传统发育生物学理论认为,肿瘤是由成熟细胞突变而来,每个肿瘤细胞都有相同、无限增值、分化和成瘤的能力。最近研究发现,肿瘤生长是肿瘤组织中极少量具无限增殖潜能的肿瘤干细胞(tumor stem cell)增殖的结果。越来越多的证据表明,肿瘤内存在类似正常干细胞的具自我更新能力的肿 The theory of traditional developmental biology holds that tumors are mutated from mature cells, and each tumor cell has the same, infinitely-advanced, differentiated, and tumor-forming ability. Recent studies have found that tumor growth is the result of proliferation of tumor stem cells that have a very small number of immortalizing potentials in tumor tissues. More and more evidence shows that tumors have self-renewal ability similar to normal stem cells