The Association Between Periodontal Disease and Breast Cancer in a Prospective Cohort Study

The oral-gut microbiome axis in breast cancer: from basic research to therapeutic applications

As a complicated and heterogeneous condition, breast cancer (BC) has posed a tremendous public health challenge across the world. Recent studies have uncovered the crucial effect of human microbiota on various perspectives of health and disease, which include cancer. The oral-gut microbiome axis, particularly, have been implicated in the occurrence and development of colorectal cancer through their intricate interactions with host immune system and modulation of systemic inflammation. However, the research concerning the impact of oral-gut microbiome axis on BC remains scarce. This study focused on comprehensively reviewing and summarizing the latest ideas about the potential bidirectional relation of the gut with oral microbiota in BC, emphasizing their potential impact on tumorigenesis, treatment response, and overall patient outcomes. This review can reveal the prospect of tumor microecology and propose a novel viewpoint that the oral-gut microbiome axis can be a breakthrough point in future BC studies.

Epidemiological associations between periodontitis and cancer

There is a postulated association of periodontitis with a number of human cancers. This narrative review provides current epidemiological evidence on the association between periodontitis and cancer. A PubMed search with the relevant keywords (periodontal disease, periodontitis, cancer, and malignancy) was completed to identify relevent articles. We present a narrative review on the association between periodontal disease and a range of cancers, including oral cancer, stomach and esophageal cancer, colorectal cancer, lung cancer, pancreatic cancer, prostate cancer, hematological malignancies, liver cancer, breast cancer, and ovarian cancer. While there is a considerable body of epidemiological evidence that supports the association between periodontal disease and cancer, this is largely from cohort and case-control studies and the association may therefore be circumstantial as little evidence exists in the form of treatment trials that would validate the role of periodontal disease in the process of cancer initiation and development.

The relationship between periodontal disease and cancer: Insights from a Systematic Literature Network Analysis

This paper investigates the relationship between periodontal disease and various cancer types. It provides a comprehensive overview of the existing knowledge about the interaction between periodontal disease and carcinogenesis, explores the underlying biological mechanisms of this connection, and consider the impact of these findings on healthcare practices and future research directions. Utilizing Systematic Literature Network Analysis, which combines bibliometric analysis with Systematic Literature Review, this study analyzes 164 documents from 2000 to 2023. Focus is placed on the 38 most globally cited papers, enabling a targeted and comprehensive analysis of the predominant research within this scope. This review highlights that colorectal, oral, pancreatic, lung, and gastrointestinal cancers have consistent associations with periodontal disease. On the other hand, hematological, breast and prostate cancers show associations with periodontal disease, but these links are less pronounced and more variable, indicating the need for targeted research in these domains. These insights emphasize the necessity for a multidisciplinary healthcare approach, recognizing the systemic implications of periodontal disease.

Alveolar bone loss and tooth loss contribute to increase in cancer mortality among older patients

BACKGROUND

Both cancer and periodontitis are more prevalent with age. Information on their relationship in older patients is limited. This study aims to examine whether periodontitis is associated with increased risk of cancer mortality with a ≥ 75-year age group cohort.

METHODS

A retrospective cohort study was conducted on 1146 patients who had digital radiographic examinations. Alveolar bone loss and loss of teeth were measured as indicators of periodontitis. Hazard ratio (HR) with 95% confidence interval (CI) were taken as the effect size to summarize the associations between periodontitis and risks of cancer mortality using the multivariate adjusted cox proportional hazards model and competing risk hazard model.

RESULTS

Totally, 104 total cancer, 28 lip, oral cavity and pharynx (LOP) cancer, 39 digestive cancer and 13 respiratory cancer cases were documented over 10 years of follow-up. Total cancer (HR 1.27, 95% CI 1.06-1.53) displayed statistically significant associations with alveolar bone loss and tooth loss after adjusting for relevant confounding variables. We also observed borderline significant association between alveolar bone loss and LOP cancer (HR 1.45, 95% CI 0.99-2.12). The above associations were consistent with the results observed from the competing risk hazard models.

