An in vitro multistep carcinogenesis model for both HPV-positive and -negative human oral squamous cell carcinomas.
An in vitro multistep carcinogenesis model for both HPV-positive and -negative human oral squamous cell carcinomas.
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DOI：
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发表时间：
2011
影响因子：
5.3
通讯作者：
Yusuke Zushi;M. Narisawa‐Saito;K. Noguchi;Yuki Yoshimatsu;T. Yugawa;Nagayasu Egawa;M. Fujita;M. Urade;T. Kiyono
中科院分区：
文献类型：
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作者：
Yusuke Zushi;M. Narisawa‐Saito;K. Noguchi;Yuki Yoshimatsu;T. Yugawa;Nagayasu Egawa;M. Fujita;M. Urade;T. Kiyono
口腔鳞状细胞癌（OSCC）被认为源自人类口腔角质形成细胞。在大约 25% 的 OSCC 中检测到了人乳头瘤病毒 (HPV)（主要是 16 型和 18 型）的 DNA，它们是宫颈癌的病原体。根据 E6 和 E7 分别在 p53 和 pRB 失活中的既定作用，在 HPV 阴性 OSCC 中经常观察到 p53 突变和 p16(INK4a) 失活。此外，在 HPV 阳性和阴性 OSCC 中经常观察到其他改变，例如表皮生长因子受体 (EGFR) 的过度表达。然而，这些异常的积累与多步骤致癌之间的因果关系尚不完全清楚。为了阐明潜在的过程，我们将 HPV16 E6/E7 或突变型 CDK4 (CDK4(R24C))、细胞周期蛋白 D1 和人端粒酶逆转录酶 (TERT) 转导到原代人舌角质形成细胞 (HTK) 中，并获得永生细胞群 HTK-16E6E7 和 HTK-K4DT。将致癌性 HRAS 或 EGFR 与 MYC 一起转导至 HTK-16E6E7 和表达 HTK-K4DT 的显性失活 p53 中，导致裸鼠中不依赖锚定的生长和皮下肿瘤形成。这些结果表明，在 pRB 和 p53 途径失活以及端粒酶激活的背景下，HRAS 突变或 EGFR 激活与 MYC 过表达相结合，在 HTK 转化中发挥着关键作用。这种概括 OSCC 发育的体外模型系统应有助于进一步研究口腔癌变机制。
Oral squamous cell carcinomas (OSCCs) are considered to arise from human oral keratinocytes. DNAs of human papillomaviruses (HPVs), predominantly types 16 and 18, etiological agents of cervical cancer, have been detected in approximately 25% of OSCCs. In accordance with the established role of E6 and E7 in inactivating p53 and pRB, respectively, mutations of p53 and inactivation of p16(INK4a) are frequently observed in HPV-negative OSCCs. In addition, other alterations such as overexpression of epidermal growth factor receptor (EGFR) are often observed in both HPV-positive and -negative OSCCs. However, causal-relationships between accumulation of these abnormalities and multi-step carcinogenesis are not fully understood. To elucidate underlying processes, we transduced either HPV16 E6/E7 or mutant CDK4 (CDK4(R24C)), cyclin D1 and human telomerase reverse transcriptase (TERT) into primary human tongue keratinocytes (HTK), and obtained immortal cell populations, HTK-16E6E7 and HTK-K4DT. Additional transduction of oncogenic HRAS or EGFR together with MYC into the HTK-16E6E7 and dominant-negative p53 expressing HTK-K4DT resulted in anchorage-independent growth and subcutaneous tumor formation in nude mice. These results indicate that either HRAS mutation or activation of EGFR in cooperation with MYC overexpression play critical roles in transformation of HTKs on a background of inactivation of the pRB and p53 pathways and telomerase activation. This in vitro model system recapitulating the development of OSCCs should facilitate further studies of mechanisms of carcinogenesis in the oral cavity.