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Transfer RNA‐derived fragments (tRFs) represent a novel class of non‐coding RNA transcripts that possess specific biological functions. However, the involvement of tRFs in retinal microvascular diseases remains poorly understood. In this study, we aimed to reveal whether modulation of tRF‐30 expression could attenuate pathological retinal neovascular diseases. Our findings demonstrate a significant upregulation of tRF‐30 expression levels in both in vivo models of diabetic retinopathy (DR) and in vitro endothelial sprouting models. Conversely, inhibition of tRF‐30 expression suppressed the formation of abnormal neovascularization in the retina in vivo, while reducing the proliferation and migration activity of retinal vascular endothelial cells in vitro. We also found that tRF‐30 modulates retinal neovascularization through the tRF‐30/TRIB3/signal transducer and activated transcription 3 signaling pathway. Furthermore, we validated a significant upregulation of tRF‐30 expression levels in the vitreous humor of DR patients, with high levels of both validity and specificity in diagnostic testing. Collectively, our findings highlight a pro‐angiogenic role for tRF‐30 in DR. Intervening in the tRF‐30 signaling pathway may represent a promising prevention and treatment strategy for retinal angiogenesis. [ABSTRACT FROM AUTHOR]

As one of the most commonly used antidiabetic medications clinically, liraglutide is involved in the protection of vascular endothelium, and whether it can relieve high glucose-induced vascular endothelial damage was unknown. This study aims to address the response of liraglutide (LIRA) on human umbilical vein endothelial cells, as well as to elucidate its possible underlying mechanism. We established a vascular endothelial cell injury model by exposing human umbilical vein endothelial cells (HUVECs) to high glucose, and used LIRA pretreatment before HG treatment to address the endothelial protective effect of LIRA. Our results suggest that LIRA prevented HG-induced HUVEC apoptosis, oxidative stress, inflammasome activation, and pyroptosis. Furthermore, silencing of tribbles homolog 3 (TRIB3) could markedly reduce HG-induced HUVEC apoptosis, ROS level, the expressions of TXNIP, cleaved caspase3, NLRP3, and caspase1, indicating TRIB3 inhibition protected HUVECs against HG-induced vascular endothelial injury. In addition, LIRA restrained NF-κB/IκB-α signaling pathway activation in HUVECs. Thus, LIRA appears to mitigate HG-induced apoptosis, oxidative stress, inflammasome activation, and pyroptosis in HUVECs via regulating the TRIB3/NF-κB/IκB-α signaling pathway. Our study provides new insight into the mechanisms underlying the protective activity of LIRA against the vascular endothelial injury in diabetic vascular complication. [ABSTRACT FROM AUTHOR]

Enterovirus A71 (EV-A71) is the main pathogen causing hand, foot and mouth disease (HFMD) in children and occasionally associated with neurological diseases such as aseptic meningitis, brainstem encephalitis (BE) and acute flaccid paralysis. We report here that cellular pseudokinase tribbles 3 (TRIB3) facilitates the infection of EV-A71 via dual mechanisms. In one hand, TRIB3 maintains the metabolic stability of scavenger receptor class B member 2 (SCARB2), the bona fide receptor of EV-A71, to enhance the infectious entry and spreading of the virus. On the other hand, TRIB3 facilitates the replication of EV-A71 RNA in a SCARB2-independent manner. The critical role of TRIB3 in EV-A71 infection and pathogenesis was further demonstrated in vivo in mice. In comparison to wild-type C57BL/6 mice, EV-A71 infection in TRIB3 knockdown mice (Trib3+/−) resulted in significantly lower viral loads in muscular tissues and reduced lethality and severity of clinical scores and tissue pathology. In addition, TRIB3 also promoted the replication of coxsackievirus B3 (CVB3) and coxsackievirus A16 (CVA16) in vitro. In conclusion, our results suggest that TRIB3 is one of key host cellular proteins required for the infection and pathogenesis of EV-A71 and some other human enteroviruses and may thus be a potential therapeutic target for combating the infection of those viruses.

Objectives: High‐grade gliomas (HGGs) are highly malignant, aggressive, and have a high incidence and mortality rate. The aim of this study was to investigate survival outcomes and prognostic factors in patients with HGGs. Methods: In this retrospective study, a total of 159 patients with histologically confirmed HGGs were included. The recruitment period was from January 2011 to December 2019. We evaluated patient demographic data, tumor characteristics, treatment methods, immunocytochemistry results, overall survival (OS) time, and progression‐free survival (PFS) time using Kaplan–<>Meier survival analysis with log‐rank testing. Additionally, we employed Cox regression analysis to identify independent factors associated with survival outcomes. Results: Kaplan–Meier survival analysis revealed that the 1‐, 2‐, and 5‐years OS rates were 81.8%, 50.3%, and 12.6%, respectively. Similarly, the 1‐, 2‐, and 5‐years PFS rates were 50.9%, 22.4%, and 3.1%, respectively. The median OS duration was 35.0 months. The univariate analysis indicated that postoperative pathological classification, grade, and age were significantly associated with patient outcomes (p < 0.01). Among the patients, 147 received concurrent chemoradiotherapy, while 12 did not. The immunohistochemical markers of ki‐67, MGMT, IDH1R132H, and p53 demonstrated statistically significant differences in their prognostic impact (p = 0.001, p = 0.020, p = 0.003, and p = 0.021, respectively). In conclusion, we found that grades, age, pathological classification, ki‐67, MGMT, and IDH1R132H expression were statistically significantly associated with PFS (p < 0.01, p = 0.004, p = 0.003, p = 0.001, p = 0.036, and p = 0.028). Additionally, immunohistochemical expressions of TRIB3 and AURKA were significantly higher in patients with shorter survival (p = 0.015 and p = 0.023). Conclusions: Tumor grade and the use of concurrent chemoradiotherapy after surgery were independent prognostic factors that significantly influenced patient survival. Additionally, tumor grade and MGMT expression were found to be independent factors affecting progression‐free survival (PFS). Notably, the expression of TRIB3 and AURKA was higher in patients with poor survival outcomes. [ABSTRACT FROM AUTHOR]

Abstract Rhabdomyosarcoma (RMS), such as other childhood tumors, has witnessed treatment advancements in recent years. However, high-risk patients continue to face poor survival rates, often attributed to the presence of the PAX3/7-FOXO1 fusion proteins, which has been associated with metastasis and treatment resistance. Despite efforts to directly target these chimeric proteins, clinical success remains elusive. In this study, the main aim was to address this challenge by investigating regulators of FOXO1. Specifically, we focused on TRIB3, a potential regulator of the fusion protein in RMS. Our findings revealed a prominent TRIB3 expression in RMS tumors, highlighting its correlation with the presence of fusion protein. By conducting TRIB3 genetic inhibition experiments, we observed an impairment on cell proliferation. Notably, the knockdown of TRIB3 led to a decrease in PAX3-FOXO1 and its target genes at protein level, accompanied by a reduction in the activity of the Akt signaling pathway. Additionally, inducible silencing of TRIB3 significantly delayed tumor growth and improved overall survival in vivo. Based on our analysis, we propose that TRIB3 holds therapeutic potential for treating the most aggressive subtype of RMS. The findings herein reported contribute to our understanding of the underlying molecular mechanisms driving RMS progression and provide novel insights into the potential use of TRIB3 as a therapeutic intervention for high-risk RMS patients.

Recent studies have indicated that dysregulation of the Hippo/Yes‐associated protein (YAP) axis is associated with tumor progression and therapy resistance in various cancer types, including lung adenocarcinoma (LUAD). Understanding the regulation of Hippo signaling in LUAD is of great significance. Elevated levels of TRIB3, a pseudo kinase, have been observed in certain lung malignancies and are associated with an unfavorable prognosis. Our research aims to investigate whether increased TRIB3 levels enhance the malignant characteristics of LUAD cells and tumor progression through its interaction with the Hippo signaling pathway. In this study, we reported a positive correlation between elevated expression of TRIB3 and LUAD progression. Additionally, TRIB3 has the ability to enhance TEAD luciferase function and suppress Hippo pathway activity. Moreover, TRIB3 increases total YAP protein levels and promotes YAP nuclear localization. Mechanistic experiments revealed that TRIB3 directly interacts with large tumor suppressor kinase 1 (LATS1), thereby suppressing Hippo signaling. Moreover, the decrease in METTL3‐mediated N6‐methyladenosine modification of TRIB3 results in a substantial elevation of its expression levels in LUAD cells. Collectively, our research unveils a novel discovery that TRIB3 enhances the growth and invasion of LUAD cells by interacting with LATS1 and inhibiting the Hippo signaling pathway. TRIB3 may serve as a potential biomarker for an unfavorable prognosis and a target for novel treatments in YAP‐driven lung cancer. [ABSTRACT FROM AUTHOR]

