Human papilloma virus DNA and p53 mutation analysis on bladder washes in relation to clinical outcome of bladder cancer

Unveiling the Role of Human Papillomavirus in Urogenital Carcinogenesis a Comprehensive Review

Human papillomavirus (HPV), an oncogenic DNA virus, is the most common sexually transmitted virus and significant public health concern globally. Despite the substantial prevalence of HPV infection among men, routine testing remains elusive due to the lack of approved HPV tests and the complexity of detection methods. Various studies have explored the link between HPV and genitourinary cancers, revealing different associations influenced by geographic variation, histological subtype and methodological differences. These findings underscore the importance of further research to elucidate the role of HPV in male urogenital cancers. This comprehensive review delves into the intricate relationship between HPV and male genitourinary cancers, shedding light on the virus's oncogenic mechanisms and its reported prevalence. A deeper understanding of HPV's implications for male health is essential for advancing public health initiatives and reducing the burden of urogenital cancers worldwide.

Role of human papillomavirus and associated viruses in bladder cancer: An updated review

Bladder cancer (BC) is a complex disease affecting the urinary system and is regulated by several carcinogenic factors. Viral infection is one such factor that has attracted extensive attention in BC. Human papillomavirus (HPV) is the most common sexually transmitted infection, and although multiple researchers have explored the role of HPV in BC, a consensus has not yet been reached. In addition, HPV-associated viruses (e.g., human immunodeficiency virus, herpes simplex virus, BK virus, and JC virus) appear to be responsible for the occurrence and progression of BC. This study systematically reviews the relationship between HPV-associated viruses and BC to elucidate the role of these viruses in the onset and progression of BC. In addition, the study aims to provide a greater insight into the biology of HPV-associated viruses, and assess potential strategies for treating virus-induced BC. The study additionally focuses on the rapid development of oncolytic viruses that provide a potentially novel option for the treatment of BC.

Human papillomaviruses and bladder cancer risk: first report in south of Iran

Information regarding the possible carcinogenicity of human papillomaviruses (HPVs) in bladder tissue might pave the way for the prevention of bladder cancer through improving HPV vaccination of the at-risk population. To address this, this study was conducted to detect HPVs in bladder cancer tissues in the South of Iran. Bladder biopsy samples of 181 patients with bladder cancer were included in this study. The detection of HPVs was performed by nested PCR assay, targeting the L1 region of the genome, and sequencing. HPV was detected in 0.55% of the bladder cancer samples, while the non-cancerous bladder samples were negative for HPV. HPV genotype 6 was detected in this study. The HPV-positive patient was a 55-year-old man with papillary urothelial neoplasms of low malignant in stage Ta-T1. This patient was resident of Dayer city. Overall, HPV prevalence among patients with bladder cancer was not statistically associated with place of residency, gender, age, stage, and grade of the tumor (P value > 0.05). The presence of HPV is extremely rare in bladder cancer biopsy specimens in the south of Iran. Therefore, the results of our study rule out the possible role of HPVs in the etiology of bladder cancer. Due to the increasing air pollution in this region and high-risk jobs, and habits such as cigarette smoking and hookah smoking, the role of these factors alongside genetic factors seems more prominent than the role of HPVs in causing bladder cancer in the south of Iran.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13337-023-00819-w.

The association between human papillomavirus and bladder cancer: Evidence from meta-analysis and two-sample mendelian randomization

INTRODUCTION

Bladder cancer (BCa) is the 10th most common type of cancer worldwide, and human papillomavirus (HPV) is the most common sexually transmitted infection. However, the relationship between HPV infection and the risk of BCa is still controversial and inconclusive.

METHODS

This systematic review and meta-analysis were conducted following the PRISMA 2020 reporting guideline. This study searched four bibliographic databases with no language limitation. The databases included PubMed (Medline), EMBASE, Cochrane Library, and Web of Science. Studies evaluating the interaction between HPV infection and the risk of BCa from inception through May 21, 2022, were identified and used in this study. This study estimated the overall and type-specific HPV prevalence and 95% confidence intervals (95% CI) using Random Effects models and Fixed Effects models. In addition, this study also calculated the pooled odds ratio and pooled risk ratio with 95% CI to assess the effect of HPV infection on the risk and prognosis of bladder cancer. Two-sample mendelian randomization (MR) study using genetic variants associated with HPV E7 protein as instrumental variables were also conducted.

