Yehya Ashwaq Hamid, Yusoff Narazah Mohd, Khalid Imran A, Mahsin Hakimah, Razali Ruzzieatul Akma, Azlina Fatimah, Mohammed Kamil Sheikh, Ali Syed A
Advanced Medical and Dental Institute, Universiti Sains Malaysia, Hospital Seberang Jaya, Pulau Pinang, Malaysia.
Asian Pac J Cancer Prev. 2012;13(5):1869-72. doi: 10.7314/apjcp.2012.13.5.1869.
To assess the diagnostic potential of tumor-associated high molecular weight DNA in stool samples of 32 colorectal cancer (CRC) patients compared to 32 healthy Malaysian volunteers by means of polymerase chain reaction (PCR).
Stool DNA was isolated and tumor-associated high molecular weight DNA (1.476 kb fragment including exons 6-9 of the p53 gene) was amplified using PCR and visualized on ethidium bromide-stained agarose gels.
Out of 32 CRC patients, 18 were positive for the presence of high molecular weight DNA as compared to none of the healthy individuals, resulting in an overall sensitivity of 56.3% with 100% specificity. Out of 32 patients, 23 had tumor on the left side and 9 on the right side, 16 and 2 being respectively positive. This showed that high molecular weight DNA was significantly (p=0.022) more detectable in patients with left side tumor (69.6% vs 22.2%). Out of 32 patients, 22 had tumors larger than 1.0 cm, 18 of these (81.8%) being positive for long DNA as compared to not a single patient with tumor size smaller than 1.0 cm (p<0.001).
We detected CRC-related high molecular weight p53 DNA in stool samples of CRC patients with an overall sensitivity of 56.3% with 100% specificity, with a strong tumor size dependence.
通过聚合酶链反应（PCR）评估32例结直肠癌（CRC）患者粪便样本中肿瘤相关高分子量DNA相对于32名健康马来西亚志愿者的诊断潜力。
分离粪便DNA，使用PCR扩增肿瘤相关高分子量DNA（包含p53基因外显子6 - 9的1.476 kb片段），并在溴化乙锭染色的琼脂糖凝胶上进行可视化分析。
32例CRC患者中，18例高分子量DNA呈阳性，而健康个体均为阴性，总体灵敏度为56.3%，特异性为100%。32例患者中，23例肿瘤位于左侧，9例位于右侧，分别有16例和2例呈阳性。这表明左侧肿瘤患者中高分子量DNA的可检测性显著更高（p = 0.022）（69.6%对22.2%）。32例患者中，22例肿瘤大于1.0 cm，其中18例（81.8%）长链DNA呈阳性，而肿瘤大小小于1.0 cm的患者无一例阳性（p < 0.001）。
我们在CRC患者的粪便样本中检测到与CRC相关的高分子量p53 DNA，总体灵敏度为56.3%，特异性为100%，且与肿瘤大小密切相关。
