Hsa_circ_0026134 expression promoted TRIM25- and IGF2BP3-mediated hepatocellular carcinoma cell proliferation and invasion via sponging miR-127-5p

Establishment of a circRNA-regulated E3 ubiquitin ligase signature and nomogram to predict immunotherapeutic efficacy and prognosis in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a common type of malignant tumor where the prognosis is dismal. Circular RNA (CircRNA) is a novel RNA that regulates downstream gene transcription and translation to influence the progression of HCC. However, the regulatory relationship that exists between E3 ligases, which is a class of post-translational modifying proteins, and circRNA remains unclear.

METHODS

Based on the E3 ubiquitin ligase in the competitive endogenous RNA (ceRNA) network, a circRNA-regulated E3 ubiquitin ligase signature (CRE3UL) was developed. A CRE3UL signature was created using the least absolute shrinkage and selection operator (Lasso) and Cox regression analysis and merged it with clinicopathologic characteristics to generate a nomogram for prognosis prediction. The pRRophetic algorithm was utilized and immunological checkpoints were analyzed to compare the responses of patients in the high-risk group (HRG) and low-risk group (LRG) to targeted therapy and immunotherapy. Finally, experimental research will further elucidate the relationship between E3 ubiquitin ligase signature and HCC.

RESULTS

HRG patients were found to have a worse prognosis than LRG patients. Furthermore, significant variations in prognosis were observed among different subgroups based on various clinical characteristics. The CRE3UL signature was identified as being an independent prognostic indicator. The nomogram that combined clinical characteristics and the CRE3UL signature was found to accurately predict the prognosis of HCC patients and demonstrated greater clinical utility than the current TNM staging approach. According to anticancer medication sensitivity predictions, the tumors of HRG patients were more responsive to gefitinib and nilotinib. From immune-checkpoint markers analysis, immunotherapy was identified as being more probable to assist those in the HRG.

CONCLUSIONS

We found a significant correlation between the CRE3UL signature and the tumor microenvironment, enabling precise prognosis prediction for HCC patients. Additionally, a nomogram was developed that performs well in predicting the overall survival (OS) of HCC patients. This provides valuable guidance for clinicians in devising specific personalized treatment strategies.

Epigenetic regulation of hepatocellular carcinoma progression: MicroRNAs as therapeutic, diagnostic and prognostic factors

Hepatocellular carcinoma (HCC), a significant challenge for public healthcare systems in developed Western countries including the USA, Canada, and the UK, is influenced by different risk factors including hepatitis virus infections, alcoholism, and smoking. The disruption in the balance of microRNAs (miRNAs) plays a vital function in tumorigenesis, given their function as regulators in numerous signaling networks. These miRNAs, which are mature and active in the cytoplasm, work by reducing the expression of target genes through their impact on mRNAs. MiRNAs are particularly significant in HCC as they regulate key aspects of the tumor, like proliferation and invasion. Additionally, during treatment phases such as chemotherapy and radiotherapy, the levels of miRNAs are key determinants. Pre-clinical experiments have demonstrated that altered miRNA expression contributes to HCC development, metastasis, drug resistance, and radio-resistance, highlighting related molecular pathways and processes like MMPs, EMT, apoptosis, and autophagy. Furthermore, the regulatory role of miRNAs in HCC extends beyond their immediate function, as they are also influenced by other epigenetic factors like lncRNAs and circular RNAs (circRNAs), as discussed in recent reviews. Applying these discoveries in predicting the prognosis of HCC could mark a significant advancement in the therapy of this disease.

