Modern Correa pathway of intestinal-type gastric carcinogenesis, with risk factors and host mechanisms in green, molecular genetics in blue, and preventive factors in yellow. As histological changes progress, antioxidant systems and DNA repair mechanisms become less effective and the epigenetic effects of Helicobacter pylori infection and environmental carcinogens more difficult to reverse. AA: ascorbic acid; BMD: bone marrow derived; cdx: caudal type homeobox gene; c-erbB: human epidermal growth factor oncogene; CDH1: E-cadherin gene; GSH: glutathione; HPE: Helicobacter pylori eradication, LOH: loss of heterozygosity; SPEM: spasmolytic polypeptide-expressing metaplasia; TET1: ten eleven translocation methylcytosine dioxygenase 1 [6,19,26].