Tripartite Motif Research Articles

TRIM21-mediated ubiquitination and phosphorylation of ERK1/2 promotes cell proliferation and drug resistance in pituitary adenomas.

Pituitary adenomas (PAs) are common intracranial tumors and TRIM family plays a crucial role in cell proliferation, and therapeutic resistance of tumors. However, the role of the TRIM family in PAs is not well recognized. CRISPR screening explored the role of TRIM family in the cell proliferation and drug resistance in PAs. In vitro and in vivo experiments were performed to evaluate the effects of Tripartite Motif Containing 21 (TRIM21). RNA-sequencing, mass spectrometry, immunoprecipitation and ubiquitination experiments were performed to explore the molecular mechanism. NanoBiT assays were used to screen the drugs reducing TRIM21 expression. CRISPR-Cas9 screens identified that TRIM21 facilitated cell proliferation and drug resistance in PAs. Mechanistically, TRIM21 interacted with ERK1/2 through PRY-SPRY domain, leading to ERK1/2 K27-linked ubiquitination. The ERK1/2 ubiquitination promotes the interaction between ERK1/2 and MEK1/2, thereby facilitating the phosphorylation of ERK1/2. However, an excess presence of TRIM21 supressed the phosphorylation of ERK1/2 and cell proliferation via activating ERK1/2 negative feedback pathways. Importantly, TRIM21 was upregulated in dopamine-resistant prolactinomas and cabergoline-resistant MMQ cells. Furthermore, drug screening identified that Fimepinostat and Quisinostat, can reduce the protein levels of TRIM21, inhibit tumor progression, and increase drug sensitivity. TRIM21 may represent a therapeutic target for tumors, and inhibiting TRIM21 could be a potential strategy for tumor treatment.

XAF1 antagonizes TRIM28 activity through the assembly of a ZNF313-mediated destruction complex to suppress tumor malignancy.

X-linked inhibitor of apoptosis-associated factor 1 (XAF1) is a stress-inducible pro-apoptotic protein that is commonly inactivated in multiple human cancers. Nevertheless, the molecular basis for its tumor suppression function remains largely uncharacterized. Here we report that XAF1 antagonizes the oncogenic activity of tripartite motif containing 28 (TRIM28) ubiquitin E3 ligase through zinc finger protein 313 (ZNF313)-induced ubiquitination and proteasomal degradation. XAF1 exerts apoptosis-promoting effect more strongly in TRIM28+/+ versus XAF1-/- tumor cells and suppresses tumor cell growth, migration, invasion, and epithelial-to-mesenchymal transition and xenograft tumor growth in a highly TRIM28-dependent fashion. Mechanistically, XAF1 interacts directly with the RING domains of TRIM28 and ZNF313 through the ZF6 and ZF7 domain, respectively, thereby facilitating ZNF313 interaction with and ubiquitination of TRIM28. A mutant XAF1 lacking either ZF6 or ZF7 domain exhibits no activity to promote TRIM28 ubiquitination. By destabilizing TRIM28, XAF1 blocks TRIM28-driven ubiquitination of p53 and RLIM, p53-HDAC1 interaction, and TWIST1 stabilization. Intriguingly, TRIM28 destabilizes XAF1 through K48-linked polyubiquitination and proteasomal degradation to protect tumor cells from apoptotic stress, indicating its role as an intrinsic antagonist against XAF1 and the antagonistic interplay of XAF1 and TRIM28. XAF1 expression is inversely correlated with TRIM28 expression in cancer cell lines and tumor tissues and more tightly associated with the survival of TRIM28-high versus TRIM28-low patients. Together, this study uncovers a novel mechanism by which XAF1 suppresses tumor malignancy and an important role for XAF1-TRIM28 interplay in governing stress response, illuminating the mechanistic consequence of its alteration during tumorigenic process.

Replenishing co-downregulated miR-100-5p and miR-125b-5p in malignant germ cell tumors causes growthinhibition through cell cycle disruption.

