Prevalence of pks-positive Escherichia coli in Japanese patients with or without colorectal cancer.
Prevalence of pks-positive Escherichia coli in Japanese patients with or without colorectal cancer.
复制标题
DOI：
10.1186/s13099-017-0185-x
复制
发表时间：
2017
期刊：
影响因子：
4.2
通讯作者：
Koike K
中科院分区：
文献类型：
--
作者：
Shimpoh T;Hirata Y;Ihara S;Suzuki N;Kinoshita H;Hayakawa Y;Ota Y;Narita A;Yoshida S;Yamada A;Koike K
最近的研究表明，一些拥有名为 pks 岛的基因簇的大肠杆菌菌株可能在人类结直肠癌 (CRC) 的发展中发挥致病作用。在欧洲的几份报告中，与对照组相比，它们在结直肠癌患者的结肠组织标本中更常见。在这项研究中，我们试图通过在结肠镜检查期间使用非侵入性样本采集技术来阐明日本人群中 CRC 患者和非 CRC 对照之间 pks 患病率的差异。在诊断性结肠镜检查期间收集结肠灌洗样本，并提取每个样本中的细菌 DNA。然后使用传统定性 PCR 和实时定量 PCR 检查粪便 DNA 样本中的 pks 岛基因。在某些患者中，还在同一次结肠镜检查中收集了活检样本，并评估了同一患者的结肠灌洗样本和活检样本的 pks 状态之间的相关性。 13 名患者中有 12 名 (92%) 通过结肠灌洗样本和活检样本显示出相同的 pks 状态，这表明结肠灌洗样本可作为活检样本的替代品。总共收集了 98 份结肠灌洗样本，其中 35 份来自 CRC 患者，37 份来自腺瘤患者，26 份来自对照。 CRC、腺瘤和对照患者的结肠灌洗样本中分别检测到 pks 阳性细菌 DNA，比例分别为 43%、51% 和 46%，并且疾病之间没有显着差异。实时定量PCR显示疾病之间pks阳性细菌DNA的相对浓度没有显着差异。年龄、性别、CRC 位置、CRC 分期或 k-ras 基因状态与 pks 患病率无关。尽管从结肠灌洗样本中收集粪便 DNA 的方法是安全且技术上可行的，但 pks 阳性细菌以外的因素似乎在该队列中的 CRC 发展中发挥着更重要的作用。
Recent studies show that some Escherichia coli strains possessing a gene cluster named the pks island might have a causative role in the development of human colorectal cancer (CRC). In several reports from Europe, they are found more prevalently in colon tissue specimens derived from CRC patients compared to those from controls. In this study we sought to clarify the difference in pks prevalence between CRC patients and non-CRC controls in the Japanese population, by using non-invasive sample collection technique during colonoscopy. Colonic lavage samples were collected during diagnostic colonoscopy, and bacterial DNA within each sample was extracted. Fecal DNA samples were then examined for pks island genes using conventional qualitative PCR and real-time quantitative PCR. In some patients biopsy samples were also collected in the same session of colonoscopy, and the correlation between the pks status of the colonic lavage sample and the biopsy sample of the same patients was evaluated. Twelve out of thirteen patients (92%) showed the same pks status by colonic lavage sample and biopsy sample, suggesting the usefulness of colonic lavage samples as a surrogate for biopsy samples. A total of 98 colonic lavage samples were collected, which included 35 from CRC patients, 37 from adenoma patients, and 26 from controls. The pks-positive bacterial DNA was detected in 43, 51, and 46% of colonic lavage samples from CRC, adenoma, and control patients, respectively, and there was no significant difference among diseases. Real-time quantitative PCR showed no significant difference in the relative concentrations of pks-positive bacterial DNA among diseases. Age, gender, location of CRC, CRC staging, or k-ras gene status was not associated with pks prevalence. Although the method of collecting fecal DNA from colonic lavage samples was safe and technically feasible, factors other than pks-positive bacteria appear to play more important roles in CRC development in this cohort.