Tripartite Motif-containing Family Research Articles

TRIM26 inhibited osteosarcoma progression through destabilizing RACK1 and thus inactivation of MEK/ERK signaling

Osteosarcoma is a highly aggressive malignant tumor that is common in the pediatric population and has a high rate of disability and mortality. Recent studies have suggested that the tripartite motif-containing family genes (TRIMs) play critical roles in oncogenesis in several cancers. TRIM26, one of the TRIMs family genes, was more frequently reported to exert a tumor-suppressive role, while its detailed functional roles in the osteosarcoma progression were still unknown and require further investigation. Herein, we found that TRIM26 was markedly downregulated in osteosarcoma tissues and cells. Survival analysis revealed that higher expression of TRIM26 was associated with better prognosis and its expression was an independent protective factor in osteosarcoma. Functional analysis demonstrated that overexpression of TRIM26 inhibited osteosarcoma cell proliferation and invasion via inhibiting the EMT process and MEK/ERK signaling. In contrast, the silence of TRIM26 caused the opposite effect. RACK1, a member of the Trp-Asp repeat protein family, was identified as a novel target of TRIM26. TRIM26 could interact with RACK1 and accelerate the degradation of RACK1, thus inactivation of MEK/ERK signaling. Overexpression of RACK1 could attenuate the inhibitory effect of TRIM26 overexpression on p-MEK1/2 and p-ERK1/2, and silence of RACK1 could partly impair the effect of TRIM26 knockdown-induced upregulation of p-MEK1/2 and p-ERK1/2. Further, a series of gain- and loss-of-function experiments showed that decreased malignant behaviors including cell proliferation and invasion in TRIM26-upregulated cells were reversed when RACK1 was overexpressed, whereas RACK1 knockdown diminished the increased malignant phenotypes in TRIM26-silenced osteosarcoma cells. In conclusion, our study indicated that TRIM26 inhibited osteosarcoma progression via promoting proteasomal degradation of RACK1, thereby resulting in inactivation of MEK/ERK signaling, and impeding the EMT process.

Comparative Genomic Analysis of Warthog and Sus Scrofa Identifies Adaptive Genes Associated with African Swine Fever.

As warthogs (Phacochoerus africanus) have innate immunity against African swine fever (ASF), it is critical to understand the evolutionary novelty of warthogs to explain their specific ASF resistance. Here, we present two completed new genomes of one warthog and one Kenyan domestic pig as fundamental genomic references to elucidate the genetic mechanisms of ASF tolerance. Multiple genomic variations, including gene losses, independent contraction, and the expansion of specific gene families, likely molded the warthog genome to adapt to the environment. Importantly, the analysis of the presence and absence of genomic sequences revealed that the DNA sequence of the warthog genome had an absence of the gene lactate dehydrogenase B (LDHB) on chromosome 2 compared with the reference genome. The overexpression and siRNA of LDHB inhibited the replication of the African swine fever virus. Combined with large-scale sequencing data from 42 pigs worldwide, the contraction and expansion of tripartite motif-containing (TRIM) gene families revealed that TRIM family genes in the warthog genome are potentially responsible for its tolerance to ASF. Our results will help improve the understanding of genetic resistance to ASF in pigs.

E3 ubiquitin ligase-dependent regulatory mechanism of TRIM family in carcinogenesis

