Identification of prognostic biomarkers for patients with hepatocellular carcinoma after hepatectomy
- Authors:
- Published online on: January 3, 2019 https://doi.org/10.3892/or.2019.6953
- Pages: 1586-1602
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Copyright: © Wang et al. This is an open access article distributed under the terms of Creative Commons Attribution License.
Abstract
Introduction
Liver cancer is more common in men than in women, and is the second leading cause of cancer-associated mortality worldwide in men living in less developed countries (1). It is estimated that ~50% of newly diagnosed cancer cases and mortalities globally occurred in China alone in 2012, which equates to approximately 391,250 new liver cancer cases and 372,750 mortalities (1). Hepatocellular carcinoma (HCC) accounts for the majority (70–90%) of primary liver cancer cases worldwide (2). Previous epidemiological surveys have revealed that chronic hepatitis B or C viral infection, cirrhosis, exposure to aflatoxin B1, obesity, chronic alcohol consumption and diabetes mellitus, as well as metabolic abnormalities including haemochromatosis and α1-antitrypsin deficiency, are common and significant risk factors for HCC development (3–5). Furthermore, recent studies indicate that approximately 1,000,000 new HCC cases are diagnosed each year worldwide, with the same incidence and morbidity rate, indicating that HCC diagnosis is typically at the advanced stage and prognosis remains poor (6,7). Despite advances in diagnosis, prevention and treatment, including ultrasonography, multiphase computerized tomography, magnetic resonance imaging, surgical resection, liver transplantation, transarterial chemoembolization, radiofrequency ablation and transarterial radiation, percutaneous ablation and systemic therapy, the prognosis for HCC patients remains unsatisfactory (8). The 5-year relative survival rate is approximately 7% (9). Therefore, identification of novel biomarkers for the early diagnosis of HCC is vital and may improve HCC prognosis.
At present, many reports have focused on the identification of prognosis-associated biomarkers The role of astrocytic phosphoprotein PEA-15 in HCC has been evaluated and may be a novel target for HCC treatment, as well as a predictive biomarker for HCC patient prognosis (10). Furthermore, it has been suggested that CKLF-like MARVEL transmembrane domain-containing protein 5 may function as a tumor suppressor in human HCC and represent a valuable therapeutic target (11). microRNA (miR)-182-5p is recognized as a potential predictive biomarker for the early recurrence of HCC (12). Currently, DNA microarray approach has been used to investigate the genetic features of HCC in molecular biology (13). Accumulating evidence regarding gene expression in HCC has demonstrated that a variety of differentially expressed genes (DEGs) may be involved in the process of hepatocarcinogenesis (14). The combination of microarray techniques and bioinformatic analysis makes it conceivable to use DEGs in one or more chips to detect potential predictive biomarkers for several types of malignancies (15). Therefore, the present study focused on DEGs in microarrays and aimed to identify potential predictive biomarkers for patients with HCC.
Materials and methods
Data collection and processing
GEO2R (www.ncbi.nlm.nih.gov/geo/geo2r/) was initially used to identify DEGs in the GSE36376 gene expression profile in the Gene Expression Omnibus (GEO) database (16). The GSE36376 dataset (www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE36376) is embedded in the platform GPL10558 (Illumina HumanHT-12 v4 Expression Beadchip) and includes 240 tumor tissues and 193 adjacent non-tumor tissues of two gene expression by array sets: A training set and validation set (17).
Next, DEGs from the GSE36376 profile were acquired using the GEO2R tool with the criteria of |log fold change|≥2 and P≤0.05. Furthermore, the Cytoscape software (version 3.6.0) plugin, CentiScaPe (version 2.2), was employed to identify the top 10 hub genes in these DEGs on the basis of the following centralities: degree, betweenness and closeness (18).
Hub gene expression, survival and stratified analysis
The expression levels of 10 hub genes in multiple organs, as well as in tumor and non-tumor tissues were obtained from the GTEx portal (www.gtexportal.org/home) and the Gene Expression Profiling Interactive Analysis (GEPIA; gepia.cancer-pku.cn/index.html) server (19). Protein expression levels of the hub genes in liver tissue were obtained from The Human Protein Atlas (www.proteinatlas.org) (20). A co-expression matrix was constructed using R (version 3.5.0; www.r-project.org) to show Pearson correlations between two of these genes.
In addition, hub genes were further analyzed for their prognostic values using The Cancer Genome Atlas database (cancergenome.nih.gov/). The clinical characteristics of 360 HCC patients, including age, sex, race and tumor stage, were obtained and used in the analysis. Gene expression data were downloaded from the OncoLnc website (www.oncolnc.org) at median cut off. In addition, clinical data with statistically significant P-values (≤0.05) were adjusted for further analysis to identify prognosis-associated genes. For the above identified genes, clinical data were stratified for further analysis.
Hub gene mutational and transcriptional analysis
The mutation status of hub genes using the cBioPortal website (www.cbioportal.org/) (21,22). Furthermore, transcripts per million (TPM) of the hub genes in liver tissues were analyzed to identify transcription levels at the log scale [Log2 (TPM+1)] using the GEPIA website (gepia.cancer-pku.cn/index.html/) (19).
Construction of risk score model and nomogram
A risk score model was constructed based on the expression levels of prognosis-associated genes and the contribution coefficient (β) of the multivariate Cox proportional hazards regression model. The formula of the model was as follows: risk score=expression of gene1 × β1 of gene1 + expression of gene2 × β2 of gene2 + … + expression of genen × βn of genen. The risk score was then divided into high and low risk groups with the same cut-off criteria of gene expression. A Kaplan-Meier survival curve was drawn to predict patient survival. Prognostic receiver operating characteristic (ROC) curves were then created at 1–5 years.
