SUMO-Activating Enzyme Subunit 1 (SAE1) Is a Promising Diagnostic Cancer Metabolism Biomarker of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most diagnosed malignancies and a leading cause of cancer-related mortality globally. This is exacerbated by its highly aggressive phenotype, and limitation in early diagnosis and effective therapies. The SUMO-activating enzyme subunit 1 (SAE1) is a component of a heterodimeric small ubiquitin-related modifier that plays a vital role in SUMOylation, a post-translational modification involving in cellular events such as regulation of transcription, cell cycle and apoptosis. Reported overexpression of SAE1 in glioma in a stage-dependent manner suggests it has a probable role in cancer initiation and progression. In this study, hypothesizing that SAE1 is implicated in HCC metastatic phenotype and poor prognosis, we analyzed the expression of SAE1 in several cancer databases and to unravel the underlying molecular mechanism of SAE1-associated hepatocarcinogenesis. Here, we demonstrated that SAE1 is over-expressed in HCC samples compared to normal liver tissue, and this observed SAE1 overexpression is stage and grade-dependent and associated with poor survival. The receiver operating characteristic analysis of SAE1 in TCGA−LIHC patients (n = 421) showed an AUC of 0.925, indicating an excellent diagnostic value of SAE1 in HCC. Our protein-protein interaction analysis for SAE1 showed that SAE1 interacted with and activated oncogenes such as PLK1, CCNB1, CDK4 and CDK1, while simultaneously inhibiting tumor suppressors including PDK4, KLF9, FOXO1 and ALDH2. Immunohistochemical staining and clinicopathological correlate analysis of SAE1 in our TMU-SHH HCC cohort (n = 54) further validated the overexpression of SAE1 in cancerous liver tissues compared with ‘normal’ paracancerous tissue, and high SAE1 expression was strongly correlated with metastasis and disease progression. The oncogenic effect of upregulated SAE1 is associated with dysregulated cancer metabolic signaling. In conclusion, the present study demonstrates that SAE1 is a targetable cancer metabolic biomarker with high potential diagnostic and prognostic implications for patients with HCC.

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SUMO-Activating Enzyme Subunit 1 (SAE1) is A Promising Diagnostic Cancer Metabolism Biomarker of Hepatocellular Carcinoma

10.21203/rs.3.rs-106307/v1 ◽

2020 ◽

Author(s):

Jiann Ruey Ong ◽

Oluwaseun Adebayo Bamodu ◽

Nguyen Viet Khang ◽

Yen-Kuang Lin ◽

Chi-Tai Yeh ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Cancer Metabolism ◽

Interaction Analysis ◽

Normal Liver ◽

Diagnostic Value ◽

Vital Role ◽

Regulation Of Transcription ◽

Dependent Manner ◽

Post Translational Modification ◽

Characteristic Analysis

Abstract Background: Hepatocellular carcinoma (HCC) is one of the most diagnosed malignancies and a leading cause of cancer-related mortality globally. This is exacerbated by its highly aggressive phenotype, and limitation in early diagnosis and effective therapies. The SUMO-activating enzyme subunit 1 (SAE1) is a component of a heterodimeric small ubiquitin-related modifier that plays a vital role in SUMOylation, a post-translational modification involving in cellular events such as regulation of transcription, cell cycle and apoptosis. Reported overexpression of SAE1 in glioma in a stage-dependent manner suggests it probable role in cancer initiation and progression. Methods: In this study, hypothesizing that SAE1 is implicated in HCC metastatic phenotype and poor prognosis, we analyzed the expression of SAE1 in several cancer databases. Results: Here, we demonstrated that SAE1 is overexpressed in HCC samples compared to normal liver tissue, and this observed SAE1 overexpression is stage and grade-dependent and associated with poor survival. The receiver operating characteristic analysis of SAE1 in TCGA-LIHC patients (n=421) showed an AUC of 0.925, indicating an excellent diagnostic value of SAE1 in HCC. Our protein-protein interaction analysis for SAE1 showed that SAE1 interacted with and activated oncogenes such as PLK1, CCNB1, CDK4 and CDK1, while simultaneously inhibiting tumor suppressors including PDK4, KLF9, FOXO1 and NEDD4. Immunohistochemical staining and clinicopathological correlate analysis of SAE1 in our TMU-SHH HCC cohort (n =54) further validated the overexpression of SAE1 in cancerous liver tissues compared with ‘normal’ paracancerous tissue, and high SAE1 expression was strongly correlated with metastasis and disease progression. Conclusion: In conclusion, the present study demonstrates that SAE1 is a targetable molecular biomarker with high potential diagnostic and prognostic implications for patients with HCC.

