Lim Wonbong, Kim Hye-Eun, Kim Young, Na Risu, Li Xiaojie, Jeon Sangmi, Choi Hongran, Kim Okjoon
Department of Premedical Science, College of Medicine, Chosun University, Dong-Gu, Gwangju, Republic of Korea.
Department of Oral Pathology, Dental Science Research Institute and Medical Research Center for Biomineralization Disorders, School of Dentistry, Chonnam National University, Bug-Gu, Gwangju, Republic of Korea.
Int J Oncol. 2016 Sep;49(3):991-1000. doi: 10.3892/ijo.2016.3582. Epub 2016 Jun 16.
One of the theories on cancer stem cells (CSCs) states that these cells initiate most tumors and give rise to more-or-less differentiated tumor cells. Genetic signatures of CSCs are thought to predict tumor recurrence and metastases, thus, supporting the notion that CSCs may be metastatic precursors and induce epithelial-to-mesenchymal transition (EMT). In this study, we tried to examine the association between CSCs and EMT (using specific markers) in the mucoepidermoid carcinoma cell line YD15 and its derivative cell line YD15M (lymph node metastasis). Relative protein expression levels were analyzed by western blotting, flow cytometry, and immunofluorescence assays. In addition, cell cycle assay and aldehyde dehydrogenase (ALDH) activity assay were carried out. Under growth conditions, YD15M cells formed irregular spherical colonies consistent with a stem cell phenotype. YD15M cells demonstrated the low expression of E-cadherin and β-catenin but high expression of vimentin than that in YD15 cells. In the metastatic cells (YD15M), the coexpression of vimentin and CD133 was detected. Weak proliferation based on cell cycle analysis and decreased PCNA expression was also observed. In addition, expression levels of ALDHA1, OCT4, and NANOG (CSC-like properties) were significantly increased in YD15M cells. Taken together, these findings should help to elucidate the interplay between EMT and CSC-like properties during metastasis and may provide useful information for the development of a novel classification system and therapeutic strategies against head and neck cancer.
癌症干细胞（CSCs）的一种理论认为，这些细胞引发了大多数肿瘤，并产生或多或少分化的肿瘤细胞。CSCs的基因特征被认为可以预测肿瘤复发和转移，因此，支持了CSCs可能是转移前体并诱导上皮-间质转化（EMT）的观点。在本研究中，我们试图研究黏液表皮样癌细胞系YD15及其衍生细胞系YD15M（淋巴结转移）中CSCs与EMT之间的关联（使用特定标志物）。通过蛋白质印迹、流式细胞术和免疫荧光分析来分析相关蛋白表达水平。此外，还进行了细胞周期分析和醛脱氢酶（ALDH）活性分析。在生长条件下，YD15M细胞形成不规则球形集落，与干细胞表型一致。与YD15细胞相比，YD15M细胞中E-钙黏蛋白和β-连环蛋白表达低，但波形蛋白表达高。在转移细胞（YD15M）中，检测到波形蛋白和CD133的共表达。基于细胞周期分析还观察到增殖较弱以及增殖细胞核抗原（PCNA）表达降低。此外，YD15M细胞中ALDHA1、OCT4和NANOG（CSC样特性）的表达水平显著升高。综上所述，这些发现有助于阐明转移过程中EMT与CSC样特性之间的相互作用，并可能为开发针对头颈癌的新型分类系统和治疗策略提供有用信息。
