Kiemer A K, Takeuchi K, Quinlan M P
Department of Pharmacy, Center of Drug Research, University of Munich, Butenandtstr. 5-13, 81377 Munich, Germany.
Oncogene. 2001 Oct 11;20(46):6679-88. doi: 10.1038/sj.onc.1204872.
The adenovirus E1A12S gene product (WT12S) immortalizes epithelial cells and they retain their differentiated characteristics, but certain mutants cannot do the latter. Characterization of mutant immortalized epithelial cells indicated that they had undergone epithelial mesenchymal transition (EMT). Coexpression of V12ras with WT12S leads to benign tumors, but to malignant tumors with 12S mutants. Since EMT is critical for tumor progression, identification of the molecular mechanisms involved should elucidate novel therapeutic targets. To this end, representational difference analysis (RDA) was used to identify cDNAs upregulated in the mutant cell line. Thirty-five differentially expressed mRNAs were identified and classified into several functional categories, including nine novel cDNAs. Among the 26 known cDNAs, extracellular matrix and related proteins made up the largest group of differentially expressed genes, followed by growth factors and receptors and transcription factors. There was also an ion transporter, a cytoskeletal protein, glycosylation and amidinotransferase enzymes and proteins with unknown functions. Some of the known genes have previously been associated with EMT and/or tumor progression and thus served to validate the system to obtain the desired target genes, while other cDNAs are newly linked with dedifferentiation/malignancy. Array analyses indicated that the cDNAs were specifically upregulated in invasive or metastatic tumors, especially of breast, uterus and lung, suggesting their involvement in the progression of these tumors.
腺病毒E1A12S基因产物（WT12S）可使上皮细胞永生化，且这些细胞保留其分化特征，但某些突变体则无法做到后者。对突变体永生化上皮细胞的特征分析表明，它们经历了上皮-间质转化（EMT）。V12ras与WT12S共表达会导致良性肿瘤，但与12S突变体共表达则会导致恶性肿瘤。由于EMT对肿瘤进展至关重要，因此确定其中涉及的分子机制应能阐明新的治疗靶点。为此，采用代表性差异分析（RDA）来鉴定突变细胞系中上调的cDNA。共鉴定出35个差异表达的mRNA，并将其分为几个功能类别，包括9个新的cDNA。在26个已知的cDNA中，细胞外基质及相关蛋白构成了差异表达基因的最大组，其次是生长因子和受体以及转录因子。还有一个离子转运体、一个细胞骨架蛋白、糖基化和脒基转移酶以及功能未知的蛋白质。一些已知基因先前已与EMT和/或肿瘤进展相关，因此有助于验证该系统以获得所需的靶基因，而其他cDNA则与去分化/恶性肿瘤新相关。阵列分析表明，这些cDNA在侵袭性或转移性肿瘤中特异性上调，尤其是乳腺癌、子宫癌和肺癌，表明它们参与了这些肿瘤的进展。
