HPV Status and Its Correlation with BCL2, p21, p53, Rb, and Survivin Expression in Breast Cancer in a Chinese Population. Biomed Res Int. 2017;2017:6315392. [PMID: 29423411 PMCID: PMC5750508 DOI: 10.1155/2017/6315392]

The Role of Oncogenic Viruses in the Pathogenesis of Sporadic Breast Cancer: A Comprehensive Review of the Current Literature

Breast cancer is the most common malignancy in the female sex; although recent therapies have significantly changed the natural history of this cancer, it remains a significant challenge. In the past decade, evidence has been put forward that some oncogenic viruses may play a role in the development of sporadic breast cancer; however, data are scattered and mostly reported as sparse case series or small case-control studies. In this review, we organize and report current evidence regarding the role of high-risk human papillomavirus, mouse mammary tumor virus, Epstein-Barr virus, cytomegalovirus, bovine leukemia virus, human polyomavirus 2, and Merkel cell polyomavirus in the pathogenesis of breast cancer.

Human papillomaviruses and breast cancer: A systematic review and meta‑analysis

Breast cancer (BC) is the leading malignancy worldwide. The association between human papillomavirus (HPV) and BC is debatable. The present systematic review and meta-analysis aimed to assess the prevalence of HPV DNA in malignant breast tumors. An extensive search of the PubMed and SCOPUS databases was carried out for case-control studies published between January 1, 2003 and January 7, 2023, which compared HPV DNA detection in breast tissue specimens of female patients with BC and women with absent or benign breast disorders. Once the initial title/abstract screening was completed by two independent investigators, the full texts of the included studies from that stage were reviewed by the aforementioned investigators to determine if they should be included in the present study. Data extraction was independently conducted by two investigators. A third investigator was consulted to resolve disagreements through free discussion. MedCalc was used for quantitative synthesis. The significance of association was estimated by pooled odds ratios (ORs) with 95% confidence intervals (CIs) calculated using the random-effects model. A total of 23 primary studies, including 3,243 subjects (2,027 patients and 1,216 controls), were eligible for quantitative analysis. HPV prevalence in patients with BC and controls was 21.95 and 8.96%, respectively. The prevalence of HPV differed significantly between the two groups (OR 3.83; 95% CI 2.03-7.25; P<0.01). Heterogeneity among studies was quantified using the I2 index which was 69.57% (95% CI 51.89-80.75). The risk of bias was assessed using an appropriate tool contributed by the CLARITY Group at McMaster University. Seven studies had a low risk of bias, 15 studies had a moderate risk of bias and only one study had a serious risk of bias. These results reinforce the hypothesis that HPV is involved in BC development and progression, indicating a possible role of HPV vaccination in BC prevention.

Emerging evidence on the role of breast microbiota on the development of breast cancer in high-risk patients

Cancer is a multi-factorial disease, and the etiology of breast cancer (BC) is due to a combination of both genetic and environmental factors. Breast tissue shows a unique microbiota, Proteobacteria and Firmicutes are the most abundant bacteria in breast tissue, and several studies have shown that the microbiota of healthy breast differs from that of BC. Breast microbiota appears to be correlated with different characteristics of the tumor, and prognostic clinicopathologic features. It also appears that there are subtle differences between the microbial profiles of the healthy control and high-risk patients. Genetic predisposition is an extremely important risk factor for BC. BRCA1/2 germline mutations and Li-Fraumeni syndrome are DNA repair deficiency syndromes inherited as autosomal dominant characters that substantially increase the risk of BC. These syndromes exhibit incomplete penetrance of BC expression in carrier subjects. The action of breast microbiota on carcinogenesis might explain why women with a mutation develop cancer and others do not. Among the potential biological pathways through which the breast microbiota may affect tumorigenesis, the most relevant appear to be DNA damage caused by colibactin and other bacterial-derived genotoxins, β-glucuronidase-mediated estrogen deconjugation and reactivation, and HPV-mediated cancer susceptibility. In conclusion, in patients with a genetic predisposition, an unfavorable breast microbiota may be co-responsible for the onset of BC. Prospectively, the ability to modulate the microbiota may have an impact on disease onset and progression in patients at high risk for BC.

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.