Inherited retinal degeneration (RD) constitutes a heterogeneous group of genetic retinal degenerative disorders. The molecular mechanisms underlying RD encompass a diverse spectrum of cellular signaling, with the unfolded protein response (UPR) identified as a common signaling pathway chronically activated in degenerating retinas. TRIB3 has been recognized as a key mediator of the PERK UPR arm, influencing various metabolic pathways, such as insulin signaling, lipid metabolism, and glucose homeostasis, by acting as an AKT pseudokinase that prevents the activation of the AKT → mTOR axis. This study aimed to develop a gene-independent approach targeting the UPR TRIB3 mediator previously tested by our group using a genetic approach in mice with RD. The goal was to validate a therapeutic approach targeting TRIB3 interactomes through the pharmacological targeting of EGFR-TRIB3 and delivering cell-penetrating peptides targeting TRIB3 → AKT. The study employed rd10 and P23H RHO mice, with afatinib treatment conducted in p15 rd10 mice through daily intraperitoneal injections. P15 P23H RHO mice received intraocular injections of cell-penetrating peptides twice at a 2-week interval. Our study revealed that both strategies successfully targeted TRIB3 interactomes, leading to an improvement in scotopic A- and B-wave ERG recordings. Additionally, the afatinib-treated mice manifested enhanced photopic ERG amplitudes accompanied by a delay in photoreceptor cell loss. The treated rd10 retinas also showed increased PDE6β and RHO staining, along with an elevation in total PDE activity in the retinas. Consequently, our study demonstrated the feasibility of a gene-independent strategy to target common signaling in degenerating retinas by employing a TRIB3-based therapeutic approach that delays retinal function and photoreceptor cell loss in two RD models. [ABSTRACT FROM AUTHOR]

Rhabdomyosarcoma (RMS), such as other childhood tumors, has witnessed treatment advancements in recent years. However, high-risk patients continue to face poor survival rates, often attributed to the presence of the PAX3/7-FOXO1 fusion proteins, which has been associated with metastasis and treatment resistance. Despite efforts to directly target these chimeric proteins, clinical success remains elusive. In this study, the main aim was to address this challenge by investigating regulators of FOXO1. Specifically, we focused on TRIB3, a potential regulator of the fusion protein in RMS. Our findings revealed a prominent TRIB3 expression in RMS tumors, highlighting its correlation with the presence of fusion protein. By conducting TRIB3 genetic inhibition experiments, we observed an impairment on cell proliferation. Notably, the knockdown of TRIB3 led to a decrease in PAX3-FOXO1 and its target genes at protein level, accompanied by a reduction in the activity of the Akt signaling pathway. Additionally, inducible silencing of TRIB3 significantly delayed tumor growth and improved overall survival in vivo. Based on our analysis, we propose that TRIB3 holds therapeutic potential for treating the most aggressive subtype of RMS. The findings herein reported contribute to our understanding of the underlying molecular mechanisms driving RMS progression and provide novel insights into the potential use of TRIB3 as a therapeutic intervention for high-risk RMS patients. [ABSTRACT FROM AUTHOR]

Despite intensive studies for decades, the common mechanistic correlations among the underlying pathology of diabetes mellitus (DM), its complications, and effective clinical treatments remain poorly characterized. High-quality diets and nutrition therapy have played an indispensable role in the management of DM. More importantly, tribbles homolog 3 (TRIB3), a nutrient-sensing and glucose-responsive regulator, might be an important stress-regulatory switch, linking glucose homeostasis and insulin resistance. Therefore, this review aimed to introduce the latest research progress on the crosstalk between dietary nutrition intervention and TRIB3 in the development and treatment of DM. This study also summarized the possible mechanisms involved in the signaling pathways of TRIB3 action in DM, in order to gain an in-depth understanding of dietary nutrition intervention and TRIB3 in the pathogenesis of DM at the organism level. [ABSTRACT FROM AUTHOR]

Background: Tribbles Homolog 3 (TRIB3) is a member of the pseudokinase family of tribbles and acts as an adaptor protein to regulate different cellular processes. Upregulation of TRIB3 expression was shown either as a favorable or an adverse prognostic factor in various adult malignancies. However, TRIB3 expression has not been examined in pediatric cancers. Neuroblastoma is the most common malignant solid tumor of childhood, which affects mostly children under 5 years old. Risk stratification of patients defined by International Neuroblastoma Risk Group was used to determine prognosis and treatment of the disease. This study aimed to examine the relationship between TRIB3 protein expression levels and clinicopathological features and survival of patients. Methods: TRIB3 protein expression was analyzed using immunohistochemical staining on formalin-fixed paraffin-embedded tissue samples of neuroblastoma patients (n = 56). Survival analyses were performed with Kaplan-Meier method and log-rank tests. Association between TRIB3 expression and clinicopathological characteristics were analyzed with Spearman's correlation. Results: Of the patients, 32.1% were in the low-risk group, 21.4% in the medium-risk group, and 46.4% in the high-risk group. Survival analysis was performed in the entire neuroblastoma patient group and sub-risk groups of neuroblastoma patients. In the entire patient group, there was no significant difference in overall survival (P =.202) and event-free survival (P =.172) between TRIB3-positive and -negative patients. However, when survival analyses were performed in each risk group, TRIB3 expression was significantly associated with higher overall survival (P =.034) and event-free survival (P =.032) in low-risk group neuroblastoma patients. Nevertheless, no association was found between TRIB3 expression and overall survival (P =.799) and event-free survival (P =.448) in high-risk neuroblastoma patients. Furthermore, a significant correlation was identified between 1p36 loss-of-heterozygosity and TRIB3 expression (P =.030). However, TRIB3 expression did not correlate with other clinicopathological features. Conclusion: TRIB3 expression is a potential predictive biomarker for low-risk neuroblastoma patients. [ABSTRACT FROM AUTHOR]

Objective The aim of the study is to explore the mechanism of tribbles pseudokinase 3 (TRIB3)-regulated Akt pathway in the development of preeclampsia (PE). Study Design TRIB3 expression in the placenta of PE patient was determined by quantitative reverse transcriptase polymerase chain reaction and western blotting. Then HTR-8/SVneo or JEG-3 cells were transfected and divided into Mock, Control siRNA, TRIB3 siRNA-1, and TRIB3 siRNA-2 groups. Cell proliferation, invasion, and migration were determined by MTT assay, Transwell assay, and wound healing test, while the expression of TRIB3 and Akt pathway was measured by western blotting. PE rats were treated with TRIB3 siRNA, and blood pressure, 24-hour urinary protein, as well as serum levels of sFlt-1 and vascular endothelial growth factor (VEGF) were measured. Results The placenta of PE patients presented with increased TRIB3 expression. In comparison with Mock group, the proliferation, invasion, and migration of HTR-8/SVneo and JEG-3 cells in TRIB3 siRNA-1 group and TRIB3 siRNA-2 group increased, with decreased TRIB3 expression but enhanced expression of p-Akt/Akt, MMP-2, and MMP-9. Rats in PE group showed increases in mean arterial pressure, SBP, 24-hour urinary protein, and serum sFlt-1 levels, but decreases in serum VEGF levels, fetal weight, and placental efficiency. Moreover, TRIB3 expression was upregulated, while p-Akt/Akt was downregulated in the placenta of rats in PE group. However, indicators above were significantly improved in rats treated with TRIB3 siRNA. Conclusion TRIB3 was upregulated in the PE placenta, while silencing TRIB3 activated the Akt signaling pathway to promote the invasion and migration of trophoblast both in vitro and in vivo and ameliorated the development of PE symptoms in the PE rat model. Key Points The TRIB3 expression was increased in the placenta of PE patient Silencing TRIB3 activates Akt signal pathway. Silencing TRIB3 improves the pathological process of preeclampsia rat. [ABSTRACT FROM AUTHOR]

Abstract Acute promyelocytic leukemia (APL) is highly aggressive and is frequently associated with disseminated intravascular coagulation and high early death rates. Although all-trans retinoic acid (RA) induces complete remission in a high proportion of patients with APL, there are limited treatments for APL patients with RA resistance. Here we report an atypical APL patient, with an APL-like disease that developed very slowly without anti-leukemia therapy for nearly 2 years. During that time, the patient only intermittently received anti-HBV drugs, i.e., the combination of adefovir dipivoxil (ADV) and entecavir (ETV), leading us to hypothesize that ADV and/or ETV could inhibit APL progression. Our results showed that anti-HBV drugs ADV and ETV both exhibited significantly inhibitory effects on APL cells, and ADV indicated a much greater cytotoxic effect than ETV on APL cells. We further found that ADV significantly promoted APL cell differentiation and apoptosis, thereby restraining the progression of APL. Most importantly, our study uncovered a novel mechanism of ADV prohibiting APL progression, which was mediated, at least in part, by inhibition of TRIB3 and degradation of the oncoprotein PML-RARA, therefore leading to APL cell differentiation and apoptosis. Taken together, our study demonstrated that ADV, an anti-HBV drug, had significantly inhibitory effects on APL, and provided a novel therapeutic strategy for APL patients with RA resistance.