A nomogram was also constructed based on seven prognosis-associated hub genes, clinical factors and tumor stage, to obtain patient survival at 1, 3 and 5 years. The contribution of each factor was limited to a maximum of 100 points.
Gene-gene and protein-protein interactions (PPI) network construction and functional enrichment analysis
To identify the biological processes and metabolic pathways of these hub genes, enrichment analysis of Gene Ontology (GO) was performed, including biological process (BP), cellular component (CC), and molecular function (MF), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways using The Database for Annotation, Visualization and Integrated Discovery (DAVID; david.ncifcrf.gov/) (15,23). In addition, visualized GO results were presented by the Cytoscape BinGO plugin version 3.6.0 (18,24). Gene-gene interaction networks were constructed using the GeneMANIA plugin (version 3.4.1) in Cytoscape software version 3.6.0 (25). The PPI network depicted interactions among these proteins and was constructed using the Search Tool for the Retrieval of Interacting Genes website (string-db.org/cgi/input.pl) (26).
Statistical analysis
Kaplan-Meier survival analysis by log rank test was used to calculate the median survival time (MST). Univariate and multivariate Cox proportional hazards models were used to calculate the hazard ratio (HR) and 95% confidence interval (CI). P≤0.05 was considered to indicate a statistically significant difference. Box plots by unpaired t-test, survival curves and ROC curves including area under the curve (AUC) were produced using GraphPad version 7.0 (GraphPad Software, Inc., La Jolla, CA, USA). Statistical analysis was performed using SPSS software version 16.0 (SPPS, Inc., Chicago, IL, USA).
Results
Processing of DEGs and hub genes
A total of 71 DEGs were obtained from the GSE36376 dataset and the top 10 hub genes were identified. These 10 hub genes included cytochrome P450 family 2 subfamily E member 1 (CYP2E1), tyrosine aminotransferase (TAT), cytochrome P450 family 2 subfamily A member 6 (CYP2A6), cytochrome P450 family 8 subfamily B member 1 (CYP8B1), cytochrome P450 family 2 subfamily C member 9 (CYP2C9), hydroxysteroid 11-β dehydrogenase 1 (HSD11B1), hydroxysteroid 17-β dehydrogenase 13 (HSD17B13), solute carrier family 22 member 1 (SLC22A1), cytochrome p450 family 2 subfamily C member 8 (CYP2C8) and alcohol dehydrogenase 4 (class II), pi polypeptide (ADH4). Detailed results are shown in Table I.
Analysis of hub gene expression, mutation and transcription
Hub gene expression in tumor tissues was downregulated compared with normal tissues in all cases (Fig. 1). However, only CYP2A6, CYP2C8, CYP2E1, HSD17B13 and SLC22A1 had a significant alteration in expression (P<0.05). Tissue expression data indicated that all of the hub genes were highly expressed in liver tissue (Fig. 2). Mutation analysis of hub genes revealed that mutations were present in different ratios (Fig. 3A). At 11%, HSD11B1 was the most significant in terms of mutation ratio, of which the majority were amplification mutations. Transcriptional analysis (Fig. 3B) demonstrated that all hub genes were differentially transcribed in tumor and normal tissues. Furthermore, normal tissues had consistently high TPM in the 10 hub genes. Detailed results are shown in Fig. 3.
Protein expression data indicated that eight proteins were highly expressed in liver tissue, excluding TAT and CYP8B1 (data not shown; Fig. 4), which was similar to the tissue expression results.
Demographic and clinicopathological characteristics
A total of 360 HCC patients were included in the dataset. Survival analysis indicated that tumor stage showed statistical significance (log-rank P<0.0001), but all other factors were not significant (log-rank P>0.05; Table II).
Expression levels and survival analysis of hub genes
In the univariate survival analysis, ADH4, CYP2C8, CYP2C9, CYP2E1, CYP8B1, HSD17B13, SLC22A1 and TAT were significant (P≤0.05; Table III and Fig. 5). Following adjustment for tumor stage, ADH4, CYP2C8, CYP2C9, CYP8B1, SLC22A1, TAT and HSD17B13 were significant (P≤0.05; Table III) while CYP2A6, CYP2E1, HSD11B1 were not significant (P>0.05). All hub genes were significantly different when comparing high and low expression levels (P<0.0001; Fig. 6A).
Stratified analysis of prognosis-associated genes
In the stratification of tumor stage, high expression levels of CYP2C8, CYP2C9, SLC22A1, TAT and HSD17B13 had tumor suppressor roles in stages I and II (P≤0.05) while high expression levels of ADH4, CYP2C8, CYP8B1, SLC22A1, TAT and HSD17B13 had tumor suppressor roles in stages III and IV (P≤0.05). Detailed results are presented in Tables IV and V.
Table IV.Stratified analysis of HSD17B13, SLC22A1 and TAT for HCC patients (n=360) in terms of prognosis. |
Table V.Stratified analysis of ADH4, CYP2C8, CYP2C9 and CYP8B1 for HCC patients (n=360) in terms of prognosis. |
Hub gene co-expression and Pearson correlation analysis
The majority of hub genes showed significant Pearson correlations with other genes. For example, CYP2E1 was positively correlated with CYP2C8, CYP2C9, CYP8B1, ADH4 and HSD11B1, and negatively correlated with CYP2A6 and HSD17B13. Detailed results are presented in Fig. 6B.
In the PPI network, most of the hub genes exhibited complicated interactive co-expression relationships, with the exception of HSD11B1, which was co-expressed with HSD17B13 alone (Fig. 6C). In the gene-gene interaction network, each gene was co-expressed with at least two other genes (Fig. 6D).
