Alternative Splicing Factor Heterogeneous Nuclear Ribonucleoprotein U as a Promising Biomarker for Gastric Cancer Risk and Prognosis with Tumor-Promoting Properties.

Gastric cancer (GC) is a major global health concern with poor outcomes. Heterogeneous nuclear ribonucleoprotein U (HNRNPU) is a multifunctional protein that participates in pre-mRNA packaging, alternative splicing regulation, and chromatin remodeling. Its potential role in GC remains unclear. In this study, the expression characteristics of HNRNPU were analyzed by The Cancer Genome Atlas data, Gene Expression Omnibus data, and then further identified by real-time quantitative PCR and immunohistochemistry using tissue specimens. From superficial gastritis, atrophic gastritis, and hyperplasia to GC, the in situ expression of HNRNPU protein gradually increased, and the areas under the curve for diagnosis of GC and its precancerous lesions were 0.911 and 0.847, respectively. A nomogram integrating HNRNPU expression, lymph node metastasis, and other prognostic indicators exhibited an area under the curve of 0.785 for predicting survival risk. Knockdown of HNRNPU significantly inhibited GC cell proliferation, migration, and invasion and promoted apoptosis in vitro. In addition, RNA-sequencing analysis showed that HNRNPU could affect alternative splicing events in GC cells, with functional enrichment analysis revealing that HNRNPU may exert malignant biological function in GC progression through alternative splicing regulation. In summary, the increased expression of HNRNPU was significantly associated with the development of GC, with a good performance in diagnosing and predicting the prognostic risk of GC. Functionally, HNRNPU may play an oncogenic role in GC by regulating alternative splicing.

Deep Learning-Based Stratification of Gastric Cancer Patients from Hematoxylin and Eosin-Stained Whole Slide Images by Predicting Molecular Features for Immunotherapy Response.

Determining the molecular characteristics of cancer patients is crucial for optimal immunotherapy decisions. The aim of this study was to screen immunotherapy beneficiaries by predicting key molecular features from hematoxylin and eosin-stained images based on deep learning models. An independent data set from Asian gastric cancer patients was included for external validation. In addition, a segmentation model (Horizontal-Vertical Network) was used to quantify the cellular composition of tumor stroma. The model performance was evaluated by measuring the area under the curve (AUC). The tumor extraction model achieved an AUC of 0.9386 and 0.9062 in the internal and external test sets, respectively. The stratification model could predict the immunotherapy-sensitive subtypes (AUC range, 0.8685 to 0.9461), the genetic mutations (AUC range, 0.8283 to 0.9225), and the pathway activity (AUC range, 0.7568 to 0.8612) fairly accurately. In external validation, the prediction performance of Epstein-Barr virus and programmed cell death ligand 1 expression status achieved AUCs of 0.7906 and 0.6384, respectively. The segmentation model identified a relatively high proportion of inflammatory cells and connective cells in some immunotherapy-sensitive subtypes. The deep learning-based models potentially may serve as a valuable tool to screen for the beneficiaries of immunotherapy in gastric cancer patients.

ATG4B as a novel biomarker for abdominal aortic aneurysm: integrated evaluation through experimental and bioinformatics analyses.

Autophagy related gene 4B (ATG4B) plays a central role in autophagy machinery, but its clinical relevance to AAA remains unknown. In this study, 205 AAA patients and 205 age- and sex-matched controls were included to detect the serum ATG4B levels. Meanwhile, abdominal aortic specimens from 24 AAA patients and 6 human organ donors were collected to evaluate the mRNA and in situ protein expression of ATG4B. We observed significantly higher ATG4B mRNA and protein expression levels in AAA group compared to those in control group, with a positive correlation between mRNA levels and serum/in situ protein levels (serum, r = 0.518, P = 0.010; in situ, r = 0.453, P = 0.026). Serum ATG4B exhibited the diagnostic potential for AAA (AUC = 0.702, sensitivity = 75.6%) and intraluminal thrombus recognition (AUC = 0.602, sensitivity = 67.9%). Logistic regression revealed a significant association between elevated serum ATG4B and an increased risk of AAA and intraluminal thrombus formation. Deceased patients displayed higher baseline serum ATG4B levels, which could predict postoperative mortality (HR = 1.028, 95%CI = 1.007-1.049, P = 0.009, AUC = 0.612, sensitivity = 84.6%). The bioinformatics analysis suggested that ATG4B may modulate cellular autophagy and influence pathways associated with inflammation, lipid metabolism, or apoptosis, thereby contributing to the occurrence and development of AAA. The drug-gene interaction network identified 13 potential therapeutic drugs targeting ATG4B. In conclusion, ATG4B may serve as a promising biomarker for the diagnosis and prognostic assessment of AAA patients and play a key role in the pathogenesis of AAA.