Sunitinib resistance presents a significant challenge in the treatment of clear cell renal cell carcinoma (ccRCC). The role of TRIB3, a newly identified oncogene, in tumor drug resistance has been widely studied. However, the mechanism by which TRIB3 contributes to sunitinib resistance in ccRCC has not been previously explored. This study aimed to investigate the mechanism through which TRIB3 regulates ferroptosis to increase the susceptibility of ccRCC to sunitinib treatment. Bioinformatics analysis and experimental validation revealed that TRIB3 is significantly upregulated in ccRCC tissues and is associated with poor prognosis. Knockdown of TRIB3 using siRNA transfection inhibited the proliferation and migration of ccRCC cells and induced ferroptosis. Following sunitinib treatment, TRIB3 knockdown increased cell sensitivity to sunitinib, enhanced the suppressive impact of sunitinib, and augmented sunitinib-induced ferroptosis. This study demonstrated that TRIB3 knockdown induces ferroptosis by targeting the SLC7A11/GPX4 pathway and enhances therapeutic efficacy of sunitinib for ccRCC, providing new insights and potential strategies to overcome the challenge of sunitinib resistance in ccRCC. • TRIB3 knockdown induces ferroptosis in ccRCC cells. • TRIB3 knockdown increases the sensitivity of ccRcc cells to sunitinib. • TRIB3 knockdown increases the sensitivity of ccRcc cells to sunitinib by regulating SLC7A11/GPX4 pathway. [ABSTRACT FROM AUTHOR]

Gastric cancer is among the common solid tumors. Chemotherapy resistance is the most common issue in gastric cancer treatment. Inhibiting intracellular autophagy may be a feasible method for overcoming chemotherapy resistance. Cepharanthine (CEP), a natural small molecule extracted from the stephania cephalantha Hayata plant, has been demonstrated to significantly inhibit cancer growth and can regulate autophagy. Although CEP can significantly inhibit cancer growth, it remains unclear whether CEP can regulate autophagy in gastric cancer. This study aimed to investigate whether CEP can enhance the sensitivity of gastric cancer to chemotherapy and elucidate its molecular mechanism. Three gastric cancer cell lines (AGS, SGC7901, and MFC) and one normal gastric mucosal epithelial cell line (GES-1) were used for in vitro experiments. The characterization of autophagy in gastric cancer cells included the detection of autophagy markers and autophagy flux through immunofluorescence staining and Western blotting, as well as the assessment of lysosomal function using fluorescence staining (LysoTracker Red DND-99, Acridine Orange staining) and Western blotting. The cytotoxicity of CEP, autophagy inhibitors (chloroquine [CQ] and 3-methyladenine [3MA]), and chemotherapy drugs (doxorubicin [DOX] and cisplatin [CIS]) was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, cell colony formation, and fluorescence staining techniques (H2DCFDA, Dihydroethidium, and JC-1 staining). The interaction between CEP and autophagy inhibitors was tested in a 615 mice model, and changes in the gut microbiota were determined through accurate 16S absolute quantification sequencing. The signaling pathway and autophagy regulatory target TRIB3-FOXO3-FOXM1 were confirmed through molecular docking, RNA sequencing, bioinformatic analysis, transfection techniques, and Western blotting. CEP blocked autophagic flux in gastric cancer cells without affecting lysosomal function. As a novel autophagy inhibitor, CEP could combine with conventional autophagy inhibitors (CQ and 3MA) to block intracellular autophagy, thereby inhibiting gastric cancer growth. During this process, changes in the gut microbiota were observed, including low-level changes in Odoribacterium, Erysipelatoclostridium , and ParaPrevotella and high-level changes in Ileibacterium, Enterorhabdus , and Bifidobacterium. Additionally, CEP synergistically inhibited the growth of gastric cancer when combined with chemotherapy drugs. Mechanistically, the TRIB3-FOXO3-FOXM1 signaling axis was found to be involved in the inhibition of gastric cancer by CEP combined with autophagy inhibitors and chemotherapy drugs, thereby mediating cell apoptosis. This study links the TRIB3-FOXO3-FOXM1 axis with chemotherapy efficacy. Our findings demonstrated that CEP inhibits autophagy by modulating the FOXO3-FOXM1 axis. When combined with chemotherapy drugs (DOX and CIS), CEP, as an autophagy inhibitor, can limit TRIB3 protein expression, thereby regulating the FOXO3-FOXM1 axis and enhancing its ability to prevent gastric cancer growth. These findings may contribute to improving the prognosis of patients with gastric cancer. Furthermore, these results enrich the fundamental understanding of how autophagy inhibition can enhance clinical cancer treatment efficacy and provide insights into the potential mechanisms by which CEP functions as an anti-tumor drug, thereby exploring its value for clinical application. [ABSTRACT FROM AUTHOR]

Abstract Background Integrin αvβ3 has been proposed as crucial determinant for tumor sustained progression and a molecular marker for the estimation of tumor angiogenesis. Our study suggested that integrin αvβ3 could efficiently promote lung cancer cell proliferation and stem-like phenotypes in a tribbles homolog 3 (TRIB3) dependent manner. Result Integrin αvβ3 could mediate the activation of FAK/AKT pro-survival signaling pathway. Meanwhile, activated TRIB3 interacted with AKT to upregulated FOXO1 and SOX2 expression, resulting in sustained tumor progression in lung cancer. Our further analysis revealed that TRIB3 was significantly upregulated in lung tumor tissues and correlated with the poor outcome in clinical patients, indicating the potential role of TRIB3 in diagnostic and prognostic estimation for patients with lung cancer. Conclusion Our study showed here for the first time that integrin αvβ3 promote lung cancer development by activating the FAK/AKT/SOX2 axis in a TRIB3 dependent signaling pathway, and interrupting TRIB3/AKT interaction significantly improved the outcome of chemotherapy in tumor-bearing mice, representing a promising therapeutic strategy in lung cancer.

The mammalian target of rapamycin (mTOR) pathway is abnormally activated in lung cancer. However, the anti-lung cancer effect of mTOR inhibitors as monotherapy is modest. Here, we identified that ginsenoside Rh2, an active component of Panax ginseng C. A. Mey., enhanced the anti-cancer effect of the mTOR inhibitor everolimus both in vitro and in vivo. Moreover, ginsenoside Rh2 alleviated the hepatic fat accumulation caused by everolimus in xenograft nude mice models. The combination of everolimus and ginsenoside Rh2 (labeled Eve-Rh2) induced caspase-independent cell death and cytoplasmic vacuolation in lung cancer cells, indicating that Eve-Rh2 prevented tumor progression by triggering paraptosis. Eve-Rh2 up-regulated the expression of c-MYC in cancer cells as well as tumor tissues. The increased c-MYC mediated the accumulation of tribbles homolog 3 (TRIB3)/P62+ aggresomes and consequently triggered paraptosis, bypassing the classical c-MYC/MAX pathway. Our study offers a potential effective and safe strategy for the treatment of lung cancer. Moreover, we have identified a new mechanism of TRIB3/P62+ aggresomes-triggered paraptosis and revealed a unique function of c-MYC.