<p class="MsoNormal" style="text-align: justify;"><span lang="EN-US" style="mso-bidi-font-size: 10.5pt; font-family: Nunito; color: #212529; background: white;">Tripartite motif-containing (TRIM) proteins consist of over 80 proteins, the majority of which exhibit E3 ubiquitin ligase activity. E3 ligases have a critical role in various cellular processes by specifically recognizing and ubiquitinating substrate proteins to promote their proteasomal degradation or alter their activities. Numerous studies have indicated that TRIMs are involved in carcinogenesis through various mechanisms. However, the regulatory mechanisms delimitating TRIMs’ function as E3 ligases has not yet been specifically addressed in a previous review article. In this review, we focus on recent advancements in understanding how certain TRIMs function solely as E3 ligases during cancer cell proliferation, apoptosis, and metastasis. We comprehensively summarize the target proteins of TRIMs involved in disordered signaling pathways such as Wnt/</span><span lang="EN-US" style="mso-bidi-font-size: 10.5pt; font-family: 'Cambria',serif; mso-bidi-font-family: Cambria; color: #212529; background: white;">β</span><span lang="EN-US" style="mso-bidi-font-size: 10.5pt; font-family: Nunito; color: #212529; background: white;">-catenin, PI3K/AKT, NF-</span><span lang="EN-US" style="mso-bidi-font-size: 10.5pt; font-family: 'Cambria',serif; mso-bidi-font-family: Cambria; color: #212529; background: white;">κ</span><span lang="EN-US" style="mso-bidi-font-size: 10.5pt; font-family: Nunito; color: #212529; background: white;">B, p53, ERK, and STAT3, as well as those regulating the cell cycle and glycolysis. Following ubiquitination modification by TRIM E3 ligases, these target proteins either undergo proteasome-mediating degradation, maintain steady levels, or get activated/inactivated. This review provides a foundation for the development of E3 ligase-based cancer treatments.</span></p>

E3 ubiquitin ligase-dependent regulatory mechanism of TRIM family in carcinogenesis

<p>Tripartite motif-containing (TRIM) proteins consist of over 80 proteins, the majority of which exhibit E3 ubiquitin ligase activity. E3 ligases have a critical role in various cellular processes by specifically recognizing and ubiquitinating substrate proteins to promote their proteasomal degradation or alter their activities. Numerous studies have indicated that TRIMs are involved in carcinogenesis through various mechanisms. However, the regulatory mechanisms delimitating TRIMs’ function as E3 ligases has not yet been specifically addressed in a previous review article. In this review, we focus on recent advancements in understanding how certain TRIMs function solely as E3 ligases during cancer cell proliferation, apoptosis, and metastasis. We comprehensively summarize the target proteins of TRIMs involved in disordered signaling pathways such as Wnt/β-catenin, PI3K/AKT, NF-κB, p53, ERK, and STAT3, as well as those regulating the cell cycle and glycolysis. Following ubiquitination modification by TRIM E3 ligases, these target proteins either undergo proteasome-mediating degradation, maintain steady levels, or get activated/inactivated. This review provides a foundation for the development of E3 ligase-based cancer treatments.</p>

Tripartite motif 38 alleviates the pathological process of NAFLD–NASH by promoting TAB2 degradation

Nonalcoholic fatty liver disease (NAFLD) has become the most prevalent chronic liver disease worldwide, without any Food and Drug Administration-approved pharmacological intervention in clinic. Trim38, as an important member of the TRIM (tripartite motif-containing) family, was largely reported to be involved in the regulation of innate immune and inflammatory responses. However, the functional roles of TRIM38 in NAFLD remain largely unknown. Here, the expression of TRIM38 was first detected in liver samples of both NAFLD mice model and patients diagnosed with NAFLD. We found that TRIM38 expression was downregulated in NAFLD liver tissues compared with normal liver tissues. Genetic Trim38-KO in vivo showed that TRIM38 depletion deteriorated the high-fat diet and high fat and high cholesterol diet-induced hepatic steatosis and high fat and high cholesterol diet-induced liver inflammation and fibrosis. In particular, we found that the effects of hepatocellular lipid accumulation and inflammation induced by palmitic acid and oleic acid were aggravated by TRIM38 depletion but mitigated by TRIM38 overexpression in vitro. Mechanically, RNA-Seq analysis demonstrated that TRIM38 ameliorated nonalcoholic steatohepatitis progression by attenuating the activation of MAPK signaling pathway. We further found that TRIM38 interacted with transforming growth factor-β-activated kinase 1 binding protein 2 and promoted its protein degradation, thus inhibiting the transforming growth factor-β-activated kinase 1-MAPK signal cascades. In summary, our study revealed that TRIM38 could suppress hepatic steatosis, inflammatory, and fibrosis in NAFLD via promoting transforming growth factor-β-activated kinase 1 binding protein 2 degradation. TRIM38 could be a potential target for NAFLD treatment.

