Gastric Cancer Microbiome (original) (raw)
Related papers
Gastric Microbiota beyond H. pylori: An Emerging Critical Character in Gastric Carcinogenesis
Biomedicines
Gastric cancer (GC) is one of the global leading causes of cancer death. The association between Helicobacter pylori, which is a predominant risk factor for GC, with GC development has been well-studied. Recently, accumulating evidence has demonstrated the presence of a large population of microorganisms other than H. pylori in the human stomach. Existing sequencing studies have revealed microbial compositional and functional alterations in patients with GC and highlighted a progressive shift in the gastric microbiota in gastric carcinogenesis with marked enrichments of oral or intestinal commensals. Moreover, using a combination of gastric bacterial signatures, GC patients could be significantly distinguished from patients with gastritis. These findings, therefore, emphasize the importance of a collective microbial community in gastric carcinogenesis. Here, we provide an overview of non-H. pylori gastric microbes in gastric carcinogenesis. The molecular mechanisms of gastric microb...
Influence of the Microbiome Metagenomics and Epigenomics on Gastric Cancer
International Journal of Molecular Sciences
Gastric cancer (GC) is one of the major causes of cancer deaths worldwide. The disease is seldomly detected early and this limits treatment options. Because of its heterogeneous and complex nature, the disease remains poorly understood. The literature supports the contribution of the gut microbiome in the carcinogenesis and chemoresistance of GC. Drug resistance is the major challenge in GC therapy, occurring as a result of rewired metabolism. Metabolic rewiring stems from recurring genetic and epigenetic factors affecting cell development. The gut microbiome consists of pathogens such as H. pylori, which can foster both epigenetic alterations and mutagenesis on the host genome. Most of the bacteria implicated in GC development are Gram-negative, which makes it challenging to eradicate the disease. Gram-negative bacterium co-infections with viruses such as EBV are known as risk factors for GC. In this review, we discuss the role of microbiome-induced GC carcinogenesis. The disease r...
Revista Española de Enfermedades Digestivas, 2016
Background and Aim: Helicobacter pylori is the strongest risk factor for gastric cancer. However, recent advances in DNA sequencing technology have unraveled a complex microbial community in the stomach that can also participate in the development of gastric cancer. The aim of this study is to present recent scientific evidence regarding the role of non-Helicobacter pylori bacteria in gastric carcinogenesis. Methods: A systematic review of original articles published in PubMed in the last ten years related to gastric microbiota and gastric cancer was performed. Results: Thirteen original articles were included. The constitution of gastric microbiota appears to be significantly affected by gastric cancer and premalignant lesions as well as by Helicobacter pylori infection. In addition, a gradual shift in the gastric microbiota profile from non-atrophic gastritis to intestinal metaplasia, and then to intestinal type cancer appears to exist. Gastric carcinogenesis can be associated with an increase in many bacteria (such as Lactobacillus coleohominis, Klebsiella pneumoniae or Acinetobacter baumannii) as well a decrease in others (such as Porphyromonas spp, Neisseria spp, Prevotella pallens or Streptococcus sinensis). However, no conclusive data suggest if these changes in microbiota are cause or consequence of the process of carcinogenesis. Conclusions: Gastric cancer may be the result of a complex cross-talk between gastric microbiota and Helicobacter pylori. Gastric microbiota appears to play an important role in gastric carcinogenesis, beyond the well-known influence of Helicobacter pylori. Further studies are needed to elucidate the specific role of different microorganisms in the development of gastric cancer. This systematic review aims to provide an update of recent findings related to the role of gastric microbiota in gastric carcinogenesis, focusing on microorganisms besides H. pylori to understand how the constitution of microbiota can influence cancer risk and how it is affected by H. pylori status, possibly explaining its pathogenesis.
The Implication of Gastric Microbiome in the Treatment of Gastric Cancer
Cancers
Gastric cancer (GC) is one of the most common and deadly malignancies worldwide. Helicobacter pylori have been documented as a risk factor for GC. The development of sequencing technology has broadened the knowledge of the gastric microbiome, which is essential in maintaining homeostasis. Recent studies have demonstrated the involvement of the gastric microbiome in the development of GC. Therefore, the elucidation of the mechanism by which the gastric microbiome contributes to the development and progression of GC may improve GC’s prevention, diagnosis, and treatment. In this review, we discuss the current knowledge about changes in gastric microbial composition in GC patients, their role in carcinogenesis, the possible therapeutic role of the gastric microbiome, and its implications for current GC therapy.
Oral microbiota and Helicobacter pylori in gastric carcinogenesis: what do we know and where next?