CONCLUSION

Our results indicate that older patients suffering from tooth loss or alveolar bone loss are at increased risks of cancer mortality, especially for total cancer and LOP cancer.

The association between poor oral health and risk of breast cancer in the UK Biobank

PURPOSE

Specific oral health conditions may be risk factors for breast cancer. This study aimed to investigate the associations of oral health conditions with breast cancer risk.

METHODS

A total of 234,363 women from the UK Biobank prospective cohort were included in this study. We examined the association of self-reported painful/bleeding gums, loose teeth, mouth ulcers, toothache, and use of dentures with the risk of breast cancer. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the associations were calculated with adjustment for multiple confounders.

RESULTS

No associations of self-reported painful/bleeding gums (HR = 1.04, 95% CI 0.98-1.10), loose teeth (HR = 0.92, 95% CI 0.82-1.02), mouth ulcers (HR = 0.99, 95% CI 0.93-1.06), toothache (HR = 1.03, 95% CI 0.92-1.14), or denture use (HR = 0.96, 95% CI 0.91-1.02) with breast cancer risk were found. No statistical heterogeneity was observed in analyses stratified by baseline smoking and menopausal status.

CONCLUSION

We observed no association between self-reported oral health conditions with the risk of breast cancer. Additional research with clinical examinations or oral health biomarkers in diverse populations is warranted.

Association between periodontitis and breast cancer: two-sample Mendelian randomization study

OBJECTIVES

The purpose of this study was to investigate whether there is a causal relationship between periodontitis and breast cancer by Mendelian randomization analysis.

MATERIALS AND METHODS

We performed a two-sample bidirectional Mendelian randomization (MR) analysis using publicly released genome-wide association studies (GWAS) statistics. The inverse-variance weighted (IVW) method was used as the primary analysis. We applied complementary methods, including weighted median, weighted mode, simple mode, MR-Egger regression, and MR-pleiotropy residual sum and outlier (MR-PRESSO) to detect and correct for the effect of horizontal pleiotropy.

RESULTS

IVW MR analysis showed no effect of periodontitis on breast cancer (IVW OR=0.99, P =0.14). Similarly, no significant causal relationship between breast cancer and periodontitis was found in reverse MR analysis (IVW OR=0.95, P =0.83). The results of MR-Egger regression, weighted median, and weighted mode methods were consistent with those of the IVW method. Based on sensitivity analyses, horizontal pleiotropy is unlikely to distort causal estimates.

CONCLUSIONS

Although observational studies have reported an association between periodontitis and breast cancer, the results of our MR analysis do not support a causal relationship between periodontitis and breast cancer.

CLINICAL RELEVANCE

Mendelian randomization study can more clearly analyze the causal relationship between periodontitis and breast cancer, in order to provide a certain reference for clinicians and deepen the understanding of the relationship between periodontitis and breast cancer, to explore more possible associations between periodontitis and systemic diseases.

The Relationship Between Periodontal Disease and Breast Cancer: From Basic Mechanism to Clinical Management and Prevention

PURPOSE

Periodontal disease is potentially related to certain kinds of cancer. This review aimed to summarize the relationship between periodontal disease and breast cancer, providing some strategies for the clinical treatment and periodontal health care of breast cancer patients.

MATERIALS AND METHODS

Systematic reviews, randomised controlled trials, prospective and retrospective clinical studies, case series and reports were collected using search terms entered into the PubMed, Google Scholar and JSTOR databases.

RESULTS

Research has provided some evidence that periodontal disease is related to the occurrence and development of breast cancer. Periodontal disease and breast cancer have some common pathogenic factors. Periodontal disease may affect the initiation and development of breast cancer involving microorganisms and inflammation. Periodontal health is affected by radiotherapy, chemotherapy, and endocrine therapy for breast cancer.

