m 6 A-mediated gluconeogenic enzyme PCK1 upregulation protects against hepatic ischemia-reperfusion injury.

BACKGROUND AND AIMS: Ischemia-reperfusion (I/R) injury frequently occurs during liver surgery, representing a major reason for liver failure and graft dysfunction after operation. The metabolic shift from oxidative phosphorylation to glycolysis during ischemia increased glucose consumption and accelerated lactate production. We speculate that donor livers will initiate gluconeogenesis, the reverse process of glycolysis in theory, to convert noncarbohydrate carbon substrates (including lactate) to glucose to reduce the loss of hepatocellular energy and foster glycogen storage for use in the early postoperative period, thus improving post-transplant graft function. APPROACH AND RESULTS: By analyzing human liver specimens before and after hepatic I/R injury, we found that the rate-limiting enzyme of gluconeogenesis, PCK1, was significantly induced during liver I/R injury. Mouse models with liver I/R operation and hepatocytes treated with hypoxia/reoxygenation confirmed upregulation of PCK1 during I/R stimulation. Notably, high PCK1 level in human post-I/R liver specimens was closely correlated with better outcomes of liver transplantation. However, blocking gluconeogenesis with PCK1 inhibitor aggravated hepatic I/R injury by decreasing glucose level and deepening lactate accumulation, while overexpressing PCK1 did the opposite. Further mechanistic study showed that methyltransferase 3-mediated RNA N6-methyladinosine modification contributes to PCK1 upregulation during hepatic I/R injury, and hepatic-specific knockout of methyltransferase 3 deteriorates liver I/R injury through reducing the N6-methyladinosine deposition on PCK1 transcript and decreasing PCK1 mRNA export and expression level. CONCLUSIONS: Our study found that activation of the methyltransferase 3/N6-methyladinosine-PCK1-gluconeogenesis axis is required to protect against hepatic I/R injury, providing potential intervention approaches for alleviating hepatic I/R injury during liver surgery.

The non-invasive serum biomarkers contributes to indicate liver fibrosis staging and evaluate the progress of chronic hepatitis B.

BACKGROUND: This study aimed to evaluate the diagnostic abilities of the non-invasive serum biomarkers to predict liver fibrosis staging and evaluate the progress of hepatitis B. METHODS: We enrolled 433 patients with chronic HBV infection had complete medical data available for the study, who underwent percutaneous liver biopsy. The extent of fibrosis was assessed using the modified METAVIR score. The predictive values of the non-invasive serum biomarkers were evaluated by the areas under the receiving operator characteristics curves (AUROCs) with 95% confidence intervals. RESULTS: The proportion of males with progressive stages of liver fibrosis was relatively larger, and the average age of patients with cirrhosis stages is older than the non-cirrhotic stages. We found PLT, GGT, ALP, TB, FIB4 and GPR to be significantly associated with liver fibrosis in our cohort. GGT showed a sensitivity of 71.4% and specificity of 76.7% in distinguishing cirrhosis (F4) from non-cirrhotic stages (F1-3), with an AUROC of 0.775 (95%CI 0.711-0.840).The AUROCs of the GPR in distinguishing cirrhosis (F4) from non-cirrhotic stages (F1-3) was 0.794 (95%CI 0.734-0.853), but it had a lower sensitivity of 59.2%. Additionally, GGT, FIB4, and GPR could differentiate advanced fibrosis (F3-4) from non-advanced fibrosis (F1-2) among individuals with chronic hepatitis B, with AUROCs of 0.723 (95%CI 0.668-0.777), 0.729 (95%CI 0.675-0.782), and 0.760 (95%CI: 0.709-0.811) respectively. CONCLUSIONS: GGT was a better biomarker to distinguish cirrhosis (F4) from non-cirrhotic stages (F1-3), while GPR was a better biomarker to identify advanced fibrosis (F3-4) and non-advanced fibrosis (F1-2) in patients with chronic hepatitis B.

Deep Learning-Based Classification of Hepatocellular Nodular Lesions on Whole-Slide Histopathologic Images.

