Sierra-Torres Carlos H, Arboleda-Moreno Yexania Y, Orejuela-Aristizabal Leonora
Laboratorio de Genética Humana, Departamento de Ciencias Fisiológicas, Facultad de Ciencias de la Salud, Universidad del Cauca, Popayán, Colombia.
Environ Mol Mutagen. 2006 Aug;47(7):553-61. doi: 10.1002/em.20228.
Cervical cancer is the second leading cause of death from cancer among women in Colombia (16/100,000). Infection with high-risk human papillomavirus (HPV) plays a major role in the etiology of high-grade squamous intraepithelial lesions (HSILs). Exposure to chemical agents may be a cofactor for tumor induction, and individual genetic differences in the metabolism of these chemical agents may affect the susceptibility of individuals towards the development of HSIL. In this case-control study, a total of 91 cases with HSIL and 92 healthy controls, frequency-matched by age and place of origin, were recruited, and their frequencies of CYP2E1, GSTM1, and GSTT1 polymorphism were determined. We then evaluated the association of these polymorphisms, by themselves and in combination with wood smoke exposure and HPV-infection status, with the risk of HSIL. The results indicate that GSTM1 and GSTT1 polymorphism were not associated with HSIL, although a small increase in risk was observed for individuals who were GSTT1 null (OR = 1.4, 95% CI = 0.57-3.44). Contrary to other investigations, the c2/c2 variant of the CYP2E1 gene was associated with a significant increase in risk after adjusting for wood smoke exposure (OR = 6.3, 95% CI = 1.10-36.38) or wood smoke exposure and HPV-infection status (OR = 10.7, 95% CI = 1.76-65.58). Wood smoke exposure also increased the risk of HSIL among CYP2E1 c2/c2 HPV-positive women (OR = 3.3, CI = 0.50-22.50); however, the increase did not achieve statistical significance. Our study provides tantalizing evidence that genetic differences in the metabolism of wood smoke carcinogens, particularly metabolism by CYP2E1, may confer susceptibility for HSIL development. Further investigations with larger populations will be needed to confirm this association, which may provide important information for improving cervical cancer prevention programs.
宫颈癌是哥伦比亚女性癌症死亡的第二大主要原因(每10万人中有16人)。高危型人乳头瘤病毒(HPV)感染在高级别鳞状上皮内病变(HSIL)的病因中起主要作用。接触化学物质可能是肿瘤诱发的一个辅助因素,而这些化学物质代谢过程中的个体遗传差异可能会影响个体对HSIL发生的易感性。在这项病例对照研究中,共招募了91例HSIL患者和92名健康对照者,按照年龄和籍贯进行频率匹配,并测定了他们CYP2E1、GSTM1和GSTT1基因多态性的频率。然后,我们评估了这些多态性本身以及与木烟暴露和HPV感染状态相结合时与HSIL风险的关联。结果表明,GSTM1和GSTT1基因多态性与HSIL无关,尽管GSTT1基因缺失的个体风险略有增加(OR = 1.4,95%CI = 0.57 - 3.44)。与其他研究相反,在调整木烟暴露(OR = 6.3,95%CI = 1.10 - 36.38)或木烟暴露和HPV感染状态(OR = 10.7,95%CI = 1.76 - 65.58)后,CYP2E1基因的c2/c2变体与风险显著增加相关。木烟暴露也增加了CYP2E1 c2/c2 HPV阳性女性患HSIL的风险(OR = 3.3,CI = 0.50 - 22.50);然而,这种增加未达到统计学显著性。我们的研究提供了诱人的证据,表明木烟致癌物代谢中的遗传差异,特别是CYP2E1的代谢,可能会使人易患HSIL。需要对更多人群进行进一步研究以证实这种关联,这可能为改进宫颈癌预防计划提供重要信息。