The RNA-binding protein SORBS2 suppresses hepatocellular carcinoma tumourigenesis and metastasis by stabilizing RORA mRNA

The RNA-binding protein sorbin and SH3 domain-containing 2 are transcriptionally regulated by specificity protein 1 and function as tumor suppressors in bladder cancer by stabilizing tissue factor pathway inhibitor

Sorbin and SH3 domain-containing 2 (SORBS2) is an RNA-binding protein and has been implicated in the development of some cancers. However, its role in bladder cancer (BC) is yet to be established. The expression of SORBS2 in BC tissues was determined from the Gene Expression Omnibus and Gene Expression Profiling Interactive Analysis databases and collected paired tumor/normal samples. The effects of SORBS2 on BC cells were detected by CCK-8, colony formation, Transwell, dual-luciferase, RNA immunoprecipitation, chromatin immunoprecipitation, and DNA pull-down assays. In vivo, BC cell growth and metastasis were studied by a xenograft subcutaneous model and a tail-vein metastasis model. The results showed that SORBS2 expression was significantly decreased in BC tissues and cells. SORBS2 overexpression inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition in vitro and tumor growth and metastasis in vivo, while silencing SORBS2 produced the opposite effect. Mechanistically, we found that SORBS2 enhanced the stability of tissue factor pathway inhibitor (TFPI) mRNA via direct binding to its 3' UTR. Restoration of TFPI expression reversed SORBS2 knockdown-induced malignant phenotypes of BC cells. In addition, SORBS2 expression was negatively regulated by the transcription factor specificity protein 1 (SP1). Conversely, SORBS2 can be transcriptionally regulated by SP1 and inhibit BC cell growth and metastasis via stabilization of TFPI mRNA, indicating SORBS2 may be a promising therapeutic target for BC.

Bivalent activity of super-enhancer RNA LINC02454 controls 3D chromatin structure and regulates glioma sensitivity to temozolomide

Glioma cell sensitivity to temozolomide (TMZ) is critical for effective treatment and correlates with patient survival, although mechanisms underlying this activity are unclear. Here, we reveal a new mechanism used by glioma cells to modulate TMZ sensitivity via regulation of SORBS2 and DDR1 genes by super-enhancer RNA LINC02454. We report that LINC02454 activity increases glioma cell TMZ sensitivity by maintaining long-range chromatin interactions between SORBS2 and the LINC02454 enhancer. By contrast, LINC02454 activity also decreased glioma cell TMZ sensitivity by promoting DDR1 expression. Our study suggests a bivalent function for super-enhancer RNA LINC02454 in regulating glioma cell sensitivity to TMZ.

MiR-484 promotes nonalcoholic fatty liver disease progression in mice via downregulation of Sorbs2

OBJECTIVE

MicroRNA 484 (miR-484) plays a pivotal role in the development and progression of different diseases and is typically described as a mitochondrial regulator. Whether miR-484 is involved in lipid metabolism or exerts a role in nonalcoholic fatty liver disease remains unclear.

METHODS

miR-484 levels were examined in the livers of male mice fed a high-fat diet and in hepatocytes treated with free fatty acids. Sorbin and SH3 structural domain-containing protein 2 (Sorbs2) were identified as a novel target of miR-484 by sequencing mRNA in the livers of miR-484 knockout mice. Sorbs2 liver-specific knockdown mice were constructed by tail vein injection of adeno-associated virus vector to miR-484 knockout mice. In addition, genetic manipulation of SORBS2 was performed in human hepatocyte lines, mouse primary hepatocytes, and the liver.

RESULTS

Serum and hepatic miR-484 levels are upregulated in nonalcoholic fatty liver disease mice. miR-484 knockdown ameliorated hepatocyte steatosis, whereas miR-484 overexpression increased hepatocyte lipid load. miR-484 knockdown-mediated alleviation of hepatic steatosis, liver injury, inflammation, and apoptosis was compromised after high-fat diet-induced knockdown of Sorbs2 in mouse liver and free fatty acid-induced primary mouse hepatocytes.

CONCLUSIONS

These results identify Sorbs2-mediated mitochondrial β-oxidation and apoptosis that promote miR-484 knockdown-mediated remission of hepatic steatosis.

ARID5B promoted the histone demethylation of SORBS2 and hampered the metastasis of ovarian cancer

Ovarian cancer (OVCA) is the 4th most common female tumor after breast cancer, cervical cancer, and endometrial cancer, and now is mainly treated with debulking surgery and postoperative cisplatin and paclitaxel-based combination chemotherapy regimens. However, OVCA is insidious in its development and recurrence occurred in some patients after treatment. It is of great significance to study the pathogenesis of ovarian cancer and identify more biomarkers. Recently, the role of histone methyltransferase (HMT) and histone demethylase (HDM) in oncogenesis and development of malignant tumors has raised attention. Unlike other JMJC demethylases that have both JMJC and ARID domains in a single molecule, PHF2 requires assembly into a complex with a DNA-binding subunit (ARID5B) and exerts its enzymatic activity. Therefore, the aim of this manuscript is to investigate the role of histone demethylases ARID5B-PHF2 complex in the metastasis of OVCA. As result, we found ARID5B and PHF2 are both low expressed in OVCA tumor tissues and cell lines and associated with diagnosis and prognosis. Also, ARID5B suppressed rearrangement of the cytoskeleton in the process of EMT in OVCA cell lines. The role of PHF2 as a tumor suppressor was also confirmed both in vivo and in vitro. SORBS2 is low expressed in OVCA tumor tissues and cell lines and associated with diagnosis and prognosis. The expression of SORBS2 is positively corelated with the expression of ARID5B and PHF2. The promoter of SORBS2 is proved combined with ARID5B. The expression of SORBS2 was increased due to ARID5B-PHF2 complex promoted the histone demethylation by mainly binding in site H3K36me2 and therefore promoting the transcription of SORBS2. In conclusion, ARID5B-PHF2 complex promoted the histone demethylation of SORBS2 by mainly bind in site H3K36me2 and therefore promote the transcription of SORBS2 then hampered the process of EMT and tumor generation of OVCA. These results provided a new perspective on the molecular mechanisms of OVCA development and offered a new target of clinical diagnose and treatment of OVCA.