BACKGROUND & AIMS: Hepatocellular nodular lesions (HNLs) constitute a heterogeneous group of disorders. Differential diagnosis among these lesions, especially high-grade dysplastic nodules (HGDNs) and well-differentiated hepatocellular carcinoma (WD-HCC), can be challenging, let alone biopsy specimens. We aimed to develop a deep learning system to solve these puzzles, improving the histopathologic diagnosis of HNLs (WD-HCC, HGDN, low-grade DN, focal nodular hyperplasia, hepatocellular adenoma), and background tissues (nodular cirrhosis, normal liver tissue). METHODS: The samples consisting of surgical and biopsy specimens were collected from 6 hospitals. Each specimen was reviewed by 2 to 3 subspecialists. Four deep neural networks (ResNet50, InceptionV3, Xception, and the Ensemble) were used. Their performances were evaluated by confusion matrix, receiver operating characteristic curve, classification map, and heat map. The predictive efficiency of the optimal model was further verified by comparing with that of 9 pathologists. RESULTS: We obtained 213,280 patches from 1115 whole-slide images of 738 patients. An optimal model was finally chosen based on F1 score and area under the curve value, named hepatocellular-nodular artificial intelligence model (HnAIM), with the overall 7-category area under the curve of 0.935 in the independent external validation cohort. For biopsy specimens, the agreement rate with subspecialists' majority opinion was higher for HnAIM than 9 pathologists on both patch level and whole-slide images level. CONCLUSIONS: We first developed a deep learning diagnostic model for HNLs, which performed well and contributed to enhancing the diagnosis rate of early HCC and risk stratification of patients with HNLs. Furthermore, HnAIM had significant advantages in patch-level recognition, with important diagnostic implications for fragmentary or scarce biopsy specimens.

The m6A methyltransferase Mettl3 deficiency attenuates hepatic stellate cell activation and liver fibrosis.

Activation of hepatic stellate cells (HSCs) is a central driver of liver fibrosis. Previous investigations have identified various altered epigenetic landscapes during the cellular progression of HSC activation. N6-methyladenosine (m6A) is the most abundant internal RNA modification in eukaryotic cells and is dynamically regulated under various physiological and pathophysiological conditions. However, the functional role of Mettl3-mediated m6A in liver fibrosis remains elusive. Here, we found that the HSC-specific knockout of m6A methyltransferase Mettl3 suppressed HSC activation and significantly alleviated liver fibrosis. Multi-omics analysis of HSCs showed that Mettl3 depletion reduced m6A deposition on mRNA transcripts of Lats2 (a central player of the Hippo/YAP signaling pathway) and slowed down their degradation. Elevated Lats2 increased phosphorylation of the downstream transcription factor YAP, suppressed YAP nuclear translocation, and decreased pro-fibrotic gene expression. Overexpressing YAP mutant resistant to phosphorylation by Lats2 partially rescued the activation and pro-fibrotic gene expression of Mettl3-deficient HSCs. Our study revealed that disruption of Mettl3 in HSCs mitigated liver fibrosis by controlling the Hippo/YAP signaling pathway, providing potential therapeutic strategies to alleviate liver fibrosis by targeting epitranscriptomic machinery.

Spine surgeon specialty differences in single-level percutaneous kyphoplasty.

BACKGROUND: Percutaneous kyphoplasty (PKP) is a procedure performed by a spine surgeon who undergoes either orthopedic or neurosurgical training. The relationship between short-term adverse outcomes and spine specialty is presently unknown. To compare short-term adverse outcomes of single-level PKP when performed by neurosurgeons and orthopedic surgeons in order to develop more concretely preventive strategies for patients under consideration for single-level PKP. METHODS: We evaluated patients who underwent single-level PKP from 2012 to 2014 through the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP). We used univariate analysis and multivariate logistic regression to assess the association between spine surgeon specialty and short-term adverse events, including postoperative complication and unplanned readmission, and to identify different independent risk predictors between two specialties. RESULTS: Of 2248 patients who underwent single-level PKP procedure, 1229 patients (54.7%) had their operations completed by a neurosurgeon. There were no significant differences in the development of the majority of postoperative complications and the occurrence of unplanned readmission between the neurosurgical cohort (NC) and the orthopedic cohort (OC). A difference in the postoperative blood transfusion rate (0.7% NS vs. 1.7% OC, P = 0.039) was noted and may due to the differences in comorbidities between patients. Multivariate regression analysis revealed different independent predictors of postoperative adverse events for the two spine specialties. CONCLUSIONS: By comparing a large range of demographic feature, preoperative comorbidities, and intraoperative factors, we find that short-term adverse events in single-level PKP patients does not affect by spine surgeon specialty, except that the OC had higher postoperative blood transfusion rate. In addition, the different perioperative predictors of postoperative complications and unplanned readmissions were identified between the two specialties. These findings can lead to better evidence-based patient counseling and provide valuable information for medical evaluation and potentially devise methods to reduce patients' risk.