Human papillomavirus maybe is a critical player in the regulation of chemoresistance related factors (P53, Rb, TWIST, Bcl-2, Bcl-XL, c-IAP2, cytochrome C, and caspase 3) in breast cancer

As one of the frequent malignancies, breast cancer (BCa) is the foremost reason for cancer-related deaths among women. The role of Human papillomavirus (HPV) in chemoresistance has rarely been investigated in previous studies. The current study sets out to the possible role of HPV in BCa chemoresistance. In this research, 90 BCa tissue and 33 normal breast tissue were collected. We evaluated the presence of the HPV genome along with the viral (E2, E6, E7) and cellular gene expression associated with cell resistance to death. Statically significant differences in the prevalence of HPV between the BCa group (25.2% or 23/90) and the control group (21.8% or 7/32) were not found. HPV-16 and HPV-18 genotypes were the abundant HPV genotypes. Resistance to the Adriamycin-Cyclophosphamide (AC), paclitaxel regimen was elevated in the HPV- group (56/70) in comparison to the HPV+ group (14/70). Nevertheless, there was no significant difference in the prevalence of resistance to AC + paclitaxel + triple-negative breast cancer combination therapy between the HPV+ group (9/20) and in the HPV- group (11/20). In the BCa group in contrast to the control group, the expression level of Bcl-2, BCL-XL, and c-IAP2 demonstrated a significant decrease, while, the expression level of cytochrome C and caspase 3 was significantly increased. This study suggests that HPV infection might contribute to BCa chemoresistance through disrupt cellular genes involved in cell death.

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.

Correlation between HPV PCNA, p16, and p21 Expression in Lung Cancer Patients

Purpose. Evaluate if human papillomavirus (HPV) infection in lung cancer patients might be helping cancer development by altering p16, p21, and PCNA, key human genes involved in cell proliferation and tumor development. Methods. 63 fresh-frozen (FF) and formalin-fixed paraffin-embedded (FFPE) samples from lung tumor patients were used to detect HPV by PCR, followed by genotype through sequencing. The host gene expressions of p21, p16, and PCNA were quantified by qPCR in both FF and FFPE samples, and the expression of viral oncogenes E5, E6, and E7 was also measured by qPCR in 19 FF samples. Results. 74.6% of samples were positive for HPV, 33/44 FFPE samples and 14/19 FF samples. HPV-16 and HPV-18 were detected in 31/33 and 7/33 FFPE, respectively, and HPV-16 was the only type in FF samples. E5, E6, and E7 were expressed in 10/19, 2/19, and 4/19 FF samples, respectively. The p16 RNAm expression was higher in FF HPV+ samples and FFPE+FF HPV+ samples, while p21 showed higher expression in all HPV- samples. In turn, the PCNA expression was higher in HPV+ FF samples; however, in FFPE and FFPE+FF samples, PCNA was higher in HPV- samples. In FF samples, PCNA, p16, and p21 showed a significant positive correlation as well as E5 and E7, and E5 was inversely correlated to p21. In FFPE, also, a positive correlation was observed between PCNA HPV+ and p21 HPV+ and PCNA HPV+ and p16 HPV. In FF+FFPE analysis, a direct correlation was found between PCNA HPV+ and p21 HPV+, p21 HPV+ and p16 HPV+, and PCNA HPV- and p16 HPV-, and an inverse correlation between PCNA HPV+ and p16 HPV+. Also, the p16 protein was positive in 10 HPV+ samples and 1 HPV-. Conclusions. Our data show that lung cancer patients from Northeast Brazil have a high prevalence of HPV, and the virus also expresses its oncogenes and correlates with key human genes involved in tumor development. This data could instigate the development of studies focused on preventive strategies, such as vaccination, used as a prognostic indicator and/or individualized therapy.

