图1细胞周期示意图细胞的增殖、分化与凋亡正常细胞的生存、增殖、分化等功能如失去适当的调节,就有可能导致表型改变和肿瘤发生。肿瘤细胞的不适当调节有四个方面:①细胞增殖的正常制约机制松散。②分化紊乱,肿瘤细胞可能在分化的某个阶段被阻滞,或分化成不适当的或异常的细胞 Figure 1 cell cycle diagram of cell proliferation, differentiation and apoptosis normal cell survival, proliferation, differentiation and other functions such as the loss of proper regulation, it may lead to phenotypic changes and tumorigenesis. Inappropriate regulation of tumor cells in four areas: ① normal cell proliferation control mechanism loose. ② differentiation disorders, tumor cells may be at a certain stage of differentiation is blocked, or differentiated into inappropriate or abnormal cells