The role of hepatitis B virus surface protein in inducing Sertoli cell ferroptosis

BACKGROUNDS

Hepatitis B virus infection could result in male infertility with sperm defects and dysfunction. Sertoli cells are essential for testis function and play a crucial role in spermatogenesis. Sertoli cell death contributes to spermatogenesis impairment, leading to poor sperm quality. Ferroptosis has been implicated as a mechanism of Sertoli cell death. The issue in studying the relationship between hepatitis B virus and Sertoli cell ferroptosis has not yet been addressed.

OBJECTIVES

To explore the mechanisms underlying ferroptosis in hepatitis B virus-exposed Sertoli cells.

MATERIALS AND METHODS

Human Sertoli cells were treated in vitro with levels of 25, 50, and 100 μg/mL of hepatitis B virus surface protein (HBs). Cell viability and levels of glutathione, malondialdehyde, cellular ferrous ion (Fe2+ ), lipid peroxidation, and N6-methyladenosine in Sertoli cells were detected. The level of glutathione peroxidase 4, transferrin receptor 1, ferritin heavy chain, tripartite motif (TRIM) 37, methyltransferase like 3, and insulin-like growth factor 2 mRNA binding protein 2 was examined. Cell transfection was carried out to alter expression of ferroptosis-related proteins. qPCR and immunoblotting were performed to measure protein expression level. Immunoprecipitation was applied to determine the protein and protein-RNA interaction. Luminescence analysis was performed to identify the target of methyltransferase like 3.

RESULTS

HBs exposure triggered ferroptosis featured with increased intracellular Fe2+ ion, reduced cell viability and expression of glutathione peroxidase 4 in Sertoli cells. HBs treatment significantly increased TRIM37 expression, which suppressed glutathione peroxidase 4 expression through ubiquitination. TRIM37 silencing attenuated the effect of HBs exposure-regulated cell viability and ferroptosis. HBs upregulated N6-methyladenosine modification in TRIM37 3'-UTR by increasing methyltransferase like 3 expression. The binding of N6-methyladenosine reader insulin-like growth factor 2 mRNA binding protein 2 and TRIM37 3'-UTR enhanced the stability of TRIM37 mRNA.

CONCLUSION

HBs can decrease human Sertoli cell viability by promoting ferroptosis induced by the loss of glutathione peroxidase 4 activity through TRIM37-mediated ubiquitination of glutathione peroxidase 4. The findings highlight the role of TRIM37/glutathione peroxidase 4 signaling responsible for ferroptosis regulation in hepatitis B virus-infected Sertoli cells.

TRIM37 promotes gallbladder cancer proliferation by activating the Wnt/β-catenin pathway via ubiquitination of Axin1

BACKGROUND

Gallbladder cancer (GBC) is among the most lethal malignancies in the world, with a prognosis that is extremely poor. The results of previous studies suggest that tripartite motif containing 37 (TRIM37) contributes to the progression of numerous types of cancer. Nevertheless, there is little knowledge about the molecular mechanisms and functions of TRIM37 in GBC.

METHODS

A clinical significance assessment was conducted on TRIM37 following its detection by immunohistochemistry. In vitro and in vivo functional assays were performed to investigate the role of TRIM37 in GBC.

RESULTS

In this study, TRIM37 is upregulated in GBC tissues, which is associated with decreased histological differentiation, advanced TNM stage, and shorter overall survival rates. In vitro, TRIM37 knockdown inhibited cell proliferation and promoted apoptosis, and in vivo, TRIM37 knockdown suppressed GBC growth. Contrary to this, cell proliferation is increased in GBC cells when overexpression of TRIM37 is expressed. Mechanistic investigations revealed that TRIM37 promotes GBC progression through activation of the Wnt/β‑catenin signaling pathway via degradation of Axin1.

CONCLUSION

The present study suggests that TRIM37 contributes to the development of GBC and thus provides an important biomarker for predicting GBC prognosis and an effective target for therapeutic intervention.

TRIM37 exacerbates hepatic ischemia/reperfusion injury by facilitating IKKγ translocation

BACKGROUND

Hepatic ischemia/reperfusion (I/R) injury is one of the major pathological processes associated with various liver surgeries. However, there is still a lack of strategies to protect against hepatic I/R injury because of the unknown underlying mechanism. The present study aimed to identify a potential strategy and provide a fundamental experimental basis for treating hepatic I/R injury.

METHOD

A classic 70% ischemia/reperfusion injury was established. Immunoprecipitation was used to identify direct interactions between proteins. The expression of proteins from different subcellular localizations was detected by Western blotting. Cell translocation was directly observed by immunofluorescence. HE, TUNEL and ELISA were performed for function tests.

RESULT

We report that tripartite motif containing 37 (TRIM37) aggravates hepatic I/R injury through the reinforcement of IKK-induced inflammation following dual patterns. Mechanistically, TRIM37 directly interacts with tumor necrosis factor receptor-associated factor 6 (TRAF6), inducing K63 ubiquitination and eventually leading to the phosphorylation of IKKβ. TRIM37 enhances the translocation of IKKγ, a regulatory subunit of the IKK complex, from the nucleus to the cytoplasm, thereby stabilizing the cytoplasmic IKK complex and prolonging the duration of inflammation. Inhibition of IKK rescued the function of TRIM37 in vivo and in vitro.

CONCLUSION

Collectively, the present study discloses some potential function of TRIM37 in hepatic I/R injury. Targeting TRIM37 might be potential for treatment against hepatic I/R injury.Targeting TRIM37 might be a potential treatment strategy against hepatic I/R injury.

Aerobic glycolysis and tumor progression of hepatocellular carcinoma are mediated by ubiquitin of P53 K48-linked regulated by TRIM37

BACKGROUND

Hepatocellular carcinoma (HCC) is the most common primary liver cancer in the world. In malignant liver cancer, the increase of aerobic glycolysis indicates that the possibility of tumorigenesis is greatly enhanced. TRIM37 is a member of the TRIM family of proteins that possesses E3 ubiquitin ligase activity and has been implicated in the occurrence and prognosis of many different tumors. However, the stability of P53 plays an important role in preventing tumorigenesis. The mechanism by which TRIM37 regulates the stability of P53 through ubiquitin in the progression of hepatocellular carcinoma is still unclear.

MATERIALS AND METHODS

Real-time quantitative polymerase chain reaction (qRT-PCR) and Western blotting were used to detect the expression of mRNA and protein in HCC cells. Lactic acid production, glucose uptake, and ATP levels were measured by BioVision kit. The following were used to assess the in vitro function of TRIM37 in HCC cells: cell counting kit-8 (CCK-8), colony formation assay, cell migration and invasion assay, and flow cytometry. We observed the effect of TRIM37 on the growth of transplanted tumors in nude mice. Co-Immunoprecipitation (Co-IP) revealed a binding relationship between TRIM37 and P53.