Introduction: Our study investigated the possible mechanisms of the role of the transcription factor Sox9 in the development and progression of kidney injury through regulation of the miR-96-5p/Trib3/IL-6 axis. Methods: Bioinformatics analysis was performed to identify differentially expressed genes in kidney injury and normal tissues. An in vivo animal model of kidney injury and an in vitro cellular model of kidney injury were constructed using LPS induction in 8-week-old female C57BL/6 mice and human normal renal tubular epithelial cells HK-2 for studying the possible roles of Sox9, miR-96-5p, Trib3, and IL-6 in kidney injury. Results: Sox9 was highly expressed in both mouse and cellular models of kidney injury. Sox9 was significantly enriched in the promoter region of miR-96-5p and repressed miR-96-5p expression. Trib3 was highly expressed in both mouse and cellular models of kidney injury and promoted inflammatory responses and kidney injury. In addition, Trib3 promoted IL-6 expression, which was highly expressed in kidney injury, and promoted the inflammatory response and extent of injury in kidney tissue. In vivo and in vitro experiments confirmed that the knockdown of Sox9 improved the inflammatory response and fibrosis of mouse kidney tissues and HK-2 cells, while the ameliorative effect of silencing Sox9 was inhibited by overexpression of IL-6. Conclusion: Collectively, Sox9 up-regulates miR-96-5p-mediated Trib3 and activates the IL-6 signaling pathway to exacerbate the inflammatory response, ultimately promoting the development and progression of kidney injury. [ABSTRACT FROM AUTHOR]

Idiopathic pulmonary fibrosis (IPF) is a fatal interstitial lung disease characterized by fibroblast activation, excessive deposition of extracellular matrix, and progressive scarring; the pathogenesis remains elusive. The present study explored the role of Tribbles pseudokinase 3 (TRIB3), a well-known stress and metabolic sensor, in IPF. TRIB3 is down-regulated in the lungs of IPF patients in comparison to control subjects. Deficiency of TRIB3 markedly inhibited A549 epithelial cells' proliferation and migration, significantly reducing wound healing. Conversely, overexpression of TRIB3 promoted A549 cell proliferation and transmigration while it inhibited its apoptosis. Meanwhile, overexpressed TRIB3 inhibited fibroblast activation and decreased ECM synthesis and deposition in MRC5 cells. TRIB3 attenuated pulmonary fibrosis by negative regulation of ATF4, while TRIB3 expression markedly inhibited ATF4 promoter-driven transcription activity and down-regulated ATF4 expression. A co-culture system showed that TRIB3 is important to maintain the normal epithelial–mesenchymal crosstalk and regulate fibroblast activation. Taken together, our data suggested that an axis of TRIB3–ATF4 is a key mediator in IPF which might be a potential target for fibroproliferative lung disease treatment. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid (PFOA), a widely used chemical substance, causes an increased risk of human type 2 diabetes (T2D), but its underlying mechanism is not well elucidated. The aim of the present study was to investigate whether PFOA regulates the functions of pancreatic β cells, which are specialized for the biosynthesis and secretion of insulin. The treatment of the mouse pancreatic β cell line (MIN6 cells) with PFOA caused a time- and dose-dependent inhibition of cell viability in CCK-8 assays. Annexin V/PI and TUNEL staining results confirmed that exposure to a high PFOA dose (500 μM) promoted apoptosis of β cells, while a low dose (300 μM) had no effects on β cell survival. PFOA treatment, even at a low dose, diminished glucose-stimulated insulin secretion (GSIS) in both primary islet perfusion and MIN6 cell experiments. RNA-sequencing data showed significantly increased expression of endoplasmic reticulum (ER) stress-associated genes, with tribbles homolog 3 (Trib3) ranking first among the altered genes. The activation of ER stress pathways was verified by qRT-PCR assays, and the ATF4/CHOP/TRIB3 pathway contributed to PFOA-induced β cell damage. The inhibition of TRIB3 expression significantly protected MIN6 cells from PFOA-induced GSIS defects and apoptosis by ameliorating ER stress. These findings reveal a link between ER stress and PFOA-induced β cell defects, opening up a new set of questions about the pathogenesis of T2D due to environmental chemicals. Highlights: PFOA exposure results in pancreatic β cell apoptosis. PFOA treatment diminishes glucose-stimulated insulin secretion in β cells. PFOA activates endoplasmic reticulum stress and increases TRIB3 expression. Inhibition of TRIB3 expression ameliorates PFOA-caused β cell dysfunction and apoptosis. [ABSTRACT FROM AUTHOR]

Acute promyelocytic leukemia (APL) is highly aggressive and is frequently associated with disseminated intravascular coagulation and high early death rates. Although all-trans retinoic acid (RA) induces complete remission in a high proportion of patients with APL, there are limited treatments for APL patients with RA resistance. Here we report an atypical APL patient, with an APL-like disease that developed very slowly without anti-leukemia therapy for nearly 2 years. During that time, the patient only intermittently received anti-HBV drugs, i.e., the combination of adefovir dipivoxil (ADV) and entecavir (ETV), leading us to hypothesize that ADV and/or ETV could inhibit APL progression. Our results showed that anti-HBV drugs ADV and ETV both exhibited significantly inhibitory effects on APL cells, and ADV indicated a much greater cytotoxic effect than ETV on APL cells. We further found that ADV significantly promoted APL cell differentiation and apoptosis, thereby restraining the progression of APL. Most importantly, our study uncovered a novel mechanism of ADV prohibiting APL progression, which was mediated, at least in part, by inhibition of TRIB3 and degradation of the oncoprotein PML-RARA, therefore leading to APL cell differentiation and apoptosis. Taken together, our study demonstrated that ADV, an anti-HBV drug, had significantly inhibitory effects on APL, and provided a novel therapeutic strategy for APL patients with RA resistance. [ABSTRACT FROM AUTHOR]

Background: Glioblastoma multiforme (GBM) is the most malignant adult brain tumor. Current standard of care treatments have very limited efficacy, being the patients´ overall survival 14 months and the 2-year survival rate less than 10%. Therefore, the treatment of GBM is an urgent unmet clinical need. Methods: The aim of this study was to investigate in vitro and in vivo the potential of ABTL0812, an oral anticancer compound currently in phase II clinical stage, as a novel therapy for GBM. Results: We showed that ABTL0812 inhibits cell proliferation in a wide panel of GBM cell lines and patient-derived glioblastoma stem cells (GSCs) with half maximal inhibitory concentrations (IC50s) ranging from 15.2 µM to 46.9 µM. Additionally, ABTL0812 decreased GSCs neurosphere formation. GBM cells aggressiveness is associated with a trans-differentiation process towards a less differentiated phenotype known as proneural to mesenchymal transition (PMT). ABTL0812 was shown to revert PMT and induce cell differentiation to a less malignant phenotype in GBM cell lines and GSCs, and consequently reduced cell invasion. As previously shown in other cancer types, we demonstrated that the molecular mechanism of action of ABTL0812 in glioblastoma involves the inhibition of Akt/mTORC1 axis by overexpression of TRIB3, and the activation of endoplasmic reticulum (ER) stress/unfolded protein response (UPR). Both actions converge to induce autophagy-mediated cell death. ABTL0812 anticancer efficacy was studied in vivo using subcutaneous and orthotopic intra-brain xenograft tumor models. We demonstrated that ABTL0812 impairs tumor growth and increases disease-free survival and overall survival of mice. Furthermore, the histological analysis of tumors indicated that ABTL0812 decreases angiogenesis. Finally, we investigated the combination of ABTL0812 with the standard of care treatments for GBM radiotherapy and temozolomide in an orthotopic model, detecting that ABTL0812 potentiates the efficacy of both treatments and that the strongest effect is obtained with the triple combination of ABTL0812+radiotherapy+temozolomide. Conclusions: Overall, the present study demonstrated the anticancer efficacy of ABTL0812 as single agent and in combination with the GBM standard of care treatments in models of glioblastoma and supports the clinical investigation of ABTL0812 as a potential novel therapy for this aggressive brain tumor type. [ABSTRACT FROM AUTHOR]

Pulmonary fibrosis (PF) is a chronic, progressive, fatal interstitial lung disease with limited available therapeutic strategies. We recently reported that the protein kinase glycogen synthase kinase-3β (GSK-3β) interacts with and inactivates the ubiquitin-editing enzyme A20 to suppress the degradation of the transcription factor CCAAT/enhancer-binding protein beta (C/EBPβ) in alveolar macrophages (AMs), resulting in a profibrotic phenotype of AMs and promoting the development of PF. Here, we showed that chronic lung injury upregulated the stress response protein tribbles homolog 3 (TRIB3), which interacted with GSK-3β and stabilized GSK-3β from ubiquitination and degradation. Elevated GSK-3β expression phosphorylated A20 to inhibit its ubiquitin-editing activity, causing the accumulation of C/EBPβ and the production of several profibrotic factors in AMs and promoting PF development. Activated C/EBPβ, in turn, increased the transcription of TRIB3 and GSK-3β, thereby establishing a positive feedback loop in AMs. The knockdown of TRIB3 expression or the pharmacologic disruption of the TRIB3‒GSK-3β interaction was an effective PF treatment. Our study reveals an intact profibrotic axis of TRIB3‒GSK-3β‒A20‒C/EBPβ in AMs, which represents a target that may provide a promising treatment strategy for PF.

