CAJ | 학술논문

目的探讨粪便中T淋巴细胞成熟相关蛋白(MAL)、细胞周期依赖性激酶抑制因子2A(CDKN2A)和6-氧-甲基鸟嘌呤DNA甲基转移酶(MGMT)基因甲基化状态及其在结直肠癌和癌前病变筛查中的价值.方法收集69例结直肠癌、24例腺瘤、19例增生性息肉患者及26名健康人群的清晨粪便标本,提取其DNA并进行亚硫酸氢盐修饰处理,采用甲基化特异性PCR技术分析MAL、CDKN2A及MGMT甲基化状态,分析其与结直肠癌临床病理特征的关系,并比较3个基因甲基化联合检测与粪隐血试验(FOBT)的诊断敏感性.结果结直肠癌患者粪便DNA中MAL、CDKN2A、MGMT基因启动子甲基化率分别为78.3%、52.5%、55.1%,腺瘤患者分别为58.3%、41.7%、37.5%,增生性息肉患者分别为26.3%、15.8%、10.5%,正常对照人群分别为3.8%、0、3.8%;结直肠癌和腺瘤患者3个基因甲基化水平均显著高于增生性息肉患者和正常对照人群(均P＜0.05).3个基因甲基化联合检测诊断结直肠癌和腺瘤敏感度分别为92.8%和70.8%,明显高于FOBT的29.0%和25.0%(均P＜0.05).3个基因甲基化状态与结直肠癌患者的性别、年龄、肿瘤部位、淋巴结转移、远处转移及TNM分期均无关(均P＞0.05).结论粪便中MAL、CDKN2A、MGMT基因启动子甲基化水平在结直肠癌和腺瘤患者中明显升高,其联合检测可望成为结直肠癌及其癌前病变筛查的非侵入性检测方法.
목적 탐토분편중T림파세포성숙상관단백(MAL)、세포주기의뢰성격매억제인자2A(CDKN2A)화6-양-갑기조표령DNA갑기전이매(MGMT)기인갑기화상태급기재결직장암화암전병변사사중적개치.방법 수집69례결직장암、24례선류、19례증생성식육환자급26명건강인군적청신분편표본,제취기DNA병진행아류산경염수식처리,채용갑기화특이성PCR기술분석MAL、CDKN2A급MGMT갑기화상태,분석기여결직장암림상병리특정적관계,병비교3개기인갑기화연합검측여분은혈시험(FOBT)적진단민감성.결과 결직장암환자분편DNA중MAL、CDKN2A、MGMT기인계동자갑기화솔분별위78.3%、52.5%、55.1%,선류환자분별위58.3%、41.7%、37.5%,증생성식육환자분별위26.3%、15.8%、10.5%,정상대조인군분별위3.8%、0、3.8%;결직장암화선류환자3개기인갑기화수평균현저고우증생성식육환자화정상대조인군(균P＜0.05).3개기인갑기화연합검측진단결직장암화선류민감도분별위92.8%화70.8%,명현고우FOBT적29.0%화25.0%(균P＜0.05).3개기인갑기화상태여결직장암환자적성별、년령、종류부위、림파결전이、원처전이급TNM분기균무관(균P＞0.05).결론 분편중MAL、CDKN2A、MGMT기인계동자갑기화수평재결직장암화선류환자중명현승고,기연합검측가망성위결직장암급기암전병변사사적비침입성검측방법.
Objective To evaluate association between DNA methylation of MAL, CDKN2A,and MGMT in stool and development of colorectal cancer, and to evaluate the screening value of these biomarkers in colorectal cancer and pre-malignant lesions. Methods Morning stool specimens were collected from 69 patients with colorectal cancer, 24 with colon adenoma, 19 with hyperplastic polyps,and 26 healthy controls. DNA was extracted and treated with bisulfite. Methylation-specific PCR(MSP)was performed for methylation analysis of MAL, CDKN2A and MGMT in DNA samples. Associations between clinicopathological features and gene methylation were analyzed. The sensitivity of diagnosis by combining three methylation markers was compared with fecal occult blood test (FOBT). Results The methylation frequencies of MAL, CDKN2A and MGMT were 78.3%, 52.5% and 55.1% in colorectal cancer, 58.3%, 41.7% and 37.5% in colon adenomas, 26.3%, 15.8% and 10.5% in hyperplastic polyps, and 3.8%, 0 and 3.8% in healthy controls, respectively. Significant differences in three genes were found between colorectal cancer and hyperplastic polyp, colorectal cancer and healthy control,colon adenoma and hyperplastic polyp, colon adenoma and healthy control (all P＜0.05). The diagnostic sensitivity by com bining three methylation markers was 92.8% in colorectal cancer, 70.8% in colon adenomas, significantly higher than FOBT examination (29.0% in colorectal cancer and 25.0% in colon adenomas, all P＜0.05). No significant associations existed between three genes methylation of the three genes and clinical characteristic including sex, age, tumor location, lymph node metastases and TNM stage (all P＞0.05). Conclusion DNA methylations levels of MAL, CDKN2A, and MGMT in stools are significantly higher in colorectal cancer and colon adenoma, which may serve as an noninvasive approach for the screening of colorectal cancer and pre-malignant lesions.