CONCLUSIONS

Periodontal therapy for breast cancer patients should be performed differently according to the stage of cancer treatment. Adjuvant endocrine treatment (e.g. bisphosphonates) has a great impact on oral treatment. Periodontal therapy contributes to the primary prevention of breast cancer. Periodontal health care of breast cancer patients is worthy of clinician attention.

The oral microbiome and breast cancer and nonmalignant breast disease, and its relationship with the fecal microbiome in the Ghana Breast Health Study

The oral microbiome, like the fecal microbiome, may be related to breast cancer risk. Therefore, we investigated whether the oral microbiome was associated with breast cancer and nonmalignant breast disease, and its relationship with the fecal microbiome in a case-control study in Ghana. A total of 881 women were included (369 breast cancers, 93 nonmalignant cases and 419 population-based controls). The V4 region of the 16S rRNA gene was sequenced from oral and fecal samples. Alpha-diversity (observed amplicon sequence variants [ASVs], Shannon index and Faith's Phylogenetic Diversity) and beta-diversity (Bray-Curtis, Jaccard and weighted and unweighted UniFrac) metrics were computed. MiRKAT and logistic regression models were used to investigate the case-control associations. Oral sample alpha-diversity was inversely associated with breast cancer and nonmalignant breast disease with odds ratios (95% CIs) per every 10 observed ASVs of 0.86 (0.83-0.89) and 0.79 (0.73-0.85), respectively, compared to controls. Beta-diversity was also associated with breast cancer and nonmalignant breast disease compared to controls (P ≤ .001). The relative abundances of Porphyromonas and Fusobacterium were lower for breast cancer cases compared to controls. Alpha-diversity and presence/relative abundance of specific genera from the oral and fecal microbiome were strongly correlated among breast cancer cases, but weakly correlated among controls. Particularly, the relative abundance of oral Porphyromonas was strongly, inversely correlated with fecal Bacteroides among breast cancer cases (r = -.37, P ≤ .001). Many oral microbial metrics were strongly associated with breast cancer and nonmalignant breast disease, and strongly correlated with fecal microbiome among breast cancer cases, but not controls.

Associations of periodontal disease and tooth loss with all-cause and cause-specific mortality in the Sister Study

AIM

Studies have found that periodontal disease and tooth loss are associated with increased mortality; however, associations with cause-specific mortality and all-cause mortality within specific subgroups have not been thoroughly investigated.

MATERIALS AND METHODS

We examined the association of self-reported periodontal disease and disease/decay-related tooth loss with subsequent all-cause and cause-specific mortality in the Sister Study, a prospective cohort study of 50,884 women aged 35-74 years at baseline, whose sister was diagnosed with breast cancer. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the associations were calculated with adjustment for relevant confounders.

RESULTS

With a mean follow-up of 10.9 years (range 0.1-14.3), 2058 women died. Participants with periodontal disease had a slightly higher rate of all-cause mortality (HR = 1.08, 95% CI 0.98-1.19), while participants with tooth loss had an increased rate of all-cause mortality (HR = 1.15, 95% CI 1.05-1.26). For cause-specific mortality, women with tooth loss had increased rates of death from circulatory system diseases, respiratory system diseases, and endocrine/metabolic diseases. Results varied in stratified models, but no heterogeneity across strata was found.

CONCLUSIONS

In this large prospective study, periodontal disease and tooth loss were associated with all-cause and certain specific cause-specific mortality outcomes.

Periodontal Disease and Breast Cancer Risk: Results from the Nurses' Health Study

BACKGROUND

While periodontal disease has been linked to increased cancer risk, studies regarding an association with breast cancer are limited.

METHODS

We examined the relationship between self-reported diagnosis of periodontal bone loss and incidence of breast cancer in a large, prospective cohort study, the Nurses' Health Study (1998-2014). We calculated HRs using Cox proportional hazards modeling, adjusting for risk factors common to both periodontal disease and breast cancer.

