收集了93例结直肠癌（CRC）患者和30个健康对照组（非CRC）的口腔和肠道样本进行菌群分析。利用唾液（28个非CRC和94个CRC）、粪便（30个非CRC和97个CRC）、牙下分泌液（CRC患者20例）和肿瘤组织样本（CRC患者20例），进行了16S metabarcoding和/或RNA测序（RNAseq）分析。使用ANCOM-BC软件包进行的丰度差异分析，通过Holm-Bonferroni方法调整p值后发现，与健康对照组相比，CRC患者的粪便中Parvimonas显著过表达（p值 <0.001）。从CRC患者的口腔和腺癌中共分离获得了11株Parvimonas micra菌株。基因组分析发现，来自同一患者的一对菌株共享99.2%的相似性，表明P. micra可以从牙下腔跃迁到肠道。数据表明，P. micra可能与其他牙周病菌协同迁移。自发推测，肿瘤中口腔细菌的活性比非肿瘤组织更高。我们建议，P. micra可以被视为在非侵入性样本（如粪便）中检测到的CRC生物标志物。该文章受版权保护，版权所有。

Oral and intestinal samples from a cohort of 93 colorectal cancer (CRC) patients and 30 healthy controls (non-CRC) were collected for microbiome analysis. Saliva (28 non-CRC and 94 CRC), feces (30 non-CRC and 97 CRC), subgingival fluid (20 CRC) and tumor tissue samples (20 CRC) were used for 16S metabarcoding and/or RNA sequencing (RNAseq) approaches. A differential analysis of the abundance, performed with the ANCOM-BC package, adjusting the p-values by the Holm-Bonferroni method, revealed that Parvimonas was significantly over-represented in feces from CRC patients (p-value <0.001) compared to healthy controls. A total of 11 Parvimonas micra isolates were obtained from the oral cavity and adenocarcinoma of CRC patients. Genome analysis identified a pair of isolates from the same patient that shared 99.2% identity, demonstrating that P. micra can translocate from the subgingival cavity to the gut. The data suggest that P. micra could migrate in a synergistic consortium with other periodontal bacteria. Metatranscriptomics confirmed that oral bacteria were more active in tumor than in non-neoplastic tissues. We suggest that P. micra could be considered as a CRC biomarker detected in non-invasive samples such as feces.This article is protected by copyright. All rights reserved.