| 1 | Helicobacter pylori-induced inflammation and epigenetic changes during gastric carcinogenesis显示文摘The sequence of events associated with the development of gastric cancer has been described as 'the gastric precancerous cascade'. This cascade is a dynamic process that includes lesions, such as atrophic gastritis, intestinal metaplasia and dysplasia. According to this model, Helicobacter pylori(H. pylori) infection targets the normal gastric mucosa causing non-atrophic gastritis, an initiating lesion that can be cured by clearing H. pylori with antibiotics or that may then linger in the case of chronic infection and progress to atrophic gastritis. The presence of virulence factors in the infecting H. pylori drives the carcinogenesis process. Independent epidemiological and animal studies have confirmed the sequential progression of these precancerous lesions. Particularly long-term follow-up studies estimated a risk of 0.1% for atrophic gastritis/intestinal metaplasia and 6% in case of dysplasia for the long-term development of gastric cancer. With this in mind, a better understanding of the genetic and epigenetic changes associated with progression of the cascade is critical in determining the risk of gastric cancer associated with H. pylori infection. In this review, we will summarize some of the mostrelevant mechanisms and focus predominantly but not exclusively on the discussion of gene promoter methylation and mi RNAs in this context. | Manuel A Valenzuela Jimena Canales Alejandro H Corvalán Andrew FG Quest | 2015 | World Journal of Gastroenterology2015,21,45: | 33 |
| 2 | Dysregulation of non-coding RNAs in gastric cancer显示文摘Gastric cancer(GC) is one of the most common cancers in the world and a significant threat to the health of patients, especially those from China and Japan. The prognosis for patients with late stage GC receiving the standard of care treatment, including surgery, chemotherapy and radiotherapy, remains poor. Developing novel treatment strategies, identifying new molecules for targeted therapy, and devising screening techniques to detect this cancer in its early stages are needed for GC patients. The discovery of non-coding RNAs(nc RNAs), primarily micro RNAs(mi RNAs) and long non-coding RNAs(lnc RNAs), helped to elucidate the mechanisms of tumorigenesis, diagnosis and treatment of GC. Recently, significant research has been conducted on non-coding RNAs and how the regulatory dysfunction of these RNAs impacts the tumorigenesis of GC. In this study, we review papers published in the last five years concerning the dysregulation of noncoding RNAs, especially mi RNAs and lnc RNAs, in GC. We summarize instances of aberrant expression of the ncR NAs in GC and their effect on survival-related events, including cell cycle regulation, AKT signaling, apoptosis and drug resistance. Additionally, we evaluate how nc RNA dysregulation affects the metastatic process, including the epithelial-mesenchymal transition, stem cells, transcription factor activity, and oncogene and tumor suppressor expression. Lastly, we determine how ncR NAs affect angiogenesis in the microenvironment of GC. We further discuss the use of ncR NAs as potential biomarkers for use in clinical screening, early diagnosis and prognosis of GC. At present, no ideal ncR NAs have been identified as targets for the treatment of GC. | Qing Yang Ren-Wen Zhang Peng-Cheng Sui Hai-Tao He Lei Ding | 2015 | World Journal of Gastroenterology2015,21,39: | 1 |