RESULTS

The expression of TRIM37 in hepatocellular carcinoma (HCC) tissues was higher than that of normal tissues according to an analysis of The Cancer Genome Atlas (TCGA) database.Loss-of-function assays indicated that TRIM37 inhibited the proliferation, colony formation, migration, and invasion of liver cancer cells. The mechanism is as follows: TRIM37 interacts with the P53 protein to induce E3 ligase activity, ubiquitination, and degradation, further promoting the malignant characteristics of hepatocellular carcinoma, thus promoting the process of glycolysis. Genetic knockdown of P53 reversed the promoting function of TRIM37 on the growth and metastasis of hepatocellular carcinoma cells.

CONCLUSIONS

Our study showed that the TRIM37-P53 axis plays a role in the progression of liver cancer, and thus is a potential target for the treatment of liver cancer.

Metformin inhibits the proliferation and invasion of ovarian cancer cells by suppressing TRIM37-induced TRAF2 ubiquitination

Ovarian cancer is the leading cause of death in gynecological malignancies worldwide. Our previous studies have proved that metformin inhibited the proliferation and invasion of ovarian cancer in vitro and in vivo. However, the underlying mechanisms have not been fully elucidated. Immunohistochemistry was carried out to detect the expression of tripartite motif‐containing 37 (TRIM37), Ki‐67, and MMP‐9 in ovarian cancer and normal tissues. The influence of TRIM37 on the proliferation and invasion of ovarian cancer cells was verified by the real‐time cellular analysis proliferation test, colony formation test, and Transwell assay. Western blot analysis and immunoprecipitation were used to detect the expression of the nuclear factor‐κB (NF‐κB) pathway and the interaction between TRIM37 and tumor necrosis factor receptor‐associated factor 2 (TRAF2). Ubiquitination detection was carried out to detect the ubiquitination level of TRAF2. The present study revealed that TRIM37 expression was significantly increased in ovarian cancer tissues compared with normal control tissues, and its overexpression was closely associated with proliferation and metastasis. Metformin inhibited the NF‐κB signaling pathway by downregulating TRIM37. Metformin also inhibited the ubiquitination of TRAF2 induced by TRIM37 overexpression. Metformin inhibits the proliferation and invasion of ovarian cancer cells by suppressing TRIM37‐induced TRAF2 ubiquitination.

TRIM37 Augments AP-2γ Transcriptional Activity and Cellular Localization via K63-linked Ubiquitination to Drive Breast Cancer Progression

Activator Protein 2 gamma (AP-2γ) is a master transcription factor that plays a critical role in the development and progression of breast cancer. However, the underlying mechanism is still unclear. Herein, using a proteomics approach, we identified Tripartite motif-containing 37 (TRIM37) as a novel coactivator of AP-2γ-mediated transcription in breast cancer cells. We demonstrate that TRIM37 facilitates AP-2γ chromatin binding to directly regulate the AP-2γ mediated transcriptional program. We also show that TRIM37 achieves this by stimulating K63 chain-linked ubiquitination of AP-2γ, promoting protein localization from the cytoplasm to the nucleus. In clinical analyses, we find TRIM37 is upregulated in multiple breast cancer datasets, supporting our findings that the TRIM37-AP-2γ interaction is essential for breast cancer tumor growth. Overall, our work reveals that TRIM37 is an oncogenic coactivator of AP-2γ in breast cancer and provides a novel therapeutic target for treating the disease.

Global cellular response to chemical perturbation of PLK4 activity and abnormal centrosome number

Centrosomes act as the main microtubule organizing center (MTOC) in metazoans. Centrosome number is tightly regulated by limiting centriole duplication to a single round per cell cycle. This control is achieved by multiple mechanisms, including the regulation of the protein kinase PLK4, the most upstream facilitator of centriole duplication. Altered centrosome numbers in mouse and human cells cause p53-dependent growth arrest through poorly defined mechanisms. Recent work has shown that the E3 ligase TRIM37 is required for cell cycle arrest in acentrosomal cells. To gain additional insights into this process, we undertook a series of genome-wide CRISPR/Cas9 screens to identify factors important for growth arrest triggered by treatment with centrinone B, a selective PLK4 inhibitor. We found that TRIM37 is a key mediator of growth arrest after partial or full PLK4 inhibition. Interestingly, PLK4 cellular mobility decreased in a dose-dependent manner after centrinone B treatment. In contrast to recent work, we found that growth arrest after PLK4 inhibition correlated better with PLK4 activity than with mitotic length or centrosome number. These data provide insights into the global response to changes in centrosome number and PLK4 activity and extend the role for TRIM37 in regulating the abundance, localization, and function of centrosome proteins.

Liver pathology and biochemistry in patients with mutations in TRIM37 gene (Mulibrey nanism)

BACKGROUND AND AIMS

Mulibrey nanism (MUL) is a multiorgan disease caused by recessive mutations in the TRIM37 gene. Chronic heart failure and hepatopathy are major determinants of prognosis in MUL patients, which prompted us to study liver biochemistry and pathology in a national cohort of MUL patients.

METHODS

Clinical, laboratory and imaging data were collected in a cross-sectional survey and retrospectively from hospital records. Liver histology and immunohistochemistry for 10 biomarkers were assessed.

RESULTS

Twenty-one MUL patients (age 1-51 years) with tumour suspicion showed moderate congestion, steatosis and fibrosis in liver biopsies and marginally elevated levels of serum GGT, AST, ALT and AST to platelet ratio index (APRI) in 20%-66%. Similarly, GGT, AST, ALT and APRI levels were moderately elevated in 12%-69% of 17 MUL patients prior to pericardiectomy. In a cross-sectional evaluation of 36 MUL outpatients, GGT, total bilirubin and galactose half-life (Gal½) correlated with age (r = 0.45, p = .017; r = 0.512, p = .007; r = 0.44, p = .03 respectively). The frequency of clearly abnormal serum values of 15 parameters analysed, however, was low even in patients with signs of restrictive cardiomyopathy. Transient elastography (TE) of the liver revealed elevated levels in 50% of patients with signs of heart failure and TE levels correlated with several biochemistry parameters. Biomarkers of fibrosis, sinusoidal capillarization and hepatocyte metaplasia showed increased expression in autopsy liver samples from 15 MUL patients.

CONCLUSION

Liver disease in MUL patients was characterized by sinusoidal dilatation, steatosis and fibrosis with individual progression to cirrhosis and moderate association of histology with cardiac function, liver biochemistry and elastography.