Mitochondrial Dysfunction by FADDosome Promotes Gastric Mucosal Injury in Portal Hypertensive Gastropathy.

Mucosal epithelial death is an essential pathological characteristic of portal hypertensive gastropathy (PHG). FADDosome can regulate mucosal homeostasis by controlling mitochondrial status and cell death. However, it remains ill-defined whether and how the FADDosome is involved in the epithelial death of PHG. The FADDosome formation, mitochondrial dysfunction, glycolysis process and NLRP3 inflammasome activation in PHG from both human sections and mouse models were investigated. NLRP3 wild-type (NLRP3-WT) and NLRP3 knockout (NLRP3-KO) littermate models, critical element inhibitors and cell experiments were utilized. The mechanism underlying FADDosome-regulated mitochondrial dysfunction and epithelial death in PHG was explored. Here, we found that FADD recruited caspase-8 and receptor-interacting serine/threonine-protein kinase 1 (RIPK1) to form the FADDosome to promote Drp1-dependent mitochondrial fission and dysfunction in PHG. Also, FADDosome modulated NOX2 signaling to strengthen Drp1-dependent mitochondrial fission and alter glycolysis as well as enhance mitochondrial reactive oxygen species (mtROS) production. Moreover, due to the dysfunction of electron transport chain (ETC) and alteration of antioxidant enzymes activity, this altered glycolysis also contributed to mtROS production. Subsequently, the enhanced mtROS production induced NLRP3 inflammasome activation to result in the epithelial pyroptosis and mucosal injury in PHG. Thus, the FADDosome-regulated pathways may provide a potential therapeutic target for PHG.

Mitochondrial dysfunction induced by HIF-1α under hypoxia contributes to the development of gastric mucosal lesions.

INTRODUCTION: Hypoxia is an important characteristic of gastric mucosal diseases, and hypoxia-inducible factor-1α (HIF-1α) contributes to microenvironment disturbance and metabolic spectrum abnormalities. However, the underlying mechanism of HIF-1α and its association with mitochondrial dysfunction in gastric mucosal lesions under hypoxia have not been fully clarified. OBJECTIVES: To evaluate the effects of hypoxia-induced HIF-1α on the development of gastric mucosal lesions. METHODS: Portal hypertensive gastropathy (PHG) and gastric cancer (GC) were selected as representative diseases of benign and malignant gastric lesions, respectively. Gastric tissues from patients diagnosed with the above diseases were collected. Portal hypertension (PHT)-induced mouse models in METTL3 mutant or NLRP3-deficient littermates were established, and nude mouse gastric graft tumour models with relevant inhibitors were generated. The mechanisms underlying hypoxic condition, mitochondrial dysfunction and metabolic alterations in gastric mucosal lesions were further analysed. RESULTS: HIF-1α, which can mediate mitochondrial dysfunction via upregulation of METTL3/IGF2BP3-dependent dynamin-related protein 1 (Drp1) N6-methyladenosine modification to increase mitochondrial reactive oxygen species (mtROS) production, was elevated under hypoxic conditions in human and mouse portal hypertensive gastric mucosa and GC tissues. While blocking HIF-1α with PX-478, inhibiting Drp1-dependent mitochondrial fission via mitochondrial division inhibitor 1 (Mdivi-1) treatment or METTL3 mutation alleviated this process. Furthermore, HIF-1α influenced energy metabolism by enhancing glycolysis via lactate dehydrogenase A. In addition, HIF-1α-induced Drp1-dependent mitochondrial fission also enhanced glycolysis. Drp1-dependent mitochondrial fission and enhanced glycolysis were associated with alterations in antioxidant enzyme activity and dysfunction of the mitochondrial electron transport chain, resulting in massive mtROS production, which was needed for activation of NLRP3 inflammasome to aggravate the development of the PHG and GC. CONCLUSIONS: Under hypoxic conditions, HIF-1α enhances mitochondrial dysfunction via Drp1-dependent mitochondrial fission and influences the metabolic profile by altering glycolysis to increase mtROS production, which can trigger NLRP3 inflammasome activation and mucosal microenvironment alterations to contribute to the development of benign and malignant gastric mucosal lesions.