Risk score model and nomogram construction
A risk score model was constructed using the aforementioned formula, which contained risk score ranking, survival status and heat maps of gene expressions (Fig. 7A). The Kaplan-Meier plot revealed that the percent survival difference between the low and high risk groups was significant (Fig. 7B). ROC curves were then constructed to evaluate the prognostic values of the model. In the 1–5 year ROC curves, all AUCs were above 0.6 (Fig. 7C), which shows that this model was useful for prognosis prediction. In the comparison of high and low risk score groups, all of the comparisons showed significant P-values (all P<0.001; Fig. 7D).
The contributions of each factor were present in the nomogram (Fig. 8). In detail, tumor stages III and IV showed the maximum 100 points. Unlike the other genes, high expression levels of CYP8B1 had a high number of points. High points typically indicated low survival probability at 1, 3 and 5 years. As expected, there was a high probability of survival prediction at 1 year compared with 5 years.
Hub genes enrichment analysis
GO analysis revealed that genes were significantly enriched in the terms such as ‘oxidation-reduction process’, the ‘epoxygenase P450 pathway’, ‘metbolism of xenobiotics by cytochrome P450’, ‘chemical carcinogenesis’, ‘drug metabolic processes’ and ‘organelle membranes’ (Fig. 9).
BP terms, including ‘exogenous drug catabolic process’, ‘drug catabolic process’, ‘secondary metabolic process’ and ‘oxidation reduction’, were significantly enriched (Fig. 10). In CC terms, ‘subsynaptic reticulum’, ‘endoplasmic reticulum’, ‘microsome’ and ‘vesicular fraction’, were enriched (Fig. 11). ‘Oxygen binding’, ‘iron ion binding’, ‘heme binding’, ‘electron carrier activity’ and ‘oxidoreductase activity’, were enriched in terms of MF (Fig. 12).
Discussion
In the present study, DEGs were analyzed in microarrays to identify hub genes. The top 10 hub genes in the GSE36376 dataset were examined for their prognostic prediction value in HCC. A total of seven genes, including ADH4, CYP2C8, CYP2C9, CYP8B1, SLC22A1, TAT and HSD17B13, were identified as potential prognostic biomarkers. In addition, high expression levels of these hub genes were associated with tumor suppressing roles in HCC. Stratified analysis of clinical factors further revealed their prognostic values in subgroups. A risk score model for patient survival was constructed and evaluated, which confirmed its value for assessing prognosis. A nomogram was created to identify the degree of the contribution made by each factor. Enrichment analysis of the hub genes highlighted the metabolic pathways and biological processes that the hub genes were involved in, which may provide clues into the exact mechanisms of HCC development.
Valuable data in gene microarrays may be lost due to potentially unpredictable problems with the samples when the results of a single piece of research are analyzed (27). Furthermore, using a Student's t-test to analyze microarray data has several limitations (27). Small sample sizes may lead to unreliable variance estimation, leading to a high false-positive rate, while some significant and reliable differences in expression may be missed (28). However, in the present study, analyzing microarray data from a study with a large sample size, allowed the acquisition of potentially useful information for further analysis. In total, 433 samples from the GSE36376 dataset were analyzed to obtain DEGs, in order to determine potential serum biomarkers for HCC diagnosis and prognosis. Focused on an Asian population, the present study also searched for DEGs using the GEO2R online resource. The top 10 hub genes in these DEGs were selected for further analysis, and seven of these hub genes, ADH4, CYP2C8, CYP2C9, CYP8B1, SLC22A1, TAT and HSD17B13, were confirmed to have prognostic value in HCC.
The human ADH4 enzyme is encoded by the ADH4 gene, which maps to 4q22 within the ADH gene cluster (29). Previous studies have revealed that a ADH4 gene variant confers risk for alcohol dependence (AD) and related traits in European Americans and African Americans (29). Edenberg et al (30) reported that 16 single nucleotide polymorphisms (SNP) of ADH4, including rs2226896, are associated with AD, in an independent collaborative study on the genetics of alcoholism. Edenberg et al (31) showed that ADH4 promoter variant −75A/C (rs800759), which could alter ADH4 enzyme expression levels significantly, as well as the 159A/G variant were significantly linked to AD in European Americans and African Americans in a Brazilian population (31). Previous studies have reported that ADH4 may be associated with cluster headaches and personality traits such as agreeableness and extraversion (32,33). In addition, polymorphisms in the ADH4 gene are associated with a decreased risk of ovarian cancer (34) and an increased risk of upper aerodigestive tract cancer (35), which suggests that the ADH4 may be involved in tumorigenesis. Wei et al (36) found that ADH4 mRNA expression in HCC is significantly lower than that in non-cancerous tissue, and ADH4 protein expression is also reduced in HCC, which indicates that ADH4 may serve as a tumor suppressor. These findings are consistent with the results of the present study, where ADH4 was identified as a potential prognostic biomarker for HCC.
The CYP2 family contains many subfamilies, including CYP2A, CYP2B, CYP2C, CYP2D, CYP2E and CYP2F (37). CYP2C8 and CYP2C9 are members of the CYP2C subfamily that are localized in a single gene locus on chromosome 10 (38,39). CYP2C8 shares sequence homology with CYP2C9, that metabolizes several drugs including analgesics (40), antidiabetic and cholesterol-lowering drugs (41). CYP2C9 metabolizes the majority of angiotensin II type 1 receptor blockers (42) and neurological drugs (43). In addition, CYP2C8 has been associated with an increased risk of essential hypertension and coronary artery disease in Bulgarian patients (44), anemia (45), vascular inflammatory disease (46) and breast cancer (47). It has been reported that CYP2C9 downregulation by miR-128-3p is associated with HCC (48). In addition, we have previously reported that analysis of CYP2C8 and CYP2C9 expression in combination is better than analyzing them in isolation (37).