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The diagnostic and prognostic value of H2AFY in hepatocellular carcinoma

10.21203/rs.3.rs-17889/v2 ◽

2020 ◽

Author(s):

xuyang ma ◽

Ying Ding ◽

Li Zeng

Keyword(s):

Gene Expression ◽

Hepatocellular Carcinoma ◽

Poor Prognosis ◽

Prognostic Value ◽

Clinical Characteristics ◽

Cox Regression ◽

Normal Liver ◽

Diagnostic Value ◽

The Relationship ◽

Diagnostic And Prognostic Value

Abstract Background: The potential correlation between H2AFY (also known as MacroH2A1) and the clinical characteristics of hepatocellular carcinoma (HCC) patients was analysed through gene expression profiles and clinical data in The Cancer Genome Atlas (TCGA) database, and the diagnostic and prognostic value of H2AFY in HCC was discussed. Methods: The gene expression data of HCC and the corresponding clinical characteristics of HCC patients were downloaded from the TCGA database. The differences in H2AFY in normal liver tissues and HCC were analysed. The relationship between H2AFY and clinical characteristics was analysed by Wilcoxon signed-rank test, logistic regression and Kruskal-Wallis test. The Kaplan-Meier method and the Cox regression method were used to analyse the relationship between overall survival and clinical characteristics of the patients. An ROC curve was used to predict the diagnostic value of H2AFY in HCC. Gene set enrichment analysis (GSEA) was used to analyse the pathway enrichment of H2AFY. Result: Compared with normal liver tissues, H2AFY was significantly highly expressed in HCC. H2AFY was positively correlated with the age, clinical stage, G stage (grade) and T stage (tumor stage) of liver cancer patients. Higher H2AFY expression predicted a poor prognosis in HCC patients. Cox regression analysis suggested that H2AFY was an independent risk factor for the prognosis of HCC patients. The ROC curve suggested that H2AFY had certain diagnostic value in HCC. GSEA suggested that H2AFY was correlated with lipid metabolism and a variety of tumour pathways. Conclusion: Our study showed that H2AFY was significantly overexpressed in HCC. H2AFY may be a potential diagnostic and prognostic marker for HCC, and high expression of H2AFY predicts a poor prognosis in patients with HCC.

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Liver regeneration after radiotherapy in patients with hepatocellular carcinoma: A simple-to-use model and nomogram.

Journal of Clinical Oncology ◽

10.1200/jco.2021.39.15_suppl.e16115 ◽

2021 ◽

Vol 39 (15_suppl) ◽

pp. e16115-e16115

Author(s):

Ting-Shi Su ◽

Li-Qing Li ◽

Shi-Xiong Liang

Keyword(s):