MicroRNAs (miRNAs) are short, nonprotein-coding RNAs, and their expression is dysregulated in malignant germ cell tumors (GCTs). Here, we investigated the causes and consequences of downregulated miR-99a-5p/miR-100-5p (functionally identical) and miR-125b-5p levels in malignant GCTs regardless of age, site, or subtype. Quantitative RT-PCR was used to assess miR-99a-5p/miR-100-5p, miR-125b-5p, and associated gene expression in malignant GCT tissues/cell lines [seminoma (Sem), yolk sac tumor (YST), embryonal carcinoma (EC)]. Cells were treated with demethylating 5-azacytidine and pyrosequencing was performed. Combination miR-100-5p/miR-125b-5p mimic replenishment was used to treat malignant GCTcells. Global messenger RNA (mRNA) targets of the replenished miRNAs were identified and Metascape used to study pathway effects. We found that expression levels of miR-99a-5p/miR-100-5p and miR-125b-5p, their respective pri-miRNAs, and associated genes from chromosomes 11 and 21 (chr11/chr21) were downregulated and highly correlated in malignant GCTcells. Treatment with 5-azacytidine caused upregulation of these miRNAs, with pyrosequencing revealing hypermethylation of their chr11/chr21 loci, likely contributing to miR-100-5p/miR-125b-5p downregulation. Combination miR-100-5p/miR-125b-5p mimic replenishment resulted in growth inhibition in Sem/YST cells, with miR-100-5p/miR-125b-5p mRNA targets enriched in downregulated genes, which were involved in cell cycle (confirmed by flow cytometry) and signaling pathways. Knockdown of the miR-100-5p/miR-125b-5p target tripartite motif containing 71 (TRIM71kd) recapitulated miR-100-5p/miR-125b-5p replenishment, with growth inhibition and cell cycle disruption of Sem/YST/EC cells. Further, replenishment led to reduced lin-28 homolog A (LIN28A) levels and concomitant increases in let-7 (MIRLET7B) tumor suppressor miRNAs, creating a sustained reversion of cell phenotype. In summary, combination miR-100-5p/miR-125b-5p mimic replenishment or TRIM71kd caused growth inhibition in malignant GCTcells via cell cycle disruption. Further studies are now warranted, including mimic treatment alongside conventional platinum-based chemotherapy.

Diagnostic value of TRIM22 in diabetic kidney disease and its mechanism.

Diabetic kidney disease (DKD) is the primary reason of chronic kidney disease. Our objective was to discover potential autophagy-related biomarkers of tubulointerstitial injury in DKD and assess their clinical value. We retrieved four datasets (GSE104954, GSE30122, GSE30529, and GSE99340) of renal tubule samples from Gene Expression Omnibus (GEO) and used two algorithms (LASSO and SVM-RFE) to screen for autophagy-related differentially expressed genes (ARDEGs) in DKD. Tripartite motif containing 22 (TRIM22) was identified for subsequent validation. Validation of TRIM22 and autophagic indicators expression in clinical samples and HK-2 cells stimulated by high glucose using immunohistochemistry, immunofluorescence, and western blot. We identified four ARDEGs (TRIM22, PLK2, HTR2B, and FAS) using a diagnostic gene model. ROC curves further confirmed that TRIM22 had the best diagnostic efficacy for DKD. Both clinical samples and HK-2 cells stimulated by high glucose showed high protein expression of TRIM22. The correlation analysis revealed that TRIM22 correlates with SQSTM1, NGAL, and some clinical and pathological indicators in patients with DKD. We identified TRIM22 as a potential diagnostic biomarker for DKD, revealing its high diagnostic value in patients with DKD with moderate-to-severe interstitial fibrosis and tubular atrophy (IFTA). TRIM22 is involved in tubulointerstitial injury and autophagy dysregulation in DKD.

TRIM Proteins: Key Regulators of Immunity to Herpesvirus Infection

Herpesviruses are ubiquitous DNA viruses that can establish latency and cause a range of mild to life-threatening diseases in humans. Upon infection, herpesviruses trigger the activation of several host antiviral defense programs that play critical roles in curbing virus replication and dissemination. Recent work from many groups has integrated our understanding of TRIM (tripartite motif) proteins, a specific group of E3 ligase enzymes, as pivotal orchestrators of mammalian antiviral immunity. In this review, we summarize recent advances in the modulation of innate immune signaling by TRIM proteins during herpesvirus infection, with a focus on the detection of herpes simplex virus type 1 (HSV-1, a prototype herpesvirus) by cGAS-STING, RIG-I-like receptors, and Toll-like receptors. We also review the latest progress in understanding the intricate relationship between herpesvirus replication and TRIM protein-regulated autophagy and apoptosis. Finally, we discuss the maneuvers used by HSV-1 and other herpesviruses to overcome TRIM protein-mediated virus restriction.

