中文摘要：

芳香化酶抑制剂（ aromatase inhibitors，AIs）在绝经后雌激素依赖性乳腺癌的治疗中取得了令人鼓舞的疗效。大型的临床试验ATAC和BIG 1-98均证明第三代芳香化酶抑制剂作为绝经后乳腺癌的辅助治疗可明显提高患者的无病生存期，疗效优于他莫昔芬。随着AIs在临床广泛应用及用药时间的延长，AIs耐药也成了临床医生不可回避的问题，至今国内尚没有对AIs耐药分子机制的详细报道，本文通过对国内外一些实验室和临床研究结果的综述，拟概述乳腺癌AIs耐药分子机制的研究进展。

英文摘要：

The third-generation aromatase inhibitors（ AIs）are now successfully used as first-line drugs in the endocrine treatment of estrogen-dependent breast cancer in postmenopausal patients. Clinical trials have demonstra-ted the importance of AI therapy in the effective treatment of hormone-dependent breast cancer. Yet,as with all prolonged drug therapy,resistance to aromatase inhibitors does develop. To date,the precise mechanism responsible for resistance to AIs is not completely understood. In this paper,several mechanisms are discussed.