TRIM44 Promotes Colorectal Cancer Proliferation, Migration, and Invasion Through the Akt/mTOR Signaling Pathway

NAT10 Knockdown Improves Cisplatin Sensitivity in Non-Small Cell Lung Cancer by Inhibiting the TRIM44/PI3K/AKT Pathway

BACKGROUND

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related deaths worldwide, and cisplatin (DDP) resistance remains a significant challenge in NSCLC treatment.

METHODS

Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to analyze NAT10 and tripartite motif containing 44 (TRIM44) mRNA levels. Western blotting assay was used to detect protein expression. Cell viability was analyzed by a cell counting kit-8 assay. Cell proliferation, apoptosis, invasion, and stem-like traits were assessed using a 5-Ethynyl-2'-deoxyuridineassay, flow cytometry, Transwell invasion assay, and sphere formation assay, respectively. The association between NAT10 and TRIM44 was identified by an RNA immunoprecipitation assay. A xenograft mouse model was established to evaluate the effect of NAT10 silencing on DDP sensitivity in vivo.

RESULTS

NAT10 expression was upregulated in DDP-resistant NSCLC tissues and cells. NAT10 knockdown enhanced DDP sensitivity in DDP-resistant NSCLC cells, accompanied by decreased protein expression of multidrug resistance 1 (MDR1). The silencing of NAT10 also inhibited the proliferation, invasion, and stem-like traits of DDP-resistant NSCLC cells, while inducing cell apoptosis. However, NAT10 overexpression displayed the opposite effects. Moreover, NAT10 maintained TRIM44 mRNA stability in an ac4C-dependent manner. TRIM44 overexpression reversed the NAT10 knockdown-induced effects on DDP sensitivity and the malignant progression of NSCLC cells. In addition, NAT10 silencing inactivated the PI3K/AKT pathway by regulating TRIM44 in DDP-resistant NSCLC cells. The treatment of the PI3K/AKT pathway inhibitor, LY294002, mitigated the effects of TRIM44 overexpression on DDP sensitivity and NSCLC cell progression. Further, NAT10 knockdown improved the sensitivity of tumors to DDP in vivo.

CONCLUSION

NAT10 knockdown improved DDP sensitivity in NSCLC by inhibiting the TRIM44/PI3K/AKT pathway, which may have significant clinical implications for overcoming DDP resistance in NSCLC treatment.

TRIM44 facilitates aggressive behaviors in multiple myeloma through promoting ZEB1 deubiquitination

BACKGROUND

Tripartite motif-containing 44 (TRIM44) involves in various tumor development. This study investigated role of TRIM44 in multiple myeloma (MM).

MATERIALS AND METHODS

TRIM44 levels in bone marrow tissues and MM cell lines was detected by quantitative reverse transcription PCR (RT-qPCR). Cell viability, migration, and invasion of MM cells were evaluated under the interference of TRIM44 expression. The role of TRIM44 on regulating tumor growth in vivo was also investigated in subcutaneous tumor xenograft models. The protein interact between TRIM44 and Zinc Finger E-Box Binding Homeobox 1 (ZEB1) was also studied according IP followed by western blotting assay.

RESULTS

TRIM44 was all highly expressed in collected bone marrow tissues and MM cell lines. Cell viability, migration, and invasion of MM cells with low expression of TRIM44 was significantly inhibited. Over-expression of TRIM44 can down-regulate the ZEB1 ubiquitination to enhance the protein stability.

CONCLUSIONS

TRIM44 exerts as an oncogenic factor to induce the oncogenesis of MM by stabilizing ZEB1.

Exploring the Mechanisms, Biomarkers, and Therapeutic Targets of TRIM Family in Gastrointestinal Cancer

Gastrointestinal region (GI) cancers are closely linked to the ubiquitination system, with the E3 ubiquitin ligase playing a crucial role by targeting various substrates. As E3 ubiquitin ligases, proteins of tripartite motif (TRIM) family play a role in cancer signaling, development, apoptosis, and formation. These proteins regulate diverse biological activities and signaling pathways. This study comprehensively outlines the functions of TRIM proteins in gastrointestinal physiology, contributing to our knowledge of the molecular pathways involved in gastrointestinal tumors. Gastrointestinal region (GI) cancers are closely linked to the ubiquitination system, with the E3 ubiquitin ligase playing a crucial role by targeting various substrates.

