Significance of TFF3 protein and Her-2/neu status in patients with gastric adenocarcinoma

Augmented leptin-induced trefoil factor 3 expression and epidermal growth factor receptor transactivation differentially influences neoplasia progression in the stomach and colorectum of dietary fat-induced obese mice

Obesity is a risk factor for gastrointestinal malignancies and tumors. However, which factors either protect or predispose the gastrointestinal organs to high-fat diet (HFD)-induced neoplasia remains unclear. Here, we demonstrate that HFD impacts the stomach to a greater extent as compared to the colorectum, resulting in leptin receptor (LepR) signaling-mediated neoplasia in the tissues. HFD activated leptin signaling, which in turn, accelerates the pathogenesis in the gastric mucosa more than that in the colorectum along with ectopic TFF3 expression. Moreover, in the stomach, higher levels of phosphorylated epidermal growth factor receptor (EGFR) in addition to the activation of STAT3 and Akt were observed as compared to the colorectum. The mice with LepR deletion in the gastrointestinal epithelium exhibited a suppressed induction of leptin, TFF3, and phosphorylated EGFR in the stomach, whereas the levels in the colorectum were insignificant. In co-transfected COS-7 cells with LepR and EGFR plasmid DNA, leptin transactivated EGFR to accelerate TFF3 induction along with activation of STAT3, ERK1/2, Akt, and PI3K p85/p55. Furthermore, TFF3 could bind to EGFR but did not transactivate LepR. Leptin-induced TFF3 induction was markedly suppressed by inhibitors of PI3K (LY294002) and EGFR (Erlotinib). Together, these results suggest a novel role of LepR-mediated signaling in transactivating EGFR that leads to TFF3 expression via the PI3K-Akt pathway. Therefore, this study sheds light on the identification of potentially new therapeutic targets for the treatment of pre-cancerous symptoms in stomach and colorectum.

Gastric epithelial histology and precancerous conditions

The most common histological type of gastric cancer (GC) is gastric adenocarcinoma arising from the gastric epithelium. Less common variants include mesenchymal, lymphoproliferative and neuroendocrine neoplasms. The Lauren scheme classifies GC into intestinal type, diffuse type and mixed type. The WHO classification includes papillary, tubular, mucinous, poorly cohesive and mixed GC. Chronic atrophic gastritis (CAG) and intestinal metaplasia are recommended as common precancerous conditions. No definite precancerous condition of diffuse/poorly/undifferentiated type is recommended. Chronic superficial inflammation and hyperplasia of foveolar cells may be the focus. Presently, the management of early GC and precancerous conditions mainly relies on endoscopy including diagnosis, treatment and surveillance. Management of precancerous conditions promotes the early detection and treatment of early GC, and even prevent the occurrence of GC. In the review, precancerous conditions including CAG, metaplasia, foveolar hyperplasia and gastric hyperplastic polyps derived from the gastric epithelium have been concluded, based on the overview of gastric epithelial histological organization and its renewal.

The diagnostic and clinicopathological value of trefoil factor 3 in patients with gastric cancer: a systematic review and meta-analysis

OBJECTIVE

To assess the diagnostic value of Trefoil factor 3 (TFF3) and the correlation between TFF3 expression and clinicopathological features in patients with gastric cancer (GC).

METHODS

PubMed, The Cochrane, EMbase, and Web of Science were retrieved comprehensively to collect relevant literature. The search ended on 31 May 2020. All data were analyzed using PubMed, The Cochrane, EMbase, and Web of Science were retrieved to collect relevant articles. All data from the included studies were subjected to meta-analysis using Stata 12.0 software.

RESULTS

Seventeen studies involved 4654 subjects were included. For the diagnostic value of TFF3 for GC, the sensitivity, specificity, and AUC were 0.71, 0.80, and 0.80, respectively. For the clinicopathological value of TFF3, tissue TFF3 expression showed a higher risk of lymph node metastasis (OR 2.20, 95% CI 1.75-2.78, p < 0.001) and muscularis propria invasion (≥T2) (1.51, 1.13-2.03, p = 0.006), as well as worse TNM stage (2.26, 1.63-3.12, p < 0.001) and histological type (1.72, 1.34-2.20, p < 0.001), while no apparent relationship was found for serous membrane invasion (T4), venous invasion, and peritoneal metastasis.

