c-Fos is upregulated in the genital tubercle of DEHP-induced hypospadiac rats and the prepuce of patients with hypospadias

This study aimed to investigate the expression of Fos proto-oncogene, AP-1 transcription factor subunit (c-Fos) in the genital tubercle (GT) of rats with di(2-ethylhexyl) phthalate (DEHP)-induced hypospadias and in the prepuce of patients with hypospadias compared with unaffected controls. Pregnant rats were given 750 mg/kg/day DEHP orally from gestational days 12–19. Western blotting showed that c-Fos expression was increased in DEHP-induced hypospadiac male offspring. In addition, 30 prepuce tissue specimens obtained during hypospadias repair surgery were divided into 2 groups: the mild hypospadias group (n = 15) and the severe hypospadias group (n = 15). Fifteen normal prepuce tissue specimens were harvested during elective circumcision as normal controls. Real-time quantitative polymerase chain reaction, western blotting and immunohistochemistry analyses were used to assess c-Fos expression. c-Fos protein levels were higher in the GT of DEHP-induced rats than in that of control rats. c-Fos mRNA and protein levels were also higher in the hypospadias groups than in the control group (<i>p</i> &lt; 0.05, <i>p</i> &lt; 0.001), and c-Fos protein levels were significantly higher in the severe hypospadias group than in the mild hypospadias group (<i>p</i> &lt; 0.01). The expression of c-Fos was increased in both the GT of DEHP-induced hypospadiac rats and the prepuce of hypospadias patients. Thus, c-Fos overexpression might contribute to hypospadias. <b>Abbreviations:</b> DEHP: di(2-ethylhexyl) phthalate; c-Fos: Fos proto-oncogene, AP-1 transcription factor subunit; Mafb: the masculinization-regulatory gene v-maf musculoaponeurotic fibrosarcoma oncogene family, protein B; GT: genital tubercle; ED: embryonic day; AGD: anogenital distance; AGI: anogenital distance index; ED: embryonic day.

本研究旨在探讨二(2-乙基己基)邻苯二甲酸酯（di(2-ethylhexyl) phthalate, DEHP）诱导的尿道下裂模型大鼠生殖结节（genital tubercle, GT），以及尿道下裂患者包皮组织与健康对照者包皮组织中Fos原癌基因AP-1转录因子亚基（Fos proto-oncogene, AP-1 transcription factor subunit, c-Fos）的表达情况。妊娠大鼠于妊娠第12~19天经口给予750 mg/kg/天的DEHP。蛋白质免疫印迹（Western blotting）结果显示，DEHP诱导的尿道下裂雄性子代大鼠的c-Fos表达水平升高。此外，本研究收集了30份尿道下裂修复术中获取的包皮组织标本，分为轻度尿道下裂组（n=15）与重度尿道下裂组（n=15）；另选取15份择期包皮环切术获取的正常包皮组织标本作为正常对照。采用实时定量聚合酶链反应、蛋白质免疫印迹及免疫组织化学分析，对c-Fos的表达水平进行检测。DEHP诱导组大鼠的生殖结节中c-Fos蛋白水平高于对照组大鼠。尿道下裂组的c-Fos mRNA及蛋白水平均高于对照组（p<0.05，p<0.001），且重度尿道下裂组的c-Fos蛋白水平显著高于轻度尿道下裂组（p<0.01）。综上，DEHP诱导的尿道下裂模型大鼠生殖结节与尿道下裂患者包皮组织中均存在c-Fos表达上调，提示c-Fos过表达可能参与尿道下裂的发生发展。**缩写说明:** DEHP：二(2-乙基己基)邻苯二甲酸酯（di(2-ethylhexyl) phthalate）；c-Fos：Fos原癌基因AP-1转录因子亚基（Fos proto-oncogene, AP-1 transcription factor subunit）；Mafb：雄性化调控基因v-maf肌纤维母细胞肉瘤癌基因家族蛋白B（the masculinization-regulatory gene v-maf musculoaponeurotic fibrosarcoma oncogene family, protein B）；GT：生殖结节（genital tubercle）；ED：胚胎天数（embryonic day）；AGD：肛门生殖器距离（anogenital distance）；AGI：肛门生殖器距离指数（anogenital distance index）；ED：胚胎天数（embryonic day）。