Higher prevalence and gene amplification of HPV16 in oropharynx as compared to oral cavity

Prevalence of oral Epstein-Barr virus and Porphyromonas gingivalis and their association with periodontal inflamed surface area: A cross-sectional study

We previously reported that oral herpesviruses, such as Epstein-Barr virus (EBV), are associated with periodontitis. However, the relationship between oral EBV or dual oral EBV and Porphyromonas gingivalis infections and periodontal inflammation severity remains unclear. We conducted this study to determine the relationship between oral EBV and P gingivalis prevalence and the periodontal inflamed surface area (PISA) in middle-aged and older adults. We analyzed 205 patients (median age, 70 years) who visited Hiroshima University Hospital. Tongue swab samples were used to investigate the presence of EBV and P gingivalis DNA using real-time PCR. Probing pocket depth and bleeding on probing were measured at 6 sites per tooth. PISA scores were calculated based on the results of probing pocket depth and bleeding on probing. Propensity scores were calculated via logistic regression analysis of 8 clinical factors: age, sex, smoking status, remaining teeth, denture use, hypertension, diabetes, and hyperlipidemia. EBV DNA was present in 41 of the 205 participants (20.0%). Thirty-seven EBV-positive or -negative participants in 74 matched pairs after propensity-score matching were examined via univariate analysis. EBV-positive participants exhibited higher plaque control record scores and PISAs than did EBV-negative participants. EBV DNA was significantly associated with plaque control record scores and PISA (both P = .04). Of the 205 participants, 111 were positive for P gingivalis (54.1%). Nineteen participants (9.3%) were infected with both oral EBV and P gingivalis. Logistic regression analysis revealed that dual infection with EBV and P gingivalis was significantly associated with diabetes (odds ratio = 3.37, 95% confidence interval: 1.13-10.1; P = .03). Oral EBV prevalence is associated with oral hygiene and the spread of inflamed periodontal tissue. Diabetes may be a risk factor for dual infection with oral EBV and P gingivalis.

Association of oral Epstein-Barr virus with periodontal health in Japanese adults

Previous studies have demonstrated that oral Epstein-Barr virus (EBV) is associated with periodontitis. However, the relationship between periodontitis and oral EBV has not been fully elucidated by reducing the effects of confounding factors. The aim of the present study was to clarify the association between oral Epstein-Barr virus (EBV) and oral health status among middle-aged and older Japanese individuals. A total of 124 patients (46 males and 78 females; mean age, 69.2 years; age range, 35-90 years) who visited Hiroshima University Hospital between October 2018 and December 2019 were recruited into the present study. EBV DNA positivity was determined in 124 oral rinse samples using quantitative PCR. Periodontal disease-related bacteria were also detected by PCR analysis. EBV DNA was determined as positive in 16 of the 124 enrolled patients (12.9%). No significant difference was identified between EBV DNA and clinical factors (sex, age, remaining teeth, denture use, smoking or medical history). Of the 38 patients with periodontal pockets ≥6 mm, 10 were EBV DNA positive (26.3%). There was a significant association between EBV DNA positivity and probing depth (P=0.01). Additionally, a significant association was identified between bleeding on probing (BOP) and EBV DNA positivity (P=0.03). To investigate the relationship between EBV and periodontal health status, propensity score-matching was determined between participants without ≥4 mm periodontal pockets and BOP (participants with good periodontal health) and those with ≥4 mm periodontal pockets, BOP or both (participants with poor periodontal health). A total of 35 matched pairs were identified among the patients. Patients with poor periodontal health exhibited a higher EBV DNA positivity rate (25.7%) than those with good periodontal health (0.0%). Additionally, there was a significant association between EBV DNA positivity and periodontal health status (P=0.001). T. denticola-positive participants exhibited a higher EBV DNA positivity rate than negative participants (17.6 vs. 9.6%). However, there was no significant difference. The results indicated that oral EBV may be markedly associated with periodontitis in middle-aged and older Japanese individuals.

