No link between viral findings in the prostate and subsequent cancer development

Unveiling the Impact of Epstein-Barr Virus on the Risk of Prostate Cancer: A Mendelian Randomization Study

Given the consistent detection of Epstein-Barr virus (EBV) in prostate tissues and the clinical evidence suggesting its involvement in prostate cancer (PCa), the potential association between EBV infection and PCa warrants further investigation. This study aimed to assess the causal relationship between EBV infection and PCa using Mendelian randomization (MR). We utilized data from a publicly available genome-wide association study (GWAS) on PCa, alongside data on five serum anti-EBV virus-related antibodies. Our findings indicate a potential causal link between serum EBV EA-D antibody levels and an increased risk of PCa. These results highlight the need for additional research to elucidate the mechanisms by which EBV may contribute to the progression of PCa, potentially offering new insights into its pathogenesis and therapeutic targets.

Comparative Study Analysis of Epstein-Barr Virus Infection: Tissue Versus Blood Samples in Patients With Prostatic Adenocarcinoma and Its Correlation With Clinicopathological Parameters

Prostate cancer (PCa) is the most frequently diagnosed cancer and a leading cause of cancer-related mortality in men. The diagnosis and treatment of PCa carry considerable medical, psychological, and economic implications. Among the risk factors contributing to cancer, viral infections, notably Epstein-Barr virus (EBV), play a significant role. It is recognized as an oncogenic virus associated with various lymphomas, nasopharyngeal carcinomas, and breast cancer cases but its role in PCa remains unclear. This study aims to contrast the prevalence of EBV in blood and tissue samples of PCa patients and assess its correlation with tumor clinicopathological criteria. In this prospective study, 50 fresh biopsies and 50 blood samples were collected from patients with a confirmed diagnosis of PCa. EBV DNA was detected using polymerase chain reaction (PCR). A statistical analysis was then conducted to examine the correlation between EBV prevalence and PCa clinicopathological characteristics. EBV DNA was detected in 38% of PCa blood samples and 64% of PCa tissue samples, with a higher prevalence in tissue samples (p = 0.009). The statistical analysis revealed a significant correlation between EBV infection and pathological Gleason score (p = 0.041) in PCa tissue, as well as pathological T-stage (p = 0.02) in PCa blood. The results show that patients with PCa have higher levels of EBV in their tissues than in their blood, suggesting that EBV may play an important role in the etiology of PCa. This paves the way for further research into the function of EBV as a potential biomarker in the development and progression of prostate carcinoma in order to combat oncogenic viruses.

Can the Epstein-Barr Virus Play a Role in the Development of Prostate Cancer?

Prostate cancer (PCa) is the fourth most frequently diagnosed cancer worldwide, accounting for 7.3% of all cancers. PCa mortality is the fifth most common cause of cancer death. Despite well-known factors influencing the development of PCa, such as age, race/ethnicity and family history, many researchers have raised the possibility of persistent infections with oncogenic viruses. Therefore, we aimed to assess the frequency of Epstein-Barr virus (EBV) DNA in tissue collected from PCa patients. Next, the frequency and the level of Epstein-Barr virus capsid antigen (EBVCA) and Epstein-Barr nuclear antigen 1 (EBNA1) antibodies in both IgA and IgG classes were measured. The antibody titer was also analyzed depending on the risk group, Gleason score (GS) and tumor, node, metastasis (TNM) classification. Serum samples were analyzed using the Microblot-Array EBV IgM, IgA and IgG test kits. The study group consisted of 115 patients diagnosed and histopathologically confirmed with PCa. In 49% of patients included in the study, EBV DNA was detected in the tumor tissue. The studies showed both higher seroprevalence and higher antibody titers in patients with EBV-positive PCa compared to patients with EBV-negative PCa. We also observed a dependence of antibody titer on pathological features, such as GS, risk group and T stage.

Polyploid Giant Cancer Cells Generated from Human Cytomegalovirus-Infected Prostate Epithelial Cells

BACKGROUND

Prostate cancer is the most commonly diagnosed malignancy and the sixth leading cause of cancer death in men worldwide. Chromosomal instability (CIN) and polyploid giant cancer cells (PGCCs) have been considered predominant hallmarks of cancer. Recent clinical studies have proven the association of CIN, aneuploidy, and PGCCs with poor prognosis of prostate cancer (PCa). Evidence of HCMV transforming potential might indicate that HCMV may be involved in PCa.

METHODS

Herein, we underline the role of the high-risk HCMV-DB and -BL clinical strains in transforming prostate epithelial cells and assess the molecular and cellular oncogenic processes associated with PCa.

RESULTS

Oncogenesis parallels a sustained growth of "CMV-Transformed Prostate epithelial cells" or CTP cells that highly express Myc and EZH2, forming soft agar colonies and displaying stemness as well as mesenchymal features, hence promoting EMT as well as PGCCs and a spheroid appearance.

CONCLUSIONS

HCMV-induced Myc and EZH2 upregulation coupled with stemness and EMT traits in IE1-expressing CTP might highlight the potential role of HCMV in PCa development and encourage the use of anti-EZH2 and anti-HCMV in PCa treatment.

Human papillomavirus and prostate cancer: systematic review and meta-analysis

The involvement of human papillomavirus (HPV) in the prostate carcinogenesis is a controversial issue. The presented meta-analysis was carried out to systematize the currently available research results regarding this question. The meta-analysis includes case-control studies from 1991 to 2022, which were collected from publicly available bibliometric databases. The meta-analysis was performed using Meta-Essentials_1.5 software. We used Begg's and Egger's methods to assess publication bias. Cochran's Q test was used to assess heterogeneity and the I2 index was employed for calculating the variation in the pooled estimations. The analysis was based on data from 27 case-control studies, which in total yielded 1607 tumour tissue samples of prostate and 1515 control samples (317 samples of normal tissue, 1198 samples of benign prostatic hyperplasia (BPH)). According to the data obtained, there was high risk of prostate cancer by HPV infection in both cases. HPV was found in prostate cancer in 25.8% of cases, while in normal tissue samples the virus was detected in 9.2% of cases and in 17.4% with BPH as a control. In particular, more studies on the association of HPV and prostate cancer are needed to prove the role of HPV in the development of prostate cancer. In addition to the controversial question of whether HPV infection is associated with prostate cancer risk, it is worth considering whether the samples used as a control have an impact on the results. The impact of HPV in prostate tumour tissue samples on outcome should also be investigated.

