论文部分内容阅读
癌细胞是由正常细胞变化而来。一个人体内有数十兆个细胞,其中约1/3的细胞有变成癌细胞的可能性。癌细胞由正常细胞发生癌变的机理是正常体细胞遗传基因发生了变化。一个细胞中有数以万计的基因,其中可能有数十个是致癌基因和抑癌基因,这些基因大多数结构和产生蛋白质的结构机能都已搞清,包括细胞生长因子及其受体、参与信息传递的因子,蛋白磷酸化酶、DNA 信息翻译、参与复制 DNA 的蛋白质,甚至细胞分裂的调整等。由于这些基因的变化,使致癌基因活化,抑癌基因灭活。这些基因变化包括基因突变、基因重组、基因放大、基因缺损等。大多数人类的癌中,这样的基因变化合并发生。在结肠癌、肺癌等,正常细胞中有十个左右的基因发生变化,最早转变成恶性肿瘤细胞。
Cancer cells are changed from normal cells. There are dozens of trillions of cells in a person’s body, and about one-third of them have the possibility of becoming cancerous cells. The mechanism by which normal cancer cells undergo canceration is the change in normal somatic genes. There are tens of thousands of genes in a cell. Among them, there may be dozens of oncogenes and tumor suppressor genes. Most of these genes have structural and structural mechanisms for protein production, including cell growth factors and their receptors. Information transfer factors, protein phosphorylase, translation of DNA information, proteins involved in DNA replication, and even cell division adjustments. As a result of these gene changes, oncogenes are activated and tumor suppressor genes are inactivated. These genetic changes include gene mutations, gene recombination, gene amplification, gene deletion, and the like. In most human cancers, such genetic changes occur in combination. In colon cancer, lung cancer, and so on, about ten genes in normal cells have changed, and they have initially turned into malignant cells.