Invertible and Variable Augmented Network for Pretreatment Patient-Specific Quality Assurance Dose Prediction.

Pretreatment patient-specific quality assurance (prePSQA) is conducted to confirm the accuracy of the radiotherapy dose delivered. However, the process of prePSQA measurement is time consuming and exacerbates the workload for medical physicists. The purpose of this work is to propose a novel deep learning (DL) network to improve the accuracy and efficiency of prePSQA. A modified invertible and variable augmented network was developed to predict the three-dimensional (3D) measurement-guided dose (MDose) distribution of 300 cancer patients who underwent volumetric modulated arc therapy (VMAT) between 2018 and 2021, in which 240 cases were randomly selected for training, and 60 for testing. For simplicity, the present approach was termed as "IVPSQA." The input data include CT images, radiotherapy dose exported from the treatment planning system, and MDose distribution extracted from the verification system. Adam algorithm was used for first-order gradient-based optimization of stochastic objective functions. The IVPSQA model obtained high-quality 3D prePSQA dose distribution maps in head and neck, chest, and abdomen cases, and outperformed the existing U-Net-based prediction approaches in terms of dose difference maps and horizontal profiles comparison. Moreover, quantitative evaluation metrics including SSIM, MSE, and MAE demonstrated that the proposed approach achieved a good agreement with ground truth and yield promising gains over other advanced methods. This study presented the first work on predicting 3D prePSQA dose distribution by using the IVPSQA model. The proposed method could be taken as a clinical guidance tool and help medical physicists to reduce the measurement work of prePSQA.

Annexin A7 and Its Related Protein Suppressor of Death Domains Regulates Migration and Proliferation of Hca-P Cells.

OBJECTIVE: This study was to investigate whether annexin A7 (AnnexinA7, ANXA7) and its co-related protein tumor cell death domain silencer [suppressor of death domains (SODD)] regulates the migratory phenotype of liver cancer cells. MATERIALS AND METHODS: In this experimental study, expression of ANXA7 in Hca-P cells, PANXA7 downregulated cells and PANXA7 unrelated sequence cells was detected by real-time quantitative polymerase chain reaction (PCR) at mRNA level and western blotting at protein level. Transwell migration and invasion assays were performed to determine the migratory phenotype. RESULTS: After inhibition of ANXA7 expression, expression of SODD protein was also significantly decreased (P<0.05). Transwell cell transfer experiments showed that number of tumor cells that penetrated into the cell membrane was significantly reduced after ANXA7 silencing (P<0.05). Transwell cell invasion assay showed that number of tumor cells penetrating into Matrigel was significantly reduced after ANXA7 down-regulation (P<0.05). The CCK8 assay was measured at 0, 24 and 48 hours, and proliferation rate of PANXA7 lower weir cells was slower than that of Hca-P cells and PANXA7 non-related sequence cells (P<0.05). CONCLUSION: SODD expression was decreased with the down-regulation of ANXA7. Down-regulating ANXA7 in Hca-P cells decreased proliferation, migration and invasion of tumor cells.

Exploration of tricyclic heterocycles as core structures for RIOK2 inhibitors.

Right open reading frame kinase 2 (RIOK2) is an atypical kinase and has been proved to be involved in multiple human cancers including non-small cell lung cancer (NSCLC), acute myeloid leukemia (AML), glioblastoma and anemia. Although tremendous efforts have been devoted to the studies of RIOK2, its biological functions remain poorly understood. It is highly important to develop potent and selective RIOK2 inhibitors as potential research tools to elucidate its functions and as drug candidates for further therapies. We have previously identified a highly potent and selective RIOK2 inhibitor (CQ211). To confirm the importance of the "V-shaped" structure of CQ211 for binding with RIOK2, a variety of tricyclic compounds with different core structures instead of the [1,2,3]triazolo[4,5-c]quinolin-4-one core of CQ211 were designed, synthesized, and the binding affinities of these tricyclic heterocycles with RIOK2 were also evaluated.

TransQA: deep hybrid transformer network for measurement-guided volumetric dose prediction of pre-treatment patient-specific quality assurance.