Understanding the unimodal distributions of cancer occurrence rates: it takes two factors for a cancer to occur.

Data from the SEER reports reveal that the occurrence rate of a cancer type generally follows a unimodal distribution over age, peaking at an age that is cancer-type specific and ranges from 30+ through 70+. Previous studies attribute such bell-shaped distributions to the reduced proliferative potential in senior years but fail to explain why some cancers have their occurrence peak at 30+ or 40+. We present a computational model to offer a new explanation to such distributions. The model uses two factors to explain the observed age-dependent cancer occurrence rates: cancer risk of an organ and the availability level of the growth signals in circulation needed by a cancer type, with the former increasing and the latter decreasing with age. Regression analyses were conducted of known occurrence rates against such factors for triple negative breast cancer, testicular cancer and cervical cancer; and all achieved highly tight fitting results, which were also consistent with clinical, gene-expression and cancer-drug data. These reveal a fundamentally important relationship: while cancer is driven by endogenous stressors, it requires sufficient levels of exogenous growth signals to happen, hence suggesting the realistic possibility for treating cancer via cleaning out the growth signals in circulation needed by a cancer.

Potential diagnostic and prognostic value and regulatory relationship of long noncoding RNA CCAT1 and miR-130a-3p in clear cell renal cell carcinoma.

BACKGROUND: MicroRNAs (miRNAs) and long non-coding RNAs (lncRNAs) could interact with each other to play a vital role in the pathogenesis of cancers. We aimed to examine the expression profile, clinical significance and regulatory relationship of miR-130a-3p and its predicted interactive lncRNA in clear cell renal cell carcinoma (ccRCC). METHODS: Bioinformatics analysis was used to predict lncRNAs binding with miR-130a-3p. qRT-PCR was employed to detect the expression levels of miR-130a-3p and the miRNA-targeted lncRNA, and their clinical values in ccRCC were clarified. The lncRNA sponge potential of miR-130a-3p was assessed through dual-luciferase reporter assay and the biological effects of them were observed. RESULTS: Colon cancer associated transcript 1 (CCAT1) directly interacted with miR-130a-3p and negatively regulated miR-130a-3p expression. CCAT1 was upregulated and miR-130a-3p was downregulated in ccRCC cell line and tissues (all P < 0.05). High CCAT1 and low miR-130a-3p expression was correlated with larger tumor size and advanced TNM stage in ccRCC patients. High CCAT1 level suggested a poor survival prognosis. There was a negative association between CCAT1 and miR-130a-3p expression (r = - 0.373, P = 0.010). MiR-130a-3p mimic and si-CCAT1 inhibited ccRCC cell proliferation and invasion, and induced apoptosis. CONCLUSIONS: CCAT1/miR-130a-3p axis may have potential to serve as a novel diagnostic and prognostic target of ccRCC patients.

Expression and prognostic potential of ribosome 18S RNA m6A methyltransferase METTL5 in gastric cancer.

BACKGROUND: Ribosomal RNA N6-methyltransferase METTL5 was reported to catalyze m6A in 18S rRNA. We aimed to investigate the expression and prognostic features of METTL5 in gastric cancer (GC). METHODS: In this study, 168 GC patients and their corresponding adjacent tissues were collected. Immunohistochemical staining was used to detect the expression of METTL5 protein. Univariate and multivariate Cox analysis were used to dertermine the prognostic role of METTL5 protein in GC, and a nomogram was constructed to evaluate GC patients' prognosis based on METTL5 expression. Data from TCGA and GEO database were also used to validate the prognostic value of METTL5 in GC patients on mRNA level. We further performed GSEA enrichment analysis to explore the possible function and related pathways related to METTL5. RESULTS: METTL5 protein in gastric cancer tissues (GCTs) was significantly decreased compared with adjacent normal tissues (ANTs) and adjacent intestinal metaplasia tissues (AIMTs) (P < 0.001, respectively). Meanwhile, METTL5 expression was negatively correlated with clinicopathologic stage. According to multivariate Cox proportional hazards model analysis, METTL5 protein expression was a good independent predictor of GC prognosis (p < 0.05). Patients with high METTL5 expression had better prognosis. The nomogram constructed based on METTL5 expression could predict the prognosis of GC patients well. GSEA analysis showed that genes of METTL5 low expression group were enriched in some oncogenic signaling pathways such as ERBB, MAPK, JAK-STAT, Wnt, and mTOR, as well as some immune pathways, including Fc-gamma R mediated phagocytosis, Fc-epsilon Ri, chemokine, T cell receptor and B cell receptor signaling pathway. While the high expression group of METTL5 was mainly related to oxidative phosphorylation, nucleotide excision repair and mismatch repair. CONCLUSIONS: METTL5 protein was decreased in GCTs compared with AIMTs and ANTs, and it may be a potential prognostic biomarker in GC.