MiR-21-3p in extracellular vesicles from vascular fibroblasts of spontaneously hypertensive rat promotes proliferation and migration of vascular smooth muscle cells

Enhanced proliferation and migration of vascular smooth muscle cells (VSMCs) contributes to vascular remodeling in hypertension. Adventitial fibroblasts (AFs)-derived extracellular vesicles (EVs) modulate vascular remodeling in spontaneously hypertensive rat (SHR). This study shows the important roles of EVs-mediated miR-21-3p transfer in VSMC proliferation and migration and underlying mechanisms in SHR. AFs and VSMCs were obtained from aorta of Wistar-Kyoto rat (WKY) and SHR. EVs were separated from AFs culture with ultracentrifugation method. MiR-21-3p content in the EVs of SHR was increased compared with those of WKY. MiR-21-3p mimic promoted VSMC proliferation and migration of WKY and SHR, while miR-21-3p inhibitor attenuated proliferation and migration only in the VSMCs of SHR. EVs of SHR stimulated VSMC proliferation and migration, which were attenuated by miR-21-3p inhibitor. Sorbin and SH3 domain containing 2 (SORBS2) mRNA and protein levels were reduced in the VSMCs of SHR. MiR-21-3p mimic inhibited, while miR-21-3p inhibitor promoted SORBS2 expressions in the VSMCs of both WKY and SHR. EVs of SHR reduced SORBS2 expression, which was prevented by miR-21-3p inhibitor. EVs of WKY had no significant effect on SORBS2 expressions. SORBS2 overexpression attenuated the roles of miR-21-3p mimic and EVs of SHR in promoting VSMC proliferation and migration of SHR. Overexpression of miR-21-3p in vivo promotes vascular remodeling and hypertension. These results indicate that miR-21-3p in the EVs of SHR promotes VSMC proliferation and migration via negatively regulating SORBS2 expression.

RNA-binding protein CPSF6 regulates IBSP to affect pyroptosis in gastric cancer

BACKGROUND

Extensive evidence has illustrated the promotive role of integrin binding sialoprotein (IBSP) in the progression of multiple cancers. However, little is known about the functions of IBSP in gastric cancer (GC) progression.

AIM

To investigate the mechanism underlying the regulatory effects of IBSP in GC progression, and the relationship between IBSP and cleavage and polyadenylation factor 6 (CPSF6) in this process.

METHODS

The mRNA and protein expression of relevant genes were assessed through real-time quantitative polymerase chain reaction and Western blot, respectively. Cell viability was evaluated by Cell Counting Kit-8 assay. Cell invasion and migration were evaluated by Transwell assay. Pyroptosis was measured by flow cytometry. The binding between CPSF6 and IBSP was confirmed by luciferase reporter and RNA immunoprecipitation (RIP) assays.

RESULTS

IBSP exhibited higher expression in GC tissues and cell lines than in normal tissues and cell lines. IBSP knockdown suppressed cell proliferation, migration, and invasion but facilitated pyroptosis. In the exploration of the regulatory mechanism of IBSP, potential RNA binding proteins for IBSP were screened with catRAPID omics v2.0. The RNA-binding protein CPSF6 was selected due to its higher expression in stomach adenocarcinoma. Luciferase reporter and RIP assays revealed that CPSF6 binds to the 3'-untranslated region of IBSP and regulates its expression. Knockdown of CPSF6 inhibited cell proliferation, migration, and invasion but boosted pyroptosis. Through rescue assays, it was uncovered that the retarded GC progression mediated by CPSF6 knockdown was reversed by IBSP overexpression.

CONCLUSION

Our study highlighted the vital role of the CPSF6/IBSP axis in GC, suggesting that IBSP might be an effective bio-target for GC treatment.

Comprehensive Characterization of RNA-Binding Proteins in Colon Adenocarcinoma Identifies a Novel Prognostic Signature for Predicting Clinical Outcomes and Immunotherapy Responses Based on Machine Learning

BACKGROUND

RNA-binding proteins (RBPs) are crucial factors that function in the posttranscriptional modification process and are significant in cancer.

OBJECTIVE

This research aimed for a multigene signature to predict the prognosis and immunotherapy response of patients with colon adenocarcinoma (COAD) based on the expression profile of RNA-binding proteins (RBPs).

METHODS

COAD samples retrieved from the TCGA and GEO datasets were utilized for a training dataset and a validation dataset. Totally, 14 shared RBP genes with prognostic significance were identified. Non-negative matrix factorization clusters defined by these RBPs could stratify COAD patients into two molecular subtypes. Cox regression analysis and identification of 8-gene signature categorized COAD patients into high- and low-risk populations with significantly different prognosis and immunotherapy responses.

RESULTS

Our prediction signature was superior to another five well-established prediction models. A nomogram was generated to quantificationally predict the overall survival (OS) rate, validated by calibration curves. Our findings also indicated that high-risk populations possessed an enhanced immune evasion capacity and low-risk populations might benefit immunotherapy, especially for the joint combination of PD-1 and CTLA4 immunosuppressants. DHX15 and LARS2 were detected with significantly different expressions in both datasets, which were further confirmed by qRTPCR and immunohistochemical staining.

CONCLUSION

Our observations supported an eight-RBP-related signature that could be applied for survival prediction and immunotherapy response of patients with COAD.

The mechanism of BUD13 m6A methylation mediated MBNL1-phosphorylation by CDK12 regulating the vasculogenic mimicry in glioblastoma cells

Vasculogenic mimicry (VM) is an endothelium-independent tumor microcirculation that provides adequate blood supply for tumor growth. The presence of VM greatly hinders the treatment of glioblastoma (GBM) with anti-angiogenic drugs. Therefore, targeting VM formation may be a feasible therapeutic strategy for GBM. The research aimed to evaluate the roles of BUD13, CDK12, MBNL1 in regulating VM formation of GBM. BUD13 and CDK12 were upregulated and MBNL1 was downregulated in GBM tissues and cells. Knockdown of BUD13, CDK12, or overexpression of MBNL1 inhibited GBM VM formation. METTL3 enhanced the stability of BUD13 mRNA and upregulated its expression through m6A methylation. BUD13 enhanced the stability of CDK12 mRNA and upregulated its expression. CDK12 phosphorylated MBNL1, thereby regulating VM formation of GBM. The simultaneous knockdown of BUD13, CDK12, and overexpression of MBNL1 reduced the volume of subcutaneously transplanted tumors in nude mice and prolonged the survival period. Thus, the BUD13/CDK12/MBNL1 axis plays a crucial role in regulating VM formation of GBM and provides a potential target for GBM therapy.