The Regulation of Innate Antiviral Immunity by TRIM56

Abstract A member of the tripartite-motif (TRIM) protein family of E3 ligases, TRIM56 has increasingly been recognized as a versatile player in innate antiviral immunity that operates via catalytically-dependent and catalytically-independent mechanisms. Herein, we provide a concise overview of the various roles that TRIM56 has been demonstrated to play in host interactions with viruses, including its "direct" virus-restricting activities and "indirect" antiviral effects resulting from its positive regulation of innate immune signaling. In addition, we discuss the current understanding of the molecular determinants and underlying biology by which TRIM56 functions in these processes.

Multifaceted role of TRIM28 in health and disease.

The TRIM (tripartite motif) family, with TRIM28 as a key member, plays a vital role in regulating health and disease. TRIM28 contains various functional domains essential for transcriptional regulation, primarily through its interaction with KRAB-ZNF proteins, which influence chromatin remodeling and gene expression. Despite extensive research, the precise mechanisms by which TRIM28 impacts health and disease remain elusive. This review delves into TRIM28's multifaceted roles in maintaining health, contributing to a variety of diseases, and influencing cancer progression. In cancers, TRIM28 exhibits a dual nature, functioning as both a tumor promoter and suppressor depending on the cellular context and cancer type. The review also explores its critical involvement in processes such as DNA repair, cell cycle regulation, epithelial-to-mesenchymal transition, and the maintenance of stem cell properties. By uncovering TRIM28's complex roles across different cancers and other diseases, this review underscores its potential as a therapeutic target. The significance of TRIM28 as a versatile regulator opens the door to innovative therapeutic strategies, particularly in cancer treatment and the management of other diseases. Ongoing research into TRIM28 may yield key insights into disease progression and novel treatment options.

Tripartite motif 22 interacts with protein phosphatase magnesium-dependent 1 A to aggravate radiation-induced epithelial-mesenchymal transition and fibrogenesis in lung epithelial cells

Tripartite motif 22 interacts with protein phosphatase magnesium-dependent 1 A to aggravate radiation-induced epithelial-mesenchymal transition and fibrogenesis in lung epithelial cells

Tripartite motif 25 inhibits protein aggregate degradation during PRRSV infection by suppressing p62-mediated autophagy.

Viral infection causes endoplasmic reticulum stress and protein metabolism disorder, influencing protein aggregates formation or degradation that originate from misfolded proteins. The mechanism by which host proteins are involved in the above process remains largely unknown. The present study found that porcine reproductive and respiratory syndrome virus (PRRSV) infection promoted the degradation of intracellular ubiquitinated protein aggregates via activating autophagy. The host cell E3 ligase tripartite motif-containing (TRIM)25 promoted the recruitment and aggregation of polyubiquitinated proteins and impeded their degradation caused by PRRSV. TRIM25 interacted with ubiquitinated aggregates and was part of the aggregates complex. Next, the present study investigated the mechanisms by which TRIM25 inhibited the degradation of protein aggregates, and it was found that TRIM25 interacted with both Kelch-like ECH-associated protein 1 (KEAP1) and nuclear factor E2-related factor 2 (Nrf2), facilitated the nuclear translocation of Nrf2 by targeting KEAP1 for K48-linked ubiquitination and proteasome degradation, and activated Nrf2-mediated p62 expression. Further studies indicated that TRIM25 interacted with p62 and promoted its K63-linked ubiquitination via its E3 ligase activity and thus caused impairment of its oligomerization, aggregation, and recruitment for the autophagic protein LC3, leading to the suppression of autophagy activation. Besides, TRIM25 also suppressed the p62-mediated recruitment of ubiquitinated aggregates. Activation of autophagy decreased the accumulation of protein aggregates caused by TRIM25 overexpression, and inhibition of autophagy decreased the degradation of protein aggregates caused by TRIM25 knockdown. The current results also showed that TRIM25 inhibited PRRSV replication by inhibiting the KEAP1-Nrf2-p62 axis-mediated autophagy. Taken together, the present findings showed that the PRRSV replication restriction factor TRIM25 inhibited the degradation of ubiquitinated protein aggregates during viral infection by suppressing p62-mediated autophagy.IMPORTANCESequestration of protein aggregates and their subsequent degradation prevents proteostasis imbalance and cytotoxicity. The mechanisms controlling the turnover of protein aggregates during viral infection are mostly unknown. The present study found that porcine reproductive and respiratory syndrome virus (PRRSV) infection promoted the autophagic degradation of ubiquitinated protein aggregates, whereas tripartite motif-containing (TRIM)25 reversed this process. It was also found that TRIM25 promoted the expression of p62 by activating the Kelch-like ECH-associated protein 1 (KEAP1) and nuclear factor E2-related factor 2 (Nrf2) pathway and simultaneously prevented the oligomerization of p62 by promoting its K63-linked ubiquitination, thus suppressing its recruitment of the autophagic adaptor protein LC3 and ubiquitinated aggregates, leading to the inhibition of PRRSV-induced autophagy activation and the autophagic degradation of protein aggregates. The present study identified a new mechanism of protein aggregate turnover during viral infection and provided new insights for understanding the pathogenic mechanism of PRRSV.