XPF expression and its relationship with the risk and prognosis of colorectal cancer.

BACKGROUND: XPF (xeroderma pigmentosum complementation group F) is a key factor contributing to DNA damage excision of nucleotide excision repair pathway. The relationship between XPF expression and the risk and prognosis of colorectal cancer (CRC) is unclear. METHODS: In this experiment, a total of 824 cases of colorectal tissue were collected. XPF protein expression was detected by immunohistochemical staining. We conducted a Mann-Whitney U test in order to explore the differential expression of XPF between CRC and non-cancer controls, and the correlation between XPF expression and CRC clinicopathological parameters. Univariate and multivariate Cox regression analyses were conducted to investigate the relationship between XPF expression and CRC prognosis. The Java based software GSEA as well as STRING, David, GO, KEGG were used to explore the function and regulation network of XPF. RESULTS: The results demonstrated that the XPF expression in CRC was significantly up-regulated compared with non-tumor controls (P < 0.001) and adenoma tissue (P < 0.001). XPF protein was increased in the dynamic sequence of anal diseases to adenoma tissue to CRC. Expression of XPF was related to tumor location (P = 0.005) and tumor growth pattern (P = 0.009). The results of prognosis analysis suggested that in patients with stage T1-T2, XPF low expression may be significantly associated with better overall survival (HR = 7.978, 95% CI 1.208-52.673, P = 0.031). XPF and its interacting genes played a vital role in different processes of nucleotide excision repair pathway. XPF expression was related with Ubiquitin like protein specific protease activity. CONCLUSIONS: XPF might be a promising biomarker for CRC risk, and also showed potential as a prognostic predictor in CRC patients.

TLR4 rs1927914 polymorphism contributes to serum TLR4 levels in patients with aortic aneurysm.

Toll-like receptor 4 (TLR4) is a crucial regulator of inflammatory reactions and vascular remodeling. Elevated TLR4 expression has been proved to be correlated with an increased risk of aortic aneurysm (AA). This study aimed to explore the influence of TLR4 gene polymorphisms on TLR4 expression levels and its probable functional significance in AA disease. A total of 294 AA patients and 285 controls were enrolled in the study and serum TLR4 levels were detected by ELISA. All the participants were genotyped for two tag-SNPs in TLR4 (rs1927914 in the promoter region and rs11536889 in the 3'-untranslated region) using the KASP method. Relative luciferase activity was measured by the dual-luciferase reporter assay system. The rs1927914 TC, TC/CC genotypes and C allele showed associations with increased serum TLR4 levels in the total population and AA patients (all P<0.05). Further stratified analysis demonstrated that AA subjects with TC or TC/CC genotype of rs1927914 had significantly higher serum levels of TLR4 than those with TT genotype in male, age>60y, hypertension, diabetes, TAA type and size>5.0 cm subgroups (all P<0.05). In binary logistic analysis, rs1927914 TC genotype and dominant model presented significant associations with high TLR4 levels (OR = 1.579 and 1.431, P = 0.020 and 0.049, respectively) after adjusting age, hypertension and diabetes. However, rs11536889 polymorphism had no significant influence on serum TLR4 levels. Regarding rs1927914, luciferase activity of the C allele construct was significantly increased in comparison with the T allele construct (0.589 ± 0.004 vs. 0.340 ± 0.014, P<0.001). Our results provided evidence that rs1927914 polymorphism contributed to serum TLR4 levels, possibly by influencing promoter activity of TLR4, and could be a novel genetic factor in the formation of AA.

Expression profiles and prognostic roles of m6A writers, erasers and readers in gastric cancer.

Aim: To explore the expression profiles of N6-methyladenosine (m6A) enzymes (writers, erasers and readers) and their associations with gastric cancer (GC) prognosis. Methods: Gene expression was analyzed using the UALCAN and Oncomine web resources. The prognostic roles of these genes in GC were analyzed using data from The Cancer Genome Atlas. Results: Thirteen m6A enzymes were found to be upregulated in GC tissues. The expression of m6A writers METTL3, RBM15 and WTAP was associated with pathological stage. The m6A eraser FTO was related to tumor stage and ALKBH5 expression was related to GC prognosis. The m6A reader YTHDF3 expression was associated with tumor stage. YTHDC2 was associated with survival of GC patients. Conclusion: Abnormal changes of key genes involved in m6A RNA methylation may have an important impact on GC development and prognosis.