Objective. Performing pre-treatment patient-specific quality assurance (prePSQA) is considered an essential, time-consuming, and resource-intensive task for volumetric modulated arc radiotherapy (VMAT) which confirms the dose accuracy and ensure patient safety. Most current machine learning and deep learning approaches stack excessive convolutional/pooling operations (CPs) to predict prePSQA with two-dimensional or one-dimensional information input. However, these models generally present limitations in explicitly modeling long-range dependency for volumetric dose prediction due to the loss of spatial dose features and the inherent locality of CPs. The purpose of this work is to construct a deep hybrid network by combining the self-attention mechanism-based Transformer with modified U-Net for predicting measurement-guided volumetric dose (MDose) of prePSQA.Approach. The enrolled 307 cancer patients underwent VMAT were randomly divided into 246 and 61 cases for training and testing the model. The input data included computed tomography images, radiotherapy dose images exported from the treatment planning system, as well as the MDose distribution from the verification system. The output was the predicted high-quality voxel-wise prePSQA dose distribution.Main results: qualitative and quantitative experimental results show that the proposed prediction method could achieve comparable or better performance on MDose prediction over other approaches in terms of spatial dose distribution, dose-volume histogram metrics, gamma passing rates, mean absolute error, root mean square error, and structural similarity.Significance. The preliminary results on multiple cancer sites show that our approach can be taken as a clinical guidance tool and help medical physicists to reduce the measurement work of prePSQA.

JND4135, a New Type II TRK Inhibitor, Overcomes TRK xDFG and Other Mutation Resistance In Vitro and In Vivo.

The tropomyosin receptor kinases (TRKs) have been validated as effective targets in anticancer drug discovery. Two first-generation TRK inhibitors have been approved into market and displayed an encouraging therapeutic response in cancer patients harboring TRK fusion proteins. However, acquired resistance mediated by secondary TRK mutations especially in the xDFG motif remains an unsolved challenge in the clinic. Herein, we report the preclinical pharmacological results of JND4135, a new type II pan-TRK inhibitor, in overcoming TRK mutant resistance, including the xDFG mutations in vitro and in vivo. At a low nanomolar level, JND4135 displays a strong activity against wild-type TRKA/B/C and secondary mutations involving xDFG motif substitutions in kinase assays and cellular models; occupies the TRK proteins for an extended time; and has a slower dissociation rate than other TRK inhibitors. Moreover, by intraperitoneal injection, JND4135 exhibits tumor growth inhibition (TGI) of 81.0% at a dose of 40 mg/kg in BaF3-CD74-TRKA-G667C mice xenograft model. Therefore, JND4135 can be considered as a lead compound for drug discovery overcoming the resistance of TRK inhibitor drugs mediated by xDFG mutations.

Measurement of China's Green Total Factor Productivity Introducing Human Capital Composition.

In the face of resource and environmental problems caused by extensive economic development, China has put forward a green development strategy. Scientific measurement and analysis of green total factor productivity (GTFP) is of great significance for achieving high-quality economic development. By introducing the human capital composition, including education, health, scientific research, and training, this paper study adopts the Slack Based Measure-Global Malmquist-Luenberger (SBM-GML) index to re-measure the GTFP and its decomposition of 30 provinces, municipalities, and autonomous regions in China from 2000 to 2019. The results show that: (1) China's GTFP has a fluctuating growth trend, with an average annual growth rate of 2.31%. (2) In terms of its decomposition, technical progress is the main force driving GTFP growth, with a contribution rate of 1.59%; the improvement of technical efficiency is a secondary driving force, with a contribution rate of 0.71%. (3) The measurement results of GTFP, considering the human capital composition, are generally higher than those without consideration, and the GTFP growth under the two modes shows a trend of "high in the east and low in the west". The conclusions have enlightening significance for improving GTFP and the growth potential of the economy in China.

DNA Methylation-Specific Analysis of G Protein-Coupled Receptor-Related Genes in Pan-Cancer.