Overexpression of TRIM44 mediates the NF-κB pathway to promote the progression of ovarian cancer

BACKGROUND

Ovarian cancer (OC) is the second most commonly seen cancer in the US, and patients with OC are commonly diagnosed in the advanced stage. Research into the molecular mechanisms and potential therapeutic targets of OC is becoming increasingly urgent. In our study, we worked to discover the role of TRIM44 in OC development.

OBJECTIVE

This study explored whether the overexpression of TRIM44 mediates the NF-kB pathway to promote the progression of OC.

METHODS

A TRIM44 overexpression model was constructed in SKOV3 cells, and the proliferation ability of the cells was detected using the CCK-8 assay. The migration healing ability of cells was detected using cell scratch assay. Cell migration and invasion were detected using Transwell nesting. TUNEL was applied to detect apoptosis, and ELISA and western blot were used to detect the expression of NF-κB signaling pathway proteins. The pathological changes of the tumor tissues were observed using HE staining in a mouse ovarian cancer xenograft model. Immunofluorescence double staining, RT-PCR, and western blot were used to determine the expression of relevant factors in tumour tissues.

RESULTS

TRIM44 overexpression promoted the proliferation, migration, and invasion of SKOV3 cells in vitro and inhibited apoptosis while enhancing the growth of tumours in vivo. TRIM44 regulated the NF-κB signaling pathway.

CONCLUSIONS

TRIM44 overexpression can regulate the NF-κB signaling pathway to promote the progression of OC, and TRIM44 may be a potential therapeutic target for OC.

Association of the TRIM family protein with survival outcomes and clinicopathological features in colorectal cancer: a systematic review and meta-analysis

BACKGROUND

The tripartite motif (TRIM) proteins have been reported to play crucial roles in various malignancies. However, the clinical significance of TRIM proteins in colorectal cancer (CRC) remains controversial. This study aimed to evaluate the association between TRIM proteins and the clinicopathological features and survival outcomes in patients with CRC.

METHODS

We performed a meta-analysis to investigate whether TRIM is a prognostic factor in CRC. PubMed, Embase, Web of Science, CNKI and Weipu databases were searched to identify eligible studies that evaluated the association between TRIM proteins and overall survival (OS), as well as the clinicopathological features of patients with CRC. Hazard ratios (HR) or odds ratios (OR) with 95% confidence interval (CI) were derived and pooled using a fixed-effects model.

RESULTS

From inception to March 2023, we extracted study characteristics and prognostic data for each identified study. Twelve studies enrolling 1608 patients were eligible for inclusion. Data on OS and recurrence-free survival (RFS) were available for 12 and 2 studies, respectively. The pooled analysis results showed a significant correlation between the elevated TRIM proteins and shorter OS (HR = 2.42, 95% CI: 1.96-2.99) and worse RFS (HR = 2.51, 95% CI: 1.78-3.54) in patients with CRC. The combined ORs indicated that TRIM protein over-expression was significantly associated with advanced TNM stage (OR = 2.26, 95% CI: 1.25-4.10), deep tumor invasion (OR = 2.01, 95% CI: 1.04-3.88), lymph node metastasis (OR = 2.99, 95% CI: 2.19-4.09) and perineural invasion (OR = 1.95, 95% CI: 1.18-3.23).

CONCLUSIONS

Our findings suggest that TRIM proteins can predict tumor progression and poor prognosis in CRC. Therefore, TRIM proteins may be promising therapeutic targets for patients with CRC.

TRIM44 aggravates cardiac fibrosis after myocardial infarction via TAK1 stabilization