Does Human Papillomavirus Play a Causative Role in Prostate Cancer? A Systematic Review Using Bradford Hill's Criteria

Globally, prostate cancer is the fifth most common cause of cancer-related death among men, and metastatic castration-resistant prostate cancer has a high cancer-related mortality rate. However, the aetiology of this disease is not yet fully understood. While human papillomavirus (HPV) has been associated with several types of cancer, including cervical, anal, and oropharyngeal cancers, studies investigating the relationship between HPV and prostate cancer have shown mixed results. This systematic review aimed to evaluate the causative association between HPV and prostate cancer using Bradford Hill's criteria. A comprehensive search of PubMed was conducted, and 60 out of 482 studies were included in the review. The included studies were evaluated based on nine Bradford Hill criteria, and information on the identification and transmission of the virus and potential oncogenic mechanisms was also extracted. The strength of association criterion was not met, and other criteria, such as consistency and coherence, were not fulfilled. However, biological plausibility was supported, and potential oncogenic mechanisms were identified. While some studies have reported the presence of HPV in prostate cancer tissues, the overall quality of evidence remains low, and the association between HPV and prostate cancer is weak. Nevertheless, the prostate is a potential reservoir for the transmission of HPV, and the HPV E6 and E7 oncoproteins and inflammation are likely to be involved in any oncogenic mechanisms. Further studies with a higher level of evidence are needed to establish a definitive link between HPV and prostate cancer.

Is Candida albicans a contributor to cancer? A critical review based on the current evidence

The association between Candida albicans (C. albicans) and cancer has been noticed for decades. Whether C. albicans infection is a complication of cancer status or as a contributor to cancer development remains to be discussed. This review systematically summarized the up-to-date knowledge about associations between C. albicans and various types of cancer, and discussed the role of C. albicans in cancer development. Most of the current clinical and animal evidence support the relationship between C. albicans and oral cancer development. However, there is insufficient evidence to demonstrate the role of C. albicans in other types of cancer. Moreover, this review explored the underlying mechanisms for C. albicans promoting cancer. It was hypothesized that C. albicans may promote cancer progression by producing carcinogenic metabolites, inducing chronic inflammation, remodeling immune microenvironment, activating pro-cancer signals, and synergizing with bacteria.

Detection and characterization of latency stage of EBV and histopathological analysis of prostatic adenocarcinoma tissues

The pathophysiology of prostate cancer involves both genetic and acquired factors, including pathogens, such as viruses. A limited number of studies have shown the presence of Epstein-Barr virus (EBV) in prostate cancer tissues. However, there is a dearth of data exploring EBV latency profile in prostate cancer, and the relationship of EBV with histopathological features of prostate cancer. In this study, prostate cancer and benign prostatic hyperplasia (BPH) samples were screened for the presence of EBV, followed by the characterization of the EBV latency profile and analysis of histopathological parameters in EBV-positive and EBV-negative groups. A conventional PCR strategy was employed using virus-specific primers to screen EBV in 99 formalin-fixed paraffin-embedded (FFPE) prostate cancer and 33 BPH samples received for histopathological analysis during the years 2019-2020. Subsequently, cDNA samples were used in a qPCR array to analyze the expression of EBV latency-associated genes to map the latency profile EBV maintains in the samples. Finally, statistical analyses were performed to determine the correlation between EBV and several histopathological features of the samples. EBV was detected in 39% of prostate cancer and 24% of BPH samples. The histopathological analysis of prostate cancer samples identified all samples as prostatic adenocarcinoma of acinar type, while statistical analyses revealed EBV-positive samples to exhibit significantly higher (p < 0.05) Gleason major and total Gleason scores as compared to EBV-negative samples. In the EBV-positive samples, variable expression patterns of latency-associated genes were observed, where most of the samples exhibited EBV latency II/III-like profiles in prostate cancer, while latency-II-like profiles in BPH samples. This study suggests a high prevalence of EBV in prostate samples, where EBV exhibited latency II/III-like profiles. Furthermore, EBV-positive samples exhibited a higher Gleason score suggesting a possible link between EBV and the onset/progression of prostate cancers. However, future functional studies are required to understand the role of the EBV gene expression profile in the onset/progression of prostate cancer.

Multiple pathogens and prostate cancer

BACKGROUND

The aim of this review is to consider whether multiple pathogens have roles in prostate cancer.

METHODS

We have reviewed case control studies in which infectious pathogens in prostate cancer were compared to normal and benign prostate tissues. We also reviewed additional evidence from relevant published articles.

RESULTS

We confirmed that high risk human papilloma viruses are a probable cause of prostate cancer. We judged Escherichia coli, Cutibacterium acnes, Neisseria gonorrhoea, Herpes simplex, Epstein Barr virus and Mycoplasmas as each having possible but unproven roles in chronic prostatic inflammation and prostate cancer. We judged Cytomegalovirus, Chlamydia trachomatis, Trichomonas vaginalis and the Polyoma viruses as possible but unlikely to have a role in prostate cancer.

CONCLUSIONS AND ACTIONS

The most influential cause of prostate cancer appears to be infection induced chronic inflammation. Given the high prevalence of prostate cancer it is important for action to can be taken without waiting for additional conclusive evidence. These include: 1. Encouragement of all boys (as well as girls) to have HPV vaccines 2. The vigorous use of antibiotics to treat all bacterial pathogens identified in the urogenital tract 3. The use of antiviral medications to control herpes infections 4. Education about safe sexual practices.

Human herpesvirus 8 infection is associated with prostate cancer among IFNL4-ΔG carriers

Background

The dinucleotide germline variant, rs368234815-ΔG, in the IFNL4 gene (IFNL4-ΔG) has been associated with prostate cancer among men at increased risk of sexually transmitted infections and reported to impair viral clearance. Human herpesvirus 8 (HHV-8) seropositivity has been associated with prostate cancer in Tobago.