CONCLUSION

TFF3 may be a promising biomarker for GC, and the TFF3 expression is likely to be involved in the invasion, metastasis, and differentiation of GC.

Effectiveness and Healthcare Cost of Adding Trastuzumab to Standard Chemotherapy for First-Line Treatment of Metastatic Gastric Cancer: A Population-Based Cohort Study

A randomized clinical trial showed that trastuzumab, added to traditional chemotherapy, significantly improved overall survival in human epidermal growth factor receptor 2 (HER2)-overexpressing metastatic gastric cancer patients. This population-based study aimed at evaluating both the clinical and economic impact of trastuzumab in a real-world setting. By using the healthcare utilization databases of Lombardy, Italy, a cohort of patients newly diagnosed with metastatic gastric cancer during the period 2011–2016 was selected. Among these, patients initially treated with either trastuzumab-based chemotherapy or standard chemotherapy alone were followed up until death, migration in other regions or June 2018. Overall survival and average cumulative costs were estimated and compared between the two treatment arms. Among the 1198 metastatic gastric cancer patients who started therapy within six months after metastasis detection, 87 were initially treated with trastuzumab-based chemotherapy and 1111 with standard chemotherapy. Median overall survival and restricted mean survival were 10.2 and 7.4 months, and 14.9 and 11.4 months, respectively, in the two treatment arms. The adjusted hazard ratio of death was 0.73 (95% CI 0.57–0.93). The average per capita cumulative healthcare costs were, respectively, EUR 39,337 and 26,504, corresponding to an incremental cost-effectiveness ratio of EUR 43,998 for each year of survival gained. Our study shows that adding trastuzumab to conventional chemotherapy is effective and cost-effective.

Release of HER2 repression of trefoil factor 3 (TFF3) expression mediates trastuzumab resistance in HER2+/ER+ mammary carcinoma

HER2+/ER+ breast cancer, a subset of the luminal B subtype, makes up approximately 10% of all breast cancers. The bidirectional crosstalk between HER2 and estrogen receptor (ER) in HER2+/ER+ breast cancer contributes to resistance towards both anti-estrogens and HER2-targeted therapies. TFF3 promotes breast cancer progression and has been implicated in anti-estrogen resistance in breast cancer. Herein, we investigated the cross-regulation between HER2 and estrogen-responsive TFF3, and the role of TFF3 in mediating trastuzumab resistance in HER2+/ER+ breast cancer. TFF3 expression was decreased by HER2 activation, and increased by inhibition of HER2 with trastuzumab in HER2+/ER+ breast cancer cells, partially in an ERα-independent manner. In contrast, the forced expression of TFF3 activated the entire HER family of receptor tyrosine kinases (HER1-4). Hence, HER2 negatively regulates its own signalling through the transcriptional repression of TFF3, while trastuzumab inhibition of HER2 results in increased TFF3 expression to compensate for the loss of HER2 signalling. In HER2+/ER+ breast cancer cells with acquired trastuzumab resistance, TFF3 expression was markedly upregulated and associated with a corresponding decrease in HER signalling. siRNA mediated depletion or small molecule inhibition of TFF3 decreased the survival and growth advantage of the trastuzumab resistant cells without re-sensitization to trastuzumab. Furthermore, TFF3 inhibition abrogated the enhanced cancer stem cell-like behaviour in trastuzumab resistant HER2+/ER+ breast cancer cells. Collectively, TFF3 may function as a potential biomarker and therapeutic target in trastuzumab resistant HER2+/ER+ breast cancer.

Evaluation of c-Met, HGF, and HER-2 expressions in gastric carcinoma and their association with other clinicopathological factors

Background

Met and HER-2 are proto-oncogenes encoding receptor tyrosine kinase c-Met and HER-2, respectively. Hepatocyte growth factor (HGF) is a ligand of c-Met. The frequency of c-Met, HGF, and HER-2 expressions in gastric cancer and their association with other clinicopathological factors have not been fully understood.

Patients and methods

Patients with stage 1–4 disease were analyzed. Expressions of c-Met, HGF, and HER-2 were examined using immunohistochemistry.