Association of oral HPV16 infection with periodontal inflammation and the oral microbiome in older women

The present preliminary study aimed to investigate the association between oral human papillomavirus type 16 (HPV16) DNA prevalence and periodontal inflammation in older women. The association between oral HPV16 infection and oral health status has not been fully elucidated in older Japanese women. The present study investigated older women aged ≥60 years who visited Hiroshima University Hospital. The present study excluded subjects with clinical factors affecting HPV infection, such as current smoking, oral cancer and pre-malignant lesions, and immunodeficiency. Finally, 46 female patients (mean age, 74.6 years) were analyzed. Quantitative PCR analysis was performed to detect HPV16 DNA in oral rinse samples. A total of 4 participants (8.7%) were HPV16 DNA positive. There was a significant association between the HPV16 DNA positivity rate and bleeding on probing (P=0.03). Additionally, Prevotella intermedia positive cases exhibited a significantly higher HPV16 DNA positivity rate than negative cases (33.3 vs 3.8%). Furthermore, analysis of 16S ribosomal RNA in bacterial flora was performed to examine microbiome diversity in participants with ≥6 mm periodontal pockets and bleeding on probing. Importantly, the average percentage of Porphyromonas was significantly higher in HPV16 DNA positive cases compared with in HPV16 DNA negative cases (5.57 vs. 1.44%). By contrast, the average percentage of Veillonella was significantly lower in HPV16 DNA positive cases than in HPV16 DNA negative cases (2.43 vs. 8.51%). Prevotella was also lower in HPV16 DNA positive cases than in HPV16 DNA negative cases (4.0 vs. 8.23%). These results indicated that people with both deep periodontal pocket inflammation and oral HPV16 infection may not have Prevotella- or Veillonella-dominant oral microbiomes, and their microbiomes may exhibit their own distinctive characteristics. In conclusion, the results suggested that oral HPV16 infection may be associated with periodontal inflammation in older Japanese women. Further research is required to clarify the detailed association between oral HPV infection and the oral microbiome.

Oral human cytomegalovirus prevalence and its relationships with periodontitis and Porphyromonas gingivalis in Japanese adults: a cross-sectional study

OBJECTIVE

This study aimed to clarify the association between oral human cytomegalovirus (HCMV) and periodontitis in Japanese adults.

METHODOLOGY

In total, 190 patients (75 men and 115 women; mean age, 70.2 years) who visited Hiroshima University Hospital between March 2018 and May 2020 were included. Oral rinse samples were taken to examine the presence of HCMV DNA using real-time polymerase chain reaction (PCR). P. gingivalis was detected by semi-quantitative PCR analysis.

RESULTS

HCMV DNA was present in nine of 190 patients (4.7%). There were significant associations between HCMV presence and the presence of ≥4-mm-deep periodontal pockets with bleeding on probing (BOP) (P<0.01) and ≥6-mm-deep periodontal pockets with BOP (P=0.01). However, no significant relationship was observed between HCMV presence and periodontal epithelial surface area scores. Logistic regression analysis revealed that the presence of ≥4-mm-deep periodontal pockets with BOP was significantly associated with HCMV (odds ratio, 14.4; P=0.01). Propensity score matching was performed between patients presenting ≥4-mm-deep periodontal pockets with BOP (i.e., active periodontitis) and patients without ≥4-mm-deep periodontal pockets with BOP; 62 matched pairs were generated. Patients who had ≥4-mm-deep periodontal pockets with BOP showed a higher rate of HCMV presence (9.7%) than those who lacked ≥4-mm-deep periodontal pockets with BOP (0.0%). There was a significant relationship between HCMV presence and ≥4-mm-deep periodontal pockets with BOP (P=0.03). A significant relationship was found between HCMV/P. gingivalis DNA presence and ≥4-mm-deep periodontal pockets with BOP (P=0.03).

CONCLUSIONS

Coinfection of oral HCMV and P. gingivalis was significantly associated with active periodontitis. Moreover, interactions between oral HCMV and P. gingivalis may be related to the severity of periodontal disease.

