Sensitive detection of human papillomavirus in cervical, head/neck, and schistosomiasis-associated bladder malignancies

We assayed for the presence of human papilloma virus (HPV) DNA in serum and/or peripheral blood fraction (PBF) of individuals with cervical, head/neck, or bladder cancer due to schistosomiasis. Using mass spectroscopy coupled with competitive PCR, HPV DNA was detected at the individual molecule level by using "MassARRAY" assays. The resultant sensitivity was superior to real-time fluorescent PCR-based assays, while specificity was maintained. Our principal findings were: (i) Virtually all tested cervical cancers and schistosomiasis-associated bladder cancers, and a plurality of head/neck cancers, are associated with HPV DNA in the tumor. (ii) All 27 bladder cancers due to schistosomiasis were associated with the presence of HPV-16 DNA, which can be detected in tumor and serum but not in PBF. In contrast, no serum HPV-16 DNA signal was detected in seven individuals with schistosomiasis-associated bladder cancers after surgical removal of the tumor. (iii) Among the head/neck cancers we studied, anterior tumors were more often associated with HPV DNA in tumor, serum, and/or PBF than posterior tumors. (iv) In cervical cancer, where all tumors contain HPV DNA, viral DNA could be detected often in serum and/or PBF. Further, HPV-16 DNA was detected in serum and/or PBF of most patients with untreated high-grade cervical dysplasia but disappeared if the dysplasia was eliminated. The sensitive, specific, and quantitative MassARRAY technique should make it feasible to monitor cancer occurrence and treatment and recurrence of malignancies and dysplasias associated with HPV DNA.

SV40 Enhances the Risk of Malignant Mesothelioma among People Exposed to Asbestos: A Molecular Epidemiologic Case-Control Study

We conducted a case-control study on asbestos exposure and presence of SV40 in tumor samples of malignant mesotheliomas (MMs) and bladder urotheliomas (BUs). PCR analysis revealed the presence of SV40 DNA (SV40+) in eight (42.1%) MMs and 6 (33.3%) BUs. The odds ratio for MM Asb- and SV40+ was 0.4 [95% confidence interval (95% CI), 0.03-4.0], for Asb+ and SV40- was 3.6 (95% CI, 0.6-21.0), and for Asb+ and SV40+ was 12.6 (95% CI, 1.2-133.9). Our results suggest that SV40 increases the risk of MM among individuals exposed to asbestos.

Urinary bladder carcinoma and human papilloma virus infection, an appraisal of risk

Human papilloma virus (HPV) is a well known risk factor for cancer development in different body sites, involved in the pathogenesis of several intraepithelial lesions and cancers, for example of the upper alimenatry and respiratory tracts and cervix. Urinary bladder carcinoma is a common urological malignancy for which a relationship with human HPV has been indicated, but the results are controversial. Here, the author performed an appraisal of the previous reports on the studies to document correlation between HPV infection, defined as DNA positive, and urinary bladder carcinoma. According to the literature review, 5 reports were recruited for metanalysis, including 239 cases and 52 healthy subjects. The overall HPV DNA positive rates for the patients and healthy control subjects were 25.5 % (61/239) and 11.5 % (6/52), respectively, the odds ratio of 2.6 pointing to potential as a risk factor.

HPV 16/18-associated condyloma acuminatum of the urinary bladder: first international report and review of literature

Condyloma acuminatum is an anogenital lesion caused by human papillomavirus (HPV) infection, a common sexually transmitted disease. It usually affects the external genitalia while urethral and/or bladder involvement is rare. HPV types are classified into three categories depending on their oncogenic potential: low risk (type 6, 11, 42, 43, 44, 59, 66, 68, 70), intermediate risk (type 30, 31, 33, 34, 35, 39, 40, 49, 51, 52, 53, 57, 58, 63, 64) and high risk (type 16, 18, 45, 56). High-risk and intermediate-risk HPV-DNA types, together with other co-factors still to be defined, are responsible for over 90% of the cases of anogenital pre-malignant and malignant tumours. We report a unique case of a urinary bladder condyloma acuminatum positive for HPV 16/18 DNA, presented as the primary and only site of the disease in an immunocompetent patient. We review the treatment and follow-up strategies of this rare lesion.

Does human papillomavirus play a role in the development of bladder transitional cell carcinoma? A comparison of PCR and immunohistochemical analysis

AIM

To investigate the role of human papillomavirus (HPV) in the development of bladder transitional cell carcinoma (TCC).

METHODS

Seventy eight paraffin wax embedded TCC samples were tested for the presence of HPV by two methods. First, immunohistochemistry was carried out using a polyclonal antibody capable of detecting the capsid protein of all known papillomaviruses. The second method was a consensus GP5+/6+ primer mediated polymerase chain reaction (PCR) technique, with the products analysed by both agarose gel electrophoresis and an enzyme immunoassay using type specific oligonucleotide probes for 10 different mucosal genotypes. To exclude false negative results because of the poor quality of DNA extracted from paraffin wax embedded samples, the series was extended to include 20 further blocks for which the corresponding snap frozen unfixed tissue was available.

RESULTS

The two methods produced contrasting results, with 47 of the 78 samples positive for HPV antigen and none positive for HPV DNA. HPV DNA was not detected in the 20 additional paraffin wax embedded TCCs or in the 20 paired unfixed samples. In contrast, HPV DNA was amplified by PCR from all six of the paraffin wax embedded cervical carcinoma and anogenital wart control samples.

CONCLUSION

The disparity between the two sets of results is probably caused by false positives resulting from the non-specificity of the polyclonal antibody used for immunohistochemistry. These results suggest that HPV is unlikely to play an aetiological role in the development of bladder TCC.