Hepatocellular Carcinoma ◽

Risk Stratification ◽

Liver Regeneration ◽

Validation Cohort ◽

Liver Volume ◽

Normal Liver ◽

Target Area ◽

Good Prediction ◽

Characteristic Analysis ◽

Training Cohort

e16115 Background: In the past clinical practice of radiotherapy for liver cancer, liver regeneration (LR) which is beneficial to the prevention or recovery of radiation-induced liver injury, has not received enough attention. In current study, we aimed to build and validate multivariate model for liver regeneration after radiation therapy for hepatocellular carcinoma (HCC) based on data from 2 prospective studies. Methods: Thirty patients treated with preoperative downstaging radiotherapy were prospectively included in the training cohort, and 21 patients treated with postoperative adjuvant radiotherapy were included in the validation cohort. Liver regeneration was defined as an increase of more than 10% of normal liver volume in the areas of the protected hepatic segment or lobe, without Child-Pugh class decreased and tumor progression compared to pre-radiotherapy. Model and nomogram of liver regeneration after radiotherapy were developed and validated. The cut-off points of each optimal predictors were obtained using receiver-operating characteristic analysis. Risk stratification based on the cut-off point was conducted to compare the proportion of patients with liver regeneration between subgroups. Results: After radiotherapy, 12 (40%) cases in the training cohort and 13 (61.9%) cases in the validation cohort experienced liver regeneration. The model and nomogram of liver regeneration based on SVs20 (standard residual liver volume spared from at least 20 Gy) and alanine aminotransferase (ALT) showed good prediction performance (AUC = 0.759) in training cohort and performed well (AUC = 0.808) in the validation cohort. The risk stratification according to the cutoffs of SVs20 with 303.4 mL and ALT with 43 U/L demonstrated clear differentiation in risk of liver regeneration between the training(P = 0.049) and entire cohort (P = 0.032). The proportion of patients with liver regeneration decrease progressively with 88.9% in high-probability group (ALT＜43 U/L and SVs20＜303.4 mL), 60% in high-intermediate probability group (ALT ≥43 U/L and SVs20＜303.4 mL), 43.75% in low-intermediate probability group (ALT＜43 U/L and SVs20≥303.4 mL) and 33% in low- probability group (ALT≥43 U/L and SVs20≥303.4 mL). Conclusions: SVs20 and ALT are optimal predictors for liver regeneration. This simple-to-use nomogram is beneficial to the constraints of normal liver outside the radiotherapy target area and make prognosis-based decision without complex calculations. Clinical trial information: ChiCTR1800015350. [Table: see text]

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Diagnostic Test of PIVKA-II as A Tumor Marker for Hepatocellular Carcinoma (HCC)

INDONESIAN JOURNAL OF CLINICAL PATHOLOGY AND MEDICAL LABORATORY ◽

10.24293/ijcpml.v26i2.1436 ◽

2020 ◽

Vol 26 (2) ◽

Author(s):

Dwi Priyadi Djatmiko ◽

I Putu Adi Santosa ◽

Elvin Richela Lawanto ◽

Bogi Pratomo ◽

Hani Susianti

Keyword(s):

Hepatocellular Carcinoma ◽

Tumor Marker ◽

Diagnostic Test ◽

Method Comparison ◽

Normal Liver ◽

Diagnostic Value ◽

Roc Curve Analysis ◽

Healthy Control ◽

Cirrhotic Patients ◽

Sensitivity Specificity

Introduction. Alpha-Fetoprotein (AFP) is a tumor marker that has been widely used for HCC, but there has been no increased AFP in 35-45% patients with HCC. Protein induced by vitamin K absence or antagonist II (PIVKA-II) is an abnormal prothrombin secreted in HCC and is expected can be used for HCC diagnostic marker. The objective of this study was to compare serum PIVKA-II levels in the patients with HCC, cirrhosis and healthy control and determine the diagnostic value of PIVKA-II for hepatocellular carcinoma. Methods. This was a cross-section analytic observational study to identify the diagnostic value of PIVKA-II for HCC diagnosis. The diagnosis of 20 cirrhotic patients and 15 patients with HCC was established by history taking, physical examination, and additional examination according to the diagnosis criteria. A group of 12 individuals with normal liver function were used as healthy control subjects. Serum PIVKA-II levels were analyzed with immunoassay method. Comparison study used the Independent-Samples Kruskal Wallis Test. ROC curve analysis and 2x2 contingency table was used to calculate sensitivity, specificity, positive and negative predictive value (PPV and NPV).Results. The serum PIVKA-II level in the patients with HCC was significantly higher than in cirrhotic (p = 0,000) and healthy control patients (p = 0,000). Sensitivity, specificity, PPV, and NPV of PIVKA-II for diagnosis of HCC in cirrhotic patients at a cut-off value of 140.85 mAU/mL were 93.33%, 75%, 73.68%, and 93.75%, respectively (AUC = 0.87).Conclusions and Suggestions. PIVKA-II has high diagnostic value for HCC diagnosis. Diagnostic test that compare serum PIVKA-II level in any size of HCC nodules may be needed in the future.