Mechanism of lactic acidemia-promoted pulmonary endothelial cells death in sepsis: role for CIRP-ZBP1-PANoptosis pathway

BackgroundSepsis is often accompanied by lactic acidemia and acute lung injury (ALI). Clinical studies have established that high serum lactate levels are associated with increased mortality rates in septic patients. We further observed a significant correlation between the levels of cold-inducible RNA-binding protein (CIRP) in plasma and bronchoalveolar lavage fluid (BALF), as well as lactate levels, and the severity of post-sepsis ALI. The underlying mechanism, however, remains elusive.MethodsC57BL/6 wild type (WT), Casp8−/−, Ripk3−/−, and Zbp1−/− mice were subjected to the cecal ligation and puncture (CLP) sepsis model. In this model, we measured intra-macrophage CIRP lactylation and the subsequent release of CIRP. We also tracked the internalization of extracellular CIRP (eCIRP) in pulmonary vascular endothelial cells (PVECs) and its interaction with Z-DNA binding protein 1 (ZBP1). Furthermore, we monitored changes in ZBP1 levels in PVECs and the consequent activation of cell death pathways.ResultsIn the current study, we demonstrate that lactate, accumulating during sepsis, promotes the lactylation of CIRP in macrophages, leading to the release of CIRP. Once eCIRP is internalized by PVEC through a Toll-like receptor 4 (TLR4)-mediated endocytosis pathway, it competitively binds to ZBP1 and effectively blocks the interaction between ZBP1 and tripartite motif containing 32 (TRIM32), an E3 ubiquitin ligase targeting ZBP1 for proteasomal degradation. This interference mechanism stabilizes ZBP1, thereby enhancing ZBP1-receptor-interacting protein kinase 3 (RIPK3)-dependent PVEC PANoptosis, a form of cell death involving the simultaneous activation of multiple cell death pathways, thereby exacerbating ALI.ConclusionsThese findings unveil a novel pathway by which lactic acidemia promotes macrophage-derived eCIRP release, which, in turn, mediates ZBP1-dependent PVEC PANoptosis in sepsis-induced ALI. This finding offers new insights into the molecular mechanisms driving sepsis-related pulmonary complications and provides potential new therapeutic strategies.

Nap1L1 Ubiquitination Degradation-dependent Protective Effects of Wnt2 on Cardiac Ischemia/Reperfusion Injury

