Human papillomavirus type 33 DNA in breast cancer in Chinese

The viral origins of breast cancer

During the past two decades evidence has been developed that indicates a handful of viruses with known oncogenic capacity, have potential roles in breast cancer. These viruses are mouse mammary tumour virus (MMTV - the cause of breast cancer in mice), high-risk human papilloma viruses (HPV-the cause of cervical cancer), Epstein Barr virus (EBV-the cause of lymphomas and naso-pharyngeal cancer) and bovine leukemia virus (BLV - the cause of cancers in cattle). These viruses may act alone or in combination. Each of these viruses are significantly more prevalent in breast cancers than in normal and benign breast tissue controls. The odds ratios for the prevalence of these viruses in breast cancer compared to normal and benign breast controls, are based on case control studies - MMTV 13·40, HPV 5.56, EBV 4·43 and BLV 2·57. The odds ratios for MMTV are much greater compared to the other three viruses. The evidence for a causal role for mouse mammary tumour virus and high risk for cancer human papilloma viruses in human breast cancer is increasingly comprehensive. The evidence for Epstein Barr virus and bovine leukemia virus is more limited. Overall the evidence is substantial in support of a viral cause of breast cancer.

An updated systemic review and meta-analysis on human papillomavirus in breast carcinogenesis

Background

Breast Cancer (BC) stands out as the widely prevalent malignancy among all the types of cancer affecting women worldwide. There is significant evidence that the pathogenicity of BC may be altered by Human Papillomavirus (HPV) infection; however, conclusive data are not yet available.

Methods

By searching five databases, including EMBASE, IBECS, PubMed, Scopus, Science Direct, Google Scholar, and Web of Science, a thorough systematic analysis was conducted on the prevalence of HPV in BC patients from 1990 to June 30, 2022. After applying extensive eligibility criteria, we selected 74 publications for further analysis based on the prevalence of HPV infections in breast tissues. All of the data were analyzed using a random-effects meta-analysis, Cochran Q test and I2 statistic were used to calculate the heterogeneity of the prevalence among these studies using subgroup analysis. Variations in the HPV prevalence estimates in different subgroups were evaluated by subgroup meta-analysis.

Results

In total, 3156 studies were initially screened, resulting in 93 full-text studies reviewed, with 74 meeting inclusion criteria. Among a total of 7156 BC biopsies, the pool prevalence of HPV was 25.6% (95% CI= 0.24-0.33, τ2 = 0.0369 with significant heterogeneity between estimates (I 2 = 97% and p< 0.01). Consequently, 45 studies with available controls were further studied, and the prevalence of HPV in case-control studies was 26.2% with overall odds 5.55 (95% CI= 3.67-8.41, I 2 = 38%, τ2 = 1.4878, p< 0.01). Further subgroup analysis of HPV revealed HPV-16 had a maximum prevalence of 9.6% (95% CI= 3.06-11.86, I 2 = 0%, τ2 = 0.6111, p< 0.01). Among different geographical regions, Europe reported the maximum prevalence of HPV, i.e., 39.2% (95% CI=1.29-7.91, I 2 = 18%, τ2 = 1.2911, p< 0.01). Overall distribution showed HPV-18 was a frequent HPV subtype reported in Australia.

Conclusion

Current study provides a global estimate of HPV prevalence in BC patients and demonstrates a significant association between this virus and BC etiology. Nevertheless, we recommend further investigation into the underlying mechanism is essential to validate this hypothesis.

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

BACKGROUND

The association between human papillomavirus (HPV) and human breast cancer (BC) has already been thoroughly studied worldwide with contradictory findings. Although the researchers have tried to minimize the conflict using statistical meta-analysis, because of its shortcomings, there is still a need to evaluate the correlation between HPV and BC using any additional method.

OBJECTIVES

This study was launched to investigate the correlation between HPV and BC through the application of Bradford Hill criteria postulates.

METHODS

Population-wide studies associating HPV with BC were searched using the PubMed database. Then, the information of HPV burden in BC, normal/benign samples was analyzed, and ultimately Bradford Hill criteria postulates were applied on the collected evidence to explore the relationship between HPV and BC. In addition, to make the outcomes more authentic, we also reviewed the methodologies of previous studies to address the propensity of false results.

RESULTS

After a careful evaluation of the obtained data against major Bradford Hill criteria postulates, it was noted that all these postulates including strength, consistency, biological gradient, temporality, plausibility, experiment, specificity, and analogy were not fulfilled.

CONCLUSION

The results of the present study have failed to establish a casual association between HPV and BC rather suggested HPV as a cause-effective agent or at least a co-participant in the pathogenesis of BC. The weakness of association especially the low level of consistency across studies, and the lack of specificity of effect, there is a need for more experiments concerning Bradford Hill criteria postulates.

Presence of high-risk HPVs, EBV, and MMTV in human triple-negative breast cancer

Breast cancer, the most frequent disease amongst women worldwide, accounts for the highest cancer-related mortality rate. Triple-negative breast cancer (TNBC) subtype encompasses ~15% of all breast cancers and lack estrogen, progesterone, and HER2 receptors. Although risk factors for breast cancer are well-known, factors underpinning breast cancer onset and progression remain unknown. Recent studies suggest the plausible role of oncoviruses including human papillomaviruses (HPVs), Epstein-Barr virus (EBV), and mouse mammary tumor virus (MMTV) in breast cancer pathogenesis. However, the role of these oncoviruses in TNBC is still unclear. In the current study, we explored the status of high-risk HPVs, EBV, and MMTV in a well-defined TNBC cohort from Croatia in comparison to 16 normal/non TNBC samples (controls) using polymerase chain reaction assay. We found high-risk HPVs and EBV present in 37/70 (53%) and 25/70 (36%) of the cases, respectively. The most common HPV types are 52, 45, 31, 58 and 68. We found 16% of the samples positive for co-presence of high-risk HPVs and EBV. Moreover, our data revealed that 5/70 (7%) samples are positive for MMTV. In addition, only 2/70 (3%) samples had co-presence of HPVs, EBV, and MMTV without any significant association with the clinicopathological variables. While, 6/16 (37.5%) controls were positive for HPV (p = .4), EBV was absent in all controls (0/16, 0%) (p = .01). In addition, we did not find the co-presence of the oncoviruses in the controls (p > .05). Nevertheless, further investigations are essential to understand the underlying mechanisms of multiple-oncogenic viruses' interaction in breast carcinogenesis, especially TNBC.

High-risk human papillomaviruses and Epstein-Barr virus in breast cancer in Lebanese women and their association with tumor grade: a molecular and tissue microarray study

Background

High-risk human papillomaviruses (HPVs) are present and can cooperate with Epstein–Barr virus (EBV) to initiate and/or enhance the progression of several types of human carcinomas including cervical as well as head and neck; in parallel, it has been recently pointed out that these oncoviruses can be detected in human breast cancers. Thus, we herein explored the presence/co-presence of high-risk HPVs and EBV in breast cancer in Lebanese women.

Methods

A cohort of 102 breast cancer samples and 14 normal breast tissues were assessed for the presence of HPVs and EBV. Polymerase chain reaction (PCR) and immunohistochemistry (IHC) analysis in addition to tissue microarray (TMA) platform were used in this study.