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Diagnostic Value of Clusterin Immunostaining in Hepatocellular Carcinoma

10.21203/rs.3.rs-27056/v1 ◽

2020 ◽

Author(s):

Yuan Li ◽

Fangfang Liu ◽

Wendi Zhou ◽

Sharon Zhang ◽

Peiguo Chu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Expression Pattern ◽

Staining Pattern ◽

Hepatocellular Adenoma ◽

Normal Liver ◽

Diagnostic Value ◽

Tissue Samples ◽

Regenerative Nodules ◽

Well Differentiated ◽

Mass Lesions

Abstract Background Histologic distinction between well differentiated hepatocellular carcinoma (HCC) and benign hepatocellular mass lesions is a known challenging. Existing biomarkers are of limited diagnostic value. Our previous studies observed an enhanced canalicular expression pattern of clusterin (CLU) in HCC, which was not observed in benign hepatocellular mass lesions such as hepatocellular adenoma. The aim of this study was to further investigate its diagnostic value for HCC by examining the expression pattern of CLU in a large number of non-hepatocellular tumors, and by comparing it with two other commonly used hepatocellular markers pCEA and CD10 that also show a canalicular staining pattern in HCC.Methods Enhanced canalicular staining patterns of CLU, pCEA and CD10 were analyzed on 54 surgically resected well to moderately differentiated HCCs on whole tissue sections, of which 37 had surrounding regenerative nodules while the remaining 17 had a non-cirrhotic background. CLU immunostaining was also performed on tissue microarray sections that contained 74 HCCs (40 of which were also stained for pCEA and CD10), 55 normal liver tissue samples, and 1305 non-hepatocellular tumors from multiple organs.Results Enhanced CLU canalicular staining was observed in 70% (89/128) HCCs but not in regenerative nodules, normal liver tissues or any non-hepatocellular tumors. The sensitivity and specificity for enhanced canalicular staining pattern of CLU in HCCs were 0.70 and 1.00. This enhanced canalicular pattern was observed in only 26% and 23% HCCs for CD10 and pCEA, respectively. These results further demonstrate that the distinctive enhanced canalicular pattern of CLU is unique to HCC.Conclusions CLU is superior to pCEA and CD10 as a diagnostic immunomarker in that it can help distinguish HCC not only from non-HCC malignancies but also from benign hepatocellular mass lesions.

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Diagnostic Value of Clusterin Immunostaining in Hepatocellular Carcinoma

10.21203/rs.3.rs-27056/v3 ◽

2020 ◽

Author(s):

Yuan Li ◽

Fangfang Liu ◽

Wendi Zhou ◽

Sharon Zhang ◽

Peiguo Chu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Expression Pattern ◽

Staining Pattern ◽

Hepatocellular Adenoma ◽

Normal Liver ◽

Diagnostic Value ◽

Tissue Samples ◽

Multiple Organs ◽

Regenerative Nodules ◽

Mass Lesions

Abstract Background: Histologic distinction between well differentiated hepatocellular carcinoma (HCC) and benign hepatocellular mass lesions is a known challenging. Existing biomarkers are of limited diagnostic value. Our previous studies observed an enhanced canalicular expression pattern of clusterin (CLU) in HCC, which was not observed in benign hepatocellular mass lesions such as hepatocellular adenoma. The aim of this study was to further investigate its diagnostic value for HCC by examining the expression pattern of CLU in a large number of non-hepatocellular tumors, and by comparing it with two other commonly used hepatocellular markers pCEA and CD10 that also show a canalicular staining pattern in HCC. Methods: Enhanced canalicular staining patterns of CLU, pCEA and CD10 were analyzed on 54 surgically resected well to moderately differentiated HCCs on whole tissue sections, of which 37 had surrounding regenerative nodules while the remaining 17 had a non-cirrhotic background. CLU immunostaining was also performed on tissue microarray sections that contained 74 HCCs (40 of which were also stained for pCEA and CD10), 55 normal liver tissue samples, and 1305 non-hepatocellular tumors from multiple organs. Results: Enhanced CLU canalicular staining was observed in 70% (89/128) HCCs but not in regenerative nodules, normal liver tissues or any non-hepatocellular tumors. The sensitivity and specificity for enhanced canalicular staining pattern of CLU in HCCs were 0.70 and 1.00. This enhanced canalicular pattern was observed in only 26% and 23% HCCs for CD10 and pCEA, respectively. These results further demonstrate that the distinctive enhanced canalicular pattern of CLU is unique to HCC. Conclusions: CLU is superior to pCEA and CD10 as a diagnostic immunomarker in that it can help distinguish well to moderately differentiated HCC not only from non-HCC malignancies but also from benign hepatocellular mass lesions.

