Creation of tumorigenic human endometrial epithelial cells with intact chromosomes by introducing defined genetic elements
Creation of tumorigenic human endometrial epithelial cells with intact chromosomes by introducing defined genetic elements
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DOI：
10.1038/sj.onc.1209575
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发表时间：
2006-09-14
期刊：
影响因子：
8
通讯作者：
Kiyono, T.
中科院分区：
文献类型：
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作者：
Mizumoto, Y.;Kyo, S.;Kiyono, T.
在人类子宫内膜癌中已经发现了几种基因突变，但形成子宫内膜癌细胞所需的特定突变组合仍然未知。在本研究中，我们建立了一个子宫内膜癌发生的体外模型，在该模型中，将定义的遗传元件引入子宫内膜上皮细胞中，以创建不同阶段的转化子宫内膜细胞。将人乳头瘤病毒16型E6/E7基因和人端粒酶逆转录酶（hTERT）基因导入人原代子宫内膜上皮细胞中足以产生永生化细胞。在早期传代中引入hTERT稳定端粒并产生具有正常核型的永生化细胞，而在后期传代中引入hTERT产生永生化细胞但具有广泛的染色体异常。然而，这两种永生化细胞系均未表现出致瘤表型。通过将突变的K-ras等位基因引入永生化细胞中，保持其染色体完整，从而产生具有侵袭能力的致瘤性子宫内膜上皮细胞。抑制PTEN基因和激活Akt通路并没有产生致瘤表型，尽管后者赋予了锚定非依赖性生长能力。这些研究结果表明，肿瘤转化的人子宫内膜细胞可以发生在没有广泛的染色体异常，Rb失活，端粒酶激活和改变K-ras信号的组合是足够的体外肿瘤转化。本实验模型有助于阐明子宫内膜癌发生的遗传要求，并有助于检测和开发特定致癌途径的特异性抑制剂。
Several genetic mutations have been identified in human endometrial cancers, but the specific combinations of mutations required to form endometrial cancer cells remain unknown. In the present study, we established an in vitro model of endometrial carcinogenesis, in which defined genetic elements were introduced into endometrial epithelial cells to create transformed endometrial cells at different stages. Introduction of the human papillomavirus type 16 E6/E7 gene and the human telomerase reverse transcriptase (hTERT) gene into human primary endometrial epithelial cells was sufficient to generate immortalized cells. Introduction of hTERT in early passages stabilized telomeres and created immortalized cells with normal karyotype, whereas introduction of hTERT in later passages generated immortalized cells but with widespread chromosome abnormalities. However, neither of those two immortalized cell lines exhibited tumorigenic phenotypes. Tumorigenic endometrial epithelial cells with invasive capacity were created by introducing a mutant K-ras allele into immortalized cells, keeping their chromosomes intact. Inhibiting the PTEN gene and activating Akt pathways did not create tumorigenic phenotypes, although the latter conferred anchorage-independent growth capacity. These findings suggest that neoplastic transformation of human endometrial cells can occur in the absence of widespread chromosomal abnormality, and that the combination of Rb inactivation, telomerase activation and altered K-ras signaling is sufficient for in vitro neoplastic transformation. The present experimental model can help clarify the genetic requirements for endometrial carcinogenesis, and it is useful for testing and developing specific inhibitors of specific oncogenic pathways.