Experimental Studies On The Effects Of Sterigmatocystin On Esophageal Cells

Objectives: Sterigmatocystin(ST) is one of predominant contamination mycotoxins in foodstuffs and grains of high-risks areas of cancer of esophagus in China. Our preliminary work showed that liquid in pickled vegetables consumed by residents of Taihang Mountain area in Hebei Province and corn flours inoculated with ST could induce lung adenocarcinoma and dysplasia of glandular stomach. No evident changes were found in esophageal mucosa. There was no enough evidence to prove that ST was one of etiological factors of esophageal carcinoma.The immune function was one of major factors which affected the development of carcinoma. And the monitoring function of immune system was negative in carcinogenesis for a lot of reasons. Our preliminary work showed that ST can induce apoptosis of human peripheral blood lymphocytes (HPBLs) in vitro and significant time-effect correlation could be found from 1 to 48 hrs of ST treatment and a significant concentration-effect correlation could be found from 0.125 to 2.0 mg/L in ST concentration, thus the results suggested ST may have some negative effects on human immunosystem. In another experiment, we found that within the concentration range from 0.125mg/L to 2.0mg /L, ST could inhibit the expression of HLA-â… of HPBMc in vitro dose-dependently.It was found that the expression of HLA-â… of esophageal carcinoma in high-risks areas of esophageal cancer in China were lower than that of normal tissues. A positive correlation was demonstrated between HLA-â… expression and the histological grade of cancer as well as lymph node metastasis.To further explore the possible immunological effects of ST on the carcinogensis of esophageal carcinoma, the following experiments were...