Prognostic Value of Trefoil Factor 3 Expression in Patients with Gastric Cancer

Unveiling Gene Regulatory Networks That Characterize Difference of Molecular Interplays Between Gastric Cancer Drug Sensitive and Resistance Cell Lines

Gastric cancer is a leading cause of cancer-related deaths globally and chemotherapy is widely accepted as the standard treatment for gastric cancer. However, drug resistance in cancer cells poses a significant obstacle to the success of chemotherapy, limiting its effectiveness in treating gastric cancer. Although many studies have been conducted to unravel the mechanisms of acquired drug resistance, the existing studies were based on abnormalities of a single gene, that is, differential gene expression (DGE) analysis. Single gene-based analysis alone is insufficient to comprehensively understand the mechanisms of drug resistance in cancer cells, because the underlying processes of the mechanism involve perturbations of the molecular interactions. To uncover the mechanism of acquired gastric cancer drug resistance, we perform for identification of differentially regulated gene networks between drug-sensitive and drug-resistant cell lines. We develop a computational strategy for identifying phenotype-specific gene networks by extending the existing method, CIdrgn, that quantifies the dissimilarity of gene networks based on comprehensive information of network structure, that is, regulatory effect between genes, structure of edge, and expression levels of genes. To enhance the efficiency of identifying differentially regulated gene networks and improve the biological relevance of our findings, we integrate additional information and incorporate knowledge of network biology, such as hubness of genes and weighted adjacency matrices. The outstanding capabilities of the developed strategy are validated through Monte Carlo simulations. By using our strategy, we uncover gene regulatory networks that specifically capture the molecular interplays distinguishing drug-sensitive and drug-resistant profiles in gastric cancer. The reliability and significance of the identified drug-sensitive and resistance-specific gene networks, as well as their related markers, are verified through literature. Our analysis for differentially regulated gene network identification has the capacity to characterize the drug-sensitive and resistance-specific molecular interplays related to mechanisms of acquired drug resistance that cannot be revealed by analysis based solely on abnormalities of a single gene, for example, DGE analysis. Through our analysis and comprehensive examination of relevant literature, we suggest that targeting the suppressors of the identified drug-resistant markers, such as the Melanoma Antigen (MAGE) family, Trefoil Factor (TFF) family, and Ras-Associated Binding 25 (RAB25), while enhancing the expression of inducers of the drug sensitivity markers [e.g., Serum Amyloid A (SAA) family], could potentially reduce drug resistance and enhance the effectiveness of chemotherapy for gastric cancer. We expect that the developed strategy will serve as a useful tool for uncovering cancer-related phenotype-specific gene regulatory networks that provide essential clues for uncovering not only drug resistance mechanisms but also complex biological systems of cancer.

Overexpression of BRD4 in Gastric Cancer and its Clinical Significance as a Novel Therapeutic Target

BACKGROUND

BRD4 is a member of the bromodomain and extra terminal domain (BET) family of proteins, containing two bromodomains and one extra terminal domain, and is overexpressed in several human malignancies. However, its expression in gastric cancer has not yet been well illustrated.

OBJECTIVE

This study aimed to elucidate the overexpression of BRD4 in gastric cancer and its clinical significance as a novel therapeutic target.

METHODS

Fresh gastric cancer tissues and paraffin-embedded specimens of gastric cancer patients were collected, and the BRD4 expression was examined by Western Blot Analysis (WB) and Immunohistochemistry Analysis (IHC), respectively. The possible relationship between BRD4 expression and the clinicopathological features as well as survival in gastric cancer patients was analyzed. The effect of BRD4 silencing on human gastric cancer cell lines was investigated by MTT assay, WB, wound healing assay, and Transwell invasion.

RESULTS

The results showed that the expression level in tumor tissues and adjacent tissues was significantly higher than that in normal tissues, respectively (P < 0.01). BRD4 expression level in gastric cancer tissues was strongly correlated with the degree of tumor differentiated degree (P = 0.033), regional lymph nodes metastasis (P = 0.038), clinical staging (P = 0.002), and survival situation (P = 0.000), while the gender (P = 0.564), age (P = 0.926) and infiltrating depth (P = 0.619) of patients were not associated. Increased BRD4 expression resulted in poor overall survival (P = 0.003). In in vitro assays, BRD4 small interfering RNA resulted in significantly decreased BRD4 protein expression, therefore inhibiting proliferation, migration, and invasion of gastric cancer cells.