TRIM25 negatively regulates IKKε-mediated interferon signaling in black carp

IKKε plays an important role in the activation of IRF3/IRF7 and the production of interferon (IFN), however, its regulation remains obscure in human. E3 ligase TRIM25 has been reported to manipulate the K63-linked ubiquitination of RIG-I, leading to the activation of RIG-I/IFN signaling. To elucidate the role of TRIM25 in teleost, a TRIM25 homolog (bcTRIM25) was cloned and characterized from black carp (Mylopharyngodon piceus). bcTRIM25 contains 653 amino acids, possessing conservative RING, B-box and SPRY domain, which is highly expressed in muscle, spleen and skin. bcTRIM25 knock-down enhanced the antiviral ability of host cells. bcTRIM25 over-expression alone in EPC cells attenuated bcIFNa promoter transcription in the reporter assays and impeded PKR and MX1 expression in qRT-PCR. Interestingly, co-IP assays indicated that bcTRIM25 interacted with bcIKKε and the induced bcIFNa promoter transcription by bcIKKε was notably hindered by bcTRIM25. Furthermore, bcIKKε-induced expression of interferon stimulated genes (ISGs) and antiviral activity were dampened by bcTRIM25. Further exploration showed that bcTRIM25 visibly enhanced the ubiquitination of bcIKKε but significantly attenuated the phosphorylation of bcIKKε. Thus, our data demonstrate for the first time in vertebrate that TRIM25 negatively regulates IKKε through enhancing its ubiquitination, which sheds a light on the regulation of IKKε/IFN signaling.

Deciphering roles of TRIMs as promising targets in hepatocellular carcinoma: current advances and future directions

Tripartite motif (TRIM) family is assigned to RING-finger-containing ligases harboring the largest number of proteins in E3 ubiquitin ligating enzymes. E3 ubiquitin ligases target the specific substrate for proteasomal degradation via the ubiquitin-proteasome system (UPS), which seems to be a more effective and direct strategy for tumor therapy. Recent advances have demonstrated that TRIM genes associate with the occurrence and progression of hepatocellular carcinoma (HCC). TRIMs trigger or inhibit multiple biological activities like proliferation, apoptosis, metastasis, ferroptosis and autophagy in HCC dependent on its highly conserved yet diverse structures. Remarkably, autophagy is another proteolytic pathway for intracellular protein degradation and TRIM proteins may help to delineate the interaction between the two proteolytic systems. In depth research on the precise molecular mechanisms of TRIM family will allow for targeting TRIM in HCC treatment. We also highlight several potential directions warranted further development associated with TRIM family to provide bright insight into its translational values in hepatocellular carcinoma.

The G allele of SNP rs3922 reduces the binding affinity between IGF2BP3 and CXCR5 correlating with a lower antibody production

Effective vaccines that function through humoral immunity seek to produce high-affinity antibodies. Our previous research identified the single-nucleotide polymorphism rs3922G in the 3'UTR of CXCR5 as being associated with nonresponsiveness to the hepatitis B vaccine. The differential expression of CXCR5 between the dark zone (DZ) and light zone (LZ) is critical for organizing the functional structure of the germinal center (GC). In this study, we report that the RNA-binding protein IGF2BP3 can bind to CXCR5 mRNA containing the rs3922 variant to promote its degradation via the nonsense-mediated mRNA decay pathway. Deficiency of IGF2BP3 leads to increased CXCR5 expression, which results in the disappearance of CXCR5 differential expression between DZ and LZ, disorganized GCs, aberrant somatic hypermutations, and reduced production of high-affinity antibodies. Furthermore, the affinity of IGF2BP3 for the rs3922G-containing sequence is lower than that for the rs3922A counterpart, which may explain the nonresponsiveness to the hepatitis B vaccination. Together, our findings suggest that IGF2BP3 plays a crucial role in the production of high-affinity antibodies in the GC by binding to the rs3922-containing sequence to regulate CXCR5 expression.

The Long Non-Coding RNA AC006329.1 Facilitates Hepatocellular Carcinoma Progression and Metastasis by Regulating miR-127-5p/SHC3/ERK Axis

Purpose

Hepatocellular carcinoma(HCC) is the most common type of liver cancer and the sixth largest common cancer worldwide. Although surgical resection, hepatic arterial chemoembolization, targeted drugs and immunotherapy are currently available, the mortality of advanced patients remains high. Therefore, new therapeutic targets are urgently needed. In recent years, many studies have found that The long non-coding RNA(lncRNA) has multiple functions in human tumors, including participating in epigenetic, transcriptional, post-transcriptional and translational regulation, and is closely related to the progression of HCC. The purpose of this study was to investigate the role of AC006329.1 in HCC progression and provide theoretical guidance for finding new targets.