BMC Microbiology, 2021
Gastric cancer (GC) is one of the most common malignancies causing death worldwide, and Helicobacter pylori is a powerful inducer of precancerous lesions and GC. The oral microbiota is a complex ecosystem and is responsible for maintaining homeostasis, modulating the immune system, and resisting pathogens. It has been proposed that the gastric microbiota of oral origin is involved in the development and progression of GC. Nevertheless, the causal relationship between oral microbiota and GC and the role of H. pylori in this relationship is still controversial. This study was set to review the investigations done on oral microbiota and analyze various lines of evidence regarding the role of oral microbiota in GC, to date. Also, we discussed the interaction and relationship between H. pylori and oral microbiota in GC and the current understanding with regard to the underlying mechanisms of oral microbiota in carcinogenesis. More importantly, detecting the patterns of interaction betwee...
Molecular Characterization of the Human Stomach Microbiota in Gastric Cancer Patients
Frontiers in cellular and infection microbiology, 2017
Helicobacter pylori (Hp) is the primary cause of gastric cancer but we know little of its relative abundance and other microbes in the stomach, especially at the time of gastric cancer diagnosis. Here we characterized the taxonomic and derived functional profiles of gastric microbiota in two different sets of gastric cancer patients, and compared them with microbial profiles in other body sites. Paired non-malignant and tumor tissues were sampled from 160 gastric cancer patients with 80 from China and 80 from Mexico. The 16S rRNA gene V3-V4 region was sequenced using MiSeq platform for taxonomic profiles. PICRUSt was used to predict functional profiles. Human Microbiome Project was used for comparison. We showed that Hp is the most abundant member of gastric microbiota in both Chinese and Mexican samples (51 and 24%, respectively), followed by oral-associated bacteria. Taxonomic (phylum-level) profiles of stomach microbiota resembled oral microbiota, especially when the Helicobacter...
Mucosal microbiome dysbiosis in gastric carcinogenesis
Gut, 2017
We aimed to characterise the microbial changes associated with histological stages of gastric tumourigenesis. We performed 16S rRNA gene analysis of gastric mucosal samples from 81 cases including superficial gastritis (SG), atrophic gastritis (AG), intestinal metaplasia (IM) and gastric cancer (GC) from Xi'an, China, to determine mucosal microbiome dysbiosis across stages of GC. We validated the results in mucosal samples of 126 cases from Inner Mongolia, China. We observed significant mucosa microbial dysbiosis in IM and GC subjects, with significant enrichment of 21 and depletion of 10 bacterial taxa in GC compared with SG (q<0.05). Microbial network analysis showed increasing correlation strengths among them with disease progression (p<0.001). Five GC-enriched bacterial taxa whose species identifications correspond to Peptostreptococcus stomatis, Streptococcus anginosus, Parvimonas micra, Slackia exigua and Dialister pneumosintes had significant centralities in the GC ...
Scientific reports, 2016
Inhabitants of Túquerres in the Colombian Andes have a 25-fold higher risk of gastric cancer than inhabitants of the coastal town Tumaco, despite similar H. pylori prevalences. The gastric microbiota was recently shown in animal models to accelerate the development of H. pylori-induced precancerous lesions. 20 individuals from each town, matched for age and sex, were selected, and gastric microbiota analyses were performed by deep sequencing of amplified 16S rDNA. In parallel, analyses of H. pylori status, carriage of the cag pathogenicity island and assignment of H. pylori to phylogeographic groups were performed to test for correlations between H. pylori strain properties and microbiota composition. The gastric microbiota composition was highly variable between individuals, but showed a significant correlation with the town of origin. Multiple OTUs were detected exclusively in either Tumaco or Túquerres. Two operational taxonomic units (OTUs), Leptotrichia wadei and a Veillonella ...
Frontiers in cellular and infection microbiology, 2018
Eradication of has been found to be effective for gastric cancer prevention, but uncertainties remain about the possible adverse consequences such as the potential microbial dysbiosis. In our study, we investigated the association between gut microbiota and -related gastric lesions in 47 subjects by deep sequencing of microbial 16S ribosomal RNA (rRNA) gene in fecal samples. The dominant phyla in fecal samples were , and with average relative abundances of 54.77, 31.37 and 12.91%, respectively. Microbial diversity analysis showed that observed species and Shannon index were increased in subjects with past or current infection compared with negative subjects. As for the differential bacteria, the average relative abundance of was found to significantly decrease from negative (66.16%) to past infection group (33.01%, = 0.007), as well as from normal (76.49%) to gastritis (56.04%) and metaplasia subjects (46.83%, = 0.027). For and , the average relative abundances showed elevated trend...