Results

We found the presence of HPV in 66/102 (65%) of our samples, while EBV is present in 41/102 (40%) of the cohort. Additionally, our data showed that high-risk HPV types (52, 35, 58, 45, 16 and 51) are the most frequent in breast cancer in Lebanese women. Meanwhile, we report that high-risk HPVs and EBV are co-present in 30/102 (29%) of the samples; more significantly, our results indicate that their co-presence is associated with tumor grade (p = 0.03).

Conclusion

Our data revealed that HPVs and EBV are present/co-present in human breast cancer where they may play an important role in its development and/or progression; thus, we believe that further investigations are essential to confirm and elucidate the presence/co-presence of these oncoviruses and the underlying mechanisms of their interaction in breast carcinogenesis.

Oncoproteins of High-Risk HPV and EBV Cooperate to Enhance Cell Motility and Invasion of Human Breast Cancer Cells via Erk1/Erk2 and β-Catenin Signaling Pathways

Breast cancer is a leading cause of death in women around the world. Most breast cancer-related deaths are a result of complications from the metastatic spread. Several recent studies reported that high-risk human papillomaviruses (HPVs) and Epstein-Barr virus (EBV) are co-presented in different types of human carcinomas including breast; however, the cooperative effects between high-risk HPVs and EBV oncoproteins in human breast cancer have not been investigated yet. Thus, we herein explored the cooperation outcome between E6/E7 and latent membrane protein 1 (LMP1) oncoproteins of high-risk HPV type 16 and EBV, respectively, in two human breast cancer cell lines, MCF7 and MDA-MB-231. Our data revealed that the cooperation of E6/E7 and LMP1 oncoproteins stimulates cell proliferation and deregulates cell cycle progression of human breast cancer and normal mammary cells; in parallel, we noted that E6/E7/LMP1 incite colony formation of both breast cancer cell lines but not normal cells. More significantly, our results point out that the co-expression of E6/E7 and LMP1 oncoproteins enhances cell motility and invasion of MCF7 and MDA-MB-231 cell lines; this is accompanied by deregulation of epithelial-mesenchymal transition biomarkers including E-cadherin, β-catenin, fascin, and vimentin. The molecular pathway analysis of HPV and EBV oncoproteins cooperation shows that it can enhance the phosphorylation of extracellular signal-regulated kinases (Erk1/Erk2) in addition to β-catenin, which could be behind the effect of this cooperation in our cell models. The study clearly suggests that high-risk HPV and EBV coinfection can play an important role in breast cancer progression via Erk1/Erk2 and β-catenin signaling pathways.

Assessment of Human Papillomavirus Infection and Risk Factors in Egyptian Women With Breast Cancer

Numerous risk factors for breast cancer (BC) have been identified. High-risk human papilloma virus (HR-HPV) is the etiological agent of cervical cancer and in some cases of head and neck cancer, specifically oropharyngeal cancer, but the role of HR-HPV in evoking neoplasia in BC is still unclear. In this study, all women above the age of 18 visiting the oncology clinic at Al-Azhar university hospital and Ain Shams specialized hospital between the period of February 2017 and March 2018 were invited to participate. We determined the prevalence of HR-HPV genotypes 16, 18, and 31 in breast tissue samples from 72 women with treatment-naïve BC and 15 women with benign breast lesions (BBL) by quantitative real-time PCR (qRT-PCR) and primer sets targeting the E6 and E7 regions. High-risk human papilloma virus DNA was detected in 16 of 72 (22.2%) BC cases (viral load range = 0.3-237.8 copies/uL) and 0 of 15 women with BBL. High-risk human papilloma virus was detected in 14 of 16 (87.5%), 2 of 16 (12.5%), and 0 of 16 (0%) for genotypes 16, 18, and 31, respectively. Forty-three age-matched healthy Egyptian women were enrolled as controls for assessment of local risk factors that can be used to initiate a strategy of BC prevention in Egypt. Assessment of the risk factors demonstrated that low education level, passive smoking, lack of physical activity, family history of cancer, and use of oral contraception were significant risk factors for BC. In conclusion, our results lead us to postulate that HR-HPV infection may be implicated in the development of some types of BC in Egyptian women. In addition, identification of local risk factors can support practical prevention strategies for BC in Egypt.

Human Mammary Tumor Virus, Human Papilloma Virus, and Epstein-Barr Virus Infection Are Associated With Sporadic Breast Cancer Metastasis

Background

Viral cause of sporadic breast cancer (SBC) has been suggested based on the experimental murine model of mammary tumor caused by mouse mammary tumor virus (MMTV), Epstein-Barr virus (EBV), and human papillomavirus (HPV). While some studies have demonstrated the presence of viral sequences of MMTV, HPV, and EBV in breast cancer cells, others failed. These contradictions may be attributed to the geographical distribution of breast cancer incidence and/or technical variations. In the current study, we aimed to investigate the correlation of MMTV, HPV, and EBV infections with the development of breast cancer in Jordanian patients.

Methods

One hundred SBC tissue samples were subjected to laser capture microdissection for the selection of tumor cells populations. Fluorescence polymerase chain reaction (PCR) was used to detect the presence of the MMTV env-like sequences. Real-time PCR was used for HPV and EBV detection, and EBV was further confirmed by chromogen in situ hybridization (CISH).

Results

Mouse mammary tumor virus, HPV, and EBV were detected in SBC in 11%, 21%, and 23%, respectively. Only 3 of 52 (5.7%) positive cases demonstrated multiple virus infections. However, 49 of 52 (94%) of the positive cases revealed the presence of 1 type of viral sequences. Consequently, 52% of the studied breast cancer cases were infected with at least 1 type of the aforementioned viruses.

Conclusions

The current cohort suggests that MMTV, HPV, and EBV have a potential role in the development of breast cancer and adding more reasons to proceed with the quest of a possible viral origin of breast cancer.

Human Mammary Tumor Virus, Human Papilloma Virus, and Epstein-Barr Virus Infection Are Associated With Sporadic Breast Cancer Metastasis

Background:

Viral cause of sporadic breast cancer (SBC) has been suggested based on the experimental murine model of mammary tumor caused by mouse mammary tumor virus (MMTV), Epstein-Barr virus (EBV), and human papillomavirus (HPV). While some studies have demonstrated the presence of viral sequences of MMTV, HPV, and EBV in breast cancer cells, others failed. These contradictions may be attributed to the geographical distribution of breast cancer incidence and/or technical variations. In the current study, we aimed to investigate the correlation of MMTV, HPV, and EBV infections with the development of breast cancer in Jordanian patients.

Methods:

One hundred SBC tissue samples were subjected to laser capture microdissection for the selection of tumor cells populations. Fluorescence polymerase chain reaction (PCR) was used to detect the presence of the MMTV env-like sequences. Real-time PCR was used for HPV and EBV detection, and EBV was further confirmed by chromogen in situ hybridization (CISH).

Results:

Mouse mammary tumor virus, HPV, and EBV were detected in SBC in 11%, 21%, and 23%, respectively. Only 3 of 52 (5.7%) positive cases demonstrated multiple virus infections. However, 49 of 52 (94%) of the positive cases revealed the presence of 1 type of viral sequences. Consequently, 52% of the studied breast cancer cases were infected with at least 1 type of the aforementioned viruses.

Conclusions:

The current cohort suggests that MMTV, HPV, and EBV have a potential role in the development of breast cancer and adding more reasons to proceed with the quest of a possible viral origin of breast cancer.