Tumor heterogeneity presents challenges for personalized diagnosis and treatment of cancer. The identification method of cancer-specific biomarkers has important applications for the diagnosis and treatment of cancer types. In this study, we analyzed the pan-cancer DNA methylation data from TCGA and GEO, and proposed a computational method to quantify the degree of specificity based on the level of DNA methylation of G protein-coupled receptor-related genes (GPCRs-related genes) and to identify specific GPCRs DNA methylation biomarkers (GRSDMs) in pan-cancer. Then, a ridge regression-based method was used to discover potential drugs through predicting the drug sensitivities of cancer samples. Finally, we predicted and verified 8 GRSDMs in adrenocortical carcinoma (ACC), rectum adenocarcinoma (READ), uveal Melanoma (UVM), thyroid carcinoma (THCA), and predicted 4 GRSDMs (F2RL3, DGKB, GRK5, PIK3R6) which were sensitive to 12 potential drugs. Our research provided a novel approach for the personalized diagnosis of cancer and informed individualized treatment decisions.

Expression Characteristics of SODD and ALG-2 as Possible Biomarkers for Evaluating Lymphatic Metastasis Potential of Hepatocarcinoma in a Mouse Model.

Annexin A7 has been confirmed in our previous research to be an important factor in lymph node metastasis (LNM) of hepatocellular carcinoma (HCC). SODD and ALG-2 are the binding proteins of Annexin A7 and can work in protein complexes. The present study was carried out with the constructed cell lines in mouse model of metastasis for further elaboration of possible mechanisms and identification of associated genes in the LNM of HCC. This experiment used inbred Chinese 615 mice, as well as Hca-F and Hca-P cells. Quantification of the relative messenger RNA (mRNA) expression of SODD and ALG-2 was realized by using qRT-PCR. Quantification of the protein expressions of SODD and ALG-2 was achieved by using western blot. Experimental mice (n=160) (6-8weeks old, 18-22g, SCXK [LIAO] 2008-0002) were randomly classified into four groups equally, which were separately inoculated with Hca-F, Hca-P, FAnxa7-upregulated, and PAnxa7-upregulated cells. Serum levels of SODD and ALG-2 were measured by ELISA. Immunohistochemical analysis of SODD and ALG-2 was further conducted. Tumor LNM-related factors of SODD and ALG-2 showed the same tendency in their expression correspondingly with the up-regulated expression of Annexin A7. Our experiment further explored the roles of SODD and ALG-2 based on Annexin A7 up-regulation vectors construction and the establishment of corresponding controls in vivo. Furthermore, the mouse model of primary tumors was constructed by injecting Hca-F, FAnxa7-upregulated and Hca-P, PAnxa7-upregulated cells into the mouse footpad. Mice were sacrificed at the designated time points for detecting SODD and ALG-2 expression in tumor tissue and serum samples. Collectively, our work indicates SODD in tumors and in serum and ALG-2 in serum are valuable in evaluating LNM in mice with HCC.

Expression and significance of miR-34 with PI3K, AKT and mTOR proteins in colorectal adenocarcinoma tissues.

This research was carried out to investigate the expression of miR-34a, miR-34b and p-PI3K, p-AKT, and mTOR proteins in colorectal adenocarcinoma and corresponding distal cutaneous normal mucosal tissues and their relationship with the clinicopathological parameters of colorectal adenocarcinoma as well as the correlation between miR-34a, miR-34b and PI3K/AKT/mTOR signaling pathway. The expression of p-PI3K, p-AKT, and mTOR proteins in 67 colorectal adenocarcinomas and the corresponding distal cut-off normal mucosa were assayed by immunohistochemistry. Their relationship with clinicopathological parameters and the correlation of the three proteins were evaluated. The expression of miR-34a and miR-34b in colorectal adenocarcinoma and the corresponding distal cutaneous normal mucosa was detected by applying real-time quantitative PCR. The correlation between colorectal adenocarcinoma tissue miR-34a, miR-34b and p-PI3K, p-AKT, and mTOR proteins, respectively, was analyzed. Results showed that the expression of p-PI3K, p-AKT and mTOR proteins in colorectal adenocarcinoma tissues was higher than that in the corresponding distal cutaneous normal mucosa (P=0.000), and there was a positive correlation between the expression of the three proteins in colorectal adenocarcinoma tissues. The expression of p-PI3K and p-AKT protein in colorectal adenocarcinoma tissues were correlated with tumor size, differentiation degree, infiltration degree, lymph node metastasis and TNM stage (P<0.05). The expression of mTOR protein was related to tumor size and differentiation degree (P<0.05). The relative expression of miR-34a and miR-34b in colorectal adenocarcinoma tissues was less than that in the corresponding distal cutaneous normal mucosa (P<0.05), and the expression of miR-34a and miR-34b was positively correlated. The expression of miR-34a and miR-34b in colorectal adenocarcinoma tissues was negatively correlated with the expression of p-PI3K, p-AKT and mTOR proteins. In conclusion, the PI3K/AKT/mTOR signaling pathway may promote colorectal adenocarcinoma and differentially participate in differentiation, infiltration and lymph node metastasis. Also, miR-34a and miR-34b may inhibit colorectal adenocarcinoma. Importantly, miR-34a and miR-34b may affect the development and progression of colorectal adenocarcinoma by regulating PI3K/AKT/mTOR signaling pathway.