RESULTS

This study retrieved 80 articles from the four bibliographic databases. Of the total, 27 were case-control studies, and 53 were cross-sectional studies. The results showed that the prevalence of HPV was 16% (95% CI: 11%-21%) among the BCa patients, most of which were HPV-16 (5.99% [95% CI: 3.03%-9.69%]) and HPV-18 (3.68% [95% CI: 1.72%-6.16%]) subtypes. However, the study found that the prevalence varied by region, detection method, BCa histological type, and sample source. A significantly increased risk of BCa was shown for the positivity of overall HPV (odds ratio [OR], 3.35 [95% CI: 1.75-6.43]), which was also influenced by study region, detection method, histological type, and sample source. In addition, the study found that HPV infection was significantly associated with the progression of BCa (RR, 1.73 [95% CI: 1.39-2.15]). The two-sample MR analysis found that both HPV 16 and 18 E7 protein exposure increased the risk of BCa (HPV 16 E7 protein: IVW OR per unit increase in protein level = 1.0004 [95% CI: 1.0002-1.0006]; p = 0.0011; HPV 18 E7 protein: IVW OR per unit increase in protein level = 1.0003 [95% CI: 1.0001-1.0005]; p = 0.0089).

CONCLUSION

In conclusion, HPV may play a role in bladder carcinogenesis and contribute to a worse prognosis for patients with BCa. Therefore, it is necessary for people, especially men, to get vaccinated for HPV vaccination to prevent bladder cancer.

Are bladder washing samples suitable for investigation of HPV infection in urinary bladder? Comparison in HPV prevalence between urine and washing samples

Although urine and bladder washing samples are commonly used for the cytological evaluation of the bladder mucosa, it has been unknown whether these samples are likely suitable to investigate human papillomavirus (HPV) prevalence in the urinary bladder. The present study aimed to elucidate the appropriateness of spontaneously voided urine or bladder washing in screening HPV infection in the urinary bladder. Urine and bladder washing samples were obtained from 201 patients who underwent transurethral bladder tumor resection. After extracting DNA from both samples, HPV-DNA was examined using a nested polymerase chain reaction with GP5+/6+ and MY09/11 primers. HPV genotyping was performed in the HPV-positive samples. In situ hybridization (ISH) was performed to observe the HPV-DNA localization in urothelial cells among cytological samples and paraffin-embedded tumor tissues in HPV-positive washing samples. HPV prevalence in urine and washing samples were 9.5% and 7.0%, respectively. High-risk HPV prevalence in urine and washing samples was 7.5% and 4.0%, respectively. The most common HPV type was HPV 16, followed by HPV 52 and HPV 18 in both samples. HPV type distribution in both samples was not in agreement (κ = -0.431). The ISH analysis revealed that HPV-DNA signal was observed in urothelial cells of five (55.7%) of nine detectable HPV-positive cytological samples. Six (66.7%) of nine HPV-positive cases had HPV-DNA signals in tumor tissue. The use of washing samples was likely applicable for investigating HPV prevalence in the urinary bladder. HPV-DNA detected in washing samples might be frequently derived from the urinary bladder.

Systematic review on oncologic outcomes on adjuvant endovesical treatment for non-muscle invasive bladder cancer in patients with solid organ transplant

PURPOSE

Urothelial carcinoma has a higher incidence in renal transplanted patients according to several registries (relative risk × 3), and the global prognosis is inferior to the general population. The potential impact of immunosuppressive therapy on the feasibility, efficacy, and complications of endovesical treatment, especially Bacillus Calmette-Guerin, has a low level of evidence. We performed a systematic review that aimed to assess the morbidity and oncological outcomes of adjuvant endovesical treatment in solid organ transplanted patients.

METHODS

Medline was searched up to December 2021 for all relevant publications reporting oncologic outcomes of endovesical treatment in solid organ transplanted patients with NMIBC. Data were synthesized in light of methodological and clinical heterogeneity.

RESULTS

Twenty-three retrospective studies enrolling 238 patients were included: 206 (96%) kidney transplants, 5 (2%) liver transplants, and 2 (1%) heart transplants. Concerning staging: 25% were pTa, 62% were pT1, and 22% were CIS. 140/238 (59%) patients did not receive adjuvant treatment, 50/238 (21%) received mitomycin C, 4/238 (2%) received epirubicin, and 46/238 (19%) received BCG. Disease-free survival reached 35% with TURBT only vs. 47% with endovesical treatment (Chi-square test p = 0.08 OR 1.2 [0.98-1.53]). The complication rate of endovesical treatment was 12% and was all minor (Clavien-Dindo I).

CONCLUSION

In solid organ transplanted patients under immunosuppressive treatment, both endovesical chemotherapy and BCG are safe, but the level of evidence concerning efficacy in comparison with the general population is low. According to these results, adjuvant treatment should be proposed for NMIC in transplanted patients as in the general population.

Detection of HPV infection in urothelial carcinoma using RNAscope: Clinicopathological characterization

Background

Human papillomavirus (HPV) is a well‐established mucosotropic carcinogen, but its impact on urothelial neoplasm is unclear. We aimed to clarify the clinical and pathological features of HPV‐related urothelial carcinoma (UC).