TRIM37 Promotes Pancreatic Cancer Progression through Modulation of Cell Growth, Migration, Invasion, and Tumor Immune Microenvironment

TRIM37 dysregulation has been observed in several cancer types, implicating its possible role in tumorigenesis. However, the role of TRIM37 in pancreatic cancer progression remains unclear. In the present study, we observed that TRIM37 knockdown resulted in reduced proliferation, clonogenicity, migration, and invasion ability of pancreatic cancer cells. Furthermore, an in vivo study using an orthotopic syngeneic animal model further confirmed that reduced expression of TRIM37 in cancer cells suppressed tumor growth in vivo. Moreover, in mice bearing TRIM37 knockdown pancreatic cancer cells, the proportion of CD11b⁺F4/80⁺MHCII^low immunosuppressive macrophages was significantly reduced in tumor milieu, which might be due to the regulatory role of TRIM37 in cytokine production by pancreatic cancer cells. Collectively, these findings suggest a key role of TRIM37 in promoting pancreatic cancer progression.

TRIM37 interacts with PTEN to promote the growth of human T-cell acute lymphocytic leukemia cells through regulating PI3K/AKT pathway

Background

TRIM37 has been reported to be associated with the tumorigenesis of cancers. However, the role of TRIM37 in T-cell acute lymphoblastic leukemia (T-ALL) remains unclear. This study aimed to characterize the effect of TRIM37 on T-ALL.

Methods

TRIM37 expression in T-ALL patients and T-ALL cell lines was determined by qRT-PCR and Western blot. Knockdown or overexpression of TRIM37 was conducted by transferring small-interfering TRIM37 or lentivirus-mediated transducing into T-ALL cells. CCK-8 assay and flow cytometry assay were conducted to analyze the proliferation and apoptosis of T-ALL cells. Co-immunoprecipitation experiments were conducted to investigate the relationship between TRIM37 and PTEN and the ubiquitination of PTEN.

Results

Our results suggested that TRIM37 expression was upregulated in the blood of T-ALL patients and T-ALL cell lines. Knockdown of TRIM37 noticeably inhibited the proliferation and promoted apoptosis of T-ALL cells. Ectopic expression of TRIM37 promoted the proliferation and suppressed the apoptosis rate of MOLT-4 cells and enhanced the phosphorylation of AKT. Moreover, TRIM37 interacted with PTEN and accelerated the degradation of PTEN via TRIM37-mediated ubiquitination in T-ALL cells. Moreover, TRIM37 reduced the sensitivity of T-ALL cells to bortezomib treatment. Additionally, PI3K/AKT signaling pathway was involved in the function of TRIM37 in T-ALL. TRIM37 contributed to the proliferation of T-ALL cells and reduced the susceptibility of T-ALL cells to bortezomib treatment through ubiquitination of PTEN and activating PI3K/AKT signaling pathway.

Conclusions

Our study suggested that TRIM37 could be considered as a therapeutic target for T-ALL.

TRIM37: a critical orchestrator of centrosome function

Loss of function mutations in the E3 ubiquitin ligase TRIM37 result in MULIBREY nanism, a disease characterized by impaired organ growth and a high propensity to develop different tumor types. Additionally, increased copy number of TRIM37 is a feature of some breast cancers and neuroblastomas. The molecular role played by TRIM37 in such loss and gain of function conditions has been a focus of research in the last decade, which led notably to the identification of critical roles of TRIM37 in centrosome biology. Specifically, deletion of TRIM37 results in the formation of aberrant centrosomal proteins assemblies, including Centrobin-PLK4 assemblies, which can act as extra MTOCs, thus resulting in defective chromosome segregation. Additionally, TRIM37 overexpression targets the centrosomal protein CEP192 for degradation, thereby preventing centrosome maturation and increasing the frequency of mitotic errors. Interestingly, increased TRIM37 protein levels sensitize cells to the PLK4 inhibitor centrinone. In this review, we cover the emerging roles of TRIM37 in centrosome biology and discuss how this knowledge may lead to new therapeutic strategies to target specific cancer cells.

miR-942-5p prevents sepsis-induced acute lung injury via targeting TRIM37

MicroRNAs (miRNAs) have been demonstrated to play pivotal roles in the pathogenesis of sepsis-induced acute lung injury (ALI). In this work, we aimed to clarify the potential role and the underlying mechanism of miR-942-5p in a lipopolysaccharide (LPS)-induced A549 cell injury model. The cell injury was evaluated by CCK-8 assay, flow cytometry and enzyme-linked immunosorbent assay (ELISA). The expression levels of miR-942-5p and tripartite motif-containing protein 37 (TRIM37) were measured by real-time PCR and Western blot, and their association was then validated by bioinformatics, luciferase reporter assay and RNA pull-down assay. We found that the expression of miR-942-5p was decreased in LPS-treated A549 cells. Furthermore, LPS treatment suppressed A549 cell viability, promoted apoptosis and increased the levels of inflammatory cytokines. Conversely, overexpression of miR-942-5p increased cell viability, reduced apoptosis and alleviated inflammatory cytokine secretion in the presence of LPS. Moreover, miR-942-5p directly targeted TRIM37 by binding to the 3'-UTR of TRIM37 mRNA. Upregulation of TRIM37 effectively reversed the anti-apoptotic and anti-inflammatory effects of miR-942-5p in LPS-induced A549 cells. Our findings suggested that miR-942-5p protected against LPS-induced cell injury through inhibiting apoptosis and inflammation in A549 cells by negatively regulating TRIM37.

Increased alveolar epithelial TRAF6 via autophagy-dependent TRIM37 degradation mediates particulate matter-induced lung metastasis

Epidemiological and clinical studies have shown that exposure to particulate matter (PM) is associated with an increased incidence of lung cancer and metastasis. However, the underlying mechanism remains unclear. Here, we demonstrated the central role of PM-induced neutrophil recruitment in promoting lung cancer metastasis. We found that reactive oxygen species (ROS)-mediated alveolar epithelial macroautophagy/autophagy was essential for initiating neutrophil chemotaxis and pre-metastatic niche formation in the lungs in response to PM exposure. During PM-induced autophagy, the E3 ubiquitin ligase TRIM37 was degraded and protected TRAF6 from proteasomal degradation in lung epithelial cells, which promoted the NFKB-dependent production of chemokines to recruit neutrophils. Importantly, ROS blockade, autophagy inhibition or TRAF6 knockdown abolished PM-induced neutrophil recruitment and lung metastasis enhancement. Our study indicates that host lung epithelial cells and neutrophils coordinate to promote cancer metastasis to the lungs in response to PM exposure and provides ideal therapeutic targets for metastatic progression.Abbreviations: ACTA2/α-SMA: actin alpha 2, smooth muscle, aorta; ATII: alveolar type II; Cho-Traf6 siRNA: 5'-cholesterol-Traf6 siRNA; EMT: epithelial-mesenchymal transition; HBE: human bronchial epithelial; HCQ: hydroxychloroquine; MAPK: mitogen-activated protein kinase; NAC: N-acetyl-L-cysteine; NFKB: nuclear factor of kappa light polypeptide gene enhancer in B cells; NS: normal saline; PM: particulate matter; ROS: reactive oxygen species; TRAF6: TNF receptor-associated factor 6; TRIM37: tripartite motif-containing 37.