Plateau Adaptation Gene Analyses Reveal Transcriptomic, Proteomic, and Dual Omics Expression in the Lung Tissues of Tibetan and Yorkshire Pigs

Elevated environments such as plateaus are often classified as low oxygen environments. The hypoxic adaptation mechanisms utilized by organisms in these conditions are not well understood. To address this, the differentially expressed genes (DEGs) involved in hypoxia adaptation were assessed using two pig breeds (Tibetan pig [TP] and Yorkshire sow [YY]). Genes related to lung tissue responses to hypoxia were assessed using transcriptomic (using RNA-seq) and proteomic (using iTRAQ) analysis. A total of 1021 DEGs were screened out. In the iTRAQ omics data, a total of 22,100 peptides were obtained and 4518 proteins were found after filtering. A total of 271 differentially expressed proteins [DEPs] were screened using the conditions of p < 0.05; FC ≤ 0.833; and FC ≥ 1.2. A total of 14 DEGs at the mRNA and protein levels were identified and found to be associated with regulation of the inflammatory response; blood particles; and MAPK cascade response regulation. Among the DEGs, six were associated with hypoxia adaptation function (mitochondria and glycolysis) in pigs. The results of this study identify novel candidate genes involved in porcine hypoxia adaptation mechanisms.

Heparan sulfate proteoglycans-mediated targeted delivery of TGF-β1-binding peptide to liver for improved anti-liver fibrotic activity in vitro and in vivo

Elevated expressions of transforming growth factor β1 (TGF-β1) have been implicated in the pathogenesis of liver fibrosis, thus attenuating the excessive TGF-β1's activity by TGF-β1-binding peptide is an ideal strategy for the treatment of liver fibrosis. However, the application of small peptide as a pharmaceutical agent is obstacle due to difficult preparation and non-selective delivery. The I-plus sequences of circumsporozoite protein (CSP-I) possesses high affinity for heparan sulfate proteoglycans, which are primarily located on liver tissues. TGF-β1-binding peptide P15 holds specific ability of binding to TGF-β1. In this study, we describe an approach to efficiently preparing liver-targeting peptide P15-CSP-I, which is conjugation of the sequences of P15 to the N-terminus of CSP-I, from the cleavage of biological macromolecule SUMO-tagged P15-CSP-I. In vitro and ex vivo binding assay showed that P15-CSP-I specifically targeted to the hepatocytes and liver tissues. Moreover, P15-CSP-I inhibited cell proliferation, migration and invasion, and decreased fibrosis-related proteins expression in TGF-β1-activated HSCs in vitro. Furthermore, P15-CSP-I ameliorated liver morphology and decreased the fibrosis responses in vivo. Taken together, P15-CSP-I may be a potential candidate for targeting therapy on liver fibrosis due to its high efficient preparation, specific liver-targeting potential and improved anti-liver fibrotic activity.

SORBS2 as a molecular target for atherosclerosis in patients with familial hypercholesterolemia

Background

Familial hypercholesterolemia (FH) is a metabolic disease in which patients are prone to develop premature atherosclerosis (AS). Sorbin and SH3 Domain Containing 2 (SORBS2) is known to play a role in coronary heart disease (CHD). However, the mechanism underlying SORBS2 involvement in the development of hypercholesterolemia remains unknown. Here, we investigated the effects of SORBS2 on inflammation and foam cell formation and its underlying mechanisms.

Methods

Using Bioinformatics analysis, we established that SORBS2 is upregulated in patients with FH. Circulating concentrations of SORBS2 were measured using ELISA kit (n = 30). The association between circulating SORBS2 levels and inflammatory factors or lipid indexes were conducted using Spearman correlation analysis. We further conducted in vitro experiments that the expression of SORBS2 were analyzed, and SORBS2 siRNA were transfected into oxidized LDL (OxLDL)-induced macrophages, followed by western blot and immunofluorescence.

Results

Circulating SORBS2 levels were positively associated with inflammatory factors and lipid indexes. We also observed that high in vitro expression of SORBS2 in OxLDL-induced macrophages. After SORBS2 silencing, Nod like receptor family pyrin domain-containing 3 protein(NLRP3)-Caspase1 activation and NF-κB activation were attenuated, and secretion of pro-inflammatory cytokines (IL-1β and IL-18) was decreased. Moreover, SORBS2 silencing blocked reactive oxygen species (ROS) production and lipid accumulation, and promoted cholesterol efflux through ABCG1-PPARγ pathway.

Conclusions

SORBS2 regulates lipid-induced inflammation and foam cell formation, and is a potential therapeutic target for hypercholesterolemia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03381-z.

E2F1‐mediated AUF1 upregulation promotes HCC development and enhances drug resistance via stabilization of AKR1B10

The AU‐rich binding factor 1 (AUF1) is one of the well known adenylate‐uridylate‐rich element (ARE)‐specific RNA‐binding proteins (ARE‐BPs) for which dysregulation has been reported in various human cancers. However, the involvement of AUF1 in the initiation and progression of hepatocellular carcinoma (HCC) is still elusive. In this study, we aimed at exploring the clinical significance, function, and mechanism of the abnormal expression of AUF1 in HCC. Using a bioinformatics analysis of The Cancer Genome Atlas (TCGA) and Liver Cancer Institute (LCI) database, we identified that AUF1 was abnormally highly expressed in HCC tissues and that the high expression of AUF1 was correlated with poor prognosis in patients with HCC. We also confirmed the increased AUF1 expression and its prognostic value in our HBV‐related HCC cohorts. AUF1 overexpression in hepatoma cells promoted cell proliferation and increased the resistance of hepatoma cells toward doxorubicin, whereas knockdown of AUF1 exerted the opposite effects. Mechanistically, we demonstrated that AKR1B10 was a critical target of AUF1 and was essential for sustaining the AUF1‐induced proliferation and drug resistance of hepatoma cells. AUF1 increased AKR1B10 expression by binding to the 3′UTR region of AKR1B10 mRNA and stabilizing AKR1B10 mRNA. Additionally, we demonstrated that E2F1 enhanced AUF1 expression in HCC at the transcription level. Our study revealed a novel role of AUF1 in promoting the development and drug resistance of HCC via the post‐transcriptional regulation of AKR1B10 expression. The E2F1/AUF1/AKR1B10 axis can serve as a potential therapeutic target in HCC.

The RNA-binding protein GRSF1 promotes hepatocarcinogenesis via competitively binding to YY1 mRNA with miR-30e-5p

Background

Dysregulation of RNA binding protein (RBP) expression has been confirmed to be causally linked with tumorigenesis. The detailed biological effect and underlying mechanisms of the RBP GRSF1 in hepatocellular carcinoma (HCC) remain unclear.

