ARSENIC TRIOXIDE ENHANCES PROLIFERATION OF ESOPHAGEAL CARCINOMA CELLS

Purpose: Arsenic trioxide(As\-2O\-3) has proved to be effective in the treatment of some leukemias and caused apoptosis in leukinua cells and some solid tumor cells. This study focused on the effects of low dosage of As\-2O\-3 on the esophageal carcinoma cells(SHEEC1). Methods: Esophageal carcinoma cells were cultured in flasks and treated with As\-2O\-3 in concentration of 0.1 μmol/L, 0.5 μmol/L and 5.0 μmol/L, respectively. Results: The high dose(5 μmol/L) of As\-2O\-3 induced apoptosis and inhibited proliferation of SHEEC1 cells, and the low doses(0.1μmol/L or 0.5 μmol/L) of As\-2O\-3 enhanced the mitotic index and DNA synthesis(in 0.5 μmol/L), which was determined by quantitative fluorescent cytometry. In transmitted electron microscope(EM), it was showed that SHEEC1 cells treated with As\-2O\-3 in low doses displayed proliferative status with increasing mitochondria and poly ribosomes in cytoplasm and multiple nucleoli in nucleus. Conclusion: The results suggest that As\-2O\-3 in low dosage promotes the proliferation of esophageal carcinoma cells and increament of DNA synthesis. As a conclusion, As\-2O\-3 has the characteristics of mitogenic effects.