TRIM37 orchestrates renal cell carcinoma progression via histone H2A ubiquitination-dependent manner

Background

Ubiquitylation modification is one of the multiple post-transcriptional process to regulate cellular physiology, including cell signaling, cycle regulation, DNA repair and transcriptional regulation. Members of TRIM family proteins could be defined as E3 ubiquitin ligases as they contain a RING-finger domain, and alterations of TRIM proteins are involved into a broad range of diverse disorders including cancer. TRIM37 is a novel discovered E3 ubiquitin ligase and acts as a oncoprotein in multiple human neoplasms, however its biological role in RCC still remains elusive.

Methods

RCC microarray chips and public datasets were screened to identify novel TRIMs member as TRIM37, which was dysregulated in RCC. Gain or loss of functional cancer cell models were constructed, and in vitro and in vivo assays were performed to elucidate its tumorigenic phenotypes. Interactive network analyses were utilized to define intrinsic mechanism.

Results

We identified TRIM37 was upregulated in RCC tumors, and its aberrant function predicted aggressive neoplastic phenotypes, poorer survival endings. TRIM37 promoted RCC cells EMT and malignant progression via TGF-β1 signaling activation, as a consequence of directly mediated by ubiquitinating-H2A modifications.

Conclusions

Our findings identified a previously unappreciated role of TRIM37 in RCC progression and prognostic prediction. Importantly, we declared a novel ubiquitination-dependent link between TRIM ubiquitin ligases and TGF-β1 signaling in regulating cancerous malignancies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-01980-0.

LncRNA NEAT1 acts as a key regulator of cell apoptosis and inflammatory response by the miR-944/TRIM37 axis in acute lung injury

Acute lung injury (ALI), a common complication of sepsis, is characterized by the impairment and injury of pulmonary function. The nuclear factor kappa-B (NF-κB) pathway is activated in ALI. Tripartite motif-containing 37 (TRIM37) can activate the NF-κB pathway and is closely associated with inflammation. The purpose of our study is to reveal the role of TRIM37 in ALI. The present study revealed that TRIM37 presented high levels in lung tissues of ALI mice, and knockdown of TRIM37 alleviated lipopolysaccharide (LPS)-induced lung injury, inflammatory response, and cell apoptosis in vivo. In addition, knockdown of TRIM37 inhibited the inflammatory response, and cell apoptosis of LPS-treated WI-38 cells. Mechanistically, miR-944 was identified to bind with and negatively regulate TRIM37. Furthermore, NEAT1 was indicated to act as a competitive endogenous RNA to promote TRIM37 expression by sequestering miR-944. Detailly, NEAT1 bound with miR-944, negatively modulated miR-944 expression, and positively modulated TRIM37 expression. The rescue assays suggested that overexpression of TRIM37 rescued the influence of NEAT1 knockdown on cell apoptosis and inflammatory response. Overall, NEAT1 facilitated cell apoptosis and inflammatory response of WI-38 cells by the miR-944/TRIM37 axis in sepsis-induced ALI, implying that NEAT1 may provide a novel insight for the treatment of sepsis-induced ALI.

TRIM37 overexpression is associated with chemoresistance in hepatocellular carcinoma via activating the AKT signaling pathway

BACKGROUND

Hepatocellular carcinoma (HCC) is the most common primary liver cancer in the worldwide. Sorafenib is approved for first-line therapy against advanced HCC, but chemo-resistance is still a leading cause of tumor relapse and treatment failure in HCC. Thus, there is a significant clinical need to identify effective strategies to overcome drug resistance on the disease.

METHODS

The protein and mRNA expression of TRIM37 in HCC cell lines and patient tissues were determined using Real-time PCR and Western blot, respectively. HCC tissue samples were analyzed by IHC to investigate the association between TRIM37expression and the clinicopathological characteristics of HCC patients. Functional assays, such as MTT, FACS, and Tunel assay, are used to determine the oncogenic role of TRIM37 in human HCC progression. Furthermore, western blotting and luciferase assay were used to determine the mechanism of TRIM37promotes chemoresistance in HCC.

RESULTS

We found that both the mRNA and protein expression of TRIM37 was markedly upregulated in HCC cell lines and tissues, especially in Sorafenib-resistance HCC tissues. Moreover, high TRIM37 expression was associated with poor prognosis with HCC patients. TRIM37 overexpression confers Sorafenib resistance on HCC cells; however, inhibition of TRIM37 sensitized HCC cell lines to Sorafenib cytotoxicity. Additionally, TRIM37 upregulated the levels of AKT activity and phosphorylated AKT, thereby activating canonical AKT signaling.

CONCLUSION

Our findings suggest that targeting TRIM37 signaling may represent a promising strategy to enhance Sorafenib response in HCC patients with chemoresistant.

TRIM37 contributes to malignant outcomes and CDDP resistance in gastric cancer

Background: TRIM37 (Tripartite Motif Containing 37) is an E3 ubiquitin ligase for histone H2A and inhibits transcription in several genes. However, it is not known whether it plays a role in gastric cancer (GC). In this study, we tested whether TRIM37 acts as a cancer-promoting factor by being overexpressed in GC. Methods: We analyzed GC cell lines and 124 primary tumors, which were curatively resected in our hospital between 2001 and 2003. Results: Overexpression of the TRIM37 protein was detected in almost all GC cell lines and GC samples (76 out of 124 cases) and was significantly correlated with lymphatic and venous invasion, advanced T-Stage, N-Stage, histology and high recurrence rate. Patients with TRIM37 overexpressing tumors had a worse survival rate than those with non-expressing tumors (P=0.0057). Moreover, TRIM37 positivity was identified as an independent factor predicting worse outcomes (P=0.018, Hazard ratio 3.41). The apoptotic cell analysis showed that the knockdown of TRIM37 increased apoptosis in comparison with the control. In TRIM37 overexpressing GC cells, knockdown of TRIM37 suppressed the migration and invasion. Conclusions: TRIM37 plays a crucial role in tumor malignant potential through its overexpression and highlight its usefulness as a prognostic factor and potential therapeutic target in GC.