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Prognostic significance and oncogene function of cathepsin A in hepatocellular carcinoma

Scientific Reports ◽

10.1038/s41598-021-93998-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Huaxiang Wang ◽

Fengfeng Xu ◽

Fang Yang ◽

Lizhi Lv ◽

Yi Jiang

Keyword(s):

Hepatocellular Carcinoma ◽

Oxidative Phosphorylation ◽

Prognostic Significance ◽

Enrichment Analysis ◽

Normal Liver ◽

Diagnostic Value ◽

Gene Set Enrichment Analysis ◽

The Cancer Genome Atlas ◽

Clinical Value ◽

Lysosomal Protease

AbstractCathepsin A (CTSA) is a lysosomal protease that regulates galactoside metabolism. The previous study has shown CTSA is abnormally expressed in various types of cancer. However, rarely the previous study has addressed the role of CTSA in hepatocellular carcinoma (HCC) and its prognostic value. To study the clinical value and potential function of CTSA in HCC, datasets from the Cancer Genome Atlas (TCGA) database and a 136 HCC patient cohort were analyzed. CTSA expression was found to be significantly higher in HCC patients compared with normal liver tissues, which was supported by immunohistochemistry (IHC) validation. Both gene ontology (GO) and The Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses demonstrated that CTSA co-expressed genes were involved in ATP hydrolysis coupled proton transport, carbohydrate metabolic process, lysosome organization, oxidative phosphorylation, other glycan degradation, etc. Survival analysis showed a significant reduction both in overall survival (OS) and recurrence-free survival (RFS) of patients with high CTSA expression from both the TCGA HCC cohort and 136 patients with the HCC cohort. Furthermore, CTSA overexpression has diagnostic value in distinguishing between HCC and normal liver tissue [Area under curve (AUC) = 0.864]. Moreover, Gene set enrichment analysis (GSEA) showed that CTSA expression correlated with the oxidative phosphorylation, proteasome, and lysosome, etc. in HCC tissues. These findings demonstrate that CTSA may as a potential diagnostic and prognostic biomarker in HCC.

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Diagnostic value of clusterin immunostaining in hepatocellular carcinoma

Diagnostic Pathology ◽

10.1186/s13000-020-01041-8 ◽

2020 ◽

Vol 15 (1) ◽

Author(s):

Yuan Li ◽

Fangfang Liu ◽

Wendi Zhou ◽

Sharon Zhang ◽

Peiguo Chu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Expression Pattern ◽

Staining Pattern ◽

Hepatocellular Adenoma ◽

Normal Liver ◽

Diagnostic Value ◽

Tissue Samples ◽

Multiple Organs ◽

Regenerative Nodules ◽

Mass Lesions

Abstract Background Histologic distinction between well differentiated hepatocellular carcinoma (HCC) and benign hepatocellular mass lesions is a known challenge. Existing biomarkers are of limited diagnostic value. Our previous studies observed an enhanced canalicular expression pattern of clusterin (CLU) in HCC, which was not observed in benign hepatocellular mass lesions such as hepatocellular adenoma. The aim of this study was to further investigate its diagnostic value for HCC by examining the expression pattern of CLU in a large number of non-hepatocellular tumors, and by comparing it with two other commonly used hepatocellular markers pCEA and CD10 that also show a canalicular staining pattern in HCC. Methods Enhanced canalicular staining patterns of CLU, pCEA and CD10 were analyzed on 54 surgically resected well to moderately differentiated HCCs on whole tissue sections, of which 37 had surrounding regenerative nodules while the remaining 17 had a non-cirrhotic background. CLU immunostaining was also performed on tissue microarray sections that contained 74 HCCs (40 of which were also stained for pCEA and CD10), 55 normal liver tissue samples, and 1305 non-hepatocellular tumors from multiple organs. Results Enhanced CLU canalicular staining was observed in 70% (89/128) HCCs but not in regenerative nodules, normal liver tissues or any non-hepatocellular tumors. The sensitivity and specificity for enhanced canalicular staining pattern of CLU in HCCs were 0.70 and 1.00. This enhanced canalicular pattern was observed in only 26 and 23% HCCs for CD10 and pCEA, respectively. These results further demonstrate that the distinctive enhanced canalicular pattern of CLU is unique to HCC. Conclusions CLU is superior to pCEA and CD10 as a diagnostic immunomarker in that it can help distinguish well to moderately differentiated HCC not only from non-HCC malignancies but also from benign hepatocellular mass lesions.