Lay abstract RNA N6-methyladenosine (m6A) methylation is modulated by a series of epigenetic modulator enzymes termed 'writers', 'erasers' and 'readers'. We aimed to explore the expression profiles of these m6A enzymes and their associations with gastric cancer (GC) development and prognosis. Gene expression was analyzed using the UALCAN and Oncomine web resources. Clinical data were downloaded from The Cancer Genome Atlas. Gene­gene networks and protein­protein interaction networks were built using the softwares STRING and GeneMANIA. Thirteen m6A enzymes were found to be upregulated in GC tissues. The expression of m6A writers METTL3, RBM15 and WTAP was associated with pathological stage. The m6A eraser FTO was related to tumor stage and ALKBH5 expression was related to GC prognosis. The m6A reader YTHDF3 expression was associated with tumor stage, and YTHDC2 was associated with survival of GC patients. In summary, these results suggest that abnormal changes of key genes involved in regulation and function of m6A RNA methylation may have an important impact on GC development and its clinical prognosis.

The expression patterns and the diagnostic/prognostic roles of PTPN family members in digestive tract cancers.

BACKGROUND: Non-receptor protein tyrosine phosphatases (PTPNs) are a set of enzymes involved in the tyrosyl phosphorylation. The present study intended to clarify the associations between the expression patterns of PTPN family members, and diagnosis as well as the prognosis of digestive tract cancers. METHODS: Oncomine and Ualcan were used to analyze PTPN expressions. Data from The Cancer Genome Atlas (TCGA) were downloaded through UCSC Xena for validation and to explore the relationship of the PTPN expression with diagnosis, clinicopathological parameters and survival of digestive tract cancers. Gene ontology enrichment analysis was conducted using the DAVID database. The gene-gene interaction network was performed by GeneMANIA and the protein-protein interaction (PPI) network was built using STRING portal coupled with Cytoscape. The expression of differentially expressed PTPNs in cancer cell lines were explored using CCLE. Moreover, by histological verification, the expression of four PTPNs in digestive tract cancers were further analyzed. RESULTS: Most PTPN family members were associated with digestive tract cancers according to Oncomine, Ualcan and TCGA data. Several PTPN members were differentially expressed in digestive tract cancers. For esophageal carcinoma (ESCA), PTPN1 and PTPN12 levels were correlated with incidence; PTPN20 was associated with poor prognosis. For stomach adenocarcinoma (STAD), PTPN2 and PTPN12 levels were correlated with incidence; PTPN3, PTPN5, PTPN7, PTPN11, PTPN13, PTPN14, PTPN18 and PTPN23 were correlated with pathological grade; PTPN20 expression was related with both TNM stage and N stage; PTPN22 was associated with T stage and pathological grade; decreased expression of PTPN5 and PTPN13 implied worse overall survival of STAD, while elevated PTPN6 expression indicated better prognosis. For colorectal cancer (CRC), PTPN2, PTPN21 and PTPN22 levels were correlated with incidence; expression of PTPN5, PTPN12, and PTPN14 was correlated with TNM stage and N stage; high PTPN5 or PTPN7 expression was associated with increased hazards of death. CCLE analyses showed that in esophagus cancer cell lines, PTPN1, PTPN4 and PTPN12 were highly expressed; in gastric cancer cell lines, PTPN2 and PTPN12 were highly expressed; in colorectal cancer cell lines, PTPN12 was highly expressed while PTPN22 was downregulated. Results of histological verification experiment showed differential expressions of PTPN22 in CRC, and PTPN12 in GC and CRC. CONCLUSIONS: Members of PTPN family were differentially expressed in digestive tract cancers. Correlations were found between PTPN genes and clinicopathological parameters of patients. Expression of PTPN12 was upregulated in both STAD and CRC, and thus could be used as a diagnostic biomarker. Differential expression of PTPN12 in GC and CRC, and PTPN22 in CRC were presented in our histological verification experiment.

Aberrantly methylated-differentially expressed genes and pathways in Epstein-Barr virus-associated gastric cancer.

Aim: To identify the methylated-differentially expressed genes (MDEGs) that may serve as diagnostic markers and therapeutic targets in Epstein-Barr virus-associated gastric cancer (EBVaGC) and to explore the methylation-based pathways for elucidating biological mechanisms of EBVaGC. Materials & methods: Gene expression and methylation profiles were downloaded from GEO database. MDEGs were identified by GEO2R. Pathway enrichment analyses were conducted based on DAVID database. Hub genes were identified by Cytoscape, which were further verified by The Cancer Genome Atlas database. Results: A total of 367 hypermethylated, lowly expressed genes were enriched in specific patterns of cell differentiation. 31 hypomethylated, highly expressed genes demonstrated enrichment in regulation of immune system process. After validation using The Cancer Genome Atlas database, seven genes were confirmed to be significantly different hub genes in EBVaGC. Conclusion: EBVaGC-specific MDEGs and pathways can be served as potential biomarkers for precise diagnosis and treatment of EBVaGC and provide novel insights into the mechanisms involved.