Methods

Tissue samples of 228 cases of UC were obtained from the bladder, upper and lower urinary tract, and metastatic sites to construct a tissue microarray. The samples were analyzed for the presence of HPV by a highly sensitive and specific mRNA in situ hybridization (RISH) technique (RNAscope) with a probe that can detect 18 varieties of high‐risk HPV. We also conducted immunohistochemistry (IHC) for a major HPV capsid antibody and DNA‐PCR.

Results

The HPV detection rates varied among the methods; probably due to low HPV copy numbers in UC tissues and the insufficient specificity and sensitivity of the IHC and PCR assays. The RISH method had the highest accuracy and identified HPV infection in 12 (5.2%) of the cases. The histopathological analysis of the HPV‐positive UC showed six cases of usual type UC, five cases of UC with squamous differentiation (UC_SqD), and one case of micropapillary UC. The HPV detection rate was six‐fold higher in the cases of UC_SqD than in the other variants of UC (odds ratio [OR] =8.9, p = 0.002). In addition, HPV infection showed a significant association with tumor grade (OR =9.8, p = 0.03) and stage (OR =4.7, p = 0.03) of UC. Moreover, the metastatic rate was higher in HPV‐positive than in negative UC (OR =3.4).

Conclusion

These data indicate that although the incidence of HPV infection in UC is low, it is significantly associated with squamous differentiation and poor prognosis. Furthermore, our observations show that RNAscope is an ideal method for HPV detection in UC compared with the other standard approaches such as IHC and PCR assays.

Expression and prognostic value of SULT1A2 in bladder cancer

Sulfotransferase Family 1A Member 2 (SULT1A2) is a protein coding gene. Several studies have reported that SULT1A2 may have a chemical carcinogenic effect if expressed as a functional protein. The present study aimed to investigate the expression and potential role of SULT1A2 in bladder cancer (BC). Data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus databases were used to analyze SULT1A2 expression in BC. In addition, reverse transcription-quantitative PCR and western blot analyses were performed to detect SULT1A2 expression in BC cells and tissues. Immunohistochemistry analysis was performed on 100 formalin-fixed, paraffin-embedded BC tissues and corresponding adjacent normal bladder tissues (ANBTs) to verify SULT1A2 expression and determine the clinical significance of SULT1A2 in BC. Gene set enrichment analysis (GSEA) was performed to determine the potential biological processes and internal molecular mechanisms. The results demonstrated that SULT1A2 was highly expressed in BC tissues compared with ANBTs. Furthermore, high SULT1A2 expression was significantly associated with the staging of BC. Analyses of TCGA datasets and BC tissue microarray indicated that high SULT1A2 expression was significantly associated with a favorable overall survival in patients with BC. In addition, GSEA revealed pathways, diseases and biological processes associated with SULT1A2. Taken together, the results of the present study suggest that SULT1A2 acts as an oncogene in BC, and thus may serve as a biomarker for tumor staging and prognosis in patients with BC.

Management of de-novo urothelial carcinoma in transplanted patients

PURPOSE OF REVIEW

The aim of this article is to review incidence, risk factors, and optimal management of de-novo urothelial carcinoma in transplant recipients.

RECENT FINDINGS

There is a two to three-fold increased risk for de-novo malignant tumors after solid-organ transplantation, but there is currently no consensus regarding optimal management of de-novo urothelial carcinoma in transplanted patients. Known risk factors include polyomavirus BK, aristolochic acid, and smoking. Data suggest a higher rate of high-grade tumors, as well as predominantly higher stage at primary diagnosis, for both NMIBC and muscle-invasive bladder cancer (MIBC). Treatment for NMIBC includes TURB, mitomycin, and Bacille de Calmette-Guérin instillation with special concern to the immunosuppressive regime. Treatment of MIBC or advanced urothelial carcinoma includes radical cystectomy with chemotherapy if the patient is eligible. A screening should be performed in all transplant recipients, to allow early diagnosis.

SUMMARY

De-novo urothelial carcinoma in transplant recipients is more frequent than in the general population and these tumors were more likely to be high-grade tumors and diagnosed at an advanced stage. There is very little information available on the optimal treatment for these patients. However, aggressive treatment and a strict management according the given recommendations are of the utmost importance.