BackgroundGlioblastoma multiforme (GBM) is the most malignant adult brain tumor. Current standard of care treatments have very limited efficacy, being the patients´ overall survival 14 months and the 2-year survival rate less than 10%. Therefore, the treatment of GBM is an urgent unmet clinical need. MethodsThe aim of this study was to investigate in vitro and in vivo the potential of ABTL0812, an oral anticancer compound currently in phase II clinical stage, as a novel therapy for GBM.ResultsWe showed that ABTL0812 inhibits cell proliferation in a wide panel of GBM cell lines and patient-derived glioblastoma stem cells (GSCs) with half maximal inhibitory concentrations (IC50s) ranging from 15.2 µM to 46.9 µM. Additionally, ABTL0812 decreased GSCs neurosphere formation. GBM cells aggressiveness is associated with a trans-differentiation process towards a less differentiated phenotype known as proneural to mesenchymal transition (PMT). ABTL0812 was shown to revert PMT and induce cell differentiation to a less malignant phenotype in GBM cell lines and GSCs, and consequently reduced cell invasion. As previously shown in other cancer types, we demonstrated that the molecular mechanism of action of ABTL0812 in glioblastoma involves the inhibition of Akt/mTORC1 axis by overexpression of TRIB3, and the activation of endoplasmic reticulum (ER) stress/unfolded protein response (UPR). Both actions converge to induce autophagy-mediated cell death. ABTL0812 anticancer efficacy was studied in vivo using subcutaneous and orthotopic intra-brain xenograft tumor models. We demonstrated that ABTL0812 impairs tumor growth and increases disease-free survival and overall survival of mice. Furthermore, the histological analysis of tumors indicated that ABTL0812 decreases angiogenesis. Finally, we investigated the combination of ABTL0812 with the standard of care treatments for GBM radiotherapy and temozolomide in an orthotopic model, detecting that ABTL0812 potentiates the efficacy of both treatments and that the strongest effect is obtained with the triple combination of ABTL0812+radiotherapy+temozolomide.ConclusionsOverall, the present study demonstrated the anticancer efficacy of ABTL0812 as single agent and in combination with the GBM standard of care treatments in models of glioblastoma and supports the clinical investigation of ABTL0812 as a potential novel therapy for this aggressive brain tumor type.

Previous studies have demonstrated that TRIB3 is closely related to insulin resistance, metabolic disorders and vascular diseases. Recently, it was reported that a 33 bp variable number of tandem repeats (VNTR) located in the TRIB3 promoter could considerably alter its transcriptional activity. Nonetheless, whether the shift of TRIB3 transcriptional activity has the effect of inducing diabetic vascular complications is still unclear. Therefore, in our study, we aimed to explore the relationship between the TRIB3 33bp VNTR and diabetic vascular complications. The TRIB3 33bp VNTR polymorphisms were determined by PCR and Sanger sequencing, a total of 798 eligible Chinese patients with type 2 diabetes (T2DM) were included in our study and then evaluated with clinical data. After adjusting for age, gender, BMI, smoking history, drinking history and duration of diabetes, we found that the high number of 33 bp tandem repeats (repeats>8) was significantly associated with an increase in the risk of cerebrovascular diseases compared with the low number of 33 bp tandem repeats (repeats≤6) in patients with T2DM(OR 2.66, 95% CI 1.29-5.47, p = 0.008). The intermediate number of 33bp tandem repeats (6 < repeat≤8) was markedly associated with a decreased risk of diabetic retinopathy compared with the low number of tandem repeats (OR 0.65, 95% CI 0.46--0.91, p = 0.012). Adjusting for gender, age and BMI, there was a significant difference in DBP levels among patients with the number of different 33 bp tandem repeats (Low vs. Intermediate vs. High, 81.6 ± 12.8 vs. 79.8 ± 12.4 vs. 78.7 ± 12.6 mmHg; p = 0.045). Subgroup analysis found that TRIB3 VNTR was significantly correlated with the difference in systolic blood pressure (SBP) in T2DM patients taking ACEI/ARB drugs (Low vs. Intermediate vs. High, 146.27 ± 18.23 vs. 140.01 ± 19.91 vs. 140.77 ± 18.64 mmHg; p = 0.018). Our results indicated that TRIB3 promoter 33bp VNTR is related to vascular diseases in T2DM patients, and may serve as a new biomarker for individualized prevention and therapy of T2DM. [ABSTRACT FROM AUTHOR]

Background: C/EBP homologous protein (CHOP) has been identified as a suitable therapeutic target to combat atherosclerosis but the mechanism has not been fully studied. Here, we sought to define the role and underlying mechanism of CHOP in atherosclerosis. Methods: Mouse models of atherosclerosis in ApoE-/- mice were established by high-fat feeding, where miR-208 expression was determined. Then atherosclerotic plaque tissues were isolated from the model mice. Loss- and gain-function assays were performed on trypsinized vascular smooth muscle cells (VSMCs) to test the in vitro effect of CHOP in controlling the tribbles homologue 3 (TRIB3)/microRNA-208 (miR-208)/tissue inhibitor of metalloproteinases-3 (TIMP3) axis in atherosclerosis by determining cell proliferation and migration as well as blood lipid levels. Moreover, expression of α-smooth muscle actin (α-SMA) and type I collagen expression was determined using immunofluorescence staining to assess plaque stability in mice. Results: miR-208 expression was elevated in atherosclerosis samples and miR-208 overexpression promoted proliferation and migration of VSMCs but diminished plaque stability in mice. TIMP3 was targeted by miR-208, which could be abrogated by upregulation of TIMP3. In addition, CHOP increased TRIB3 expression to upregulate miR-208 and to downregulate TIMP3, which potentiated VSMC proliferation and migration in vitro and in vivo. Conclusion: Taken together, inhibition of CHOP may inhibit the proliferation and migration of VSMCs as well as reduce the levels of TC, TG, and LDL-C but increase the level of HDL-C through the TRIB3/miR-208/TIMP3 axis, thereby inhibiting the progression of atherosclerosis. [ABSTRACT FROM AUTHOR]

Previous studies have demonstrated that TRIB3 is closely related to insulin resistance, metabolic disorders and vascular diseases. Recently, it was reported that a 33 bp variable number of tandem repeats (VNTR) located in the TRIB3 promoter could considerably alter its transcriptional activity. Nonetheless, whether the shift of TRIB3 transcriptional activity has the effect of inducing diabetic vascular complications is still unclear. Therefore, in our study, we aimed to explore the relationship between the TRIB3 33bp VNTR and diabetic vascular complications. The TRIB3 33bp VNTR polymorphisms were determined by PCR and Sanger sequencing, a total of 798 eligible Chinese patients with type 2 diabetes (T2DM) were included in our study and then evaluated with clinical data. After adjusting for age, gender, BMI, smoking history, drinking history and duration of diabetes, we found that the high number of 33 bp tandem repeats (repeats>8) was significantly associated with an increase in the risk of cerebrovascular diseases compared with the low number of 33 bp tandem repeats (repeats≤6) in patients with T2DM(OR 2.66, 95% CI 1.29–5.47, p = 0.008). The intermediate number of 33bp tandem repeats (6 < repeat≤8) was markedly associated with a decreased risk of diabetic retinopathy compared with the low number of tandem repeats (OR 0.65, 95% CI 0.46–0.91, p = 0.012). Adjusting for gender, age and BMI, there was a significant difference in DBP levels among patients with the number of different 33 bp tandem repeats (Low vs. Intermediate vs. High, 81.6 ± 12.8 vs. 79.8 ± 12.4 vs. 78.7 ± 12.6 mmHg; p = 0.045). Subgroup analysis found that TRIB3 VNTR was significantly correlated with the difference in systolic blood pressure (SBP) in T2DM patients taking ACEI/ARB drugs (Low vs. Intermediate vs. High, 146.27 ± 18.23 vs. 140.01 ± 19.91 vs. 140.77 ± 18.64 mmHg; p = 0.018). Our results indicated that TRIB3 promoter 33bp VNTR is related to vascular diseases in T2DM patients, and may serve as a new biomarker for individualized prevention and therapy of T2DM.

Tribbles 3 (TRIB3) modulates lipid and glucose metabolism, macrophage lipid uptake, with a gain-of-function variant associated with increased cardiovascular risk. Here we set out to examine the role of this pseudokinase in atherosclerotic plaque development. Human endarterectomy atherosclerotic tissue specimens analysed by immunofluorescence showed upregulated TRIB3 in unstable plaques and an enrichment in unstable regions of stable plaques. Atherosclerosis was induced in full body Trib3KO and Trib3WT littermate mice by injecting mPCSK9 expressing adeno-associated virus and western diet feeding for 12 weeks. Trib3KO mice showed expanded visceral adipose depot while circulatory lipid levels remained unaltered compared to wildtype mice. Trib3KO mice aortae showed a reduced plaque development and improved plaque stability, with increased fibrous cap thickness and collagen content, which was accompanied by increased macrophage content. Analysis of both mouse and human macrophages with reduced TRIB3 expression showed elongated morphology, increased actin expression and altered regulation of genes involved in extracellular matrix remodelling. In summary, TRIB3 controls plaque development and may be atherogenic in vivo. Loss of TRIB3 increases fibrous cap thickness via altered metalloproteinase expression in macrophages, thus inhibiting collagen and elastic fibre degradation, suggesting a role for TRIB3 in the formation of unstable plaques.

