Pathogenetic effects of salted pork in an area of China with high-risk for stomach cancer.

Abstract

To study the pathogenetic effects of salted pork (SP) (a special food in Zhuanghe City, a region of northern China that is a high-risk area for stomach cancer) on stomach cancer, and a provide scientific basis for the primary prevention of stomach cancer in this high-risk region. This study consisted of three distinct parts. The first part involved a study of SP mutagenicity and employed both the Ames test and micronuclei assay using V79 cells. The second part included a study of SP's effect on the gastric mucosa of residents in the Zhuanghe area who had consumed SP for more than ten years. Additionally, these studies involved an analysis of the dose effect relationship between SP and pathological changes in gastric mucosa, with a total of 300 cases analyzed. The third part of this study involved an observation of the mucosal lesions from experimental dogs by both gastroscopy and mucosal biopsy. Six healthy male dogs were selected, three were fed with SP, and the others served as controls. This study revealed that SP extract could mutate Salmonella typhimurium TA98 and induce an increase in both the micro nuclei rate (MNR) and micro nuclei cell rate (MNCR) of V79 at a dose range of 20-80 μL/mL. There were significant dose-effect relations between SP and either MNR or MNCR. Pathological changes in the gastric mucosa of local residents who had consumed SP were significantly different from those of the control group. In people who had consumed SP for ten years, mucosal lesions were found that contained evidence of necrosis and erosion; In those who consumed SP for ten-20 years, both hyperplasia and dysplasia were seen in addition to the above lesions. In individuals who had consumed SP for 20-30 years, severe dysplasia and malignant changes were found. Furthermore, SP had damaging effect on the gastric mucosa of dogs that were fed SP. The mucosal lesions became more severe with increased feeding time. SP is a strong mutagen and long-term SP exposure may result in repeated gastric mucosal damage and repair, ultimately leading to severe dysplasia and malignancy.