Human Papillomavirus, MicroRNA and their Role in Cervical Cancer Progression, Diagnosis and Treatment Response: A Comprehensive Review

Human Papillomavirus (HPV) is sexually transmitted and linked with vaginal, vulvar and cervix cancers in females, penile cancer in male, while anal and oropharyngeal cancer in both genders. Cervical cancer is ranked as third most identified cancer among females globally and is the fourth leading reason of cancer related mortality. The main aim of current study is to highlight the key role of miRNA in cervical cancer development, progression and their therapeutic responses. Current study entailed more than 50 PubMed cited articles related to miRNA role in cervical cancer. Studies have elucidated the role of miRNAs regulation in gene expression at post-transcriptional and translational level by targeting significant genes and therefore involved in cervical cancer. miRNAs control several cellular pathways involved in development of pre-malignant to metastatic stage and proliferation to malignancy. Current review elucidated and elaborated the key role of miRNA their application, treatment and therapeutic responses in cervical cancer.

Human papilloma virus and genitourinary cancers: a narrative review

INTRODUCTION

Human papilloma virus (HPV) is the most common sexually transmitted pathogen and its potential role in the genesis of several diseases such as cervical, head and neck, anal and penile cancers, is now largely recognized. Aim of this review article was to evaluate and summarize the state of the art of HPV-related urogenital cancers, focusing on the potentially innovative methods for the diagnosis of infection that should be used to improve viral causative detection and prevent its diffusion through sexual intercourses.

EVIDENCE ACQUISITION

The initial search was carried out by using the Medline and the Google Scholar computerized databases through the selected key-words to identify the more recent literature on HPV epidemiology and its relationship with the main relevant urinary tract cancers. Studies were selected, extracted, analyzed and summarized. The PRISMA statement criteria were adopted and reported.

EVIDENCE SYNTHESIS

Polymerase chain reaction assay (HPV test) represents the best option for the diagnosis of HPV infection. Difficulties for the diagnosis in male are due to the site of investigation (glans, sub coronal sulcus, scrotum, urine, sperm) and the method adopted to take the sample (brushing, tissue biopsy). Due to these reasons several studies analyzed seemed to be incomparable. HPV infection is generally found in about 20% of heterosexual men. Its connection with cervical, anal, head and neck and penile cancer has been previously evidenced in 90%, 60%, 68% and 40% of cases respectively. In particular, HPV infection differed significantly among penile squamous cell carcinoma (SCC) subtypes ranging from 22.4% in verrucous subtype to 66.3% for the basaloid/warty subtype. Although the connection between prostate cancer and HPV infection has never been previously confirmed, forest plot analysis relative to a series of nine studies done during the last ten years, demonstrated a 7.7 objective risk (OR) for subjects with HPV infection to develop subsequent prostate cancer. On the other hand, some authors found comparable results in subjects with prostate cancer, benign prostate hyperplasia and prostate inflammation, thus demonstrating that this link still remains questionable. Similarly, the connection between HPV infection and urothelial, testicular and renal cancer continue to be hotly debated although HPV has been found in the urine, semen and renal tissue of patients respectively.

CONCLUSIONS

Integrated parts of HPV (E6 and E7 fractions) have been previously found in cervical, head and neck, anal and penile cancers. Conversely, although the evidence of concomitant HPV infection, integrated viral genome in cancer cells DNA had never been demonstrated in all the other genito-urinary tract cancers, and its role in the tumor genesis remain still largely debated. This is the reason why HPV infection should be tested in all patients with genitourinary cancer to better investigate about its potential role in the tumor genesis and development. Moreover, HPV infection option should be kept in mind when considering possible viral transmission to sexual partners.

Risk factors for human papillomavirus detection in urine samples of heterosexual men visiting urological clinics in Japan

OBJECTIVE

The present study aimed to investigate human papillomavirus (HPV) prevalence and identify risk factors for HPV detection in urine samples among heterosexual men attending urological clinics.

MATERIALS AND METHODS

Spot urine samples including initial stream were collected from 845 participants, and the cell pellets were preserved into liquid-based cytological solution. After DNA extraction from each sample, HPV-DNA amplification and genotyping were performed using Luminex multiplex polymerase chain reaction. Participants completed a questionnaire on their age, education, smoking status, sexuality, age of sexual debut, marital status, and present history of sexually transmitted infections.

RESULTS

Data from 803 patients were included in the analysis. Overall HPV and high-risk (HR)HPV prevalence in urine samples were 6.2% and 3.1%, respectively. HPV and HR-HPV prevalences were the highest in men with urethritis, and were significantly higher than those without urethritis. HPV detection was the most common in men aged 40-49 years, although significant detection differences were not age-related. Urethritis was an independent risk factor for HPV detection from urine samples, with an odds ratio (OR) of 4.548 (95%CI; 1.802-11.476) (p = 0.001). On the other hand, a sub-analysis excluding men with urethritis demonstrated that prostate cancer was a significant risk factor for HPV detection, with OR of 2.844 (95%CI; 1.046-7.732) (p = 0.0410), whereas was not a significant risk for HR-HPV detection in urine samples.

CONCLUSION

Prostate cancer may represent a risk factor for HPV detection in the urine of men without urethritis.