Results

A total of 143 patients, 97 males and 46 females, were included. C-Met scores were 3(+) in 31.5%, 2(+) in 27.3%, and 1(+) in 10.5% of the patients. There was no statistically significant difference in age, sex, tumor location, differentiation, Lauren classification, TNM staging, presence of distant metastasis, depth of tumor invasion (T), lymphovascular invasion, and survival between c-Met subgroups. Overall HGF positivity was 20.6%. HER-2 scores were 3(+) in 9.1%, 2(+) in 9.8%, and 1(+) in 16.1% of the patients. HER-2 overexpression was associated with better differentiation, intestinal subtype, and advanced stage. C-Met overexpressions were 84.6% in the HER-2-overexpression-positive group and 56.2% in the HER-2-overexpression-negative group. There were no statistically significant differences in survival between the high c-Met-expression-positive and -negative stage 3 and stage 4 patients and between the HGF-positive and -negative groups. The mean survival was 11.6±6.3 months in the HER-2-overexpression-positive stage 4 group and 11.9±6.8 months in the HER-2-overexpression-negative stage 4 group. There were no statistically significant differences in survival between the two groups.

Conclusion

c-Met was not associated with any prognostic factors in gastric cancer. HER-2 was associated with better differentiation, intestinal subtype, advanced stage, and c-Met overexpression.

Gastric biomarkers: a global review

BACKGROUND

Gastric cancer is an aggressive disease with a poor 5-year survival and large global burden of disease. The disease is biologically and genetically heterogeneous with a poorly understood carcinogenesis at the molecular level. Despite the many prognostic, predictive, and therapeutic biomarkers investigated to date, gastric cancer continues to be detected at an advanced stage with resultant poor clinical outcomes.

MAIN BODY

This is a global review of gastric biomarkers with an emphasis on HER2, E-cadherin, fibroblast growth factor receptor, mammalian target of rapamycin, and hepatocyte growth factor receptor as well as sections on microRNAs, long noncoding RNAs, matrix metalloproteinases, PD-L1, TP53, and microsatellite instability.

CONCLUSION

A deeper understanding of the pathogenesis and biological features of gastric cancer, including the identification and characterization of diagnostic, prognostic, predictive, and therapeutic biomarkers, hopefully will provide improved clinical outcomes.

Comparison of serum trefoil factor 3 with the pepsinogen test for the screening of diffuse-type gastric cancer

Emerging data show that serum trefoil factor 3 (TFF3) alone and combined with the serum pepsinogen (PG) test can increase the diagnostic yield of gastric cancer. We aimed to evaluate the diagnostic value of serum TFF3 for the screening of gastric cancer in Korean patients, especially for the screening of the diffuse type of gastric cancer, and compared TFF3 to the serum PG test. We enrolled 25 healthy controls and 79 subjects with gastric cancer who underwent endoscopic resection or surgery from June 2006 to June 2015. Data about age, sex, histological type according to the Lauren classification, stage of gastric cancer, and status of H. pylori were collected. Serum levels of PG I and PG II were measured by the latex-enhanced turbidimetric immunoassay, and serum TFF3 levels were measured by enzyme-linked immunosorbent assay. The optimal cutoff value of serum TFF3 was ≥8.9 ng/mL to diagnose gastric cancer, with 73.4 % sensitivity and 92.0 % specificity, which were higher than those of the serum PG I/II ratio, with 69.6 % sensitivity and 68.0 % specificity. The optimal sensitivity and specificity of serum TFF3 for the diagnosis of diffuse-type gastric cancer were 68.0 and 92.0 %, respectively, which were lower than those for the diagnosis of intestinal-type gastric cancer (75.6 and 100 %, respectively). Serum TFF3 is a more stable and useful marker than the serum PG test for the screening of gastric cancer in Korean patients. Serum TFF3 showed good diagnostic power in detecting both intestinal- and diffuse-type gastric cancer although it showed decreased power in diffuse type.

Concordance rate between HER2 immunohistochemistry and in situ hybridization in gastric carcinoma: systematic review and meta-analysis

PURPOSE

The aim of this study was to investigate the diagnostic accuracy of HER2 immunohistochemistry (IHC) in gastric carcinoma (GC) through a systematic review, meta-analysis and diagnostic test accuracy review.