CYP8B1 is predominantly expressed in hepatocytes in a homogenous pattern (49) and is involved in bile acid synthesis of bile acids (50). Overexpression of CYP8B1 alone or in combination with CYP7A1, but not of CYP7A1 alone, reverses obeticholic acid-induced alterations in bile acid levels (taurocholic acid), bile acid composition (taurocholic acid and α/β-muricholic acids) and cholesterol absorption (51). The SNP rs3732860 in the 3′-untranslated region of the CYP8B1 gene is linked to gallstone disease risk in the Chinese Han population (52,53). However, the function of CYP8B1 in cancer remains elusive. The present study indicated that CYP8B1 may serve as a potential biomarker for HCC, and may be involved in tumor initiation and development.
SLC22A1 has the ability to encode solute carrier family 22 member 1, which is not only an uptake transporter but also has a predictive value for the molecular response to imatinib mesylate therapy (54). Patients who experience a major molecular response have higher SLC22A1 expression compared with those without a major molecular response (55). SLC22A1-ABCB1 haplotype profiles can predict imatinib pharmacokinetics in Asian patients with chronic myeloid leukemia (56). Indirect SLC22A1 gene upregulation by dexamethasone may be caused by glucocorticoid receptor-induced hepatocyte nuclear factor-4α expression in primary human hepatocytes, but not in hepatocyte-derived tumor cell lines (57). HCC and cholangiocarcinoma development is typically accompanied by decreased SLC22A1 expression, which may significantly alter the ability of sorafenib to reach active intracellular concentrations in these tumors (58). Downregulated SLC22A1 expression is associated with tumor progression and decreased survival in patients with cholangiocellular carcinoma (59). However, to the best of our knowledge, the relationship between SLC22A1 and HCC patient prognosis has not been reported. The present study demonstrated that SLC22A1 may be a predictive biomarker for HCC.
TAT is associated with the catalyzing the transamination of tyrosine and other aromatic amino acids and plays a role in recovery from tyrosinemia type II, hepatitis and hepatic carcinoma (60). Deficiency of TAT causes marked hypertyrosinemia, which leads to painful palmoplantar hyperkeratosis, pseudodendritic keratitis, and variable mental retardation (61). Recurrent mutation of the TAT gene has been reported in those affected by Richner-Hanhart syndrome (62). Fu et al (63) reported that downregulation of TAT at a frequently deleted region, 16q22, contributes to the pathogenesis of HCC, and it was demonstrated that TAT is a novel tumor suppressor gene. This finding is consistent with the results of the present study, and may be used as an effective serum biomarker for HCC.
Su et al (64) reported that HSD17B13 is upregulated in the livers of patients with non-alcoholic fatty liver disease. HSD17B13 expression is localized to liquid droplets (65). In addition, Chen et al (66) reported that HSD17B13 is downregulated in HCC, and has a tumor suppressor role via inhibition of HCC progression and recurrence (66). This finding is in accordance with the results of the present study, where it was concluded that HSD17B13 may serve as a potential predictive biomarker for HCC.
In regards to metabolic pathways, our previous study demonstrated that the CYP2C subfamily members are involved in chemical carcinogenesis (37). The formation of DNA adducts, dG-C8-IQ, dG-N-IQ, dG-C8-MeIQx and dG-N-MeIQx, may induce liver, colon lung and breast cancer tumorigenesis (37). The present study found that the identified hub genes were also enriched in chemical carcinogenesis. Additionally, gene were enriched in ‘drug metabolism-cytochrome P450’, ‘metabolism of xenobiotics by cytochrome P450’, ‘retinol metabolism’, ‘linoleic acid metabolism’, ‘arachidonic acid metabolism’, ‘tyrosine metabolism’, and ‘steroid hormone biosynthesis’. These metabolic processes and pathways provide evidence that the hub genes may be involved in hepatocarcinogenesis.
There are some limitations to the present study. First, larger samples that include other populations are required to validate the findings of the present study. Second, an increased number of valid clinical factors, such as race, drinking status, smoking status, cirrhosis, Barcelona-Clinic liver cancer staging, hepatitis infection status, antiviral therapy, α-fetoprotein levels and microvascular invasion, should be included in the analysis. Third, functional validation in a well-designed clinical trial is required to examine the biological behavior of prognosis-associated genes on HCC initiation and progression. As the present study explored the potential prognostic biomarkers for HCC, the identification and clinical significance of targeted drugs was not investigated in the present study. Thus, it is crucial to focus future studies on these topics.
The present study indicated that low gene expression of ADH4, CYP2C8, CYP2C9, CYP8B1, SLC22A1, TAT and HSD17B13 are predictors of poor prognosis in HCC. Further functional trials and identification of targeted drugs for these hub genes is warranted to determine clinical application. In detail, trials in vivo and in vitro should be conducted to explore biological behavior, such as invasion, metastasis and proliferation ability. Then, the influence potential drugs on their target genes should be validated, to determine whether targeted overexpression of these genes improve HCC prognosis.
Acknowledgements
The authors would like to acknowledge the laboratory equipment and platform support provided by the Key Laboratory of Early Prevention and Treatment for Regional High-Incidence-Tumor (Guangxi Medical University; Ministry of Education, Nanning, China). The authors would also like to acknowledge the helpful comments on this article received from our reviewers.
Funding
The present study was supported in part by the National Nature Science Foundation of China (grant nos. 81560535, 81072321, 30760243, 30460143 and 30560133), the 2009 Program for New Century Excellent Talents in University, Guangxi Nature Sciences Foundation (grant no. GuiKeGong 1104003A-7), the Guangxi Health Ministry Medicine Grant (grant no. Key-Scientific Research-Grant Z201018), the Self-Raised Scientific Research Fund of the Health and Family Planning Commission of Guangxi Zhuang Autonomous Region (grant no. Z2016318), the Basic Ability Improvement Project for Middle-aged and Young Teachers in Guangxi Colleges and Universities (grant no. 2018KY0110), Innovation Project of Guangxi Graduate Education (grant no. JGY2018037) and the Research Institute of Innovative Think-tank in Guangxi Medical University (The gene-environment interaction in hepatocarcinogenesis in Guangxi HCCs and its translational applications in the HCC prevention).
