Komatsu Keiko, Murata Kohei, Kameyama Masao, Ayaki Masako, Mukai Mutsuko, Ishiguro Shingo, Miyoshi Jun, Tatsuta Masaharu, Inoue Masahiro, Nakamura Hiroyuki
Department of Tumor Biochemistry, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.
Oncology. 2002;63(2):192-200. doi: 10.1159/000063812.
S100A6 and S100A4, two of S100 protein family, have been suggested to be associated with cancer tumorigenesis and metastasis. The aim of this study was to evaluate the expression levels of S100A6 and S100A4 in matched samples of primary human colorectal adenocarcinomas (T), adjacent normal colorectal mucosa (N) and liver metastases (M). This gave us the advantage of directly comparing levels of S100A6 and S100A4 expression within the same genetic background.
In matched samples of N, T and M from 10 colorectal adenocarcinoma patients, expressions of S100A6 and S100A4 were studied by Western blot and immunohistochemical analyses using specific antibodies against each protein.
The expression levels of S100A6 were significantly higher in T than in N (p < 0.05), while those of S100A4 showed no difference between T and N. There were no significant differences in the expression levels of S100A6 or S100A4 between M and T. Similar results were obtained by immunohistochemical analysis. Moreover, S100A6 was stained more intensely in invading fronts than in central portions of both T and M.
The observed differential expression of S100A6 and S100A4 suggests that S100A6, rather than S100A4, is associated with human colorectal adenocarcinoma tumorigenesis and invasion/metastasis.
S100蛋白家族中的两个成员S100A6和S100A4已被认为与癌症的发生和转移有关。本研究的目的是评估S100A6和S100A4在原发性人类结肠腺癌（T）、相邻正常结肠黏膜（N）和肝转移灶（M）的配对样本中的表达水平。这使我们能够在相同遗传背景下直接比较S100A6和S100A4的表达水平。
在10例结肠腺癌患者的N、T和M配对样本中，使用针对每种蛋白质的特异性抗体，通过蛋白质印迹法和免疫组织化学分析研究S100A6和S100A4的表达。
S100A6在T中的表达水平显著高于N（p < 0.05），而S100A4在T和N之间无差异。S100A6或S100A4在M和T之间的表达水平无显著差异。免疫组织化学分析也得到了类似的结果。此外，S100A6在T和M的侵袭前沿比中央部分染色更强烈。
观察到的S100A6和S100A4的差异表达表明，与人类结肠腺癌的发生和侵袭/转移相关的是S100A6，而非S100A4。