Association of human herpesvirus type 6 DNA with human bladder cancer

We examined the presence of human herpesvirus type 6 (HHV6) DNA in a series of 74 bladder carcinomas from a Mediterranean population to elucidate their possible role as cofactor in the development of bladder cancer with or without associated human papillomavirus (HPV) infection. HHV-6 type B DNA was present in 5 men (6.8%) out of the 74 tumors investigated; two of them had associated HPV-16 DNA in the same specimen. In one case that had associated urothelial carcinoma in situ, both HHV-6B and HPV-16 DNA were present. In conclusion, the low incidence of HHV-6B in bladder cancer and the ubiquitous nature of HHV-6 infection are more consistent with a bystander role rather than cofactor in the oncogenesis of bladder cancer.

[Establishment of immortalized cell line BLTR-4 and primary identification of its biological character]

OBJECTIVE

To establish immortalized cell line from the urothelium of the urinary bladder and identify the characteristics of the cell line.

METHODS

Human papillomavirus 16 (HPV-16) plasmid was used to transfect urothelium of infant urinary bladder in vitro with the help of Fugene-6, and this plasmid contained E6 and E7 genes of HPV-16. We also identified the existence of HPV-16 E6 and E7 genes and the biological characteristics of the cell line by PCR, immunohistochemistry, and the biology identification.

RESULTS

BLTR-4 cell line, produced from the transfection of HPV-16K plasmid, was a cell line from urothelium with the expression of HPV-16 E6 and E7 genes. It had been cultured more than 70 passages, and the characteristics of growth was similar to the immortalized cell line as reported.

CONCLUSIONS

BLTR-4 cell line is an immortalized cell line from urothelium of the urinary bladder, which contains HPV-16 E6 and E7 genes. BLTR-4 cell line is a good experimental model to investigate the relationship of the infection of high risk HPV and transitional cell carcinoma (TCC) in vitro.

Non-viral tumor necrosis factor-alpha gene transfer decreases the incidence of orthotopic bladder tumors

Our aim was to evaluate the feasibility and efficacy of tumor necrosis factor-alpha gene therapy in preventing bladder tumor recurrence using an orthotopic model of bladder cancer. We transiently transfected a murine bladder cancer cell line MB49 with pBud-TNF-alpha using a transfection system consisting of the cationic liposome N-(1-(2,3-dioleoyloxyl)propyl)-N,N,N-trimethylammoniummethyl sulfate (DOTAP) plus methyl-beta-cyclodextrin solubilized cholesterol (MBC). MB49 cells produced 893.7+/-24.0 pg/ml of TNF-alpha 2 days after transfection. Cell growth was inhibited, apoptosis was induced and MHC class I, B7.1 and Fas expression on the MB49 cells were increased. In vivo, an orthotopic murine bladder cancer model was established by intravesical instillation of bladder cancer cells after transurethral cauterization of the mouse bladder mucosa. TNF-alpha gene transfer was initiated 2 days after the tumor inoculation, when the tumor burden was small, and given twice per week for 3 weeks. RT-PCR showed TNF-alpha mRNA was observed to increase after the first instillation and then return to basal level 1 month after the sixth instillation. Histology revealed that TNF-alpha gene transfer decreases the bladder tumor incidence from 75% for the control group to 25% for the treated group. Increased level of T lymphocytes and NK cells was found in the TNF-alpha transfected bladders. In situ cytokine gene transfer provides significant protection against tumor growth. This approach may be useful to reduce the incidence of a subsequent tumor after endoscopic resection when used for prophylaxis.

Correlation between p53 mutations and HPV in bilharzial bladder cancer

Alterations of the p53 tumor suppressor gene are the most common genetic changes detected in human cancers as well as in papillary and invasive bladder cancer. Several studies have demonstrated an association between HPV infection and urological malignancies. In the present work, the p53 gene status was studied together with the frequency of HPV in 99 cases of Bilharzial bladder cancer [BBC] in Egypt and both were correlated to the clinicopathological features of the patients. SSCP and sequencing were used to screen the p53 gene for mutations at exons 4-10 and IHC was performed to detect protein overexpression. PCR was used for detection and typing of HPV-DNA in tumor samples. p53 mutations were detected in 33.3% of the studied cases whereas protein overexpression was detected in 35.6% of the cases. The highest concordance rate was observed in cases harboring mutations at exon 4 [87.5%]. Bilharzial infestation was obvious in 72.2% of the cases that showed mutations. Exon 8 showed the highest rate of mutation [32%] followed by exons 4 and 5 [22% each]. The commonest mutational event was G:C transversion [15/50] especially at CpG dinucleotides. A mutational hot spot was detected at exon 4, codons 72-73. HPV-DNA was detected in 48.97% of the cases the majority of which [64.6%] were of type 16. Significant correlation was found between p53 mutation and the pathological stage as well as p53 overexpression and tumor grade. Our results demonstrate that the mutational spectrum in BBC is different from that of bladder cancer in Western countries in many aspects and suggest an etiological role of HPV in this type of neoplasm. However, both HPV infection and p53 gene abnormalities may contribute to Bilharzial bladder carcinogenesis in an independent way.

Chromosome Aberrations in Cattle with Chronic Enzootic Haematuria

Chromosomal aberrations were investigated in 56 cattle with chronic enzootic haematuria (CEH) raised on pastures giving access to bracken fern. Of these animals, 27 were slaughtered and showed neoplastic lesions of the urinary bladder. Tumour tissue from 11 of the 27 cattle contained bovine papillomavirus type 2 (BPV-2) DNA. Increased numbers of chromosomal aberrations were seen in all animals with CEH, as compared with 30 control cattle that had had no access to bracken fern. The highest clastogenic effect was observed in cattle with urinary bladder cancer and evidence of BPV-2 DNA, suggesting that BPV-2 and bracken fern act synergistically in the production of chromosomal instability. In 19 of 20 animals with CEH, two bracken fern toxic compounds (quercitin and ptaquiloside) were demonstrated in urine, serum and milk.

