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524 result(s) for "Head and Neck Neoplasms - microbiology"
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Dysbiosis of salivary microbiome and cytokines influence oral squamous cell carcinoma through inflammation
Advanced combinatorial treatments of surgery, chemotherapy, and radiotherapy do not have any effect on the enhancement of a 5-year survival rate of oral squamous cell carcinoma (OSCC). The discovery of early diagnostic non-invasive biomarkers is required to improve the survival rate of OSCC patients. Recently, it has been reported that oral microbiome has a significant contribution to the development of OSCC. Oral microbiome induces inflammatory response through the production of cytokines and chemokines that enhances tumor cell proliferation and survival. The study aims to develop saliva-based oral microbiome and cytokine biomarker panel that screen OSCC patients based on the level of the microbiome and cytokine differences. We compared the oral microbiome signatures and cytokine level in the saliva of OSCC patients and healthy individuals by 16S rRNA gene sequencing targeting the V3/V4 region using the MiSeq platform and cytokine assay, respectively. The higher abundance of Prevotella melaninogenica, Fusobacterium sp., Veillonella parvula, Porphyromonas endodontalis, Prevotella pallens, Dialister, Streptococcus anginosus, Prevotella nigrescens, Campylobacter ureolyticus, Prevotella nanceiensis, Peptostreptococcus anaerobius and significant elevation of IL-8, IL-6, TNF-α, GM-CSF, and IFN-γ in the saliva of patients having OSCC. Oncobacteria such as S. anginosus, V. parvula, P. endodontalis, and P. anaerobius may contribute to the development of OSCC by increasing inflammation via increased expression of inflammatory cytokines such as IL-6, IL-8, TNF-α, IFN-γ, and GM-CSF. These oncobacteria and cytokines panels could potentially be used as a non-invasive biomarker in clinical practice for more efficient screening and early detection of OSCC patients.
A dysbiotic microbiome promotes head and neck squamous cell carcinoma
Recent studies have reported dysbiotic oral microbiota and tumor-resident bacteria in human head and neck squamous cell carcinoma (HNSCC). We aimed to identify and validate oral microbial signatures in treatment-naïve HNSCC patients compared with healthy control subjects. We confirm earlier reports that the relative abundances of Lactobacillus spp . and Neisseria spp . are elevated and diminished, respectively, in human HNSCC. In parallel, we examined the disease-modifying effects of microbiota in HNSCC, through both antibiotic depletion of microbiota in an induced HNSCC mouse model (4-Nitroquinoline 1-oxide, 4NQO) and reconstitution of tumor-associated microbiota in a germ-free orthotopic mouse model. We demonstrate that depletion of microbiota delays oral tumorigenesis, while microbiota transfer from mice with oral cancer accelerates tumorigenesis. Enrichment of Lactobacillus spp . was also observed in murine HNSCC, and activation of the aryl-hydrocarbon receptor was documented in both murine and human tumors. Together, our findings support the hypothesis that dysbiosis promotes HNSCC development.
Dysbiotic oral microbiota-derived kynurenine, induced by chronic restraint stress, promotes head and neck squamous cell carcinoma by enhancing CD8+ T cell exhaustion
BackgroundChronic restraint stress (CRS) is a tumour-promoting factor. However, the underlying mechanism is unknown.ObjectiveWe aimed to investigate whether CRS promotes head and neck squamous cell carcinoma (HNSCC) by altering the oral microbiota and related metabolites and whether kynurenine (Kyn) promotes HNSCC by modulating CD8+ T cells.Design4-nitroquinoline-1-oxide (4NQO)-treated mice were exposed to CRS. Germ-free mice treated with 4NQO received oral microbiota transplants from either CRS or control mouse donors. 16S rRNA gene sequencing and liquid chromatography-mass spectrometry were performed on mouse saliva, faecal and plasma samples to investigate alterations in their microbiota and metabolites. The effects of Kyn on HNSCC were studied using the 4NQO-induced HNSCC mouse model.ResultsMice subjected to CRS demonstrated a higher incidence of HNSCC and oral microbial dysbiosis than CRS-free control mice. Pseudomonas and Veillonella species were enriched while certain oral bacteria, including Corynebacterium and Staphylococcus species, were depleted with CRS exposure. Furthermore, CRS-altered oral microbiota promoted HNSCC formation, caused oral and gut barrier dysfunction, and induced a host metabolome shift with increased plasma Kyn in germ-free mice exposed to 4NQO treatment. Under stress conditions, we also found that Kyn activated aryl hydrocarbon receptor (AhR) nuclear translocation and deubiquitination in tumour-reactive CD8+ T cells, thereby promoting HNSCC tumourigenesis.ConclusionCRS-induced oral microbiota dysbiosis plays a protumourigenic role in HNSCC and can influence host metabolism. Mechanistically, under stress conditions, Kyn promotes CD8+ T cell exhaustion and HNSCC tumourigenesis through stabilising AhR by its deubiquitination.