Presence of Human Papillomavirus DNA in Malignant Neoplasia and Non-Malignant Breast Disease

Breast cancer is the leading cause of cancer death among women worldwide. Multiple extrinsic and intrinsic factors are associated with this disease’s development. Various research groups worldwide have reported the presence of human papillomavirus (HPV) DNA in samples of malignant breast tumors. Although its role in mammary carcinogenesis is not fully understood, it is known that the HPV genome, once inserted into host cells, has oncogenic capabilities. The present study aimed to detect the presence of HPV DNA in 116 breast tissue biopsies and classify them according to their histology. It was found that 50.9% of the breast biopsies analyzed were malignant neoplasms, of which 74.6% were histologically classified as infiltrating ductal carcinoma. In biopsies with non-malignant breast disease, fibroadenoma was the most common benign neoplasm (39.1%). Detection of HPV DNA was performed through nested PCR using the external primer MY09/11 and the internal primer GP5+/6+. A hybridization assay genotyped HPV. HPV DNA was identified in 20.3% (12/59) of malignant neoplasms and 35% non-malignant breast disease (16/46). It was also detected in 27.3% (3/11) of breast tissue biopsies without alteration. However, there are no statistically significant differences between these groups and the existence of HPV DNA (p = 0.2521). Its presence was more frequent in non-malignant alterations than in malignant neoplasias. The most frequent genotypes in the HPV-positive samples were low-risk (LR) HPV-42 followed by high-risk (HR) HPV-31.

Association of human papillomavirus with breast cancer: a new perspective on an old debate

Breast cancer is a common cancer in the female population. Despite remarkable progress in the treatment of this cancer, its exact etiology is still unknown. Since the first evidence of an association between breast cancer and human papillomavirus (HPV) was provided in 1992, numerous studies have explored this subject but have reached contradictory results. In this review, the authors examine the existing evidence and hypotheses regarding the pathways whereby HPV infection can reach breast cells and the mediators linking HPV oncoproteins to breast cancer pathogenesis. Furthermore, the authors discuss contradictory findings regarding the association of HPV with breast cancer. Showing the link between HPV infection and increased genomic instability, reduced apoptosis, immune system dysfunction and progression of metastasis, the reviewed findings highlight the importance of active presence or history of HPV infection as a prognostic factor for breast tumor development.

Molecular Mechanisms of HIV Protease Inhibitors Against HPV-Associated Cervical Cancer: Restoration of TP53 Tumour Suppressor Activities

Cervical cancer is a Human Papilloma virus-related disease, which is on the rise in a number of countries, globally. Two essential oncogenes, E6 and E7, drive cell transformation and cancer development. These two oncoproteins target two of the most important tumour suppressors, p53 and pRB, for degradation through the ubiquitin ligase pathway, thus, blocking apoptosis activation and deregulation of cell cycle. This pathway can be exploited for anticancer therapeutic interventions, and Human Immunodeficiency Virus Protease Inhibitors (HIV-PIs) have attracted a lot of attention for this anticancer drug development. HIV-PIs have proven effective in treating HPV-positive cervical cancers and shown to restore impaired or deregulated p53 in HPV-associated cervical cancers by inhibiting the 26S proteasome. This review will evaluate the role players, such as HPV oncoproteins involved cervical cancer development and how they are targeted in HIV protease inhibitors-induced p53 restoration in cervical cancer. This review also covers the therapeutic potential of HIV protease inhibitors and molecular mechanisms behind the HIV protease inhibitors-induced p53-dependent anticancer activities against cervical cancer.

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.

Low frequency of HPV positivity in breast tumors among patients from south-central Poland

Background

Some studies suggest that Human Papilloma Virus (HPV) infection is important factor in carcinogenesis of breast tumors. This study’ objective was to analyze HPV prevalence in breast cancers of patients from south-central Poland.

Materials and methods

The study was performed based on archival paraffin embebbed and formalin fixed blocks in the group of 383 patients with breast cancer. HPV prevalence and its genotype were assessed, respectively by: nested PCR (with two groups of primers: PGMY09/PGMY11 and GP5+/GP6+), quantitative PCR (qPCR). Tumors were classified as HPV positive in case of at least one positive result in nested PCR and positive results in genotyping procedure. For all HPV positive tissues P16 immunostaining was applied in order to confirm active viral infection.

Results

In the group of 383 breast cancers, HPV positivity was found in 17 samples (4.4%) in nested PCR. All these samples were subjected to HPV genotyping. This analysis revealed presence of HPV type 16 into two tumors (0.5%). In these two cancers, P16 overexpression was reported.

Conclusion

In breast tumors of patients from south-central Poland in Poland, HPV positivity is demonstrated in very low percentage of cases.