Abstract Background Cardiomyocyte death during ischemia/reperfusion (I/R) injury occurs following the restoration of blood flow for obstructed coronary arteries, posing a challenge to timely reperfusion strategy for ischemic heart disease. This study aimed to investigate the potential protective role of Wnt2 against cardiomyocyte death after I/R injury. Methods Serum Wnt2 levels in patients with acute myocardial infarction (AMI) before and after percutaneous coronary intervention (PCI) and in mice subjected to I/R were measured by ELISA. Cardiomyocyte death, including apoptosis and ferroptosis, which were examined by TUNEL and thiobarbituric acid reactive substances (TBARs) assay, respectively. TMT6-based proteomics analysis was used to identify critical molecules mediating the effects of Wnt2. Results Serum Wnt2 level decreased after PCI in patients with MI and was negatively correlated with cTNT and CK-MB levels within the first 48 hours post-PCI. Wnt2 also decreased in I/R mice in compared with sham group.Supplement of rbWnt2 ameliorated I/R injury as characterized by the improved cardiac function and decreased infarct area and level of asynchronicity. Proteomics analysis KEGG Enrichment top 20 of differentially expressed proteins (DEPs) included reactive oxygen species (ROS). RbWnt2 inhibited cardiomyocytes apoptosis and ferroptosis by suppressed ROS level following I/R in vivo and in vitro. Based on proteomics analysis data, most of differentially expressed proteins (DEGs) were enriched in cytoplasm or nucleus. Among them, Nucleosome assembly protein-like 1(Nap1L1) was progressively increased in hearts following I/R, and showed a negative correlation with cardiac Wnt2 level during the I/R procedure. RbWnt2 treatment significantly attenuated the upregulation of Nap1L1 induced by I/R injury in vivo and in vitro. Hypoxia/Normoxia injury elicited Nap1L1 increased both in nucleus and cytoplasm, which was attenuated by rbWnt2 treatment in AMCMs. AAV9 mediated knockdown of Nap1l1 protects heart from apoptosis and ferroptosis while overexpression of Nap1l1 partly abolished the protective effects of Wnt2 in I/R mice. Mechanistically, Wnt2 upregulated anti-oxidative enzymes (Gpx1, Gpx4, Ucp3, Sod1, Sod2) by regulation of Nap1l1 to suppress ROS level and protect cardiomycoytes following I/R injury. Further analysis revealed that binding of Wnt2 and Lrp6 enhanced the expression of Tripartite motif 11 (TRIM11, a ubiquitin E3 ligase) and subsequently promoted the degradation of Nap1l1 in cardiomyocytes, which contributes to cardiac protection following I/R injury. Conclusions Wnt2 protects the heart against I/R-induced injury by inducing Nap1L1 degradation through Lrp6/Trim11 signaling, which was mediated by suppressing ROS levels via enhancing anti-oxidation enzymes to inhibits cardiomyocytes apoptosis and ferroptosis. These findings may offer new insights for developing therapeutic strategies to prevent I/R injury.Abstract GraphConclusion

Targeting MuRF1 to Combat Skeletal Muscle Wasting in Cardiac Cachexia: Mechanisms and Therapeutic Prospects.

Cardiac cachexia, the terminal stage of chronic heart failure, is characterized by severe systemic metabolic imbalances and significant weight loss, primarily resulting from skeletal muscle mass depletion. Despite the detrimental consequences, there is no standardized and clinically-approved intervention currently available for cardiac cachexia. In the context of cardiac cachexia, accelerated protein turnover, that is, inhibited protein synthesis and enhanced protein degradation, plays a crucial role in skeletal muscle wasting. This process is primarily mediated by various proteins encoded by atrogenes. Among them, the atrogene Trim63 (tripartite motif family 63) and its encoded protein MuRF1 have been extensively studied. This review article aims to elucidate the pathogenic mechanisms underlying skeletal muscle wasting in cardiac cachexia, describe the biochemical characteristics of MuRF1, and provide an overview of the investigation into MuRF1-targeting inhibitors. The ultimate goal is to offer novel strategies for the clinical treatment for skeletal muscle wasting associated with cardiac cachexia.

TRIM55 restricts the progression of hepatocellular carcinoma through ubiquitin-proteasome-mediated degradation of NF90