Myocardial infarction (MI) is one of the most dangerous cardiovascular events. Cardiac fibrosis is a common pathological feature of remodeling after injury that is related to adverse clinical results with no effective treatment. Previous studies have confirmed that TRIM44, an E3 ligase, can promote the proliferation and migration of various tumor cells. However, the role of TRIM44 in cardiac fibrosis remains unknown. Models of TGF-β1 stimulation and MI-induced fibrosis were established to investigate the role and potential underlying mechanism of TRIM44 in cardiac fibrosis. The results showed that cardiac fibrosis was significantly inhibited after TRIM44 knockdown in a mouse model of MI, while it was enhanced when TRIM44 was overexpressed. Furthermore, in vitro studies showed that fibrosis markers were significantly reduced in cardiac fibroblasts (CFs) with TRIM44 knockdown, whereas TRIM44 overexpression promoted the expression of fibrosis markers. Mechanistically, TRIM44 maintains TAK1 stability by inhibiting the degradation of k48-linked polyubiquitination-mediated ubiquitination, thereby increasing phosphorylated TAK1 expression in the fibrotic environment and activating MAPKs to promote fibrosis. Pharmacological inhibition of TAK1 phosphorylation reversed the fibrogenic effects of TRIM44 overexpression. Combined, these results suggest that TRIM44 is a potential therapeutic target for cardiac fibrosis.

Cardiac-specific Trim44 knockout in rat attenuates isoproterenol-induced cardiac remodeling via inhibition of AKT/mTOR pathway

When pathological hypertrophy progresses to heart failure (HF), the prognosis is often very poor. Therefore, it is crucial to find new and effective intervention targets. Here, myocardium-specific Trim44 knockout rats were generated using CRISPR-Cas9 technology. Cardiac phenotypic observations revealed that Trim44 knockout affected cardiac morphology at baseline. Rats with Trim44 deficiency exhibited resistance to cardiac pathological changes in response to stimulation via isoproterenol (ISO) treatment, including improvement of cardiac remodeling and dysfunction by morphological and functional observations, reduced myocardial fibrosis and reduced expression of molecular markers of cardiac stress. Furthermore, signal transduction validation associated with growth and hypertrophy development in vivo and in vitro demonstrated that Trim44 deficiency inhibited the activation of signaling pathways involved in myocardial hypertrophy, especially response to pathological stress. In conclusion, the present study indicates that Trim44 knockout attenuates ISO-induced pathological cardiac remodeling through blocking the AKT/mTOR/GSK3β/P70S6K signaling pathway. This is the first study to demonstrate the function and importance of Trim44 in the heart at baseline and under pathological stress. Trim44 could be a novel therapeutic target for prevention of cardiac hypertrophy and HF.

Summary: This is the first study to demonstrate the function of Trim44 in the heart at baseline and under pathological stress. Trim44 could be a novel therapeutic target for prevention of cardiac hypertrophy.

The roles and targeting options of TRIM family proteins in tumor

Tripartite motif (TRIM) containing proteins are a class of E3 ubiquitin ligases, which are critically implicated in the occurrence and development of tumors. They can function through regulating various aspects of tumors, such as tumor proliferation, metastasis, apoptosis and the development of drug resistance during tumor therapy. Some members of TRIM family proteins can mediate protein ubiquitination and chromosome translocation via modulating several signaling pathways, like p53, NF-κB, AKT, MAPK, Wnt/β-catenin and other molecular regulatory mechanisms. The multi-domain nature/multi-functional biological role of TRIMs implies that blocking just one function or one domain might not be sufficient to obtain the desired therapeutic outcome, therefore, a detailed and systematic understanding of the biological functions of the individual domains of TRIMs is required. This review mainly described their roles and underlying mechanisms in tumorigenesis and progression, and it might shade light on a potential targeting strategy for TRIMs in tumor treatment, especially using PROTACs.

Non-coding RNAs and glioblastoma: Insight into their roles in metastasis

Glioma, also known as glioblastoma multiforme (GBM), is the most prevalent and most lethal primary brain tumor in adults. Gliomas are highly invasive tumors with the highest death rate among all primary brain malignancies. Metastasis occurs as the tumor cells spread from the site of origin to another site in the brain. Metastasis is a multifactorial process, which depends on alterations in metabolism, genetic mutations, and the cancer microenvironment. During recent years, the scientific study of non-coding RNAs (ncRNAs) has led to new insight into the molecular mechanisms involved in glioma. Many studies have reported that ncRNAs play major roles in many biological procedures connected with the development and progression of glioma. Long ncRNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs) are all types of ncRNAs, which are commonly dysregulated in GBM. Dysregulation of ncRNAs can facilitate the invasion and metastasis of glioma. The present review highlights some ncRNAs that have been associated with metastasis in GBM. miRNAs, circRNAs, and lncRNAs are discussed in detail with respect to their relevant signaling pathways involved in metastasis.

