid (E), serine (S), and threonine (T). The current understanding of PCNP reveals that PCNP has the ability to interact with cell cycle regulatory proteins; tumor suppressors (p53 and pRB), and promoters (cyclin E and cyclin D) to determine the fate of tissues to facilitate the process of either apoptosis or cell proliferation. In many preclinical studies, it has been evaluated that PCNP expression has associations with the development and progression of various cancers like neuroblastoma, lung adenocarcinoma, and ovarian cancer. Based on these depicted novel roles of PCNP in cell cycleregulation and of PCNP in tumorigenesis, it is logical to consider PCNP as a potential molecular target for cancer research. The aim of the current communication is to present an update on PCNP research and discussion on the potential role of PCNP in cancer development with challenges and opportunities perspectives. Considering the available evidence as a baseline for our statement, we anticipate that in the future, new research insights will strengthen the aim to develop PCNP-based diagnostic and therapeutic approaches that will move the PCNP from the laboratory to the cancer clinic.

The Gene Expression Analysis of Peripheral Blood Monocytes From Psoriasis Vulgaris Patients With Different Traditional Chinese Medicine Syndromes

Psoriasis is chronic skin disease and an important health concern. Traditional Chinese Medicine (TCM) has shown great promise in the treatment of psoriasis. However, the correlation between TCM Syndromes and genomics of psoriasis has not been evaluated. Here, we analyzed gene expression profiling of monocytes from psoriasis vulgaris patients with different TCM syndrome types to reveal the molecular basis of different psoriasis syndromes. Of the 62 cases of psoriasis vulgaris recruited, 16, 23, and 23 cases were of blood-heat syndrome, blood stasis syndrome, and blood-dryness syndrome, respectively; 10 healthy controls were recruited as controls. Affymertix’s Gene Chip ®clariom D gene chip was used to detect the gene expression profile of peripheral blood monocytes collected from recruited individuals. Compared with the healthy control group, 1570 genes were up-regulated and 977 genes were down-regulated in the psoriasis vulgaris patients group; 798 genes and 108 genes were up- and down-regulated in the blood-heat syndrome group respectively; 319 and 433 genes were up- and down-regulated in the blood-dryness syndrome group, respectively; and 502 and 179 genes were up-and down-regulated in the blood-stasis syndrome group. Our analyses indicated not only common differential genes and pathways between psoriasis syndrome groups and healthy controls, but also syndrome-specific genes and pathways. The results of this study link the three syndromes at the gene level and will be useful for clarifying the molecular basis of TCM syndromes of psoriasis.

Clinical Trial Registration: (http://www.chictr.org.cn/showproj.aspx?proj=4390), identifier (ChiCTR-TRC-14005185).

LncRNA USP30-AS1 promotes the survival of acute myeloid leukemia cells by cis-regulating USP30 and ANKRD13A

Acute myeloid leukemia (AML) is a malignant tumor derived from leukemia stem cells, with complicated pathogenesis. LncRNAs play an important role in tumors genesis and progression. According to results from bioinformatics analysis, lncRNA USP30-AS1 is highly expressed in AML and both the high expression of USP30-AS1 and low methylation level at Cg03124318 locus of USP30-AS1 gene promoter are associated with poor prognosis of AML. This study knocked down and overexpressed USP30-AS1 to determine the roles in AML cell lines. High-throughput sequencing was performed to explore the genes regulated by USP30-AS1. Results showed that USP30-AS1 promoted AML cell viability and inhibited apoptosis. Genes regulated by USP30-AS1 are mainly related to genetic regulation and immune system. Among them, USP30 and ANKRD13A genes are close to USP30-AS1 gene in chromosome. Knockdown of USP30, but not ANKRD13A, abolished the cancer-promoting effects of USP30-AS1. ANKRD13A recognizes Lys-63-linked polyubiquitin chain in HLA-I. USP30-AS1 induced HLA-I internalization from the cell membrane by up-regulating ANKRD13A, which might induce the immune escape of AML cells. ChIP analysis revealed that the regulatory effects of USP30-AS1 on USP30 and ANKRD13A are associated with H3K4me3 and H3K27Ac. In summary, USP30-AS1 probably promotes AML cell survival by cis-regulating USP30 and ANKRD13A.

Inhibition of USP11 sensitizes gastric cancer to chemotherapy via suppressing RhoA and Ras-mediated signaling pathways

BACKGROUND

The poor outcomes in advanced gastric cancer (GC) necessitate alternative therapeutic strategy. Ubiquitin-specific protease 11 (USP11) has recently garnered attention as a therapeutic target in cancer because of its important regulatory role in cancer cell functions. Here, we revealed the expression, function and underlying molecular interactions of USP11 in gastric cancer.

METHODS

The expression of USP11 was analyzed using immunohistochemistry and ELISA. The loss-of function and gain-of function analysis of USP11 was performed using siRNA knockdown and plasmid overexpression approaches. The downstream molecules regulated by USP11 were determined using immunoblotting analysis.

RESULTS

USP11 was upregulated in ∼80% of gastric cancer patients, and the upregulation was associated with HER3 overexpression. In addition, USP11 level was not regulated by HER3 and vice versa. Functional studies demonstrated that USP11 overexpression promoted gastric cancer growth and migration, and alleviated toxicity-induced by chemotherapeutic drug. In contrast, USP11 depletion significantly inhibited gastric cancer growth, migration and survival, and augmented chemotherapeutic drug's efficacy. Gastric cancer cells with higher USP11 levels were more sensitive to USP11 inhibitions than cells with lower USP11 levels. Mechanism studies showed that USP11 depletion suppressed migration via RhoA-mediated pathway and inhibited growth and survival likely via Ras-mediated pathway.