Pulmonary fibrosis (PF) has a high mortality rate, and its pathogenesis is unknown. TNF receptor-associated factor 6 (TRAF6), a signal transducer for inflammatory signaling, plays crucial roles in the pathogenesis of immune diseases. However, its function in PF remains unknown. Herein, we demonstrated that lungs from mice with bleomycin (BLM)-induced PF were characterized by decreased expression of TRAF6 in lung fibroblasts. Enhancing TRAF6 expression protected mice from BLM-induced PF coupled with a significant reduction in fibroblast differentiation. Furthermore, we demonstrated that overexpression of TRAF6 reversed the activation of myofibroblasts from PF mice by reducing the expression of Wnt3a and subsequently suppressing Wnt/β-catenin signaling. Additionally, the abundance of Tribbles pseudokinase 3 (TRIB3), a stress sensor, was negatively correlated with the abundance of TRAF6 in lung fibroblasts. TRIB3 overexpression decreased TRAF6 abundance by reducing TRAF6 stability in lung fibroblasts during PF. Mechanistic studies revealed that TRIB3 bound to TRAF6 and accelerated basal TRAF6 ubiquitination and degradation. Collectively, our data indicate that reduced TRAF6 expression in fibroblasts is essential for the progression of PF, and therefore, genetically increasing TRAF6 expression or disrupting the TRIB3-TRAF6 interaction could be potential therapeutic strategies for fibroproliferative lung diseases in clinical settings. [ABSTRACT FROM AUTHOR]

Tribbles pseudokinases, Tribbles homolog 1 (TRIB1), Tribbles homolog 2 (TRIB2), and Tribbles homolog 3 (TRIB3), bind to constitutive photomorphogenesis protein 1 (COP1) E3 ligase to mediate the regulation of β‐catenin expression. The interaction mechanism between COP1 E3 ligase and β‐catenin has not been addressed to date. Based on the functional presence of TRIBs in wingless‐related integration site (WNT) signaling, we analyzed their interaction patterns with β‐catenin and COP1. Here, through in silico approaches, we ascribe the COP1 binding pattern against TRIBs and β‐catenin. TRIB1 (355‐DQIVPEY‐361), TRIB2 (326‐DQLVPDV‐332), and TRIB3 (333‐AQVVPDG‐339) peptides revealed a shallow binding pocket at the COP1 interface to accommodate the V‐P sequence motif. Reinvigoration of the comparative binding pattern and subtle structural analysis via docking, molecular dynamics simulations, molecular mechanics Poisson–Boltzmann surface area, topological, and tunnel analysis revealed that both β‐catenin phosphodegron (DSGXXS) and TRIB (D/E/AQXVPD/E) motifs occupied a common COP1 binding site. Current study suggests a structural paradigm of TRIB homologs bearing a conserved motif that may compete with β‐catenin phosphodegron signature for binding to WD40 domain of COP1. Thorough understanding of the structural basis for TRIB‐mediated regulation of WNT/β‐catenin signaling may help in devising more promising therapeutic strategy for liver and colorectal cancers. [ABSTRACT FROM AUTHOR]

The mammalian target of rapamycin (mTOR) pathway is abnormally activated in lung cancer. However, the anti-lung cancer effect of mTOR inhibitors as monotherapy is modest. Here, we identified that ginsenoside Rh2, an active component of Panax ginseng C. A. Mey., enhanced the anti-cancer effect of the mTOR inhibitor everolimus both in vitro and in vivo. Moreover, ginsenoside Rh2 alleviated the hepatic fat accumulation caused by everolimus in xenograft nude mice models. The combination of everolimus and ginsenoside Rh2 (labeled Eve-Rh2) induced caspase-independent cell death and cytoplasmic vacuolation in lung cancer cells, indicating that Eve-Rh2 prevented tumor progression by triggering paraptosis. Eve-Rh2 up-regulated the expression of c-MYC in cancer cells as well as tumor tissues. The increased c-MYC mediated the accumulation of tribbles homolog 3 (TRIB3)/P62+ aggresomes and consequently triggered paraptosis, bypassing the classical c-MYC/MAX pathway. Our study offers a potential effective and safe strategy for the treatment of lung cancer. Moreover, we have identified a new mechanism of TRIB3/P62+ aggresomes-triggered paraptosis and revealed a unique function of c-MYC. Eve-Rh2 up-regulates the expression of c-MYC, which mediates the accumulation of TRIB3/P62+ aggresomes bypassing the classical c-MYC/MAX pathway, thereby triggering paraptosis and ultimately inhibiting tumor progression. [Display omitted] [ABSTRACT FROM AUTHOR]

Context: The upregulation of TRIB3 (Tribbles homolog 3), a stress-inducible gene encoding a pseudokinase, has been implicated in the development of insulin resistance in the skeletal muscle and liver of patients with obesity and type 2 diabetes. However, there is little information regarding TRIB3 expression in human adipose tissue. Objective: To investigate whether TRIB3 expression is dysregulated in human adipose tissue in the context of obesity and type 2 diabetes and whether TRIB3 expression in adipose tissues is associated with insulin resistance. Methods: We measured metabolic parameters and TRIB3 expression in abdominal subcutaneous and visceral adipose tissue in obese (with or without type 2 diabetes) and normal-weight women. Regulation of TRIB3 expression was studied in human adipocytes. Results: TRIB3 expression in both fat depots was higher in patients with obesity and/or type 2 diabetes; in addition, the expression level was significantly associated with insulin resistance. Incubating adipocytes under conditions mimicking the microenvironment of obese adipose tissue, including increased endoplasmic reticulum (ER) stress, induced TRIB3 expression. In human adipocytes, the overexpression of TRIB3 impaired insulin-stimulated protein kinase B (AKT) phosphorylation and caused dysregulation of the transcription of genes encoding bioactive molecules released from adipocytes, such as proinflammatory cytokines, adiponectin, and leptin. Pioglitazone, an insulin-sensitizing agent, reduced both these effects of TRIB3 and the ER stressor-induced expression of TRB3. Conclusion: Our data indicate that TRIB3 expression in adipose tissue is enhanced in patients with obesity and suggest that increased TRIB3 dysregulates adipocyte function, which may contribute to the development of insulin resistance. [ABSTRACT FROM AUTHOR]

Yutong Xing,1,2,* Peng Luo,2,* Rui Hu,1 Duanduan Wang,1 Gang Zhou,2 Jie Jiang3 1Department of Cardiothoracic Surgery, The Fifth Hospital of Xiamen, Xiamen, People’s Republic of China; 2Department of Cardiothoracic Surgery, The First Affiliated Hospital of Jiamusi University, Jiamusi, People’s Republic of China; 3Department of Thoracic Surgery, The First Affiliated Hospital of Xiamen University, Xiamen, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yutong Xing Department of Cardiothoracic SurgeryThe Fifth Hospital of Xiamen, Xiamen, Fujian 361101, People’s Republic of ChinaEmail xingyt2018@163.comBackground: The pseudokinase Tribbles 3 (TRIB3) is involved in many cellular processes and various cancers. In recent years, the importance of metabolic transformation in the maintenance of malignant tumors has become increasingly prominent. Abnormal metabolism of cancer cells is considered a hallmark of cancer. However, the exact role and molecular mechanism of TRIB3 in lung adenocarcinoma (LUAD) cell reprogramming is largely unknown.Methods: The oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) of cells were examined with a Seahorse XF Extracellular Flux Analyzer. In vitro and in vivo RT-qPCR, Western blotting, and functional assays were performed to explore the functional roles of TRIB3 in LUAD.Results: In the present study, we demonstrated that TRIB3 is remarkably upregulated in LUAD cell lines as well as tissues. TRIB3 knockdown significantly inhibited LUAD cell growth and suppressed LUAD cell invasion, while TRIB3 overexpression conferred the opposite effects. Moreover, silencing TRIB3 suppressed the tumorigenesis and metastatic ability of LUAD cells. Mechanistically, we demonstrated that silencing TRIB3 significantly impaired aerobic glycolysis ability in LUAD cells. Furthermore, our data indicated that TRIB3 knockdown decreased hypoxia-inducible factor (HIF)1α levels and targeted the glycolytic genes regulated by HIF1α.Conclusion: Together, our findings revealed a previously unappreciated function of TRIB3 in cancer cell metabolism and tumor progression, illustrating that TRIB3 could be considered a valuable therapeutic target for LUAD patients.Keywords: TRIB3, LUAD, aerobic glycolysis, HIF1α