Hepatocellular carcinoma (HCC) is a prevalent malignant tumor worldwide. Tripartite motif containing 55 (TRIM55), also known as muscle-specific ring finger 2 (Murf2), belongs to the TRIM protein family and serves as an E3 ligase. Recently, the function and mechanism of TRIM55 in the advancement of solid tumors have been elucidated. However, the role of TRIM55 and its corresponding protein substrates in HCC remains incompletely explored. In this study, we observed a significant reduction in TRIM55 expression in HCC tissues. The downregulation of TRIM55 expression correlated with larger tumor size and elevated serum alpha-fetoprotein (AFP), and predicted unfavorable overall and tumor-free survival. Functional experiments demonstrated that TRIM55 suppressed the proliferation, migration, and invasion of HCC cells in vitro, as well as hindered HCC growth and metastasis in vivo. Additionally, TRIM55 exhibited a suppressive effect on HCC angiogenesis. Mechanistically, TRIM55 interacted with nuclear factor 90 (NF90), a double-stranded RNA-binding protein responsible for regulating mRNA stability and gene transcription, thereby facilitating its degradation via the ubiquitin-proteasome pathway. Furthermore, TRIM55 attenuated the association between NF90 and the mRNA of HIF1α and TGF-β2, consequently reducing their stability and inactivating the HIF1α/VEGF and TGFβ/Smad signaling pathways. In conclusion, our findings unveil the important roles of TRIM55 in suppressing the progression of HCC partly by promoting the degradation of NF90 and subsequently modulating its downstream pathways, including HIF1α/VEGF and TGFβ/Smad signaling.

Targeting suppression of AKT activation boosts chemosensitivity of hepatocarcinoma cells via regulation of inflammation and metastasis: Functional protection of Rehmapicroside

Hepatocellular carcinoma (HCC) is the most common malignant tumors with poor prognosis and few effective therapeutic strategies. Although cisplatin (cDDP) is the first-line chemotherapy for HCC, its application has been limited due to drug resistance and side effects. Rehmapicroside (Reh) is a major active principle of the root of Radix Rehmanniae that has anti-tumor effects. In the present study, we uncovered the role of Reh in modulating chemosensitivity of cDDP in HCC. We found that combinational treatments of Reh and cDDP significantly reduced the cell proliferation of HCC cells at relatively lower concentrations for each drug. Cell cycle arrest in G2/M phase was markedly induced in HCC cells co-treated with Reh and cDDP compared with cDDP alone group. In addition, Reh dramatically enhanced the capacity of cDDP to induce apoptosis in HCC cells through increasing Caspase-3 cleavage. Co-treatment with Reh and cDDP effectively suppressed tumor growth in xenograft mouse models of HCC without adverse effects. Moreover, migration and invasion of HCC cells were significantly restrained by combinational treatments of Reh and cDDP. Mechanistically, tripartite motif protein 21-phosphatidylinositol 3-kinase/protein kinase B (TRIM21-PI3K/AKT) signaling pathway was considerably impeded in HCC cells and tumor tissues by Reh and cDDPco-treatment. Notably, we found that constitutive activation of AKT almost completely abrogated the capacity of Reh plus cDDP to inhibit cell proliferation, migration, and invasion. Collectively, our results demonstrated that combinational therapy of Reh and cDDP may be a novel and effective therapeutic strategy for HCC treatment.

NPRL2 promotes TRIM16-mediated ubiquitination degradation of Galectin-3 to prevent CD8+T lymphocyte cuproptosis in glioma

BackgroundOur previous study found that tumor suppressor nitrogen permease regulator like-2(NPRL2) is frequently downregulated in glioma, leading to malignant growth. However, NPRL2-mediated crosstalk between tumor cells and immune cells remains unclear.MethodsThe regulatory effects of NPRL2 on tripartite motif–containing protein 16(TRIM16) dependent ubiquitination degradation of Galectin-3(Gal-3) were explored. The effects of Gal-3 on copper uptake, immunocompetence and cuproptosis were investigated in CD8+T lymphocytes(CD8+T cells). The ability of NPRL2 to protect CD8+T cells from Gal-3 damage was evaluated. Furthermore, the correlations among NPRL2, TRIM16, Gal-3 and CD8+T cell accumulation were analyzed in glioma clinical specimens.ResultsNPRL2 increased the TRIM16 expression via inactivation of ERK1/2, which in turn promoted the ubiquitination-mediated degradation of Gal-3 and diminished Gal-3 release from glioma cells. Moreover, Gal-3 accelerated copper uptake and triggered cuproptosis in CD8+T cells, whereas NPRL2 increased CD8+T cell recruitment and prevented impairment of CD8+T cells by Gal-3. Clinical samples revealed that NPRL2 expression was positively associated with TRIM16 expression and negatively correlated with Gal-3, but Gal-3 expression was negatively associated with CD8+T cell accumulation.ConclusionGlioma-derived NPRL2/TRIM16/Gal-3 axis participates in the regulation of CD8+T cell cuproptosis, which provides a promising strategy to rescue the immune activity of CD8+T cells and reverse immunosuppression in glioma.