Knockdown of circRAD23B Exerts Antitumor Response in Colorectal Cancer via the Regulation of miR-1205/TRIM44 axis

BACKGROUND

Colorectal cancer (CRC) is a common cancer with high metastatic property. Circular RNAs (circRNAs) have important involvement in cancer processes. This study focused on the regulation of circRNA RAD23 homologue B (circRAD23B) in CRC.

METHODS

The levels of circRAD23B, microRNA-1205 (miR-1205), and tripartite motif-44 (TRIM44) were examined by quantitative real-time polymerase chain reaction (qRT-PCR). Functional analyses were performed by Cell Counting Kit-8 (CCK-8) for cell proliferation, flow cytometry for cell cycle or cell apoptosis, and transwell assay for cell migration and invasion. Western blot was administrated for protein detection. The interaction of targets was analyzed by dual-luciferase reporter and RNA pull-down assays. The in vivo experiment was conducted via xenograft tumor in mice.

RESULTS

We identified that circRAD23B was overexpressed in CRC tissues and cells. CRC cell proliferation, cell cycle progression, and cell metastasis were inhibited, while apoptosis was promoted by downregulating circRAD23B. Target analysis indicated that circRAD23B-targeted miR-1205 and TRIM44 were downstream genes of miR-1205. Moreover, the antitumor response of circRAD23B downregulation and miR-1205 overexpression was, respectively, achieved by increasing miR-1205 and decreasing TRIM44. CircRAD23B could regulate TRIM44 level by sponging miR-1205. In vivo, circRAD23B knockdown also reduced CRC tumorigenesis via the miR-1205/TRIM44 axis.

CONCLUSION

These results suggested that the inhibition of circRAD23B retarded the progression of CRC via acting on the miR-1205/TRIM44 axis. CircRAD23B might be a novel target in CRC treatment.

Paclitaxel resistance is mediated by NF-κB on mesenchymal primary breast cancer cells

Paclitaxel has been used widely to treat breast cancer and other types of cancer. However, resistance is a major cause of failure for treatment and results in cancer progression. The present study investigated the association between paclitaxel resistance and the mesenchymal phenotype, using a model of primary breast cancer cells and employing four different cultures, two with an epithelial phenotype (MBCDF and MBCD17) and two with a mesenchymal phenotype (MBCDF-D5 and MBCD3). Epithelial-mesenchymal markers were evaluated by western blotting; MBCDF and MBCD17 cells expressed E-cadherin, SNAIL, Slug, and Twist, low levels of N-cadherin, but not vimentin. MBCDF-D5 and MBCD3 cells expressed N-cadherin, vimentin, and higher levels of SNAIL, and low levels of E-cadherin, Slug, and Twist. Cell viability was evaluated using a crystal violet assay after paclitaxel treatment; primary breast cancer cells with mesenchymal phenotype were resistant to paclitaxel compared with the epithelial primary breast cancer cells. Furthermore, using western blotting, it was revealed that mesenchymal cells had elevated levels of nuclear factor-κΒ (NF-κB) p65 and IκB kinase (IKK). Additionally, it was demonstrated that paclitaxel-induced degradation of the inhibitor of NF-κB, activation of NF-κB in a dose-dependent manner, and Bcl-2 and Bcl-xL upregulation. Finally, employing western blotting and crystal violet assays, the effects of the proteasome inhibitor ALLN were assessed. ALLN inhibited paclitaxel-induced NF-κB activation and restored the sensitivity to paclitaxel. Together, these data suggest that targeting the NF-κB/IKK axis might be a promising strategy to overcome paclitaxel resistance.

circ_0030018 promotes glioma proliferation and metastasis

Background

Circular RNA (circRNA) plays an essential role in tumor progression, including glioma. circ_0030018 is a newly discovered circRNA that is highly expressed in glioma. However, its role and mechanism in glioma need to be further elucidated.

Methods

The expression of circ_0030018, microRNA (miR)-194-5p, and tripartite motif containing 44 (TRIM44) was examined using quantitative real-time PCR. Cell proliferation, migration, invasion, and apoptosis were determined using MTT assay, colony formation assay, transwell assay, and flow cytometry. Moreover, dual-luciferase reporter assay and RNA pull-down assay were used to verify the interactions among circ_0030018, miR-194-5p, and TRIM44. The protein expression of TRIM44 was assessed by western blot analysis. Animal experiments were conducted to explore the role of circ_0030018 in glioma tumor growth in vivo.

