Jean D, Tellez C, Huang S, Davis D W, Bruns C J, McConkey D J, Hinrichs S H, Bar-Eli M
Department of Cancer Biology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas, TX 77030, USA.
Oncogene. 2000 May 18;19(22):2721-30. doi: 10.1038/sj.onc.1203569.
Activating transcription factor-1 (ATF-1) and cAMP-responsive element (CRE)-binding protein (CREB) have been implicated in cAMP and Ca2+-induced transcriptional activation. The expression of the transcription factors CREB and ATF-1 is upregulated in metastatic melanoma cells. However, how overexpression of ATF-1/CREB contributes to the acquisition of the metastatic phenotype remains unclear. Here, the effect of disrupting ATF-1 activity was investigated using intracellular expression of an inhibitory anti-ATF-1 single chain antibody fragment (ScFv). Intracellular expression of ScFv anti-ATF-1 in MeWo melanoma cells caused significant reduction in CRE-dependent promoter activation. In addition, expression of ScFv anti-ATF-1 in melanoma cells suppressed their tumorigenicity and metastatic potential in nude mice. ScFv anti-ATF-1 rendered the melanoma cells susceptible to thapsigargin-induced apoptosis in vitro and caused massive apoptosis in tumors transplanted subcutaneously into nude mice, suggesting that ATF-1 and its associated proteins act as survival factor for human melanoma cells. This is the first report to demonstrate the potential of ScFv anti-ATF-1 as an inhibitor of tumor growth and metastasis of solid tumor in vivo. Oncogene (2000).
激活转录因子-1（ATF-1）和环磷酸腺苷反应元件（CRE）结合蛋白（CREB）与环磷酸腺苷（cAMP）和钙离子（Ca2+）诱导的转录激活有关。转录因子CREB和ATF-1的表达在转移性黑色素瘤细胞中上调。然而，ATF-1/CREB的过表达如何导致转移性表型的获得仍不清楚。在此，使用抑制性抗ATF-1单链抗体片段（ScFv）的细胞内表达来研究破坏ATF-1活性的效果。在MeWo黑色素瘤细胞中ScFv抗ATF-1的细胞内表达导致CRE依赖的启动子激活显著降低。此外，在黑色素瘤细胞中ScFv抗ATF-1的表达抑制了它们在裸鼠中的致瘤性和转移潜能。ScFv抗ATF-1使黑色素瘤细胞在体外对毒胡萝卜素诱导的凋亡敏感，并在皮下移植到裸鼠的肿瘤中引起大量凋亡，表明ATF-1及其相关蛋白作为人类黑色素瘤细胞的生存因子。这是第一份证明ScFv抗ATF-1作为体内实体瘤肿瘤生长和转移抑制剂潜力的报告。《癌基因》（2000年）