Key elements involved in Epstein-Barr virus-associated gastric cancer and their network regulation.

BACKGROUND: The molecular mechanism of Epstein-Barr virus (EBV)-associated gastric cancer (EBVaGC) remains elusive. A collection of molecular regulators including transcription factor and noncoding RNA (ncRNAs) may affect the carcinogenesis of EBVaGC by regulating the expression and function of key genes. In this study, integration of multi-level expression data and bioinformatics approach was used to identify key elements and their interactions involved in mechanism of EBVaGC and their network regulation. METHODS: Data of the gene expression profiling data sets (GSE51575) was downloaded from GEO database. Differentially expressed genes between EBVaGC and normal samples were identified by GEO2R. Gene ontology and pathway enrichment analyses were performed using R packages Cluster profiler. STRING database was used to find interacting proteins between different genes. Transcription factors in differentially expressed genes were obtained from TF Checkpoint database. Using Cytoscape, we built transcription factor regulation network. miRNAs involved in the gene-interacting proteins and the miRNA-targeted lncRNA were predicted through miRWalk. Using ViRBase, EBV related miRNA regulation network was built. Overlapping genes and regulators of the above three networks were further identified, and the cross network was constructed using Cytoscape software. Moreover, the differential expressions of the target genes and transcription factors in the cross network were explored in different molecular subtypes of GC using cBioPortal. By histological verification, the expression of two main target genes in the cross network were further analyzed. RESULTS: A total of 104 genes showed differential expressions between EBVaGC and normal tissues, which were associated with digestion, G-protein coupled receptor binding, gastric acid secretion, etc. Pathway analysis showed that the differentially expressed genes were mainly enriched in gastric acid secretion and protein digestion and absorption. Using STRING dataset, a total of 54 proteins interacted with each other. Based on the transcription factor network, the hub transcription factors IRX3, NKX6-2, PTGER3 and SMAD5 were identified to regulate their target genes SST and GDF5, etc. After screening and matching in miRwalk datasets, a ceRNA network was established, in which the top five miRNAs were hsa-miR-4446-3p, hsa-miR-5787, hsa-miR-1915-3p, hsa-miR-335-3p and hsa-miR-6877-3p, and the top two lncRNAs were RP5-1039K5.19 and TP73-AS1. According to the EBV related miRNA regulation network, CXCL10 and SMAD5 were found to be regulated by EBV-miR-BART1-3p and EBV-mir-BART22, respectively. By overlapping the three networks, CXCL10, GDF5, PTGER3, SMAD5, miR-6877-3p, RP5-1039K5.19, TP73-AS1, EBV-miR-BART1-3p and EBV-mir-BART22 were found to be key elements of regulation mechanism of EBVaGC. CXCL10, GDF5, PTGER3 and SMAD5 were also differentially expressed among the four molecular subtypes of GC. The histological verification experiment showed differential expressions of the two main target genes GDF5 and CXCL10 between EBVaGC and non-tumor tissues as well as EBVnGC. CONCLUSION: In the current study, our results revealed key elements and their interactions involved in EBVaGC. Some hub transcription factors, miRNAs, lncRNAs and EBV related miRNAs were observed to regulate their target genes. Overlapping genes and regulators were observed in diverse regulation networks, such as CXCL10, GDF5, PTGER3, SMAD5, miR-6877-3p, RP5-1039K5.19, TP73-AS1, EBV-miR-BART1-3p and EBV-mir-BART22. Moreover, CXCL10, GDF5, PTGER3 and SMAD5 were also differentially expressed among the four molecular subtypes of GC. The histological verification experiment showed differential expressions of the two main target genes GDF5 and CXCL10 between EBVaGC and non-tumor tissues as well as EBVnGC. Therefore, the identified key elements and their network regulation may be specifically involved in EBVaGC mechanisms.

Serum matrix metalloproteinase-9 is a valuable biomarker for identification of abdominal and thoracic aortic aneurysm: a case-control study.