Human Papillomavirus in Breast Carcinogenesis: A Passenger, a Cofactor, or a Causal Agent?

Simple Summary

Breast cancer (BC) is the most frequent tumor in women worldwide. A minority of BC patients have a family history of the disease, suggesting the importance of environmental and lifestyle factors. Human papillomavirus (HPV) infection has been detected in a subset of tumors, suggesting a potential role in BC. In this review, we summarized relevant information in respect to this topic and we propose a model of HPV-mediated breast carcinogenesis. Evidence suggests that breast tissue is accessible to HPV, which may be a causal agent of BC in a subset of cases.

Abstract

Breast cancer (BC) is the most commonly diagnosed malignancy in women worldwide as well as the leading cause of cancer-related death in this gender. Studies have identified that human papillomavirus (HPV) is a potential risk factor for BC development. While vaccines that protect against oncogenic HPVs infection have been commercially available, global disparities persist due to their high cost. Interestingly, numerous authors have detected an increased high risk (HR)-HPV infection in BC specimens when compared with non-tumor tissues. Therefore, it was suggested that HR-HPV infection could play a role in breast carcinogenesis in a subset of cases. Additional epidemiological and experimental evidence is still needed regarding the role of HR-HPV infection in the development and progression of BC.

Human papillomavirus and prostate cancer: The role of viral expressed proteins in the inhibition of anoikis and induction of metastasis

BACKGROUND

The aim of this study is to address the role of HPV in prostate cancer (PCa) development through the inducement of resistance to anoikis.

METHODS

In this case-control study, prostate tissues and blood samples were collected from 116 individuals, including 72 cases with PCa and 44 non-malignant prostate tissue samples as a control group. The expression level of HPV genes (E2, E6, and E7) and cellular genes including anti-apoptotic mediators (Bcl-2 and survivin), tumor suppressor proteins (Rb and p53), and some mediators involved in anoikis resistance and invasiveness (E-cadherin, N-cadherin, Twist, PTPN13 and SLUG) were evaluated.

RESULTS

HPV genome was identified in 36.1% cases and 15.9% control samples, additionally there was found to be a statistic significant association between the presence of HPV and PCa (OR = 1.64, 95% C.I = 0.8-1.8, P-value = 0.023). HPV genotype 16 and 18 were the most prevalent genotype in both in the PCa group and the control group. The expression level of the tumor suppressor proteins (Rb and p53) and anti-apoptotic mediators (Bcl-2 and Survivin) were significantly decreased and increased, respectively, in the HPV-positive specimens compared to the HPV-negative specimens. Furthermore, the mean expression level of N-cadherin, SLUG, and TWIST in the HPV-positive specimens was higher than HPV-negative specimens while the mean expression level of PTPN-13 and E-cadherin genes in the HPV-positive specimens was lower than HPV-negative specimens.

CONCLUSION

Our study suggests that HPV infection may be involved in the development of PCa metastases by modulating anoikis resistance related genes.

Human papillomavirus, gene mutation and estrogen and progesterone receptors in breast cancer: a cross-sectional study

Introduction

recent studies show a good relationship between breast cancer (BC) and human papillomaviruses (HPV) wich is responsible for about 18% of BC cases. This study aimed to assess the relationship between different genotypes of HPV and the expression of P53 and retinoblastoma (RB) genes and estrogen and progesterone receptors in BC among Sudanese women.

Methods

one hundred and fifty tissue blocks were obtained from females diagnosed with BC. Positive samples were used to determine genotypes with an applied biosystem (ABI 3730XL) genetic analyzer for sequencing and immunohistochemistry.

Results

13/150 samples showed HPV DNA. High-risk HPV-16 was detected in 5 cases, high-risk-HPV-58 was found in four cases, and HPV-18 was detected in three cases. Low-risk-HPV-11 was detected in a single invasive lobular carcinoma (ILC) case. P53 and RB gene mutations were detected in 35 and 30 BC cases, respectively. P53 gene mutation was frequently identified in grade (III) BC while RB gene mutation was positive in grade (II). Grade (II) BC had a higher incidence of HPV-16 and 58. On the other hand, HPV-18 had a higher incidence in grade (III). Estrogen and progesterone receptors were expressed in 94 and 79 HPV cases among the study group, respectively.

