Human oral microbiome dysbiosis as a novel non-invasive biomarker in detection of colorectal cancer

Abstract

Background: The oral microbiome may play an important role in colorectal carcinogenesis. However, few studies have investigated the association between oral microbiome and the development of colorectal cancer (CRC). We aimed to investigate whether oral health-colorectal tumor association has an underlying microbial basis, in the quest for novel non-invasive biomarkers for CRC. Methods: We collected oral swab samples from 161 patients with CRC, 34 patients with colorectal adenoma (CRA), and 58 healthy volunteers. The oral microbiota was assessed using 16S rRNA sequencing. We characterized oral microbiome, identified microbial markers, constructed and validated colorectal tumor (CRA and CRC) classifier. Results: Oral microbial composition and diversity were significantly different among the three groups, and the CRA group had the highest diversity. Analysis of the functional potential of oral microbiota demonstrated that the pathway involving cell motility was overrepresented in the CRA and CRC groups relative to that in the healthy controls. Moreover, a random forest model was constructed based on oral microbial markers, which could distinguish the colorectal tumor groups from the healthy controls and achieve a powerful classification potential in the discovery and validation cohorts. Conclusion: This study suggests a potential association between oral microbiome dysbiosis and colorectal cancer. Oral microbiota-based biomarkers may be helpful in predicting the risks for the development of CRA and CRC.

Bacteria Residing at Root Canals Can Induce Cell Proliferation and Alter the Mechanical Properties of Gingival and Cancer Cells

“…Zhang et al concluded that oral squamous cell cancer (OSCC) tissues were enriched in oral bacteria, including Fusobacterium , Alloprevotella , and Porphyromonas , when compared to control tissues, suggesting potential association between these bacteria and OSCC [ 35 ]. Most recently, human oral microbiome dysbiosis was also proposed as non-invasive biomarker of colorectal adenoma and colorectal cancer, and a colorectal adenoma group of patients was reported to be characterized by the largest oral microbial composition and diversity [ 36 ].…”

Fusobacterium nucleatum Acts as a Pro-carcinogenic Bacterium in Colorectal Cancer: From Association to Causality

“…Oral samples examined mainly include saliva, oral wash, tongue coating, and oral swabs ( Zhang et al, 2020 ). The oral microbiota has been associated with several cancers, such as pancreatic cancer ( Fan et al, 2018 ), esophageal cancer ( Peters et al, 2017 ), and CRC ( Han, 2014 ).…”

“…In contrast to the cross-sectional clinical studies, this study gives some hints for the cause-effect relationship between F. nucleatum and CRC. Oral samples examined mainly include saliva, oral wash, tongue coating, and oral swabs (Zhang et al, 2020). The oral microbiota has been associated with several cancers, such as pancreatic cancer (Fan et al, 2018), esophageal cancer (Peters et al, 2017), and CRC (Han, 2014).…”

Oral Microbiome Signatures in Hematological Cancers Reveal Predominance of Actinomyces and Rothia Species

“…interact with the host in a manner that, in fact, would contribute to lymphoma (or other hematological cancer) progression or if BC contributes to an overall dysbiosis of the oral microbiome, leading to the progression of cancer. As multiple studies have suggested, it is likely that dysbiosis contributes to the development of cancer [ 28 , 29 , 30 ]. Indeed, an oral transfer to gut of the Actinomyces species could potentially activate inflammatory processes, as suggested by the work of Chua et al, who showed that increased abundance in phylum Actinobacteria in the gut was associated with increased immune activation in ALL survivors experiencing chronic inflammation [ 12 ].…”