BACKGROUND: Matrix metalloproteinase-9 (MMP9) has been reported to play a key role in the pathogenesis of aortic aneurysm. However, few studies have assessed serum MMP9 levels in both abdominal aortic aneurysm (AAA) and thoracic aortic aneurysm (TAA). In this study, we investigated the serum levels of MMP9 in aortic aneurysm to evaluate its predictive and diagnostic efficacy for AAA and TAA, and explored the association of MMP9 with circulating laboratory markers. METHODS: A total of 296 subjects were enrolled, including 105 AAA patients, 79 TAA patients and 112 healthy controls. The levels of serum MMP9 were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS: Compared to control group, both AAA and TAA patients had higher serum MMP9 levels in the overall comparison and subgroup analysis based on subjects aged<65 years, either male or female, hypertension, non-diabetes and non-hyperlipidemia (all P<0.05). Moreover, MMP9 levels were significantly higher in TAA group than those in AAA group in the total comparison, and this discrepancy was also found in the non-diabetes, non-hyperlipidemia and aortic diameter ≥ 5.5 cm subgroup analysis. Serum MMP9 levels were influenced by age and hypertension. There was a positive association of serum MMP9 with CRP (r = 0.33, P < 0.001) and Hcy (r = 0.199, P = 0.033). Multiple logistic analyses showed that serum MMP9 was an independent risk factor for AAA and TAA. Based on receiver operating characteristic (ROC) analysis, the area under the curve (AUC) of MMP9 for predicting TAA was 0.83 with 70% sensitivity and 91% specificity, while the AUC of MMP9 to detect AAA was 0.69 and the sensitivity and specificity were 50% and 88%. CONCLUSIONS: Serum MMP9 was closely related to the existence of aortic aneurysms and could be a valuable marker for the discrimination of aortic aneurysm, especially for TAA.

Serum levels of matrix metalloproteinase 9 and toll-like receptor 4 in acute aortic dissection: a case-control study.

BACKGROUND: Matrix metalloproteinase 9 (MMP9) and Toll-like receptor 4 (TLR4) play important roles in aortic pathophysiology. However, there is lacking research on serum TLR4 levels in acute aortic dissection (AAD) patients, and the performance of serum MMP9 and TLR4 for the diagnosis of AAD is still unknown. This study aimed to evaluate the serum levels of MMP9 and TLR4 in AAD patients, identify their associations with circulating C-reactive protein (CRP) and D-dimer, which are well-known classical biomarkers of AAD, and further explore the potential diagnostic role of MMP9 and TLR4 in AAD. METHODS: Serum levels of MMP9 and TLR4 were measured by enzyme-linked immunosorbent assay (ELISA) in 88 AAD patients and 88 controls. The clinical test related information was collected from patients' electronic medical records. RESULTS: Serum MMP9 and TLR4 levels were significantly higher in AAD patients than those in healthy controls in the general and stratified comparisons. Either serum MMP9 or TLR4 was independently associated with the risk of AAD (all p < 0.001). There was a positive significant association between serum MMP9 and TLR4 (r = 0.518, p < 0.001). Both MMP9 and TLR4 levels were statistically correlated with circulating CRP, but not D-dimer. Based on receiver-operating characteristic (ROC) analysis, the area under the curves (AUCs) of MMP9 and TLR4 alone for the diagnosis of AAD were 0.810 and 0.799 with optimal cut-off points of 379.47 ng/ml and 7.83 ng/ml, respectively. Moreover, a combination of serum MMP9 and TLR4 increased the AUC to 0.89 with a sensitivity of 60.2% and specificity of 94.3%. CONCLUSIONS: Serum MMP9 and TLR4 could be potential biomarkers for identifying AAD, while the combined diagnostic value was higher in safely ruling out AAD.

Expression of DDB2 Protein in the Initiation, Progression, and Prognosis of Colorectal Cancer.

BACKGROUND: Damage-specific DNA binding protein 2 (DDB2) is implicated in the recognition of DNA damage and the initiation of nucleotide excision repair process. The aim of this study was to explore the role of DDB2 in the initiation, progression, and prognosis of colorectal cancer (CRC). METHODS: Totally tissues of 300 CRC and 300 adjacent, 267 colorectal adenoma (CRA) and 214 normal (NOR) were collected. The expression of DDB2 protein was detected by immunohistochemical staining. RESULTS: DDB2 protein was highly expressed in CRC and CRA compared with NOR (P < 0.001, respectively) in the dynamic sequence of NOR → CRA → CRC; CRC tissue demonstrated increased DDB2 expression compared with non-tumor adjacent tissues (P < 0.001). DDB2 expression was higher in T1-T2 than that in T3-T4 in CRC (P = 0.023); cloddy/nested CRC demonstrated increased DDB2 expression than infiltrative CRC (P = 0.007). Survival analysis showed that high DDB2 expression was associated with favorable survival in colon cancer (adjusted HR 0.20, 95% CI 0.06-0.72, P = 0.014) and female CRC patients (adjusted HR 0.27, 95% CI 0.08-0.92, P = 0.036). CONCLUSION: DDB2 protein expression was associated with the initiation, progression, and prognosis of CRC, and might function as a tumor biomarker for the diagnosis and prognosis of CRC.