REGISTRATION OF CLINICAL TRIALS

The authors did not register to Clinical Trial because this is observational and cross-sectional study.

A clinical and molecular review of inverted papilloma of the urinary tract: how to handle?

Inverted papilloma (IP) of the urinary tract is classified by the World Health Organisation as a non-invasive urothelial tumour with normal to minimal cytological atypia of the neoplastic cells. During the 1980s, it came under suspicion of having a premalignant or malignant potential and of being concurrent with urothelial cell carcinoma (UCC). This quandary has been proven difficult to solve, due to the fact that IP is very rare and literature mostly consists of case reports with varying levels of information, making strong meta-analyses problematic. New immunohistochemical techniques and genetic approaches are more frequently being used in the attempt to achieve better classifications, prognosis and treatment of lesions hereunder IP. This review will, in our awareness, be the first to combine the knowledge from retrospective studies with these new approaches for determining a possible premalignant potential and concurrency with UCC and subsequently outline a recommendation for follow-up.

Human papillomavirus infection and pathogenesis in urothelial cells: a mini-review

Several recent studies described that high-risk human papillomavirus (HPV) infection could have a potential role in the development of malignancies other than cervical cancer, such as laryngeal carcinoma, penile carcinoma, and anal carcinoma. However, the etiological role of HPV infection in the pathogenesis of urinary tract has not been clarified. Many epidemiological studies demonstrated that HPV infections frequently occur in the external genitalia through sexual contact; however, it was reported that HPV infection could also occur in the urinary tract, including the urethra and urinary bladder. Some morphological changes of cells associated with HPV infection and mild atypical cells, suspected to be intraneoplasia, were seen in HPV-positive samples obtained from the urinary tract. Some clinical studies and meta-analysis have indicated that HPV infection is likely to have a certain etiological correlation with the development of bladder carcinoma, although its prevalence may vary according to HPV type, study population, region, histological type, detection methods, and other variables. According to the results of previous studies, the prevalence of HPV greatly widely varies in cases of bladder carcinoma. Further research by case-control or large-scales studies is thus required to reach a more definite conclusion.

Joint infectious causation of human cancers

Joint infectious causation of cancer has been accepted in a few well-studied instances, including Burkitt's lymphoma and liver cancer. In general, evidence for the involvement of parasitic agents in oncogenesis has expanded, and recent advances in the application of molecular techniques have revealed specific mechanisms by which host cells are transformed. Many parasites evolve to circumvent immune-mediated detection and destruction and to control critical aspects of host cell reproduction and survival: cell proliferation, apoptosis, adhesion, and immortalization. The host has evolved tight regulation of these cellular processes-the control of each represents a barrier to cancer. These barriers need to be compromised for oncogenesis to occur. The abrogation of a barrier is therefore referred to as an essential cause of cancer. Alternatively, some aspects of cellular regulation restrain but do not block oncogenesis. Relaxation of a restraint is therefore referred to as an exacerbating cause of cancer. In this chapter, we explore past and current evidence for joint infectious causation of cancer in the context of essential and exacerbating causes. We stress that discovery of joint infectious causation may provide great improvements in controlling cancer, particularly through the identification of many additional nonhuman targets for synergistic interventions for prevention and treatment.

Detection of human papillomavirus infection and p16 immunohistochemistry expression in bladder cancer with squamous differentiation

OBJECTIVES

To determine the potential association between HPV infection and the squamous cell component of urothelial carcinoma (UC) of the bladder and to validate p16 overexpression as a surrogate marker for HPV infection in these cancers among Koreans.

METHODS

We analyzed the presence of HPV infection using an HPV-DNA chip and the expression of p16 using immunohistochemistry in 47 subjects between July 2001 and March 2011. The study group (n = 35) included patients with squamous differentiation of UC of the bladder. The control group (n = 12) included patients with squamous metaplasia of the bladder.

RESULTS

Baseline characteristics of control and study groups were similar. HPV DNA detection rates were approximately 2-fold higher in the study than the control group (17.1% [6/35] versus 8.3% [1/12], respectively), but the difference was not statistically significant. P16 overexpression was detected in 16/35 (45.7%) study group and 1/12 (8.3%) control group samples (p = 0.034). Both HPV-positivity and p16 overexpression were present in 3/35 (8.8%) study group samples, but none of the control group (p = 0.295). In the study group, the percentage of HPV-positive cases who were non-smokers was 2-fold higher than the percentage of HPV-negative cases who were non-smokers (66.7% [4/6] versus 31.0% [9/29], respectively); however, statistical significance was not achieved due to the small sample size.

CONCLUSIONS

HPV infection may be associated with UC of the bladder with squamous differentiation, especially in non-smokers. However, p16 expression does not appear to be a strong surrogate marker for evidence of HPV infection in this type of cancer.