Fangchinoline suppresses hepatocellular carcinoma by regulating ROS accumulation via the TRIM7/Nrf2 signaling pathway

BackgroundDysregulation of redox homeostasis is associated with developing hepatocellular carcinoma (HCC). Oxidative stress (OS) is distinguished by the accumulation of ROS, which plays a variety of roles in cancer pathology. Fangchinoline (FAN), a bis-benzylisoquinoline alkaloid, has anti-cancer pharmacological activity. However, the regulatory mechanism of FAN on OS and whether it can inhibit HCC by mediating OS are still unclear. Hypothesis/PurposeThis paper aims to explore the effectiveness of FAN in preventing HCC via regulating OS and identify the underlying molecular mechanisms. MethodsWe used the primary HCC mouse model and hepatoma cell line to explore the suppressive effect of FAN on hepatocarcinogenesis. To study the role of ROS in the anti-hepatocarcinoma effect of FAN in cell model and mouse model. The mechanism of FAN-induced nuclear factor erythroid 2-related factor 2 (Nrf2) pathway activation was studied through various techniques, including generation of Nrf2 and tripartite motif containing 7 (TRIM7) gene overexpressing or knockdown cell model, co-immunoprecipitation, immunohistochemistry and subcutaneous tumor xenograft models constructed by the stable TRIM7-overexpression HLE cells, etc. ResultsWe showed that FAN significantly inhibited cell proliferation and hepatocarcinogenesis in HCC cells and primary HCC mouse model. The FAN-induced mitochondrial dysfunction promoted ROS accumulation, and using N-Acetylcysteine to clear ROS reversed the anti-HCC effects of FAN. We observed that FAN is capable of activating the Nrf2 pathway. This effect was thought to be due to the fact that, in response to the FAN-induced OS, the cancer cells created a feedback loop to stable Nrf2 via depressing the K48-linkage ubiquitination of it, which was caused by reduced binding of kelch-like ECH-associated protein 1 (Keap1) and Nrf2 and elevated TRIM7 expression. Indeed, overexpression of TRIM7 suppressed the anti-hepatocarcinoma effect of FAN. ConclusionThe study determines the anti-liver cancer effect of FAN and first describes the positive regulatory effect of TRIM7 on Nrf2 signaling. We reveal that TRIM7/Nrf2 signaling served as a target of FAN-induced ROS accumulation in HCC, which helps to clarify the mechanism of action of FAN against HCC and provides a theoretical basis for FAN as an anti-cancer drug.

Opposing regulation of the STING pathway in hepatic stellate cells by NBR1 and p62 determines the progression of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) emerges from chronic inflammation, to which activation of hepatic stellate cells (HSCs) contributes by shaping a pro-tumorigenic microenvironment. Key to this process is p62, whose inactivation leads to enhanced hepatocarcinogenesis. Here, we show that p62 activates the interferon (IFN) cascade by promoting STING ubiquitination by tripartite motif protein 32 (TRIM32) in HSCs. p62, binding neighbor of BRCA1 gene 1 (NBR1) and STING, triggers the IFN cascade by displacing NBR1, which normally prevents the interaction of TRIM32 with STING and its subsequent activation. Furthermore, NBR1 also antagonizes STING by promoting its trafficking to the endosome-lysosomal compartment for degradation independent of autophagy. Of functional relevance, NBR1 deletion completely reverts the tumor-promoting function of p62-deficient HSCs by rescuing the inhibited STING-IFN pathway, thus enhancing anti-tumor responses mediated by CD8+ Tcells. Therefore, NBR1 emerges as a synthetic vulnerability of p62 deficiency in HSCs by promoting the STING/IFN pathway, which boosts anti-tumor CD8+ Tcell responses to restrain HCC progression.

Extracellular vesicle transfer of miR-1 to adipose tissue modifies lipolytic pathways following resistance exercise.