Abstract Background Tribbles pseudokinase 3 (TRIB3) protein is a pseudokinase which plays an important role in cellular stress, metabolism, and tumor progression. However, the expression and function of TRIB3 in ovarian cancer is unknown. Methods TRIB3 expression was detected by immunohistochemistry in the ovarian tissue samples. Following down-regulation of TRIB3 by siRNA, multiple aspects of ovarian cancer cells were detected by the MTT assay, flow cytometry, scratch test and Transwell. Additionally, changes in related molecules and the MEK/ERK pathway were detected by western blotting. Finally, many bioinformatic methods, websites and databases, such as gene set enrichment analysis (GSEA), DVAID, Genemania, TISIDB and cBioPortal were used to study the TRIB3. Results The expression level of TRIB3 was higher in ovarian epithelial malignant tumors as compared to other groups. Patients with a high expression level of TRIB3 had significantly shorter survival times,which was consistent with the results of analysis of the KM-plot database. Down-regulation of TRIB3 expression significantly inhibited the proliferation, invasion, and migration capabilities of ovarian cancer cells, and induced apoptosis and cell cycle arrest. Following TRIB3 siRNA transfection, expression levels of relative proteins were found to be decreased. Additionally, analysis in DAVID website and GSEA revealed that TRIB3 expression was associated with multiple biological processes. Protein phosphorylation levels of MEK and ERK also decreased following TRIB3-siRNA transfection. The Genemania website was used to analyze the proteins that interact with TRIB3. Analysis of TRIB3 in the TISIDB database and cBioPortal website showed that ovarian cancer patients with high levels of mutation in TRIB3 had poor prognosis, and that the expression of TRIB3 was related to immunomodulation. Conclusions The TRIB3 was highly expressed and promoting the malignant behavior of ovarian cancer cells by activating the MEK-ERK signaling pathway. It was also found to be associated with genetic variations and immune modulators.

Abstract Objective To explore the biological function and molecular mechanism of Sp2 in hepatocellular carcinoma (HCC). Methods Tissue microarray immunohistochemistry and western blot were used to study the expression of Sp2 in hepatocellular tissue and adjacent non‐neoplastic tissues (ANT). In HCC cell lines, the role of Sp2 was determined by in vitro experiments such as CCK8, clone formation test, Transwell assay, wound‐healing assay, and flow cytometry apoptotic analysis, and its possible mechanism was analyzed. Results Compared with ANT, Sp2 expression in HCC tissues was significantly up‐regulated, which was strongly associated with stage of tumor and poor prognosis of patients. TCGA database were further confirmed these results. Besides, functional studies had shown that Sp2 knockdown not only leads to a decrease in cell proliferation and an increase in cell apoptosis but also inhibits the cells' abilities of migration and invasion. Sp2 silencing could inhibit the expression of TRIB3 protein and down‐regulate the endoplasmic reticulum stress (ERS) level of HCC. Conclusion Sp2 may play a part in promoting cancer by regulating TRIB3 protein, which may be a factor of prognostic and a potential new therapeutic target for HCC.

Pulmonary fibrosis (PF) has a high mortality rate, and its pathogenesis is unknown. TNF receptor-associated factor 6 (TRAF6), a signal transducer for inflammatory signaling, plays crucial roles in the pathogenesis of immune diseases. However, its function in PF remains unknown. Herein, we demonstrated that lungs from mice with bleomycin (BLM)-induced PF were characterized by decreased expression of TRAF6 in lung fibroblasts. Enhancing TRAF6 expression protected mice from BLM-induced PF coupled with a significant reduction in fibroblast differentiation. Furthermore, we demonstrated that overexpression of TRAF6 reversed the activation of myofibroblasts from PF mice by reducing the expression of Wnt3a and subsequently suppressing Wnt/β-catenin signaling. Additionally, the abundance of Tribbles pseudokinase 3 (TRIB3), a stress sensor, was negatively correlated with the abundance of TRAF6 in lung fibroblasts. TRIB3 overexpression decreased TRAF6 abundance by reducing TRAF6 stability in lung fibroblasts during PF. Mechanistic studies revealed that TRIB3 bound to TRAF6 and accelerated basal TRAF6 ubiquitination and degradation. Collectively, our data indicate that reduced TRAF6 expression in fibroblasts is essential for the progression of PF, and therefore, genetically increasing TRAF6 expression or disrupting the TRIB3-TRAF6 interaction could be potential therapeutic strategies for fibroproliferative lung diseases in clinical settings.

Objectives: Understanding the role of TRIB3 in cellular chemotherapy responsiveness and survival could facilitate its development as a prognostic marker that could be used to improve chemotherapeutic efficiency against specific tumors. Therefore, the role of TRIB3 to reflect the cytotoxic abilities of chemotherapeutic agents was clarified in the tested gastric cancer cell lines., Methods: We have comprehensively investigated the protein expression of TRIB3 in three gastric cancer cell lines AGS, TMK-1, and MKN-45 cells treated with the anticancer drugs, 5-fluorouracil, cisplatin, and docetaxel. The Cell Count kit-8 was used to evaluate cell viability. Immunoblotting was performed to assay protein levels after drug treatment. Flow cytometry was carried out to evaluate the levels of sub-G1 cell population., Results: Treatment of the tested gastric cancer cell lines dose-dependently decreased cell viability and protein levels of TRIB3 while increasing apoptosis. Overexpression of TRIB3 protects MKN-45 cells from endoplasmic reticulum stress-induced apoptosis but does not influence the induction of autophagy by anticancer drugs. In addition, overexpression of TRIB3 also rescued paroxetine-induced apoptosis and endoplasmic reticulum stress., Conclusions: Our previous and present results indicate that TRIB3 can protect gastric cancer cells against anticancer drug treatment and that downregulating TRIB3 may increase these cells' sensitivity to anticancer drugs. We thus suggest that the capability of anticancer drugs to downregulate TRIB3 can indicate tumors' potential susceptibility to these drugs., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Background: Previous studies have demonstrated that TRIB3 plays a carcinogenic role in tumor progression. However, the exploration of TRIB3 at the pan-cancer level has not been reported., Aims: This study aimed to conduct a comprehensive pan-cancer analysis of TRIB3., Objective: We explored the expression pattern and functional mechanism of TRIB3 on the basis of multiple databases., Method: We first explored the expression level of TRIB3 in the TCGA database. Then, the receiver operation characteristic curve (ROC), Kaplan-Meier plotter, and Cox regression were used to estimate the diagnostic and prognostic value of TRIB3, respectively. We also explored the relationship between TRIB3 and the infiltration of tumor immune cells, as well as the expression of immune checkpoint molecules. Gene enrichment and protein interaction network analysis were carried out to identify possible carcinogenic molecular mechanisms and functional pathways. Finally, we compared the non-promoter region methylation of TRIB3 in normal and tumor tissues and explored potential systems with unique functions in TRIB3-mediated tumorigenesis., Result: The expression level of TRIB3 was elevated in multiple tumor types, and the high expression of TRIB3 was associated with poor prognosis. TRIB3 had a higher frequency of genetic changes in several tumors and showed varying trends in TRIB3 methylation levels. Additionally, high expression of TRIB3 was also associated with infiltration of cancer-related fibroblasts and different types of immune cells and was positively correlated with the expression of immune checkpoint molecules. Furthermore, gene enrichment analysis suggested that TRIB3 may play a role in the malignant progression of cancer by participating in protein post-translational modifications and activating transcription initiation factors., Conclusion: Our pan-cancer analysis provided the potential carcinogenic role of TRIB3 in tumors and verified a promising target for clinical immune treatment., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: To explore the effect of TRIB3 on the osteogenic differentiation of human adiposederived mesenchymal stem cells (hASCs) and reveal the potential role of TRIB3 in bone regeneration. Methods: TRIB3-knockdown and TRIB3-overexpression hASCs were used to explore the effect of TRIB3 on osteogenic differentiation by alkaline phosphatase (ALP) staining, alizarin red S (ARS) staining, quantitative real-time polymerase chain reaction (qRT-PCR) and heterotopic bone formation. The regulation of miR-24-3p on TRIB3 was detected by qRT-PCR and western blot. Ribonucleic acid (RNA) sequencing was performed to investigate the downstream regulatory network of TRIB3. Results: TRIB3 promoted the osteogenic differentiation of hASCs both in vitro and in vivo. This process was regulated epigenetically by the post-transcriptional regulation of miR-24-3p, which could bind directly to the three prime untranslated region (3'UTR) of TRIB3 and inhibit TRIB3 expression. The downstream regulatory network of TRIB3-mediated osteogenic differentiation was related to calcium ion binding and cell metabolism, extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) and nuclear factor-κB (NF-κB) signalling pathways. Conclusion: TRIB3 is a promising therapeutic target for hASC-based bone tissue engineering and the epigenetic regulation of TRIB3 through miR-24-3p permits regulatory controllability, thus promoting osteogenesis through an important metabolic target while obtaining a safe and controllable effect via post-transcriptional epigenetic regulation. [ABSTRACT FROM AUTHOR]