Herpes simplex infection in urothelial carcinoma

Herpes simplex virus (HSV), a member of the Herpesviridae family, is a very common pathogen that can infect any site in the body. Urothelial carcinoma (UC) is a common malignancy of the urinary tract. The possibility of HSV infection in cases of UC has attracted little attention. In this study, we investigated the possible presence of HSV in UC and non-neoplastic urothelium. We examined the incidence of HSV infection in 100 samples of UC from 78 patients and 50 samples of non-neoplastic urothelium from 50 autopsy cases using immunohistochemical staining and amplification of DNA using polymerase chain reaction (PCR). Infection by HSV was detected in 39 of the 100 samples of UC (35 of 78 patients) using immunohistochemical staining and/or PCR analysis, in marked contrast with 1 of 50 samples of non-neoplastic urothelium. There was no significant relationship between infection by HSV and anatomical site, growth pattern or depth of invasion of UC, but the frequency of HSV infection was significantly higher in females than in males. Our findings indicate that UCs become infected with HSV much more easily than non-neoplastic urothelium.

Urothelial bladder carcinoma and viral infections: different association with human polyomaviruses and papillomaviruses

Bladder cancer is the second most commonly occurring genitourinary cancer in adults. The interaction of different carcinogenic and cocarcinogenic agents are responsible for bladder urothelial carcinoma: alcohol and smoking habits, Schistosoma haematobium infection, exposition to chemicals, analgesic and antineoplastic drugs prolonged use. Recently also viral infections have been associated to this pathology. In this study the correlation between viral infections and bladder carcinoma has been evaluated. A group of 32 patients affected by primary bladder neoplasia has been analysed. A control group of 20 autoptic samples of healthy bladder was analysed. The DNA of the following viruses has been searched by polymerase chain reaction (PCR): Adenovirus, Herpes simplex virus type 1 (HSV-1), Herpes simplex virus type 2 (HSV-2), Human Papillomaviruses (HPV), Polyomaviruses (BKV and JCV). In the examined population the association bladder carcinoma-HPV, found by others, has not been confirmed. The high percentage of human polyomaviruses present in the samples is a statistically significant data (p=0.0087) and allows to presume that BKV and JCV may play a role in the aetiology of bladder tumor. In particular the polyomavirus BK, which is found in significative percentage both in single infection (p=0.0036) and in co-infections with other viral species (p=0.035), may be an important co-factor in the pathogenesis of bladder carcinoma.

Presence of bovine papillomavirus type 2 DNA and expression of the viral oncoprotein E5 in naturally occurring urinary bladder tumours in cows

Samples of neoplastic and normal urothelium were obtained from cows originating from areas of southern Italy, a region in which chronic enzootic haematuria is endemic and bracken fern infestation is widespread. Specimens were analysed for bovine papillomavirus type 2 (BPV-2) DNA, BPV-2 E5 expression and telomerase activity. A total of 46 of 60 tumours and 17 of 34 normal bladder mucosa samples harboured BPV-2 DNA. Analysis of a subset of samples showed E5 protein expression and telomerase activity in tumour tissue only. No normal samples positive for BPV DNA showed E5 protein expression or telomerase activity, suggesting the presence of DNA in a latent state. Taken together, these data on naturally occurring bovine bladder tumours corroborate the hypothesis of their virus origin.

Chapter 9: Role of mucosal human papillomavirus in nongenital cancers

Established associations between human papillomavirus (HPV) and lower genital tract cancers provide a framework from which to evaluate a possible pathogenic role for the virus in cancers at nongenital sites. Proposed associations must fit coherently within the context of our current knowledge of the epidemiology and biology of HPV. In this article, insights obtained from studies of the etiologic link between mucosal-type HPV infection and four specific human cancers are described briefly. Specific characteristics, shared among cancers caused by HPV, are then used by extrapolation to discuss possible associations between certain other nongenital cancers and mucosal HPV infections in a manner intended to supplement, and in no way to supplant, the classic Hill criteria for causal inference.

Gene therapy for bladder cancer using E1B-55 kD-deleted adenovirus in combination with adenoviral vector encoding plasminogen kringles 1-5

Mutations or loss of heterozygosity of p53 are detected in approximately 50% of bladder cancers. E1B-55 kD-deleted adenovirus has been shown to kill tumour cells with defective p53 function while sparing normal cells. Here, we examined the cytolytic effect and replication of E1B-55 kD-deleted adenovirus, designated Ad5WS1, on human bladder cancer cell lines with various p53 status. Ad5WS1 caused more severe cytolytic effect and replicated more efficiently in J82 and TCC-SUP bladder cancer cells carrying mutant p53 compared with TSGH-8301 and BFTC-905 bladder cancer cells retaining wild-type p53. Introduction of dominant negative p53 into BFTC-905 cells rendered them more susceptible to Ad5WS1-induced cytolysis. Furthermore, cells susceptible to lysis caused by Ad5WS1 were not attributable to their greater infectability by adenovirus. Finally, Ad5WS1 suppressed the growth of TCC-SUP bladder tumour xenografts, which could be augmented when combined with replication-defective adenoviral vector encoding kringles 1-5 of plasminogen (K1-5), an angiogenic inhibitor. Taken together, our results show that E1B-55 kD-deleted adenovirus replicates and hence lyses bladder cancer cells with mutant p53 much more efficient than those with wild-type p53. Thus, E1B-deleted adenovirus may have therapeutic potential, especially in combination with adenoviral vector expressing K1-5, for the treatment of bladder cancer.

