Helicobacter pylori infection(Hp-I)represents a typical microbial agent intervening in the complex mechanisms of gastric homeostasis by disturbing the balance between the host gastric microbiota and mucosa-related fac...Helicobacter pylori infection(Hp-I)represents a typical microbial agent intervening in the complex mechanisms of gastric homeostasis by disturbing the balance between the host gastric microbiota and mucosa-related factors,leading to inflammatory changes,dysbiosis and eventually gastric cancer.The normal gastric microbiota shows diversity,with Proteobacteria[Helicobacter pylori(H.pylori)belongs to this family],Firmicutes,Actinobacteria,Bacteroides and Fusobacteria being the most abundant phyla.Most studies indicate that H.pylori has inhibitory effects on the colonization of other bacteria,harboring a lower diversity of them in the stomach.When comparing the healthy with the diseased stomach,there is a change in the composition of the gastric microbiome with increasing abundance of H.pylori(where present)in the gastritis stage,while as the gastric carcinogenesis cascade progresses to gastric cancer,the oral and intestinal-type pathogenic microbial strains predominate.Hp-I creates a premalignant environment of atrophy and intestinal metaplasia and the subsequent alteration in gastric microbiota seems to play a crucial role in gastric tumorigenesis itself.Successful H.pylori eradication is suggested to restore gastric microbiota,at least in primary stages.It is more than clear that Hp-I,gastric microbiota and gastric cancer constitute a challenging tangle and the strong interaction between them makes it difficult to unroll.Future studies are considered of crucial importance to test the complex interaction on the modulation of the gastric microbiota by H.pylori as well as on the relationships between the gastric microbiota and gastric carcinogenesis.展开更多
Gastric cancer represents a common and highly fatal malignancy,and thus a pathophysiology-based reconsideration is necessary,given the absence of efficient therapeutic regimens.In this regard,emerging data reveal a si...Gastric cancer represents a common and highly fatal malignancy,and thus a pathophysiology-based reconsideration is necessary,given the absence of efficient therapeutic regimens.In this regard,emerging data reveal a significant role of autophagy in gastric oncogenesis,progression,metastasis and chemoresistance.Although autophagy comprises a normal primordial process,ensuring cellular homeostasis under energy depletion and stress conditions,alterations at any stage of the complex regulatory system could stimulate a tumorigenic and promoting cascade.Among others,Helicobacter pylori infection induces a variety of signaling molecules modifying autophagy,during acute infection or after chronic autophagy degeneration.Subsequently,defective autophagy allows malignant transformation and upon cancer establishment,an overactive autophagy is stimulated.This overexpressed autophagy provides energy supplies and resistance mechanisms to gastric cancer cells against hosts defenses and anticancer treatment.This review interprets the implicated autophagic pathways in normal cells and in gastric cancer to illuminate the potential preventive,therapeutic and prognostic benefits of understanding and intervening autophagy.展开更多
文摘Helicobacter pylori infection(Hp-I)represents a typical microbial agent intervening in the complex mechanisms of gastric homeostasis by disturbing the balance between the host gastric microbiota and mucosa-related factors,leading to inflammatory changes,dysbiosis and eventually gastric cancer.The normal gastric microbiota shows diversity,with Proteobacteria[Helicobacter pylori(H.pylori)belongs to this family],Firmicutes,Actinobacteria,Bacteroides and Fusobacteria being the most abundant phyla.Most studies indicate that H.pylori has inhibitory effects on the colonization of other bacteria,harboring a lower diversity of them in the stomach.When comparing the healthy with the diseased stomach,there is a change in the composition of the gastric microbiome with increasing abundance of H.pylori(where present)in the gastritis stage,while as the gastric carcinogenesis cascade progresses to gastric cancer,the oral and intestinal-type pathogenic microbial strains predominate.Hp-I creates a premalignant environment of atrophy and intestinal metaplasia and the subsequent alteration in gastric microbiota seems to play a crucial role in gastric tumorigenesis itself.Successful H.pylori eradication is suggested to restore gastric microbiota,at least in primary stages.It is more than clear that Hp-I,gastric microbiota and gastric cancer constitute a challenging tangle and the strong interaction between them makes it difficult to unroll.Future studies are considered of crucial importance to test the complex interaction on the modulation of the gastric microbiota by H.pylori as well as on the relationships between the gastric microbiota and gastric carcinogenesis.
文摘Gastric cancer represents a common and highly fatal malignancy,and thus a pathophysiology-based reconsideration is necessary,given the absence of efficient therapeutic regimens.In this regard,emerging data reveal a significant role of autophagy in gastric oncogenesis,progression,metastasis and chemoresistance.Although autophagy comprises a normal primordial process,ensuring cellular homeostasis under energy depletion and stress conditions,alterations at any stage of the complex regulatory system could stimulate a tumorigenic and promoting cascade.Among others,Helicobacter pylori infection induces a variety of signaling molecules modifying autophagy,during acute infection or after chronic autophagy degeneration.Subsequently,defective autophagy allows malignant transformation and upon cancer establishment,an overactive autophagy is stimulated.This overexpressed autophagy provides energy supplies and resistance mechanisms to gastric cancer cells against hosts defenses and anticancer treatment.This review interprets the implicated autophagic pathways in normal cells and in gastric cancer to illuminate the potential preventive,therapeutic and prognostic benefits of understanding and intervening autophagy.