Availability of data and materials
The datasets analyzed during the current study are available from the corresponding author on reasonable request.
Authors' contributions
XW and TP designed the study. XL, CY, TY, LY, CH, GZ, KH, XZe, ZL, XZh, WQ, HS, XY and TP conducted the study and analyzed the data. XW wrote the manuscript and TP revised the manuscript. All authors read and approved the manuscript and agree to be accountable for all aspects of the research in ensuring that the accuracy or integrity of any part of the work are appropriately investigated and resolved.
Ethics approval and consent to participate
Not applicable.
Patient consent for publication
Not applicable.
Competing interests
The authors declare that they have no competing interests.
Glossary
Abbreviations
Abbreviations:
HCC |
hepatocellular carcinoma |
GEO |
Gene Expression Omnibus |
DEG |
differentially expressed gene |
PPI |
protein-protein interaction |
GEPIA |
Gene Expression Profiling Interactive Analysis |
ROC |
receiver operating characteristic |
AUC |
area under the curve |
HR |
hazard ratio |
CI |
confidence interval |
MST |
median survival time |
GO |
Gene Ontology |
BP |
biological process |
CC |
cellular component |
MF |
molecular function |
KEGG |
Kyoto Encyclopedia of Genes and Genomes |
DAVID |
Database for Annotation, Visualization and Integrated Discovery |
References
Torre LA, Bray F, Siegel RL, Ferlay J, Lortet-Tieulent J and Jemal A: Global cancer statistics, 2012. CA Cancer J Clin. 65:87–108. 2015. View Article : Google Scholar : PubMed/NCBI | |
Kolonel LN and Wilkens LR: Migrant studies. Cancer Epidemiology and Prevention. Schottenfeld D and Fraumeni JF Jr: 3rd. Oxford University Press, Inc.; New York, NY: pp. 189–201. 2006, View Article : Google Scholar | |
Kgatle MM, Setshedi M and Hairwadzi HN: Hepatoepigenetic alterations in viral and nonviral-induced hepatocellular carcinoma. Biomed Res Int 2016. 39564852016. | |
Marotta F, Vangieri B, Cecere A and Gattoni A: The pathogenesis of hepatocellular carcinoma is multifactorial event. Novel immunological treatment in prospect. Clin Ter. 155:187–199. 2004.PubMed/NCBI | |
Coleman WB: Mechanisms of human hepatocarcinogenesis. Curr Mol Med. 3:573–388. 2003. View Article : Google Scholar : PubMed/NCBI | |
Dominguez-Malagón H and Gaytan-Graham S: Hepatocellular carcinoma: An update. Ultrastruct Pathol. 25:497–516. 2001. View Article : Google Scholar : PubMed/NCBI | |
Chen G, Wang D, Zhao X, Cao J, Zhao Y, Wang F, Bai J, Luo D and Li L: miR-155-5p modulates malignant behaviors of hepatocellular carcinoma by directly targeting CTHRC1 and indirectly regulating GSK-3β-involved Wnt/β-catenin signaling. Cancer Cell Int. 17:1182017. View Article : Google Scholar : PubMed/NCBI | |
Balogh J, Victor D III, Asham EH, Burroughs SG, Boktour M, Saharia A, Li X, Ghobrial RM and Monsour HP Jr: Hepatocellular carcinoma: A review. J Hepatocell Carcinoma. 3:41–53. 2016. View Article : Google Scholar : PubMed/NCBI | |
Tien AJ, Chien CY, Chen YH, Lin LC and Chien CT: fruiting bodies of antrodia cinnamomea and its active triterpenoid, antcin K, ameliorates N-nitrosodiethylamine-induced hepatic inflammation, fibrosis and carcinogenesis in rats. Am J Chin Med. 45:173–198. 2017. View Article : Google Scholar : PubMed/NCBI | |
Quintavalle C, Hindupur SK, Quagliata L, Pallante P, Nigro C, Condorelli G, Andersen JB, Tagscherer KE, Roth W, Beguinot F, et al: Phosphoprotein enriched in diabetes (PED/PEA15) promotes migration in hepatocellular carcinoma and confers resistance to sorafenib. Cell Death Dis. 8:e31382017. View Article : Google Scholar : PubMed/NCBI | |
Xu G and Dang C: CMTM5 is downregulated and suppresses tumour growth in hepatocellular carcinoma through regulating PI3K-AKT signalling. Cancer Cell Int. 17:1132017. View Article : Google Scholar : PubMed/NCBI | |
Cao MQ, You AB, Zhu XD, Zhang W, Zhang YY, Zhang SZ, Zhang KW, Cai H, Shi WK, Li XL, et al: miR-182-5p promotes hepatocellular carcinoma progression by repressing FOXO3a. J Hematol Oncol. 11:122018. View Article : Google Scholar : PubMed/NCBI | |
Maass T, Sfakianakis I, Staib F, Krupp M, Galle PR and Teufel A: Microarray-based gene expression analysis of hepatocellular carcinoma. Curr Genomics. 11:261–268. 2010. View Article : Google Scholar : PubMed/NCBI | |
Fu Q, Yang F, Zhao J, Yang X, Xiang T, Huai G, Zhang J, Wei L, Deng S and Yang H: Bioinformatical identification of key pathways and genes in human hepatocellular carcinoma after CSN5 depletion. Cell Signal. 49:79–86. 2018. View Article : Google Scholar : PubMed/NCBI | |