MicroRNA-9 restrains the sharp increase and boost apoptosis of human acute myeloid leukemia cells by adjusting the Hippo/YAP signaling pathway.

MicroRNAs (miRNAs) play a very important role in the development of acute myeloid leukemia (AML). This study focuses on the effects of miR-9 on the regulation of AML cells and their related signaling pathways. We found that the expression of miR-9 was significantly decreased in four AML cell lines (THP-1, HL-60, TF-1 and KG-1) compared with the human normal bone marrow cells (HS-5). Moreover, miR-9 overexpression inhibited HL-60 cell proliferation ability, and promoted apoptosis. However, interfering with miR-9 expression promoted the proliferation of HL-6 cells and inhibited apoptosis. Western blotting results subsequently showed that overexpression of miR-9 could elevate the expression of MAT1, LATS1, and LATS2 in HL-60 cells, and inhibit the expression of YAP, while the interference with miR-9 had the opposite result. Taken together, miR-9 may act as a tumor suppressor by activating the Hippo/YAP signaling pathway of AML cells, which in this way supply ideas for the clinical remedy of AML patients.

A Novel Combined DNA Vaccine Encoding Toxoplasma gondii SAG1 and ROP18 Provokes Protective Immunity Against a Lethal Challenge in Mice.

PURPOSE: Antigens expressed by Toxoplasma gondii (T. gondii) during its life cycle trigger various immune responses in the host. Recently, toxoplasma vaccine research focused on T. gondii surface antigen 1 (SAG1) and Rhoptry Protein 18 (ROP18) to establish a safe and efficacious DNA vaccine. METHOD: We constructed two eukaryotic expression plasmids: p3 × FLAG-Myc-CMV™-24-SAG1 and p3 × FLAG-Myc-CMV™-24-ROP18. BALB/c mice were randomly divided into six groups and immunized with these DNA vaccines either separately or in combination. The combination vaccine was administered at either the full dose or at half-strength dose. Control mice were immunized with empty vector or with phosphate-buffered saline. RESULTS: The frequency of CD4+ cells in the spleen was consistent among all groups, whereas that of CD8+ T cells was the highest in the group immunized with the combination vaccine at half-strength dose (p < 0.05). Importantly, the mRNA expression levels of interleukin-12 (IL-12) and interferon-gamma (INF-γ) were closely correlated (r = 0.6, p < 0.0001) and both were upregulated in the group that was immunized with the combination vaccine at half-strength dose (p < 0.0001). The survival time of the mice subjected to a lethal dose of toxoplasma was significantly extended by prior immunization with DNA vaccines expressing either SAG1 or ROP18 or a combination of both (p < 0.05). The group that was immunized with the combination vaccine at half-strength dose demonstrated the best efficacy (p < 0.05). CONCLUSION: These results showed that the combination DNA vaccine provided better immune protection than the single gene vaccines, and that optimizing the dosing of the vaccine can improve the immune response.

Identification of U937JAK3-M511I Acute Myeloid Leukemia Cells as a Sensitive Model to JAK3 Inhibitor.