Oral microbiome associated with lymph node metastasis in oral squamous cell carcinoma
Oral microbiota can alter cancer susceptibility and progression by modulating metabolism and inflammation. We assessed the association between the oral microbiome and lymph node (LN) metastasis in oral squamous cell carcinoma (OSCC). We collected a total of 54 saliva samples from patients with OSCC before surgery. LN metastasis was assessed based on postoperative pathological examination. We used QIIME2, linear discriminant analysis effect size (LEfSe), and PICRUSt2 methods to analyze microbial dysbiosis. A random forest classifier was used to assess whether the oral microbiome could predict LN metastasis. Among the 54 OSCC samples, 20 had LN metastasis, and 34 had no evidence of metastasis. There was a significant difference in β-diversity between the metastasis and no metastasis groups. Through LEfSe analysis, the metastasis group was enriched in the genera Prevotella, Stomatobaculum, Bifidobacterium, Peptostreptococcaceae, Shuttleworthia and Finegoldia. Pathways related to signal peptidase II were predominant in the no metastasis group. The RF model showed a modestly high accuracy for predicting metastasis. Differences in microbial community composition and functions were observed in the oral microbiome of patients with OSCC with and without LN metastasis. However, the finding that specific taxa may be associated with LN metastasis should be verified in a further prospective study.
Beyond Head and Neck Cancer: The Relationship Between Oral Microbiota and Tumour Development in Distant Organs
An altered oral microbiota has been linked with the development of several oral diseases, such as dental caries, periodontal disease, and oral stomatitis. Moreover, poor oral health has been linked to head and neck cancer, particularly oral cancer. In recent years a growing number of studies indicate that oral microbiota could be involved in the development of primary tumours outside of head and neck region. The aim of this article is to review the recent studies based on high-throughput technology to present evidences of a relationship between oral microbiota and \"non-head and neck tumours.\" Oral dysbiosis seem to be more pronounced in patients with tumours of gastrointestinal tract, in particular oesophageal, gastric, pancreatic, and colorectal cancers, paving the way for developing specific oral microbiota test to allow early cancer detection. Regarding other tumour types, the results are promising but highly preliminary and still debated. Currently, there are several factors that limit the generalization of the results, such as the small sample size, the lack of adequate clinical information about patients, the different sequencing techniques used, and biological sample heterogeneity. Although only at the beginning, the analysis of oral microbiota could be the next step in the evolution of cancer therapy and will help clinicians to develop individualised approaches to cancer prevention and treatment.
Microbial Communities Associated with Primary and Metastatic Head and Neck Squamous Cell Carcinoma – A High Fusobacterial and Low Streptococcal Signature
Given the potential relationship between head and neck squamous cell carcinoma (HNSCC) and microbial dysbiosis, we profiled the microbiome within healthy normal and tumorous (primary and metastatic) human tissues from the oral cavity, larynx-pharynx, and lymph nodes using 16S rRNA sequencing. Alpha and beta diversity analyses revealed that normal tissues had the greatest richness in community diversity, while the metastatic populations were most closely related to one another. Compared to the normal, the microbiota associated with tumors supported altered abundances in the phyla Fusobacteria , Firmicutes , Actinobacteria and Proteobacteria . Most notably, the relative abundance of Fusobacterium increased whereas Streptococcus decreased in both primary and metastatic samples. Principal coordinate analysis indicated a separation and clustering of samples by tissue status. However, random forest analysis revealed that the microbial profiles alone were a poor predictor for primary and metastatic HNSCC samples. Here, we report that the microbial communities residing in the tumorous tissues are compositionally distinct compared to the normal adjacent tissues. However, likely due to the smaller sample size and sample-to-sample heterogeneity, our prediction models were not able to distinguish by sample types. This work provides a foundation for future studies aimed at understanding the role of the dysbiotic tissue microbiome in HNSCC.
A comparison between full-length 16S rRNA Oxford nanopore sequencing and Illumina V3-V4 16S rRNA sequencing in head and neck cancer tissues
Describing the microbial community within the tumour has been a key aspect in understanding the pathophysiology of the tumour microenvironment. In head and neck cancer (HNC), most studies on tissue samples have only performed 16S rRNA short-read sequencing (SRS) on V3-V5 region. SRS is mostly limited to genus level identification. In this study, we compared full-length 16S rRNA long-read sequencing (FL-ONT) from Oxford Nanopore Technology (ONT) to V3-V4 Illumina SRS (V3V4-Illumina) in 26 HNC tumour tissues. Further validation was also performed using culture-based methods in 16 bacterial isolates obtained from 4 patients using MALDI-TOF MS. We observed similar alpha diversity indexes between FL-ONT and V3V4-Illumina. However, beta-diversity was significantly different between techniques (PERMANOVA - R2 = 0.131, p < 0.0001). At higher taxonomic levels (Phylum to Family), all metrics were more similar among sequencing techniques, while lower taxonomy displayed more discrepancies. At higher taxonomic levels, correlation in relative abundance from FL-ONT and V3V4-Illumina were higher, while this correlation decreased at lower levels. Finally, FL-ONT was able to identify more isolates at the species level that were identified using MALDI-TOF MS (75% vs. 18.8%). FL-ONT was able to identify lower taxonomic levels at a better resolution as compared to V3V4-Illumina 16S rRNA sequencing.
