黑色素瘤缺乏因子2在结直肠癌中的表达及临床意义

Expressoin and clinical significance of Absent in melanoma 2 in tissues of colorectal cancer

目的探讨黑色素瘤缺乏因子2(AIM2)在结直肠癌组织中的表达情况及与临床病理特征的关系。方法采用荧光定量PCR技术检测64例结直肠癌新鲜冰冻组织及癌旁组织中AIM2的表达;免疫组化检测68例结直肠癌标本及癌旁组织中AIM2的蛋白水平并分析其与临床病理因素之间的关系。结果荧光定量PCR显示AIM2的mRNA水平在肿瘤组织中显著降低,与距肿瘤3~5 cm处癌旁组织相比差异有统计学意义(P<0.05);肿瘤组织AIM2蛋白的免疫反应评分和染色阳性率显著降低,与距肿瘤3~5 cm处癌旁组织相比差异有统计学意义(P<0.05);AIM2蛋白免疫反应评分与肿瘤分化等级密切相关(P<0.05),肿瘤分化程度越低,AIM2的蛋白水平越低,而与年龄、性别、肿瘤位置、T分期、淋巴结转移、远处转移及TNM分期等无关。结论结直肠癌组织的AIM2表达显著下降,可能是影响结直肠癌发展的一个潜在判断指标。

Objective In this study we aimed to identify the AIM2 expression in colorectal tissues and relationship between AIM2 expression and clinic pathological parameters.Methods Paired samples of CRC tissues and corresponding non-cancerous colonic tissues from 64 CRC patients taken from surgical excision specimen were included in this study.The expression of AIM2 was analyzed by quantitative real-time PCR assay(qRT-PCR).We used immunohistochemical staining assay to evaluate the expression of AIM2 in protein level in 68 pairs of colorectal specimen,and we analyzed the relationship between AIM2 expression and clinic pathological parameters.Result The result of qRT-PCR suggested that the expression of AIM2 was significantly decreased in colorectal cancer tissues compared with the corresponding non-cancerous colonic tissues(P<0.01).The immunoreactivity score and positive rate of colorectal cancer tissues was also significantly lower than corresponding non-cancerous colonic tissues.The of colorectal cancer tissues was associated with the tumor grade of colorectal cancer.The immunoreactivity score is decreased in the one which tumor grade was lower.Conclusion The expression of AIM2 was significantly decreased in colorectal cancer tissues,and the AIM2 expression was associated with the tumor grade of colorectal cancer.