Huang da W, Sherman BT and Lempicki RA: Bioinformatics enrichment tools: Paths toward the comprehensive functional analysis of large gene lists. Nucleic Acids Res. 37:1–13. 2009. View Article : Google Scholar : PubMed/NCBI | |
Davis S and Meltzer PS: GEOquery: A bridge between the gene expression omnibus (GEO) and BioConductor. Bioinformatics. 23:1846–1847. 2007. View Article : Google Scholar : PubMed/NCBI | |
Lim HY, Sohn I, Deng S, Lee J, Jung SH, Mao M, Xu J, Wang K, Shi S, Joh JW, et al: Prediction of disease-free survival in hepatocellular carcinoma by gene expression profiling. Ann Surg Oncol. 20:3747–3753. 2013. View Article : Google Scholar : PubMed/NCBI | |
Shannon P, Markiel A, Ozier O, Baliga NS, Wang JT, Ramage D, Amin N, Schwikowski B and Ideker T: Cytoscape: A software environment for integrated models of biomolecular interaction networks. Genome Res. 13:2498–2504. 2003. View Article : Google Scholar : PubMed/NCBI | |
Tang Z, Li C, Kang B, Gao G, Li C and Zhang Z: GEPIA: A web server for cancer and normal gene expression profiling and interactive analyses. Nucleic Acids Res. 45(W1): W98–W102. 2017. View Article : Google Scholar : PubMed/NCBI | |
Uhlén M, Fagerberg L, Hallström BM, Lindskog C, Oksvold P, Mardinoglu A, Sivertsson Å, Kampf C, Sjöstedt E, Asplund A, et al: Proteomics. Tissue-based map of the human proteome. Science. 347:12604192015. View Article : Google Scholar : PubMed/NCBI | |
Gao J, Aksoy BA, Dogrusoz U, Dresdner G, Gross B, Sumer SO, Sun Y, Jacobsen A, Sinha R, Larsson E, et al: Integrative analysis of complex cancer genomics and clinical profiles using the cBioPortal. Sci Signal. 6:pl12013. View Article : Google Scholar : PubMed/NCBI | |
Cerami E, Gao J, Dogrusoz U, Gross BE, Sumer SO, Aksoy BA, Jacobsen A, Byrne CJ, Heuer ML, Larsson E, et al: The cBio cancer genomics portal: An open platform for exploring multidimensional cancer genomics data. Cancer Discov. 2:401–404. 2012. View Article : Google Scholar : PubMed/NCBI | |
Huang da W, Sherman BT and Lempicki RA: Systematic and integrative analysis of large gene lists using DAVID bioinformatics resources. Nat Protoc. 4:44572009. View Article : Google Scholar : PubMed/NCBI | |
Maere S, Heymans K and Kuiper M: BiNGO: A Cytoscape plugin to assess overrepresentation of gene ontology categories in biological networks. Bioinformatics. 21:3448–3449. 2005. View Article : Google Scholar : PubMed/NCBI | |
Montojo J, Zuberi K, Rodriguez H, Kazi F, Wright G, Donaldson SL, Morris Q and Bader GD: GeneMANIA Cytoscape plugin: Fast gene function predictions on the desktop. Bioinformatics. 26:2927–2928. 2010. View Article : Google Scholar : PubMed/NCBI | |
Szklarczyk D, Morris JH, Cook H, Kuhn M, Wyder S, Simonovic M, Santos A, Doncheva NT, Roth A, Bork P, et al: The STRING database in 2017: Quality-controlled protein-protein association networks, made broadly accessible. Nucleic Acids Res. 45:D362–D368. 2017. View Article : Google Scholar : PubMed/NCBI | |
Lu X, Sun W, Tang Y, Zhu L, Li Y, Ou C, Yang C, Su J, Luo C, Hu Y and Cao J: Identification of key genes in hepatocellular carcinoma and validation of the candidate gene, cdc25a, using gene set enrichment analysis, meta-analysis and cross-species comparison. Mol Med Rep. 13:1172–1178. 2016. View Article : Google Scholar : PubMed/NCBI | |
MacDonald JW and Ghosh D: COPA-cancer outlier profile analysis. Bioinformatics. 22:2950–2951. 2006. View Article : Google Scholar : PubMed/NCBI | |
Luo X, Zuo L, Kranzler HR, Wang S, Anton RF and Gelernter J: Recessive genetic mode of an ADH4 variant in substance dependence in African-Americans: A model of utility of the HWD test. Behav Brain Funct. 4:422008. View Article : Google Scholar : PubMed/NCBI | |
Edenberg HJ, Xuei X, Chen HJ, Tian H, Wetherill LF, Dick DM, Almasy L, Bierut L, Bucholz KK, Goate A, et al: Association of alcohol dehydrogenase genes with alcohol dependence: a comprehensive analysis. Hum Mol Genet. 15:1539–1549. 2006. View Article : Google Scholar : PubMed/NCBI | |
Edenberg HJ, Jerome RE and Li M: Polymorphism of the human alcohol dehydrogenase 4 (ADH4) promoter affects gene expression. Pharmacogenetics. 9:25–30. 1999. View Article : Google Scholar : PubMed/NCBI | |
Guindalini C, Scivoletto S, Ferreira RGM, Breen G, Zilberman M, Peluso MA and Zatz M: Association of genetic variants in alcohol dehydrogenase 4 with alcohol dependence in Brazilian patients. Am J Psychiatry. 162:1005–1007. 2005. View Article : Google Scholar : PubMed/NCBI | |