ASB16-AS1 up-regulated and phosphorylated TRIM37 to activate NF-κB pathway and promote proliferation, stemness, and cisplatin resistance of gastric cancer

BACKGROUND

Long non-coding RNA (lncRNA) ASB16 antisense RNA 1 (ASB16-AS1) is recognized as an oncogene in several cancer types, but its relation to GC is unknown. Tripartite motif containing 37 (TRIM37) has been proven to accelerate the development of gastric cancer (GC), whereas the molecular mechanism assisted ASB16-AS1 and TRIM37 in regulating GC progression remains unclear.

METHODS

Differentially expressed lncRNAs in GC samples were analyzed based on Gene Expression Omnibus (GEO) data. CCK-8 and colony formation assays were applied to determine the proliferative ability of GC cells. Stem cell-like phenotype of GC cells was assessed by sphere formation assay and flow cytometry analysis. Luciferase reporter assay, RNA immunoprecipitation (RIP), pulldown, and co-immunoprecipitation (Co-IP) were performed to verify the interplay of RNA molecules.

RESULTS

ASB16-AS1 was upregulated in GC samples according to GEO data and qRT-PCR analysis. ASB16-AS1 strengthened the proliferative ability and stem cell-like characteristics in GC cells. More importantly, ASB16-AS1 encouraged GC cell growth in vivo. Mechanistically, ASB16-AS1 strengthened TRIM37 expression by sequestering miR-3918 and miR-4676-3p. ASB16-AS1 activated NF-kappa B (NF-κB) pathway by cooperating with ATM serine/threonine kinase (ATM) to induce TRIM37 phosphorylation.

CONCLUSION

In summary, ASB16-AS1 exerted oncogenic functions in GC through modulating TRIM37 expression at both mRNA and protein levels.

A novel long non-coding RNA RP11-286H15.1 represses hepatocellular carcinoma progression by promoting ubiquitination of PABPC4

Hepatocellular carcinoma (HCC) is a malignancy found at high frequency around the world. Unfortunately, the scarcity of effective early diagnostic methods invariably results in poor outcomes. Long noncoding RNAs (lncRNAs) are known to regulate the progression of hepatocellular carcinoma (HCC). A novel lncRNA RP11-286H15.1(OTTHUMG00000186042) has been identified and associated with HCC; however, the potential role of RP11-286H15.1 in HCC remains undefined. The transcript abundance of RP11-286H15.1 in 80 pairs of HCC samples and cell lines was evaluated by qRT-PCR analysis. The functional role of RP11-286H15.1 in HCC was tested in vivo and in vitro. The mechanisms underlying the role of RP11-286H15.1 in HCC were explored by RNA pulldown, transcriptome sequencing, and RNA immunoprecipitation (RIP), ubiquitination and fluorescence in situ hybridization (FISH) assays as well as Western blot analysis. The qRT-PCR and FISH assays revealed that RP11-286H15.1 was significantly decreased in HCC, and implied a shorter survival time. RP11-286H15.1 overexpression inhibited HCC cell proliferation and metastasis in vitro and in vivo, whereas RP11-286H15.1 knockdown produced the opposite results. Furthermore, we confirmed that RP11-286H15.1 (620-750 nucleotides) binds to poly(A) binding protein 4 (PABPC4) and promotes its ubiquitination, thus, reducing the stability of TRIM37 and CDC27 mRNAs. Our study demonstrates that a novel lncRNA, RP11-286H15.1, represses HCC progression by promoting PABPC4 ubiquitination. These findings highlight potential therapeutic targets for HCC.

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

Purpose

The 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).

Methods

Sphere 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.

Results

TRIM37 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.

Conclusions

Collectively, our results suggest that inhibition of the TRIM37–AKT–GSK-3β–β-catenin axis may be a promising strategy for treatment of PC.

CD4+ T Cell Defects in a Mulibrey Patient With Specific TRIM37 Mutations

Mulibrey (muscle-liver-brain-eye) syndrome (MUL) is an autosomal recessive disorder caused by mutations in the TRIpartite motif (TRIM)37 gene, encoding for TRIM37 a member of the TRIM E3 ubiquitin ligase protein family. MUL patients are characterized by growth retardation, dysmorphic features, and a wide range of abnormalities affecting different organs. However, T-cell abnormalities have not been observed in MUL subjects, to date. Here we described the immunological features of a MUL child carrying recently identified TRIM37 mutations, a 17q22 deletion of maternal origin combined with a TRIM37 variant of paternal origin. Here we found quantitative and functional defects in CD4⁺ T cells from this MUL case. Low levels of TRIM37 protein were specifically detected in CD4⁺ T cells of MUL patient and associated with their altered proliferation and cytokine production. Of note, both CD4⁺ and CD8⁺ T lymphocytes of MUL child displayed an effector memory phenotype compared with healthy children. This clinical case research highlighted the possible role of TRIM37 in the control of immune cell number and function, especially in CD4⁺ T cells. Finally, this study may contribute to the novel mechanistic studies aim of identifying, in depth, the role of the TRIM37 protein in the immune system.

ROS/NF-κB Signaling Pathway-Mediated Transcriptional Activation of TRIM37 Promotes HBV-Associated Hepatic Fibrosis

Hepatic fibrosis is an inflammatory response that leads to liver cirrhosis in the most advanced condition. Liver cirrhosis is a leading cause of deaths associated with liver diseases; hence, understanding the underlying mechanisms of hepatic fibrosis is critical to develop effective therapies. Tripartite motif (TRIM) family proteins have been shown to be involved in liver fibrosis; however, the exact role of several TRIM proteins in this process remained unexplored. In this study, we investigated the role of TRIM37 in hepatitis B virus (HBV)-associated hepatic fibrosis. We analyzed TRIM37 expression in hepatic fibrosis patients and performed functional and mechanistic studies in tissue culture and mouse models to identify the role of TRIM37 in hepatic fibrosis. We found an increased expression of TRIM37 in hepatic fibrosis patients. Mechanistically, we showed that TRIM37 physically interacts with SMAD7 and promotes ubiquitination-mediated degradation of SMAD7, and that SMAD7 is a key mediator of TRM37-induced hepatic fibrosis. Furthermore, we showed nuclear factor κB (NF-κB) activation mediated by reactive oxygen species (ROS) is necessary for the transcriptional induction of TRIM37 during HBV infection. Our study shows TRIM37 as an important promoter of HBV-associated hepatic fibrosis.