Methods

HCC cells with stable knockdown of GRSF1 were established using two sh-RNA-encoding lentiviruses. The functions of GRSF1 in HCC were explored using MTT, colony formation, flow cytometry, and Transwell assays and a xenograft model. Transcriptomic sequencing in GRSF1-deficient MHCC-97H cells was carried out to identify the downstream effector of GRSF1. The regulatory mechanisms among GRSF1, YY1 and miR-30e-5p were investigated via RNA immunoprecipitation, luciferase, RNA pull-down and ChIP assays. Several in vivo assays were used to assess the selectivity of the small-molecule compound VE-821 in HCC and to confirm the absence of general toxicity in animal models.

Results

GRSF1 was frequently increased in HCC tissue and cells and was associated with worse clinical outcomes. GRSF1 functions as a novel oncogenic RBP by enhancing YY1 mRNA stability, and the GUUU motifs within the YY1 3`UTR 2663-2847 were the specific binding motifs for GRSF1. YY1 feedback promoted GRSF1 expression by binding to the GRSF1 promoter. In addition, YY1 was a critical target of miR-30e-5p, which was confirmed in this study to inhibit HCC hepatocarcinogenesis. GRSF1 and miR-30e-5p competitively regulated YY1 by binding to its 3`UTR 2663-2847 region. Finally, we identified that VE-821 blocked HCC progression by inhibiting the GRSF1/YY1 pathway.

Conclusion

This study revealed the interaction network among GRSF1, YY1 and miR-30e-5p, providing new insight into HCC pathogenesis, and indicated that VE821 may serve as a novel agent with potential for HCC treatment through inhibition of the GRSF1/YY1 axis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02217-w.

Development of an Eight-gene Prognostic Model for Overall Survival Prediction in Patients with Hepatocellular Carcinoma

BACKGROUND AND AIMS

The overall survival (OS) of hepatocellular carcinoma (HCC) remains dismal. Bioinformatic analysis of transcriptome data could identify patients with poor OS and may facilitate clinical decision. This study aimed to develop a prognostic gene model for HCC.

METHODS

GSE14520 was retrieved as a training set to identify differential expressed genes (DEGs) between tumor and adjacent liver tissues in HCC patients with different OS. A DEG-based prognostic model was then constructed and the TCGA-LIHC and ICGC-LIRI datasets were used to validate the model. The area under the receiver operating characteristic curve (AUC) and hazard ratio (HR) of the model for OS were calculated. A model-based nomogram was established and verified.

RESULTS

In the training set, differential expression analysis identified 80 genes dysregulated in oxidation-reduction and metabolism regulation. After univariate Cox and LASSO regression, eight genes (LPCAT1, DHRS1, SORBS2, ALDH5A1, SULT1C2, SPP1, HEY1 and GOLM1) were selected to build the prognostic model. The AUC for 1-, 3- and 5-year OS were 0.779, 0.736, 0.754 in training set and 0.693, 0.689, 0.693 in the TCGA-LIHC validation set, respectively. The AUC for 1- and 3-year OS were 0.767 and 0.705 in the ICGC-LIRI validation set. Multivariate analysis confirmed the model was an independent prognostic factor (training set: HR=4.422, p<0.001; TCGA-LIHC validation set: HR=2.561, p<0.001; ICGC-LIRI validation set: HR=3.931, p<0.001). Furthermore, a nomogram combining the model and AJCC stage was established and validated, showing increased OS predictive efficacy compared with the prognostic model (p=0.035) or AJCC stage (p<0.001).

CONCLUSIONS

Our eight-gene prognostic model and the related nomogram represent as reliable prognostic tools for OS prediction in HCC patients.

CircSERPINA3 regulates SERPINA3-mediated apoptosis, autophagy and aerobic glycolysis of prostate cancer cells by competitively binding to MiR-653-5p and recruiting BUD13

BACKGROUND

Prostate cancer (PCa) belongs to an epithelial malignancy that occurs in the prostate gland and is the most common malignancy of the male genitourinary system. Referring to related literature, circSERPINA3 has been reported to be up-regulated in PCa. However, its biological function remains unclear.

PURPOSE

This study aimed to reveal the specific role and relevant molecular mechanism of circSERPINA3 in PCa.

METHODS

RT-qPCR was used to examine gene expression and functional analyses were conducted to verify the effect of circSERPINA3 on cell apoptosis, autophagy and aerobic glycolysis in PCa cells. Mechanism assays were applied to evaluate the relationship among circSERPINA3/miR-653-5p/SERPINA3/BUD13.

RESULTS

CircSERPINA3 was verified to be up-regulated in PCa cells and to inhibit cell apoptosis while promoting aerobic glycolysis and autophagy in PCa cells. CircSERPINA3 and SERPINA3 were also testified to bind to miR-653-5p through a line of mechanism experiments. Moreover, it was discovered that circSERPINA3 could stabilize SERPINA3 mRNA via recruiting BUD13. Additionally, SERPINA3 was verified to inhibit cell apoptosis, while promoting aerobic glycolysis and autophagy in PCa cells.

CONCLUSIONS

Our study suggested that circSERPINA3 regulated apoptosis, autophagy and aerobic glycolysis of PCa cells by competitively binding to miR-653-5p and recruiting BUD13.

Novel oncogenes and tumor suppressor genes in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a very deadly disease. HCC initiation and progression involve multiple genetic events, including the activation of proto-oncogenes and disruption of the function of specific tumor suppressor genes. Activation of oncogenes stimulates cell growth and survival, while loss-of-function mutations of tumor suppressor genes result in unrestrained cell growth. In this review, we summarize the new findings that identified novel proto-oncogenes and tumor suppressors in HCC over the past five years. These findings may inspire the development of novel therapeutic strategies to improve the outcome of HCC patients.

miR-18a-5p Facilitates Malignant Progression of Head and Neck Squamous Cell Carcinoma Cells via Modulating SORBS2

This study attempted to investigate possible molecular mechanism and role of miR-18a-5p in head and neck squamous cell carcinoma (HNSCC). Differential miRNAs and their possible targets were analyzed through TCGA database. By conducting qRT-PCR, miR-18a-5p was tested to be increased and SORBS2 was assessed to be downregulated in HNSCC cells. CCK-8, Transwell, and flow cytometry assays disclosed that miR-18a-5p facilitated HNSCC cell proliferation, migration, and invasion and repressed cell apoptosis. By dual-luciferase reporter gene assay, it was verified that miR-18a-5p had binding sites into SORBS2. Rescue experiments displayed that forced expression of SORBS2 restored the impact of miR-18a-5p overexpression on HNSCC cells. Collectively, our research preliminarily identified the promotion effect of miR-18a-5p/SORBS2 axis on malignant phenotypes of HNSCC cells. Our findings may provide a preclinical reference for HNSCC treatment.