Results

circ_0030018 was overexpressed in glioma tissues and cells, and its silencing could inhibit glioma cell proliferation, migration, invasion, and accelerate apoptosis. miR-194-5p could be sponged by circ_0030018, and its overexpression could hinder the progression of glioma cells. Further experiments revealed that miR-194-5p inhibitor reversed the negative regulation of circ_0030018 knockdown on glioma cell progression. In addition, TRIM44 was a target of miR-194-5p, and its downregulation could repress glioma cell progression. Overexpressed TRIM44 reversed the inhibition effect of miR-194-5p on glioma cell progression. Animal experiments suggested that circ_0030018 knockdown could reduce glioma tumor growth through regulating miR-194-5p and TRIM44.

Conclusion

Our 8data showed that circ_0030018 enhanced glioma progression by sponging miR-194-5p to regulate TRIM44, indicating that circ_0030018 might be a potential treatment target for glioma.

Long non-coding RNA KCNQ1OT1 promotes proliferation, migration and invasion via targeting miR-134 in retinoblastoma

BACKGROUND

Long non-coding RNAs (lncRNAs) exert a significant role in carcinogenesis. lncRNA KCNQ1OT1 is detected in many tumors and is considered as an oncogene. The expression and mechanism of KCNQ1OT1 in retinoblastoma (Rb) are not clearly elucidated.

METHODS

KCNQ1OT1, miR-134 and TRIM44 mRNA expression were examined by a quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Proliferation, migration and invasion of Weri-Rb1 and Y79 cells were tested by cell counting kit-8, colony formation, scratch and transwell assays. Meanwhile, the regulatory relationships among KCNQ1OT1, miR-134 and TRIM44 were clarified by several biological experiments, including dual-luciferase reporter assay, RNA immunoprecipitation, subcellular distribution, qRT-PCR and western blotting.

RESULTS

lncRNA KCNQ1OT1 was up-regulated in Rb tissues and Rb cell lines. In addition, the expression of KCNQ1OT1 was negatively correlated with the disease-free survival rate of RB patients. Silencing KCNQ1OT1 could significantly inhibit the RB progression in vivo and in vitro. The analysis of the mechanism of KCNQ1OT1 showed that KCNQ1OT1 can sponge miR-134, and miR-134 may inhibit TRIM44 expression. Moreover, the rescue assays showed that KCNQ1OT1 promoted RB progression by regulating the miR-134/TRIM44 pathway.

CONCLUSIONS

The present study indicates that a new KCNQ1OT1/miR-134/TRIM44 pathway regulates Rb progression. It may be used as a potential prognostic marker for Rb.

TRIM Proteins in Colorectal Cancer: TRIM8 as a Promising Therapeutic Target in Chemo Resistance

Colorectal cancer (CRC) represents one of the most widespread forms of cancer in the population and, as all malignant tumors, often develops resistance to chemotherapies with consequent tumor growth and spreading leading to the patient’s premature death. For this reason, a great challenge is to identify new therapeutic targets, able to restore the drugs sensitivity of cancer cells. In this review, we discuss the role of TRIpartite Motifs (TRIM) proteins in cancers and in CRC chemoresistance, focusing on the tumor-suppressor role of TRIM8 protein in the reactivation of the CRC cells sensitivity to drugs currently used in the clinical practice. Since the restoration of TRIM8 protein levels in CRC cells recovers chemotherapy response, it may represent a new promising therapeutic target in the treatment of CRC.

Circ_0056285 Regulates Proliferation, Apoptosis and Glycolysis of Osteosarcoma Cells via miR-1244/TRIM44 Axis

Background

Osteosarcoma (OS) is a common malignant bone cancer that occurs in adolescents and children. Circular RNAs (circRNAs) are important regulators of tumorigenesis and development. This study aimed to explore the role and molecular basis of circ_0056285 in OS.