Etiological correlation of human papillomavirus infection in the development of female bladder tumor

The critical factors and etiological role of human papillomavirus (HPV) infection in the development of female bladder tumor were examined. Eighty-four female patients with primary bladder tumor were studied. After DNA extraction from each paraffin-embedded tissue, HPV-DNA and genotype were checked. In cases of all HPV-positive cases and some HPV-negative cases, in situ hybridization (ISH) for high-risk HPV-DNA, and immunohistochemical analysis for p16-INK4a were performed. HPV-DNA was detected in 5 (6.0%) of 84 eligible patients, and HPV16 was detected in 3 patients, and HPV6 and HPV52 was detected in one case, respectively. HPV-DNA was detected frequently in younger patients and in patients with a history of cervical cancer. In four high-risk HPV-positive cases, high-risk HPV-DNA was present in tumor tissues, and p16-INK4a was expressed moderately or strongly. Two cases had a past history of cervical cancer. In these 2 cases, the same HPV type (HPV16) was detected from bladder tumor and cervical cancer. High-risk HPV-DNA ISH signals and p16-INK4A expression were also detected widely in these cervical cancer tissues. HPV infection is likely to play an important role in the development of female bladder tumor at younger cases with a past history of cervical cancer.

p16 expression is not associated with human papillomavirus in urinary bladder squamous cell carcinoma

Squamous cell carcinoma of the urinary bladder is unusual and of unknown etiology. There is a well-established association between human papillomavirus (HPV) infection and the development of cervical and head/neck squamous cell carcinomas. However, the role of HPV in the pathogenesis of squamous cell carcinoma of the urinary bladder is uncertain. The purposes of this study were to investigate the possible role of HPV in the development of squamous cell carcinoma of the urinary bladder and to determine if p16 expression could serve as a surrogate marker for HPV in this malignancy. In all, 42 cases of squamous cell carcinoma of the urinary bladder and 27 cases of urothelial carcinoma with squamous differentiation were investigated. HPV infection was analyzed by both in situ hybridization at the DNA level and immunohistochemistry at the protein level. p16 protein expression was analyzed by immunohistochemistry. HPV DNA and protein were not detected in 42 cases of squamous cell carcinoma (0%, 0/42) or 27 cases of urothelial carcinoma with squamous differentiation (0%, 0/15). p16 expression was detected in 13 cases (31%, 13/42) of squamous cell carcinoma and 9 cases (33%, 9/27) of urothelial carcinoma with squamous differentiation. There was no correlation between p16 expression and the presence of HPV infection in squamous cell carcinoma of the bladder or urothelial carcinoma with squamous differentiation. Our data suggest that HPV does not play a role in the development of squamous cell carcinoma of the urinary bladder or urothelial carcinoma with squamous differentiation. p16 expression should not be used as a surrogate marker for evidence of HVP infection in either squamous cell carcinoma of the urinary bladder or urothelial carcinoma with squamous differentiation as neither HVP DNA nor protein is detectable in these neoplasms.

Association of human herpes, papilloma and polyoma virus families with bladder cancer

The aim of the present study was to assess the possible etiologic role of human papillomavirus (HPV), human herpes virus (HHV) and the human polyoma virus families (BKV and JCV) in the tumourigenesis of bladder cancer. Thirty biopsy specimens from patients with different grades and stages of bladder cancer, who underwent transurethral bladder cancer resection, and 30 normal bladder mucosa specimens were analysed using polymerase chain reaction (PCR) for the detection of the above three virus family members. The presence of HPV was determined in all specimens with nested PCR and real-time quantitative PCR. All cancerous specimens, including the control group, were found to be negative both by PCR and real-time qPCR for the presence of HPV DNA, whilst all samples examined by PCR tested negative for the presence of HSV-1,2 Varicella zoster virus and HSV-7 DNA. Cytomegalovirus, HHV-6 and HHV-8 exhibited similar incidence in sample positivity in both cancerous and healthy tissues. EBV showed a higher prevalence in bladder cancer specimens compared to healthy tissue (p = 0.048), whilst BKV and JCV were detected only in tumour samples. The presence of EBV in a significant proportion of bladder tumours indicates the etiological role of this virus in cancer tumourigenesis.

Meta-analysis of studies analyzing the role of human papillomavirus in the development of bladder carcinoma

PURPOSE

We aimed to ascertain the degree of association between bladder cancer and human papillomavirus (HPV) infection.

MATERIALS AND METHODS

We performed a meta-analysis of observational studies with cases and controls with publication dates up to January 2011. The PubMed electronic database was searched by using the key words "bladder cancer and virus." Twenty-one articles were selected that met the required methodological criteria. We implemented an internal quality control system to verify the selected search method. We analyzed the pooled effect of all the studies and also analyzed the techniques used as follows: 1) studies with DNA-based techniques, among which we found studies with polymerase chain reaction (PCR)-based techniques and 2) studies with non-PCR-based techniques, and studies with non-DNA-based techniques.