Emerging Roles of TRIM Family Proteins in Gliomas Pathogenesis.

Simple SummaryGliomas remain challenging tumors due to their increased heterogeneity, complex molecular profile, and infiltrative phenotype that are often associated with a dismal prognosis. In a constant search for molecular changes and associated mechanisms, the TRIM protein family has emerged as an important area of investigation because of the regulation of vital cellular processes involved in brain pathophysiology that may possibly lead to brain tumor development. Herein, we discuss the diverse role of TRIM proteins in glioma progression, aiming to detect potential targets for future intervention.Gliomas encompass a vast category of CNS tumors affecting both adults and children. Treatment and diagnosis are often impeded due to intratumor heterogeneity and the aggressive nature of the more malignant forms. It is therefore essential to elucidate the molecular mechanisms and explore the intracellular signaling pathways underlying tumor pathology to provide more promising diagnostic, prognostic, and therapeutic tools for gliomas. The tripartite motif-containing (TRIM) superfamily of proteins plays a key role in many physiological cellular processes, including brain development and function. Emerging evidence supports the association of TRIMs with a wide variety of cancers, exhibiting both an oncogenic as well as a tumor suppressive role depending on cancer type. In this review, we provide evidence of the pivotal role of TRIM proteins in gliomagenesis and exploit their potential as prognostic biomarkers and therapeutic targets.

Efp/TRIM25 and Its Related Protein, TRIM47, in Hormone-Dependent Cancers.

Increasing attention has been paid to the biological roles of tripartite motif-containing (TRIM) family proteins, which typically function as E3 ubiquitin ligases. Estrogen-responsive finger protein (Efp), a member of the TRIM family proteins, also known as TRIM25, was originally identified as a protein induced by estrogen and plays critical roles in promoting endocrine-related cancers, including breast cancer, endometrial cancer, and prostate cancer. The pathophysiological importance of Efp made us interested in the roles of other TRIM family proteins that share a similar structure with Efp. Based on a phylogenetic analysis of the C-terminal region of TRIM family proteins, we focused on TRIM47 as a protein belonging to the same branch as Efp. TRIM47 is a poor prognostic factor in both breast cancer and prostate cancer. Atypical lysine-27-like poly-ubiquitination was involved in the underlying mechanism causing endocrine resistance in breast cancer. We also discuss the functions of Efp and TRIM47 in other types of cancers and innate immunity by introducing substrates the are modified by poly-ubiquitination.

TRIM22 inhibits osteosarcoma progression through destabilizing NRF2 and thus activation of ROS/AMPK/mTOR/autophagy signaling

Osteosarcoma (OS) is a malignant bone tumor that mainly occurs in adolescents. It is accompanied by a high rate of lung metastasis, and high mortality. Recent studies have suggested the important roles of tripartite motif-containing (TRIM) family proteins in regulating various substrates and signaling pathways in different tumors. However, the detailed functional role of TRIM family proteins in the progression of OS is still unknown and requires further investigations. In this study, we found that tripartite motif-containing 22 (TRIM22) was downregulated in OS tissues and was hence associated with better prognosis. In vitro and in vivo functional analysis demonstrated that TRIM22 inhibits proliferation and metastasis of OS cells. Nuclear factor erythroid 2-related factor 2 (NRF2), a redox regulator, was identified as a novel target for TRIM22. TRIM22 interacts with and accelerates the degradation of NRF2 by inducing its ubiquitination dependent on its E3 ligase activity but independent of Kelch-like ECH-associated protein 1 (KEAP1). Further, a series of gain- and loss-of-function experiments showed that knockdown or overexpression of NRF2 reversed the functions of knockdown or overexpression of TRIM22 in OS. Mechanistically, TRIM22 inhibited OS progression through NRF2-mediated intracellular reactive oxygen species (ROS) imbalance. ROS production was significantly promoted and mitochondrial potential was remarkably inhibited when overexpressing TRIM22, thus activating AMPK/mTOR signaling. Moreover, TRIM22 was also found to inhibit Warburg effect in OS cells. Autophagy activation was found in OS cells which were overexpressed TRIM22, thus leading to autophagic cell death. Treatment with N-Acetylcysteine (NAC), a ROS scavenger or the autophagy inhibitor 3-Methyladenine (3-MA) abolished the decreased malignant phenotypes in TRIM22 overexpressing OS cells. In conclusion, our study indicated that TRIM22 inhibits OS progression by promoting proteasomal degradation of NRF2 independent of KEAP1, thereby activating ROS/AMPK/mTOR/Autophagy signaling that leads to autophagic cell death in OS. Therefore, our findings indicated that targeting TRIM22/NRF2 could be a promising therapeutic target for treating OS.

