Key Laboratory of Radiation Biology, School of Radiation Medicine and Protection, Medical College of Soochow University, Suzhou, China.
Acta Pharmacol Sin. 2012 Feb;33(2):250-60. doi: 10.1038/aps.2011.163. Epub 2011 Dec 12.
To investigate the effects of the transducer of ErbB-2.1 (TOB1) on the proliferation, migration and invasion of human lung cancer cells in vitro.
Human lung cancer cell lines (95-D, A549, NCI-H1299, NCI-H1975, NCI-H661, NCI-H446, NCI-H1395, and Calu-3) and the normal human bronchial epithelial (HBE) cell line were tested. The expression levels of TOB1 in the cells were determined with Western blot and RT-PCR analyses. TOB1-overexpressing cell line 95-D/TOB1 was constructed using lipofectamine-induced TOB1 recombinant plasmid transfection and selective G418 cell culture. The A549 cells were transcend-transfected with TOB1-siRNA. MTT assay, flow cytometry and Western blot analysis were used to examine the effects of TOB1 on cancer cell proliferation and wound healing. Transwell invasive assay was performed to evaluate the effects of TOB1 on cancer cell migration and invasion. The activity of MMP2 and MMP9 was measured using gelatin zymography assay.
The expression levels of TOB1 in the 8 human lung cancer cell lines were significantly lower than that in HBE cells. TOB1 overexpression inhibited the proliferation of 95-D cells, whereas TOB1 knockdown with TOB1-siRNA promoted the growth of A549 cells. Decreased cell migration and invasion were detected in 95-D/TOB1 cells, and the suppression of TOB1 enhanced the metastasis in A549 cells. TOB1 overexpression not only increased the expression of the phosphatase and tensin homolog (PTEN), an important tumor suppressor, but also regulated the downstream effectors in the PI3K/PTEN signaling pathway, including Akt, ERK1/2, etc. In contrast, decreased expression of TOB1 oppositely regulated the expression of these factors. TOB1 also regulates the gelatinase activity of MMP2 and MMP9 in lung cancer cells.
The results demonstrate that the PI3K/PTEN pathway, which is essential for carcinogenesis, angiogenesis, and metastasis, may be one of the possible signaling pathways for regulation of proliferation and metastasis of human lung cancer cells by TOB1 in vitro.
研究 ErbB-2.1 转导物（TOB1）对体外人肺癌细胞增殖、迁移和侵袭的影响。
检测人肺癌细胞系（95-D、A549、NCI-H1299、NCI-H1975、NCI-H661、NCI-H446、NCI-H1395 和 Calu-3）和正常人类支气管上皮（HBE）细胞系中 TOB1 的表达水平。Western blot 和 RT-PCR 分析检测细胞中 TOB1 的表达水平。采用脂质体转染 TOB1 重组质粒和选择性 G418 细胞培养构建 TOB1 过表达细胞系 95-D/TOB1。用 TOB1-siRNA 转染 A549 细胞。MTT 法、流式细胞术和 Western blot 分析检测 TOB1 对癌细胞增殖和伤口愈合的影响。Transwell 侵袭试验评估 TOB1 对癌细胞迁移和侵袭的影响。明胶酶谱法测定 MMP2 和 MMP9 的活性。
8 个人肺癌细胞系中 TOB1 的表达水平明显低于 HBE 细胞。TOB1 过表达抑制 95-D 细胞的增殖，而用 TOB1-siRNA 敲低 TOB1 促进 A549 细胞的生长。95-D/TOB1 细胞的迁移和侵袭能力下降，TOB1 的抑制增强了 A549 细胞的转移。TOB1 过表达不仅增加了重要的肿瘤抑制因子磷酸酶和张力蛋白同源物（PTEN）的表达，还调节了 PI3K/PTEN 信号通路的下游效应物，包括 Akt、ERK1/2 等。相反，TOB1 表达下调则调节这些因子的表达。TOB1 还调节肺癌细胞中 MMP2 和 MMP9 的明胶酶活性。
结果表明，PI3K/PTEN 通路是致癌、血管生成和转移所必需的通路之一，可能是 TOB1 体外调节人肺癌细胞增殖和转移的信号通路之一。