Luo X, Kranzler HR, Zuo L, Wang S and Gelernter J: Personality traits of agreeableness and extraversion are associated with ADH4 variation. Biol Psychiatry. 61:599–608. 2007. View Article : Google Scholar : PubMed/NCBI | |
Goode EL, White KL, Vierkant RA, Phelan CM, Cunningham JM, Schildkraut JM, Berchuck A, Larson MC, Fridley BL, Olson JE, et al: Xenobiotic-metabolizing gene polymorphisms and ovarian cancer risk. Mol Carcinog. 50:397–402. 2011. View Article : Google Scholar : PubMed/NCBI | |
Oze I, Matsuo K, Suzuki T, Kawase T, Watanabe M, Hiraki A, Ito H, Hosono S, Ozawa T, Hatooka S, et al: Impact of multiple alcohol dehydrogenase gene polymorphisms on risk of upper aerodigestive tract cancers in a Japanese population. Cancer Epidemiol Biomarkers Prev. 18:3097–3102. 2009. View Article : Google Scholar : PubMed/NCBI | |
Wei RR, Zhang MY, Rao HL, Pu HY, Zhang HZ and Wang HY: Identification of ADH4 as a novel and potential prognostic marker in hepatocellular carcinoma. Med Oncol. 29:2737–2743. 2012. View Article : Google Scholar : PubMed/NCBI | |
Wang X, Yu T, Liao X, Yang C, Han C, Zhu G, Huang K, Yu L, Qin W, Su H, et al: The prognostic value of CYP2C subfamily genes in hepatocellular carcinoma. Cancer Med. 7:966–980. 2018. View Article : Google Scholar : PubMed/NCBI | |
Gelboin HV and Krausz K: Monoclonal antibodies and multifunctional cytochrome P450: Drug metabolism as paradigm. J Clin Pharmacol. 46:353–372. 2006. View Article : Google Scholar : PubMed/NCBI | |
Goldstein JA and de Morais SM: Biochemistry and molecular biology of the human CYP2C subfamily. Pharmacogenetics. 4:285–299. 1994. View Article : Google Scholar : PubMed/NCBI | |
Hamman MA, Thompson GA and Hall SD: Regioselective and stereoselective metabolism of ibuprofen by human cytochrome P450 2C. Biochem Pharmacol. 54:33–41. 1997. View Article : Google Scholar : PubMed/NCBI | |
Jaakkola T, Laitila J, Neuvonen PJ and Backman JT: Pioglitazone is metabolised by CYP2C8 and CYP3A4 in vitro: Potential for interactions with CYP2C8 inhibitors. Basic Clin Pharmacol Toxicol. 99:44–51. 2006. View Article : Google Scholar : PubMed/NCBI | |
Unger T: Inhibiting angiotensin receptors in the brain: Possible therapeutic implications. Curr Med Res Opin. 19:449–451. 2003. View Article : Google Scholar : PubMed/NCBI | |
Kiang TK, Ping CH, Anari MR, Tong V, Abbott FS and Chang TK: Contribution of CYP2C9, CYP2A6, and CYP2B6 to valproic acid metabolism in hepatic microsomes from individuals with the CYP2C9*1/*1 genotype. Toxicol Sci. 94:261–271. 2006. View Article : Google Scholar : PubMed/NCBI | |
Tzveova R, Naydenova G, Yaneva T, Dimitrov G, Vandeva S, Matrozova Y, Pendicheva-Duhlenska D, Popov I, Beltheva O, Naydenov C, et al: Gender-specific effect of CYP2C8*3 on the risk of essential hypertension in bulgarian patients. Biochem Genet. 53:319–333. 2005. View Article : Google Scholar | |
Bosó V, Herrero MJ, Santaballa A, Palomar L, Megias JE, de la Cueva H, Rojas L, Marqués MR, Poveda JL, Montalar J and Aliño SF: SNPs and taxane toxicity in breast cancer patients. Pharmacogenomics. 15:1845–1858. 2014. View Article : Google Scholar : PubMed/NCBI | |
Liu W, Wang B, Ding HU, Wang DW and Zeng H: A potential therapeutic effect of CYP2C8 overexpression on anti-TNF-α activity. Int J Mol Med. 34:725–732. 2014. View Article : Google Scholar : PubMed/NCBI | |
Wei X, Zhang D, Dou X, Niu N, Huang W, Bai J and Zhang G: Elevated 14,15-epoxyeicosatrienoic acid by increasing of cytochrome P450 2C8, 2C9 and 2J2 and decreasing of soluble epoxide hydrolase associated with aggressiveness of human breast cancer. BMC Cancer. 14:8412014. View Article : Google Scholar : PubMed/NCBI | |
Yu D, Green B, Marrone A, Guo Y, Kadlubar S, Lin D, Fuscoe J, Pogribny I and Ning B: Suppression of CYP2C9 by microRNA hsa-miR-128-3p in human liver cells and association with hepatocellular carcinoma. Sci Rep. 5:85342015. View Article : Google Scholar : PubMed/NCBI | |
Wang J, Greene S, Eriksson LC, Reihnér E, Reihner E, Einarsson C, Eggertsen G and Gåfvels M: Human sterol 12a-hydroxylase (CYP8B1) is mainly expressed in hepatocytes in a homogenous pattern. Histochem Cell Biol. 123:441–446. 2005. View Article : Google Scholar : PubMed/NCBI | |
Björkhem I and Eggertsen G: Genes involved in initial steps of bile acid synthesis. Curr Opin Lipidol. 12:97–103. 2001. View Article : Google Scholar : PubMed/NCBI | |
Xu Y, Li F, Zalzala M, Xu J, Gonzalez FJ, Adorini L, Lee YK, Yin L and Zhang Y: Farnesoid X receptor activation increases reverse cholesterol transport by modulating bile acid composition and cholesterol absorption in mice. Hepatology. 64:1072–1085. 2016. View Article : Google Scholar : PubMed/NCBI | |
