The incidence and mortality of esophageal cancer are high, with strong invasiveness and poor prognosis. In China, the number of morbidity and death accounts for about half of the world. The cause of the disease has not yet been clarified, and it is known to be related to many factors such as chronic damage to the upper digestive tract caused by poor diet and lifestyle, heredity and environment. With the continuous advancement of molecular biology technology, metagenomics and high-throughput sequencing began to be used as non-culture methods instead of traditional culture methods for micro-ecological analysis, and is becoming a research hotspot. Many studies have shown that the disturbance of upper digestive tract microecology may be one of the causes of esophageal cancer, which affects the occurrence and development of esophageal cancer through complex interactions with the body and various mechanisms. This paper reviews the research progress, which is of great significance to further clarify the value of upper gastrointestinal microecology in the pathogenesis, diagnosis and treatment of esophageal cancer.
ObjectiveTo summarize the recent advances in the pathogenic mechanism of microorganisms and pancreatic cancer.MethodThrough the retrieval of relevant literatures, the recent progresses in the study of microorganism and pathogenesis of pancreatic cancer were reviewed.ResultsIn recent years, the potential role of intestinal microbiota in the pathogenic mechanism of pancreatic cancer had been studied. The studies found that the microbiome played an important role in the development of pancreatic cancer. Among them, the infections of Helicobacter pylori, oral pathogenic bacteria such as the Porphyromonas ginggivalis, Aggregatibacter actinomycetemcomitans and Phylum fusobacteria, and the changes of composition and diversity of intestinal microflora were closely related to the pancreatic cancer. The microorganisms induced the chronic inflammation and immune response through multiple pathways. The bacterial lipopolysaccharide stimulated the mutations in the KARS gene and mediated the inflammatory response by activating the nuclear factor-κB signaling pathway through Toll like receptor. The oral pathogenic microorganisms and Helicobacter pylori could also promote the cancer progression by secreting toxins that activated cancer-related signaling pathways.ConclusionsBacteria might be important carcinogens. These microorganisms promote development of cancer by causing chronic inflammation, activating cancer-related pathways, activating immune response, oxidative stress, and damaging DNA double strands.