Shen Zhong-Ying, Xu Li-Yan, Li En-Min, Cai Wei-Jia, Shen Jian, Chen Ming-Hua, Cen Shan, Tsao Sai-Wah, Zeng Yi
Department of Pathology, Medicine College of Shantou University, Shantou 515031, PR China.
Oncol Rep. 2004 Mar;11(3):647-54.
To investigate the multistage process of carcinogenesis, the progressive alteration of the morphology, telomerase, cytogenesis, oncogenes and tumorigenicity in the process of immortalization and malignant transformation of the human fetal esophageal epithelial cell (SHEE) was studied. The SHEE cells were immortalized by gene E6E7 of human papilloma virus (HPV) type 18 in our laboratory and continually cultivated over 100 passages, which had been malignantly transformed. Cells at the 11th, 35th, 65th and 100th passage were examined according to the following criteria: morphological changes of cell growth, contact-inhibition and anchorage-independent growth (AIG); the cell proliferative and apoptotic index; the modal number of chromosomes; c-myc, p53, bcl-2, ras; telomere length and activities of telomerase and tumorigenicity in nude mice or severe combined immunodeficient (SCID) mice. The cells of the 11th passage were well differentiated and the cells of 100th passage were relatively poorly differentiated with polymorphism, while the cells of 35th and 65th had two distinct differentiations. The proliferative indexes were 21.1%, 32.5%, 33.2%, and 40.9% and the apoptotic indexes were 3.3%, 2.7%, 3.5%, 2.7% in the 11th, 35th, 65th and 100th passage respectively. Karyotypes of four cell passages belonged to hyperdiploidy and hypotriploidy. C-myc, ras, p53 genes were low in the 10th and 35th, and high in the 65th and 100th passage, but bcl-2 was low in 4 passages. Telomere length sharply decreased from normal fetal esophagus cells until the 35th passage, but it was stably expressed in the 65th and 100th passage. The activities of telomerase were expressed in cells of the 35th, 65th and 100th passages. The efficiency of AIG varied in different passages of the SHEE cell and was absent in the 11th passage, low efficiency in the 35th passage and 65th passage, and high efficiency in the 100th passage. Transplanted cells of the 65th and 100th passage into SCID mice resulted in tumor formation, but only the 100th passage cells could grow in nude mice. All of these characteristic changes were in dynamic progressive process. These data demonstrate that carcinogenesis of esophageal epithelial cells induced by HPV is the multistage process, which goes through the initial, immortal, premalignant and malignant transformation stages. The generation of esophageal carcinoma is caused by the accumulation of cellular, genetic and molecular changes.
为研究癌变的多阶段过程，对人胎儿食管上皮细胞（SHEE）永生化及恶性转化过程中形态、端粒酶、细胞发生、癌基因及致瘤性的渐进性改变进行了研究。本实验室用人乳头瘤病毒18型（HPV）的E6E7基因使SHEE细胞永生化，并连续传代培养100代以上，这些细胞已发生恶性转化。根据以下标准对第11、35、65和100代细胞进行检测：细胞生长的形态变化、接触抑制和非锚定依赖性生长（AIG）；细胞增殖和凋亡指数；染色体众数；c-myc、p53、bcl-2、ras；端粒长度及端粒酶活性以及在裸鼠或严重联合免疫缺陷（SCID）小鼠中的致瘤性。第11代细胞分化良好，第100代细胞分化相对较差，具有多态性，而第35和65代细胞有两种不同的分化情况。第11、35、65和100代细胞的增殖指数分别为21.1%、32.5%、33.2%和40.9%，凋亡指数分别为3.3%、2.7%、3.5%、2.7%。四代细胞的核型均属于超二倍体和亚三倍体。c-myc、ras、p53基因在第10和35代时低表达，在第65和100代时高表达，但bcl-2在四代细胞中均低表达。端粒长度从正常胎儿食管细胞到第35代急剧下降，但在第65和100代时稳定表达。端粒酶活性在第35、65和100代细胞中表达。SHEE细胞不同传代的AIG效率不同，第11代细胞无AIG，第35和65代效率低，第100代效率高。将第65和100代细胞移植到SCID小鼠中可形成肿瘤，但只有第100代细胞能在裸鼠中生长。所有这些特征性变化都处于动态渐进过程中。这些数据表明，HPV诱导的食管上皮细胞癌变是一个多阶段过程，经历了初始、永生化、癌前和恶性转化阶段。食管癌的发生是细胞、遗传和分子变化积累的结果。