The co-presence of high-risk human papillomaviruses and Epstein-Barr virus is linked with tumor grade and stage in Qatari women with breast cancer

High-risk human papillomaviruses (HPV) can be present and cooperate with Epstein–Barr virus (EBV) to promote the onset and/or progression of various cancers including cervical, breast, head and neck as well as colorectal. In this investigation, we explored the co-prevalence of high-risk HPV and EBV in 74 breast cancer tissues from Qatari women using polymerase chain reaction. We found that high-risk HPV and EBV are present in 48/74 (65%) and 36/74 (49%) of the cases, respectively. While we noted that the presence of HPV presence is associated with triple-negative breast cancer (TNBC) (p = .008), however, the presence of EBV did not correlate with any breast cancer subgroup. Moreover, our data revealed that high-risk HPV and EBV are co-present in 35/74 (47%) of the samples and their co-presence is significantly associated with tumor grade (p = .04) and tumor stage (p = .04). These data indicate that HPV and EBV are commonly co-present in breast cancer and their association could be linked with a more aggressive tumor phenotype. Thus, further investigations are essential to understand the underlying mechanisms of HPV and EBV cooperation in breast carcinogenesis.

Human papilloma virus (HPV) profiles in breast cancer: future management

Breast cancer (BC) is frequent among women in worldwide as well as in India. Several studies have reported a wide variation (1.6–86.2%) in the frequency of incidence of human papillomavirus (HPV) infection in BC with high prevalence of high risk HPV16 subtype. HPV infection in breast can occur through different routes like body fluid or by micro-lesion of breast skin from genital/agential sites, though the actual mode of HPV transmission is not yet known in details. Frequent integration and sequence variation with low copy number of HPV16 were seen in this tumour. In addition, high frequencies of methylation in p97 promoter region of HPV16 were evident in this tumour. Novel splice variants of E6/E7 along with other common variants and their protein expression were seen in the tumour. This indicates the importance of HPV in this tumor, its early diagnosis and prognosis. Thus, HPV may be targeted through vaccination to control the disease. However, detailed analysis of HPV associated molecular pathogenesis of BC is warranted for proper therapeutic intervention.

Human papilloma virus and breast cancer: the role of inflammation and viral expressed proteins

BACKGROUND

Breast cancer is currently the most common neoplasm diagnosed in women globally. There is a growing body of evidence to suggest that human papillomavirus (HPV) infection may play a key role in invasiveness of breast cancer. The aim of this study was to determine the presence of HPV in patients with breast cancer and its possible association with cancer progression.

METHODS

Breast specimens were collected from 72 patients with breast cancer and 31 healthy controls. The presence of HPV was investigated by polymerase chain reaction (PCR) and genotyping was performed for positive cases. We also evaluated the viral factors such as E6, E2, and E7 in HPV positive cases. Enzyme-linked immunosorbent assay (ELISA (and Real-time PCR techniques were used to measure the expression level of anti-carcinogenic genes, such as p53, retinoblastoma (RB), breast and ovarian cancer susceptibility gene (BRCA1, BRCA2) and inflammatory cytokines, including tumor necrosis factor α (TNF-α), transforming growth factor β (TGF-β), nuclear factor-kB (NF-kB), and different interleukins [ILs] (IL-1,IL6, and IL-17).

RESULTS

The HPV DNA was detected in 48.6% of breast cancer samples, whereas only 16.1% of controls were positive for HPV. We observed statistically significant differences between breast cancer patients and HPV presence (P = 0.003). HPV type 18 was the most prevalent virus genotype in patients. The expression of P53, RB, BRCA1, and BRCA2 were decreased in patients with HPV-positive breast cancer as compared to HPV-negative breast cancer and healthy controls. (All P-values were less than 0.05). The presence of the HPV was associated with increased inflammatory cytokines (IL-1, IL-6, IL-17, TGF-β, TNF-α, and NF-kB) and tumor progression.

CONCLUSION

The present study demonstrated that HPV infection may implicate in the development of some types of breast cancer.

Association of breast cancer with human papillomavirus (HPV) infection in Northeast Brazil: molecular evidence

OBJECTIVE

The aim of this study is to investigate the presence of human papillomavirus DNA and genotypes in breast cancer and normal breast tissue samples obtained from women from the northeast region of Brazil.

METHOD

One hundred three breast cancer samples and 95 normal breast samples, as the non-malignant controls, were studied. DNA extraction was verified by human beta-globin gene amplification, and polymerase chain reaction was conducted based on HPV L1-specific consensus primers MY09/MY11 and GP5+/GP6+, followed by nested multiplex polymerase chain reaction with type-specific primers for the E6/E7 consensus region.

RESULTS

Human papillomavirus DNA was detected in 51 (49.5%) breast carcinoma samples and 15 (15.8%) normal breast samples (p<0.0001). Human papillomavirus genotypes 6 and 11 were identified in 15.2% of all samples.

CONCLUSIONS

The high frequency of human papillomavirus infection in breast cancer samples indicates a potential role of this virus in breast carcinogenesis in the studied participants.

Evidence of No Association Between Human Papillomavirus and Breast Cancer

Background

Globally, breast cancer is the most frequent cancer among women. Studies reported an increased risk of breast cancer among women with prior cervical dysplasia. This study aimed to describe the prevalence of human papillomavirus (HPV) in breast cancer and explore if women with prior cervical neoplasia carry an increased risk of HPV-positive breast cancer compared to women without.

Methods

This case–control study identified 193 Danish women diagnosed with breast cancer (1998–2012) at Aarhus University Hospital or Copenhagen University Hospital Herlev. Cases were 93 women with cervical intraepithelial neoplasia grade 3 or worse (CIN3+) prior to breast cancer. Controls were 100 women without prior cervical dysplasia. HPV testing and genotyping were done using SPF₁₀ PCR-DEIA-LiPA₂₅ and an in-house semi-Q-PCR assay.

Results

Overall HPV prevalence in breast cancer for the assays was 1.55% (95% CI 0.32–4.48) and 0.52% (95% CI 0.01–2.85). There was no difference in HPV prevalence between cases and controls (2.15 vs. 1.00%, p = 0.61 and 1.08 vs. 0.00%, p = 0.48). HPV prevalence in CIN3+ was 94.62% (95% CI 0.88–0.98). Concordance between the assays was 98.60%.

Conclusion

HPV prevalence in breast cancer is very low suggesting no etiological correlation between HPV and breast cancer.

Prevalence of mucosal and cutaneous human papillomavirus in Moroccan breast cancer

BACKGROUND

Due to recent technical improvements and some encouraging new results, there has been a resurgence of interest in the possibility that a substantial proportion of breast cancers (BCs) may be caused by viral infections, including Human papillomavirus (HPV). The aim of this study was to determine the prevalence of mucosal and cutaneous HPV in tumours from Moroccan BC patients.

MATERIALS AND METHODS

Frozen tumours from 76 BC cases and 12 controls were evaluated for the presence of 62 HPV-types using highly sensitive assays that combine multiplex polymerase chain reaction and bead-based Luminex technology.

RESULTS

HPV DNA was found in 25.0% of BC tumours and only 8.3% of controls. Beta and gamma HPV types were found in 10.5% and 6.6% of BC tumours, respectively. High-risk mucosal types HPV16 and 18 were not detected in the subjects, but other probable/possible high-risk or high-risk -HPV types (HPV51, 52, 58, 59, and 66) were found in 5.3% of BC tumours. Statistical analysis showed no significant difference between, controls, BC cases and the inflammatory status (p > 0.05).