CONCLUSION

BRD4 might be a novel biomarker for the early diagnosis, prognosis, and therapeutic target in gastric cancer.

Trefoil factor 3 promotes pancreatic carcinoma progression via WNT pathway activation mediated by enhanced WNT ligand expression

Pancreatic ductal adenocarcinoma (PDAC) is a major cause of cancer-related mortality with a dismal prognosis that has changed little over the past few decades. Further understanding of the molecular pathology of PDAC progression is urgently required in order to improve the prognosis of patients with PDAC. Herein, it was observed that trefoil factor 3 (TFF3) expression was elevated in PDAC, and was positively correlated with a worse overall patient survival outcome. Forced expression of TFF3 promoted oncogenic functions of PDAC cells in vitro including cell proliferation, survival, foci formation, cancer stem cell-like behavior and invasion, ex vivo colony growth in 3D-Matrigel, and xenograft growth in vivo. Depletion or pharmacological inhibition of TFF3 inhibited these same processes. RNA-Seq analysis and subsequent mechanistic analyses demonstrated that TFF3 increased the expression of various WNT ligands to mediate WNT pathway activation required for TFF3-stimulated PDAC progression. Combined pharmacological inhibition of TFF3 and WNT signaling significantly attenuated PDAC xenograft growth and potentiated the therapeutic efficacy of gemcitabine in both ex vivo and in vivo models. Hence, a mechanistic basis for combined inhibition of pathways enhancing PDAC progression is provided and suggests that inhibition of TFF3 may assist to ameliorate outcomes in PDAC.

Early detection of gastric cancer beyond endoscopy - new methods

Early detection of gastric cancer is remaining a challenge. This review summarizes current knowledge on non-invasive methods that could be used for the purpose. The role of traditional cancer markers such as CEA, CA 72-4, CA 19-9, CA 15-3, and CA 12-5 lies mainly in therapy monitoring than early detection. Most extensive studied biomarkers (pepsinogens, ABC method) are aiming at the detection of precancerous lesions with modest sensitivity for cancer. Tests based on the detection of cancer-specific methylation patterns (PanSeer), circulating proteins and mutations in circulating tumour DNA (CancerSEEK), as well as miRNA panels have demonstrated promising results bringing those closer to practice. More extensive research is required before tests based on the detection of circulating tumour cells, extracellular vesicles and cell-free RNA could reach the practice. Detection of volatile organic compounds in the human breath is a promising development; sensor technologies for this purpose could be very attractive in screening settings.

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.

Pretreatment with intestinal trefoil factor alleviates stress-induced gastric mucosal damage via Akt signaling

BACKGROUND

Stress-related gastric mucosal damage or ulcer remains an unsolved issue for critically ill patients. Stress ulcer prophylaxis has been part of routine intensive care, but uncertainty and controversy still exist. Co-secreted with mucins, intestinal trefoil factor (ITF) is reported to promote restitution and regeneration of intestinal mucosal epithelium, although the mechanism remains unknown.

AIM

To elucidate the protective effects of ITF on gastric mucosa and explore the possible mechanisms.

METHODS

We used a rat model of gastric mucosal damage induced by water immersion restraint stress and lipopolysaccharide-treated human gastric epithelial cell line to investigate the potential effects of ITF on damaged gastric mucosa both in vivo and in vitro.

RESULTS

ITF promoted the proliferation and migration and inhibited necrosis of gastric mucosal epithelia in vitro. It also preserved the integrity of gastric mucosa by upregulating expressions of occludin and zonula occludens-1. In the rat model, pretreatment with ITF ameliorated the gastric mucosal epithelial damage and facilitated mucosal repair. The protective effects of ITF were confirmed to be exerted via activation of Akt signaling, and the specific inhibitor of Akt signaling LY249002 reversed the protective effects.