Patients and Methods

AC006329.1 was screened out by transcriptome sequencing and quantitative real-time polymerase chain reaction (qRT-PCR). Then a series of functional tests in vivo and in vitro were conducted to investigate the effects of AC006329.1 on HCC progression and metastasis. Epithelial-mesenchymal transformation (EMT) of HCC was detected by Western blot and immunofluorescence staining. The targeted miRNA and downstream gene of AC006329.1 were predicted by databases and the pathway regulation axis eventually validated by dual luciferase reporter assays, qRT-PCR and WB.

Results

AC006329.1 was found high expressed in HCC tissues and cell lines by qRT-PCR. The prognosis of HCC patients with high expressed AC006329.1 was poor. In vitro and in vivo, overexpression of AC006329.1 can promote the progression, metastasis and EMT of HCC by acting as a sponge of miR-127-5p to increase the expression of SHC3. In addition, up-regulation of miR-127-5p or knockdown of SHC3 can both reverse the promoting effects of AC006329.1 on progression, metastasis and EMT of HCC. Finally, WB and qRT-PCR analysis was discovered that AC006329.1 can facilitate HCC progression, EMT and metastasis by competitively inhibiting miR-127-5p to activate SHC3/ERK signaling pathway.

Conclusion

These above experimental results confirmed that AC006329.1 can facilitate HCC progression, EMT and metastasis by acting as a competing endogenous RNA (ceRNA) to inhibit miR-127-5p and activate SHC3/ERK signaling pathway.

Epigenetic modification of m6A regulator proteins in cancer

Divergent N6-methyladenosine (m6A) modifications are dynamic and reversible posttranscriptional RNA modifications that are mediated by m6A regulators or m6A RNA methylation regulators, i.e., methyltransferases ("writers"), demethylases ("erasers"), and m6A-binding proteins ("readers"). Aberrant m6A modifications are associated with cancer occurrence, development, progression, and prognosis. Numerous studies have established that aberrant m6A regulators function as either tumor suppressors or oncogenes in multiple tumor types. However, the functions and mechanisms of m6A regulators in cancer remain largely elusive and should be explored. Emerging studies suggest that m6A regulators can be modulated by epigenetic modifications, namely, ubiquitination, SUMOylation, acetylation, methylation, phosphorylation, O-GlcNAcylation, ISGylation, and lactylation or via noncoding RNA action, in cancer. This review summarizes the current roles of m6A regulators in cancer. The roles and mechanisms for epigenetic modification of m6A regulators in cancer genesis are segregated. The review will improve the understanding of the epigenetic regulatory mechanisms of m6A regulators.

Targeting IGF2BP3 in Cancer

RNA-binding proteins (RBPs) can regulate multiple pathways by binding to RNAs, playing a variety of functions, such as localization, stability, and immunity. In recent years, with the development of technology, researchers have discovered that RBPs play a key role in the N6-methyladenosine (m6A) modification process. M6A methylation is the most abundant form of RNA modification in eukaryotes, which is defined as methylation on the sixth N atom of adenine in RNA. Insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) is one of the components of m6A binding proteins, which plays an important role in decoding m6A marks and performing various biological functions. IGF2BP3 is abnormally expressed in many human cancers, often associated with poor prognosis. Here, we summarize the physiological role of IGF2BP3 in organisms and describe its role and mechanism in tumors. These data suggest that IGF2BP3 may be a valuable therapeutic target and prognostic marker in the future.