CONCLUSION

HPV DNA was found 3 times as frequently in the BC tumours as in the controls. However, this difference requires confirmation in a larger sample.

Is Human Papilloma Virus Associated with Breast Cancer? A Review of the Molecular Evidence

BACKGROUND

Although the association of human papillomavirus (HPV) with many cancers is well established, the involvement of HPV in breast cancer remains controversial. The purpose of this study is to perform a comprehensive review of the results and methods used to demonstrate that HPV markers are present in human breast cancer, and how well these studies fulfil the criteria for proving the viral etiology of a cancer.

STUDY DESIGN

We conducted a search for molecular studies published until November 2016 that relate human breast cancer to HPV.

RESULTS

Forty-three original molecular studies were found, some of which compared cases to nonneoplastic controls. Some investigations did not identify HPV in mammary tissue, but others identified it with different frequencies of positivity, varying between 1.2 and 86%. In most case-control studies (21/24 studies), positivity in cases was found to be higher than in controls, but odds ratios and confidence intervals were not reported.

CONCLUSION

The results are controversial. However, they arouse a great interest in the potential participation of HPV in breast carcinogenesis, but rather as an essential cause-effect participant, at least as a co-participant in some cases. The circumstance of HPV positivity in breast cancer can be criticized, but the elements that clearly demonstrate it in a number of cases are also relevant.

Detection of human papillomavirus DNA in tumors from Rwandese breast cancer patients

BACKGROUND

During the last decades, a great interest was given to viral etiology of breast cancer. Indeed, due to recent technical improvements and some encouraging new results, it has been a resurgence of interest in the possibility that a substantial proportion of human breast cancers may be caused by viral infections. High-risk genotypes of human papillomavirus (HPV) have been found in breast cancer cases. In the present study, we aimed to assess the presence of HPV DNA in breast cancer cases from Rwanda and to evaluate the association between HPV infection and clinico-pathological features.

METHODS

Therefore, a total of 47 archived formalin-fixed paraffin-embedded biopsies were collected and complete information was recorded. HPV detection and genotyping were done by PCR amplification and DNA sequencing.

RESULTS

Overall, HPV DNA was found in 46.81% of cases, HPV16 being the most prevalent subtype (77.27%) followed by HPV33 (13.64%) and HPV31 (9.09%). Comparison of HPV with clinico-pathological features showed no significant difference between HPV infection and breast localization, histological subtype, clinical stage, tumor grade, and intrinsic molecular subtypes.

CONCLUSIONS

These findings provide evidence of high prevalence of high-risk HPV in Rwandese patients with breast cancer and suggest that high-risk HPV infections could be a risk factor associated with human breast cancer development.

No detection of 'high-risk' human papillomaviruses in a group of Iranian women with breast cancer

The presence of viral DNA in breast cancer cells is controversial. However, some studies have revealed a possible role for the human papillomavirus in the pathogenesis of breast cancer. The aim of the present study was to investigate the presence of HPV-DNA in breast tissue in a group of Iranian women with and without breast cancer and identification of the detected HPV types. Paraffin-embedded specimens from 65 malignant breast cancer cases and 65 cases with benign breast lesions were investigated for presence of HPV-DNA by nested polymerase chain reaction. We found HPV-DNA in 22 (33.8%) of the breast cancer specimens. All non-cancerous specimens were negative. Low and high-risk HPV types, including HPV-6 (26.2%), HPV-16 (1.5%), HPV-35 (1.5%), HPV-52 (1.5%), and HPV-11 (1.5%) were detected in our study. HPV-6 was the most prevalent type in the breast cancer specimens. Although high-risk HPV types have been shown to have a major role in cervix cancer, there have been no data that support the same relevance for other types of malignancies. Furthermore, presence of low-risk HPV types in malignancies still is a matter of debate. The data presented in this study indicates a strong need for epidemiological studies correlating different HPV types in human breast cancer.

Molecular diagnosis and phylogenetic analysis of human papillomavirus type-16 from suspected patients in Pakistan

Background

Human Papillomavirus (HPV) is well known pathogen that can cause benign and malignant tumors in humans, yet there is very little information regarding HPV types prevalent in Pakistan.

Methods

A total of 92 cervical secretions were collected from suspected married female patients and used for DNA isolation using a novel isolation method. The samples were tested through Polymerase Chain Reaction (PCR) using already reported primers MY09/MY11, GP5/GP6, GP5+/GP6+, CP65/CP70, CP66/CP69 and SPF1/SPF2 and with those developed in this study including HRT1 and HRT2 primer sets for typing HPV types and HACTB primer set for human beta actin gene as internal positive control. Sequencing and phylogenetic analyses were performed for two isolates to determine circulating HPV types.

Results

PCR with HRT1 and HRT2 indicated 2 (2.17 %) patients were positive for HPV type- 16 while 1 (1.08 %) with HPV type 18. Sequencing and phylogenetic analysis of isolates confirmed HPV type-16 in genus alpha 9 which have 99 % homology with already reported HPV from Japan and Costa Rica.

Conclusion

This is the first report of HPV type-16 genus alpha 9 in Pakistan and the reported assay and sequence data will serve as valuable tools in further epidemiological studies for HPV surveillance to improve public health, especially of females in Pakistan.

Presence of human papillomavirus in breast cancer and its association with prognostic factors

Breast cancer accounts for 16% of all female cancers worldwide, and in Venezuela, it is the leading cause of death among women. Recently, the presence of high-risk genotypes of human papillomavirus (HPV) has been demonstrated in breast cancer and has been associated with histopathological features of the tumours. In Venezuela, there is no study which determines the association between the presence of HPV in breast cancer and the histopathological features. The aim of this investigation is to evaluate the presence of HPV in the different types of breast cancer, according to their molecular classification, based on the expression of ER, PR, HER2 and Ki67. With this purpose in mind, we assessed the presence of the HPV genome in 24 breast cancer samples diagnosed with infiltrating ductal carcinoma, ductal carcinoma in situ (DCIS) and lobular carcinoma, by the INNO-LIPA genotyping extra kit and the evaluation of the markers ER, PR, HER2, and Ki67 by immunohistochemistry. The viral genome was found in 41.67% of the total number of samples, 51 being the most frequent genotype with 30.77%, followed by types 18 and 33, with 23.08%, respectively. Most tumours were found in the group of luminal A, with a low range of Ki67 expression. The presence of HPV in breast tumours could affect their growth pattern and metastatic power.

Prevalence and correlation of human papilloma virus and its types with prognostic markers in patients with invasive ductal carcinoma of the breast in kuwait

OBJECTIVES

This study aimed to document the association of human papilloma virus (HPV) and its types in breast carcinoma tissues in Kuwaiti women, and correlate this with known prognostic markers.

METHODS

The clinicopathological data of archived tissue from 144 cases of invasive ductal breast carcinoma were studied (age, histological grade, size of tumour, lymph node metastases, oestrogen/progesterone receptors and human epidermal growth factor receptor 2 status). HPV frequency was documented using immunohistochemistry (IHC) and chromogenic in-situ hybridisation (CISH). HPV types were documented by CISH using HPV probes. CISH and IHC techniques were compared and HPV correlated with prognostic parameters.