Fine-needle Aspiration Washout Precipitation Specimens: An Acceptable Supplement to Genetic Mutation Detection of Thyroid Nodules.

Objectives: Thyroid nodules are common in adults, but only some of them are malignant. Ultrasound-guided fine-needle aspiration (FNA) is widely applied as a reliable and minimally invasive technique for evaluating thyroid nodules. However, the scarcity of FNA biopsy specimens poses a challenge to molecular diagnosis. This study aimed to evaluate the feasibility of FNA washout precipitation specimens as an effective supplement to the thyroid genetic test. Methods: A total of 115 patients with thyroid nodules were enrolled in our study. The BRAF V600E mutation status was detected in all FNA washout precipitation specimens and biopsy formalin-fixed paraffin-embedded (FFPE) specimens using an amplification refractory mutation system PCR (ARMS-PCR). All patients underwent cytological diagnoses; 79 patients also underwent surgery for histopathological analysis. Results: All the 115 samples were successfully analyzed using both FNA washout precipitation and biopsy FFPE specimens. The results showed that the BRAF V600E status detected in 96 FNA washout precipitation specimens were consistent with that in FNA biopsy FFPE specimens, including 41 BRAF V600E positive and 55 BRAF V600E negative, achieving a concordance rate of 84.4% (kappa = 0.689). Furthermore, the BRAF V600E mutation status using FNA washout precipitation specimens provided a 100.0% positive predictive value for diagnosing papillary thyroid carcinoma in patients with The Bethesda system for reporting thyroid cytopathology (TBSRTC) V. Besides, the BRAF V600E mutation status was positive in 90.9% (10/11) FNA washout precipitation specimens from patients with capsule invasion, achieving a higher overall sensitivity of 100.0%, compared with 57.1% of FNA washout precipitation specimens from patients without capsule invasion. Conclusion: These results suggested that FNA washout precipitation specimens might be a valuable supplementary sample type for detecting the BRAF V600E mutation in patients with thyroid nodules, especially with thyroid capsule invasion.

Prognostic Value of Tumor-Infiltrating Lymphocytes and Tertiary Lymphoid Structures in Epstein-Barr Virus-Associated and -Negative Gastric Carcinoma.

Background: Tumor-infiltrating lymphocytes (TILs) are considered a manifestation of the host immune response against cancer and tertiary lymphoid structures (TLS) may contribute to lymphocytes recruitment. Both of them have been reported as potential prognostic parameters in some human malignancies. However, the roles of TILs, TLS, and their correlation in Epstein-Barr Virus-associated gastric carcinoma (EBVaGC) and EBV-negative gastric carcinoma (EBVnGC) are largely unknown. Methods: To observe the correlation among TILs, TLS, and clinicopathological characteristics and their prognostic significance in EBVaGC and EBVnGC, respectively. TILs and TLS were assessed by morphology and/or immunohistochemistry, and accompanied by clinicopathological analysis from 846 gastric cancer patients in multiple institutions. Results: Forty-two (5.0%) cases of EBVaGC and 804 cases of EBVnGC were identified by in situ hybridization, respectively. For EBVnGC, higher TILs grade was correlated with TLS-present. EBVnGC patients with high TILs grade and TLS-present exhibited survival benefits. TILs (P = 0.001) and TLS (P = 0.003), especially TILs & TLS (P < 0.001) were independent prognostic factors in EBVnGC. A nomogram was constructed and validated for predicting the probability of overall survival and performed well with a good calibration. No significant prognostic value was detected in EBVaGC. Conclusion: TILs and TLS, especially TILs & TLS were promising prognostic indicators for overall survival in EBVnGC. TILs and TLS were highly overlapping in their extent and prognostic abilities, and may be considered as a coindicator of prognosis of gastric cancer. The evaluations of TILs and TLS are simple and can be assessed routinely in pathological diagnosis.