Methods

We examined whether the association of HHV-8 with prostate cancer is IFNL4-ΔG-dependent among 728 IFNL4-ΔG-genotyped cases and 813 genotyped population-based controls from the NCI-Maryland Prostate Cancer Case-Control study. Associations between HHV-8 and prostate cancer were assessed in multivariable unconditional logistic regression models. We calculated adjusted odds ratios (OR) and stratified the analysis into men harboring the IFNL4-ΔG-variant and non-carriers (ΔG/ΔG or ΔG/TT vs. TT/TT).

Results

HHV-8 seropositivity was higher in cases than controls (11% vs. 6%) and this association was restricted to carriers of the ΔG allele (OR 2.19: 95% CI:1.38–3.48) in both African American (OR 1.96; 95% CI:1.08–3.56) and European American men (OR 2.59; 95% CI:1.20–5.56).

Conclusions

HHV-8 seropositivity is associated with increased odds of prostate cancer in men harboring the IFNL4 rs368234815-ΔG variant. This study describes HHV-8 infection as a candidate prostate cancer risk factor in men with the IFNL4-ΔG genotype and supports the hypothesis that IFNL4-ΔG is a susceptibility factor that contributes to prostate cancer.

JC Polyoma Virus as a Possible Risk Factor for Prostate Cancer Development - Immunofluorescence and Molecular Based Case Control Study

BACKGROUND

In vitro studies have produced conflicting results about the significance of the JC Polyoma Virus (JCV) in the human cancers.

OBJECTIVES

Our study aims to detect the presence of JCV Large T antigen (LTag) together with viral load quantitation in the prostate tumor samples to assess if JCV harbors risk factor for prostate cancer (PCa).

METHOD

This was a case control-based study. A total of 110 patients participated in this study, including 55 patients with PCa and another 55 patients with benign prostatic hyperplasia (BPH) as cases and controls, respectively. Tissue, blood and urine samples were collected from each participant. Tissues samples were analyzed for the presence of JCV Ltag using a direct immunofluorescence assay (IF). Only positive IF tested samples were subjected to viral quantitation assay. Data were collected and managed using SPSS version 20.

RESULT

The JCV LTag in the cases group was 23.63% (13/55) which was higher than that of the controls group 5.45% (3/55) with a P. value of .006 and O.R of 5.76. The mean of viral load was significantly higher among cases tissue specimens 20156 ± 5450 copies/ml compared to controls group 6378 ± 2456copies/ml with P-value of .002. The virus was detected in 11/13 (84.6%) urine samples of cases with a mean viral load of 14068 ± 4590 copies/ml compared to 2/3 (66.6%) of controls viral load 2534 ± 1267 copies/ml.

CONCLUSION

In conclusion, a higher JCV LTag with more viral load were detected in cases group compared to controls. Our findings support a strong relationship between JCV infection and the probability of developing PCa.

Possible role of HPV/EBV coinfection in anoikis resistance and development in prostate cancer

BACKGROUND

This study aimed to evaluate the possible role of human papillomavirus (HPV) and Epstein-Barr virus (EBV) coinfection as an etiological factor for prostate cancer (PCa) development.

METHODS

This case-control study was conducted on 67 patients with PCa and 40 control subjects. The expression levels of cellular and viral factors involved in inflammation, tumor progression, and metastasis were quantified, using the enzyme-linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR) assay.

RESULTS

The EBV/HPV coinfection was reported in 14.9% of patients in the case group and 7.5% of the control subjects. The high-risk types of HPV, that is, HPV 16 and HPV 18, were responsible for 50 and 30% of HPV/EBV-coinfected PCa cases (n = 10), respectively. No significant relationship was observed between PCa and HPV/EBV coinfection (OR = 2.9, 95% CI: 0.18-45.2, P = 0.31). However, the highest percentage of HPV genome integration was found in the HPV/EBV-coinfected PCa group (8/10; 80%). Also, the mean expression levels of inflammatory factors (IL-17, IL-6, TNF-α, NF-κB, VEGF, ROS, and RNS), anti-apoptotic mediators (Bcl-2 and survivin), and anti-anoikis factors (Twist and N-cadherin) were significantly higher in the HPV/EBV-coinfected PCa group, compared to the non-coinfected PCa cases. Nevertheless, the tumor-suppressor proteins (p53 and pRb) and E-cadherin (inhibitor of anoikis resistance) showed significant downregulations in the HPV/EBV-coinfected PCa group, compared to the non-coinfected PCa cases.

CONCLUSION

The HPV/EBV coinfection may be an etiological factor for PCa through modulation of cellular behaviors.

Epstein-Barr and BK virus in cancerous and noncancerous prostate tissue

Aim: We conducted a case–control study to examine the presence of BK virus (BKV) and Epstein barr virus (EBV) genome in prostate specimens of benign prostatic hyperplasia (BPH) and prostate cancer (PCa) in Iran. Materials & methods: 64 paraffin-embedded PCa specimens were included as case subjects and 57 paraffin-embedded BPH specimens as control. DNA extraction was carried out by phenol–chloroform technique and PCR for detection of BKV and EBV. Results: 90 (73%) out of 121 specimens were collected by prostatectomy and 31 (27%) by transurethral resection of the prostate. BKV was not detected in any of the samples and one positive EBV was reported. Conclusion: These findings provide further evidence against a causative role of BKV and EBV in the development of PCa.

Lack of evidence of HPV etiology of prostate cancer following radical surgery and higher frequency of the Arg/Pro genotype in Turkish men with prostate cancer

Objectives

The aim of this study was to assess the possible role of HPV in the development of prostate cancer (PCa) and investigate the distribution of the p53 codon 72 polymorphism in PCa in a Turkish population.

Materials and methods

A total of 96 tissues, which had been obtained using a radical surgery method, formalin-fixed and parafin-embedded, were used in this study. The study group consisted of 60 PCa tissues (open radical prostatectomy) and the control group contained 36 benign prostatic hyperplasia tissues (BPH) (transvesical open prostatectomy). The presence of HPV and the p53 codon 72 polymorphism was investigated in both groups using real-time PCR and pyrosequencing.

