Magnifying chromoendoscopy combined with immunohistochemical staining for early diagnosis of gastric cancer

Identification of ALDH3A2 as a novel prognostic biomarker in gastric adenocarcinoma using integrated bioinformatics analysis

Background

Extensive research has revealed that genes play a pivotal role in tumor development and growth. However, the underlying involvement of gene expression in gastric carcinoma (GC) remains to be investigated further.

Methods

In this study, we identified overlapping differentially expressed genes (DEGs) by comparing tumor tissue with adjacent normal tissue using the Gene Expression Omnibus (GEO) and the Cancer Genome Atlas (TCGA) database.

Results

Our analysis identified 79 up-regulated and ten down-regulated genes. Functional enrichment analysis and prognosis analysis were conducted on the identified genes, and the fatty aldehyde dehydrogenase (FALDH) gene, ALDH3A2, was chosen for more detailed analysis. We performed Gene Set Enrichment Analysis (GSEA) and immunocorrelation analysis (infiltration, copy number alterations, and checkpoints) to elucidate the mechanisms of action of ALDH3A2 in depth. The immunohistochemical (IHC) result based on 140 paraffin-embedded human GC samples indicated that ALDH3A2 was over-expressed in low-grade GC cases and the OS of patients with low expression of ALDH3A2 was significantly shorter than those with high ALDH3A2 expression. In vitro results indicated that the expression of ALDH3A2 was negatively correlated with PDCD1, PDCD1LG2, and CTLA-4.

Conclusion

We conclude that ALDH3A2 might be useful as a potential reference value for the relief and immunotherapy of GC, and also as an independent predictive marker for the prognosis of GC.

Interaction of Cyclooxygenase-2 with Helicobacter pylori Induces Gastric Chronic Nonresolving Inflammation and the Formation of Syndrome of Internal Block of Static Blood in Helicobacter pylori-Related Gastric Diseases

Cyclooxygenase-2 (COX-2) is an inducible enzyme stimulated by various inflammatory factors (IFs). Chronic gastritis is a classic model of “inflammation-cancer transformation” and Helicobacter pylori-related gastric diseases (HPGD) are specific ones of this model. Traditional Chinese Medicine (TCM) syndromes could play a predictive role in gastric histopathological evolution. To search for early warning evidence about “inflammation-cancer transformation,” this study is about to explore interaction of COX-2 with Helicobacter pylori (Hp) in HPGD with different TCM syndromes. All included subjects underwent endoscopy and biopsy. Hp infection was detected by rapid urease test and methylene blue staining. Histopathological characteristics and COX-2 expression in gastric mucosa (GM) were, respectively, observed by hematoxylin-eosin and Elivision™ plus. SPSS 18.0 and Stata 11.0 statistical software packages were used for statistical analysis. Results of immunohistochemical staining in this study showed COX-2 expression in Hp-positive patients was stronger than that in Hp-negative ones. Spearman' analysis indicated that degrees of both Hp infection and COX-2 expression were positively correlated with those of gastric inflammation and inflammatory activity. Compared with the relative normal group, both severe dysplasia group and gastric carcinoma group had more severe Hp infection and COX-2 expression. Compared with the nonsyndrome, syndrome of internal block of static blood (IBSB) had higher scores in semiquantitative analysis of COX-2 protein expression among TCM groups. Moreover, multivariate logistics regression analysis suggested that patients with Hp infection could increase the risk of IBSB. These results indicated that COX-2 interacting with Hp could play an important role in transforming gastric chronic nonresolving inflammation into carcinoma in subjects with HPGD, as well as inducing the formation of IBSB. HPGD together with IBSB could be an early warning evidence for GM with histopathological evolution from benign to malignant.

Protective effects of Weipixiao decoction against MNNG-induced gastric precancerous lesions in rats

Gastric cancer is recognized as one of the most common cancer. In-depth research of gastric precancerous lesions (GPL) plays an important role in preventing the occurrence of gastric cancer. Meanwhile, traditional treatment provides a novel sight in the prevention of occurrence and development of gastric cancer. The current study was designed to assess the effects of therapy with Weipixiao (WPX) decoction on N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced GPL rats and the underlying molecular mechanisms. After 10-weeks treatment, all rats were sacrificed. Histopathological changes of gastric tissue were assessed via hematoxylin-eosin (HE) and High-iron diamine-Alcian blue-Periodic acid-Schiff (HID-AB-PAS) staining. To be fully evidenced, RT-qPCR, Western blot and immunohistochemistry were used to detect the expressions of LDHA, CD147, HIF-1α, MCT4, PI3K, AKT, mTOR and miRNA-34a, which were crucial factors for evaluating GPL in the aspect of glycolysis pathogenesis. According to the results of HE and HID-AB-PAS staining, it could be confirmed that MNNG-induced GPL rats were obviously reversed by WPX decoction. Additionally, the increased gene levels of LDHA, CD147, MCT4, PI3K, AKT, mTOR and HIF-1α in model group were down-regulated by WPX decoction, while miRNA-34a expression was decreased and up-regulated by WPX decoction. The significantly increased protein levels of LDHA, CD147, MCT4, PI3K, AKT, mTOR and HIF-1α induced by MNNG were attenuated in rats treated with WPX decoction. In brief, the findings of this study imply that abnormal glycolysis in MNNG-induced GPL rats was relieved by WPX decoction via regulation of the expressions of LDHA, CD147, HIF-1α, MCT4, PI3K, AKT, mTOR and miRNA-34a.

Spectrum- and time-resolved endogenous multiphoton signals reveal quantitative differentiation of premalignant and malignant gastric mucosa

Early identification of premalignant and malignant gastric mucosa is crucial to decrease the incidence and mortality of stomach cancer. Spectrum- and time-resolved multiphoton microscopy are capable of providing not only structural but also biochemical information at the subcellular level. Based on this multidimensional imaging technique, we performed a systematic investigation on fresh human tissue specimens at the typical stages of gastric carcinogenesis, including normal, chronic gastritis with erosion, chronic gastritis with intestinal metaplasia, and intestinal-type adenocarcinoma. The results demonstrate that this technique is available to characterize the three-dimensional subcellular morphological and biochemical properties of gastric mucosa and further provide quantitative indicators of different gastric disorders, by using endogenous contrast. With advances in multiphoton endoscopy, it has the potential to allow noninvasive, label-free, real-time histological and functional diagnosis of premalignant and malignant lesions of stomach in the future.

Magnifying endoscopy simple diagnostic algorithm for early gastric cancer (MESDA-G)

Gastric cancer is the third leading cause of cancer death worldwide. Early detection and accurate diagnosis of mucosal cancer is desirable in order to achieve decreased mortality; cause-specific survival of patients with early gastric cancer is reported to exceed 95%. Endoscopy is the functional modality to detect early cancer; however, the procedure is not definitive when using conventional white-light imaging. In contrast, magnifying narrow-band imaging (M-NBI), a novel endoscopic technology, is a powerful tool for characterizing gastric mucosal lesions because it can visualize the microvascular architecture and microsurface structure. To date, many reports on the diagnosis of early gastric cancer by M-NBI, including multicenter prospective randomized studies conducted in Japan, have been published in peer-reviewed international journals. Based on these published data, we devised a proposal for a diagnostic strategy for gastric mucosal cancer using M-NBI to simplify the process of diagnosis and improve accuracy. Herein, we recommend a diagnostic algorithm for early gastric cancer using magnifying endoscopy.