Transient Receptor Potential channels, TRPV1 and TRPA1 in melanocytes synergize UV-dependent and UV-independent melanogenesis.

BACKGROUND AND PURPOSE: Melanogenesis is essential for pigmentation and deregulated melanogenesis causes pigmentary diseases. Psoralen and ultraviolet A (PUVA) therapy strongly stimulates pigmentation, but the underlying molecular mechanisms are elusive. EXPERIMENTAL APPROACH: Melanin content of cultured human melanocytes was spectrophotometrically measured. Patch-clamp recordings were made in human melanocytes or HEK 293 cells transiently expressing wild type or mutant human TRPV1 and TRPA1 channels. Endogenous expression of TRPV1 and TRPA1 in melanocytes was analysed by western blotting and was knocked down with siRNA. In vivo pigmentary responses were measured by a colorimeter in mouse ear skin. The expression of TRPV1 and TRPA1 in human pigmented lesions was examined by immunohistochemical staining. KEY RESULTS: PUVA strongly stimulated melanogenesis and PUVA-induced TRPV1 and TRPA1 channel activation in melanocytes and the resulting Ca2+ influx were required for the stimulated melanogenesis both in vitro and in vivo. Agonists-induced TRPV1 and TRPA1 activation alone did not stimulate melanogenesis, but it synergized UVA or intrinsic cAMP and NO signalling pathways to stimulate UV-dependent or UV-independent melanogenesis. Moreover, the expressions of TRPV1 and TRPA1 were increased in human melanocytic lesions and inhibition of both channels decreased melanin content in melanoma cells. CONCLUSION AND IMPLICATIONS: TRPV1 and TRPA1 are key molecular sensors and enhancers of extrinsic and intrinsic melanogenic signals in both physiological and pathological conditions, and activation of both channels in melanocytes contributes to PUVA therapy-induced pigmentation. Our work provides a common mechanism of melanogenic regulation and highlights TRPV1 and TRPA1 as potential therapeutic targets for pigmentary disorders.

Development and Initial Validation of the Chinese Version of the Florida Surgical Questionnaire for Parkinson's Disease.

BACKGROUND: Deep brain stimulation (DBS) for Parkinson's disease (PD) has evolved as a well-established treatment in neurosurgery, and identifying appropriate surgical candidates could contribute to better DBS outcomes. The Florida Surgical Questionnaire for Parkinson Disease (FLASQ-PD) is a reasonable screening tool for assessing DBS candidacy in PD patients; however, a Chinese version of FLASQ-PD is needed for functional neurosurgery units in China. In this study, we translated the FLASQ-PD to Chinese and assessed its reliability and validity for Chinese PD patients. METHODS: The FLASQ-PD was translated before the study formally started. A single-center retrospective analysis of FLASQ-PD was performed at the Ruijin Hospital, affiliated with Shanghai Jiaotong University School of Medicine, between July and December 2019. The Unified Parkinson Disease Rating Scale III (UPDRS-III) was also used to assess PD patients on and off medication. All patients were evaluated for surgical candidacy by specialists. RESULTS: Overall, 115 PD patients, 25 with parkinsonism and six with multiple system atrophy were consecutively included. Internal consistency of the Chinese FLASQ-PD was roughly adequate (Cronbach's alpha = 0.664). There were significant differences in mean total scores of the Chinese FLASQ-PD between the diagnostic (Kruskal-Wallis H value = 37.450, p ≤ 0.001) and surgery-candidacy groups (H = 48.352, p ≤ 0.001). Drug improvements in UPDRS-III scores were mildly correlated with the Chinese FLASQ-PD scores in the surgery-ready group (Pearson correlation = 0.399, p=0.001). CONCLUSIONS: The Chinese FLASQ-PD, which is a simple and efficient screening tool for clinicians, was developed and initially validated in this retrospective single-center study.

EBV-miR-BART10-3p and EBV-miR-BART22 promote metastasis of EBV-associated gastric carcinoma by activating the canonical Wnt signaling pathway.

