Effects of a regional Chinese diet on proliferation of human esophageal cancer cell line Eca-109 by a sero-physiology method.

Esophageal squamous cell carcinoma (ESCC) is prevalent in Yanting (YT) country located in southwestern China. Residents in the YT region have an unusual diet pattern and the role of the YT diet on the risk of ESCC is still uncertain. The present study was to examine the possible effects of sera from rats fed with the YT diet on proliferation of human esophageal cancer cell line Eca-109 by means of a sero-physiology approach. Firstly, two feasibilities were assessed to set up the sero-physiology method. We found that rats fed with a human adult diet in Chengdu region (ESCC-low-risk-area) for 30d had very close body weight gains in comparison with the control rats fed with the conventional diet, confirming the feasibility of feeding rats with a human diet without affecting their normal growth. Cell growth results showed that 5% non-deactivated rat serum had exactly the same effect on the proliferation of Eca-109 cells compared with the fetal bovine sera (FBS) control, confirming the feasibility of cultivating Eca-109 cells with the rat serum instead of FBS. Subsequently, cell proliferation results indicated that rats' sera fed with the YT diet significantly promoted Eca-109 cells proliferation but inhibited human normal liver epithelial cell line control HL7702 proliferation, whereas rats' sera fed with the Chengdu diet didn't have these effects on the two cell lines. The different effects of the two human diets on proliferation of Eca-109 cells demonstrated that the sero-physiology method is effective in studying the relationship between diet and cancer, and there maybe exist cancer-promoting factors in the YT diet.