The Expression of TRIM6 Activates the mTORC1 Pathway by Regulating the Ubiquitination of TSC1-TSC2 to Promote Renal Fibrosis.

Renal fibrosis is considered as the final pathway of all types of kidney diseases, which can lead to the progressive loss of kidney functions and eventually renal failure. The mechanisms behind are diversified, in which the mammalian target of rapamycin (mTOR) pathway is one of the most important regulatory pathways that accounts for the disease. Several processes that are regulated by the mTOR pathway, such as autophagy, epithelial-mesenchymal transition (EMT), and endoplasmic reticulum (ER) stress, are tightly associated with renal fibrosis. In this study, we have reported that the expression of tripartite motif-containing (TRIM) protein 6, a member of TRIM family protein, was highly expressed in renal fibrosis patients and positively correlated with the severity of renal fibrosis. In our established in vitro and in vivo renal fibrosis models, its expression was upregulated by the Angiotensin II-induced nuclear translocation of nuclear factor-κB (NF-κB) p50 and p65. In HK2 cells, the expression of TRIM6 promoted the ubiquitination of tuberous sclerosis proteins (TSC) 1 and 2, two negative regulators of the mTORC1 pathway. Moreover, the knockdown of TRIM6 was found efficient for alleviating renal fibrosis and inhibiting the downstream processes of EMT and ER in both HK2 cells and 5/6-nephrectomized rats. Clinically, the level of TRIM6, TSC1/2, and NF-κB p50 was found closely related to renal fibrosis. As a result, we have presented the first study on the role of TRIM6 in the mTORC1 pathway in renal fibrosis models and our findings suggested that TRIM6 may be a potential target for the treatment of renal fibrosis.

The role of TRIM family proteins in autophagy, pyroptosis, and diabetes mellitus.

The ubiquitin-proteasome system, which is one of the systems for cell protein homeostasis and degradation, happens through the ordered and coordinated action of three types of enzymes, E1 ubiquitin-activating enzyme, E2 ubiquitin-carrier enzyme, E3 ubiquitin-protein ligase. Tripartite motif-containing (TRIM) family proteins are the richest subfamily of really interesting new gene E3 ubiquitin ligases, which play a critical role not only in many biological processes, including proliferation, apoptosis, pyroptosis, innate immunity, and autophagy, but also many diseases like cancer, diabetes mellitus, and neurodegenerative disease. Increasingevidence suggests that TRIM family proteins play a vital role in modulating autophagy, pyroptosis, and diabetes mellitus. The aim of this review is to discuss the role of TRIM proteins in the regulation of autophagy, pyroptosis, diabetes mellitus, and diabetic complications.

Tripartite motif‑containing14 regulates cell proliferation and apoptosis in cervical cancer via the Akt signaling pathway.