Identification and validation of RNA-binding protein-related gene signature revealed potential associations with immunosuppression and drug sensitivity in glioma

Background

Glioma is the most common central nervous system tumor in adults, and a considerable part of them are high‐degree ones with high malignancy and poor prognosis. At present, the classification and treatment of glioma are mainly based on its histological characteristics, so studies at the molecular level are needed.

Methods

RNA‐seq data from The Cancer Genome Atlas (TCGA) datasets (n = 703) and Chinese Glioma Genome Atlas (CGGA) were utilized to find out the differentially expressed RNA‐binding proteins (RBPs) between normal cerebral tissue and glioma. A prediction system for the prognosis of glioma patients based on 11 RBPs was established and validated using uni‐ and multi‐variate Cox regression analyses. STITCH and CMap databases were exploited to identify putative drugs and their targets. Single sample gene set enrichment analysis (ssGSEA) was used to calculate scores of specific immune‐related gene sets. IC50 of over 20,000 compounds in 60 cancer cell lines was collected from the CellMiner database to test the drug sensitivity prediction value of the RBP‐based signature.

Results

We established a reliable prediction system for the prognosis of glioma patients based on 11 RBPs including THOC3, LSM11, SARNP, PABPC1L2B, SMN1, BRCA1, ZC3H8, DZIP1L, HEXIM2, LARP4B, and ZC3H12B. These RBPs were primarily associated with ribosome and post‐transcriptional regulation. RBP‐based risk scores were closely related to immune cells and immune function. We also confirmed the potential of the signature to predict the drug sensitivity of currently approved or evaluated drugs.

Conclusions

Differentially expressed RBPs in glioma can be used as a basis for prognosis prediction, new drugs screening and drug sensitivity prediction. As RBP‐based glioma risk scores were associated with immunity, immunotherapy may become an important treatment for glioma in the future.

Comprehensive characterization of pathological stage-related genes of papillary thyroid cancer along with survival prediction

It is crucial to understand the differences across papillary thyroid cancer (PTC) stages, so as to provide a basis for individualized treatments. Here, comprehensive function characterization of PTC stage‐related genes was performed and a new prognostic signature was developed for advanced patients. Two gene modules were confirmed to be closely associated with PTC stages and further six hub genes were identified that yield excellent diagnostic efficiency between tumour and normal tissues. Genetic alteration analysis indicates that they are much conservative since mutations in the DNA of them rarely occur, but changes of DNA methylation on these six genes show that 12 DNA methylation sites are significantly associated with their corresponding genes' expression. Validation data set testing also suggests that these six stage‐related hub genes would be probably potential biomarkers for marking four stages. Subsequently, a 21‐mRNA‐based prognostic risk model was constructed for PTC stage III/IV patients and it could effectively predict the survival of patients with strong prognostic ability. Functional analysis shows that differential expression genes between high‐ and low‐risk patients would promote the progress of PTC to some extent. Moreover, tumour microenvironment (TME) of high‐risk patients may be more conducive to tumour growth by ESTIMATE analysis.

A novel five-gene signature predicts overall survival of patients with hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common public health challenges, worldwide. Because of molecular complexity and tumor heterogeneity, there are no effective predictive models for prognosis of HCC. This underlines the unmet need for accurate prognostic models for HCC. Analysis of GSE14520 data from gene omnibus (GEO) database identified multiple differentially expressed mRNAs (DEMs) between HCC and normal tissues. After randomly stratifying the patients into the training and testing groups, we performed univariate, lasso, and multivariable Cox regression analyses to delineate the prognostic gene signature in training set. We then used Kaplan-Meier plot, time-dependent receiver operating characteristic (ROC), multivariable Cox regression analysis of clinical information, nomogram, and decision curve analysis (DCA) to evaluate the predictive and overall survival value of a novel five-gene signature (CNIH4, SOX4, SPP1, SORBS2, and CCL19) within and across sets, separately and combined. We also validated the prognostic value of the five-gene signature using The Cancer Genome Atlas-Liver Hepatocellular Carcinoma (TCGA-LIHC), GSE54236 and International Cancer Genome Consortium (ICGC) sets. Multivariable Cox regression analysis revealed that the five-gene signature and tumor node metastasis (TNM) stage were independent prognostic factors for overall survival of HCC patients in GSE14520 and TCGA-LIHC. Combining TNM stage clinical pathological parameters and nomogram greatly improved the prognosis prediction of HCC. Further gene set enrichment analysis (GSEA) revealed enrichment of KEGG pathways related to cell cycle in the high-risk group and histidine metabolism in the low-risk group. Finally, all these five mRNAs are overexpressed between 12 pairs of HCC and adjacent normal tissues by quantitative real-time PCR validation. In brief, a five-gene prognostic signature and a nomogram were identified and constructed, respectively, and further validated for their HCC prognostic value. The five-gene risk score together with TNM stage models could aid in rationalizing customized therapies in HCC patients.

Musk ketone induces apoptosis of gastric cancer cells via downregulation of sorbin and SH3 domain containing 2

Musk ketone exerts antiproliferative effects on several types of cancer, such as lung and breast cancer. However, the effects and underlying mechanisms of action of musk ketone in gastric cancer (GC) are poorly understood. The present study aimed to investigate the effects of musk ketone in GC cells. The present study indicated that musk ketone exerted significant anticancer effects on GC cells. The IC₅₀ values of musk ketone were 4.2 and 10.06 µM in AGS and HGC-27 cells, respectively. Low dosage of musk ketone significantly suppressed the proliferation and colony formation of AGS and HGC-27 cells. Cell cycle arrest and apoptosis were induced by musk ketone. Furthermore, microarray data indicated that musk ketone treatment led to downregulation of various genes, including sorbin and SH3 domain containing 2 (SORBS2). Reverse transcription-quantitative PCR and immunoblotting results indicated that musk ketone repressed mRNA and protein expression levels of SORBS2. It was also shown that knockdown of SORBS2 inhibited the proliferation and colony formation of HGC-27 cells. The antiproliferative effects of musk ketone were decreased in HGC-27 cells with SORBS2 silencing. In summary, the present study indicated that musk ketone suppressed the proliferation and growth of GC partly by downregulating SORBS2 expression.