PURPOSE: Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) constitutes the largest subpopulation in EBV-associated tumors worldwide. To date, 44 mature EBV-encoded microRNAs (EBV miRNAs) have been identified, but their roles in EBVaGC development are still poorly understood. In this study, we aimed to investigate the roles and targets of ebv-miR-BART10-3p (BART10-3p) and ebv-miR-BART22 (BART22) in EBVaGC. METHODS: EBV miRNA expression in EBVaGCs was evaluated by deep sequencing and qRT-PCR, and relationships between BART10-3p or BART22 expression and clinicolpathological characteristics and survival rates of patients with EBVaGC were analyzed. The roles of BART10-3p and BART22 and their underlying mechanisms were further investigated through exogenous overexpression or silencing in EBVaGC cells, and validated in clinical EBVaGC tissue samples. RESULTS: BART10-3p and BART22 were found to be highly expressed in the EBVaGC cell lines SNU719 and YCCEL1. Higher expression of BART10-3p or BART22 in primary EBVaGC samples was significantly associated with lymph node metastasis and a worse 5-year overall survival. BART10-3p and BART22 promoted cell migration and invasion by targeting adenomatous polyposis coli (APC) and Dickkopf 1 (DKK1), thereby activating the Wnt signaling pathway and, consequently, upregulating downstream Twist and downregulating downstream E-cadherin. In 874 primary gastric carcinoma samples, APC and DKK1 were found to be lower expressed in EBVaGC than in EBV-negative samples, and their expression levels were inversely correlated with those of BART10-3p and BART22 in 71 EBVaGC samples. CONCLUSIONS: From our data we conclude that BART10-3p and BART22 play vital roles in promoting EBVaGC metastasis by targeting APC and DKK1 and, subsequently, activating the Wnt signaling pathway, thereby providing novel prognostic biomarkers and potential therapeutic targets for EBVaGC.

Differential expression of HER2 and downstream proteins in prediction of advanced tumor phenotypes and overall survival of patients with Epstein-Barr virus-positive vs. negative gastric cancers.

This study evaluated the associations of HER2 protein, HER2 gene amplification, and positivity for p-AKT, p-ERK, and p-PLCγ proteins with clinicopathological status and overall survival (OS) of patients who had Epstein-Barr virus-associated gastric cancer (EBVaGC; n = 58) or EBV-negative GC (EBVnGC; n = 329). Tissue samples were subjected to immunohistochemistry and fluorescence in situ hybridization (FISH). Results showed that EBVaGC less expressed HER2 and amplified HER2 gene. p-AKT (p =  0.035) and p-ERK (p =  0.001) were inhibited in EBVaGC than in EBVnGC, while p-PLCγ (p =  0.034) was upregulated. Among EBVaGC patients, p-ERK positivity was associated with Lauren classification (p = 0.023), and p-PLCγ positivity was inversely associated with TNM stage (p = 0.041) and lymph node metastasis (p = 0.041). In contrast, among EBVnGC patients, HER2 expression was associated with distant metastasis (p = 0.043) and p-AKT positivity was associated with intestinal subtype (p < 0.004), lymph node metastasis (p = 0.031), distant metastasis (p < 0.001), and elder age (>60y, p < 0.004). Overall analysis showed that EBVaGC patients presented better OS than EBVnGC patients (p = 0.044). Among EBVaGC patients, p-AKT positivity (p = 0.008) was associated with worse OS; as well as, HER2 high expression (p < 0.001), p-AKT positivity (p = 0.010), and p-PLCγ (p <  0.001) were associated with worse OS in EBVnGC patients. Multivariate analysis showed that distant metastasis (95% CI: 1.559 to 4.028, p <  0.001), HER2 high expression (95% CI: 1.058 to 2.454, p =  0.026), and p-PLCγ positivity (95% CI: 1.056 to 2.435, p = 0.027) were independent prognostic predictors of OS in EBVnGC patients. Our results indicated that p-AKT positive patients presented worse OS than p-AKT negative ones in EBVaGC, as well as, HER2, p-AKT, and p-PLCγ are prognostic biomarkers for OS in EBVnGC patients.

Clinical significance of spasmolytic polypeptide-expressing metaplasia and intestinal metaplasia in Epstein-Barr virus-associated and Epstein-Barr virus-negative gastric cancer.