Tripartite motif-containing (TRIM) 14 is a protein of the TRIM family. Studies have indicated that TRIM14 may be used as an oncogene in tumor cells, such as osteosarcoma, non-small cell lung cancer and breast cancer through different pathways. However, the functions of TRIM14 in cervical cancer cells remain unclear. Therefore, this study aimed to investigate the functions of TRIM14 in cervical cancer cells and its underlying mechanism. Caski cells stably expressing TRIM14 and SiHa, and HeLa cells stably expressing TRIM14 short hairpin RNA were constructed by lentivirus-mediated overexpression or knockdown systems. The effects of TRIM14 on proliferation and apoptosis of cervical cancer cells were detected by Cell Counting Kit-8 (CCK-8) assay and flow cytometry, respectively. In addition, reverse transcription-quantitative (RT-q) PCR and western blotting were used to investigate the expression levels of TRIM14 and of signaling pathway marker protein including P21, caspase-3, cleaved caspase-3, Akt and phosphorylated Akt. The results of RT-qPCR and western blotting revealed that TRIM14 was highly expressed in human cervical cancer tissues and cell lines compared with adjacent normal tissues and normal cervical epithelial cells. TRIM14 also regulated cell proliferation and apoptosis of human SiHa, HeLa and Caski cervical cancer cell lines through the Akt signaling pathway. Additionally, TRIM14 protein levels were related to the clinical and pathological features of cervical cancer. CCK-8 assay and flow cytometry demonstrated that TRIM14 expression could promote cervical cancer cell proliferation and autophagy suppression. Taken together, TRIM14-induced cell proliferation and apoptosis inhibition may by evoked by the activation of the Akt pathway. This study demonstrated the role of TRIM14 in cervical cancer, and reveals its mechanism of action as a potential therapeutic target for cervical cancer.

TRIM37 Mediates Chemoresistance and Maintenance of Stemness in Pancreatic Cancer Cells via Ubiquitination of PTEN and Activation of the AKT-GSK-3β-β-Catenin Signaling Pathway.

PurposeThe tripartite motif-containing family member TRIM37 is involved in a number of important biological and pathological processes, and it has recently been shown to be an essential regulator of protein ubiquitination and a contributor to tumorigenesis. We previously showed that TRIM37 is overexpressed in and promotes the proliferation and invasion of pancreatic cancer (PC).MethodsSphere formation, flow cytometric, qRT-PCR, western blot, colony formation, EdU incorporation, mouse xenograft model, TUNEL and IHC assays were performed to detect the role of TRIM37 in stemness and chemoresistance of PC in vitro and in vivo. Bioinformatics analysis and dual-luciferase reporter assays were used to determine which intracellular pathways might mediate the effects of TRIM37 in PC cells. Immunofluorescent(IF) staining, co-immunoprecipitation(CO-IP), protein stability and ubiquitination assays were performed to investigate the relationship between TRIM37 and PTEN.ResultsTRIM37 modulates the ubiquitination and degradation of the tumor suppressor phosphatase and tensin homolog (PTEN), which negatively regulates the AKT–GSK-3β–β-catenin signaling pathway, thereby sustaining aberrant activation of PC cells. High expression of TRIM37 combined with low expression of PTEN correlates with poor survival of PC patients.ConclusionsCollectively, our results suggest that inhibition of the TRIM37–AKT–GSK-3β–β-catenin axis may be a promising strategy for treatment of PC.

TRIM22 inhibits respiratory syncytial virus replication by targeting JAK-STAT1/2 signaling.

Respiratory syncytial virus (RSV) infection is a major cause of lower respiratory tract disease. Although RSV causes major economic losses every year, effective treatments have not been found so far. Recent studies have shown that the tripartite motif-containing (TRIM) superfamily plays an essential role in the immune response. In this study, we found that TRIM22 had an inhibitory effect on RSV infection, and downregulation of TRIM22 moderately enhanced RSV replication. Our data further demonstrated that RSV infection induced TRIM22 expression through the activation of JAK-STAT1/2 signaling. RSV infection also induced TRIM22 expression. Taken together, these data points showed that the TRIM family member, TRIM22, had an essential role in resisting RSV infection, and this effect was closely related to the JAK-STAT1/2 pathway. Our results provide promising evidence for a novel target for the prevention and treatment of RSV.

Emerging Roles of Tripartite Motif-Containing Family Proteins (TRIMs) in Eliminating Misfolded Proteins.