Results

The results of the real-time PCR showed no HPV DNA in any of the 36 BPH tissue samples. HPV-DNA was positive in only 1 of the 60 PCa samples (1.7%). The HPV type of this sample was identified as HPV-57. The distribution of the three genotypes, Arg/Arg, Arg/Pro and Pro/Pro was found to be 45.6, 45.6, and 8.8% in the PCa group and 57.1%, 34.3% and 8.6% in the control group, respectively. Compared with the control group, patients with PCa had a higher frequency of the Arg/Pro genotype and Proline allele (odds ratio (OR)=1.67, 95% confidence interval (CI)=0.68-4.09, p=0.044; OR=1.13, 95% CI=0.76-1.68, p=0.021, respectively).

Conclusions

The results of the study do not support the hyphothesis that prostate cancer is associated with HPV infection but indicated that Proline allele can be a risk factor in the development of PCa in the Turkish population.

Insight into infection-mediated prostate damage: Contrasting patterns of C-reactive protein and prostate-specific antigen levels during infection

BACKGROUND

To investigate mechanisms underlying our previous observation of a large rise in serum prostate-specific antigen, a marker of prostate pathology, during both sexually transmitted and systemic infections, we measured serum high-sensitivity C-reactive protein (hsCRP), a marker of systemic inflammation, in our previous case-control study of young, male US military members and compared our findings to those for PSA.

METHODS

We measured hsCRP before and during infection for 299 chlamydia, 112 gonorrhea, and 59 non-chlamydial, non-gonococcal urethritis (NCNGU) cases; before and after infection for 55 infectious mononucleosis (IM) and 90 other systemic/non-genitourinary cases; and for 220-256 controls.

RESULTS

Only gonorrhea cases were significantly more likely to have a large hsCRP rise (≥1.40 mg/L or ≥239%) during infection than controls (P < 0.01). However, gonorrhea, IM, and other systemic/non-genitourinary cases were more likely to have a rise of any magnitude up to one year post-diagnosis than controls (p = 0.038-0.077).

CONCLUSIONS

These findings, which differ from those for PSA, suggest distinct mechanisms of elevation for hsCRP and PSA, and support both direct (eg, prostate infection) and indirect (eg, systemic inflammation-mediated prostate cell damage) mechanisms for PSA elevation. Future studies should explore our PSA findings further for their relevance to both prostate cancer screening and risk.

Lack of detection of human papillomavirus DNA in prostate carcinomas in patients from northeastern Brazil

Prostate cancer is the second most common cancer among men in western populations, and despite its high mortality, its etiology remains unknown. Inflammatory processes are related to the etiology of various types of tumors, and prostate inflammation, in particular, has been associated with prostate cancer carcinogenesis and progression. Human papillomavirus (HPV) is associated with benign and malignant lesions in the anogenital tract of both females and males. The possible role of HPV in prostate carcinogenesis is a subject of great controversy. In this study, we aimed to examine the prevalence of HPV infections in prostate carcinomas of patients from northeastern Brazil. This study included 104 tissue samples from primary prostate carcinoma cases. HPV DNA was purified and then amplified using MY09/11 and GP5+/GP6+ degenerate primer sets that detect a wide range of HPV types, and with specific PCR primers sets for E6 and E7 HPV regions to detect HPV 16. None of the samples showed amplification products of HPV DNA for primer sets MY09/11 and GP5+/GP6+, or the specific primer set for the E6 and E7 HPV regions. HPV infection, thus, does not seem to be one of the causes of prostate cancer in the population studied.

Co-infection of Epstein-Barr virus and human papillomavirus in human tumorigenesis

Viral infections contribute to approximately 12% of cancers worldwide, with the vast majority occurring in developing countries and areas. Two DNA viruses, Epstein-Barr virus (EBV) and human papillomavirus (HPV), are associated with 38% of all virus-associated cancers. The probability of one patient infected with these two distinct types of viruses is increasing. Here, we summarize the co-infection of EBV and HPV in human malignancies and address the possible mechanisms for the co-infection of EBV and HPV during tumorigenesis.

Infectious mononucleosis, other infections and prostate-specific antigen concentration as a marker of prostate involvement during infection

Although Epstein-Barr virus has been detected in prostate tissue, no associations have been observed with prostate cancer in the few studies conducted to date. One possible reason for these null findings may be use of cumulative exposure measures that do not inform the timing of infection, i.e., childhood versus adolescence/early adulthood when infection is more likely to manifest as infectious mononucleosis (IM). We sought to determine the influence of young adult-onset IM on the prostate by measuring prostate-specific antigen (PSA) as a marker of prostate inflammation/damage among U.S. military members. We defined IM cases as men diagnosed with IM from 1998 to 2003 (n = 55) and controls as men without an IM diagnosis (n = 255). We selected two archived serum specimens for each participant, the first collected after diagnosis for cases and one randomly selected from 1998 to 2003 for controls (index), as well as the preceding specimen (preindex). PSA was measured in each specimen. To explore the specificity of our findings for prostate as opposed to systemic inflammation, we performed a post hoc comparison of other infectious disease cases without genitourinary involvement (n = 90) and controls (n = 220). We found that IM cases were more likely to have a large PSA rise than controls (≥ 20 ng/mL: 19.7% versus 8.8%, p = 0.027; ≥ 40% rise: 25.7% versus 9.4%, p = 0.0021), as were other infectious disease cases (25.7% versus 14.0%, p = 0.020; 27.7% versus 18.0%, p = 0.092). These findings suggest that, in addition to rising because of prostate infection, PSA may also rise because of systemic inflammation, which could have implications for PSA interpretation in older men.

Human papillomavirus 16 infection as a potential risk factor for prostate cancer: an adaptive meta-analysis

OBJECTIVES

Although an expert review published in 2013 concluded that an association between human papillomavirus (HPV) infection and prostate cancer (PCa) risk had not yet been firmly established, a 2011 systematic review of 14 articles revealed an increased prevalence of HPV-16 DNA in PCa tissues. Another meta-analysis of the related articles is needed to evaluate the potential link between HPV infection and PCa risk.