Conclusion

this study elucidates the associations between HPV genotypes and BC. A statistically significant association was observed among p53 and RB gene mutations and different BC histological types. On the other hand, there was a statistically insignificant association between HPV genotyping and different BC gradings, BC histological types, P53 and RB genes mutations, and estrogen and progesterone receptor expression. Also, there was a statistically insignificant association among estrogen and progesterone receptors expression and BC grading. RB gene mutation was significantly associated with different BC grades. On the other hand, there was a statistically insignificant association between progesterone receptor expression and BC.

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 assessment of a possible link between HPV-mediated inflammation, apoptosis, and angiogenesis in Prostate cancer

BACKGROUND

The aim of this study was to determine the presence of HPV in patients with Prostate cancer (PCa) and its possible association with cancer progression.

METHODS

In this case-control study, fresh prostate tissues and blood samples were collected from 90 individuals, including 58 cases samples with PCa and 32 non-malignant prostate tissue samples as a control group. The expression level of viral genes (E2, E6, and E7) and cellular factors including tumor suppressor proteins (Rb and p53), anti-apoptotic mediators (Bcl-2 and survivin), and some mediators involved in inflammation and angiogenesis was evaluated.

RESULTS

The presence of the HPV genome was identified in 19 out of the 58 cases (32.7%) and five out of the 32 controls (15.6%). However, there was not any statistically significant relationship between the presence of the HPV genome and PCa (OR = 2.63, 95% C.I = 0.89-7.91, P-value = 0.078). Moreover, the HPV high-risk genotypes 16 and 18 were detected in 47.4% and 31.6% of HPV-infected PCa tissues, respectively. The expression level of the tumor suppressor proteins (Rb and p53) significantly decreased in the HPV-infected samples compared to the HPV negative specimens (P-value = 0.01, P-value = 0.01, respectively). However, the expression level of the anti-apoptotic mediators and those involved in angiogenesis and inflammation significantly increased in the HPV-infected PCa group compared to the HPV-negative PCa and control groups (P-value < 0.05, respectively).

CONCLUSION

Our study suggests that although it is not definitely known whether HPV causes PCa, this virus probably modulates PCa cell behavior by affecting inflammation, angiogenesis, and apoptosis mechanisms, which, in turn, promotes tumorigenesis.

MNX1 Promotes Malignant Progression of Cervical Cancer via Repressing the Transcription of p21cip1

Motor neuron and pancreas homeobox 1 (MNX1) is a development-related genes and has been found to be highly expressed in several cancers. However, its biological function in cervical cancer remains largely unexplored. QRT-PCR, western blot, and IHC showed that MNX1 was abnormally overexpressed in cervical cancer tissues and cell lines. The high expression level of MNX1 correlated with poorer clinicopathologic characteristics in cervical cancer patients. Evaluated by RTCA (Real Time Cellular Analysis) proliferation assay, colony formation assay, EdU assay, transwell assay, and matrigel assay, we found that knockdown of MNX1 inhibited proliferation, migration and invasion of cervical cancer in vitro, while overexpression of MNX1 promoted malignant phenotype of cervical cancer. And subcutaneous xenograft model confirmed the malignant phenotype of MNX1 in vivo. Furthermore, flow cytometry, chromatin immunoprecipitation, and luciferase reporter assay indicated that MNX1 accelerated cell cycle transition by transcriptionally downregulating cyclin-dependent kinases p21^cip1. In summary, our study revealed that MNX1 exerted an oncogenic role in cervical cancer via repressing the transcription of p21^cip1 and thus accelerating cell cycle progression. Our results suggested that MNX1 was a potential diagnostic marker and therapeutic target for cervical cancer patients.