RESULTS

The HPV prevalence as determined by CISH and IHC was 51 (35.4%) and 24 (16.7%) cases, respectively. The sensitivity of HPV by IHC was 37.3% and specificity was 94.6%. The sensitivity and specificity of HPV-CISH compared to HPVIHC was statistically significant (P <0.001). HPV-CISH was seen in 51 cases. A combination of HPV 6 and 11, and 16 and 18 was seen in 2 (3.9%) cases, and a combination of HPV 6, 11, 31 and 33 was seen in 7 (13.7%) cases. All three HPV probes: 6 and 11, 16 and 18, as well as 31 and 33 were present in 2 (3.9%) cases. The prevalence of HPVCISH in the Kuwaiti and non-Kuwaiti populations was 27 (52.9%) and 19 (37.2%), respectively. No correlation was observed with the prognostic parameters.

CONCLUSION

The frequency of HPV in breast carcinoma cases in Kuwait was 35.4% (CISH). Of those, 52.9% were Kuwaitis in whom both low- and high-risk HPV types were detected.

Carcinogenic viruses and solid cancers without sufficient evidence of causal association

Viral infections are important risk factors for tumor development in humans. Selected types of cancers, either lymphomas or carcinomas, for which there is sufficient evidence in humans of a causal association with specific viruses, have been identified. Experimental and clinical data on the possible association of other tumor types and carcinogenic viruses are presently controversial. In this article, we review the current evidence on the relationship between breast, colorectal and lung cancers and carcinogenic viruses. The majority of the publications reviewed do not provide definitive evidence that the viruses studied are associated with breast, colon and lung cancers. However, since this association may be clinically relevant for some tumor subtypes (i.e., lung cancer and papillomaviruses), there is an urgent need for further investigation on this topic. Using innovative laboratory techniques for viral detection on well-defined tumor types, National and International networks against cancer should encourage and organize concerted research programs on viruses and solid cancer association.

Prevalence of human papillomavirus in breast cancer: a systematic review

OBJECTIVE

We performed a systematic review and meta-analyses to estimate the prevalence of human papillomavirus (HPV) in breast carcinoma and to explore the reasons for the ongoing controversies about this issue.

MATERIALS AND METHODS

A comprehensive search of the Cochrane Library, MEDLINE, CANCERLIT, LILACS, and EMBASE databases was performed for papers published from January 1990 to January 2011. The medical subject heading terms were searched for the following: breast neoplasm, breast lesions, breast cancer, and HPV or human papillomavirus. Statistical analysis was performed using REVMAN 5.0.

RESULTS

Twenty-nine primary studies, including 2211 samples, were analyzed. Overall, HPV prevalence in patients with breast cancer was 23.0% (95% CI, 21.2%-24.8%). The prevalence of HPV ranged from 13.4% (95% CI, 10.2%-16%) in Europe to 42.9% (95% CI, 36.4%-49.4%) in North America and Australia. The prevalence of HPV in controls was 12.9%. Combinations of 9 case-control studies showed that breast cancer was associated with HPV (odds ratio, 5.9; 95% CI, 3.26-10.67).

CONCLUSION

We found a high prevalence of HPV DNA in breast cancer. There is strong evidence to suggest that HPV has an important role in the development of breast cancer.

Low prevalence of human papillomavirus (HPV) in Chinese patients with breast cancer

This retrospective study investigated the presence of human papillomavirus (HPV) in Chinese women with breast cancer, and the correlation between HPV infection and carcinogenesis. Tumour and non-cancerous breast tissue samples were obtained from 62 female patients with breast cancer; normal breast tissue samples were obtained from 46 women without breast cancer. HPV DNA was detected by nested polymerase chain reaction using consensus primers; HPV subtypes were determined by reverse dot blot and pyrosequencing analyses. HPV was found in tumour tissue samples from four of the 62 patients (6.5%), while no HPV DNA was detected in either the non-cancerous samples from patients with breast cancer or from the normal breast tissue controls. Of the four HPV-positive cases, three were HPV 16 positive (75%) and one was HPV 18 positive (25%). The low frequency of HPV detected in this study suggests that this infection is not a major risk factor in breast cancer development.

Are viruses associated with human breast cancer? Scrutinizing the molecular evidence

The three viruses most studied as possible causes of human breast cancer are mouse mammary tumor virus-like sequences (MMTV-LS), Epstein-Barr virus (EBV), and oncogenic (high risk) types of human papilloma virus (HPV). The first step in fulfilling traditional criteria for inferring that a cancer is caused by a virus is to demonstrate the virus in the affected tissue. Molecular techniques, compared to host antibody assessment and immunohistochemistry, are the most definitive in establishing viral presence. Results of 85 original molecular research investigations to detect one or more of the three viruses have been extremely divergent with no consensus reached. We evaluated the methodology of these studies for the following: type of molecular assay, DNA/RNA quality control, positive and negative assay controls, type of fixation, genome targets, methods for preventing and detecting molecular contamination, pathology of specimens processed, sample size, and proportion of specimens positive for the viral genome region targeted. Only seven of the studies convincingly demonstrated the presence of an oncogenic virus biomarker (EBV: 4/30 studies (13%); HPV 3/29 studies (10%), whereas 25 convincingly demonstrated absence of the virus studied (MMTV-LS: 4/25 (16%); EBV: 15/30 (50%); 6/29 (21%). The remainder of the studies suffered shortcomings, which, in our opinion, prevented a definitive conclusion. Only one of the studies compared frequency of the virus in breast tissue of breast cancer patients versus appropriate normal control subjects with no history of breast cancer. None of the studies were designed as epidemiologic studies to determine if the presence of the virus was significantly associated with breast cancer. Based on our evaluation, the data in the publications reviewed here remain preliminary, and do not justify a conclusion that MMTV-LS, HPV, or EBV are causally associated with breast cancer. However, they form a valuable basis for redirecting future studies.

Limited evidence of human papillomavirus in [corrected] breast tissue using molecular in situ methods

BACKGROUND

Human papillomavirus (HPV) has been proposed as an etiologic agent of breast cancer based on numerous reports of high-risk (oncogenic) HPV types in malignant breast tissues. However, most of those studies used standard and nested solution polymerase chain reaction (PCR) techniques, both of which are disadvantaged by vulnerability to laboratory contamination from positive control DNA and the inability to localize the signal to a specific cell type. To overcome these drawbacks, the authors of this report explored the use of in situ molecular methods of viral detection to reassess the frequency of HPV in malignant breast tissue.

METHODS

In situ hybridization (ISH) was used with probes that were specific for the capsid region of 12 oncogenic HPV types, and in situ PCR (IS-PCR) was used with primers that were specific for the capsid region of HPV-16, which is the most common oncogenic HPV type. These methods were resistant to molecular contamination and allowed identification of the positive cell type. The specimens examined were malignant tissues from patients with 70 breast cancer patients at The University of Texas M. D. Anderson Cancer Center in Houston, Texas.

RESULTS

HPV was observed in 4 of 70 specimens (5.7%) using ISH and in 2 of 70 specimens (2.9%) of specimens using IS-PCR. Concordance between the 2 methods was high for negative specimens; both methods yielded negative results in 66 of 70 specimens (94.3%). However, there was no concordance for the few positive specimens, probably because of differences in sensitivity and the targeted HPV types.

CONCLUSIONS

Oncogenic (high-risk) HPV types were present in malignant breast epithelium very infrequently and, thus, may be causative agents of only a relatively small proportion of all breast cancers.