METHODS

A snowballing search strategy was applied to the previously cited articles in the above-mentioned expert review and systematic review. Additional articles selected for this meta-analysis should fulfill all following inclusion criteria: (a) evaluation of detected HPV-16 DNA in tissue samples and the PCa risk and (b) report of the HPV-16 prevalence in both cancer and control tissues. Estimated summary odds ratios (sOR) with 95% confidence intervals (CI) were calculated using fixed effect or random-effect models.

RESULTS

Hand searching identified 16 new articles. The sOR of the total 30 articles indicated a significant HPV-16 infection-related increase in the PCa risk (sOR, 1.851; 95% CI, 1.353 to 2.532, I(2)=37.82%).

CONCLUSIONS

These facts provide additional supportive evidence for a causal role of HPV-16 infection in prostate carcinogenesis. As the PCa incidence rates have increased rapidly in Asian countries, including Korea, during the last several decades, further studies of HPV-related PCa carcinogenesis may be necessary.

Detection of human papillomavirus (HPV) DNA prevalence and p53 codon 72 (Arg72Pro) polymorphism in prostate cancer in a Greek group of patients

Prostate cancer is the most common neoplasm found in males and the second most frequent cause of cancer-related mortality in males in Greece. Among other pathogens, the detection frequency of human papillomavirus (HPV) has been found to be significantly increased in tumor tissues among patients with sexually transmitted diseases (STDs), depending on the geographical distribution of each population studied. The present study focused on the detection of HPV and the distribution of Arg72Pro p53 polymorphism in a cohort of healthy individuals, as well as prostate cancer patients. We investigated the presence of HPV in 50 paraffin-embedded prostate cancer tissues, as well as in 30 physiological tissue samples from healthy individuals by real-time PCR. Furthermore, the same group of patients was also screened for the presence of the Arg72Pro polymorphism of the p53 gene, a p53 polymorphism related to HPV. Out of the 30 control samples, only 1 was found positive for HPV (3.33 %). On the contrary, HPV DNA was detected in 8 out of the total 50 samples (16 %) in the prostate cancer samples. The distribution of the three genotypes, Arg/Arg, Arg/Pro, and Pro/Pro, was 69.6, 21.7, and 8.7 % in the cancer patients and 75.0, 17.86, and 7.14 % in healthy controls, respectively. No statistically significant association was observed between the HPV presence and the age, stage, p53 polymorphism status at codon 72, or PSA. The increased prevalence of HPV detected in the prostate cancer tissues is in agreement with that reported in previous studies, further supporting the association of HPV infection and prostate cancer.

Detection of infectious organisms in archival prostate cancer tissues

BACKGROUND

Seroepidemiological studies have reported associations between exposure to sexually transmitted organisms and prostate cancer risk. This study sought DNA evidence of candidate organisms in archival prostate cancer tissues with the aim of assessing if a subset of these cancers show any association with common genital infections.

METHODS

221 archival paraffin-embedded tissue blocks representing 128 histopathologically confirmed prostate cancers comprising 52 "aggressive" (Gleason score ≥ 7) and 76 "non-aggressive" (Gleason score ≤ 6) TURP or radical prostatectomy specimens were examined, as well as unaffected adjacent tissue when available. Representative tissue sections were subjected to DNA extraction, quality tested and screened by PCR for HSV-1, HSV-2, XMRV, BKV, HPV, Chlamydia trachomatis, Ureaplasma parvum, Ureaplasma urealyticum, Mycoplasma genitalium, and Trichomonas vaginalis.

RESULTS

195 of 221 DNA samples representing 49 "aggressive" and 66 "non-aggressive" prostate cancer cases were suitable for analysis after DNA quality assessment. Overall, 12.2% (6/49) aggressive and 7.6% (5/66) non-aggressive cases were positive for any of the candidate organisms. Mycoplasma genitalium DNA was detected in 4/66 non-aggressive, 5/49 aggressive cancers and in one cancer-unaffected adjacent tissue block of an aggressive case. Ureaplasma urealyticum DNA was detected in 0/66 non-aggressive and 1/49 aggressive cancers and HSV DNA in 1/66 non-aggressive and 0/49 aggressive cancers. This study did not detect BKV, XMRV, T. vaginalis, U. parvum, C. trachomatis or HPV DNA.

CONCLUSIONS

The low prevalence of detectable microbial DNA makes it unlikely that persistent infection by the selected candidate microorganisms contribute to prostate cancer risk, regardless of tumour phenotype.

Are human polyomaviruses co-factors for cancers induced by other oncoviruses?

Presently, 12 human polyomaviruses are known: BK polyomavirus (BKPyV), JCPyV, KIPyV, WUPyV, Merkel cell polyomavirus (MCPyV), HPyV6, HPyV7, Trichodysplasia spinulosa-associated polyomavirus, HPyV9, HPyV10, STLPyV and HPyV12. In addition, the non-human primate polyomavirus simian virus 40 (SV40) seems to circulate in the human population. MCPyV was first described in 2008 and is now accepted to be an etiological factor in about 80% of the rare but aggressive skin cancer Merkel cell carcinoma. SV40, BKPyV and JCPyV or part of their genomes can transform cells, including human cells, and induce tumours in animal models. Moreover, DNA and RNA sequences and proteins of these three viruses have been discovered in tumour tissue. Despite these observations, their role in cancer remains controversial. So far, an association between cancer and the other human polyomaviruses is lacking. Because human polyomavirus DNA has been found in a broad spectrum of cell types, simultaneous dwelling with other oncogenic viruses is possible. Co-infecting human polyomaviruses may therefore act as a co-factor in the development of cancer, including those induced by other oncoviruses. Reviewing studies that report co-infection with human polyomaviruses and other tumour viruses in cancer tissue fail to detect a clear link between co-infection and cancer. Directions for future studies to elaborate on a possible auxiliary role of human polyomaviruses in cancer are suggested, and the mechanisms by which human polyomaviruses may synergize with other viruses in oncogenic transformation are discussed.

