Zhang Hao, Wang Yinping, Chen Yue, Sun Suozhu, Li Na, Lv Dongxia, Liu Chuanjun, Huang Lingyun, He Dacheng, Xiao Xueyuan
Key Laboratory for Cell Proliferation and Regulation Biology Ministry of Education, Beijing Normal University, 19th Xinjiekouwai St., 100875 Beijing, China.
Lung Cancer. 2007 Jul;57(1):37-45. doi: 10.1016/j.lungcan.2007.02.020. Epub 2007 Apr 5.
To identify potential markers associated with non-small cell lung cancer (NSCLC) metastasis to brain, comparative proteome analysis on two lung squamous cell carcinoma (SCC) cell lines, NCI-H226 and H226Br (the brain metastatic cell line of NCI-H226), was performed using two-dimensional electrophoresis (2-DE) followed by a tandem mass spectrometer with a matrix-assisted laser desorption/ionization (MALDI) source. Twenty differential proteins were identified, of which 6 proteins were up-regulated in H226Br cell compared with NCI-H226 cells, whereas 14 proteins were down-regulated. S100A7 and 14-3-3sigma, two of candidate proteins significantly upregulated and downregulated in H226Br cell, were selected to verify the liability of the differential proteins by Western blot. The results were in accordance with 2-D data. To determine whether S100A7 overexpression is actually associated with SCC metastasis to brain, S100A7 protein was testified in 10 brain metastasis tissues from NSCLC, 38 primary NSCLC tissues including half matched local positive lymph nodes, 5 primary brain tumors and 2 non-cancer brain tissues by immunohistochemistry. Of particular interest to us was that the positive staining of S100A7 could be found in 3/5 (60%) brain metastases tissue from SCC and 8/21 (38%) the primary lung SCC tissues, while no positive staining was observed in the brain metastases tissue from Ad (n=5), the primary adenocarcinoma (Ad) tissues (n=17), the primary brain tumors (n=5), all local positive lymph nodes from the primary NSCLC (n=19) and non-cancer brain tissues (n=2). These findings suggest that S100A7 expression is closely associated with SCC metastasis to brain and may be a potential biomarker for monitoring the development of SCC.
为了鉴定与非小细胞肺癌（NSCLC）脑转移相关的潜在标志物，使用二维电泳（2-DE），随后采用带有基质辅助激光解吸/电离（MALDI）源的串联质谱仪，对两种肺鳞状细胞癌（SCC）细胞系NCI-H226和H226Br（NCI-H226的脑转移细胞系）进行了比较蛋白质组分析。鉴定出20种差异蛋白，其中6种蛋白在H226Br细胞中相对于NCI-H226细胞上调，而14种蛋白下调。选择在H226Br细胞中显著上调和下调的两种候选蛋白S100A7和14-3-3sigma，通过蛋白质印迹法验证差异蛋白的可靠性。结果与二维电泳数据一致。为了确定S100A7过表达是否真的与SCC脑转移相关，通过免疫组织化学在10例NSCLC脑转移组织、38例原发性NSCLC组织（包括半数匹配的局部阳性淋巴结）、5例原发性脑肿瘤和2例非癌性脑组织中检测了S100A7蛋白。我们特别感兴趣的是，在3/5（60%）的SCC脑转移组织和8/21（38%）的原发性肺SCC组织中可发现S100A7的阳性染色，而在腺癌（Ad）脑转移组织（n = 5）、原发性腺癌（Ad）组织（n = 17）、原发性脑肿瘤（n = 5）、所有原发性NSCLC的局部阳性淋巴结（n = 19）和非癌性脑组织（n = 2）中均未观察到阳性染色。这些发现表明，S100A7表达与SCC脑转移密切相关，可能是监测SCC进展的潜在生物标志物。