Molecular structure, gene expression and functional role of WFDC1 in angiogenesis and cancer

Whey acidic proteins (WAP) perform a diverse range of important biological functions, including proteinase activity, calcium transport and bacterial growth. The WAP four-disulphide core domain protein 1 (WFDC1) gene (also called PS20), encodes the 20 kDa prostate stromal protein (ps20), which is a member of the WAP-type four-disulphide core domain family of proteins, and exhibits characteristics of serine protease inhibitors, such as elafin and secretory leukocyte protease inhibitor. Molecular structural analysis reveals that ps20 consists of four-disulphide bonds formed by eight cysteine residues located at the carboxyl terminus of the protein. Wfdc1-null mice were found to display no overt developmental phenotype, suggesting a dispensable role in organ growth and development. However, WFDC1 was able to mediate endothelial cell migration and pericyte stabilization, which are vital for the formation of functional vascular structures. WFDC1 was also found to be downregulated in cancers and exhibited a regulatory effect on cell proliferation. In addition, it was involved in the modulation of memory T cells during human immunodeficiency virus infection. Gaining a solid understanding of the mechanisms by which WFDC1 regulates tissue homeostasis and disease processes, in a tissue specific manner, will be an important move towards the development of WFDC1/ps20 as potential therapeutic targets.

Systematic Construction and Validation of an RNA-Binding Protein-Associated Model for Prognosis Prediction in Hepatocellular Carcinoma

BACKGROUND

Evidence from prevailing studies show that hepatocellular carcinoma (HCC) is among the top cancers with high mortality globally. Gene regulation at post-transcriptional level orchestrated by RNA-binding proteins (RBPs) is an important mechanism that modifies various biological behaviors of HCC. Currently, it is not fully understood how RBPs affects the prognosis of HCC. In this study, we aimed to construct and validate an RBP-related model to predict the prognosis of HCC patients.

METHODS

Differently expressed RBPs were identified in HCC patients based on the GSE54236 dataset from the Gene Expression Omnibus (GEO) database. Integrative bioinformatics analyses were performed to select hub genes. Gene expression patterns were validated in The Cancer Genome Atlas (TCGA) database, after which univariate and multivariate Cox regression analyses, as well as Kaplan-Meier analysis were performed to develop a prognostic model. Then, the performance of the prognostic model was assessed using receiver operating characteristic (ROC) curves and clinicopathological correlation analysis. Moreover, data from the International Cancer Genome Consortium (ICGC) database were used for external validation. Finally, a nomogram combining clinicopathological parameters and prognostic model was established for the individual prediction of survival probability.

RESULTS

The prognostic risk model was finally constructed based on two RBPs (BOP1 and EZH2), facilitating risk-stratification of HCC patients. Survival was markedly higher in the low-risk group relative to the high-risk group. Moreover, higher risk score was associated with advanced pathological grade and late clinical stage. Besides, the risk score was found to be an independent prognosis factor based on multivariate analysis. Nomogram including the risk score and clinical stage proved to perform better in predicting patient prognosis.

CONCLUSIONS

The RBP-related prognostic model established in this study may function as a prognostic indicator for HCC, which could provide evidence for clinical decision making.

RNA-binding protein SORBS2 suppresses clear cell renal cell carcinoma metastasis by enhancing MTUS1 mRNA stability

RNA-binding proteins (RBPs) predominantly contribute to abnormal posttranscriptional gene modulation and disease progression in cancer. Sorbin and SH3 domain-containing 2 (SORBS2), an RBP, has been reported to be a potent tumor suppressor in several cancer types. Through integrative analysis of clinical specimens, we disclosed that the expression level of SORBS2 was saliently decreased in metastatic tissues and positively correlated with overall survival. We observed that overexpression of SORBS2 brought about decreased metastatic capacity in ccRCC cell lines. Transcriptome-wide analysis revealed that SORBS2 notably increased microtubule-associated tumor-suppressor 1 gene (MTUS1) expression. In-depth mechanistic exploring discovered that the Cys2-His2 zinc finger (C2H2-ZnF) domain of SORBS2 directly bound to the 3′ untranslated region (3′UTR) of MTUS1 mRNA, which increased MTUS1 mRNA stability. In addition, we identified that MTUS1 regulated microtubule dynamics via promoting KIF2C^S192 phosphorylation by Aurora B. Together, our research identified SORBS2 as a suppressor of ccRCC metastasis by enhancing MTUS1 mRNA stability, providing a novel understanding of RBPs during ccRCC progression.

Development and validation of an RNA binding protein-associated prognostic model for hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is among the deadliest forms of cancer. While RNA-binding proteins (RBPs) have been shown to be key regulators of oncogenesis and tumor progression, their dysregulation in the context of HCC remains to be fully characterized.

METHODS

Data from the Cancer Genome Atlas - liver HCC (TCGA-LIHC) database were downloaded and analyzed in order to identify RBPs that were differentially expressed in HCC tumors relative to healthy normal tissues. Functional enrichment analyses of these RBPs were then conducted using the GO and KEGG databases to understand their mechanistic roles. Central hub RBPs associated with HCC patient prognosis were then detected through Cox regression analyses, and were incorporated into a prognostic model. The prognostic value of this model was then assessed through the use of Kaplan-Meier curves, time-related ROC analyses, univariate and multivariate Cox regression analyses, and nomograms. Lastly, the relationship between individual hub RBPs and HCC patient overall survival (OS) was evaluated using Kaplan-Meier curves. Finally, find protein-coding genes (PCGs) related to hub RBPs were used to construct a hub RBP-PCG co-expression network.

RESULTS

In total, we identified 81 RBPs that were differentially expressed in HCC tumors relative to healthy tissues (54 upregulated, 27 downregulated). Seven prognostically-relevant hub RBPs (SMG5, BOP1, LIN28B, RNF17, ANG, LARP1B, and NR0B1) were then used to generate a prognostic model, after which HCC patients were separated into high- and low-risk groups based upon resultant risk score values. In both the training and test datasets, we found that high-risk HCC patients exhibited decreased OS relative to low-risk patients, with time-dependent area under the ROC curve values of 0.801 and 0.676, respectively. This model thus exhibited good prognostic performance. We additionally generated a prognostic nomogram based upon these seven hub RBPs and found that four other genes were significantly correlated with OS.