Saikosaponin D inhibits proliferation of human osteosarcoma cells via the p53 signaling pathway

Saikosaponin D (SSd), the major monomeric terpenoid extracted from Radix bupleuri, a traditional Chinese medicinal herb, exerts various pharmacological properties, including antitumor, anti-inflammatory and antiviral. The present study aimed to investigate the role of SSd in human osteosarcoma (OS) cell growth. In the investigation MTS and EdU assays were applied and flow cytometric analyses of cell cycle and apoptosis were performed. Western blotting and reverse transcription-quantitative polymerase chain reaction analyses were used to explore the underlying mechanisms of SSd on cell cycle transition and p53 signaling. Here, it was demonstrated that SSd administration at 80 µmol/l significantly inhibited 143B and MG-63 proliferation. Furthermore, SSd significantly increased the percentage of 143B and MG-63 cells in G₀-G₁ phase and the number of apoptosis cells compared with the control group. Data further demonstrated that SSd treatment upregulated mRNA and protein levels of tumor protein 53 (p53) and its downstream targets, including p21, p27, B-cell lymphoma-2-like protein 4 and cleaved caspase-3, and downregulated mRNA and protein levels of cyclinD1. The results suggested that SSd was a functional tumor suppressor and inhibited OS proliferation via activation of the p53 signaling pathway and may be used in the treatment of osteosarcoma in future.

Lymphocyte subsets predictive value and possible involvement of human papilloma virus infection on breast cancer molecular subtypes

AIM

To detect human papilloma virus (HPV) presence and to characterize cellular immune response in breast cancer patients.

METHODS

A total of 74 women were included, of which 48 samples were from patients diagnosed with breast cancer and 26 patients with benign pathology of the breast. Molecular subtype classification was performed based on the immunohistochemical reports of the tumor piece. HPV genome detection and genotyping from fresh breast biopsies was performed using the INNO-LIPA HPV Genotyping Extra test (Innogenetics, Ghent, Belgium). CD3+, CD4+, CD8+ and natural killer (NK)+ cells levels from peripheral blood samples from patients with breast cancer and benign pathology were measured by flow cytometry.

RESULTS

Luminal A was the most frequent breast cancer molecular subtype (33.33%). HPV was detected in 25% of the breast cancer patients, and genotype 18 was the most frequent in the studied population. The mean of CD3+, CD4+ and CD8+ subpopulations were decreased in patients with breast cancer, in relation to those with benign pathology, with a statistically significant difference in CD8+ values (P = 0.048). The mean of NK+ cells was increased in the benign pathology group. The average level of CD3+, CD4+, CD8+ and NK+ cells decreased as the disease progressed. HER2+ and Luminal B HER2+ tumors had the lowest counts of cell subsets. HPV breast cancer patients had elevated counts of cellular subsets.

CONCLUSION

Determining level changes in cellular subsets in breast cancer patients is a useful tool to evaluate treatment response.

High-Risk Human Papillomaviral Oncogenes E6 and E7 Target Key Cellular Pathways to Achieve Oncogenesis

Infection with high-risk human papillomavirus (HPV) has been linked to several human cancers, the most prominent of which is cervical cancer. The integration of the viral genome into the host genome is one of the manners in which the viral oncogenes E6 and E7 achieve persistent expression. The most well-studied cellular targets of the viral oncogenes E6 and E7 are p53 and pRb, respectively. However, recent research has demonstrated the ability of these two viral factors to target many more cellular factors, including proteins which regulate epigenetic marks and splicing changes in the cell. These have the ability to exert a global change, which eventually culminates to uncontrolled proliferation and carcinogenesis.

Epstein-Barr Virus and Human Papillomaviruses Interactions and Their Roles in the Initiation of Epithelial-Mesenchymal Transition and Cancer Progression

Oncoviruses are implicated in around 20% of all human cancers including both solid and non-solid malignancies. Epstein–Barr virus (EBV) and human papillomaviruses (HPVs) are the most common oncoviruses worldwide. Currently, it is well established that onco-proteins of EBV (LMP1, LMP2A, and EBNA1) and high-risk HPVs (E5 and E6/E7) play an important role in the initiation and/or progression of several human carcinomas, including cervical, oral, and breast. More significantly, it has been recently pointed out that viral onco-proteins of EBV and high-risk HPVs can be co-present and consequently cooperate to initiate and/or amplify epithelial–mesenchymal transition (EMT), which is the hallmark of cancer progression and metastasis. This could occur by β-catenin, JAK/STAT/SRC, PI3k/Akt/mTOR, and/or RAS/MEK/ERK signaling pathways, which onco-proteins of EBV and HPVs share. This review presents the most recent advances related to EBV and high-risk HPVs onco-proteins interactions and their roles in the progression of human carcinomas especially oral and breast via the initiation of EMT.