A Serological Biopsy Using Five Stomach-Specific Circulating Biomarkers for Gastric Cancer Risk Assessment: A Multi-Phase Study.

OBJECTIVES: We aimed to assess a serological biopsy using five stomach-specific circulating biomarkers-pepsinogen I (PGI), PGII, PGI/II ratio, anti-Helicobacter pylori (H. pylori) antibody, and gastrin-17 (G-17)-for identifying high-risk individuals and predicting risk of developing gastric cancer (GC). METHODS: Among 12,112 participants with prospective follow-up from an ongoing population-based screening program using both serology and gastroscopy in China, we conducted a multi-phase study involving a cross-sectional analysis, a follow-up analysis, and an integrative risk prediction modeling analysis. RESULTS: In the cross-sectional analysis, the five biomarkers (especially PGII, the PGI/II ratio, and H. pylori sero-positivity) were associated with the presence of precancerous gastric lesions or GC at enrollment. In the follow-up analysis, low PGI levels and PGI/II ratios were associated with higher risk of developing GC, and both low (<0.5 pmol/l) and high (>4.7 pmol/l) G-17 levels were associated with higher risk of developing GC, suggesting a J-shaped association. In the risk prediction modeling analysis, the five biomarkers combined yielded a C statistic of 0.803 (95% confidence interval (CI)=0.789-0.816) and improved prediction beyond traditional risk factors (C statistic from 0.580 to 0.811, P<0.001) for identifying precancerous lesions at enrollment, and higher serological biopsy scores based on the five biomarkers at enrollment were associated with higher risk of developing GC during follow-up (P for trend <0.001). CONCLUSIONS: A serological biopsy composed of the five stomach-specific circulating biomarkers could be used to identify high-risk individuals for further diagnostic gastroscopy, and to stratify individuals' risk of developing GC and thus to guide targeted screening and precision prevention.

Temporal changes in serum biomarkers and risk for progression of gastric precancerous lesions: a longitudinal study.

Effectively managing precancerous lesions is crucial to reducing the gastric cancer (GC) burden. We evaluated associations of temporal changes in multiple serological markers (pepsinogen I [PGI], PGII, PGI/II ratio, gastrin-17 and anti-Helicobacter pylori IgG) with risk for progression of gastric precancerous lesions. From 1997 to 2011, repeated esophagogastroduodenoscopies with gastric mucosal biopsies and blood sample collections were conducted on 2,039 participants (5,070 person-visits) in the Zhuanghe Gastric Diseases Screening Program, Liaoning, China. Serum biomarkers were measured using ELISA, and gastric biopsies were evaluated using standardized histologic criteria. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using generalized estimating equations for correlated binary outcomes. The ORs for progression of gastric conditions comparing those whose serum PGI, PGII, and anti-H. pylori IgG levels increased ≥ 50% relative to those whose decreased ≥ 50% were, respectively 1.67 (CI, 1.22-2.28), 1.80 (CI, 1.40-2.33) and 1.93 (CI, 1.48-2.52). The OR for those whose PGI/II ratio decreased ≥ 50% relative to those whose increased ≥ 50% was 1.40 (CI, 1.08-1.81), and for those whose PGII and anti-H. pylori IgG levels both increased ≥ 50% relative to those whose levels both decreased ≥ 50% the OR was 3.18 (CI, 2.05-4.93). Changes in gastrin-17 were not statistically significantly associated with progression. These findings suggest that temporal changes in serum PGI, PGII, PGI/II ratio, and anti-H. pylori IgG levels (especially PGII and anti-H. pylori IgG combined) may be useful for assessing and managing risk for progression of gastric precancerous lesions.

Effect of ERCC8 tagSNPs and their association with H. pylori infection, smoking, and alcohol consumption on gastric cancer and atrophic gastritis risk.