Mutated JAK3 has been considered a promising target for cancer therapy. Activating mutations of JAK3 are observed in 3.9%-10% of acute myeloid leukemia (AML) patients, but it is unclear whether AML cells are sensitive to JAK3 inhibitors, and no disease-related human AML cell model has been reported. We have identified U937 as the first human AML cell line expressing the JAK3M511I activated mutation and confirmed that JAK3 inhibitors sensitively suppress the proliferation of U937 AML cells.

H. pylori slyD, a novel virulence factor, is associated with Wnt pathway protein expression during gastric disease progression.

We have previously reported that the virulence factor HpslyD is related to the occurrence of gastric diseases. However, its mechanism of pathogenesis is still unclear. It is commonly believed that the Wnt/ß-catenin pathway is indispensable for the development of gastric cancer, but it is unclear whether HpslyD and Wnt/ß-catenin interact during the development of gastric diseases. Therefore, we measured the expression of E-cadherin, ß-catenin, TCF4, and CDX2 proteins by IHC in gastric mucosa specimens from patients with different gastric diseases and compared the differences in protein expression to H. pylori-infection status. The results indicated that the expression of these proteins was associated with HpslyD infection. HpslyD subtype infection, rather than common H. pylori infection, may have a greater effect on the expression of Wnt proteins in atrophic gastritis and gastric cancer. Additionally, HpslyD strain infection promoted the expression of Wnt pathway-related proteins with the progression of gastric disease. This study provides insight into the pathogenesis of H. pylori-related gastric diseases and "type-based treatment" for H. pylori infection.

Microbiological analysis of endotracheal aspirate and endotracheal tube cultures in mechanically ventilated patients.

BACKGROUND: To compare the microbiological culture within endotracheal aspirate specimens (ETAs) and endotracheal tube specimens (ETTs) in patients undergoing mechanical ventilation (MV) by statistical tools. METHOD: ETAs and ETTs from a total number of 81 patients, who were undergoing MV at the intensive care unit (ICU) of Jiading Central Hospital Affiliated Shanghai University of Medicine & Health Sciences from September 1st, 2017 to August 31st, 2018, were collected for microbiological culture analysis. Correlation of ETAs and ETTs cultures were obtained by Spear-men correlation analysis, while the consistency of the two specimens was determined by Kappa analysis and principal component analysis (PCA). RESULTS: Microbiological culture from both ETAs and ETTs showed that Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus, and Klebsiella pneumoniae were the main pathogens, with Spear-man correlation coefficients of 0.676, 0.951, 0.730 and 0.687 respectively (all P < 0.01), and the overall Spear-man correlation coefficient is 0.757 (P < 0.01). This result shows that two samples were positively correlated. Kappa analysis also revealed high consistency of the microbial culture results from the ETAs and the ETTs (overall κ = 0.751, P < 0.01). The κ values for the four bacteria detected were 0.670, 0.949, 0.723, and 0.687, respectively (all P < 0.001). PCA also revealed high similarity. CONCLUSION: Combining microbiological culture and statistical analysis of samples collected from 81 patients who were undergoing MV in ICU, we showed that microbe found in the ETAs had high similarity with that found in the ETTs which collected at the end of the catheters. In clinical practice, ETAs analysis is easily accessible meanwhile provides a valuable information for MV patients.

Poor short-term glycemic control in patients with type 2 diabetes impairs the intestinal mucosal barrier: a prospective, single-center, observational study.

