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

Abstract

The endogenous microbiome of healthy individuals in oral cavities is diverse, representing over 700 bacterial species. Imbalance in oral and gut microbiome composition and associated gene expression has been linked to different forms of hematological (blood) cancers. Our objective is to compare oral microbiome profiles of patients with blood cancers (BC group: N = 39 patients, n = 124 oral samples) to those of healthy control subjects (HC group: N = 27 subjects, n = 100 oral samples). Saliva samples and swabs of buccal mucosa, supragingival plaque, and tongue were collected from blood cancer patients and healthy controls. Next-generation sequencing (16S-rRNA gene V3–V4 region) was used to determine the relative abundance of bacterial taxa present at the genus and species levels. Differences in oral microbiome beta-diversity were determined using multivariate permutational analysis of variance (PERMANOVA). Linear discriminant analysis (LDA) effect size (LEfSe) analysis was performed to identify differentiating bacterial taxa in pairwise comparisons. The PATRICv3.6.7 online tool was used to determine the predominance of potential pathogenicity in the BC group. The oral microbiome beta-diversities of the BC and HC groups differed and corresponded to a reduced alpha-diversity in the BC group. LEfSe analysis showed significant LDA scores for Actinomyces and Rothia spp., differentiating the BC group from the HC group. In silico analysis using PATRICv3.6.7 demonstrated that the groups of bacteria possessing traits of “antibiotic resistance”, “oral pathogen”, and “virulence” was enriched in the BC group. Although 56% of the BC patients received antibiotics within two weeks of the oral bacterial sampling, Actinomyces genus remained the top differentiating feature in the BC group regardless of the administration of antibiotics, while Rothia dentocariosa was detected as the top differentiating feature in the BC patients who did not receive antibiotics, but not in those who received antibiotics. Further investigation is needed to better understand the interactions of certain oral species with the host immune system to better characterize clinically relevant associations with hematological cancers.

L-norvaline affects the proliferation of breast cancer cells based on the microbiome and metabolome analysis

“…However, which host factor causes Actinomyces colonization in breast cancer patients needs to be further explored. Studies have shown that Actinomyces could invade damaged mucosa with reduced mucosal protection (Clarridge 3rd & Zhang, 2002; Mougeot et al, 2020). Malignancy‐like symptoms caused by Actinomyces have been reported previously (Roh et al, 2019; Savoca et al, 2019).…”

Haemophilus pittmaniae and Leptotrichia spp. Constitute a Multi-Marker Signature in a Cohort of Human Papillomavirus-Positive Head and Neck Cancer Patients

“…PERMANOVA analyses were performed using a mixed model with unrestricted permutation of raw data, 9,999 permutations, and type III partial sum of squares ( Clarke and Gorley, 2006 ), as previously implemented ( Mougeot et al, 2019 , 2020 ). Fixed factors were “Diagnosis” (e.g., HNC vs. HC) and “Sample site” (B, P, S, and T).…”

“…Overall, without implying a causal effect, a link between oral microbiome dysbiosis and cancer has been suggested by several studies ( Kudo et al, 2016 ; Hayes et al, 2018 ; Mohammed et al, 2018 ; Wu et al, 2018 ; Mougeot et al, 2020 ). For instance, Fusobacterium nucleatum was found overabundant in the oral cavity of patients with colon cancer and lymph node metastasis ( Kudo et al, 2016 ).…”

Chemotherapy-associated oral microbiome changes in breast cancer patients

“…We aimed to analyze (1) the oral microbial community and potential changes to the community pattern upon chemotherapy in breast cancer patients and (2) a potential role of Actinomyces ssp. during the course of therapy as a suspected pathogen for the development of oral diseases ( 26 ). We suggest that chemotherapy in general changes the oral microbiome as already demonstrated and reviewed for the gut microbiome ( 27 ).…”