Methods

The levels of circ_0056285, miR-1244 and tripartite motif containing 44 (TRIM44) were determined by quantitative real-time polymerase chain reaction or Western blot assay. Cell proliferation was evaluated by Cell Counting Kit-8 (CCK-8) assay and colony formation assay. Cell apoptosis was assessed by flow cytometry and caspase 3and caspase 9 activity assay kits. Glucose uptake, lactate product and ATP level were examined using commercial kits. Hexokinase II (HK2) and lactate dehydrogenase A (LDHA) levels were measured by Western blot assay. The interaction among circ_0056285, miR-1244 and TRIM44 was confirmed by dual-luciferase reporter assay, RNA immunoprecipitation assay or RNA pull-down assay. Xenograft experiment was conducted to explore tumor growth in vivo. Exosomes were identified by transmission electron microscope (TEM), nanoparticle tracking analysis (NTA) and Western blot. The diagnostic value of exosomal circ_0056285 was evaluated by receiver operating characteristic (ROC) curve.

Results

Circ_0056285 and TRIM44 were up-regulated, and miR-1244 was down-regulated in OS tissues and cells. Circ_0056285 silencing inhibited proliferation and glycolysis and promoted apoptosis in OS cells. Also, circ_0056285 knockdown hindered proliferation and accelerated apoptosis in OS cells by regulating miR-1244/TRIM44 axis. Circ_0056285 depletion impeded tumor growth in vivo. Furthermore, ROC curve showed that circ_0056285 might be a diagnostic biomarker in OS.

Conclusion

Circ_0056285 facilitated OS progression by sponging miR-1244 and increasing TRIM44 expression, providing a promising therapeutic target for OS.

Inhibition of SPATS2 Suppresses Proliferation and Invasion of Hepatocellular Carcinoma Cells through TRIM44-STAT3 Signaling Pathway

Hepatocellular carcinoma (HCC) is a major global health burden and its treatment options are limited. Spermatogenesis associated serine rich 2(SPATS2), a recent defined oncogene, was found to be a prognostic biomarker in HCC. However, the explicit mechanism underlying SPATS2 was urged to be elucidated. In vitro, knockdown of SPATS2 hampered the proliferation, invasion and migration of HCC cells. Moreover, phosphorylation of signal transducer and activator of transcription 3 (STAT3) and its downstream oncogenes were dramatically suppressed by SPATS2 knockdown. In addition, tripartite motif containing 44 (TRIM44) was found to be positively associated with SPATS2 in TCGA and declined after SPATS2 knockdown in HCC cells. Overexpression of TRIM44 rescued the effect of SPATS2 silencing on p-STAT3 and its downstream oncogenes. In vivo, SPATS2 silencing was confirmed to impede HCC tumor development in nude mice. In our own cohort containing 112 HCC patients, high SPATS2 protein level is indicative of an unfavorable clinicopathological feature and poor prognosis and could serve as an independent risk factor. Collectively, the present study is the first to propose the mechanism of significance of SPATS2-TRIM44-p-STAT3 in HCC and provide a new theoretical basis for targeted therapy.

The Novel Target of Colorectal Carcinoma: TRIM44 Regulates Cell Migration and Invasion via Activation of CXCR4/NF-κB Signaling

Tripartite motif containing 44 (TRIM44) has been reported to regulate various biological effects in malignant cancers and matrix Metalloproteinases has been demonstrated to be associated with cancer cell migration and invasion. Nonetheless, the expression and molecular mechanism of TRIM44 in colorectal cancer (CRC) remain rarely known. TRIM44 was overexpressed or knocked down in CRC cells. Subsequently, the effects of TRIM44 on cell migration and invasion as well as underlying molecular mechanisms were detected. Data showed that TRIM44 was highly expressed in CRC cell lines. Downregulation of TRIM44 inhibited the cell viability, migration, and invasion in SW-480 cells. In addition, overexpression of TRIM44 enhanced the expression of NF-κB and CXCR4, and enhanced the binding between NF-κB and CXCR4 promoter region. In summarize, TRIM44 may serve as a potential target for CRC diagnosis and progression.