Protein quality control (PQC) is pivotal for eukaryotic cells to eliminate misfolded proteins and maintain cellular homeostasis. A decreased or increased capacity of PQC is associated with various diseases, e.g., neurodegenerative diseases and cancers. Recently, increasing evidences have suggested that tripartite motif-containing family proteins (TRIMs) are the key players in PQC regulation. Most TRIMs are E3 ubiquitin ligases, such as TRIM11/19/25, which, through the ubiquitination modifications, can contribute to effectively remove the cellular misfolded proteins or protein aggregates via the UPS pathway. In this review, we summarized the participation of TRIM members in misfolded protein elimination through distinct pathways, including the ubiquitin–proteasome system (UPS), autophagy system, and ER-associated degradation (ERAD).

Abstract P3-06-11: TRIM39 is a poor prognostic factor for breast cancer patients and promotes proliferation and migration of breast cancer cells

Abstract [Background] Tripartite motif-containing (TRIM) proteins typically function as E3 ubiquitin ligases and involved in many biological processes including cancer biology. We previously reported that TRIM25/Efp which stimulated the degradation of a negative cell-cycle regulator, 14-3-3 sigma,is a poor prognostic factor for breast cancer patients (Nature 417, 871, 2002; Clin Cancer Res 11, 6148, 2005) and that TRIM44 overexpressed in breast cancer enhanced NF-κB signaling (Int J Mol Sci 18, pii:E1931, 2017). In the present study, we focused on the prognostic value and the roles in breast cancer of a TRIM family protein, TRIM39. [Methods] Tissue samples of invasive breast cancer were obtained from 124 Japanese female primary breast cancer patients who underwent surgical treatment at Toranomon Hospital, Tokyo, Japan. This study was approved by the ethical committee in Toranomon Hospital. We performed immunohistochemical analysis with a polyclonal antibody against TRIM39. Immuno-stained slides were evaluated for intensity and proportion of nuclear staining. We examined the relationship between immunoreactivity of TRIM39 and clinico-pathological parameters and patients’ prognosis. In order to investigate TRIM39 biological function in breast cancer cells, we used MCF-7 and MDA-MB-231, breast cancer cell lines. We knocked down expression of TRIM39 and evaluated cell proliferation and cell migration. We investigated gene expression profiles affected by knockdown of TRIM39 with microarray analysis (Affymetrix, Clariom S). [Results] Among clinico-pathological parameters, higher pathological stage, higher pathological tumor size and higher nuclear grade were significantly associated with strong immunoreactivity of TRIM39. TRIM39 immunoreactivity was significantly associated with distant disease-free survival (p<0.001) and overall survival (p<0.001) of patients. Multivariate analysis revealed that the TRIM39 status was an independent prognostic factor for distant disease-free survival (p<0.001) and overall survival (p<0.001) of patients. Knockdown of TRIM39 markedly decreased proliferation of both cell lines and also inhibited migration of MDA-MB-231 cells. Microarray analysis and qRT-PCR revealed that TRIM39 knockdown downregulated CDCA3 and CDC25C in both cell lines. [Discussion] The present study suggested that strong expression of TRIM39 protein may be used as a prognostic biomarker for breast cancer patients. Moreover, TRIM39 would be a potential therapeutic target for breast cancer, considering TRIM39 knockdown caused attenuated proliferation and migration in breast cancer cells. CDCA3 and CDC25C were identified as genes regulated by TRIM39. CDCA3 was shown to promote proliferation by activating the NF-κB/cyclin D1 signaling pathway. CDC25C was reported to increase cell survival by suppressing apoptosis signal-regulating kinase 1(ASK1). Thus, these proteins could be involved in the role of TRIM39 in proliferation of breast cancer cells. [Conclusion] TRIM39 is a poor prognostic factor for breast cancer patients and would be a potential therapeutic target for breast cancer. Citation Format: Takuya Ogura, Kotaro Azuma, Junichiro Sato, Keiichi Kinowaki, Kazuhiro Ikeda, Hidetaka Kawabata, Satoshi Inoue. TRIM39 is a poor prognostic factor for breast cancer patients and promotes proliferation and migration of breast cancer cells [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-06-11.

Chronic aerobic exercise improves insulin sensitivity and modulates Nrf2 and NF‑κB/IκBα pathways in the skeletal muscle of rats fed with a high fat diet.