RESULTS

Taking into account the 21 studies that were included in the meta-analysis, we obtained a heterogeneity chi-squared value of Q(exp)=26.45 (p=0.383). The pooled odds ratio (OR) was 2.13 (95% confidence interval [CI], 1.54 to 2.95), which points to a significant effect between HPV and bladder cancer. Twenty studies assessed the presence of DNA. The overall effect showed a significant relationship between virus presence and bladder cancer, with a pooled OR of 2.19 (95% CI, 1.40 to 3.43). Of the other six studies, four examined the virus's capsid antigen and two detected antibodies in serum by Western blot. The estimated pooled OR in this group was 2.11 (95% CI, 1.27 to 3.51), which confirmed the relationship between the presence of virus and cancer.

CONCLUSIONS

The pooled OR value showed a moderate relationship between viral infection and bladder tumors.

Etiological role of human papillomavirus infection for inverted papilloma of the bladder

The status of human papillomavirus (HPV) infection in urothelial inverted papilloma was examined in the present study. Formalin-fixed and paraffin-embedded tissues from eight cases of inverted papilloma of the bladder were studied. The presence of HPV-DNA was examined by modified GP5/6+PCR using archival tissue sections by microdissection. HPV genotype was determined with a Hybri-Max HPV genotyping kit. Immunohistochemical analysis for p16-INK4a, mcm7, HPV-E4, and L1, and in situ hybridization for the HPV genome were performed. HPV was detected in seven of eight cases (87.5%) of inverted papilloma. Three cases were diagnosed as inverted papilloma with atypia, while the remaining five were typical cases. HPV-18 was detected in two cases, including one inverted papilloma with atypia, and HPV-16 was detected in four cases, including one inverted papilloma with atypia. Multiple HPV type infection was detected in one typical case and one atypical case. High-risk HPV was present in all HPV-positive cases. Cellular proteins, p16-INK4a and mcm7, which are surrogate markers for HPV-E7 expression, were detected in all HPV-positive cases, and their levels were higher in inverted papilloma with atypia than in typical cases. In contrast, HPV-E4 and L1, which are markers for HPV propagation, were observed in some parts of the typical inverted papilloma tissue. High-risk HPV infection may be one of the causes of urothelial inverted papilloma, and inverted papilloma with atypia may have malignant potential.

Etiologic role of human papillomavirus infection in bladder carcinoma

BACKGROUND

The authors elucidated an etiologic role of human papillomavirus (HPV) infection in carcinoma of the bladder.

METHODS

One hundred seventeen of 224 patients with bladder carcinoma who were treated between 1997 and 2009 were enrolled in this study. The presence of HPV DNA was tested on frozen carcinoma tissues that were obtained by transurethral resection using a polymerases chain reaction-based method. Localization of HPV was observed on archival tissue specimens by in situ hybridization (ISH) for high-risk HPV DNA. Cyclin-dependent kinase (CDK) inhibitor 2A (inhibits CDK4) (p16-INK4a) and minichromosome maintenance protein-7 (mcm-7)-surrogate markers for high-risk HPV-E7 oncoprotein-and HPV-L1 (capsid) protein expression were evaluated by immunohistochemistry.

RESULTS

HPV types 16, 18, 31, 33, 52, and 58, and an unknown HPV type were detected in 18 of 117 samples (15%) from patients with bladder carcinoma. HPV16 was identified in 6 samples, HPV18 was identified in 4 samples, and HPV33 was identified in 3 samples. All were single HPV type infections. HPV was detected in 38% (12 of 28) of histologic grade 1 bladder carcinomas, 8.5% (6 of 71) of grade 2 bladder carcinomas, and in 0% (0 of 18) of grade 3 bladder carcinomas. Multivariate analysis indicated that younger age (<60 years; odds ratio [OR], 10.9; 95% confidence interval [CI], 2.6-45.3) and grade 1 tumors (OR, 4.5; 95% CI, 1.2-17.0) were associated with HPV infection. ISH analysis indicated that high-risk HPV DNA was localized in the nuclei of tumor cells of all HPV-positive samples. p16-INK4a and mcm-7 were expressed in 94% and 89% of HPV-positive carcinoma cells, respectively. HPV-L1 protein expression, which suggested reproductive HPV infection, was not observed in any carcinoma.

CONCLUSIONS

The current results indicated that high-risk HPV is likely to be a causative agent of some low-grade bladder carcinomas that develop in younger patients.

