Antognelli Cinzia, Del Buono Chiara, Baldracchini Francesca, Talesa Vincenzo, Cottini Emanuele, Brancadoro Celestino, Zucchi Alessandro, Mearini Ettore
Department of Experimental Medicine, University of Perugia, Perugia, Italy.
Cancer Biol Ther. 2007 Dec;6(12):1880-8. doi: 10.4161/cbt.6.12.4961. Epub 2007 Sep 1.
Glyoxalase system, a ubiquitous detoxification pathway protecting against cellular damage caused by potent cytotoxic metabolites, is involved in the regulation of cellular growth. Aberrations in the expression of glyoxalase genes in several human cancers have been reported. Recently, we described a possible regulatory effect by estrogens on glyoxalase genes in human breast cancer cell lines. This result, along with those ones regarding changes in glyoxalases activity and expression in other human hormone-regulated cancers, such as prostate cancer, has prompted us to investigate whether also androgens, whose functional role in prostate cancer pathogenesis is well known, could modulate glyoxalases gene expression. Therefore, we treated LNCaP androgen-responsive and PC3 androgen-independent human prostate cancer cell lines with testosterone at the concentrations of 1 nM and 100 nM. After a two days treatment, glyoxalases mRNA levels as well as cell proliferation were evaluated by real-time RT-PCR analysis and [3H]thymidine incorporation, respectively. Results pointed out that testosterone affects the expression of glyoxalase system genes and cell proliferation in a different manner in the two cell lines. The possibility that modulation of glyoxalase genes expression by testosterone is due to glyoxalases-mediated intracellular response mechanisms to the androgen-induced oxidative stress or to the presence of androgen response elements (ARE) in glyoxalase promoters are discussed. Knowledge regarding the regulation of glyoxalases by testosterone may provide insights into the importance of these enzymes in human prostate carcinomas in vivo.
乙二醛酶系统是一种普遍存在的解毒途径,可防止由强效细胞毒性代谢产物引起的细胞损伤,参与细胞生长的调节。已有报道称几种人类癌症中乙二醛酶基因的表达存在异常。最近,我们描述了雌激素对人乳腺癌细胞系中乙二醛酶基因可能的调节作用。这一结果,连同其他人类激素调节癌症(如前列腺癌)中乙二醛酶活性和表达变化的相关结果,促使我们研究同样在前列腺癌发病机制中功能作用明确的雄激素是否也能调节乙二醛酶基因表达。因此,我们用浓度为1 nM和100 nM的睾酮处理LNCaP雄激素反应性和PC3雄激素非依赖性人前列腺癌细胞系。经过两天的处理后,分别通过实时RT-PCR分析和[3H]胸腺嘧啶核苷掺入法评估乙二醛酶mRNA水平以及细胞增殖情况。结果指出,睾酮在这两种细胞系中以不同方式影响乙二醛酶系统基因的表达和细胞增殖。文中讨论了睾酮对乙二醛酶基因表达的调节可能是由于乙二醛酶介导的细胞内对雄激素诱导的氧化应激的反应机制,或者是由于乙二醛酶启动子中存在雄激素反应元件(ARE)。关于睾酮对乙二醛酶调节的知识可能为这些酶在人前列腺癌体内的重要性提供见解。