Human papillomavirus infection and sporadic breast carcinoma risk: a meta-analysis

Despite an increase in the number of molecular epidemiological studies conducted in recent years to evaluate the association between HPV infection and risk of breast carcinoma, the studies remain inconclusive. Here, a meta-analysis was conducted to estimate the prevalence of HPV in breast carcinoma and test the association. Studies on HPV DNA detection in sporadic breast carcinoma in female using polymerase chain reaction were included. Information on overall and type-specific (HPV 6, 11, 16, 18, 31, 33, 35, 45 and 51) HPV prevalence were required, plus detailed descriptions of study populations, HPV DNA source, publication calendar period and PCR primers used for HPV DNA detection and typing. We revealed that 24.49% of the breast carcinoma cases were associated with HPV, 32.42% occurred in Asia and 12.91% in Europe. The four most commonly identified HPV types, in the order of decreased prevalence, were HPV33, 18, 16, and 35. The detection of HPV was mostly influenced by publication calendar period and PCR primers used. In addition, the analysis of ten case-control studies containing 447 breast carcinoma cases and 275 controls showed a significant increase in breast carcinoma risk with HPV positivity (OR = 3.63, 95% CI = 1.42-9.27). These results suggest that it's difficult to rule out the possibility of the association of HPV and breast carcinoma at present according to available publication proofs.

The role of human papillomavirus infection in breast cancer

Breast cancer is the leading female cancer and the third most common cause of cancer deaths worldwide. Many studies have suggested a possible link between breast cancer pathogenesis and viral infection, particularly mouse mammary tumour virus, simian virus 40, Epstein-Barr virus, and human papillomavirus (HPV). A significant number of recent studies have reported that approximately 29% of human breast cancer tissues were positive for high-risk HPV subtypes, especially HPV subtypes 16, 18, or 33. In contrast, several other investigations did not detect any HPV subtypes in either breast cancer tissue or normal breast tissue from patients diagnosed with breast cancer. Given these conflicting data and the established complexity of the association between HPV with other cancers, a definitive relationship between human breast cancer and HPV infection has not been determined. Recent advances in laboratory methodologies aim to overcome the inherent challenges in detecting HPV in breast cancer tissue. There is an urgent need to obtain additional evidence in order to assess the possibility of breast cancer prevention using HPV vaccines.

Breast cancer and human papillomavirus infection: no evidence of HPV etiology of breast cancer in Indian women

Background

Two clinically relevant high-risk HPV (HR-HPV) types 16 and 18 are etiologically associated with the development of cervical carcinoma and are also reported to be present in many other carcinomas in extra-genital organ sites. Presence of HPV has been reported in breast carcinoma which is the second most common cancer in India and is showing a fast rising trend in urban population. The two early genes E6 and E7 of HPV type 16 have been shown to immortalize breast epithelial cells in vitro, but the role of HPV infection in breast carcinogenesis is highly controversial. Present study has therefore been undertaken to analyze the prevalence of HPV infection in both breast cancer tissues and blood samples from a large number of Indian women with breast cancer from different geographic regions.

Methods

The presence of all mucosal HPVs and the most common high-risk HPV types 16 and 18 DNA was detected by two different PCR methods - (i) conventional PCR assays using consensus primers (MY09/11, or GP5+/GP6+) or HPV16 E6/E7 primers and (ii) highly sensitive Real-Time PCR. A total of 228 biopsies and corresponding 142 blood samples collected prospectively from 252 patients from four different regions of India with significant socio-cultural, ethnic and demographic variations were tested.

Results

All biopsies and blood samples of breast cancer patients tested by PCR methods did not show positivity for HPV DNA sequences in conventional PCRs either by MY09/11 or by GP5+/GP6+/HPV16 E6/E7 primers. Further testing of these samples by real time PCR also failed to detect HPV DNA sequences.

Conclusions

Lack of detection of HPV DNA either in the tumor or in the blood DNA of breast cancer patients by both conventional and real time PCR does not support a role of genital HPV in the pathogenesis of breast cancer in Indian women.

Vaccination against human papilloma virus (HPV): epidemiological evidence of HPV in non-genital cancers

Recently, the vaccine against human papillomavirus (HPV) was introduced in the national vaccination programmes of several countries worldwide. The established association between HPV and the progression of cervical neoplasia provides evidence of the expected protection of the vaccine against cervical cancer. During the last two decades several studies have also examined the possible involvement of HPV in non-genital cancers and have proposed the presence of HPV in oesophageal, laryngeal, oropharyngeal, lung, urothelial, breast and colon cancers. The possible involvement of HPV in these types of cancer would necessitate the introduction of the vaccine in both boys and girls. However, the role of HPV in the pathogenesis of these types of cancer has yet to be proven. Moreover, the controversial evidence of the possible impact of the vaccination against HPV in the prevention of non-genital cancers needs to be further evaluated. In this review, we present an overview of the existing epidemiological evidence regarding the detection of HPV in non-genital cancers.

No evidence of human papillomavirus DNA in breast carcinoma in Tunisian patients

The aim of this study was to evaluate the prevalence of broad range of anogenital HPVs in a series of 123 Tunisian breast carcinoma cases. PCR assays were performed to amplify regions within the L1, E1, E6 and E7 open reading frames of a broad range of anogenital HPVs and specific types HPV16, 18, 31 and 33. In addition, we performed an in situ hybridization analysis using HPV biotinylated DNA probes for the detection of broad spectrum of anogenital HPV types, high-risk HPV types (16 and 18), intermediate-risk HPV types (31 and 33) and low-risk HPV types (6 and 11). None of the 123 breast carcinoma samples showed PCR amplification of HPV DNA using the broad spectrum consensus primer-pairs E1-350L/E1-547R and GP5+/GP6+ primers. Furthermore, neither high risk nor low-risk HPV types were detected in any of these cases. Moreover, using in situ hybridization for the detection of HPVs, we failed to detect a positive signal in neoplastic cells in any case. Our results suggest that anogenital papillomaviruses are unlikely to play a role in the development of breast carcinomas in Tunisian patients.

Detection of cutaneous HPV types 4 and 24 DNA sequences in breast carcinoma in Singaporean women of Asian ancestry

AIM

To date, there have been conflicting data on the prevalence of HPV in primary breast carcinoma, with a median prevalence of 35%. We believe that the low prevalence reported could be due to use of inappropriate amplification primers and methods of detection. We designed a study to detect and reflect more accurately the incidence of both mucosal and cutaneous HPV types in breast carcinoma among Singaporean women.

METHODS

In our study, we used two different molecular techniques, both of which involved a polymerase chain reaction (PCR) amplification step for any HPV DNA found in the breast cancer tissues. The first method targeted primarily the mucosal HPV types, and the second, primarily the cutaneous HPV types. Formalin-fixed, paraffin-embedded breast cancers were used for the studies. The first method involved the GP5+/GP6+ primers for PCR amplification and a commercially available HPV DNA genotyping chip for detection. The subsequent studies involved the use of the FAB 59/64 primers for amplification, followed by DNA sequencing and comparison to the NCBI GenBank database for the detection of all possible HPV types.

RESULTS

With the first technique, all 92 breast cancers tested gave negative results for HPV DNA, suggesting the absence of HPV types in breast cancers. Using the second method, we detected HPV sequences in 32/92 (35%) samples, of which 28 were shown to be HPV-4, one was HPV-24, two had mixed HPV types and one had an indeterminate HPV sequence that did not match any of the HPV sequences deposited in the GenBank database.

CONCLUSIONS

These results were consistent with our hypothesis that the true incidence of HPV in breast carcinoma is much higher than those reported to date, and that this is probably due to the limited sensitivity of the molecular techniques used in earlier studies.

