阴虚体质对鼻咽癌放疗敏感性的影响及其机制探讨

目的探讨阴虚体质对鼻咽癌放射敏感性的影响及其作用机制。方法于南方医院古中医科门诊诊治的鼻咽癌患者中选取符合标准的150例进行分组及体质辨识,甲基化特异性PCR检测样品组织中抑癌基因(RASSF1A、TP53、PTEN)启动子区域CpG岛的甲基状态,实时荧光定量检测其表达。结果经中医体质问卷结合中医四诊辨识患者体质,在112例放射敏感患者中,属于阴虚质者17.86%(20人),在追踪复发患者(放射抗拒)38人中,阴虚质73.68%(28人);与其他体质患者相比,阴虚体质患者中的抑癌基因(RASSF1A、TP53、PTEN)甲基化比例增加,基因表达下调。结论阴虚体质更易出现放射抗拒性,高甲基化导致的抑癌基因失活可能是阴虚质鼻咽癌患者出现放射抗拒的内在机制。

Effect and mechanism of yin deficiency constitution on radio sensitivity of nasopharyngeal carcinoma

Objective　To investigate the effect and mechanism of yin deficiency constitution on radio sensitivity of nasopharyngeal carcinoma.　Methods　150 patients with nasopharyngeal carcinoma who were treated in the traditional Chinese medicine department of Nanfang Hospital were selected for grouping and constitutional identification. Methylation-specific PCR (MSP) was used to detect the methylation status of CpG islands in the promoter region of tumor suppressor gene (RASSF1A, TP53, PTEN) and real-time fluorescence quantitative (qPCR) detection of its expression.　Results　According to the TCM Constitution Questionnaire and the four diagnoses of TCM, the constitution of the patients was identified. Among the 112 patients with radio sensitivity, 20 were yin deficiency constitution, accounting for 17.86% of the total number. Among the 38 patients who were relapsed (radiation resistance), 28 were yin deficiency constitution, accounting for 73.68% of the total number. Compared with other constitution patients, the proportion of methylation of tumor suppressor genes (RASSF1A, TP53, PTEN) in patients with yin deficiency constitution increased significantly, and gene expression was down-regulated.　Conclusions　Yin deficiency constitution is more likely to have radio resistance, and the inactivation of tumor suppressor gene caused by hypermethylation may be an intrinsic mechanism of radiation resistance in patients with yin deficiency constitution and nasopharyngeal carcinoma.