Background: Dysregulated expression of TRIB3 and FABP1 have been previously observed in human cancer tissues. However, there are little information as to their expression change in dynamic gastric diseases and the functional roles.Methods: Tissues from a total of 479 patients, including 89 GS, 102 IM-GA, 144 EGC, and 144 AGC were collected. The protein expressions of TRIB3 and FABP1 were detected by immunohistochemical staining. Meanwhile, the potential functions of TRIB3 and FABP1 in GC were further analyzed by R software and some internet public databases, such as TCGA and DAVID.Results: During this multi-stage process that go through GS to EGC, the expression trend of TRIB3 and FABP1 protein was GS > IM-GA > EGC. Besides, the expression of TRIB3 protein continued to decrease in AGC, while the expression of FABP1 was abnormally increased. Hp infection was significantly associated with the decreased expression of TRIB3 and FABP1. In addition, the diagnostic efficiency of the combination of these two indicators to diagnose EGC was higher than that of a single indicator. Survival analysis showed that higher expression of TRIB3 or FABP1 could indicate a better prognosis of GC. The protein expressions of TRIB3 and FABP1 were significantly positively correlated. Moreover, CEACAM5 and PRAP1 were positively correlated with both TRIB3 and FABP1 expressions, while GABRP and THBS4 were negatively correlated. The macrophages M0 infiltration was positively correlated with both TRIB3 and FABP1 expressions.Conclusion: The protein expressions of TRIB3 and FABP1 gradually decreased with the gastric disease progress, and was positively correlated. Hp infection may reduce the protein expression of TRIB3 and FABP1. Combing TRIB3 and FABP1 expressions can improve the diagnostic efficiency for EGC. Either a high expression of TRIB3 or FABP1 indicates a better prognosis for GC. TRIB3 and FABP1 may interact with CEACAM5, PRAP1, GABRP and THBS4, and affect tumor immune microenvironment by regulating immune cells, and participate in the development and progression of GC.

Pulmonary fibrosis (PF) is a chronic, progressive, fatal interstitial lung disease with limited available therapeutic strategies. We recently reported that the protein kinase glycogen synthase kinase-3 β (GSK-3 β) interacts with and inactivates the ubiquitin-editing enzyme A20 to suppress the degradation of the transcription factor CCAAT/enhancer-binding protein beta (C/EBP β) in alveolar macrophages (AMs), resulting in a profibrotic phenotype of AMs and promoting the development of PF. Here, we showed that chronic lung injury upregulated the stress response protein tribbles homolog 3 (TRIB3), which interacted with GSK-3 β and stabilized GSK-3 β from ubiquitination and degradation. Elevated GSK-3 β expression phosphorylated A20 to inhibit its ubiquitin-editing activity, causing the accumulation of C/EBP β and the production of several profibrotic factors in AMs and promoting PF development. Activated C/EBP β , in turn, increased the transcription of TRIB3 and GSK-3 β , thereby establishing a positive feedback loop in AMs. The knockdown of TRIB3 expression or the pharmacologic disruption of the TRIB3‒GSK-3 β interaction was an effective PF treatment. Our study reveals an intact profibrotic axis of TRIB3‒GSK-3 β ‒A20‒C/EBP β in AMs, which represents a target that may provide a promising treatment strategy for PF. Elevated TRIB3 expression in macrophages positively correlates with the development of pulmonary fibrosis. TRIB3 interaction with GSK-3 β obstructs the ubiquitination and degradation of GSK-3 β. Targeting TRIB3‒GSK-3 β interaction reduces pulmonary fibrosis. [Display omitted] [ABSTRACT FROM AUTHOR]

Tumor‐associated macrophages (TAMs), one of the most common cell components in the tumor microenvironment, have been reported as key contributors to cancer‐related inflammation and enhanced metastatic progression of tumors. To explore the underlying mechanism of TAM‐induced tumor progression, TAMs were isolated from colorectal cancer patients, and the functional interaction with colorectal cancer cells was analyzed. Our study found that coculture of TAMs contributed to a glycolytic state in colorectal cancer, which promoted the stem‐like phenotypes and invasion of tumor cells. TAMs produced the cytokine transforming growth factor‐β to support hypoxia‐inducible factor 1α (HIF1α) expression, thereby upregulating Tribbles pseudokinase 3 (TRIB3) in tumor cells. Elevated expression of TRIB3 resulted in activation of the β‐catenin/Wnt signaling pathway, which eventually enhanced the stem‐like phenotypes and cell invasion in colorectal cancer. Our findings provided evidence that TAMs promoted colorectal cancer progression in a HIF1α/TRIB3‐dependent manner, and blockade of HIF1α signals efficiently improved the outcome of chemotherapy, describing an innovative approach for colorectal cancer treatment. [ABSTRACT FROM AUTHOR]

The potentiation of glycolysis is a leading driver of squamous cell carcinoma. Targeted modulation of the glycolytic process might be a pivotal tool for treating squamous cell carcinoma. Tribble homolog 3 (TRIB3) expression is elevated in some squamous cell carcinomas and correlates with poor prognosis. We investigated whether increased TRIB3 expression contributes to the progression of oral squamous cell carcinoma (OSCC) by modulating glycolysis. We analyzed the expression of TRIB3 in the TCGA database for clinical tissue samples, in vitro, and in vivo. Cell proliferation, migration, invasion, and apoptosis were observed by overexpressing or knocking down TRIB3. Crucially, the impact of TRIB3 on aerobic glycolysis in OSCC was also probed in our study, including glucose uptake, lactate content, ATP production, extracellular acidification rate, and oxygen consumption rate. Importantly, we examined the relationship between TRIB3 and the JNK/JUN pathway and whether it regulates glycolytic processes in OSCC cells through the JNK/JUN pathway. Finally, tumor growth in vivo was tested using Xenograft models to observe the effect of knockdown TRIB3. Our study identified TRIB3 as the most variable and prognostic in OSCC. A significant high expression of TRIB3 in OSCC cells was determined in vitro and promoted cell proliferation, migration, invasion, apoptosis, and aerobic glycolysis. Knockdown of TRIB3 produced opposite effects. In addition, these effects are regulated by the JNK/JUN pathway. The use of JNK inhibitor inhibited the pro-growth and glycolytic effects of TRIB3 on OSCC cells. Finally, we further determined that TRIB3 knockdown would effectively suppress tumor growth in vivo. This study reveals that TRIB3 promotes OSCC growth by regulating JNK/JUN pathway-mediated aerobic glycolysis, and TRIB3 may be a potential target for treating OSCC. • Downregulation of TRIB3 suppressed the survival of oral squamous cell carcinoma. • Inhibition of TRIB3 moderated the aerobic glycolysis of oral squamous cell carcinoma. • TRIB3 promotes the expression of glycolysis-related factors. • TRIB3 promotes aerobic glycolysis via regulating the JNK /JUN pathway in oral squamous cell carcinoma. • Knockdown of TRIB3 impairs cell tumorigenesis in oral squamous cell carcinoma. [ABSTRACT FROM AUTHOR]

BackgroundBladder cancer is a common malignant tumor characterized by high mortality and high management costs; however, it lacks useful molecular prognostic markers. Tribbles pseudokinase 3 (TRIB3) is a pseudokinase that participates in cell tumor progression and metabolism and whose function in bladder cancer is not precisely known.Main MethodsWe downloaded transcriptome data and clinical data of bladder cancer from associated databases and extracted the expression matrix of TRIB3 for multiple bioinformatics analysis. RT-PCR detected the expression of TRIB3 in bladder cancer cells. After knockdown of TRIB3 with siRNA, we investigated TRIB3 function using CCK8, Cell Cycle and Transwell assays.Key FindingsKaplan–Meier analysis of TRIB3 in the four cohorts showed that high expression of TRIB3 correlated with poor outcome. Expression of TRIB3 positively correlated with stage and grade and down-regulation of TRIB3 expression significantly inhibited proliferation, migration and cell cycle of bladder cancer cells.SignificanceTRIB3 is a potential prognostic marker and therapeutic target. It can be used to individualize the treatment of bladder cancer.