METHOD

The current study included 12,679 GC cases and 181 subsets in 45 eligible studies. We performed concordance analysis between HER2 IHC and in situ hybridization (ISH) in GC. Diagnostic test accuracy was analyzed and the area under the curve (AUC) on the summary receiver operating characteristic (SROC) curve was calculated.

RESULTS

HER2 amplification rates were 3.0%, 31.8%, and 93.0% in the IHC score 0/1+, 2+, and 3+ groups, respectively. The concordance rates between IHC and ISH were 0.969 (95% confidence interval [CI] 0.962-0.975), 0.393 (95% CI 0.331-0.458) and 0.915 (95% CI 0.882-0.939) in the HER2 IHC score 0/1+, 2+, and 3+ groups, respectively. For all the HER2 IHC score groups, the positive rates were higher in the silver ISH (SISH) subgroup than in the fluorescence ISH (FISH) and chromogenic ISH (CISH) subgroups. In diagnostic test accuracy review, the pooled sensitivity and specificity were 0.86 (95% CI 0.84-0.87) and 0.91 (95% CI 0.90-0.91). The AUC on SROC curve was 0.958. However, there was no significant difference in the values of AUC between the ISH methods.

CONCLUSIONS

Our results showed that HER2 IHC was well concordant with ISH in HER2 IHC score 0/1+ or 3+. Although this meta-analysis showed higher diagnostic accuracy of HER2 IHC, more detailed criteria for HER2 IHC score 2+ cases will be required to predict HER2 status.

Clinical utility of HER2 assessed by immunohistochemistry in patients undergoing curative resection for gastric cancer

Purpose

We sought to determine whether human epidermal growth factor receptor 2 (HER2) and vascular endothelial growth factor (VEGF) expression were independent prognostic factors for gastric cancer (GC).

Patients and methods

A total of 678 consecutive patients with GC undergoing curative surgery between October 2010 and December 2012 had resected tissue examined for HER2 and VEGF expression using immunohistochemistry. Immunohistochemical expression of HER2 was analyzed using the DAKO-HercepTest™ and scored according to published reports. VEGF expression was calculated by multiplying the score for the percentage of positive cells by the intensity score. We defined positive expression as a score of 1+, 2+, or 3+, and a score of 0 was defined as negative expression. We compared these results to clinicopathological characteristics, including overall survival (OS).

Results

Multivariate analysis revealed that HER2 expression was independently associated with shorter OS (hazard ratio [HR], 1.55; 95% confidence interval [CI], 1.10–2.18; P=0.01) and with higher tumor–nodes–metastasis stage (HR, 3.88; 95% CI, 2.67–5.64; P<0.001) in patients with GC. VEGF expression was not associated with OS (HR, 1.25; 95% CI, 0.86–1.82; P=0.24). HER2 expression was still identified as an independent prognostic factor in Stage II–III patients treated with surgery and adjuvant chemotherapy (P=0.004) but not in patients who received surgery alone (P=0.61). Among patients with Stage III GC, those without HER2 expression survived longer with adjuvant chemotherapy (median 43.9 vs 32.2 months, respectively; P=0.04), whereas those with HER2 expression did not (median 37.1 vs 33.9 months, respectively; P=0.67).

Conclusion

HER2 expression is independently associated with OS in GC, especially in patients who are at higher risk and receive adjuvant chemotherapy after curative resection. HER2 expression may have important clinical utility in directing adjuvant treatment for Stage III GC patients.

Trefoil factors: Gastrointestinal-specific proteins associated with gastric cancer

Trefoil factor family (TFF), composed of TFF1, TFF2, and TFF3, is a cluster of secreted peptides characterized by trefoil domain (s) and C-terminal dimerization domain. TFF1, a gastric tumor suppressor, is a single trefoil peptide originally detected in breast cancer cell lines but expressed mainly in the stomach; TFF2, a candidate of gastric cancer suppressor with two trefoil domains, is abundant in the stomach and duodenal Brunner's glands; and TFF3 is another single trefoil peptide expressed throughout the intestine which can promote the development of gastric carcinoma. According to multiple studies, TFFs play a regulatory function in the mammals' digestive system, namely in mucosal protection and epithelial cell reconstruction, tumor suppression or promotion, signal transduction and the regulation of proliferation and apoptosis. Action mechanisms of TFFs remain unresolved, but the recent demonstration of a GKN (gastrokine) 2-TFF1 heterodimer implicates structural and functional interplay with gastrokines. This review aims to encapsulate the structural and biological characteristics of TFF.