The role of human papilloma virus (HPV) infection in non-anogenital cancer and the promise of immunotherapy: a review

Over the past 30 years, human papilloma virus (HPV) has been shown to play a role in the development of various cancers. Most notably, HPV has been linked to malignant progression in neoplasms of the anogenital region. However, high-risk HPV has also been suggested to play a significant role in the development of cancers in other anatomic locations, such as the head and neck, lung, breast and bladder. In 2006, the first vaccine for HPV, Gardasil, was approved for the prevention of subtypes 6, 11, 16 and 18. A few years later, Cevarix was approved for the prevention of subtypes 16 and 18, the HPV subtypes most frequently implicated in malignant progression. Although increased awareness and vaccination could drastically decrease the incidence of HPV-positive cancers, these approaches do not benefit patients who have already contracted HPV and developed cancer as a result. For this reason, researchers need to continue developing treatment modalities, such as targeted immunotherapies, for HPV-positive lesions. Here, we review the potential evidence linking HPV infection with the development of non-anogenital cancers and the potential role of immunotherapy in the prevention and eradication of HPV infection and its oncogenic sequela.

MSMB variation and prostate cancer risk: clues towards a possible fungal etiology

BACKGROUND. With recent advances in high-throughput sequencing technologies, many prostate cancer risk loci have been identified, including rs10993994, a single nucleotide polymorphism (SNP) located near the MSMB gene. Variant allele (T) carriers of this SNP produce less prostate secretory protein 94 (PSP94), the protein product of MSMB, and have an increased risk of prostate cancer (approximately 25% per T allele), suggesting that PSP94 plays a protective role in prostate carcinogenesis, although the mechanisms for such protection are unclear. METHODS. We reviewed the literature on possible mechanisms for PSP94 protection for prostate cancer. RESULTS. One possible mechanism is tumor suppression, as PSP94 has been observed to inhibit cell or tumor growth in in vitro and in vivo models. Another novel mechanism, which we propose in this review article, is that PSP94 may protect against prostate cancer by preventing or limiting an intracellular fungal infection in the prostate. This mechanism is based on the recent discovery of PSP94's fungicidal activity in low-calcium environments (such as the cytosol of epithelial cells), and accumulating evidence suggesting a role for inflammation in prostate carcinogenesis. We provide further details of our proposed mechanism in this review article. CONCLUSIONS. To explore this mechanism, future studies should consider screening prostate specimens for fungi using the rapidly expanding number of molecular techniques capable of identifying infectious agents from the entire tree of life.

Polyomavirus BK and prostate cancer: an unworthy scientific effort?

The Polyomavirus BK (BKV) has been proposed to be one of the possible co-factors in the genesis of prostate cancer (PCa) but, so far, the only convincing suggestion is the hypothesis of a “hit and run” carcinogenic mechanism induced by the virus at early stages of this disease. To support this hypothesis we conducted an updated systematic review on previous studies regarding the association between BKV and PCa, in order to interpret the contrasting results and to explore whether there might be a significant virus-disease link. This updated analysis provides evidence for a significant link between BKV expression and PCa development, particularly between the BKV infection and the cancer risk. Forthcoming scientific efforts that take cue from this study might overcome the atavistic and fruitless debate regarding the BKV-PCa association.

Evidence supporting the association of polyomavirus BK genome with prostate cancer

Prostate cancer (PCA) is the most frequent cancer in men. Exposure to infectious agents has been reported to have a putative role in tumorigenesis. Among the infectious agents, convincing evidence has been accumulated about the human polyomavirus BK (BKV). Tissue fresh specimens, serum, and urine samples were collected from 124 consecutive patients, 56 with PCA and 68 with benign prostatic hyperplasia (BPH). Quantitative PCR assays were used to assess the presence of BKV and JC virus (JCV) genomes. BKV-positive tissue specimens were found in 32.1 and 22.1 % of PCA and BPH patients, respectively; in PCA group the number of positive BKV specimens/patients was significantly higher than in BPH group (3.06 vs. 1.73, p = 0.02). JCV genome was found in the biopsies collected from 28.1 and 24.2 % of PCA and BPH patients, respectively, with no significant difference in the rate of JCV specimens/patients between PCA and BPH groups. Our results support the putative causal association between BKV genome and PCA. Further studies are required to demonstrate the direct pathogenetic role of BKV in the PCA occurrence and progression in order to clear the tempting way of vaccine prophylaxis.

Human papillomavirus and Epstein Barr virus in prostate cancer: Koilocytes indicate potential oncogenic influences of human papillomavirus in prostate cancer

INTRODUCTION

The purpose of this study is to determine if high risk human papillomaviruses (HPV) and Epstein Barr virus (EBV) are both present in the same prostate cancer specimens.

METHODS

We used a range of analytical techniques including in situ polymerase chain reaction (IS-PCR) and standard liquid PCR followed by sequencing of the product to seek to identify HPV and EBV in normal, benign, and malignant prostate tissues.

RESULTS

Both HPV type 18 and EBV gene sequences were identified in a high and approximately equal proportion of normal, benign, and prostate cancer specimens. These sequences were located in the nuclei of prostate epithelial cells. HPV associated koilocytes were identified in 24% of prostate cancer specimens.

CONCLUSIONS

The presence of both HPV and EBV gene sequences in most of the same normal, benign, and malignant prostate specimens is particularly noteworthy because of recent experimental evidence demonstrating that EBV and HPV can collaborate to increase proliferation of cultured cervical cells. Because the presence of EBV and HPV in normal, benign, and malignant prostate tissues appears to be ubiquitous, it is possible that they are harmless. On the other hand HPV type 18 in particular, has high oncogenic potential and may be associated with some prostate cancers. The identification of HPV associated koilocytes in prostate cancer specimens is an indication of HPV infection and potential oncogenic influences of human papillomavirus in prostate cancer.

Prospective study of cytomegalovirus serostatus and prostate cancer risk in the Prostate Cancer Prevention Trial

PURPOSE

To investigate serologic evidence of infection by cytomegalovirus (CMV), a herpesvirus with known oncogenic potential that has been detected in malignant prostate tissue, in relation to prostate cancer (PCa) risk in a large case-control study nested in the Prostate Cancer Prevention Trial (PCPT).

METHODS

Cases were men with a confirmed diagnosis of PCa after visit 2 (n = 614), and controls were men not diagnosed with PCa during the trial who also had a negative end-of-study biopsy (n = 616). Controls were frequency-matched to cases by age, treatment arm, and family history of PCa. Sera from visit 2 were tested for CMV IgG antibodies.