ANXA10 is a prognostic biomarker and suppressor of hepatocellular carcinoma: a bioinformatics analysis and experimental validation

Liver hepatocellular carcinoma (LIHC) is one of the main cancers worldwide and has high morbidity and mortality rates. Although previous studies have shown that ANXA10 is expressed at low levels in LIHC tumor tissues, the biological function of ANXA10 in LIHC is still unclear. Therefore, we utilized TCGA, TIMER, GEPIA2, TISIDB, LinkedOmics, ssGSEA algorithms and CIBERSORT methodology to preliminarily evaluate the potential mechanism of ANXA10 in LIHC. In vitro experiments were used to further verify some functions of ANXA10. Consequently, we found that ANXA10 mRNA/protein expression was downregulated in LIHC tissue compared to normal tissue. ANXA10 was significantly linked with clinicopathological features, immunocytes, multiple cancer-related pathways, m6A modification and a ceRNA network. A three-gene prognostic signature rooted in ANXA10-related immunomodulators was determined and found to be an independent prognostic predictor. A nomogram was constructed to predict survival with good accuracy. Additionally, in vitro trials revealed that ANXA10 upregulation inhibited LIHC cell proliferation and migration. This study reveals that ANXA10 may serve as a prognostic marker and promising therapeutic target in LIHC clinical practice through various biologic functions.

TRIM proteins in hepatocellular carcinoma

The tripartite motif (TRIM) protein family is a highly conserved group of E3 ligases with 77 members known in the human, most of which consist of a RING-finger domain, one or two B-box domains, and a coiled-coil domain. Generally, TRIM proteins function as E3 ligases to facilitate specific proteasomal degradation of target proteins. In addition, E3 ligase independent functions of TRIM protein were also reported. In hepatocellular carcinoma, expressions of TRIM proteins are both regulated by genetic and epigenetic mechanisms. TRIM proteins regulate multiple biological activities and signaling cascades. And TRIM proteins influence hallmarks of HCC. This review systematically demonstrates the versatile roles of TRIM proteins in HCC and helps us better understand the molecular mechanism of the development and progression of HCC.

miR-127-5p Targets JAM3 to Regulate Ferroptosis, Proliferation, and Metastasis in Malignant Meningioma Cells

Objective

Meningiomas are one of the most common primary tumors of the central nervous system. Most of them are benign and can be cured by surgery, while a few meningiomas are malignant. Ferroptosis gene characteristics might be associated with drug therapy and survival in patients with clinically aggressive, unresectable meningiomas. This study explored the mechanism of differentially expressed miRNAs and ferroptosis in meningioma to provide a new reference to treat meningioma.

Methods

Bioinformatics analysis of differential miRNA profiles and functions in patients with meningioma was performed. The contents of lactate dehydrogenase (LDH), malondialdehyde (MDA), and Fe²⁺ were determined. Reactive oxygen species (ROS) values, as well as cell cycle changes, were analyzed by flow cytometry. The targets of miR-127-5p and JAM3 were detected by dual luciferase assays. Cell counting kit-8 (CCK8) and Transwell assays were used to analyze cell activity. Ki67 expression was analyzed by immunohistochemistry. Expression levels of miR-127-5p and JAM3 were analyzed by RT-qPCR. GPX4 expression was quantified by western blotting.

Results

miR-127-5p was expressed at low levels in IOMM-Lee cells, while JAM3 was highly expressed in IOMM-Lee cells. A dual luciferase assay demonstrated that miR-127-5p could target JAM3. Upregulation of miR-127-5p in IOMM-Lee cells resulted in cell cycle arrest and inhibition of cell activity. Upregulation of miR-127-5p increased LDH, MDA, and ROS levels and Fe²⁺ content and inhibited the expression of GPX4 protein. Upregulation of JAM3 reversed the results of miR-127-5p upregulation.

Conclusion

miR-127-5p regulated meningioma formation and ferroptosis through JAM3, providing insights for the development of new treatments for meningioma.