Trefoil Factor 3 (TFF3) Is Regulated by Food Intake, Improves Glucose Tolerance and Induces Mucinous Metaplasia

Trefoil factor 3 (TFF3), also called intestinal trefoil factor or Itf, is a 59 amino acid peptide found as a homodimer predominantly along the gastrointestinal tract and in serum. TFF3 expression is elevated during gastrointestinal adenoma progression and has been shown to promote mucosal wound healing. Here we show that in contrast to other trefoil factor family members, TFF1 and TFF2, TFF3 is highly expressed in mouse duodenum, jejunum and ileum and that its expression is regulated by food intake. Overexpression of TFF3 using a recombinant adeno-associated virus (AAV) vector, or daily administration of recombinant TFF3 protein in vivo improved glucose tolerance in a diet-induced obesity mouse model. Body weight, fasting insulin, triglyceride, cholesterol and leptin levels were not affected by TFF3 treatment. Induction of mucinous metaplasia was observed in mice with AAV-mediated TFF3 overexpression, however, no such adverse histological effect was seen after the administration of recombinant TFF3 protein. Altogether these results suggest that the therapeutic potential of targeting TFF3 to treat T2D may be limited.

Trefoil factor 3 as a novel biomarker to distinguish between adenocarcinoma and squamous cell carcinoma

In carcinoma, such as of the lung, the histological subtype is important to select an appropriate therapeutic strategy for patients. However, carcinomas with poor differentiation cannot always be distinguished on the basis of morphology alone nor on clinical findings. Hence, delineation of poorly differentiated adenocarcinoma and squamous cell carcinoma, the 2 most common epithelial-origin carcinomas, is pivotal for selection of optimum therapy. Herein, we explored the potential utility of trefoil factor 3 (TFF3) as a biomarker for primary lung adenocarcinoma and extrapulmonary adenocarcinomas derived from different organs. We observed that 90.9% of lung adenocarcinomas were TFF3-positive, whereas no expression of TFF3 was observed in squamous cell carcinomas. The subtype of lung carcinoma was confirmed by four established biomarkers, cytokeratin 7 and thyroid transcription factor 1 for adenocarcinoma and P63 and cytokeratin 5/6 for squamous cell carcinoma. Furthermore, expression of TFF3 mRNA was observed by quantitative PCR in all of 11 human lung adenocarcinoma cell lines and highly correlated with markers of the adenocarcinomatous lineage. In contrast, little or no expression of TFF3 was observed in 4 lung squamous cell carcinoma cell lines. By use of forced expression, or siRNA-mediated depletion of TFF3, we determined that TFF3 appeared to maintain rather than promote glandular differentiation of lung carcinoma cells. In addition, TFF3 expression was also determined in adenocarcinomas from colorectum, stomach, cervix, esophagus, and larynx. Among all these extrapulmonary carcinomas, 93.7% of adenocarcinomas exhibited TFF3 positivity, whereas only 2.9% of squamous cell carcinomas were TFF3-positive. Totally, 92.9% of both pulmonary and extrapulmonary adenocarcinomas exhibited TFF3 positivity, whereas only 1.5% of squamous cell carcinomas were TFF3-positive. In conclusion, TFF3 is preferentially expressed in adenocarcinoma and may function as an additional biomarker for distinguishing adenocarcinoma from squamous cell carcinoma.