Selective reovirus killing of bladder cancer in a co-culture spheroid model

Up to 50% of the transitional cell carcinomas (TCC) express an activated EGF pathway involving MAP/MEK and RAF kinase thus providing a novel means to selectively eliminate transformed cells expressing such proteins. This EGF pathway expression phenotype was also confirmed in our MGH-U3 and room temperature-112 human TCC cell lines, which makes them a suitable model target for the reovirus oncolysis. We report here on an in vitro assay of co-culture spheroids using either human or rat TCC cells with their corresponding fibroblasts to examine the potential of viral selective lysis for TCC. Reovirus, a respiratory enteric orphan virus, which mammals are exposed to early in life, was used in this study. Selective killing of transformed versus normal cells was assayed by time-lapse photography, vital dye staining, immunohistochemistry, and MTT assay. In this in vitro bladder cancer model, reovirus selectively destroyed the transformed cells by lysis or induction of apoptosis. Based on these findings we have initiated an in vivo pre-clinical study on intravesical administration of reovirus in an animal model to further explore the effect of reovirus-mediated oncolysis of TCC.

Virotherapy clinical trials for regional disease: in situ immune modulation using recombinant poxvirus vectors

The ability of viruses to readily infect tumor cells both in vitro and in vivo has resulted in their study as antitumor agents through a variety of strategies. Replicating and conditionally replicating viruses and recombinant viruses encoding genes for toxins and/or prodrugs have been studied for their direct antitumor activity with promising results. However, to date, the lack of a targettable construct able to localize to all tumors following systemic administration has proven to be a major limitation in their use for metastatic disease. The ability of a variety of well-characterized viruses to serve as vectors for expression of tumor antigens and/or cytokines has also resulted in their study as immunotherapeutic agents. In this review, we discuss preclinical and clinical data that support the use of recombinant poxviruses as vectors for in situ tumor transfection with immune-enhancing cytokines and immune costimulatory antigens. We hypothesize that such an approach will ultimately lead to enhanced immune recognition of tumor and the development of an effective systemic antitumor immune response capable of eradicating primary and metastatic tumor foci.

[Immunohistochemical characteristics and a degree of differentiation of urinary bladder cancer]

17 cases of severe dysplasia and urinary bladder intraepithelial carcinoma, 15 cases of invasive well differentiated urothelial carcinoma, 14 cases of moderately differentiated and 10 cases of poorly differentiated carcinoma were studied immunohistochemically. The role of metalloproteinases in urinary bladder carcinoma is established. Correlation between proliferative activity, protease expression and the degree of tumor differentiation is found. Viral DNA of human papilloma of 16/18 types in severe dysplasia and carcinoma in situ was revealed by hybridization in situ method.

Identification of human uroplakin II promoter and its use in the construction of CG8840, a urothelium-specific adenovirus variant that eliminates established bladder tumors in combination with docetaxel

Uroplakins (UPs) are a group of integral membrane proteins that are synthesized as the major differentiation products of mammalian urothelium. UPII gene expression is bladder specific and differentiation dependent, but very little is known about its transcription response elements. To identify the promoter elements, a DNA fragment of 2239 bp upstream of the UPII gene was amplified by PCR and linked to a promoterless firefly luciferase reporter gene. Transient transfection experiments showed that the DNA segment located between -1809 and +1 bp resulted in preferential expression in bladder carcinoma cells with negligible expression in nonurothelial cells. This promoter was engineered into adenovirus (Ad) type 5 to drive the expression of the E1A and E1B genes and to create an attenuated replication-competent Ad variant, termed CG8840. Viral replication and the cytopathic effect of CG8840 were evaluated by virus yield and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays in bladder transitional cell carcinoma (TCC) cell lines RT4 and SW780; nonbladder cancer cell lines G361 (melanoma), LNCaP (prostate cancer), PA-1 (ovarian cancer), and U118 (brain cancer); and human primary cells including lung fibroblasts, bladder smooth muscle cells, and mammary epithelial cells. CG8840 replicated in and eliminated bladder TCC efficiently with high specificity (10,000:1) in comparison with nonbladder cells. The antitumor activity of CG8840 was examined in BALB/c nu/nu mice carrying s.c. human TCC xenografts. Intratumoral and i.v. administration of CG8840 in RT4 human bladder cancer xenografts caused significant (P < 0.01) inhibition of tumor growth. Synergistic antitumor efficacy was observed when CG8840 was combined with docetaxel, resulting in significant regression of RT4 bladder cancer xenograft tumors within 6 weeks after i.v. administration of CG8840 (3.33 x 10(9) plaque-forming units/animal on day 1) and docetaxel (20 mg/kg on days 2, 6, and 9). These results demonstrate the utility of the UPII promoter in the generation of urothelium-specific adenoviral vectors and provide a potential foundation for the development of bladder tumor-specific oncolytic viral therapies.

p53 codon 72 polymorphism and its association with bladder cancer

p53 codon 72 Arg homozygosity has been associated with increased risk of developing cervical cancer. This association has been tested in various human cancers with controversial results. In the present study we investigated the impact of this polymorphism in a population-based case-control study of bladder cancer. Using allele-specific polymerase chain reaction to detect the p53 codon 72 polymorphism, we tested peripheral blood samples from 50 patients with bladder cancer and 99 healthy individuals of similar age and from the same geographical region. Tumor specimens from all bladder cancer patients were examined for the presence of human papilloma virus (HPV). The distribution of p53 alleles in bladder cancer patients and in controls was statistically significant (P<0.002; odds ratio, 2.67; 95% confidence interval, 1.38-5.20), and homozygosity for arginine at residue 72 was associated with an increased risk for bladder cancer (P<0.00002; odds ratio, 4.69; 95% confidence interval, 2.13-10.41). The presence of HPV was found in six of the 50 patients (12%). This is the first study correlating p53 codon 72 polymorphism with bladder cancer. Our results provide evidence that this p53 polymorphism is implicated in bladder carcinogenesis and that individuals harboring the Arg/Arg genotype have an increased risk of developing bladder cancer.

