Kawano Atsuko, Ishikawa Hideki, Mutoh Michihiro, Kubota Hiroyuki, Matsuda Kazunori, Tsuji Hirokazu, Matsumoto Kazumasa, Nomoto Koji, Tanaka Ryuichiro, Nakamura Tomiyo, Wakabayashi Keiji, Sakai Toshiyuki
Institute of Gastroenterology, Zenjinkai Shimin-no-Mori Hospital, Miyazaki, Japan.
Department of Molecular-Targeting Cancer Prevention, Kyoto Prefectural University of Medicine, Kyoto, Japan.
Oncotarget. 2018 Apr 20;9(30):21459-21467. doi: 10.18632/oncotarget.25130.
Intestinal bacteria play an important role in human health. This prospective cohort study aimed to investigate the relationship between the abundance of different intestinal bacteria and the risk of developing colorectal cancer (CRC). Fecal samples from CRC patients ( 157) were collected at the start of the study wherein patients subsequently underwent endoscopy to remove polyps. Gut bacteria were isolated by using specific culture methods and the fecal counts of various bacteria were quantified by reverse-transcription-quantitative-PCR (RT-qPCR) assays. The obtained data were subjected to cohort analysis in relation to the incidence of colorectal adenomas after 4 years of intervention. No relationship was detected between the counts of major intestinal bacteria and the incidence of colorectal adenomas. However, interestingly, a significant negative correlation was noted between colorectal adenoma incidence and the counts of bacteria grown on Columbia blood agar base (COBA) ( 0.007). The risk ratio of colorectal adenomas was 0.58 (95% CI: 0.35-0.96) in the group with the highest bacterial count compared to the lowest. Bacteria grown on COBA were more abundant in older patients, non-smoking patients, and patients with a lower body mass index. The RT-qPCR results revealed a significantly lower colorectal adenoma incidence in subjects with higher enterococcal count as compared to subjects with a lower count, with a risk ratio of 0.47 (95% CI: 0.30-0.76). Correlation of a higher enterococci count with a lower risk of CRC development suggests that certain Enterococcus strains may have adenoma suppressive effects.
肠道细菌在人类健康中起着重要作用。这项前瞻性队列研究旨在调查不同肠道细菌的丰度与患结直肠癌（CRC）风险之间的关系。在研究开始时收集了157例CRC患者的粪便样本，这些患者随后接受了内镜息肉切除手术。通过特定培养方法分离肠道细菌，并采用逆转录定量聚合酶链反应（RT-qPCR）测定法对各种细菌的粪便计数进行定量。将获得的数据进行队列分析，以研究干预4年后结直肠腺瘤的发病率。未发现主要肠道细菌计数与结直肠腺瘤发病率之间存在关联。然而，有趣的是，结直肠腺瘤发病率与在哥伦比亚血琼脂基础培养基（COBA）上生长的细菌计数之间存在显著负相关（P = 0.007）。细菌计数最高组与最低组相比，结直肠腺瘤的风险比为0.58（95%置信区间：0.35 - 0.96）。在老年患者、非吸烟患者和体重指数较低的患者中，在COBA上生长的细菌更为丰富。RT-qPCR结果显示，肠球菌计数较高的受试者与计数较低的受试者相比，结直肠腺瘤发病率显著降低，风险比为0.47（95%置信区间：0.30 - 0.76）。较高的肠球菌计数与较低的CRC发生风险之间的相关性表明，某些肠球菌菌株可能具有抑制腺瘤的作用。