CONCLUSION

ITF might be a promising candidate for prevention and treatment of stress-induced gastric mucosal damage, and further studies should be undertaken to verify its clinical feasibility.

The expression of trefoil factor 3 is related to histologic subtypes and invasiveness in lung adenocarcinoma

Adenocarcinoma is the most common histological type of lung cancer and has various histologic subtypes, including lepidic, papillary, acinar and invasive mucinous adenocarcinoma. Histologic subtypes are associated with tumor invasiveness. For example, the lepidic subtype is less invasive than the papillary/acinar subtype. Trefoil factor 3 (TFF3) is a small secreting protein that is a member of the trefoil factor family, which is involved in mucosal stabilization and repair through its mitogenic and antiapoptotic activities. TFF3 overexpression is associated with various types of cancer. In lung cancer, TFF3 is expressed significantly in adenocarcinoma. However, the relationship between TFF3 expression and histologic subtypes in lung adenocarcinoma is unclear. The current study immunohistochemically revealed that, beside invasive mucinous carcinoma, the expression of TFF3 in papillary and acinar adenocarcinoma was significantly higher than that in lepidic adenocarcinoma. To further confirm these results, the expression of TFF3 in cases with both lepidic and papillary/acinar areas were examined. The expression of TFF3 in papillary/acinar areas was significantly higher when compared with lepidic areas in a single sample. Furthermore, using the lung adenocarcinoma cell line A549, TFF3-knockdown cells were generated. The results revealed that knockdown of TFF3 attenuated invasion. In vitro and immunohistochemical assays using clinical samples demonstrated that TFF3 expression was associated with lung adenocarcinoma invasiveness. To the best of our knowledge, the current study is the first to report that TFF3 expression was associated with the histologic subtypes of lung adenocarcinoma.

scPred: accurate supervised method for cell-type classification from single-cell RNA-seq data

Single-cell RNA sequencing has enabled the characterization of highly specific cell types in many tissues, as well as both primary and stem cell-derived cell lines. An important facet of these studies is the ability to identify the transcriptional signatures that define a cell type or state. In theory, this information can be used to classify an individual cell based on its transcriptional profile. Here, we present scPred, a new generalizable method that is able to provide highly accurate classification of single cells, using a combination of unbiased feature selection from a reduced-dimension space, and machine-learning probability-based prediction method. We apply scPred to scRNA-seq data from pancreatic tissue, mononuclear cells, colorectal tumor biopsies, and circulating dendritic cells and show that scPred is able to classify individual cells with high accuracy. The generalized method is available at https://github.com/powellgenomicslab/scPred/.

The Long Non-Coding RNA ENST00000489676 Influences Papillary Thyroid Cancer Cell Proliferation and Invasion through Regulating MiR-922

Purpose: Long noncoding RNAs (lncRNAs) have been reported to be associated with the growth and progression of numerous cancers. The aim of this study was to explore the potential function and molecular mechanism of lncRNA ENST00000489676 in the proliferation and invasion of papillary thyroid cancer (PTC). Methods: QRT-PCR (quantitative reverse transcriptase-polymerase chain reaction) was used to determine the levels of ENST00000489676. CCK-8 (Cell Counting Kit-8) assay and colony formation assay were performed to detect the cell proliferation. Flow cytometry was used to analyze the cell cycle. Transwell and scratch assay were performed to detect the migration and invasion ability. Results: The expression of ENST00000489676 was significantly overexpressed in TPC1 compared to KTC1 cell lines. When ENST00000489676 expression was knocked down, the proliferation, migration and invasion ability as well as cell cycle were all promoted in PTC cell lines, while those abilities were all suppressed when ENST00000489676 overexpressed. Overexpression of ENST00000489676 could inhibit cell proliferation, migration and invasion in vitro. Moreover, ENST00000489676 may mediate tumor suppression in PTC cells through suppressing miR-922. Conclusions: ENST00000489676 negatively regulated the proliferation, migration invasion and cell cycle of PTC. The overexpression of ENST00000489676 inhibited the progression of PTC through suppressing miR-922. ENST00000489676 could be act as a novel diagnosis marker and a potential therapeutic target for PTC.