The mechanism of the growth-inhibitory effect of coxsackie and adenovirus receptor (CAR) on human bladder cancer: a functional analysis of car protein structure

The coxsackie and adenovirus receptor (CAR) is identified as a high-affinity receptor for adenovirus type 5. We observed that invasive bladder cancer specimens had significantly reduced CAR mRNA levels compared with superficial bladder cancer specimens, which suggests that CAR may play a role in the progression of bladder cancer. Elevated CAR expression in the T24 cell line (CAR-negative cells) increased its sensitivity to adenovirus infection and significantly inhibited its in vitro growth, accompanied by p21 and hypophosphorylated retinoblastoma accumulation. Conversely, decreased CAR levels in both RT4 and 253J cell lines (CAR-positive cells) promoted their in vitro growth. To unveil the mechanism of action of CAR, we showed that the extracellular domain of CAR facilitated intercellular adhesion. Furthermore, interrupting intercellular adhesion of CAR by a specific antibody alleviates the growth-inhibitory effect of CAR. We also demonstrated that both the transmembrane and intracellular domains of CAR were critical for its growth-inhibitory activity. These data indicate that the cell-cell contact initiated by membrane-bound CAR can elicit a negative signal cascade to modulate cell cycle regulators inside the nucleus of bladder cancer cells. Therefore, the presence of CAR cannot only facilitate viral uptake of adenovirus but also inhibit cell growth. These results can be integrated to formulate a new strategy for bladder cancer therapy.

Human papillomaviruses 6/11, 16/18 and 31/33/51 are not associated with squamous cell carcinoma of the urinary bladder

OBJECTIVE

To assess high-risk human papillomavirus (HPV), mainly HPV type 16, 18, 31 and 33 (an important aetiological factor in squamous cell carcinoma, SCC, of the anogenital region) in SCC of the urinary bladder.

MATERIAL AND METHODS

Sixteen SCC from the urinary bladder were evaluated using non-isotopic in situ hybridization with a sensitive detection system for the presence of high-risk HPV 16/18, or 31/33/51, and for HPV6/11, a low-risk type commonly found in condylomata. Previously published studies were also reviewed and assessed.

RESULTS

No high-risk HPV was found in any of the SCC of the bladder evaluated. Previous reports identified nine HPV-positive SCC of a total of 105, including the present series. In four of these positive cases, HPV types were found that are considered a high risk in anogenital carcinomas.

CONCLUSION

From the present and previous results, we conclude that HPV has no major role in the pathogenesis of SCC of the urinary bladder.

Concomitant presence of bladder cancer and neurogenic bladder in a patient with HTLV-1 carrier: a case report

We describe a case of an HTLV-1 carrier who developed bladder cancer and neurogenic bladder. HTLV-1 is thought to alter host immune function and to contribute to the development of other malignancies. It is also sometimes reported that urinary symptoms precede pyramidal symptoms in patients with HAM. To our knowledge, concomitant presence of bladder cancer and neurogenic bladder in an HTLV-1 carrier has not been previously reported.

Investigation of human papillomavirus in transitional cell carcinomas of the urinary bladder in South Africa

AIM

To investigate the prevalence of human papillomavirus in transitional cell carcinoma of the urinary bladder in South Africa.

METHODS

Ninety-one archival samples of bladder transitional cell carcinoma were subjected to polymerase chain reaction (PCR) and non-isotopic in situ hybridisation (NISH) for the detection of human papillomavirus 6, 11, 16, 18, 31, and 33 genotypes.

RESULTS

HPV was detected in only one case with PCR. HPV was not detected in any of the cases subjected to the NISH system.

CONCLUSION

This study shows that although HPV has been shown to be associated with uterine cervical and esophageal squamous cell carcinomas in South Africa, this virus is not present in the transitional cell carcinoma of the urinary bladder in this geographical location. It is suggested that other factors, including nitrosamine exposure, p53 mutation, and additional unknown chromosomal events, may play a role in the carcinogenesis of this neoplasm in the bladder.

Postoperative immuno-gene therapy of murine bladder tumor by in vivo administration of retroviruses expressing mouse interferon-gamma

The murine MBT-2 bladder tumor model in syngeneic C3H/HeN mice was used to investigate the feasibility of gene therapy based on the delivery of interferon-gamma (IFN-gamma) in vivo by retroviral vectors. We constructed a recombinant retroviral vector pRUFneo/IFN-gamma, which was transfected into a retroviral packaging cell line psiCRE, to produce psiCRE/pRUFneo/IFN-gamma cells. The expressions of the neo and IFN-gamma genes were verified by reverse transcription-polymerase chain reaction and IFN-gamma was detected in the culture supernatant from psiCRE/pRUFneo/IFN-gamma cells. After receiving MBT-2 cells admixed with retroviral pRUFneoIFN-gamma supernatant, C3H/HeN mice exhibited lower tumor incidence, lower tumor mass, and higher survival rate, as well as higher antitumor responses compared to those injected with MBT-2 cells admixed with control retroviral supernatant. Moreover, the retroviral pRUFneoIFN-gamma supernatant was able to suppress the growth of rechallenged tumors in postoperated mice. Although the IFN-gamma protein secreted from psiCRE/pRUFneo/IFN-gamma cells partly contributes to the antitumor effect of retroviral pRUFneoIFN-gamma supernatant, the retroviruses carrying the IFN-gamma gene transduced MBT-2 cells in vivo, which may result in enhancing local IFN-gamma production from tumor cells. Because bladder is suitable for the intravesical instillation of therapeutic agents, in vivo administration of retroviral vectors encoding IFN-gamma may be explored for the treatment of bladder cancer.

