癌症每年吞噬约 6 0 0 0万人的生命[1] ,是人类的主要杀手之一。近几十年来 ,尤其是美国在 1 971年提出“对癌症宣战”以来 ,人们已经对癌症发生、发展的机制以及治疗癌症的方法进行了大量研究 ,并且取得了许多成果。现在人们普遍接受的观点认为 :癌症的发生是由于细胞不受控制 Cancer, which engulfs about 60 million lives a year [1], is one of the major human killers. In recent decades, especially since the United States proposed the “declaration of war on cancer” in 1971, a great deal of research has been carried out on the mechanism of cancer occurrence and development and on the treatment of cancer and many achievements have been made. It is now generally accepted that cancer occurs because cells are out of control