99th Dahlem conference on infection, inflammation and chronic inflammatory disorders: symbionts and immunopathology in chronic diseases: insights from evolution

Immunological aetiologies of disease are not generally well understood, but have been attributed to intrinsic immunological imbalances, infectious triggers or persistent infections. Evolutionary considerations lead to the formulation of three feasible categories of immunopathology for common diseases. One category of hypotheses presumes that the immune system is exposed to environmental conditions to which the individual is not well adapted. One hypothesis within this category, often referred to as the hygiene hypothesis, proposes that new more hygienic environmental conditions have generated compositions of symbionts that differ from those to which humans have been adapted. A second category of hypotheses proposes that infectious agents act as triggers of immunopathology by shifting the immune system into a self-destructive state. A third category proposes that infectious agents keep the immune in a self-destructive state by causing persistent infections. To evaluate disease causation rigorously and to determine the appropriate interventions, these three categories of causation need to considered for every disease that involves immunopathology. Assessment of the progress in understanding oncogenesis and other chronic diseases emphasizes the value of such integrated assessments.

Infection: is it a cause of bladder cancer?

This article reviews the literature regarding the possible correlation between infection and occurrence of bladder cancer. The PubMed literature database was searched from inception to January 2008. Keywords of bladder, cancer, parasitic, bacterial, viral and infection, were used. Forty studies were included in the review. Several investigators support the idea that schistosomiasis is aetiologically related to the development of bladder cancer in individuals infected with Schistosoma haematobium. Approximately 70% of those with chronic schistosomiasis who have bladder cancer develop squamous cell rather than transitional cell carcinoma. Several investigators suggest that bacteria may play a role in inducing bladder cancer. Clinically, researchers have linked the development of infection, urinary stones and indwelling catheters with bladder cancer. Nevertheless, to date, no prospective study has examined the association between urinary tract infection and bladder cancer risk. The possibility that infection by human papilloma virus (HPV) is a risk factor contributing to bladder cancer has been investigated but no definite conclusions have been drawn. Thus, the debate remains open as to whether there is any direct link between chronic HPV infection and bladder cancer. Only 15 cases of vesical carcinoma have been reported, to date, in the setting of human immunodeficiency virus (HIV). The rare occurrence of bladder cancer during HIV infection and the lack of correlation with the laboratory markers of HIV disease progression may suggest a trivial association between two unrelated disorders. BK virus is oncogenic in newborn hamsters and can transfer to mammalian cells in vitro, but there is little consistent evidence of a link with human bladder cancer. Studies showed no correlation between herpes simplex virus (HSV) and bladder cancer, but bladder cancer becomes infected with HSV much more easily than non-neoplastic urothelium. In conclusion, with the exception of chronic infection with S. haematobium, the association between the occurrence of bladder cancer and chronic bacterial or viral infections could not be confirmed. Prospective studies with large numbers of patients and controls are required to confirm this issue.

An evolutionary perspective on parasitism as a cause of cancer

For the past half-century, the dominant paradigm of oncogenesis has been mutational changes that disregulate cellular control of proliferation. Parasitic causes of cancer were first incorporated into this paradigm by suggesting mechanisms through which parasitism might increase mutational damage, such as generation of mutagenic compounds during immunological activity. The growing recognition of the molecular mechanisms of pathogen-induced oncogenesis and the difficulty of generating oncogenic mutations without first having large populations of dysregulated cells, however, suggests that pathogens, particularly viruses, are major initiators of oncogenesis for many if not most cancers, and that the traditional mutation-driven process becomes the dominant process after this initiation. Molecular phylogenies of individual cancers should facilitate testing of this idea and the identification of causal pathogens.

Hypothesis--ultraviolet-B irradiance and vitamin D reduce the risk of viral infections and thus their sequelae, including autoimmune diseases and some cancers

Many viral infections reach clinical significance in winter, when it is cold, relative humidity is lowest and vitamin D production from solar ultraviolet-B irradiation is at its nadir. Several autoimmune diseases, such as multiple sclerosis, type 1 diabetes mellitus and asthma, are linked to viral infections. Vitamin D, through induction of cathelicidin, which effectively combats both bacterial and viral infections, may reduce the risk of several autoimmune diseases and cancers by reducing the development of viral infections. Some types of cancer are also linked to viral infections. The cancers with seemingly important risk from viral infections important in winter, based on correlations with increasing latitude in the United States, an index of wintertime solar ultraviolet-B dose and vitamin D, are bladder, prostate, testicular and thyroid cancer, Hodgkin's and non-Hodgkin's lymphoma, and, perhaps, gastric cancer. The evidence examined includes the role of viruses in the etiology of these diseases, the geographic and seasonal variation of these diseases, and the time of life when vitamin D is effective in reducing the risk of disease. In general, the evidence supports the hypothesis. However, further work is required to evaluate this hypothesis.