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Diagnostic Value of Clusterin Immunostaining in Hepatocellular Carcinoma

10.21203/rs.3.rs-27056/v2 ◽

2020 ◽

Author(s):

Yuan Li ◽

Fangfang Liu ◽

Wendi Zhou ◽

Sharon Zhang ◽

Peiguo Chu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Expression Pattern ◽

Staining Pattern ◽

Hepatocellular Adenoma ◽

Normal Liver ◽

Diagnostic Value ◽

Tissue Samples ◽

Multiple Organs ◽

Regenerative Nodules ◽

Mass Lesions

Abstract Background Histologic distinction between well differentiated hepatocellular carcinoma (HCC) and benign hepatocellular mass lesions is a known challenging. Existing biomarkers are of limited diagnostic value. Our previous studies observed an enhanced canalicular expression pattern of clusterin (CLU) in HCC, which was not observed in benign hepatocellular mass lesions such as hepatocellular adenoma. The aim of this study was to further investigate its diagnostic value for HCC by examining the expression pattern of CLU in a large number of non-hepatocellular tumors, and by comparing it with two other commonly used hepatocellular markers pCEA and CD10 that also show a canalicular staining pattern in HCC. Methods Enhanced canalicular staining patterns of CLU, pCEA and CD10 were analyzed on 54 surgically resected well to moderately differentiated HCCs on whole tissue sections, of which 37 had surrounding regenerative nodules while the remaining 17 had a non-cirrhotic background. CLU immunostaining was also performed on tissue microarray sections that contained 74 HCCs (40 of which were also stained for pCEA and CD10), 55 normal liver tissue samples, and 1305 non-hepatocellular tumors from multiple organs. Results Enhanced CLU canalicular staining was observed in 70% (89/128) HCCs but not in regenerative nodules, normal liver tissues or any non-hepatocellular tumors. The sensitivity and specificity for enhanced canalicular staining pattern of CLU in HCCs were 0.70 and 1.00. This enhanced canalicular pattern was observed in only 26% and 23% HCCs for CD10 and pCEA, respectively. These results further demonstrate that the distinctive enhanced canalicular pattern of CLU is unique to HCC. Conclusions CLU is superior to pCEA and CD10 as a diagnostic immunomarker in that it can help distinguish well to moderately differentiated HCC not only from non-HCC malignancies but also from benign hepatocellular mass lesions.

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RANBP2 Activates O-GlcNAcylation through Inducing CEBPα-Dependent OGA Downregulation to Promote Hepatocellular Carcinoma Malignant Phenotypes

Cancers ◽

10.3390/cancers13143475 ◽

2021 ◽

Vol 13 (14) ◽

pp. 3475

Author(s):

Xiaoming Liu ◽

Xingyu Chen ◽

Mengqing Xiao ◽

Yuxing Zhu ◽

Renjie Gong ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Binding Protein ◽

Dependent Manner ◽

Post Translational Modification ◽

E3 Ligases ◽

Enhancer Binding Protein ◽

Underlying Mechanisms ◽

Glcnac Transferase

O-GlcNAcylation is an important post-translational modification (PTM) jointly controlled by O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). Aberrant hyper-O-GlcNAcylation is reported to yield hepatocellular carcinoma (HCC) malignancy, but the underlying mechanisms of the OGT/OGA imbalance responsible for HCC tumorigenesis remain largely unknown. Here, we report that RAN-binding protein 2 (RANBP2), one of the small ubiquitin-like modifier (SUMO) E3 ligases, contributed to malignant phenotypes in HCC. RANBP2 was found to facilitate CCAAT/enhancer-binding protein alpha (CEBPα) SUMOylation and degradation by direct interplay with CEBPα. As a transcriptional factor, CEBPα was verified to augment OGA transcription, and further experiments demonstrated that RANBP2 enhanced the O-GlcNAc level by downregulating OGA transcription while not affecting OGT expression. Importantly, we provided in vitro and in vivo evidence of HCC malignant phenotypes that RANBP2 triggered through an imbalance of OGT/OGA and subsequent higher O-GlcNAcylation events for oncogenic proteins such as peroxisome proliferative-activated receptor gamma coactivator 1 alpha (PGC1α) in a CEBPα-dependent manner. Altogether, our results show a novel molecular mechanism whereby RANBP2 regulates its function through CEBPα-dependent OGA downregulation to induce a global change in the hyper-O-GlcNAcylation of genes, such as PGC1α, encouraging the further study of promising implications for HCC therapy.

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