Hsa_circ_0006732 regulates colorectal cancer cell proliferation, invasion and EMT by miR-127-5p/RAB3D axis

Colorectal cancer (CRC) remains a malignancy tumor with high metastasis and poor prognosis. We aimed to explore the effect of circular RNA (circRNA) hsa_circ_0006732 in the progression of CRC. Hsa_circ_0006732 expression in CRC tissues and cell lines were detected using qRT-PCR. The relationship between hsa_circ_0006732 expression and clinicopathologic characteristics of patients with CRC was analyzed. Loss-of-function assay was conducted to determine the regulatory effect of hsa_circ_0006732 on CRC cell proliferation, migration and invasion by using the CCK-8, wound-healing assay and transwell assays. Protein expression changes on epithelial mesenchymal transition (EMT)-related factors were detected by western blotting. The downstream signaling pathway was investigated by bioinformatics, dual-luciferase reporter assay. Rescue assay was further examined for prediction validation. It was found that hsa_circ_0006732 was highly expressed in CRC tissues and cell lines. Downregulation of hsa_circ_0006732 suppressed the proliferation, migration, invasion and EMT of CRC cells. Further mechanistic investigations proved that hsa_circ_0006732 functioned as a competitive endogenous RNA (ceRNA) by directly sponging of miR-127-3p, which further affected the expression of Ras-related protein Rab-3D (Rab3D). Taken together, these findings indicated that hsa_circ_0006732 might be an oncogene in CRC through the regulation of the miR-127-5p/RAB3D axis. Thus, hsa_circ_0006732 might serve as a potential therapeutic target for the treatment of CRC.

hsa_circ_0000285 facilitates thyroid cancer progression by regulating miR-127-5p/CDH2

Thyroid cancer (THCA) is a leading endocrine cancer and becomes the fifth most commonly diagnosed malignancy in females. It is confirmed that circular RNAs (circRNAs) perform regulatory potencies in the pathological progress of THCA. Our purpose was to certify the trait of hsa_circ_0000285 (circ_0000285) and investigate its modulatory mechanism in THCA progression. We identified the expression profile of hsa_circ_0000285 in THCA by conducting qRT-PCR assay. Therewith, the potential of hsa_circ_0000285 in THCA development was determined with a set of functional experiments, including CCK-8, wound healing assay, Western blot, and xenograft model. The molecular mechanism underlying hsa_circ_0000285 was investigated with bioinformatic analysis, RIP and dual-luciferase reporter experiments. As opposed to normal samples and cells, hsa_circ_0000285 level was overtly increased in THCA specimens and cells. The downregulation of hsa_circ_0000285 weakened the proliferative and migratory capacity of THCA cells and promoted cell apoptosis. In addition, hsa_circ_0000285 silence suppressed the tumor growth of xenograft model mice in vivo. Notably, we demonstrated that hsa_circ_0000285 might target miR-127-5p/CDH2 axis in THCA. Afterward, our findings manifested that miR-127-5p attenuation blocked the function of hsa_circ_0000285 depletion in THCA cells. In the final step, CDH2 was proven to mediate the repressive potency of miR-127-5p in the malignant behaviors of THCA. Mechanistically, hsa_circ_0000285 induced the development of THCA via functioning as a competing endogenous RNA (ceRNA) of miR-127-5p to enhance CDH2 expression, which provided a new perspective for THCA therapy.

Circular RNA Circ_0000098 Elevates ALX4 Expression via Adsorbing miR-1204 to Inhibit the Progression of Hepatocellular Carcinoma

Background

Circular RNAs (CircRNAs) feature prominently in the progression of various cancers. However, the biological functions of many circRNAs in hepatocellular carcinoma (HCC) are far from fully clarified. This work is performed to decipher the function of circ_0000098 (circSLC30A7) in modulating the progression of HCC and its molecular mechanism.