Assessing the oral microbiome of head and neck cancer patients before and during radiotherapy
Objective To characterize the oral microbiome of patients with head and neck squamous cell carcinoma (HNSCC) before and during radiotherapy (RT), compared to healthy individuals. Evaluating the impact of oral microbiome in the clinical outcomes one year following the end of RT. Methods Oral samples were collected from HNSCC patients who underwent RT using the following regimens: no dose received (T0), dose 12—16 Gy (T1), dose 30—36 Gy (T2) and dose ≥ 60 Gy (T3). Samples from healthy individuals were also collected only once as a control group. Regions V1-V2 of the 16S rRNA were sequenced by Illumina and analyzed using Mothur. Results 49 patients with HNSCC and 25 healthy individuals were included. At T0, HNSCC patients showed a lower abundance of Firmicutes and Streptococcus ( p  = 0.011, p  = 0.002) and a higher abundance of Bacteroidetes ( p  = 0.005) compared to healthy individuals. During RT, Fusobacterium ( p  = 0.017) and Porphyromonas ( p  = 0.0008) decreased, while Streptococcus increased at T1 ( p  = 0.001). By T3, the differences in Firmicutes, Bacteroidetes, and Streptococcus between the control and HNSCC groups were no longer significant ( p  > 0.3). Patients with higher initial abundances of Porphyromonas ( p  = 0.012) and Fusobacterium ( p  = 0.017) had poorer outcomes, including recurrence, metastasis, and death. In contrast, disease-free patients had a higher abundance of Streptococcus ( p  = 0.004). Conclusion Oral microbiome dysbiosis was found in HNSCC patients. By the end of RT, the main initial differences in phylum and genus abundance observed at T0 between the control and HNSCC groups were no longer present. Higher abundances of Fusobacterium and Porphyromonas were associated with poor outcomes.
Evaluation of A. actinomycetemcomitans and P. gingivalis from the mouth of patients irradiated in the head and neck region: a cross-sectional study
Purpose This study aimed to quantify Aggregatibacter actinomycetemcomitans ( A.a ) and Porphyromonas gingivalis ( P.g ) from the mouth of head and neck irradiated and cancer-free patients. Methods Information such as age, presence of tongue coating, salivary flow, and biofilm were collected from head and neck irradiated patients (Group 1) and compared the results with a group of cancer-free individuals (Group 2). The presence of tongue coating was clinically examined. Sialometry was performed through a stimulating technique by chewing paraffin. Microbiological samples were collected from buccal and labial mucosa and tongue dorsum. Subsequently, the samples were processed and analyzed by qPCR to detect the presence and quantify the bacteria. Results There was a statistical difference in the quantity of bacteria among the 24 individuals in Group 1 ( A.a , 2817 ± 8718; P.g , 3145 ± 11297) and 26 individuals in Group 2 ( A.a , 133996 ± 398545; P.g , 60 ± 195) regarding tongue coating (Group 1, A.a 2194.6 ± 4641.5; Group 2, A.a 92767.8 ± 333385.7) and salivary volume (Group 1, 0.69 mL; Group 2, 3.09 mL). The linear regression analysis found that the variable group was the main responsible for the difference in the quantity of periodontal pathogens ( p -value < 0.001). There was no statistical difference in the amount of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis between totally edentulous and partially edentulous (with 12 or fewer teeth) patients. Conclusion Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were present in significant amounts in patients of both groups, with a greater quantity in cancer-free individuals.
Bacterial Diversity Correlates with Overall Survival in Cancers of the Head and Neck, Liver, and Stomach
One in five cancers is attributed to infectious agents, and the extent of the impact on the initiation, progression, and disease outcomes may be underestimated. Infection-associated cancers are commonly attributed to viral, and to a lesser extent, parasitic and bacterial etiologies. There is growing evidence that microbial community variation rather than a single agent can influence cancer development, progression, response to therapy, and outcome. We evaluated microbial sequences from a subset of infection-associated cancers—namely, head and neck squamous cell carcinoma (HNSC), liver hepatocellular carcinoma (LIHC), and stomach adenocarcinoma (STAD) from The Cancer Genome Atlas (TCGA). A total of 470 paired tumor and adjacent normal samples were analyzed. In STAD, concurrent presence of EBV and Selemonas sputigena with a high diversity index were associated with poorer survival (HR: 2.23, 95% CI 1.26–3.94, p = 0.006 and HR: 2.31, 95% CI 1.1–4.9, p = 0.03, respectively). In LIHC, lower microbial diversity was associated with poorer overall survival (HR: 2.57, 95% CI: 1.2, 5.5, p = 0.14). Bacterial within-sample diversity correlates with overall survival in infection-associated cancers in a subset of TCGA cohorts.