[The study on relation of human papillomavirus and P53 expression with bladder transitional cell carcinoma]

OBJECTIVE

To study the relationship between the bladder transitional cell carcinoma and the human papillomavirus (HPV) types 6, 11, 16, 18 and P53.

METHODS

We used polymerase chain reaction (PCR) to test HPV type 6, 11, 16 and 18 infection from 75 cases of bladder cancer, and used immunohistochemistry method to detect P53 expression.

RESULTS

The positive rates of HPV types 6, 11, 16 and 18 were 6.7%, 5.3%, 33.3% and 6.7%, respectively. The positive rate of low risk HPV type (6/11) was 9.3% (7/75), and that of high risk HPV types (16/18) was 34.7% (26/75). There were 8 cases with two or three HPV types mixed infection, accounting for 10.6%, HPV types 6,11,16,18 in tumor metastasis group were significantly higher than that in non-metastasis group. The positive rates of HPV 16, 18 types in G3 were significantly higher than that in G1 and G2. HPV type 16 was the main type in bladder cancer. Positive rate of P53 expression was 44%.

CONCLUSIONS

These results implicated that the occurrence and development of bladder transitional cell carcinoma may be closely related to the high risk HPV type infection and P53 expression.

Calculus-producing and cytomegalovirus-infected nephrogenic adenoma of the bladder in a prepubertal renal transplant recipient

A 14-year-old prepubertal boy, a renal transplant recipient, was treated for a nephrogenic adenoma. His case is unique in that he is the second youngest renal transplant recipient diagnosed with a nephrogenic adenoma. In addition, the lesion was calculus producing, which has not been previously described, and contained cytomegalovirus inclusions, which has been described only once previously in association with a nephrogenic adenoma in a transplant patient.

Retrovirus type C in the mouse bladder carcinoma cell line MBT-2

PURPOSE

The presence of replicating type C retrovirus in MBT-2 mouse bladder carcinoma cells is reported. This MBT-2 tumor cell line is nowadays globally distributed. The cells have been and are still used to study various aspects of bladder cancer. While studying the phagocytic capacity of MBT-2 cells for BCG organisms by electron microscopic methods, the presence of this retrovirus was noticed.

MATERIALS AND METHODS

MBT-2 cells that were cultured in vitro as well as cells from intravesically and intradermally grown MBT-2 tumors from syngeneic mice were investigated using transmission electron microscopy (TEM) and scanning electron microscopy (SEM) techniques.

RESULTS

All samples including the earliest generation MBT-2 cells that could be traced from stocks of other research groups contained the C type retrovirus, suggesting a contamination in all available generations of the MBT-2 cell line.

CONCLUSIONS

As this tumor cell line is widely used in immunologic studies of the response to bladder cancer, it is important to consider the possible presence of type C viruses and associated antigens, since they could contribute to or interfere with the responses being measured. Studies should be initiated to determine whether viral antigen expression is involved in the immune rejection of MBT-2 bladder cancer. As a consequence, clinical implementation of immunological treatment strategies should not be based on results obtained with the MBT-2 model alone, but preferably should be confirmed with other (bladder) carcinoma models.

DNA methylation and expression of LINE-1 and HERV-K provirus sequences in urothelial and renal cell carcinomas

Since DNA methylation is considered an important mechanism for silencing of retroelements in the mammalian genome, hypomethylation in human tumours may lead to their reactivation. The methylation status of LINE-1 retroposons was determined in 73 samples of urinary bladder cancers, 34 specimens of renal cell carcinoma and in the corresponding normal tissues by Southern blot analysis. LINE-1 sequences were strongly methylated in normal tissues and were significantly hypomethylated in 69 (95%) urothelial carcinomas, but in none of the renal carcinomas. Hypomethylation in bladder cancers was independent of stage and tended to increase with grade. The methylation status of HERV-K proviral DNA in normal and transformed urothelial cells paralleled that of LINE-1 sequences (r2 = 0.87). It was shown by ligation-mediated polymerase chain reaction that hypomethylation also extended to the LINE-1 promoter sequence located at the 5'-ends of full-length elements which is repressed by methylation in somatic tissues. Accordingly, full-length LINE-1 transcripts were detected by Northern blot analysis in two urothelial carcinoma cell lines. In contrast, transcripts from HERV-K proviruses were restricted to teratocarcinoma cell lines. Our data indicate that genome-wide DNA hypomethylation is an early change in urothelial carcinoma, but is absent from renal cell carcinoma. The coordinate changes of LINE-1 and HERV-K DNA methylation suggest that hypomethylation in urothelial cancer affects a variety of different retroelements to similar extents. We speculate that decreased methylation of LINE-1 retroelements, in particular, may contribute to genomic instability in specific human tumours such as urothelial carcinoma by rendering these normally repressed sequences competent for transcription and recombination.

