目的研究三氧化二砷对人食管癌细胞株凋亡的诱导作用。方法癌细胞株Ｅ８７１２和ＥＣ１７１贴壁生长，在电镜观察的基础上，用碘化丙啶（ＰＩ）染色和ＴＵＮＥＬ将凋亡细胞反映在流式细胞仪（ＦＣＭ）上。结果经三氧化二砷２μｍｏｌ／Ｌ作用后，电镜下见部分细胞核染色质凝聚，呈半月形；ＦＣＭ细胞ＤＮＡ检得亚Ｇ１细胞峰；部分Ｇ１期细胞ＴＵＮＥＬ标记呈阳性。结论结果表明，三氧化二砷能诱人食管癌细胞株的凋亡，此药对食管癌等实体瘤的治疗有诱入的应用前景。同时表明，ＦＣＭ具有敏感、特异性强及定量等优点 Objective To study the induction of arsenic trioxide on the apoptosis of human esophageal cancer cell lines. METHODS: E8712 and EC171 cells were adherently grown on the basis of electron microscopy. Apoptotic cells were stained with propidium iodide (PI) and TUNEL on flow cytometer (FCM). Results After treated with arsenic trioxide (2μmol/L), some nuclear chromatin condensed under the electron microscope and showed a half-moon shape. FCM cell DNA detected sub-G1 cell peaks; some G1 cells showed positive TUNEL labeling. Conclusion The results show that arsenic trioxide can induce apoptosis in esophageal cancer cell lines, and this drug has a lucrative application prospect for the treatment of solid tumors such as esophageal cancer. It also shows that FCM has the advantages of sensitivity, specificity, and quantitative