Extracellular vesicles (EVs) have emerged as important mediators of inter-tissue signaling and exercise adaptations. In this human study (n = 32), we provide evidence that muscle-specific microRNA-1 (miR-1) was transferred to adipose tissue via EVs following an acute bout of resistance exercise. Using a multi-model machine learning automation tool, we discovered muscle primary miR-1 transcript and CD63+ EV count in circulation as top explanatory features for changes in adipose miR-1 levels in response to resistance exercise. RNA-sequencing (RNA-seq) and in-silico prediction of miR-1 target genes identified caveolin 2 (CAV2) and tripartite motif containing 6 (TRIM6) as miR-1 target genes downregulated in the adipose tissue of a subset of participants with the highest increases in miR-1 levels following resistance exercise (n = 6). Overexpression of miR-1 in differentiated human adipocyte-derived stem cells downregulated these miR-1 targets and enhanced catecholamine-induced lipolysis. These data identify a potential EV-mediated mechanism by which skeletal muscle communicates to adipose tissue and modulates lipolysis via miR-1.

TRIM35 triggers cardiac remodeling by regulating SLC7A5-mediated amino acid transport and mTORC1 activation in fibroblasts

BackgroundCardiac maladaptive remodeling is one of the leading causes of heart failure with highly complicated pathogeneses. The E3 ligase tripartite motif containing 35 (TRIM35) has been identified as a crucial regulator governing cellular growth, immune responses, and metabolism. Nonetheless, the role of TRIM35 in fibroblasts in cardiac remodeling remains elusive.MethodsHeart tissues from human donors were used to verify tissue-specific expression of TRIM35. Fibroblast-specific Trim35 gene knockout mice (Trim35cKO) were used to investigate the function of TRIM35 in fibroblasts. Cardiac function, morphology, and molecular changes in the heart tissues were analyzed after transverse aortic constriction (TAC) surgery. The mechanisms by which TRIM35 regulates fibroblast phenotypes were elucidated using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and RNA sequencing (RNA-Seq). These findings were further validated through the use of adenoviral and adeno-associated viral transfection systems, as well as the mTORC1 inhibitor Rapamycin.ResultsTRIM35 expression is primarily up-regulated in cardiac fibroblasts in both murine and human fibrotic hearts, and responds to TGF-β1 stimulation. Specific deletion of TRIM35 in cardiac fibroblasts significantly improves cardiac fibrosis and hypertrophy. Consistently, the overexpression of TRIM35 promotes fibroblast proliferation, migration, and differentiation. Through paracrine signaling, it induces hypertrophic growth of cardiomyocytes. Mechanistically, we found that TRIM35 interacts with, ubiquitinates, and up-regulates the amino acid transporter SLC7A5, which enhances amino acid transport and activates the mTORC1 signaling pathway. Furthermore, overexpression of SLC7A5 significantly reverses the reduced cardiac fibrosis and hypertrophy caused by conditional knockout of TRIM35.ConclusionOur findings demonstrate a novel role of fibroblast-TRIM35 in cardiac remodeling and uncover the mechanism underlying SLC7A5-mediated amino acid transport and mTORC1 activation. These results provide a potential novel therapeutic target for treating cardiac remodeling.

Targeting TRIM26: Unveiling an Oncogene and Identification of Plant Metabolites as a Potential Therapeutics for Breast Cancer.

Breast cancer is the major cause of cancer-related mortality and frequent malignancies among women worldwide. The TRIM (Tripartite Motif) protein family is a broad and diverse set of proteins that contain a conserved structural motif known as the tripartite motif, which comprises of three different domains, B-box domain, Coiled-coil domain and RBR (Ring-finger, B-box, and coiled-coil) domain. TRIM proteins are involved in regulating cancer growth and metastasis. However, TRIM proteins are still unexplored in cancer cell regulation. In this study, by using a cancer database expression of all TRIM proteins was determined in breast cancer. Out of 77 TRIM genes, 16 genes were upregulated in breast cancer. Here, the upregulated TRIM26 gene's role is not yet explored in breast cancer. Indeed, TRIM26 is upregulated in 21 cancer types out of 33 cancer types. To investigate the role of TRIM26 in breast cancer, siRNA-mediated gene silencing was carried out in MCF-7 and MDA-MB 231 breast cancer cells. Reduced expression of TRIM 26 decreased cancer cell proliferation, migration and invasion with simultaneous reduction of various proliferative, cell cycle and mesenchymal markers and upregulation of epithelial markers. Further, docking studies found potential novel plant metabolites. Thus, targeting TRIM26 may provide a novel therapeutic approach for breast cancer treatment.