Qin J, Han TQ, Yuan WT, Zhang J, Fei J, Jiang ZY, Niu ZM, Zhang KY, Hua Q, Cai XX, et al: Single nucleotide polymorphism rs3732860 in the 3’-untranslated region of CYP8B1 gene is associated with gallstone disease in Han Chinese. J Gastroenterol Hepatol. 28:717–722. 2013. View Article : Google Scholar : PubMed/NCBI | |
Qin J, Jiang ZY, Niu ZM, Zhang KY, Hua Q, Jiang ZH, Wang Y, Huang W, Han TQ and Zhang SD: Association of single nucleotide polymorphism in human CYP8B1 gene with gallstone disease. Zhonghua Yi Xue Za Zhi. 91:2092–2095. 2011.(In Chinese). PubMed/NCBI | |
White DL, Saunders VA, Dang P, Engler J, Venables A, Zrim S, Zannettino A, Lynch K, Manley PW and Hughes T: Most CML patients who have a suboptimal response to imatinib have low OCT-1 activity: Higher doses of imatinib may overcome the negative impact of low OCT-1 activity. Blood. 110:4064–4072. 2007. View Article : Google Scholar : PubMed/NCBI | |
de Lima LT, Vivona D, Bueno CT, Hirata RD, Hirata MH, Luchessi AD, de Castro FA, de Lourdes F, Chauffaille M, Zanichelli MA, et al: Reduced ABCG2 and increased SLC22A1 mRNA expression are associated with imatinib response in chronic myeloid leukemia. Med Oncol. 31:8512014. View Article : Google Scholar : PubMed/NCBI | |
Singh O, Chan JY, Lin K, Heng CC and Chowbay B: SLC22A1- ABCB1 haplotype profiles predict imatinib pharmacokinetics in Asian patients with chronic myeloid leukemia. PLoS One. 7:e517712012. View Article : Google Scholar : PubMed/NCBI | |
Rulcova A, Krausova L, Smutny T, Vrzal R, Dvorak Z, Jover R and Pavek P: Glucocorticoid receptor regulates organic cation transporter 1 (OCT1, SLC22A1) expression via HNF4α upregulation in primary human hepatocytes. Pharmacol Rep. 65:1322–1335. 2013. View Article : Google Scholar : PubMed/NCBI | |
Herraez E, Lozano E, Macias RI, Vaquero J, Bujanda L, Banales JM, Marin JJ and Briz O: Expression of SLC22A1 variants may affect the response of hepatocellular carcinoma and cholangiocarcinoma to sorafenib. Hepatology. 58:1065–1073. 2013. View Article : Google Scholar : PubMed/NCBI | |
Lautem A, Heise M, Gräsel A, Hoppe-Lotichius M, Weiler N, Foltys D, Knapstein J, Schattenberg JM, Schad A, Zimmermann A, et al: Downregulation of organic cation transporter 1 (SLC22A1) is associated with tumor progression and reduced patient survival in human cholangiocellular carcinoma. Int J Oncol. 42:1297–1304. 2013. View Article : Google Scholar : PubMed/NCBI | |
Mehere P, Han Q, Lemkul JA, Vavricka CJ, Robinson H, Bevan DR and Li J: Tyrosine aminotransferase: Biochemical and structural properties and molecular dynamics simulations. Protein Cell. 1:1023–1032. 2010. View Article : Google Scholar : PubMed/NCBI | |
Maydan G, Andresen BS, Madsen PP, Zeigler M, Raas- Rothschild A, Zlotogorski A, Gutman A and Korman SH: TAT gene mutation analysis in three Palestinian kindreds with oculocutaneous tyrosinaemia type II; characterization of a silent exonic transversion that causes complete missplicing by exon 11 skipping. J Inherit Metab Dis. 29:620–626. 2006. View Article : Google Scholar : PubMed/NCBI | |
Bouyacoub Y, Zribi H, Azzouz H, Nasrallah F, Abdelaziz RB, Kacem M, Rekaya B, Messaoud O, Romdhane L, Charfeddine C, et al: Novel and recurrent mutations in the TAT gene in Tunisian families affected with Richner-Hanhart syndrome. Gene. 529:45–49. 2003. View Article : Google Scholar | |
Fu L, Dong SS, Xie YW, Tai LS, Chen L, Kong KL, Man K, Xie D, Li Y, Cheng Y, et al: Down-regulation of tyrosine aminotransferase at a frequently deleted region 16q22 contributes to the pathogenesis of hepatocellular carcinoma. Hepatology. 51:1624–1634. 2010. View Article : Google Scholar : PubMed/NCBI | |
Su W, Wang Y, Jia X, Wu W, Li L, Tian X, Li S, Wang C, Xu H, Cao J, et al: Comparative proteomic study reveals 17β-HSD13 as a pathogenic protein in nonalcoholic fatty liver disease. Proc Natl Acad Sci USA. 111:11437–11442. 2014. View Article : Google Scholar : PubMed/NCBI | |
Fujimoto Y, Itabe H, Sakai J, Makita M, Noda J, Mori M, Higashi Y, Kojima S and Takano T: Identification of major proteins in the lipid droplet-enriched fraction isolated from the human hepatocyte cell line HuH7. Biochim Biophys Acta 1644. 47–59. 2004. | |
Chen J, Zhuo JY, Yang F, Liu ZK, Zhou L, Xie HY, Xu X and Zheng SS: 17-beta-hydroxysteroid dehydrogenase 13 inhibits the progression and recurrence of hepatocellular carcinoma. Hepatobiliary Pancreat Dis Int. 17:220–226. 2018. View Article : Google Scholar : PubMed/NCBI |