TRIM37 is highly expressed during mitosis in CHON-002 chondrocytes cell line and is regulated by miR-223

Multiple molecular disorders can affect mechanisms regulating proliferation and differentiation of growth plate chondrocytes. Mutations in the TRIM37 gene cause the Mulibrey nanism, a heritable growth disorder. Since chondrocytes are instrumental in long bone growth that is deficient in nanism, we hypothesized that TRIM37 defect could contribute to dysregulation of the chondrocyte cell cycle. Western blotting, confocal microscopy and imaging flow cytometry determined TRIM37 expression in CHON-002 cell lineage. We showed that TRIM37 is expressed during mitosis of chondrocytes and directly impacted their proliferation. During the chondrocyte cell cycle, TRIM37 was present in both nucleus and cytoplasm. During M phase we observed an increase of the TRIM37-Tubulin co-localization in comparison with G1, S and G2 phases. TRIM37 knock down inhibited proliferation, together with cell cycle anomalies and increased autophagy, while overexpression accordingly enhanced cell proliferation. We demonstrated that microRNA-223 directly targets TRIM37, and suggest that miR-223 regulates TRIM37 gene expression during the cell cycle. In summary, our results give clues to explain why TRIM37 deficiency in chondrocytes impacts bone growth. Modulating TRIM37 using miR-223 could be an approach to increase chondrogenesis.

Knockdown of TRIM37 Promotes Apoptosis and Suppresses Tumor Growth in Gastric Cancer by Inactivation of the ERK1/2 Pathway

Objective

Gastric cancer (GC), a malignant tumor of the gastric mucosa, is the second leading cause of cancer deaths worldwide. Although the incidence and mortality of gastric cancer have been reduced in the US and elsewhere, it is still a major public health concern. In this study, we attempted to investigate the function of tripartite motif-containing protein 37 (TRIM37) in GC cell lines in order to propose a new therapy for GC.

Methods

The expression of TRIM37 in GC patients and cell lines was detected by immunohistochemistry, real-time PCR and Western blotting analysis. After TRIM37 knockdown or overexpression, the cell cycle, proliferation and apoptosis, as well as the expression of related proteins, were detected. In addition, in vivo experiments on nude mice were performed.

Results

We found that TRIM37 expression was significantly elevated in tumor tissues of GC patients and GC cell lines, and patients with high expression of TRIM37 had a poor prognosis. Knockdown of TRIM37 in GC cells significantly inhibited cell proliferation and cell cycle progression, promoted apoptosis, increased cleaved caspase 3 and decreased c-myc and phosphorylation of protein kinase 1/2 (p-ERK1/2). Effects of TRIM37 overexpression were opposite to that of TRIM37 knockdown and were potently attenuated by an ERK1/2 inhibitor. In addition, an ERK1/2 agonist increased TRIM37 and p-ERK1/2 in a dose-dependent manner, and TRIM37 knockdown potently attenuated EGF-induced cell proliferation and expression of TRIM37 and p-ERK1/2. Interestingly, we found that TRIM37 overexpression did not affect the mRNA level of dual-specificity phosphatase 6 (DUSP6), but reduced its protein level in GC cells. Co-immunoprecipitation (Co-IP) analyses revealed that TRIM37 interacted with DUSP6, and TRIM37 overexpression enhanced DUSP6 ubiquitination in GC cells. In vivo experiments on nude mice showed the inhibitory effect of TRIM37 knockdown on tumor growth.

Conclusion

These findings suggest that TRIM37 may act as an oncogene in the growth of GC cells and illustrate its potential function as a target in the treatment of GC.

Ginkgolide B protects human pulmonary alveolar epithelial A549 cells from lipopolysaccharide-induced inflammatory responses by reducing TRIM37-mediated NF-κB activation

The treatment options for acute stroke combined with pulmonary infection are limited. Clinically, there are several therapies to promote blood circulation and dissipate blood stasis; these treatment options include ginkgolide B (GB), which has PAF (platelet activating factor)-inhibiting effects. PAF-receptor (PAF-R) antagonists are used to treat a variety of inflammatory diseases; however, the potential of PAF-R antagonists as a treatment for lung infections remains unclear. The aim of the present study is to investigate the protective effect of GB on lipopolysaccharide-induced inflammatory responses in A549 human pulmonary alveolar epithelial cells (HPAEpiC) in vitro. Cell viability and apoptosis were measured by CCK-8 and flow cytometry. TRIM37, Caspase-3, and NF-κBp65 expression levels were measured by real-time PCR and Western blotting. The release of tumor necrosis factor-α and interleukin-1β was measured by ELISA. The data indicates that GB may reduce TRIM37 expression by antagonizing the PAF-R pathway, thereby inhibiting the activation of nuclear factor-κB and alleviating the inflammatory response of alveolar epithelial cells. This study is the first to provide insight into the therapeutic potential of GB and suggests that clinical application of GB in acute stroke combined with pulmonary inflammation may be efficacious.

Restriction of lung volumes but normal function of pulmonary tissue in mulibrey nanism

BACKGROUND

Mulibrey nanism (MUL) is a rare growth restriction disorder with multiple organ manifestations caused by genetic defects affecting the TRIM37 protein. A perimyocardial heart disease is the most serious manifestation. Many MUL children appear to suffer from airway obstruction related to infection or exercise, prompting use of inhaled therapies. Asthma medication is continued up to adolescence or even to adulthood due to persisting of symptoms. The pulmonary pathophysiology has previously not been evaluated in any MUL cohort.

METHODS

Thirty three finnish MUL patients (median age 20 years) were investigated with several lung function tests: spirometry with bronchodilatation test, single-breath diffusing capacity for carbon monoxide, single-breath lung volume measurements with helium dilution, and thoracic gas volume, airway resistance and specific conductance measurements with a body plethysmograph. As MUL typically affects body proportions, all variables were compared with reference values and with predicted values calculated from sitting height.

RESULTS

Total lung capacity and forced vital capacity were markedly reduced (total lung capacity [TLC] and forced vital capacity [FVC], P < .001, 51%-63% of predicted) and also forced expiratory volume in the first second was reduced (FEV1; P < .001, 47%-57%). No signs of airway obstruction was seen (normal FEV1/FVC and specific airway conductance SGaw). Diffusing capacity (DLCO) was decreased (P < .001, 60%-67%) but when related to alveolar volume it was increased (DLCO/VA, P < .001, 130%-148%). Bronchodilatation suggesting active asthma (FEV1 change ≥12% and ≥​​200 mL) was found only in one patient.

CONCLUSION

MUL patients typically have volume restriction of the lungs, but function of the pulmonary tissue remains intact. Evidence of asthma in lung function testing at adult age is rare.