Human papillomavirus type 16 (HPV16) DNA copy number in oral rinse samples from oral cavity cancer patients

Objectives:

The objective of this study is to examine the human papillomavirus type 16 (HPV16) DNA copy number in the oral cavity of cancer patients using oral rinse samples.

Methods:

We analyzed the HPV16 DNA copy number of oral rinse samples in 13 primary oral cavity cancer patients (mean age 67.8 years, range 48–84 years) who visited the Department of Oral and Maxillofacial Reconstructive Surgery of Hiroshima University Hospital (Hiroshima, Japan). The 13 oral cavity cancers included 6 carcinomas in situ and 7 squamous cell carcinomas. Real-time PCR analysis was performed to examine the number of HPV16 E6 viral copies in oral rinse samples. Additionally, the HPV16 integration status was investigated using the real-time PCR findings for HPV16 E2 genes in HPV16 E6-positive oral rinse samples.

Results:

HPV16 E6 copy numbers above the detection limit in a standard curve for HPV16 E6 DNA were assessed as HPV16 positive in oral rinse samples from 6 of 13 patients. The average number of HPV16 E6 viral copies was 1.71 ± 1.72 per cell (range, 0.39–4.96 copies/cell) in six oral rinse samples. The HPV16 E2 viral load was detected in four of the six HPV16-positive oral rinse samples. Two of the six HPV16-positive oral rinse samples showed HPV16 E2 copy numbers below the detection limit, indicating the full integration of HPV16 DNA.

Conclusions:

The number of patients in this study was small; therefore, further investigation using a larger number of participants is required to clarify the level of HPV16 viral copy number in the oral cavity of cancer patients.

Endogenous Retrovirus 3 - History, Physiology, and Pathology

Endogenous viral elements (EVE) seem to be present in all eukaryotic genomes. The composition of EVE varies between different species. The endogenous retrovirus 3 (ERV3) is one of these elements that is present only in humans and other Catarrhini. Conservation of ERV3 in most of the investigated Catarrhini and the expression pattern in normal tissues suggest a putative physiological role of ERV3. On the other hand, ERV3 has been implicated in the pathogenesis of auto-immunity and cancer. In the present review we summarize knowledge about this interesting EVE. We propose the model that expression of ERV3 (and probably other EVE loci) under pathological conditions might be part of a metazoan SOS response.

High HPV16 E6 viral load in the oral cavity is associated with an increased number of bacteria: A preliminary study

In a previous study, the present research group reported that males had a significantly higher prevalence of human papillomavirus (HPV)16 than females in oral rinse samples. The objective of the present study was to examine the relationship between HPV16 viral load and clinical factors, including remaining teeth, denture use and numbers of oral bacteria. A total of 124 patients (48 males and 76 females; mean age, 61.6 years; age range, 20-97 years) who visited the Department of Oral and Maxillofacial Reconstructive Surgery of Hiroshima University Hospital (Hiroshima, Japan) between November 2016 and August 2017 were analyzed. None of the patients had evidence of oral cancer or pre-malignant lesions, including epithelial dysplasia and leukoplakia. Quantitative polymerase chain reaction (qPCR) analysis was employed to examine the number of HPV16 viral copies. Furthermore, the number of oral bacteria was determined using the dielectrophoretic impedance measurement method. HPV16 was below the limit of detection in qPCR findings for samples obtained from 30 of the 124 subjects, thus the association of HPV16 viral copy number with clinical parameters was examined in the remaining 94 patients. The average number of HPV16 E6 DNA copies was 1.65±3.47 copies/cell (range, 0.07-25.3 copies/cell) and was significantly higher in subjects with a high oral bacteria count [≥10^6.5 colony forming unit (CFU)/ml] than in those with a low count (<10^6.5 CFU/ml) (0.79±0.98 vs. 2.06±4.11 copies/cell; P=0.030). The present results indicated that HPV16 viral load may be related to an increased bacterial number in the oral cavity. Further investigations are required to clarify the correlation between oral HPV load and oral hygiene status.