CONCLUSION

We herein identified a seven RBP signature that can reliably be used to predict HCC patient OS, underscoring the prognostic relevance of these genes.

A Five-Gene Signature for Recurrence Prediction of Hepatocellular Carcinoma Patients

Background

Hepatocellular carcinoma (HCC) is one of the most aggressive malignancies with poor prognosis. There are many selectable treatments with good prognosis in Barcelona Clinic Liver Cancer- (BCLC-) 0, A, and B HCC patients, but the most crucial factor affecting survival is the high recurrence rate after treatments. Therefore, it is of great significance to predict the recurrence of BCLC-0, BCLC-A, and BCLC-B HCC patients.

Aim

To develop a gene signature to enhance the prediction of recurrence among HCC patients.

Materials and Methods

The RNA expression data and clinical data of HCC patients were obtained from the Gene Expression Omnibus (GEO) database. Univariate Cox regression analysis and least absolute shrinkage and selection operator (LASSO) regression analysis were conducted to screen primarily prognostic biomarkers in GSE14520. Multivariate Cox regression analysis was introduced to verify the prognostic role of these genes. Ultimately, 5 genes were demonstrated to be related with the recurrence of HCC patients and a gene signature was established. GSE76427 was adopted to further verify the accuracy of gene signature. Subsequently, a nomogram based on gene signature was performed to predict recurrence. Gene functional enrichment analysis was conducted to investigate the potential biological processes and pathways.

Results

We identified a five-gene signature which performs a powerful predictive ability in HCC patients. In the training set of GSE14520, area under the curve (AUC) for the five-gene predictive signature of 1, 2, and 3 years were 0.813, 0.786, and 0.766. Then, the relative operating characteristic (ROC) curves of five-gene predictive signature were verified in the GSE14520 validation set, the whole GSE14520, and GSE76427, showed good performance. A nomogram comprising the five-gene signature was built so as to show a good accuracy for predicting recurrence-free survival of HCC patients.

Conclusion

The novel five-gene signature showed potential feasibility of recurrence prediction for early-stage HCC.

Effects of RNA Binding Proteins on the Prognosis and Malignant Progression in Prostate Cancer

Prostate cancer (PCa) is a common lethal malignancy in men. RNA binding proteins (RBPs) have been proven to regulate the biological processes of various tumors, but their roles in PCa remain less defined. In the present study, we used bioinformatics analysis to identify RBP genes with prognostic and diagnostic values. A total of 59 differentially expressed RBPs in PCa were obtained, comprising 28 upregulated and 31 downregulated RBP genes, which may play important roles in PCa. Functional enrichment analyses showed that these RBPs were mainly involved in mRNA processing, RNA splicing, and regulation of RNA splicing. Additionally, we identified nine RBP genes (EXO1, PABPC1L, REXO2, MBNL2, MSI1, CTU1, MAEL, YBX2, and ESRP2) and their prognostic values by a protein-protein interaction network and Cox regression analyses. The expression of these nine RBPs was validated using immunohistochemical staining between the tumor and normal samples. Further, the associations between the expression of these nine RBPs and pathological T staging, Gleason score, and lymph node metastasis were evaluated. Moreover, these nine RBP genes showed good diagnostic values and could categorize the PCa patients into two clusters with different malignant phenotypes. Finally, we constructed a prognostic model based on these nine RBP genes and validated them using three external datasets. The model showed good efficiency in predicting patient survival and was independent of other clinical factors. Therefore, our model could be used as a supplement for clinical factors to predict patient prognosis and thereby improve patient survival.

Integrated analysis of transcriptomic and proteomic analyses reveals different metabolic patterns in the livers of Tibetan and Yorkshire pigs

Objective

Tibetan pigs, predominantly originating from the Tibetan Plateau, have been subjected to long-term natural selection in an extreme environment. To characterize the metabolic adaptations to hypoxic conditions, transcriptomic and proteomic expression patterns in the livers of Tibetan and Yorkshire pigs were compared.

Methods

RNA and protein were extracted from liver tissue of Tibetan and Yorkshire pigs (n = 3, each). Differentially expressed genes and proteins were subjected to gene ontology and Kyoto encyclopedia of genes and genomes functional enrichment analyses.

Results

In the RNA-Seq and isobaric tags for relative and absolute quantitation analyses, a total of 18,791 genes and 3,390 proteins were detected and compared. Of these, 273 and 257 differentially expressed genes and proteins were identified. Evidence from functional enrichment analysis showed that many genes were involved in metabolic processes. The combined transcriptomic and proteomic analyses revealed that small molecular biosynthesis, metabolic processes, and organic hydroxyl compound metabolic processes were the major processes operating differently in the two breeds. The important genes include retinol dehydrogenase 16, adenine phosphoribosyltransferase, prenylcysteine oxidase 1, sorbin and SH3 domain containing 2, ENSSSCG00000036224, perilipin 2, ladinin 1, kynurenine aminotransferase 1, and dimethylarginine dimethylaminohydrolase 1.

Conclusion

The findings of this study provide novel insight into the high-altitude metabolic adaptation of Tibetan pigs.

LncRNA H19 Inhibits the Progression of Sepsis-Induced Myocardial Injury via Regulation of the miR-93-5p/SORBS2 Axis

Sepsis is an infectious disease that seriously endangers human health. It usually leads to myocardial injury which seriously endangers to the health of human beings. H19 has been confirmed to play key roles in various diseases, including sepsis. However, its function in the progression of sepsis-induced myocardial injury remains largely unknown. H9C2 cells were treated with lipopolysaccharide (LPS) to mimic sepsis-induced myocardial injury in vitro. Cell proliferation and apoptosis were detected by MTT assay and flow cytometry, respectively. In addition, gene and protein expression levels in H9C2 cells were measured by quantitative real-time PCR (qRT-PCR) and Western blotting. The levels of inflammatory cytokines in H9C2 cell supernatants were tested by ELISA. JC-1 staining was performed to observe the mitochondrial membrane potential level in H9C2 cells. H19 and SORBS2 were downregulated in H9C2 cells following LPS treatment, while miR-93-5p was upregulated. Moreover, LPS-induced cell growth inhibition and mitochondrial damage were significantly reversed by overexpression of H19. In addition, H19 upregulation notably suppressed LPS-induced inflammatory responses in H9C2 cells. Moreover, H19 sponged miR-93-5p to promote SORBS2 expression. Overall, H19 suppressed sepsis-induced myocardial injury via regulation of the miR-93-5p/SORBS2 axis. H19 attenuated the development of sepsis-induced myocardial injury in vitro via modulation of the miR-93-5p/SORBS2 axis. Thus, H19 could serve as a potential target for the treatment of sepsis-induced myocardial injury.