RESULTS

During 1,023,647 person-years of follow-up, 5,110 of breast cancer cases were reported. We observed no association between periodontal disease and overall breast cancer risk (HR, 1.02; 95% confidence interval: 0.94-1.10); the association was not modified by smoking status, or other breast cancer risk factors or by breast tumor subtypes.

CONCLUSIONS

We did not observe any association between periodontal disease and breast cancer risk.

IMPACT

Given inconsistent findings in the literature, further research with standardized clinical measures of periodontitis is warranted.

Effects of statins on cytokines levels in gingival crevicular fluid and saliva and on clinical periodontal parameters of middle-aged and elderly patients with type 2 diabetes mellitus

Objective

To analyze the effect of statins on cytokines levels in gingival crevicular fluid (GCF) and saliva and on clinical periodontal parameters of middle-aged and elderly patients with type 2 diabetes mellitus (T2DM).

Methods

Systemically healthy controls (C group, n = 62), T2DM patients not taking statins (D group, n = 57) and T2DM patients taking statins (S group, n = 24) were recruited. In each group, subjects (40–85 years) were subclassified into the h (periodontal health)group, the g (gingivitis)group or the p (periodontitis) group according to different periodontal conditions. 17 cytokines in gingival crevicular fluid (GCF) and saliva samples of each subject were measured utilizing the Luminex technology kit. Further, HbA1c (glycated hemoglobin), FPG (fasting plasma glucose), PD (probing depth), CAL (clinical attachment level), BOP (bleeding on probing), GI (gingival index) and PI (periodontal index) were recorded. Data distribution was tested through the Shapiro-Wilk test, upon which the Kruskal-Wallis test was applied followed by Mann-Whitney U test and Bonferroni’s correction.

Results

Levels of IFN-γ, IL-5, IL-10 and IL-13 in the saliva of the Dh group were significantly lower than those in the Ch group, while factor IL-4 was higher (p<0.05). Levels of MIP-3α, IL-7 and IL-2 in GCF of the Dh group were considerably higher than those in the Ch group (p<0.05), while that of IL-23 was considerably lower. Compared with the Cg group, levels of IFN-γ, IL-4, IL-5, IL-6, IL-10 and IL-13 were significantly lower in the saliva of the Dg group (p<0.05). Lower levels of IFN-γ, IL-5 and IL-10 were detected in the Sg group than those in the Cg group (p<0.05). At the same time, levels of IL-1β, IL-6, IL-7, IL-13, IL-17, IL-21 and MIP-3α in the gingival crevicular fluid of the Sg group were lower in comparison with the Dg group. In addition, lower levels of IL-4 and higher levels of IL-7 in GCF were identified in the Dg group than those in the Cg group, while in the Sg group, lower levels of IL-4, MIP-1αand MIP-3αwere observed than those in the Cg group (p<0.05). Lower levels of IFN-γ, IL-6, IL-10, IL-13 and I-TAC were found in the Sp group compared with those in the Cp group. The IFN-γ, IL-6 and IL-10 levels were lower in the Dp group than those in the Cp group (p<0.05). Meanwhile, in the Sp group, lower levels of pro-inflammatory factors IFN-γ, IL-1β, IL-2, IL-6, IL-7, IL-21 and TNF-α, in addition to higher levels of anti-inflammatory factors IL-4 and IL-5 in gingival crevicular fluid, were identified than those in the Dp group. Higher levels of IFN-γ,IL-1β,IL-2,IL-7,IL-21 and TNF-α and a lower level of IL-5 in the Dp group were identified than those in the Cp group (p<0.05). Moreover, statins were able to substantially reduce PD in T2DM patients with periodontitis, indicating an obvious influence on the levels of cytokines secreted by Th1 cells, Th2 cells and Th17 cells, as revealed by PCA (principal component analysis).

Conclusion

Statins are associated with reduced PD and cytokines levels in the GCF and saliva of T2DM patients with periodontitis.