The present study aimed to investigate the molecular mechanisms of the ameliorative effects of chronic aerobic exercise on non-alcoholic steatohepatitis (NASH) in rat skeletal muscle. Female Sprague-Dawley rats (n=6–9 per group) were divided into four groups: i) Rats fed with normal chow; ii) exercise rats fed with normal chow + exercise (run on a rotarod for 30 min per day from 9–12 weeks); iii) rats fed with a high-fat diet (HFD); iv) rats fed with an HFD + exercise. All HFD rats were fed with an HFD consisting of 30% fat from fish oil throughout the study for 12 weeks. Exercise decreased the levels of hepatic lipogenic markers carbohydrate-responsive element-binding protein, fat-specific protein 27 and liver X receptor and improved systemic glucose and insulin intolerance in the NASH animal model. The beneficial effects may have been mediated partly via the tripartite motif-containing family protein 72 (TRIM72)/PI3K/Akt/mTOR pathway, accompanied with an upregulation of glucose transporter 4 in the skeletal muscle. The exercise regimen activated the master regulator of antioxidant enzymes, nuclear factor erythroid 2-related factor 2, with upregulation of superoxide dismutase [Cu-Zn] expression and a corresponding decrease in kelch-like ECH-associated protein 1 expression, but failed to decrease the levels of the oxidative marker malondialdehyde in the HFD rat skeletal muscle. Chronic exercise decreased the expression of the inflammation marker NF-κB, followed by a decrease in interleukin-6 and tumor necrosis factor-α levels, as verified by a corresponding increase in the level of NF-κB inhibitor α expression. Exercise may exert its beneficial effects by improving muscle insulin sensitivity via the TRIM72/PI3K/Akt/mTOR pathway, contributing to the improvement of systemic insulin intolerance, and finally leading to decreased hepatic lipogenesis during NASH. The attenuation of insulin resistance by exercise may be partly achieved through a decrease in the level of inflammation and an increased antioxidant response.

Tripartite motif-containing 15 overexpression in non-small cell lung cancer is associated with poor patient prognoses.

Purpose: This study aimed to comprehensively investigate the differential expression and prognostic indicators of the tripartite motif-containing (TRIM) gene family in non-small cell lung cancer (NSCLC).Methods: The Cancer Genome Atlas (TCGA) Research Network and three datasets from Gene Expression Omnibus (GEO) database were used to assess TRIM gene family expression patterns in NSCLC. Quantitative real-time PCR and immunohistochemistry (IHC) were conducted to confirm differentially expressed genes (DEGs). Kaplan-Meier survival analysis and univariate Cox regression analysis were carried out to analyze the association between TRIM gene expression and NSCLC prognoses. Gene set enrichment analysis (GSEA) was carried on for the predict the biological processes.Results: Of the 78 TRIM family members measured, TRIM15 was selected due to the DEGs and the prognostic value regarding NSCLC. In lung squamous cell carcinoma (LUSC), the Log2 fold change (Log2FC) of TRIM15 was 5.16 (p= 0.00575), whereas in lung adenocarcinoma (LUAD), it was 6.37 (p =6.78E-07). TRIM15 upregulation was related to poor prognoses in both LUSC (HR 1.353; 95%CI 1.023-1.789; p =0.034) and LUAD (HR 1.560; 95%CI 1.159-2.101; p =0.003). Using immunohistochemistry, TRIM15 expression was significantly higher in NSCLC tissues compared with that of matched normal tissues (p =0.0009), and similar findings were generated with tissue microarray analysis (p<0.0001).Conclusion: TRIM15 could act as a diagnostic predictor or therapeutic target for lung cancer treatments.

