Breast Cancer Risk and Human Papillomavirus Infection: A Bradford Hill Criteria Based Evaluation

High rate of high-risk human papillomavirus among benign and breast cancer patients in Ethiopia

INTRODUCTION

There have been numerous studies that showed the presence of human papillomavirus (HPV) in breast cancer; nonetheless, there is ongoing debate regarding their association. Given few studies in Ethiopia, we aimed to investigate the magnitude of HPV infection in Ethiopian breast cancer patients.

METHODS

A total of 120 formalin-fixed paraffin-embedded (FFPE) tissue blocks were obtained, and basic demographic, clinical, and histological data were collected from medical records. DNA was extracted from archived FFPE breast tissue specimens using GeneRead DNA FFPE Kit. The AnyplexTM II HPV28 Detection Kit (Seegene, Korea) was used to detect HPV by following the manufacturer's instructions. The SPSS Version 25 was used to enter and analyze data.

RESULTS

Among the 120 study participants; HPV (both high-risk and low-risk) was detected in 20.6% of breast cancer and 29.6% of non-malignant breast tumors. The most common genotype was the high-risk HPV 16 genotype. The frequency of HPV was nearly 10-fold higher in estrogen receptor-positive than ER-negative breast cancer. The percentage of HPV in the luminal (luminal A and luminal B) breast cancer subtypes was also much higher than in the non-luminal subtypes (HER-2 enriched and triple-negative breast cancer).

CONCLUSION

This study did not find a significant difference in HPV expression between breast cancer and non-malignant breast tumors; however, the higher percentage of HPV in ER-positive compared to ER-negative breast cancer warrants further attention.

HPV infection and breast cancer risk: insights from a nationwide population study in Taiwan

Background

The prevalence of cancer, specifically breast cancer, has raised globally. The etiology of breast cancer has been attributed to age, genetic mutations, reproductive history, hormone therapy, lifestyle factors, and viral infections. The human papillomavirus (HPV) has been one of the most widespread sexually transmitted infection in the United States. The role of HPV in breast oncogenesis was hypothesized before, yet the association remained unclear.

Methods

In this study, we employed a nationwide population study using centralized patient data managed by the Ministry of Health and Welfare in Taiwan and the Taiwan Cancer Registry database. The breast cancer incidence rates of the 467,454 HPV patients were compared to twice as many non-HPV patients with matching sex and age. Cumulative breast cancer incidence rates were presented by a Kaplan-Meier curve, and the relative risk of breast cancer for HPV and non-HPV patients were calculated using Cox-regression model.

Results

Our results indicated a crude hazard ratio (HR) and an adjusted hazard ratio (aHR) of 2.336 and 2.271, respectively, when comparing the risk of breast cancer in the HPV and non-HPV group. The risk of breast cancer was comparable or higher than those of head and neck cancer (aHR=1.595) and cervical cancer (aHR=2.225), which both were found to have causal relationships with HPV. The Kaplan-Meier curve further illustrated a higher cumulative risk across 84 months for HPV patients (p<.0001). Besides HPV, age (p<.0001), insurance providers (p<.001), and comorbidities such as abnormal liver function (aHR=1.191, p=.0069) and hyperlipidemia (aHR=1.218, p=.0002) were found to be correlated with higher risks of breast cancer.

Conclusion

A correlation between HPV and breast cancer can be inferred using national health databases. More molecular studies are required to understand the mechanism of the virus-induced oncogenesis of the breast.

HPV-Associated Breast Cancer: Myth or Fact?

Some estimates place the proportion of human malignancies attributable to viruses at between 15 and 20 percent. Viruses including the human papillomavirus are considered an interesting but controversial etiological risk factor for breast cancer. HPV infection is anticipated to be an early trigger in breast cancer carcinogenesis, followed by cumulative alterations over time ("hit and run" mechanism) through synergy with other environmental factors. The association between HPV and breast cancer has not yet been verified. There are very conflicting data on the presence of HPV DNA in breast cancer samples, and we lack a clarified, exact mode of HPV transmission to the breast. In our review article we analyzed the up-to-date knowledge about the association of HPV and breast cancer. Furthermore, we summarized the available original research published since 2010. In conclusion, the complexity and inconsistency of the available results together with the relatively low prevalence of HPV infection requires extensive research with much larger studies and exact and unified diagnostic methods are required to better understand the role of the HPV in breast carcinogenesis.

Prevalence of cancer in relation to signs of periodontal inflammation

We investigated the associations between periodontal inflammation (gingivitis and periodontitis) and all-kind malignancies, specifically breast and prostate cancer, in a cohort followed-up for 30 years. The study hypothesis was based on the oral inflammation vs. systemic health paradigm. A sample of 2,168 subjects from an original cohort of 105,718 individuals from the greater Stockholm area in Sweden that had been followed since 1985 was investigated. Swedish national health registers were used in the study. Chi-square tests and logistic multiple regression analyses were conducted. The results showed that periodontitis was significantly associated with any cancer after adjusting for gender, age, income, and education (p = 0.015). The probability of getting cancer increased on average by 38% if the patient had periodontitis vs. had not; the odds ratio was 1.380 (95% confidence interval l.066-1.786). No significant association was observed between periodontitis and breast cancer (p = 0.608), while the association between periodontitis and prostate cancer tended towards significance (p = 0.082). However, no statistically significant difference was found between the observed and the calculated distribution of any cancer in gingivitis groups (p = 0.079). Thus, the study hypothesis was partly confirmed by showing a statistically significant association between periodontitis and any cancer.

Bioinformatics Method Was Used to Analyze the Highly Expressed Gene FAM83A of Breast Cancer in Young Women

Objectives

Preliminary analysis of breast cancer related to unknown functional gene FAM83A through bioinformatics knowledge to inform further experimental studies. Select high expression genes for breast cancer and use bioinformatics methods to predict the biological function of FAM83A.

Methods

Genes with significant differences in expression between breast tumors and normal breast tissue libraries were selected from CGAP's SAGE Digital Gene Expression Displayer (DGED) database. An unknown functional gene, FAM83A, which is highly expressed in breast cancer, was screened. We performed an analysis of the gene structure, subcellular localization, physicochemical properties of the encoding products, functional sites, protein structure, and functional domains.

Results

Through SAGE DGED, a total of 185 genes with expression differences were found. The structure and function of FAM83A have ideal predictions, and it is generally determined that this gene encodes a nuclear protein with a nucleoprotein. The active site of PLDc and the functional domain of DUF1669 can be involved in signal transduction and gene expression regulation in tumorigenesis and metastasis. Digital gene representation of the Tumor Genome Project Data Library was used to select differentially expressed genes in breast cancer tissue and breast benign tumor tissue.

Conclusion

Studies show that FAM83A is a potential research target associated with tumorigenesis and metastasis. Initial tests confirmed the expression of this gene. Lay a solid foundation for further research learning. FAM83A is a highly expressed gene in breast cancer and can serve as a target for studying molecular mechanisms in breast cancer.