Spasmolytic polypeptide-expressing metaplasia (SPEM) and intestinal metaplasia (IM) have been recognized as neoplastic precursors in gastric carcinogenesis. We explored the relationship between SPEM and IM in Epstein-Barr virus-associated (EBVaGC) and Epstein-Barr virus-negative (EBVnGC) gastric cancer. Sixty-four EBVaGC and one hundred and fifty-four EBVnGC patients were included. EBV positivity was identified using Epstein-Barr virus-encoded RNA-1 in situ hybridization. SPEM was subclassified into absent, early, and advanced SPEM. Acute and chronic inflammation was graded as absent, mild, moderate, and marked. Univariate and multivariate logistic regression analyses were conducted to analyze the correlation between SPEM, IM, and inflammation. Our study revealed that SPEM was detected in 87.5% EBVaGC and 85.1% EBVnGC patients. Distribution of patients according to the SPEM classification was significantly different between EBVaGC and EBVnGC groups (P=.038). IM was observed less frequently in EBVaGC when compared with EBVnGC patients (P<.001). No difference was observed between EBVaGC and EBVnGC in the levels of acute and chronic inflammation. A positive correlation between IM and SPEM status was observed in both EBVaGC and EBVnGC patients. Furthermore, advanced SPEM was an independent influential factor to IM in EBVnGC (P=.013). In conclusion, SPEM was associated with both EBVaGC and EBVnGC more frequently than IM. Moreover, advanced SPEM had a stronger association with IM than early SPEM in EBVnGC. These results suggest that identification of SPEM should be used as a high-risk indicator for detecting early gastric carcinoma, and should be brought to the attention of pathologists and clinicians.

Expression and prognostic roles of PIK3CA, JAK2, PD-L1, and PD-L2 in Epstein-Barr virus-associated gastric carcinoma.

As a special subtype of gastric carcinoma, Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) has distinct clinicopathological features. The Cancer Genome Atlas Research Network revealed that EBVaGC also has distinct molecular features: PIK3CA mutations, DNA hypermethylation, and JAK2, PD-L1, and PD-L2 amplification. Here, we evaluated PIK3CA, JAK2, PD-L1, and PD-L2 expression in 59 EBVaGC and 796 EBV-negative gastric carcinoma (EBVnGC) cases using immunohistochemistry and found that PIK3CA, JAK2, PD-L1, and PD-L2 were highly expressed in 75.9% and 48.8% (P<.001), 81.8% and 71.1% (P=.091), 92.5% and 84.8% (P=.132), and 98.1% and 89.7% (P=.049) of the EBVaGC and EBVnGC cases, respectively. However, the expression of PIK3CA, JAK2, PD-L1, or PD-L2 was not significantly associated with clinicopathological features or patient outcomes in EBVaGC. In contrast, in EBVnGC, high PIK3CA expression was significantly associated with indolent clinicopathological features and independently predicted better 5-year overall survival (57.8% versus 33.4%, P<.001). Our study indicated that the protein expression of the 4 characteristic molecules of EBVaGC was basically consistent with their genetic alterations, making them potential characteristic protein biomarkers and therapeutic targets of EBVaGC. The favorable impact of PIK3CA overexpression on survival found in this study gives us new insight into the clinical significance of PIK3CA in EBVnGC.

Accumulation Mechanisms of CD4(+)CD25(+)FOXP3(+) Regulatory T Cells in EBV-associated Gastric Carcinoma.

Approximately 10% of gastric carcinomas are associated with Epstein-Barr virus (EBV) and are defined as EBV-associated gastric carcinomas (EBVaGCs). EBVaGCs are known to be accompanied by massive CD8(+) cytotoxic T cell (CTL) infiltration; however, adoptive cellular immunotherapy based on EBV-specific CD8(+) CTLs has been explored with limited success. Because regulatory T cells (Tregs) are regarded as a critical hurdle in anti-tumour immunity, we assessed the distribution of Tregs in 45 cases of EBVaGC and 45 cases of EBV-negative gastric carcinoma (EBVnGC) with matched clinicopathological parameters by immunohistochemistry. We showed that Tregs were significantly increased in EBVaGC compared to EBVnGC (15.92 ± 11.45/HPF vs. 8.45 ± 6.16/HPF, p = 0.001). In addition, we explored the accumulation mechanisms of Tregs in EBVaGC by using EBV (+) gastric carcinoma cell lines SNU719 and GT39 as ex vivo models. When peripheral blood mononuclear cells (PBMCs) were co-cultured with EBV (+) gastric carcinoma cell lines, the Treg frequency increased, and they underwent phenotypic and functional changes. The enhanced recruitment by CCL22 produced by EBVaGC cells, the decreased emigration due to CCR7 downregulation on the Treg surface, the higher proliferation rate, and the lower apoptosis rate of Tregs at tumour sites may promote the accumulation of Tregs in EBVaGC.