Methods

Microarray data (GSE97332) were available from the Gene Expression Omnibus (GEO) database, and circRNA differentially expressed in HCC tissues was screened out by GEO2R tool. Circ_0000098, microRNA-1204 (miR-1204), and aristaless-like homeobox-4 (ALX4) mRNA expressions were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell counting kit-8 (CCK-8), scratch wound healing, and Transwell assays were adopted to determine proliferation, migration, and invasion of HCC cells. ALX4 protein, E-cadherin, N-cadherin, and Vimentin expressions were evaluated by Western blot. In addition, the targeting relationship between miR-1204 and circ_0000098 or ALX4 was studied with dual-luciferase reporter assay and RIP assay.

Results

Circ_0000098 expression level was markedly declined in HCC tissues and cells, and its underexpression was associated with larger tumor size of HCC patients. Knocking down circ_0000098 observably promoted the multiplication, migration, invasion, and epithelial-mesenchymal transition (EMT) of Huh7 and SMMC-7721 cells. Additionally, circ_0000098 was mainly distributed in the cytoplasm of HCC cells, and up-regulated ALX4 expression through competitively decoying miR-1204.

Conclusion

Circ_0000098, as a competitive endogenous RNA (ceRNA) of miR-1204, upregulates ALX4 expression and suppresses the growth, migration, invasion, and EMT of HCC cells.

CircRNA Circ-CCND1 Aggravates Hepatocellular Carcinoma Tumorigenesis by Regulating the miR-497-5p/HMGA2 Axis

Circular RNAs (circRNAs) are key regulators in hepatocellular carcinoma (HCC) tumorigenesis and development, yet it is unclear whether circ-CCND1 participates in regulating HCC progression. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed for detecting the expressions of circ-CCND1, microRNA (miR) -497-5p, and high mobility group AT-hook 2 (HMGA2) mRNA in HCC tissues and cell lines. Subcellular fractionation assay was used to analyze the localization of circ-CCND1 in HCC cell lines. Loss-of-function experiments were conducted to examine the effects of circ-CCND1 on HCC cell proliferation, migration, and invasion. Dual-luciferase reporter gene assay was employed for detecting the targeting relationships of circ-CCND1 and miR-497-5p, as well as miR-497-5p and HMGA2, respectively. Western blot was used to detect the regulatory functions of circ-CCND1 and miR-497-5p on HMGA1 expression at protein level. Circ-CCND1 and HMGA2 expressions in HCC were significantly up-regulated and miR-497-5p expression was markedly decreased. High circ-CCND1 expression was associated with relatively large tumor size and lymph node metastasis in HCC patients. In addition, circ-CCND1 was mainly distributed in the cytoplasm of HCC cells. Functionally, knockdown of circ-CCND1 remarkably suppressed HCC cell proliferation, migration, and invasion. Mechanistically, miR-497-5p was a direct target of circ-CCND1 and miR-497-5p specifically modulated HMGA2 expression. Furthermore, miR-497-5p inhibitors and or HMGA2 overexpression partially counteracted the suppressing effect induced by si-circ-CCND1 on the malignant phenotype of HCC cells. Circ-CCND1 plays a cancer-promoting role in HCC by modulating the miR-497-5p/HMGA2 axis. Therefore, targeting circ-CCND1 is likely to be a promising therapeutic strategy for HCC.

LncRNA XIST upregulates TRIM25 via negatively regulating miR-192 in hepatitis B virus-related hepatocellular carcinoma

BACKGROUND

Long non-coding RNA (lncRNA) XIST has been implicated in the progression of a variety of tumor diseases. The purpose of this study was to explore the molecular role of lncRNA XIST in human hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC).

METHODS

The expression levels of lncRNA XIST, miR-192 and TRIM25 in HBV-related HCC tissues and HepG2.2.15 cells were detected by qRT-PCR. Biological information and luciferin gene reporter assay were performed to detect the interaction among lncRNA XIST, miR-192 and TRIM25. CCk-8 assay, wound healing assay and colony formation assay were conducted to detect the proliferation and migration ability of HepG2.2.15 cells.