Multifaceted Roles of TRIM Proteins in Colorectal Carcinoma

Colorectal cancer (CRC) is one of the most frequently diagnosed tumor in humans and one of the most common causes of cancer-related death worldwide. The pathogenesis of CRC follows a multistage process which together with somatic gene mutations is mainly attributed to the dysregulation of signaling pathways critically involved in the maintenance of homeostasis of epithelial integrity in the intestine. A growing number of studies has highlighted the critical impact of members of the tripartite motif (TRIM) protein family on most types of human malignancies including CRC. In accordance, abundant expression of many TRIM proteins has been observed in CRC tissues and is frequently correlating with poor survival of patients. Notably, some TRIM members can act as tumor suppressors depending on the context and the type of cancer which has been assessed. Mechanistically, most cancer-related TRIMs have a critical impact on cell cycle control, apoptosis, epithelial–mesenchymal transition (EMT), metastasis, and inflammation mainly through directly interfering with diverse oncogenic signaling pathways. In addition, some recent publications have emphasized the emerging role of some TRIM members to act as transcription factors and RNA-stabilizing factors thus adding a further level of complexity to the pleiotropic biological activities of TRIM proteins. The current review focuses on oncogenic signaling processes targeted by different TRIMs and their particular role in the development of CRC. A better understanding of the crosstalk of TRIMs with these signaling pathways relevant for CRC development is an important prerequisite for the validation of TRIM proteins as novel biomarkers and as potential targets of future therapies for CRC.

MicroRNA-623 Inhibits Epithelial-Mesenchymal Transition to Attenuate Glioma Proliferation by Targeting TRIM44

Objective

Glioma has the highest incidence among the different tumor types within the nervous system, accounting for about 40% of them. Malignant glioma has a high invasion and metastasis rate, which leads to the poor prognosis of patients. By targeting specific genes, microRNAs serve as key regulators in the epithelial–mesenchymal transformation (EMT) process, which could provide new insights into the treatment of glioblastomas (GBM). The detailed molecular role that miR-623 plays in GBM still remains unclear.

Materials and Methods

The level of miR-623 in GBM cells was evaluated by RT-PCR. The function of miR-623 overexpression on GBM cell proliferation, migration, and invasion was assessed by MTS, Transwell analysis, and colony formation assay. In addition, a mouse subcutaneous xenograft model was used to study in vivo effects. The binding between miR-623 and TRIM44 was verified by a dual-luciferase reporter assay and the regulatory function of miR-623 on EMT markers was evaluated using Western blot.

Results

The expression of miR-623 was repressed in the GBM cancer cell lines. MiR-623 overexpression or TRIM44 knockdown attenuated the proliferation, migration, and invasion of GBM cell lines. TRIM44 could facilitate the reverse suppression of EMT and miR-623 in GBM progression. MiR-623 was found to inhibit TRIM44 expression by directly binding to its 3ʹUTR. In addition, systemic delivery of miR-623 mimic reduced tumor growth and inhibited TRIM44 protein expression in tumor-bearing nude mice. Furthermore, our findings indicated that miR-623 overexpression or TRIM44 down-regulation impeded the proliferation and migratory ability of LN229 and U251MG glioma cells, and miR-623 attenuates TRIM44-induced EMT by directly targeting the 3ʹUTR of TRIM44, which could serve as preliminary research to identify potential therapeutic targets for future treatment of GBM.

Conclusion

Overall, microRNA-623 inhibits epithelial–mesenchymal transition to attenuate glioma proliferation by targeting TRIM44.

PCYT1A suppresses proliferation and migration via inhibiting mTORC1 pathway in lung adenocarcinoma

Lung cancer is one of most common malignant cancer worldwide. It is emerging that PCYT1A, a rate-limiting enzyme required for the biosynthesis of phosphatidylcholine, is associated with cancer progression. However, the biological functions and underlying molecular mechanisms of PCYT1A in lung adenocarcinoma is still unknown. Here we found that PCYT1A suppressed lung adenocarcinoma cancer cell proliferation and migration. Mechanically, PCYT1A served as a novel negative regulator of mTORC1 signaling. PCYT1A knockdown enhanced the malignant proliferation and migration of lung adenocarcinoma cells by activating mTORC1. The promoting effects of PCYT1A silencing on cell proliferation and migration could be abolished when mTORC1 signaling was inhibited by rapamycin or RAPTOR depletion. Importantly, PCYT1A high expression predicted longer survival of lung cancer patients. The expression of PCYT1A was also negatively correlated with mTORC1 activation in the clinical lung cancer samples. We therefore reveal that PCYT1A suppresses proliferation and migration by inhibiting the mTORC1 signaling pathway in lung adenocarcinoma. PCYT1A shows as a potential promising biomarker in lung adenocarcinoma.