Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, P.O.BOX: 1985717411, Tehran, Iran,.
Microb Pathog. 2018 Nov;124:244-249. doi: 10.1016/j.micpath.2018.08.035. Epub 2018 Aug 22.
Colon cancer (CRC) is a heterogeneous disorder, arising from precursors-adenoma and serrated polyp. Previous studies have demonstrated the relationship between the human gut microbiota and CRC; however, its correlation to the different early precursors of CRC is not properly understood. Here, we studied the relationship between targeted gut bacteria and different colorectal polyp types, location, size and grade of dysplasia.
In the present case-control descriptive study, selected fecal bacteria were assessed in 118 patients, referred for standard screening colonoscopy, including 31 normal controls, 21 hyperplastic polyp (HP), 16 sessile serrated polyp (SSA), 29 tubular adenoma (TA) and 21 villous/tubuvillous polyp (VP/TVP) cases, between 2015 and 2017, by absolute quantitative real time PCR technique (q PCR) in different ethnicity of Iranian population. The panel of bacteria was including Streptococcus bovis/gallolyticus, Enterococcus faecalis, Enterotoxigenic Bacteroides fragilis (ETBF), Fusobacterium nucleatum, Porphyromonas spp., Lactobacillus spp., Roseburia spp., and Bifidobacterium spp.
Higher numbers of F. nucleatum, E. feacalis, S. bovis, ETBF and Porphyromonas spp. were detected in AP cases, consisting TA and especially VP/TVP, in contrast to samples from the normal, HP and SSA groups (P < 0.001). On the contrary, lower number of Lactobacillus spp., Roseburia spp. and Bifidobacterium spp. were detected in AP, compared to the normal, HP and SSA. Surprisingly, a significant correlation was found among selected gut bacterial quantity, the size, location and grade of dysplasia of polyp cases.
These findings suggest that gut bacteria might contribute in early stages of colorectal carcinogenesis through the development of AP, but not SSA. In fact, AP and SSA are also different in terms of molecular pathways and tendencies to present in specific colorectal location. Overall, these findings may lead to development of CRC prevention therapies, targeting early protagonist bacteria of colorectal carcinogenesis from AP.
结肠癌（CRC）是一种异质性疾病，由前体腺瘤和锯齿状息肉引起。先前的研究已经证明了人类肠道微生物群与 CRC 之间的关系；然而，其与 CRC 不同早期前体的相关性尚不清楚。在这里，我们研究了靶向肠道细菌与不同结直肠息肉类型、位置、大小和异型增生程度之间的关系。
在本病例对照描述性研究中，选择了 118 名因标准筛查结肠镜检查而就诊的患者的粪便细菌进行评估，包括 31 名正常对照、21 名增生性息肉（HP）、16 名无蒂锯齿状息肉（SSA）、29 名管状腺瘤（TA）和 21 名绒毛/管状绒毛息肉（VP/TVP），这些患者于 2015 年至 2017 年在伊朗不同种族人群中通过绝对定量实时 PCR 技术（qPCR）进行检测。细菌检测包括牛链球菌/肠球菌、粪肠球菌、产肠毒素脆弱拟杆菌（ETBF）、具核梭杆菌、卟啉单胞菌、乳杆菌、罗氏菌和双歧杆菌。
AP 病例（包括 TA 尤其是 VP/TVP）中检测到更多数量的 F. nucleatum、E. feacalis、S. bovis、ETBF 和卟啉单胞菌，而与正常、HP 和 SSA 组相比（P<0.001）。相反，AP 中检测到的乳杆菌、罗氏菌和双歧杆菌数量较少。令人惊讶的是，在选定的肠道细菌数量与息肉病例的大小、位置和异型增生程度之间发现了显著的相关性。
这些发现表明，肠道细菌可能通过 AP 的发展在结直肠癌的早期阶段发挥作用，但不是 SSA。事实上，AP 和 SSA 在分子途径和在特定结直肠位置出现的趋势方面也有所不同。总的来说，这些发现可能会导致开发针对结直肠癌发生的早期主角细菌的 CRC 预防疗法。