TFF3 and HER2 expression and their correlation with survival in gastric cancer

The molecular biomarkers human epidermal growth factor receptor-2 (HER2) and trefoil factor 3 (TFF3) are reported to play important roles in the pathogenesis of gastric cancer (GC). In this study, we investigated the clinicopathological and prognostic significance of TFF3 and HER2 expression in GC and explored the correlation between these two biomarkers. Ninety-two patients who were diagnosed with GC were enrolled. TFF3 and HER2 expression was determined on tumor tissues. The results showed that TFF3 and HER2 were positively expressed in 42.7 and 10.9% of the cases, respectively. There were significantly higher rates of TFF3 positivity in patients with deep invasive tumors and advanced stage ones. Patients with negative TFF3 staining survived longer than those with the presence of TFF3, with 5-year overall survival (OS) rates of 57.1 ± 7.1 and 39.5 ± 7.5%, respectively (P = 0.033). However, HER2 positivity was not significantly associated with OS (P = 0.262). Multivariate analysis demonstrated TFF3 expression to be an independent indicator for short-term survival, with a hazard ratio of 2.327 (95% confidence interval (CI), 1.202-4.507, P = 0.012). There was a trend that the expression of TFF3 was more frequent in HER2 negative tumors than in HER2 positive ones (positive rates: 16.3 vs. 4.7%, P = 0.098). Patients with HER2-negative/TFF3-negative GC presented higher OS than those with other phenotypes (P = 0.009). This study suggests that TFF3 is an independent indicator for survival in GC, while HER2 is not associated with the outcome. Patients with HER2-negative/TFF3-negative GC have the best outcome.

Trefoil factor 3 promotes metastatic seeding and predicts poor survival outcome of patients with mammary carcinoma

Introduction

Recurrence or early metastasis remains the predominant cause of mortality in patients with estrogen receptor positive (ER+) mammary carcinoma (MC). However, the molecular mechanisms underlying the initial progression of ER+ MC to metastasis remains poorly understood. Trefoil factor 3 (TFF3) is an estrogen-responsive oncogene in MC. Herein, we provide evidence for a functional role of TFF3 in metastatic progression of ER+ MC.

Methods

The association of TFF3 expression with clinicopathological parameters and survival outcome in a cohort of MC patients was assessed by immunohistochemistry. The expression of TFF3 in MCF7 and T47D cells was modulated by forced expression or siRNA-mediated depletion of TFF3. mRNA and protein levels were determined using qPCR and western blot. The functional effect of modulation of TFF3 expression in MC cells was determined in vitro and in vivo. Mechanistic analyses were performed using reporter constructs, modulation of signal transducer and activator of transcription 3 (STAT3) expression, and pharmacological inhibitors against c-SRC and STAT3 activity.

Results

TFF3 protein expression was positively associated with larger tumour size, lymph node metastasis, higher stage, and poor survival outcome. Forced expression of TFF3 in ER+ MC cells stimulated colony scattering, cell adhesion to a Collagen I-coated matrix, colony formation on a Collagen I- or Matrigel-coated matrix, endothelial cell adhesion, and transmigration through an endothelial cell barrier. In vivo, forced expression of TFF3 in MCF7 cells stimulated the formation of metastatic nodules in animal lungs. TFF3 regulation of the mRNA levels of epithelial, mesenchymal, and metastatic-related genes in ER+ MC cells were consistent with the altered cell behaviour. Forced expression of TFF3 in ER+ MC cells stimulated phosphorylation of c-SRC that subsequently increased STAT3 activity, which lead to the downregulation of E-cadherin. siRNA-mediated depletion of TFF3 reduced the invasiveness of ER+ MC cells.

Conclusions

TFF3 expression predicts metastasis and poor survival outcome of patients with MC and functionally stimulates cellular invasion and metastasis of ER+ MC cells. Adjuvant functional inhibition of TFF3 may therefore be considered to ameliorate outcome of ER+ MC patients.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-014-0429-3) contains supplementary material, which is available to authorized users.

Prognostic significance of the co-expression of nucleophosmin and trefoil factor 3 in postoperative gastric cancer patients