Genetic Animal Models for Arrhythmogenic Cardiomyopathy

Arrhythmogenic cardiomyopathy has been clinically defined since the 1980s and causes right or biventricular cardiomyopathy associated with ventricular arrhythmia. Although it is a rare cardiac disease, it is responsible for a significant proportion of sudden cardiac deaths, especially in athletes. The majority of patients with arrhythmogenic cardiomyopathy carry one or more genetic variants in desmosomal genes. In the 1990s, several knockout mouse models of genes encoding for desmosomal proteins involved in cell-cell adhesion revealed for the first time embryonic lethality due to cardiac defects. Influenced by these initial discoveries in mice, arrhythmogenic cardiomyopathy received an increasing interest in human cardiovascular genetics, leading to the discovery of mutations initially in desmosomal genes and later on in more than 25 different genes. Of note, even in the clinic, routine genetic diagnostics are important for risk prediction of patients and their relatives with arrhythmogenic cardiomyopathy. Based on improvements in genetic animal engineering, different transgenic, knock-in, or cardiac-specific knockout animal models for desmosomal and nondesmosomal proteins have been generated, leading to important discoveries in this field. Here, we present an overview about the existing animal models of arrhythmogenic cardiomyopathy with a focus on the underlying pathomechanism and its importance for understanding of this disease. Prospectively, novel mechanistic insights gained from the whole animal, organ, tissue, cellular, and molecular levels will lead to the development of efficient personalized therapies for treatment of arrhythmogenic cardiomyopathy.

MiR-18a-downregulated RORA inhibits the proliferation and tumorigenesis of glioma using the TNF-α-mediated NF-κB signaling pathway

BACKGROUND

Glioma has a poor prognosis, and is the most common primary and lethal primary malignant tumor in the central nervous system. Retinoic acid receptor-related orphan receptor A (RORA) is a member of the ROR subfamily of orphan receptors and plays an anti-tumor role in several cancers.

METHODS

A cell viability assay, the Edu assay, neurosphere formation assay, and xenograft experiments were used to detect the proliferative abilities of glioma cell line, glioma stem cells (GSCs). Western blotting, ELISAs, and luciferase reporter assays were used to detect the presence of possible microRNAs.

FINDINGS

Our study found for the first time that RORA was expressed at low levels in gliomas, and was associated with a good prognosis. RORA overexpression inhibited the proliferation and tumorigenesis of glioma cell lines and GSCs via inhibiting the TNF-α mediated NF-κB signaling pathway. In addition, microRNA-18a had a promoting effect on gliomas, and was the possible reason for low RORA expression in gliomas.

INTERPRETATION

RORA may be a promising therapeutic target in the treatment of gliomas.

Integrated analysis of the roles and prognostic value of RNA binding proteins in lung adenocarcinoma

Lung cancer is the top cause of carcinoma-associated deaths worldwide. RNA binding proteins (RBPs) dysregulation has been reported in various malignant tumors, and that dysregulation is closely associated with tumorigenesis and tumor progression. However, little is known about the roles of RBPs in lung adenocarcinoma (LUAD). In this study, we downloaded the RNA sequencing data of LUAD from The Cancer Genome Atlas (TCGA) database and determined the differently expressed RBPs between normal and cancer tissues. We then performed an integrative analysis to explore the expression and prognostic significance of these RBPs. A total of 164 differently expressed RBPs were identified, including 40 down-regulated and 124 up-regulated RBPs. Pathway and Gene ontology (GO) analysis indicated that the differently expressed RBPs were mainly related to RNA processing, RNA metabolic process, RNA degradation, RNA transport, splicing, localization, regulation of translation, RNA binding, TGF-beta signaling pathway, mRNA surveillance pathway, and aminoacyl-tRNA biosynthesis. Survival analysis revealed that the high expression of BOP1 or GNL3 or WDR12 or DCAF13 or IGF2BP3 or IGF2BP1 were associated with poor overall survival (OS). Conversely, overexpression of KHDRBS2/SMAD predicted high OS in these patients. ROC curve analysis showed that the eight hub genes with a better diagnostic accuracy to distinguish lung adenocarcinoma. The results provided novel insights into the pathogenesis of LUAD and the development of treatment targets and prognostic molecular markers.

LncRNA KCNQ1OT1 affects cell proliferation, apoptosis and fibrosis through regulating miR-18b-5p/SORBS2 axis and NF-ĸB pathway in diabetic nephropathy

BACKGROUND

It has been reported that long non-coding RNAs (lncRNAs) play vital roles in diabetic nephropathy (DN). Our study aims to research the function of lncRNA KCNQ1OT1 in DN cells and the molecular mechanism.

METHODS

Human glomerular mesangial cells (HGMCs) and human renal glomerular endothelial cells (HRGECs) were cultured in high glucose (30 mM) condition as models of DN cells. KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) and miR-18b-5p levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The mRNA and protein levels of Sorbin and SH3 domain-containing protein 2 (SORBS2), Type IV collagen (Col-4), fibronectin (FN), transcriptional regulatory factor-beta 1 (TGF-β1), Twist, NF-κB and STAT3 were measured by qRT-PCR and western blot. Cell viability was detected by cell counting kit-8 (CCK-8) assay for selecting the proper concentration of glucose treatment. Additionally, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and flow cytometry assay were employed to determine cell proliferation and apoptosis, respectively. The targets of KCNQ1OT1 was predicted by online software and confirmed by dual-luciferase reporter assay.

RESULTS

KCNQ1OT1 and SORBS2 were elevated in DN. Both knockdown of KCNQ1OT1 and silencing of SORBS2 restrained proliferation and fibrosis and induced apoptosis in DN cells. Besides, Overexpression of SORBS2 restored the KCNQ1OT1 knockdown-mediate effects on proliferation, apoptosis and fibrosis in DN cells. In addition, miR-18b-5p served as a target of KCNQ1OT1 as well as targeted SORBS2. KCNQ1OT1 knockdown repressed NF-ĸB pathway.

CONCLUSION

KCNQ1OT1 regulated DN cells proliferation, apoptosis and fibrosis via KCNQ1OT1/miR-18b-5p/SORBS2 axis and NF-ĸB pathway.