Tripartite motif 31 promotes resistance to anoikis of hepatocarcinoma cells through regulation of p53-AMPK axis

Anoikis-resistance is an essential feature of cancer cells to obtain successful metastasis, whereas the molecular mechanism involved in this process of hepatocellular carcinoma (HCC) cells is not fully understood. Here we demonstrated that tripartite motif-containing (TRIM) 31, a new member of the TRIM family, was significantly upregulated in the anchorage-deprived HCC cells compared with their attached counterpart. When we blocked TRIM31 expression by its specific interference RNAs, the anoikis-resistance of HCC cells was significantly reversed. We further verified that overactivation of AMPK pathway was responsible for TRIM31-mediated resistance to anoikis of HCC cells; and TRIM31 could directly target p53, the upstream suppressor of AMPK pathway, and mediate K48-linked ubiquitous degradation of p53 in a RING-domain-dependent way. Therefore we demonstrated that TRIM31 promoted anoikis-resistance by targeting p53 for degradation and subsequently overactivating AMPK pathway. Thus our study defined for the first time the role of TRIM31 in the anoikis-resistant process of HCC cells， and it may pave a new avenue for manipulation of metastatic cancer by targeting TRIM31.

Tripartite motif-containing protein 3 plays a role of tumor inhibitor in cervical cancer

Many studies have been reported that tripartite motif-containing (TRIM) proteins play important roles in various cellular processes and involved in many diseases. TRIM3, a member of TRIM family, has been proved that it plays important roles in various cancers. Nevertheless, its effects on cervical cancer reminded unknown. This study aimed to explore TRIM3 function in cervical cancer cells. The results of quantitative real-time RT-PCR and western blotting showed that the TRIM3 expression was very low in five cervical cancer cell lines. The TRIM3 overexpression weakened cell viability, and promote apoptosis of C-33A and SiHa cells in vitro, and inhibit tumor growth in vivo, which suggested that TRIM3 could reduce proliferation of cervical cancer cells. Moreover, TRIM3 up-regulation enhanced caspase-3 activity and increased the expressions of cleaved caspase-3 and p53, at the same time decreased p38 phosphorylation level. In addition, TRIM3 down-regulation had opposite effects on cell proliferation and expressions of the three proteins, which could be suppressed by p38-specific inhibitor (SB203580). In conclusion, TRIM3 had the ability to suppress cell proliferation by inactivating p38 signaling pathway, which indicated that it might act as a tumor inhibitor and an underlying therapeutic target for cervical cancer.

Tripartite motif-containing 28 bridges endothelial inflammation and angiogenic activity by retaining expression of TNFR-1 and -2 and VEGFR2 in endothelial cells.

Angiogenesis and inflammation are regarded as important factors in the pathogenesis of chronic inflammation, cancer, and wound healing. Recent studies have supported prior evidence that common signaling pathways are involved in angiogenesis and inflammatory responses; however, key factors controlling both processes remain unclear. Although tripartite motif-containing (TRIM)-28 is known to have an immunosuppressive role in immune cells, its expression level and role in endothelial cells (ECs) are still unclear. In this study, we investigated the role of TRIM28 in inflammatory responses and angiogenic activity of ECs for the first time. We showed that TRIM28 is the most abundant TRIM family member and is localized in nuclei of ECs. Small interfering RNA-mediated knockdown of TRIM28 strikingly suppressed expression of TNF receptor (TNFR)-1 and -2, decreased TNF-α-induced phosphorylation of IKKα/β and IκBα and degradation of IκBα and nuclear translocation of p65, and suppressed basal level and TNF-α-induced expression of chemokines and adhesion molecules, including VCAM-1, IL-6, ICAM-1, E-selectin, and monocyte chemoattractant protein (MCP)-1. Unexpectedly, IL-8 was potentiated by TRIM28 knockdown in ECs in an NF-κB-inducing kinase-dependent manner. Meanwhile, knockdown of TRIM28 inhibited expression of VEGF receptor 2 and suppressed VEGF-induced proliferation and tube formation by ECs. Finally, knockdown of TRIM28 suppressed recruitment of ECs in vivo in a murine synthetic basement membrane model. In summary, we found that TRIM28 acts as a central factor in controlling endothelial inflammatory responses and angiogenic activities by retaining expression of TNFR-1 and -2 and VEGF receptor 2 in ECs.-Wang, Y., Li, J., Huang Y., Dai, X., Liu, Y., Liu, Z., Wang, Y., Wang, N., Zhang, P. Tripartite motif-containing 28 bridges endothelial inflammation and angiogenic activity by retaining expression of TNFR1 and -2 and VEGFR2 in endothelial cells.