RESULTS

No association was observed between CMV serostatus and PCa risk (adjusted CMV seroprevalence = 67.9 % for cases and 65.2 % for controls, odds ratio = 1.13, 95 % CI 0.89-1.45).

CONCLUSIONS

Considering our null findings in the context of the full CMV literature, CMV infection, as measured by serostatus, does not appear to increase PCa risk.

Differential patterns of large tumor antigen-specific immune responsiveness in patients with BK polyomavirus-positive prostate cancer or benign prostatic hyperplasia

The role of the polyomavirus BK (BKV) large tumor antigen (L-Tag) as a target of immune response in patients with prostate cancer (PCa) has not been investigated thus far. In this study, we comparatively analyzed humoral and cellular L-Tag-specific responsiveness in age-matched patients bearing PCa or benign prostatic hyperplasia, expressing or not expressing BKV L-Tag-specific sequences in their tissue specimens, and in non-age-matched healthy individuals. Furthermore, results from patients with PCa were correlated to 5-year follow-up clinical data focusing on evidence of biochemical recurrence (BR) after surgery (prostate specific antigen level of ≥0.2 ng/ml). In peripheral blood mononuclear cells (PBMC) from patients with PCa with evidence of BR and BKV L-Tag-positive tumors, stimulation with peptides derived from the BKV L-Tag but not those derived from Epstein-Barr virus, influenza virus, or cytomegalovirus induced a peculiar cytokine gene expression profile, characterized by high expression of interleukin-10 (IL-10) and transforming growth factor β1 and low expression of gamma interferon genes. This pattern was confirmed by protein secretion data and correlated with high levels of anti-BKV L-Tag IgG. Furthermore, in PBMC from these PCa-bearing patients, L-Tag-derived peptides significantly expanded an IL-10-secreting CD4(+) CD25(+(high)) CD127(-) FoxP3(+) T cell population with an effector memory phenotype (CD103(+)) capable of inhibiting proliferation of autologous anti-CD3/CD28-triggered CD4(+) CD25(-) T cells. Collectively, our findings indicate that potentially tolerogenic features of L-Tag-specific immune response are significantly associated with tumor progression in patients with BKV(+) PCa.

Thirty years of research on infection and prostate cancer: no conclusive evidence for a link. A systematic review

BACKGROUND

The potential role of genitourinary infection in the etiology of prostate cancer (CaP) has been extensively investigated for 30 years. Two basic approaches have been used: tissue-based methods (polymerase chain reaction, immunohistochemistry, and in situ hybridization) and serologic assays (enzyme-linked immunosorbent assay, immunofluorescence, etc.). The objective of this review was to answer the question of whether infection of the male genitourinary tract may have a role in the etiology of CaP.

MATERIALS AND METHODS

We have carried out a systematic review of the evidence that was published in the MEDLINE/PubMed database until December 2011. The search terms included "prostate cancer," "infection," and the explicit names of the various infectious agents. Additional studies were identified using a reference search. A total of 74 papers were included in the review, which cover the following infectious agents: human papillomavirus, cytomegalovirus, herpes simplex virus, Epstein-Barr virus, human herpesvirus, BK virus, JC virus, chlamydia, mycoplasma, ureaplasma, trichomonas, neisseria, treponema, Propionibacterium acnes, xenotropic murine leukemia virus-related virus and Candida albicans.

RESULTS

Despite the variable study designs and methodological approaches that were used, most of the pathogens that were studied were unlikely to be directly involved in prostate carcinogenesis.

CONCLUSIONS

The role of infection in the etiology of CaP has yet to be determined despite 30 years of research efforts. A discovery of an infectious agent that is associated with CaP would be of great medical importance; however, such a link would have to be firmly established before impacting on patient care.

Human papillomavirus 16 or 18 infection and prostate cancer risk: a meta-analysis

OBJECTIVE

Whether the oncogenic human papillomavirus (HPV) infection, especially infection with the most common subtypes 16 or 18, is related to prostate carcinogenesis remains conflicting. A meta-analysis with updated data was performed to obtain a more precise estimate of the association between them.

METHODS

Eligible studies were retrieved via both computer searches and review of references. The relation of HPV-16 or HPV-18 infection to prostate cancer (PC) was quantified separately. Stratified analyses based on HPV detection methods and geographic regions were also performed. Estimates of OR with 95% CI were summarized using the fixed-effect or random-effect models as appropriate.

RESULTS

Twenty-five eligible studies were retrieved. All the 25 studies were assigned for exploring the relation of HPV-16 infection to PC, while 13 studies provided additional information on HPV-18 simultaneously. In the overall estimates, the pooled OR indicated no significant increase of PC risk related with either HPV-16 (OR 1.09; 95% CI 0.97-1.23; P(heterogeneity) = 0.135) or HPV-18 (OR 1.05; 95% CI 0.89-1.24; P(heterogeneity) = 0.314) infection. Further quantitative assay of stratified data could also not yield any significant result, except the stratified analysis on HPV-16 DNA detection, which revealed higher HPV-16 DNA prevalence in PC cases (OR 1.54; 95% CI 1.07-2.20; P(heterogeneity) = 0.130).

CONCLUSIONS

Even though the overall estimates did not provide a supportive evidence for the causal role of HPV in prostate carcinogenesis, higher HPV-16 DNA prevalence in PC cases from the stratified analysis still indicated a potential association between HPV infection and PC risk in our meta-analysis.

Sexually transmitted infections and risk of prostate cancer: review of historical and emerging hypotheses

Since the early 1950s when sexually transmitted infections (STIs) were first proposed as a possible risk factor for prostate cancer, numerous epidemiologic studies have been conducted. Initially, these studies were primarily small case-control studies with retrospective, self-reported assessments of a narrow range of STIs, typically either any STIs, or gonorrhea and syphilis. However, as new STIs have been discovered/recognized, new and better tests to detect histories of STIs have been developed, and new resources for prostate cancer research have been created, epidemiologic studies have expanded to include a wide range of STIs, and have moved towards more rigorous, prospective study designs and serological assessment of STI histories. The results of these studies are reviewed and discussed, as well as possible new avenues of research, such as Trichomonas vaginalis infection and infections not typically considered to be sexually transmitted.