CONCLUSIONS

Our work highlights the important role of USP11 in gastric cancer and therapeutic value of inhibiting USP11 to sensitize gastric cancer to chemotherapy.

USP8 regulates liver cancer progression via the inhibition of TRAF6-mediated signal for NF-κB activation and autophagy induction by TLR4

Herein, we aimed to elucidate the molecular and cellular mechanism in which ubiquitin-specific protease 8 (USP8) is implicated in liver cancer progression via TRAF6-mediated signal. USP8 induces the deubiquitination of TRAF6, TAB2, TAK1, p62, and BECN1, which are pivotal roles for NF-κB activation and autophagy induction. Notably, the LIHC patient with low USP8 mRNA expression showed markedly shorter survival time, whereas there was no significant difference in the other 18-human cancers. Importantly, the TCGA data analysis on LIHC and transcriptome analysis on the USP8 knockout (USP8KO) SK-HEP-1 cells revealed a significant correlation between USP8 and TRAF6, TAB2, TAK1, p62, and BECN1, and enhanced NF-κB-dependent and autophagy-related cancer progression/metastasis-related genes in response to LPS stimulation. Furthermore, USP8KO SK-HEP-1 cells showed an increase in cancer migration and invasion by TLR4 stimulation, and a marked increase of tumorigenicity and metastasis in xenografted NSG mice. The results demonstrate that USP8 is negatively implicated in the LIHC progression through the regulation of TRAF6-mediated signal for the activation of NF-κB activation and autophagy induction. Our findings provide useful insight into the LIHC pathogenesis of cancer progression.

The role of ubiquitin-specific peptidases in glioma progression

The balance between ubiquitination and deubiquitination is crucial for protein stability, function and location under physiological conditions. Dysregulation of E1/E2/E3 ligases or deubiquitinases (DUBs) results in malfunction of the ubiquitin system and is involved in many diseases. Increasing reports have indicated that ubiquitin-specific peptidases (USPs) play a part in the progression of many kinds of cancers and could be good targets for anticancer treatment. Glioma is the most common malignant tumor in the central nervous system. Clinical treatment for high-grade glioma is unsatisfactory thus far. Multiple USPs are dysregulated in glioma and have the potential to be therapeutic targets. In this review, we collected studies on the roles of USPs in glioma progression and summarized the mechanisms of USPs in glioma tumorigenesis, malignancy and chemoradiotherapy resistance.

Expression of Ubiquitin-specific protease 7 in oral squamous cell carcinoma promotes tumor cell proliferation and invasion

Oral Squamous Cell Carcinoma (OSCC) is the most common malignant cancer affecting oral cavity. Recent studies have demonstrated that Ubiquitin-specific protease 7 (USP7) was upregulated in several types of cancers. USP7 expression was associated with various proto-oncogenes and tumor suppressor genes. However, USP7 expression level and its functional role in OSCC is unclear. In the current study, we showed that USP7 expression in OSCC tissues was generally upregulated compared to normal adjacent tissues by using IHC. Furthermore, statistical analysis uncovered that USP7 expression was positively correlated with Ki-67, MMP2, VEGF in OSCC tissues. Importantly, high USP7 expression was significantly correlated with lymph node metastasis and histological differentiation in OSCC patients. So, our hypothesis is that USP7 plays a tumor-promoting role in OSCC. Knocking down of USP7 in tumor cells not only suppressed HSC3 cells proliferation, migration and invasion, but also promoted cell apoptosis. Moreover, USP7 siRNA blocked the activation of Akt/ERK signaling pathway. In conclusion, data presented here suggests that USP7 promotes the progression of OSCC. USP7 may be used as a new therapeutic target for OSCC diagnosis and treatment.

USP41 promotes breast cancer via regulating RACK1

Background

Breast cancer (BC) is the most common cancer diagnosed among women and is the second leading cause of cancer death. It is of great significance to explore potential candidate targets for BC.

Methods

The expression of ubiquitin-specific protease 41 (USP41) and its prognosis prediction function was firstly evaluated by TCGA database analysis. Using BC cell lines and specimens from 10 patients with primary BC, the upregulation of USP41 in BC was ensured. By USP41 overexpression or knockdown, its function was studied by cell function assays, small interfering RNA (siRNA), western blot, mass spectrometry, and flow cytometry. The potential mechanism of USP41 was explored via Co-Immunoprecipitation mass spectrometry, and western blot.

Results

TCGA database analysis revealed that in metastatic BC, USP41 expression was upregulated and negatively correlated with BC prognosis. In BC cancer cells and cancer specimens, USP41 was also upregulated. Overexpression of USP41 greatly enhanced BC colony-forming ability, proliferation, and migration. In contrast, USP41 knockdown significantly inhibited BC colony-forming ability, proliferation, and migration. Moreover, Co-Immunoprecipitation mass spectrometry results indicated that USP41 could interact with RACK1. USP41 promoted the protein expression of RACK1. The expression of RACK1 in BC tissues was upregulated. Knockdown of RACK1 inhibited cell growth and migration, and reversed the oncogenic function of USP41 in BC cells.

Conclusions

USP41 can be a potential therapeutic target against BC via RACK1.