BACKGROUND: To determine the relation between daily glycemic fluturation and the intestinal mucosal barrier dysfunction in type 2 diabetes mellitus (T2DM). METHODS: Totally 66 patients with T2DM were enrolled, 33 healthy volunteers were also recruited according to the enrolled patients' gender and age in a ratio of 2: 1. Patients were bisected by the median of endotoxins level into low(< 12.31 µ/l, n = 33) and high(≥12.31 µ/l, n = 33) blood endotoxin groups. Clinical data and blood glucose fluctuations were compared between groups. Multivariate regression analysis was used to determine the independent factors affecting the intestinal mucosal barrier. RESULTS: Serum endotoxin [12.1 (4.2~22.0) vs 3.2 (1.3~6.0), P < 0.001] and fasting blood glucose levels [9.8 ± 3.6 vs 5.4 ± 0.7, P < 0.001] were significantly higher in patients with T2DM than the control group. The standard deviation of blood glucose (SDBG) within 1 day [2.9 (2.0~3.3) vs. 2.1 (1.6~2.5), P = 0.012] and the largest amplitude of glycemic excursions (LAGE) [7.5 (5.4~8.9) vs. 5.9 (4.3~7.4), P = 0.034] were higher in the high endotoxin group than in the low endotoxin group. A multiple linear stepwise regression revealed a positive correlation between SDBG with endotoxin (standard partial regression coefficient = 0.255, P = 0.039). CONCLUSIONS: T2DM patients who incapable of maintaining stable blood glucose level are at a higher risk to associated with intestinal mucosal barrier injury.

HpSlyD inducing CDX2 and VIL1 expression mediated through TCTP protein may contribute to intestinal metaplasia in the stomach.

Helicobacter pylori infection is the most important risk factor for gastric intestinal metaplasia (IM). Our previous study demonstrated that infection with H. pylori HpslyD-positive strains associated with IM. To further investigate the signalling pathway involved in HpSlyD-induced IM, CDX2 and VIL1 expressions were determined before and after HpSlyD application. TCTP was knocked down by siRNA or overexpressed by plasmid transfection. An HpSlyD binding protein was used to block HpSlyD's enzymatic activity. The expression of CDX2 and TCTP in gastric diseases was measured by immunohistochemistry. Our results showed HpSlyD induced CDX2 and VIL1 expressions. TCTP protein expression was markedly increased after application of HpSlyD and in an HpSlyD-expressing stable cell line. Downregulation of TCTP protein led to decreased HpSlyD-induced CDX2 and VIL1. Overexpression of TCTP protein improved the expression of CDX2 and VIL1. Co-application of HpSlyD and FK506 led to significant reductions in CDX2, VIL1, and TCTP expression. Immunohistochemistry demonstrated that CDX2 and TCTP expression was higher in HpslyD-positive specimens compared with HpslyD-negative ones. Expression of CDX2 was positively correlated with TCTP in HpslyD-positive cells. Our study is the first to show that HpSlyD induction of CDX2 and VIL1 expression mediated through TCTP may contribute to IM in the stomach.

Snail promotes epithelial-mesenchymal transition and invasiveness in human ovarian cancer cells.

There are limited reports with respect to the study on the epithelium-mesenchymal transformation (EMT) mediated by Snail in the ovarian cancer. This study detected the expression of Snail and related EMT markers in the ovarian cancer tissues, and explored the possible molecular mechanism of EMT mediated by Snail in the metastasis of ovarian cancer. The patients diagnosed with ovarian cancer according to the pathology were recruited in this study during 2010-2014. The carcinoma tissue and normal tissue adjacent to carcinoma were surgically obtained from patients. The genes of E-cadherin, ß-catenin, Fibronectin and N-cadherin were detected using the RT-PCR. The 64 patients were recruited and diagnosed as ovarian cancer by pathological examination. The expression levels of Snail, Fibronectin and N-cadherin in the stage III and IV were higher than those in the stage I and II, respectively (all P < 0.05). However, the expression levels of E-cadherin and ß-catenin decreased along with the stage developed (trend test, both P < 0.05), respectively. The expression of Snail was positively correlated with the expression of Fibronectin, N-cadherin, but negatively correlated with the expression of E-cadherin and ß-catenin. The number of A2780 cells entering into the lower compartment in the group of carcinoma tissue were significantly higher than that in the group of normal tissue after transfected with Snail expression vector. While, the invasion ability of A2780 significantly reduced after RNAi-Snail. The correlation between Snail and invasion and metastasis of ovarian cancer and epithelial-mesenchymal transition based on tissue and cell levels, and to some extent explored the molecular mechanism of the EMT process mediated by Snail.

miR-204 inhibits invasion and epithelial-mesenchymal transition by targeting FOXM1 in esophageal cancer.