The role of human papillomavirus infection in prostate carcinoma

Human papillomavirus (HPV) infections are associated with benign and malignant lesions of the female and male anogenital tract. Currently the possible role of HPV infections in prostate carcinogenesis is a subject of great controversy. In this study we aimed to investigate the role of HPV infection in prostate carcinoma (PCa). The study included formalin-fixed paraffin-embedded tissue samples of 104 primary prostate adenocarcinoma cases and 104 control tissues of benign prostatic hyperplasia (BPH). HPV-DNA was purified and amplified through MY09/MY11 and GP5(+)/GP6(+) primers and subsequently subjected to sequencing. HPV-DNA was found in 13 of 104 (12.5%) PCa and 8 of 104 (7.7%) BPH samples. High-risk HPVs were detected in 10 of 13 (76.9%) PCa and 5 of 8 (62.5%) BPH samples with positive HPV-DNA. Low-risk HPVs were detected in 3 of 13 (23.1%) PCa and 3 of 8 (37.5%) BPH specimens with positive HPV-DNA. There was no significant difference between PCa and BPH specimens regarding HPV-DNA presence or the detection of high-risk and low-risk types of HPV. Our data do not support the role of HPV infection in prostate carcinoma. Further studies are required to elucidate the role of HPV infection in human prostate carcinogenesis.

Identification of viral infections in the prostate and evaluation of their association with cancer

Background

Several viruses with known oncogenic potential infect prostate tissue, among these are the polyomaviruses BKV, JCV, and SV40; human papillomaviruses (HPVs), and human cytomegalovirus (HCMV) infections. Recently, the Xenotropic Murine Leukemia Virus-related gammaretrovirus (XMRV) was identified in prostate tissue with a high prevalence observed in prostate cancer (PC) patients homozygous for the glutamine variant of the RNASEL protein (462Q/Q). Association studies with the R462Q allele and non-XMRV viruses have not been reported. We assessed associations between prostate cancer, prostate viral infections, and the RNASEL 462Q allele in Mexican cancer patients and controls.

Methods

130 subjects (55 prostate cancer cases and 75 controls) were enrolled in the study. DNA and RNA isolated from prostate tissues were screened for the presence of viral genomes. Genotyping of the RNASEL R462Q variant was performed by Taqman method.

Results

R/R, R/Q, and Q/Q frequencies for R462Q were 0.62, 0.38, and 0.0 for PC cases and 0.69, 0.24, and 0.07 for controls, respectively. HPV sequences were detected in 11 (20.0%) cases and 4 (5.3%) controls. XMRV and HCMV infections were detected in one and six control samples, respectively. The risk of PC was significantly increased (Odds Ratio = 3.98; 95% CI: 1.17-13.56, p = 0.027) by infection of the prostatic tissue with HPV. BKV, JCV, and SV40 sequences were not detected in any of the tissue samples examined.

Conclusions

We report a positive association between PC and HPV infection. The 462Q/Q RNASEL genotype was not represented in our PC cases; thus, its interaction with prostate viral infections and cancer could not be evaluated.

Human papillomavirus types 16, 18, and 31 serostatus and prostate cancer risk in the Prostate Cancer Prevention Trial

Since human papillomavirus (HPV) infection was first identified as a risk factor for cervical cancer, several seroepidemiologic and tissue-based studies have investigated HPV in relation to prostate cancer, another common genitourinary malignancy, with mixed results. To further inform this potential association, we conducted a large, prospective investigation of HPV types 16, 18, and 31 in relation to risk of prostate cancer in the Prostate Cancer Prevention Trial. Cases were a sample of men diagnosed with prostate cancer after visit 2 or on their end-of-study biopsy (n = 616). Controls were men not diagnosed with prostate cancer during the trial or on their end-of-study biopsy (n = 616). Controls were frequency matched to cases by age, treatment arm, and family history of prostate cancer. Sera from visit 2 were tested for IgG antibodies against HPV types 16, 18, and 31. No associations were observed for weak or strong HPV-16 [odds ratio (OR), 0.94; 95% confidence interval (95% CI), 0.53-1.64 and OR, 1.07; 95% CI, 077-1.48, respectively], HPV-18 (OR, 0.75; 95% CI, 0.27-2.04 and OR, 0.87; 95% CI, 0.47-1.63, respectively), or HPV-31 seropositivity (OR, 0.76; 95% CI, 0.45-1.28 and OR, 1.15; 95% CI, 0.80-1.64, respectively) and risk of prostate cancer. Considering this finding in the context of the HPV and prostate cancer literature, HPV does not appear to be associated with risk of prostate cancer, at least by mechanisms proposed to date, and using epidemiologic designs and laboratory techniques currently available.

Sexually transmissible infections and prostate cancer risk

BACKGROUND

Sexually transmissible infections (STI) have been variably associated with increased risks of prostate cancer, largely in case-control studies.

METHODS

In the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, we examined risk of prostate cancer in relation to serum antibodies to Chlamydia trachomatis, human papillomavirus-16 and -18, herpes simplex virus-2, cytomegalovirus, and human herpesvirus-8 in 868 cases (765 Whites and 103 Blacks) and 1,283 controls matched by race, age, time since initial screening, and year of blood draw; all blood samples were collected at least 1 year before prostate cancer diagnosis, except for 43 Black cases. We also assessed risk associated with self-reported history of syphilis and gonorrhea.

RESULTS

Prevalences of the 7 STIs among controls were weakly correlated, and all were more frequent among Blacks than Whites, except for human herpesvirus-8. Among Whites, prostate cancer risk was not significantly associated with the individual infections or with their number (P(trend) = 0.1); however, men with one or more STI had slightly higher risk (odds ratio, 1.3; 95% confidence interval, 1.0-1.6). Among Blacks, excess risk was associated with IgA antibody to C. trachomatis (odds ratio, 2.1; 95% confidence interval, 1.2-3.6).

CONCLUSION

This large prospective study of prostate cancer shows no consistent association with specific STIs and a borderline association with any versus none. Whether a shared response or correlated infection not directly measured underlies the weak association requires further study.