Although a number of studies have indicated that the positive expression of nucleophosmin (NPM) and trefoil factor 3 (TFF3) is associated with oncogenesis and poor prognosis in several tumor types, the prognostic value of the co-expression of NPM and TFF3 in gastric cancer (GC) has not been fully elucidated. Therefore, in this study, we aimed to investigate the role of NPM and TFF3 in GC and determine their prognostic value. We retrospectively reviewed 108 patients who had undergone radical gastric tumor resection. The expression of NPM and TFF3 was detected by immunohistochemistry and the association of NPM and TFF3 with clinicopathological characteristics was investigated using the Chi-square test. Furthermore, univariate and multivariate analyses were conducted to determine the prognostic value of these markers. Of the 108 samples, NPM was positive in 57 (53%) and TFF3 was positive in 54 samples (50%). The positive expression of NPM was correlated with advanced tumor stage and recurrence (P=0.0333 and P<0.0001, respectively), whereas the expression of TFF3 was associated with larger tumor size (P=0.0005), poor differentiation (P=0.0435), lymph node metastasis (P=0.0116), advanced tumor stage (P=0.0244) and recurrence (P=0.0116). The univariate analysis revealed that the expression of NPM, the expression of TFF3 and the co-expression of the two were associated with poor survival (P=0.0004, 0.0028 and 0.0020, respectively). By multivariate analysis, all three factors were identified as independent prognostic factors in postoperative GC patients (hazard ratio = 1.970, 2.021 and 2.339, respectively). In conclusion, the expression of NPM and TFF3 and, particularly, the co-expression of the two, may serve as independent prognostic factors in postoperative GC patients.

Prognostic significance of HER2 expression based on trastuzumab for gastric cancer (ToGA) criteria in gastric cancer: an updated meta-analysis

The prognostic significance of HER2 expression in patients with gastric cancer remains controversial, partially due to the significant heterogeneity of the approaches and criteria used for HER2 assessment among different studies. We therefore conducted a meta-analysis enrolling only studies defining HER2 status by trastuzumab for gastric cancer (ToGA) criteria. Published studies investigating the association between HER2 expression and survival were identified. Only publications that defined HER2 expression using ToGA criteria were enrolled. Meta-analyses were performed by Revman 5.2. Pooled hazard ratio (HR) and its 95 % confidence interval (CI) were calculated to evaluate the risk of disease. A total of 11 studies were enrolled in meta-analyses. Pooled data of nine studies using univariate analysis showed that HER2 expression is not associated with overall survival (OS; pooled HR, 0.97; 95 % CI, 0.84-1.12; P=0.63), which are maintained in six studies of multivariate analysis (pooled HR, 1.01; 95 % CI, 0.75-1.35; P=0.95). The Q statistic test for nine studies of univariate analysis and for six studies of multivariate analysis showed no and low heterogeneity (I (2)=22 % and P=0.25; I (2)=41 % and P=0.13, respectively). Furthermore, pooled data of four studies without heterogeneity (I (2)=0 %, P=0.74) showed that HER2 expression were not associated with relapse-free survival as well, with a pooled HR of 1.08 (95 % CI, 0.84-1.37; P=0.55) in patients with HER2 expression. In conclusion, this meta-analysis indicated that HER2 expression based on ToGA criteria is not related to the survival in patients with gastric cancer.

Altered expression of hypoxia-inducible factor-1α (HIF-1α) and its regulatory genes in gastric cancer tissues

Tissue hypoxia induces reprogramming of cell metabolism and may result in normal cell transformation and cancer progression. Hypoxia-inducible factor 1-alpha (HIF-1α), the key transcription factor, plays an important role in gastric cancer development and progression. This study aimed to investigate the underlying regulatory signaling pathway in gastric cancer using gastric cancer tissue specimens. The integration of gene expression profile and transcriptional regulatory element database (TRED) was pursued to identify HIF-1α ↔ NFκB1 → BRCA1 → STAT3 ← STAT1 gene pathways and their regulated genes. The data showed that there were 82 differentially expressed genes that could be regulated by these five transcription factors in gastric cancer tissues and these genes formed 95 regulation modes, among which seven genes (MMP1, TIMP1, TLR2, FCGR3A, IRF1, FAS, and TFF3) were hub molecules that are regulated at least by two of these five transcription factors simultaneously and were associated with hypoxia, inflammation, and immune disorder. Real-Time PCR and western blot showed increasing of HIF-1α in mRNA and protein levels as well as TIMP1, TFF3 in mRNA levels in gastric cancer tissues. The data are the first study to demonstrate HIF-1α-regulated transcription factors and their corresponding network genes in gastric cancer. Further study with a larger sample size and more functional experiments is needed to confirm these data and then translate into clinical biomarker discovery and treatment strategy for gastric cancer.