RESULTS

qRT-PCR results showed that the expression levels of lncRNA XIST were remarkably increased in HBV-related HCC tissues and HepG2.2.15 cells. In addition, miR-192 was a direct target gene of lncRNA XIST, and the expression of miR-192 and lncRNA XIST were negatively correlated. Moreover, overexpression of miR-192 observably inhibited the proliferation and migration of HCC cells, while overexpression of lncRNA XIST showed an opposite effect. Furthermore, TRIM25 was a direct target of miR-192, and lncRNA XIST could up-regulate the expression of TRIM25 by targeting miR-192.

CONCLUSION

LncRNA XIST could up-regulate the expression of TRIM25 by targeting and binding to miR-192, thus accelerating the occurrence and development of HCC.

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.

The Latest Overview of circRNA in the Progression, Diagnosis, Prognosis, Treatment, and Drug Resistance of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the main causes of tumor-related deaths worldwide. Due to the lack of obvious early symptoms and the lack of sensitive screening indicators in the early stage of HCC, the vast majority of patients are diagnosed with advanced or metastatic HCC, resulting in dissatisfactory treatment result. Therefore, it is urgent to determine effective and sensitive diagnostic and prognostic indicators and to determine new therapeutic targets. Circular RNA (circRNA) is a type of non-coding RNA that has been neglected for a long time. In recent years, it has been proved to play an important role in the development of many human diseases. Increasing evidence shows that change in circRNA expression has an extensive effect on the biological behavior of HCC. In this study, we comprehensively tracked the latest progress of circRNA in the pathogenesis of HCC, and reviewed its role as a biomarker for diagnosis and prognosis prediction in patients with HCC. In addition, we also summarized the potential of circRNA as therapeutic target in HCC and its relationship with HCC drug resistance, providing clues for the clinical development of circRNA-based therapeutic strategies.

Recent Update on the Role of Circular RNAs in Hepatocellular Carcinoma

After being overlooked for decades, circular RNAs (circRNAs) have recently generated considerable interest. circRNAs play a role in a variety of normal and pathological biological processes, including hepatocarcinogenesis. Many circRNAs contribute to hepatocarcinogenesis through sponging of microRNAs (miRs) and disruption of cellular signaling pathways that play a part in control of cell proliferation, metastasis and apoptosis. In most cases, overexpressed circRNAs sequester miRs to cause de-repressed translation of mRNAs that encode oncogenic proteins. Conversely, low expression of circRNAs has also been described in hepatocellular carcinoma (HCC) and is associated with inhibited production of tumor suppressor proteins. Other functions of circRNAs that contribute to hepatocarcinogenesis include translation of truncated proteins and acting as adapters to regulate influence of transcription factors on target gene expression. circRNAs also affect hepatocyte transformation indirectly. For example, the molecules regulate immune surveillance of cancerous cells and influence the liver fibrosis that commonly precedes HCC. Marked over- or under-expression of circRNA expression in HCC, with correlating plasma concentrations, has diagnostic utility and assays of these RNAs are being developed as biomarkers of HCC. Although knowledge in the field has recently surged, the myriad of described effects suggests that not all may be vital to hepatocarcinogenesis. Nevertheless, investigation of the role of circRNAs is providing valuable insights that are likely to contribute to improved management of a serious and highly aggressive cancer.

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.

Circular RNAs in gastrointestinal cancer: Current knowledge, biomarkers and targeted therapy (Review)

Circular RNAs (circRNAs) are a type of endogenous non‑coding RNAs that are connected at the 3' and 5' ends by exon or intron cyclization, which forms a covalently closed loop. They are stable, well conserved, exhibit specific expression in mammalian cells and can function as microRNA (miRNA or miR) sponges to regulate the target genes of miRNAs, which influences biological processes. Such as tumor proliferation, invasion, metastasis, apoptosis and tumor stage. circRNAs represent promising candidates for clinical diagnosis and treatment. In the present review, the biogenesis, classification and functions of circRNAs in tumors are briefly summarized and discussed. In addition, the participation of circRNAs in signal transduction pathways regulating gastrointestinal cancer cellular functions is highlighted.