Aberrant gene promoter methylation of p16, FHIT, CRBP1, WWOX, and DLC-1 in Epstein-Barr virus-associated gastric carcinomas.

Alterations in global DNA methylation and specific regulatory gene methylation are frequently found in cancer, but the significance of these epigenetic changes in EBV-associated gastric carcinoma (EBVaGC) remains unclear. We evaluated global DNA methylation status in 49 EBVaGC and 45 EBV-negative gastric carcinoma (EBVnGC) tissue samples and cell lines by 5-methylcytosine immunohistochemical staining and methylation quantification. We determined promoter methylation status and protein expression for the p16, FHIT, CRBP1, WWOX, and DLC-1 genes in tissues and studied the correlation between CpG island methylator phenotype (CIMP) class and clinicopathological characteristics. Changes in gene methylation and mRNA expression in EBVaGC cell line SNU-719 and in EBVnGC cell lines SGC-7901, BGC-823, and AGS were assessed after treatment with 5-aza-2'-deoxycytidine (5-aza-dC), trichostatin A (TSA), or a combination of both, by methylation-specific PCR and quantitative real-time RT-PCR. Global genomic DNA hypomethylation was more pronounced in EBVnGC than in EBVaGC. Promoter methylation of all five genes was more frequent in EBVaGC than in EBVnGC (p < 0.05). p16 and FHIT methylation was reversely correlated with protein expression in EBVaGC. Most (41/49) EBVaGC exhibited CIMP-high (CIMP-H), and the prognosis of CIMP-H patients was significantly worse than that of CIMP-low (p = 0.027) and CIMP-none (p = 0.003) patients. Treatment with 5-aza-dC and/or TSA induced upregulation of RNA expression of all five genes in SNU-719; meanwhile, individual gene expression increased in EBVnGC cell lines. In summary, EBV-induced hypermethylation of p16, FHIT, CRBP1, WWOX, and DLC-1 may contribute to EBVaGC development. Demethylation therapy may represent a novel therapeutic strategy for EBVaGC.

Epstein-Barr virus latent membrane protein 2A suppresses the expression of HER2 via a pathway involving TWIST and YB-1 in Epstein-Barr virus-associated gastric carcinomas.

To explore HER2 expression in Epstein-Barr virus-associated gastric carcinoma (EBVaGC) and the possible mechanisms causing down-regulation of HER2 expression in EBVaGC, we first evaluated HER2 and LMP2A expression on a clinicopathological-features matched cohort including 78 EBVaGC and 216 EBV-negative gastric carcinoma (EBVnGC) cases by immunohistochemistry. Cases with high HER2 expression in EBVaGC were significantly less than in EBVnGC (5.1% versus 23.7%; p<0.001), and none of the 34 LMP2A+ EBVaGC showed high HER2 expression. Further, overexpressing LMP2A in EBV-negative SGC7901 cells significantly decreased HER2, TWIST and YB-1 mRNA by 36.1%±8.1%, 87.6%±14.0% and 83.8%±5.7%, and protein by 44%, 57% and 49%, respectively. Additionally, the nucleus/cytoplasm ratios of TWIST and YB-1 were also decreased by 85% and 80%, respectively. Silencing LMP2A by siRNA in EBV-positive SNU719 cells for 48 h significantly increased HER2, TWIST and YB-1 mRNA to 276.7%±14.6%, 1284.8%±38.2% and 332.0%±15.5% and protein to 212%, 457% and 232%, respectively. The nucleus/cytoplasm ratios of TWIST and YB-1 were up-regulated by 4.00- and 3.57-fold, respectively, following LMP2A down-regulation. Moreover, LMP2A+/HER2low EBVaGC cases presented the best overall survival compared with LMP2A-/HER2low and LMP2A-/HER2high cases (p=0.003, log-rank test). These results suggest that LMP2A may suppress the HER2 expression through the TWIST/YB-1 axis in EBVaGC.