燃煤污染型地方性砷中毒患者皮肤组织P14ARF和MDM2及突变型P53蛋白表达

摘要

目的 观察燃煤污染型地方性砷中毒患者皮肤组织突变型P53( P53mt)蛋白及其下游基因P14ARG、MDM2蛋白的表达水平,为揭示砷致皮肤损害的分子机制提供依据.方法 以自愿手术治疗的60例燃煤污染型地方性砷中毒患者作为观察对象,依据皮肤病理学诊断分为一般皮肤病变组(35例)、癌前病变组(19例)、癌变组(6例)；以某医院经病理学诊断无异常的非肿瘤手术患者的9例皮肤组织为对照,采用免疫组织化学EnVision二步法检测皮肤组织中P14ARF、MDM2和P53mt蛋白的表达情况.结果 4组皮肤组织P14ARF蛋白表达阳性率比较,差异有统计学意义(x2=9.39,P＜0.05)；其中癌前病变组、癌变组[46.1％(6/19)、33.3％(2/6)]明显低于对照组[88.9％(8/9),P均＜0.05]；且随着皮肤病变程度的加重,P14ARF蛋白表达呈降低趋势(P＜0.05).4组皮肤组织MDM2、P53mt蛋白表达阳性率比较,差异有统计学意义(x2值分别为6.21、20.64,P均＜ 0.05)；其中一般病变组、癌前病变组和癌变组[54.2％( 19/35)、63.2％(10/19)、66.7％(4/6)和25.7％(9/35)、73.7％(14/19)、83.3％(5/6)]明显高于对照组(0、0,P均＜0.05)；随着皮肤病变程度的加重,MDM2和P53mt蛋白表达呈增强趋势(P均＜0.05).结论 燃煤污染型地方性砷中毒患者皮肤组织P53mt蛋白表达阳性率升高,且P14ARF和MDM2蛋白表达异常,后者所致的细胞周期和凋亡调控失常可能是砷致皮肤病损发生发展的原因之一.%Objective To determine the protein expression of P14ARF,MDM2 and mutant type P53 (P53mt) in skin specimens of coal-burning-type of endemic arseniasis patients and to reveal the molecular mechanism of the disease.Methods Sixty skin specimens from 60 endemic arseniasis patients including 35 of skin lesions patients,19 of precancerous lesion and 6 of skin cancer and 9 normal skin specimens from non-cancer patients were studied.Expression of P14~,MDM2 and P53mt was evaluated by immunohistochemistry using corresponding monoclonal antibodies.Results There was significant difference in the positive rates of P14ARF,MDM2 and P53mt among the 4 groups(x2 =9.39,6.21,20.64,all P ＜ 0.05).The positive rates of P14ARF in precancerous lesion and skin cancer specimens were 46.1％ (6/19) and 33.3％ (2/6),respectively,which were significantly lower than that of the normal skin specimens [88.9％(8/9),all P ＜ 0.05].Decreased expression of P14ARF was correlated with the development of dermopathy (P ＜ 0.05).The positive rates of MDM2 and P53mt in skin lesions,precancerous lesion and skin cancer specimens were 54.2％ ( 19/35 ),63.2％ (10/19),66.7％ (4/6) and 25.7％(9/35),73.7％(14/19),83.3％(5/6),respectively,which were significantly higher than those of the control (0,0,all P＜ 0.05).The expression of MDM2 and P53mt increased with the development of dermopathy(all P ＜ 0.05).Conclusions P53mt protein in skin tissue of coal-burning-type of endemic arseniasis patients is over expressed.Abnormal expression of P14ARF and MDM2 may be one of the reasons lead to abnormal cell cycle control disorders and may play a role in the development of endemic arseniasis.