Human papillomavirus (HPV) in breast tumors: prevalence in a group of Mexican patients

Background

Breast cancer is one of the main health problems in developed countries, occupying first place in mortality in women. It is well-known that there are risk factors associated with breast cancer development. Nonetheless, in 50–80% of cases known risk factors have not been identified, this has generated the attempt to identify new factors related with this neoplasia as viral infections. The aim of this work is investigate the prevalence of HPV DNA in patients with breast lesions at the Instituto Nacional de Cancerologia de Mexico.

Methods

Fifty-one cases of breast cancer were selected from the files of the institute and compared by age and tumor size with 43 cases of non malignant breast lesions (fibroadenoma, fibrocystic disease and phyllodes tumor). Paraffin embedded specimens were selected, HPV DNA was analyzed by polymerase chain reaction (PCR) and sequenced for different types of HPV in case of positivity for HPV-DNA. Descriptive analysis of clinical and pathological variables was performed and comparisons between positive and negative cases was done.

Results

All patients were mexican, mean age was 53.3, median age of menarche was 13 and median tumor size 9 cms. Cervicovaginal cytology was performed to all patients, 1 patient (1.9%) of cancer group had HPV and none in the other group, no cases were diagnosed with cervical dysplasia. In the group of carcinomas 36 (70.5%) were negative and 15 (29.4%) were positive to HPV-DNA, 10(66.6%) were positive for HPV 16, 3(20%) for HPV 18, two cases (13.4%) were positive for both. In the group of benign conditions all were negative to HPV-DNA.

Conclusion

Presence of HPV in breast cancer in our group of cases is high in comparison to other authors; larger numbers of cases need to be analyzed in order to establish the exact role of this virus in the pathogenesis of breast cancer.

High-risk human papillomavirus infections in breast cancer in Syrian women and their association with Id-1 expression: a tissue microarray study

High-risk human papillomaviruses (HPVs) could be important risk factors for breast carcinogenesis and metastasis. Based on this hypothesis, we recently studied the effect of E6/E7 onco-proteins of high-risk HPV type 16 in two non-invasive human breast cancer cell lines, BT20 and MCF7; we reported that E6/E7 converts these cell lines to invasive cells. This is accompanied by an overexpression of Id-1, which is an important regulator of breast metastasis. In this investigation, we examined the presence of high-risk HPVs (16, 18, 31, 33 and 35) and the expression of their E6 onco-protein as well as their correlation with Id-1 gene expression, using polymerase chain reaction (PCR) and tissue microarray (TMA) analysis, respectively, in a cohort of 113 Syrian breast cancer patients. We found that high-risk HPV types 16, 18, 31, 33 and 35 are present in 8.84, 9.73, 7.07, 55.75 and 37.16% of our samples, respectively, which represent invasive breast cancers. Overall, 69 (61.06%) of the 113 samples are HPV positive; among these specimens 24 tissues (34.78%) are coinfected with more than one HPV type. Furthermore, we report that the expression of the E6 onco-protein of these high-risk HPVs is correlated with Id-1 overexpression in the majority of invasive breast cancer tissue samples. Our data suggest that high-risk HPV infections are associated with human breast cancer progression in Syrian women.

Detection of human papillomavirus DNA by DNA chip in breast carcinomas of Korean women

It remains unclear whether there is an association between human papillomavirus (HPV) infection and human breast cancer. The aim of this study was to investigate the presence of HPV DNA in breast carcinomas of Korean women and to examine the possible association between HPV and breast cancer development. For this purpose, HPV DNAs from 154 patients, including 123 patients with breast carcinoma and 31 with intraductal papilloma, and nipple tissue from 27 cancer patients were examined using the DNA chip method. HPV DNA was detected in 8 breast carcinomas (6.5%) but in no intraductal papilloma. All detected HPV genotypes were of high-risk groups. There was a slightly increased incidence in papillary carcinomas (11.5%) and invasive ductal carcinomas with adjacent intraductal papillomas (11.8%) compared to the other histological subtypes (3.2-4.3%), although the difference was not statistically significant (p = 0.126). The presence of HPV DNA was not correlated with specific prognostic predictors of disease. High-risk HPV DNA sequences were present in 6.5% of Korean patients with breast tumors. However, this study could not demonstrate whether or not such HPVs directly contribute to the development of breast cancer.

Lymphoepithelioma-like carcinoma of the breast: not Epstein-Barr virus-, but human papilloma virus-positive

Lymphoepithelioma-like carcinoma of the breast is a rare tumor, with fewer than 20 cases documented in the literature. None of the published cases was Epstein-Barr virus positive, and our case was also Epstein-Barr virus negative. However, in our case, human papilloma virus (HPV) types 18 and 33 DNA could be demonstrated within the tumor tissue. Many years previously, the patient underwent hysterectomy for cervical carcinoma in situ which showed the presence of HPV-33. To the best of our knowledge, this is the first report on lymphoepithelioma-like carcinoma of the breast where high-risk HPV infection may be suggested as an etiological factor in a patient with a previous history of cervical carcinoma in situ.

No evidence of human papillomavirus DNA sequences in invasive breast carcinoma

Breast cancer is one of the most frequently diagnosed cancers in women in France, but its aetiology remains unknown. Viruses including Epstein-Barr virus (EBV), a human equivalent of murine mammary tumour virus (MMTV) and human papillomavirus (HPV) have been detected in benign breast tissues and breast tumours and are considered to be involved in the aetiology of breast cancer. The aim of this study was to determine the prevalence of high-risk oncogenic HPVs in breast carcinoma from French patients. Fifty unselected DNA samples extracted from invasive breast carcinoma tissues were analysed. Polymerase chain reaction (PCR) was performed to amplify both consensus GP5+/GP6+HPV sequences and specific sequences for HPV types 16, 18, 33, 45 and 6-11. No HPV-DNA sequences were detected in our series of 50 samples. These data argue against the role of oncogenic HPV in the pathogenesis of breast cancer.

Breast cancer and human papillomavirus (HPV) infection: no evidence of a viral etiology in a group of Swiss women

There are controversial data on the meaning of viral induction of breast cancer. The aim of this study was to investigate the presence of human papillomavirus (HPV) DNA in patients with breast carcinoma and the correlation of viral infection with disease outcome. Paraffin-embedded sections from 81 patients with breast cancer were analyzed for HPV DNA by polymerase chain reaction (PCR) using the SPF1/2 primers covering about 40 different low-, intermediate- and high-risk types. We found all samples were negative for HPV DNA. Our analysis could not support a role of HPV in breast carcinoma. Controversial published data indicate a need for further, larger epidemiologic studies.

Could human papillomaviruses be spread through blood?

The human papillomaviruses (HPVs) are epitheliotropic viruses that require the environment of a differentiating squamous epithelium for their life cycle. HPV infection through abrasion of the skin or sexual intercourse causes benign warts and sometimes cancer. HPV DNA detected in the blood has been interpreted as having originated from metastasized cancer cells. The present study examined HPV DNA in banked, frozen peripheral blood mononuclear cells (PBMCs) from 57 U.S. human immunodeficiency virus (HIV)-infected pediatric patients collected between 1987 and 1996 and in fresh PBMCs from 19 healthy blood donors collected in 2002 to 2003. Eight patients and three blood donors were positive mostly for two subgroups of the HPV type 16 genome. The HPV genome detected in all 11 PBMC samples existed as an episomal form, albeit at a low DNA copy number. Among the eight patients, seven acquired HIV from transfusion (three associated with hemophilia) and one acquired HIV through vertical transmission; this patient also had received a transfusion before sampling. Our data suggest that PBMCs may be HPV carriers and might spread the virus through blood.