Excision repair cross-complementing group 8 (ERCC8) plays a critical role in DNA repair. Genetic polymorphisms in ERCC8 may contribute to the risk of cancer development. We selected tag single nucleotide polymorphisms (tagSNPs) in Chinese patients from the HapMap database to investigate associations with gastric cancer and its precursors. Genomic DNA was extracted from 394 controls, 394 atrophic gastritis, and 394 gastric cancer cases in northern Chinese patients, and genotypes were identified using the Sequenom MassARRAY system. We found that the ERCC8 rs158572 GG+GA genotype showed a 1.651-fold (95 % confidence interval (CI) = 1.109-2.457, P = 0.013) increased risk of gastric cancer compared with the AA genotype, especially in diffuse type. Stratified analysis comparing the common genotype revealed significantly increased gastric cancer risk in males and individuals older than 50 years with rs158572 GA/GG/GG+GA genotypes, while individuals older than 50 years with rs158916 CT/CC+CT genotypes were less susceptible to atrophic gastritis. Haplotype analysis showed that the G-T haplotype was associated with increased risk of gastric cancer. Statistically significant interactions between the two ERCC8 tagSNPs and Helicobacter pylori infection were observed for gastric cancer and atrophic gastritis risk (P < 0.05). Smokers and drinkers with ERCC8 rs158572 GG+GA genotype were more susceptible to gastric cancer compared with non-smokers and non-drinkers homozygous for AA. Our findings suggested that ERCC8 rs158572 and rs158916, alone or together with environmental factors, might be associated with gastric cancer and atrophic gastritis susceptibility. Further validation of our results in larger populations along with additional studies evaluating the underlying molecular function is required.

A comprehensive evaluation of fasting serum gastrin-17 as a predictor of diseased stomach in Chinese population.

BACKGROUND AND AIM: Fasting serum gastrin-17 (FsG17) is considered as a noninvasive biomarker reflecting the structure and functional status of gastric mucosa, but its clinical utility remains unclear. This study aimed to evaluate FsG17 comprehensively: establish the ranges and cut-off points of FsG17 levels in different gastric diseases, identify their influencing factors, and investigate the accuracy of FsG17 for identifying diseased stomach. METHODS: The study included 4064 participants from Northern China between 2008 and 2013. FsG17 and serum Helicobacter pylori IgG antibody levels were measured by enzyme-linked immunosorbent assay. Diagnostic accuracy was assessed by receiver operator characteristic curves. Multivariate logistic regression analysis was performed to determine the best predictors of gastric histopathological conditions. RESULTS: Median FsG17 levels in healthy, non-atrophic, atrophic, and cancerous stomachs were 1.8, 4.0, 3.8, and 6.1 pmol/l, respectively. Age, smoking status, alcohol consumption, H. pylori infection, and predominant lesion site were factors that affected FsG17 levels. The optimal cut-off values for FsG17 were 3.0 pmol/l (sensitivity of 59.3% and specificity of 67.3%) for discriminating between healthy stomach and diseased stomach and 10.7 pmol/l (sensitivity of 37% and specificity of 83.7%) for discriminating between cancerous stomach and cancer-free stomach; the screening accuracy was higher (sensitivity of 50.0% and specificity of 83.0%) for gastric cancer in the corpus. Multivariate analysis showed that FsG17, gender, age, and H. pylori infection were independent predictors of cancerous stomach. CONCLUSION: With the progression from health stomach to malignancy, FsG17 levels significantly increased and were influenced by other factors. FsG17 combined with age, gender, and H. pylori infection could distinguish between cancerous stomach and cancer-free stomach. The results will enhance our understanding of the potential clinical utility of FsG17.

Serum anti-Helicobacter pylori immunoglobulin G titer correlates with grade of histological gastritis, mucosal bacterial density, and levels of serum biomarkers.

OBJECTIVE. Clinical implications of serum anti-Helicobacter pylori immunoglobulin G (IgG) titer were unclear. This study investigated the associations of serum anti-H. pylori IgG titer with grade of histological gastritis, mucosal bacterial density and levels of serum biomarkers, including pepsinogen (PG) I, PGII, PGI/II ratio and gastrin-17. MATERIAL AND METHODS. Study participants were from a screening program in northern China. Serum anti-H. pylori IgG measurements were available for 5922 patients with superficial gastritis. Serum anti-H. pylori IgG titer and serum biomarkers were measured using ELISA, and gastric biopsies were evaluated using standardized criteria. RESULTS. In patients with mild, moderate or severe superficial gastritis, the mean serum anti-H. pylori IgG titers were 17.3, 33.4 and 54.4 EIU (p for trend < 0.0001), respectively. As mucosal H. pylori density score increased from 0 to 3, the mean serum anti-H. pylori IgG titers also increased from 24.7 to 44.8 EIU (p for trend < 0.0001). Serum anti-H. pylori IgG titer was associated positively with serum PGI, PGII and gastrin-17 concentrations and negatively with PGI/II ratio, and the association was the strongest for PGII. The mean PGII concentration of the patients in the highest quartile of IgG titer was twice the mean concentration of the patients in the lowest quartile (17.2 vs. 8.6 EIU, p < 0.0001). CONCLUSIONS. Our results suggest that serum anti-H. pylori IgG titer was associated positively with grade of histological gastritis, mucosal bacterial density and concentrations of serum PGI, PGII and gastrin-17, and negatively with PGI/II ratio.