Gastric ulcer patients are more susceptible to developing gastric cancer compared with concomitant gastric and duodenal ulcer patients

YAP targetome reveals activation of SPEM in gastric pre-neoplastic progression and regeneration

Peptic ulcer disease caused by environmental factors increases the risk of developing gastric cancer (GC), one of the most common and deadly cancers in the world. However, the mechanisms underlying this association remain unclear. A major type of GC uniquely undergoes spasmolytic polypeptide-expressing metaplasia (SPEM) followed by intestinal metaplasia. Notably, intestinal-type GC patients with high levels of YAP signaling exhibit a lower survival rate and poor prognosis. YAP overexpression in gastric cells induces atrophy, metaplasia, and hyperproliferation, while its deletion in a Notch-activated gastric adenoma model suppresses them. By defining the YAP targetome genome-wide, we demonstrate that YAP binds to active chromatin elements of SPEM-related genes, which correlates with the activation of their expression in both metaplasia and ulcers. Single-cell analysis combined with our YAP signature reveals that YAP signaling is activated during SPEM, demonstrating YAP as a central regulator of SPEM in gastric neoplasia and regeneration.

Application of data mining methods to improve screening for the risk of early gastric cancer

BACKGROUND

Although gastric cancer is a malignancy with high morbidity and mortality in China, the survival rate of patients with early gastric cancer (EGC) is high after surgical resection. To strengthen diagnosing and screening is the key to improve the survival and life quality of patients with EGC. This study applied data mining methods to improve screening for the risk of EGC on the basis of noninvasive factors, and displayed important influence factors for the risk of EGC.

METHODS

The dataset was derived from a project of the First Hospital Affiliated Guangdong Pharmaceutical University. A series of questionnaire surveys, serological examinations and endoscopy plus pathology biopsy were conducted in 618 patients with gastric diseases. Their risk of EGC was categorized into low and high risk of EGC by the results of endoscopy plus pathology biopsy. The synthetic minority oversampling technique (SMOTE) was used to solve imbalance categories of the risk of EGC. Four classification models of the risk of EGC was established, including logistic regression (LR) and three data mining algorithms.

RESULTS

The three data mining models had higher accuracy than the LR model. Gain curves of the three data mining models were convexes more closer to ideal curves by contrast with that of the LR model. AUC of the three data mining models were larger than that of the LR model as well. The three data mining models predicted the risk of EGC more effectively in comparison with the LR model. Moreover, this study found 16 important influence factors for the risk of EGC, such as occupations, helicobacter pylori infection, drinking hot water and so on.

CONCLUSIONS

The three data mining models have optimal predictive behaviors over the LR model, therefore can effectively evaluate the risk of EGC and assist clinicians in improving the diagnosis and screening of EGC. Sixteen important influence factors for the risk of EGC were illustrated, which may helpfully assess gastric carcinogenesis, and remind to early prevention and early detection of gastric cancer. This study may also be conducive to clinical researchers in selecting and conducting the optimal predictive models.

Discriminating gastric cancer and gastric ulcer using human plasma amino acid metabolic profile

Patients with gastric ulcer (GU) have a significantly higher risk of developing gastric cancer (GC), especially within 2 years after diagnosis. The main way to improve the prognosis of GC is to predict the tumorigenesis and metastasis in the early stage. The objective of this study was to demonstrate the ability of human plasma amino acid metabolic profile for discriminating GC and GU. In this study, we first used liquid chromatography-tandem mass spectrometry technique to characterize the plasma amino acid metabolism in GC and GU patients. Plasma samples were collected from 84 GC patients and 82 GU patients, and 22 amino acids were detected in each patient. Partial least squares-discriminant analysis model was performed to analyze the data of these amino acids. We observed seven differential amino acids between GC and GU. A regression analysis model was established using these seven amino acids. Finally, a panel of five differential amino acids, including glutamine, ornithine, histidine, arginine and tryptophan, was identified for discriminating GC and GU with good specificity and sensitivity. The receiver operating characteristic curve was used to evaluate diagnostic ability of the regression model and area under the curve was 0.922. In conclusion, this study demonstrated the potential values of plasma amino acid metabolic profile and metabolomic analysis technique in assisting diagnosis of GC. More studies are needed to highlight the theoretical strengths of metabolomics to understand the potential metabolic mechanisms in GC. © 2018 IUBMB Life, 70(6):553-562, 2018.

Epithelial Regeneration After Gastric Ulceration Causes Prolonged Cell-Type Alterations

BACKGROUND & AIMS

The peptic ulcer heals through a complex process, although the ulcer relapse often occurs several years later after healing. Our hypothesis is that even after visual evidence of healing of gastric ulceration, the regenerated epithelium is aberrant for an extended interval, increasing susceptibility of the regenerated epithelium to damage and further diseases.

METHODS

Gastric ulcers were induced in mice by serosal topical application of acetic acid.

RESULTS

Gastric ulcers induced by acetic acid visually healed within 30 days. However, regenerated epithelial architecture was poor. The gene profile of regenerated tissue was abnormal, indicating increased stem/progenitor cells, deficient differentiated gastric cell types, and deranged cell homeostasis. Despite up-regulation of PDX1 in the regenerated epithelium, no mature antral cell type was observed. Four months after healing, the regenerated epithelium lacks parietal cells, trefoil factor 2 (TFF2) and (sex-determining region Y)-box 9 (SOX9) remain up-regulated deep in the gastric gland, and the Na/H exchanger 2 (a TFF2 effector in gastric healing) remains down-regulated. Gastric ulcer healing was strongly delayed in TFF2 knockout mice, and re-epithelialization was accompanied with mucous metaplasia. After Helicobacter pylori inoculum 30 days after ulceration, we observed that the gastric ulcer selectively relapses at the same site where it originally was induced. Follow-up evaluation at 8 months showed that the relapsed ulcer was not healed in H pylori-infected tissues.

CONCLUSIONS

These findings show that this macroscopically regenerated epithelium has prolonged abnormal cell distribution and is differentially susceptible to subsequent damage by H pylori.