Touchdown General Primer (GP5+/GP6+) PCR and optimized sample DNA concentration support the sensitive detection of human papillomavirus

Background

The GP5+/GP6+ PCR assay is a well-established HPV detection technique. This study has examined the effects of incorporating 'hot start' and 'touchdown' steps into the protocol. In addition, dTTP was substituted with dUTP to permit contamination control measures against carry-over PCR product.

Methods

Firstly, HPV-16 was amplified from SiHa cell DNA (0.1 ng–100 ng) diluted in a background of C-33A DNA (100 ng-2 μg). Secondly, the detection of small quantities (15ag-1.5pg) of HPV recombinant plasmids (types 16, 31, 33, 45, 51, 52, and 56) diluted in C-33A DNA was investigated. Thirdly, clinical sample DNA extracts (cervical smears, formalin-fixed vaginal lesions and breast tumors) were tested for HPV. Six different PCR protocols were assessed. HPV was detected by gel electrophoresis, and by Southern and dot blot hybridization.

Results

HPV detection sensitivity was dependent on the total amount of DNA in a PCR. Touchdown protocols supported HPV-16 detection from 1 ng or 0.5 ng SiHa cell DNA in a background of 2 μg or 1 μg C-33A DNA respectively, and from 0.1 ng of SiHa cell DNA (~28 copies HPV-16) in 500 ng or 100 ng background DNA. Under standard GP5+/GP6+ annealing conditions, HPV-16 went undetected when the DNA content of a PCR was 2 μg or 1 μg, and with 500 ng C-33A DNA the sensitivity limit was 1 ng SiHa cell DNA. HPV recombinant plasmids were each detected with high (albeit varying) sensitivity by a touchdown protocol. HPV-31 was better amplified under standard annealing conditions (1.5fg in 100 ng background DNA) than by a touchdown approach (15fg detection limit). HPV-52 was not amplified by the standard protocol at the dilutions tested. Seventeen different HPV types were demonstrated in 47/65 (72%) abnormal cytology samples recorded as HPV negative by standard GP5+/GP6+ conditions. Twenty-one different HPV types were recorded in 111/114 (97%) vaginal lesions. Multiple infections were also detectable using a touchdown approach. Of 26 breast tumors, 5 (19%) tested HPV positive by the standard assay and 15/26 (58%) using a touchdown protocol.

Conclusion

Touchdown modification of the GP5+/GP6+ PCR assay enables the detection of HPV undetected under regular assay conditions. The use of standardized DNA quantities in a PCR rather than standard sample volumes containing arbitrary amounts of DNA is supported. A touchdown approach may be beneficial as an analytical test for the re-evaluation of (apparently) HPV negative abnormal cervical cytological or histological samples, and for investigating the association of HPV with disease conditions at diverse organ sites. The clinical utility of a touchdown approach for HPV detection requires further investigation as increased assay analytical sensitivity may not necessarily equate with improved clinical sensitivity or specificity.

Detection of human papillomavirus DNA in breast cancer of patients with cervical cancer history

BACKGROUND

Recent studies have revealed a possible role for the human papillomavirus (HPV) in the pathogenesis of breast cancer. In this study, patients having both a history of invasive cervical cancer and breast cancer as second primary cancer were selected for enrolment in a study of breast carcinomas for the presence of HPV.

METHODS

Paraffin-embedded tissue from cervical cancer, pelvic lymph nodes, breast cancer and axillary lymph nodes of eleven patients were examined for the presence of HPV DNA using a polymerase chain reaction - enzyme immuno assay. DNA extraction was performed with the "QIAamp Tissue Kit" according to the manufacturer's instructions. Additionally, serum samples taken between diagnosis of cervical and breast cancer, were analyzed for the presence of HPV DNA to examine a possible haematogenous spread of oncogenic HPV DNA.

RESULTS

All cervical carcinomas were HPV-positive. HPV DNA was detected in seven out of eleven cases in breast cancer and/or axillary lymph node tissue. Six patients had the same HPV type (HPV-16) in cervical cancer and in the corresponding breast cancer/lymph node tissue. In one case, the same HPV DNA type (HPV 16) was detected in cervical cancer, breast cancer and serum sample.

CONCLUSION

These results suggest that HPV DNA might be transported from the original site of infection to the breast tissue by the bloodstream, and that it is possibly involved in the carcinogenesis of breast neoplasia in some patients.

Presence of papillomavirus sequences in condylomatous lesions of the mamillae and in invasive carcinoma of the breast

BACKGROUND

Viruses including Epstein-Barr virus (EBV), a human equivalent of murine mammary tumour virus (MMTV) and human papillomavirus (HPV) have been implicated in the aetiology of human breast cancer. We report the presence of HPV DNA sequences in areolar tissue and tumour tissue samples from female patients with breast carcinoma. The presence of virus in the areolar-nipple complex suggests to us a potential pathogenic mechanism.

METHODS

Polymerase chain reaction (PCR) was undertaken to amplify HPV types in areolar and tumour tissue from breast cancer cases. In situ hybridisation supported the PCR findings and localised the virus in nipple, areolar and tumour tissue.

RESULTS

Papillomavirus DNA was present in 25 of 29 samples of breast carcinoma and in 20 of 29 samples from the corresponding mamilla. The most prevalent type in both carcinomas and nipples was HPV 11, followed by HPV 6. Other types detected were HPV 16, 23, 27 and 57 (nipples and carcinomas), HPV 20, 21, 32, 37, 38, 66 and GA3-1 (nipples only) and HPV 3, 15, 24, 87 and DL473 (carcinomas only). Multiple types were demonstrated in seven carcinomas and ten nipple samples.

CONCLUSIONS

The data demonstrate the occurrence of HPV in nipple and areolar tissues in patients with breast carcinoma. The authors postulate a retrograde ductular pattern of viral spread that may have pathogenic significance.

Evidence for an association of human papillomavirus and breast carcinomas

Human papillomavirus (HPV) DNA has been detected in breast carcinoma by different laboratorial techniques, suggesting the virus could play a role in the pathogenesis of this tumor. The aim of the present study is to investigate the presence of HPV in patients with breast carcinoma and the correlation of the viral infection with prognostic factors for the disease outcome. Between June 2001 and July 2002, 101 paraffin embedded breast carcinoma specimens were analyzed through polymerase chain reaction (PCR) and sequencing of HPV-E6 gene. Twenty specimens of reduction mammoplasty and 21 specimens of fibroadenomas were also studied as a non-malignant control group. Two different specific primer sets targeting E6 region of the HPVs 16 and 18 were used for the analysis. The HPV DNA was detected in 25 breast carcinomas (24.75%), but in none of the benign breast specimens ( p < 0.001). Out of the 25 positive cases, 14 were HPV-16 positive (56%) and 10 were HPV-18 positive (40%). An original finding was the detection of both HPV-16 and -18 in a single tumor (4%). The amplified viral sequences confirmed the presence of HPV-16 and -18. No correlation between the presence of HPV DNA and specific prognostic predictors for the disease outcome was observed. Our results suggest that the presence in the breast of either HPV-16 or -18 might be related to development of the malignant phenotype. Further studies are warranted.