Low frequency of human papillomavirus infection in initial papillary bladder tumors

The involvement of human papillomavirus (HPV) in bladder cancer remains controversial. We previously reported detection of L1-HPV DNA in 39% of bladder cancers of mixed grade and stage. To clarify the possible etiologic role of HPV we studied, using the same technique, a more homogeneous group of initial low-stage tumors. We investigated a total of 187 newly diagnosed superficial papillary bladder tumors for the presence of L1-HPV DNA by the polymerase chain reaction method and hybridization with specific probes for HPV 6, 11, 16, 18, 33. HPV DNA was detected in 16 (8.5%) of the 187 specimens tested, although in a low copy number compared with SiHa cervical cancer cells used as control. HPV type 16 was observed in eight tumors while HPV type 6 and type 11 were each observed in three tumors. Two tumor specimens contained two types of HPV: one tumor hybridized with type 6 and 16 and the other with type 11 and 18. This low rate of HPV detection (8.5%) in initial tumors does not favor a prominent role for HPV in bladder carcinogenesis.

[The detection of high risk human papillomaviruses in papillary transitional cell carcinoma of urinary bladder]

OBJECTIVE

To investigate the histological evidence of high risk human papillomavirus infection in bladder cancer.

METHODS

52 cases of papillary transitional cell carcinoma of the urinary bladder were studied for the incorporation of high risk human papillomavirus type 16 and type 18 DNA by non-isotopic in situ hybridization (NISH).

RESULTS

19 of 52 cases (36.5%) were positive for HPV DNA with punctuate and/or diffuse purple-blue staining in the nucleus of cancer cells, including two cases positive both for HPV16/18. HPV DNA were predominantly expressed in superficial tumors. Among these positive tumors, adjacent normal epithelium and Brunn's nests also showed positive staining. Morphologically, HPV positive cells existed in the whole layer of papillary tumor cells, 3 of them presented koilocytoid change.

CONCLUSIONS

HPV infection might be a common event in urinary bladder and a potential factor for carcinogenesis of bladder cells.

Human papillomavirus associated with bladder carcinoma? Analysis by polymerase chain reaction

BACKGROUND

The aim of the present study was to assess the possible etiologic role of human papillomaviruses (HPV) in bladder tumors.

METHODS

Forty-two fresh biopsy specimens from different grades and stages of bladder tumor cases and 10 normal bladder mucosa biopsies were studied. Specimens were analyzed by polymerase chain reaction (PCR) with HPV-specific general primer set for the detection of viral DNA. Polymerase chain reaction-positive samples were also tested with HPV 16- and 18-specific primers by the same method.

RESULTS

We found two samples (4.8%) containing HPV DNA among the TaG1 bladder tumors. All other specimens, including the control group, were found to be negative by PCR. Neither of the two HPV-positive patients had immune deficiency and/or genital wars. Human papillomavirus 16 was detected by type-specific primers in one sample, but the other HPV-positive sample could not be typed.

CONCLUSIONS

The low prevalence of HPV in this and many previous studies does not support an etiologic role of HPV in bladder carcinogenesis. We detected the virus in two early stage tumors, but none was detected in the high-grade samples. However, to clarify the positivity of HPV in these occasional cases, future studies must be designed by using in situ PCR techniques, including samples from tumors and normal bladder mucosa from the same patient.

Detection of human papillomavirus DNA in urinary bladder carcinoma by in situ hybridisation

AIMS

To investigate the sensitivity of an in situ hybridisation system to detect human papillomavirus (HPV) infection in transitional cell bladder cancer and to evaluate the advantages of analysing multiple biopsies; to examine the correlation between HPV tumour infection detected by in situ hybridisation and the presence of serum anti-HPV antibodies detected by enzyme linked immunosorbent assay (ELISA); and to relate the presence of viral infection to grade, stage, and follow up in cases of bladder cancer.

METHODS

The in situ hybridisation technique was used with broad spectrum and type specific (6/11, 16/18, 31/33/35) probes against HPV DNA in formalin fixed, paraffin embedded tissues from 43 cases of bladder cancer. The results were analysed for the presence and type of papillomavirus and correlated with clinicopathological variables.

RESULTS

The presence of HPV DNA was identified by the in situ hybridisation technique in 17 of 43 cases of bladder cancer; 12 of these were serum antibody positive and 10 had had multiple biopsies. Fifteen of the cases that were negative for HPV DNA by in situ hybridisation had positive serum serology when tested by ELISA. In 14 cases, the HPV was either types 16/18 or types 31/33/35, both of which carry high oncogenic risk. The stage (p < 0.05) and grade (NS) of the tumour and the outcome on follow up (p < 0.05) were correlated with the presence of HPV infection.

CONCLUSIONS

ELISA is not useful in identifying patients with HPV positive bladder cancer, but the use of several probes and multiple biopsies increases the detection rate of HPV in neoplastic tissues. The association between tumour virus infection and high grade/high stage tumours and worse outcome suggests that HPV infection of neoplastic tissue has a negative effect on the behaviour and evolution of transitional cell bladder carcinoma.

[Study of human papillomavirus via chemiluminescence technic and polymerase chain reaction in transitional cell carcinoma of the bladder]

INTRODUCTION

The exact ethiology of bladder carcinoma isn't yet known; an implication of human papillomavirus (HPV) has been recently hypothesized.

MATERIALS AND METHODS

In this study HPV-DNA was investigated in urethral secretion and in bladder carcinoma of 37 patients. The analysis was performed by in vitro hybridization (chemiluminescent assay) and Polymerase Chain Reaction in order to detect HPV 6, 11, 16, 18, 31, 33 through specific primers.

RESULTS

On 3 out of 37 patients (8.1%) we found the presence of HPV-DNA, only in bladder T.U.R. and not in the corresponding urethral swab.

CONCLUSIONS

Our data suggest that human papillomavirus is unlikely to be involved in the pathogenesis of transitional cell carcinoma, in agreement with most European and American research groups.