MicroRNAs (miRNAs), endogenous noncoding small RNAs, have been reported to play crucial roles in epithelial-mesenchymal transition (EMT) in cancers. Deregulation of microRNA-204 (miR-204) has been documented in many cancers, but its role in the development of esophageal cancer (EC) has not been studied. Here, we reported the role of miR-204 in invasion and EMT in EC. We identified an inverse correlation between miR-204 expression level and the invasion and EMT phenotype of EC cells, and up-regulation of miR-204 inhibited invasion and EMT phenotype of EC cells. Furthermore, we showed that forkhead box protein M1 (FOXM1) was a direct target gene of miR-204, and miR-204 regulated invasion and EMT in EC by acting directly on the 3'UTR of FOXM1 mRNA and suppressing its protein expression. We also explored the anti-tumor effect of miR-204, and found that overexpression of miR-204 suppressed the growth of esophageal tumors in vivo. These findings suggest that miR-204 might be a suppressor of invasion and EMT in EC, which offers a novel potential therapeutic target for EC.

Expression of the E-cadherin/ß-catenin/tcf-4 pathway in gastric diseases with relation to Helicobacter pylori infection: clinical and pathological implications.

OBJECTIVE: To determine the expression of E-cadherin, ß-catenin, and transcription factor 4 (TCF4) proteins in gastric diseases with relation to Helicobacter pylori infection. METHODS: A total of 309 patients including 60 with superficial gastritis (SG), 57 with atrophic gastritis (AG) and 192 with gastric cancer (GC), were enrolled. The expression of E-cadherin, ß-catenin, TCF4 proteins in the gastric mucosa was detected by immunohistochemistry and H. pylori infection by immunohistochemistry and PCR. RESULTS: The expression rates of E-cadherin were significantly higher in SG and AG than in GC (P<0.01), while those of ß-catenin in the nucleus were significantly lower in SG and AG than in GC (P<0.05). In GC cases, the expression rates of E-cadherin, ß-catenin and TCF4 were significantly higher in the intestinal type than in the diffuse type (P<0.05). In GC patients, the expression rate of E-cadherin was significantly higher in the presence of H. pylori than in the absence of infection (P=0.011). Moreover, the expression level of TCF4 and ß-catenin protein was significantly higher in the nucleus and cytoplasm in H. pylori positive than in H. pylori negative GC patients, especially in those with the intestinal type (all P < 0.05). CONCLUSION: The expression of E-cadherin and ß-catenin progressively decreases during the process of GC tumorigenesis, while overexpression of TCF4 occurs. H. pylori infection is associated with a significant increase in the expression of E-cadherin and ß-catenin in the cytoplasm and nucleus in GC patients, especially those with the intestinal type.

Helicobacter pylori induces malignant transformation of gastric epithelial cells in vitro.

Epidemiologic studies have demonstrated that Helicobacter pylori infection is associated with increased risk for the development of gastric cancer. Animal studies have also shown that H. pylori infection leads to gastric carcinogenesis, especially intestinal phenotypes. However, no in vitro study has been carried out for cell transformation induced by H. pylori. The present study aimed to investigate whether 'chronic'H. pylori infection induces gastric epithelial cell transformation, and elucidate the underlying mechanisms of transformation induced by H. pylori. The immortalized 'normal' gastric epithelial cell line, GES-1, was co-cultured for 45 days with H. pylori strains B975 and L301. The cell proliferation was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Ki-67 antigen, and colony formation assay. The cell transformation was determined by observing cell morphology and measuring the expression of E-cadherin, ß-catenin, and transcription factor-4 (TCF-4) at both protein and mRNA levels. H. pylori induced morphologic changes in GES-1 cells and significantly increased the proliferation of GES-1 cells. Moreover, H. pylori up-regulated the expression of ß-catenin and TCF-4, and also induced the nuclear accumulation of ß-catenin. In addition, the diffusive gastric cancer-related gene, E-cadherin, was up-regulated at the protein level, but down-regulated at the mRNA level. H. pylori infection is capable of inducing GES-1 transformation to present with the characteristics of intestinal-type gastric cancers in vitro, likely through the ß-catenin/TCF-4 signaling pathway.