Tripartite motif containing protein 37 involves in thrombin stimulated BV-2 microglial cell apoptosis and interleukin 1β release

Intracerebral hemorrhage (ICH) is the most common of stroke with high mortality and severe morbidity. Peroxisome proliferator-activated receptor gamma (PPARγ) plays a neuronprotective role in ICH. In the current study, TRIM37 mRNA expression in peripheral blood mononuclear cells (PBMCs) was found to be increased in ICH patients compared to that in healthy controls (n = 15). TRIM37 bound to PPARγ and enhanced its ubiquitination in mouse microglial BV-2 cell line. According to previous studies, thrombin is produced in the brain instantaneously after ICH and triggers the activation of microglia. Here, thrombin induced TRIM37 expression, cell apoptosis and interleukin-1β (IL-1β) release in BV-2 cells, while TRIM37 knockdown partially reversed the effects of thrombin on BV-2 cells. TRIM37 overexpression showed similar effects as thrombin on BV-2 cells, and PPARγ agonist rosiglitazone abolished the effects of TRIM37. In summary, TRIM37 involved in apoptosis and IL-1β release in BV-2 microglia by regulating PPARγ ubiquitination. The present data established a potential biological role of TRIM37 in ICH-induced brain damage and may provide insight into the development of therapy strategies for ICH.

TRIMming down to TRIM37: Relevance to Inflammation, Cardiovascular Disorders, and Cancer in MULIBREY Nanism

TRIpartite motif (TRIM) proteins are part of the largest subfamilies of E3 ligases that mediate the transfer of ubiquitin to substrate target proteins. In this review, we focus on TRIM37 in the normal cell and in pathological conditions, with an emphasis on the MULIBREY (MUscle-LIver-BRain-EYe) genetic disorder caused by TRIM37 mutations. TRIM37 is characterized by the presence of a RING domain, B-box motifs, and a coiled-coil region, and its C-terminal part includes the MATH domain specific to TRIM37. MULIBREY nanism is a rare autosomal recessive caused by TRIM37 mutations and characterized by severe pre- and postnatal growth failure. Constrictive pericarditis is the most serious anomaly of the disease and is present in about 20% of patients. The patients have a deregulation of glucose and lipid metabolism, including type 2 diabetes, fatty liver, and hypertension. Puzzlingly, MULIBREY patients, deficient for TRIM37, are plagued with numerous tumors. Among non-MULIBREY patients affected by cancer, a wide variety of cancers are associated with an overexpression of TRIM37. This suggests that normal cells need an optimal equilibrium in TRIM37 expression. Finding a way to keep that balance could lead to potential innovative drugs for MULIBREY nanism, including heart condition and carcinogenesis treatment.

TRIM37 targets AKT in the growth of lung cancer cells

Background

TRIM37 is an ubiquitin E3 ligase. Growing evidence has demonstrated the high value of TRIM37 as a potential biomarker for diagnosis of certain cancers. However, the biological function of TRIM37 in lung cancer is still unknown.

Materials and methods

In order to gain a deep insight into the function of TRIM37 in lung cancer cells, in the present study lentiviral vector was used to mediate RNA interference and overexpression of TRIM37 in lung cancer cells (H292, H358, and H1299). In addition, a specific AKT inhibitor LY294002 was utilized to examine the correlation between the expression of TRIM37 and AKT.

Results

TRIM37 acts as a positive regulator of cell proliferation in lung cancer cells. Moreover, cell apoptosis analyses showed the antiapoptosis function of TRIM37, which was mainly dependent on the regulation of BCL2 and BAX. Our results also indicated that AKT might be a target of TRIM37 in lung cancer cells.

Conclusion

This research not only helps in understanding the molecular mechanisms of TRIM37 in detail but also provides evidence to develop novel biomarkers for lung cancer diagnosis.

Tripartite motif-containing 37 (TRIM37) promotes the aggressiveness of non-small-cell lung cancer cells by activating the NF-κB pathway

Non-small-cell lung cancer (NSCLC), in which the NF-κB pathway is constitutively activated, is one of the most common malignancies. Herein, we identify an E3 ubiquitin ligase, tripartite motif-containing 37 (TRIM37), participating in the K63 polyubiquitination of TRAF2, which is a significant step in the activation of NF-κB signaling. Both the mRNA and the protein expression levels of TRIM37 were much higher in NSCLC cell lines and tissues than in normal bronchial epithelial cells and matched adjacent non-tumor tissues. TRIM37 expression correlated closely with clinical stage and poor survival in NSCLC. Overexpression of TRIM37 antagonized cisplatin-induced apoptosis, induced angiogenesis and proliferation, and increased the aggressiveness of NSCLC cells in vitro and in vivo, whereas inhibition of TRIM37 led to the opposite effects. Gene set enrichment analysis (GSEA) showed that TRIM37 expression significantly correlated with NF-κB signaling. Furthermore, we found that TRIM37 bound to TRAF2 and promoted K63-linked ubiquitination of TRAF2, sustaining the eventual activation of the NF-κB pathway. Mutation in the ring finger domain of TRIM37, a hallmark of E3 ubiquitin ligases, led to loss of the ability to promote K63 polyubiquitination of TRAF2 and activate NF-κB signaling. Taken together, our findings provide evidence that TRIM37 plays an important role in constitutive NF-κB pathway activation and could serve as a prognostic factor and therapeutic target in NSCLC. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

TRIM37 deficiency induces autophagy through deregulating the MTORC1-TFEB axis

TRIM37 gene mutations cause mulibrey (muscle-liver-brain-eye) nanism, a severe growth disorder with prenatal onset. Although TRIM37 depletion normally induces apoptosis, patients with TRIM37 mutations have a high risk of developing tumors, suggesting that there may be an alternative pro-survival mechanism for TRIM37-deficient tumor cells. We find that TRIM37 interacts with MTOR and RRAGB proteins, enhances the MTOR-RRAGB interaction and promotes lysosomal localization of MTOR, thereby activating amino acid-stimulated MTORC1 signaling. In response to loss of TRIM37 functions, phosphorylation of TFEB is significantly reduced, resulting in its translocation into the nucleus enabling its transcriptional activation of genes involved in lysosome biogenesis and macroautophagy/autophagy. The enhanced autophagy depends on the inhibition of MTORC1 signaling and may serve as an alternative mechanism to survive the loss of TRIM37 functions. Our study unveils a positive role of TRIM37 in regulating the MTORC1-TFEB axis and provides mechanistic insights into the pathogenesis of mulibrey nanism, as well as potential therapeutic treatment.

ABBREVIATIONS

ACTB: actin beta; ATG: autophagy related; CASP3: caspase3; CLEAR: coordinated lysosomal expression and regulation; CQ: chloroquine; CTS: cathepsin proteases; CTSL: cathepsin L; EIF4EBP1: eukaryotic translation initiation factor 4E binding protein 1; LAMP1: lysosomal associated membrane protein 1; LAMP2: lysosomal associated membrane protein 2; LMNB1: lamin B1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MTOR: mechanistic target of rapamycin kinase; MTORC1: MTOR complex 1; mulibrey: muscle-liver-brain-eye; NAC: N-acetyl-L-cysteine; PARP1: poly(ADP-ribose) polymerase 1; RAP2A: member of RAS oncogene family; RHEB: Ras homolog enriched in brain; ROS: reactive oxygen species; RPS6KB1: ribosomal protein S6 kinase B1; RRAGB: Ras related GTP binding B; SQSTM1: sequestosome 1; TFEB: transcription factor EB; TRIM37: tripartite motif containing 37.

