Department of Oral and Maxillofacial Surgery, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai, China.
Oral Oncol. 2011 Aug;47(8):693-7. doi: 10.1016/j.oraloncology.2011.06.003. Epub 2011 Jun 25.
In our previous study, we established an in vitro cellular carcinogenesis model of oral squamous cell carcinoma (OSCC), including a human immortalized oral epithelial cell (HIOEC) and a cancerous cell line (HB96). Microarray analysis showed that the gene encoding Yes-associated protein (YAP) was significantly increased in HB96 cells compared with HIOEC cells. But the underlying mechanism of YAP on oncogenesis, especially its downstream targets, are still not clear. YAP expression in OSCC cell lines and tissue specimens were investigated by using real-time PCR, western blotting and immunohistochemistry staining. YAP put-back plasmid with four mutation sites after YAP-siRNA interference was constructed by site-directed mutagenesis. Cell growth and colony formation were observed after YAP-siRNA interference or YAP put-back again in CAL27 cells. YAP expression was increased in the cellular carcinogenesis models and the clinical samples from primary OSCC patients. Inhibition of YAP by siRNA interference in CAL27 cells significantly inhibited cell proliferation and colony formation in soft agar, but these abilities were rescued when YAP was put-back again. At the same time, Fos Related Activator-1 (Fra-1) was down-regulated when YAP was inhibited by siRNA interference while Fra-1 was rescued when YAP was put-back again. Immunohistochemistry results also indicated that higher levels of YAP were significantly associated with Fra-1 overexpression in OSCC clinical samples. YAP could promote cell proliferation by activating transcription factor Fra-1 in oral squamous cell carcinoma.
在我们之前的研究中，我们建立了一个口腔鳞状细胞癌（OSCC）的体外细胞癌变模型，包括一个人永生化口腔上皮细胞（HIOEC）和一个癌细胞系（HB96）。微阵列分析显示，与 HIOEC 细胞相比，HB96 细胞中编码 Yes 相关蛋白（YAP）的基因显著增加。但是，YAP 在致癌作用中的潜在机制，尤其是其下游靶标，仍然不清楚。通过实时 PCR、western blot 和免疫组织化学染色研究了 OSCC 细胞系和组织标本中的 YAP 表达。通过定点诱变构建了 YAP-siRNA 干扰后具有四个突变位点的 YAP 回补质粒。在 CAL27 细胞中进行 YAP-siRNA 干扰或再次回补 YAP 后，观察细胞生长和集落形成。在细胞癌变模型和原发性 OSCC 患者的临床样本中，YAP 表达增加。在 CAL27 细胞中抑制 YAP 通过 siRNA 干扰显著抑制软琼脂中的细胞增殖和集落形成，但当再次回补 YAP 时，这些能力得到挽救。同时，当 YAP 被 siRNA 干扰抑制时，Fos 相关激活物-1（Fra-1）下调，而当 YAP 再次回补时，Fra-1 被挽救。免疫组织化学结果还表明，在 OSCC 临床样本中，YAP 水平较高与 Fra-1 过表达显著相关。YAP 可通过激活转录因子 Fra-1 在口腔鳞状细胞癌中促进细胞增殖。