TRIM37 inhibits PDGF-BB-induced proliferation and migration of airway smooth muscle cells

Tripartite motif 37 (TRIM37) belongs to the TRIM family of proteins and has been reported to be involved in the progression of asthma. However, the effects of TRIM37 on airway smooth muscle cells (ASMCs) proliferation and migration are still unknown. This study aimed to investigate the effects of TRIM37 on cell proliferation and migration in platelet-derived growth factor BB (PDGF-BB)-stimulated ASMCs, and the potential molecular mechanisms was also explored. Our data demonstrated that the expression of TRIM37 was significantly decreased in ASMCs stimulated with PDGF-BB. In addition, overexpression of TRIM37 efficiently suppressed PDGF-BB-induced ASMCs proliferation and migration. Furthermore, overexpression of TRIM37 obviously inhibited the protein expression levels of β-catenin, c-Myc and cyclinD1 in PDGF-BB-stimulated ASMCs. The Wnt/β-catenin pathway activator LiCl significantly reversed the inhibitory effects of TRIM37 on cell proliferation and migration in PDGF-BB-stimulated ASMCs. Taken together, these results demonstrate that TRIM37 inhibits the proliferation and invasion of ASMCs cultured with PDGF-BB through suppressing the Wnt/β-catenin signaling pathway.

Tripartite motif-containing protein 37 is overexpressed in human glioma and its downregulation inhibits human glioma cell growth in vitro

Glioma is one of the most malignant tumor types worldwide. Despite great efforts made in surgery, imaging, chemotherapy, and radiation, the overall prognosis for patients with glioma remains poor. The pathogenesis of glioma is an urgent problem that must be solved. Tripartite motif-containing protein 37 (TRIM37) is an E3 ubiquitin ligase that may be involved in the tumorigenesis of several types of cancer; however, its expression pattern and biological functions in glioma remain unknown. Our previous studies indicated that the expression levels of TRIM37 were upregulated in glioma samples and were associated with a higher glioma grade. The present study demonstrates that suppression of TRIM37 by RNA-mediated interference inhibits the growth of glioma cells in vitro, which is associated with induction of apoptosis and cell cycle arrest, and with inhibition of migration and invasion. These results provide insights into understanding the role of TRIM37 in regulating the biological behavior of glioma cells and may indicate TRIM37 as a candidate target for the treatment of glioma.

Knockdown of TRIM37 suppresses the proliferation, migration and invasion of glioma cells through the inactivation of PI3K/Akt signaling pathway

Tripartite motif 37 (TRIM37), a member of the TRIM protein family, was involved in the tumorigenesis of several types of cancer. However, the expression pattern and role of TRIM37 in glioma remain unclear. Therefore, the aim of the present study was to investigate the role of TRIM37 in glioma, and to determine the molecular mechanisms. Our results demonstrated that TRIM37 was highly expressed in human glioma tissues and cell liens. Additionally, knockdown of TRIM37 dramatically inhibited the proliferation, migration/invasion, and the epithelial-mesenchymal transition (EMT) phenotype in glioma cells. Furthermore, knockdown of TRIM37 significantly reduced the levels of phosphorylated PI3K and Akt in U87MG cells, and an activator of PI3K/Akt signaling (SC79) partly reversed the inhibitory effects of si-TRIM37 on glioma cell proliferation and migration. Taken together, our results demonstrated that TRIM37 functions as an oncogene in the development and progression of glioma. TRIM37 knockdown inhibited the proliferation and invasion of human glioma cells at least in part through the inactivation of PI3K/Akt signaling pathway.

Renal findings in patients with Mulibrey nanism

BACKGROUND

Mulibrey nanism (MUL) is a rare inherited disease caused by genetic defects affecting peroxisomal TRIM37 protein. MUL affects multiple organs, leading to growth retardation and early onset type 2 diabetes. We aimed to characterize the structure and function of kidneys and the urinary tract in a large cohort of Finnish MUL patients.

METHODS

Ultrasound, magnetic resonance imaging (MRI), and autopsy findings of the kidneys and urinary tract from 101 MUL patients were retrospectively analyzed. Renal function was examined using blood and urine biochemistry. Kidney pathology was assessed by histology and immunohistochemistry from biopsy and autopsy samples.

RESULTS

Structural anomalies of the kidneys and urinary tract were found in 13 % of MUL patients and renal tumors and macroscopic cystic lesions in 14 % and 43 % respectively. Overall, kidney histology was well preserved, but glomerular cysts with a wide Bowman's space were observed in most samples (87 %). Also, prominent and abundant blood vessels with thick walls were typically seen. Expression of endothelial cell markers and angiogenic growth factors PDGF-B and FGF1 (but not VEGF-A) was significantly increased in MUL kidneys. Markers of fibrosis and epithelial-mesenchymal transformation, α-SMA, and vimentin were moderately up-regulated. Despite radiological and histological changes, most MUL patients (age 0.2-51 years) had normal kidney function. However, 9 out of 36 patients (25 %) had hypertension and 6 out of 26 (23 %) had mildly decreased glomerular filtration.

CONCLUSIONS

Genetic defects in the TRIM37 gene lead to an increased risk for kidney anomalies, renal tumors, and solitary cysts in addition to glomerular cystic lesions, but not to progressive deterioration of renal function.

TRIM37 promoted the growth and migration of the pancreatic cancer cells

Increasing evidence indicated that tripartite motif containing 37 (TRIM37) was involved in the tumorigenesis of several cancer types. However, its expression pattern and biological functions in pancreatic ductal adenocarcinoma (PDAC) remained unknown. In this study, real-time PCR, Western blot and immunohistochemistry was performed to examine the expression of TRIM37 in the pancreatic cancerous tissues. Colony formation assay and cell migration assay were performed to study the functions of TRIM37 in pancreatic cancer cells. Dual-luciferase assay was performed to study the regulation of TRIM37 on beta-catenin/TCF signaling. It was found that the expression level of TRIM37 was significantly higher in pancreatic cancerous tissues compared with the adjacent normal tissues. Function analysis indicated that overexpression of TRIM37 promoted the growth and migration of the pancreatic cancer cells, while knocking down the expression of TRIM37 inhibited the growth and migration of the pancreatic cancer cells. The molecular mechanism study suggested that TRIM37 interacted with beta-catenin and activated the transcriptional activity of beta-catenin/TCF complex as well as the expression of its downstream target genes. Taken together, our study showed the oncogenic roles of TRIM37 in pancreatic cancer, and TRIM37 might be a promising target for pancreatic cancer treatment.