Prevalence of papillomavirus, Epstein-Barr virus, cytomegalovirus, and herpes simplex virus type 2 in urinary bladder cancer

Recent epidemiological studies suggest that the risk for urological malignancies may be related to the exposure to infectious agents. Human Papillomaviruses type 16 and 18 (HPV 16, HPV 18), Epstein-Barr virus (EBV), cytomegalovirus (CMV) and herpes simplex virus type 2 (HSV-2) have been suggested previously as cofactors in the pathogenesis of some malignancies in humans. The present paper, the presence of HPV 16, HPV 18, EBV, CMV and HSV-2 genomes was investigated in a panel of 35 biopsies from urinary bladder carcinomas using the polymerase chain reaction (PCR). Sequences of EBV, HPV, CMV and HSV-2 genomes were detected in 34%, 31%, 11% and 9% of tissue samples respectively, while in 20% of patients we found more than one viral infection. Absence of viral genomes was found in normal bladder. To our knowledge, this is the first report concerning the association of EBV, CMV and HSV-2 with bladder cancer. This finding may raise the question whether such viral infection may contribute to development and progression of some types of urological malignancies in humans.

[Prognostic factors of infiltrating tumors of the bladder]

In France, invasive bladder cancer is the more frequent urologic malignancy after prostate carcinoma. Treatment of bladder cancer is radical cystectomy. New therapeutic approaches such as chemoradiation combination for a conservative procedure, neoadjuvant or adjuvant chemotherapy are still developing. In this way, a rigorous selection of patients is needed. This selection is based on prognostic criteria that could be divided into four groups: i) the volume of the tumor including the tumor infiltration depth, the nodal status, the presence or not of hydronephrosis and the residual tumor mass after transuretral resection; ii) the histologic aspects of the tumor including histologic grading, the presence or not of an epidermoid metaplasia, of in situ carcinoma or of thrombi; iii) the expression of tumor markers (tissue polypeptide antigen, bladder tumor antigen); iv) the biologic aspects of the tumor as ploidy, cytogenetic abnormalities, expression of Ki67, expression of oncogenes or tumor suppressor genes, expression of tumor antigens or growth factor receptors. This paper reviews the prognostic value of the various parameters.

Lack of evidence for a role of human papillomaviruses in transitional cell carcinoma of the bladder

PURPOSE

In view of the conflicting results reported in the literature, we assessed the involvement of human papillomaviruses (HPV) in the development of transitional cell carcinoma of the bladder.

MATERIALS AND METHODS

A total of 58 bladder papillomatous proliferations was histologically examined and analyzed for the presence of HPV deoxyribonucleic acid (DNA) sequences by Southern blot hybridization and the polymerase chain reaction (PCR) method.

RESULTS

Typical features of condyloma acuminatum were observed in the bladder specimen of a patient with urethral condylomatosis. Of the specimens 57 had histological features of transitional cell carcinoma but no known signs of HPV infection. HPV-6 DNA was detected in the condylomatous tumor. However, no HPV DNA was detected in the 57 bladder cancers by Southern blot hybridization and polymerase chain reaction.

CONCLUSIONS

These findings do not support an etiological role of HPV in the development of transitional cell bladder cancer.

Prevalence of six types of human papillomavirus in inverted papilloma and papillary transitional cell carcinoma of the bladder: an evaluation by polymerase chain reaction

AIMS

To study the prevalence of high risk oncogenic human papillomaviruses (HPV) in inverted papilloma and papillary transitional cell carcinoma of the bladder.

METHODS

Ten cases of inverted papilloma and 20 cases of papillary transitional cell carcinoma of the bladder from Chinese patients in Hong Kong were examined for the presence of HPV type 6, 11, 16, 18, 31, and 33 genomes using the polymerase chain reaction and HPV type specific primer probe combinations on paraffin wax embedded biopsy specimens.

RESULTS

Of the 10 cases of inverted papilloma, cases 1 and 6 showed the presence of HPV types 16 and 18, respectively. Six of the 20 papillary transitional cell carcinomas were positive for HPV type 18. The other HPV types were not detected.

CONCLUSIONS

HPV type 18 was found in 60% and 30% of cases of inverted papilloma and papillary transitional cell carcinoma of the bladder, respectively. These tumours were rarely associated with HPV types 6, 11, 16, 31, and 33. The role of HPV type 18 in oncogenesis of inverted papilloma and transitional cell carcinoma of the bladder requires further studies.

Human papillomavirus and bladder cancer

Human papillomavirus (HPV) deoxyribonucleic acid (DNA) has been originally detected in urothelial carcinomas of the bladder in immunocompromized patients. Studies from the general population showed a variable incidence of high risk HPV DNA which ranged from 2.5% to 81%, with HPV 16 DNA occurring more frequently. HPV DNA was detected in both papillary and invasive cancers, although in our experience the overall incidence was low. Most HPV positive cases were of high grade and stage with significant reduced survival or increased recurrence rate after transurethral resection. These results indicate an additional prognostic value of viral infection in bladder cancer. In addition, molecular studies suggest that the HPV related oncoproteins E6 and E7 play a role in bladder carcinogenesis via inactivation and/or degradation of p53 and pRb suppressor gene-associated proteins. The purpose of this review is to provide a brief summary of what is known about HPV and bladder cancer, and to address issues germane to the translation of this information to patient management.

Two cytodifferentiation agent-induced pathways, differentiation and apoptosis, are distinguished by the expression of human papillomavirus 16 E7 in human bladder carcinoma cells

Many transformed cells have been found to lose the capacity to proliferate and undergo differentiation following exposure to hybrid polar agents. This study investigates the mechanism by which hexamethylene bisacetamide (HMBA) suppresses the proliferation of the human bladder carcinoma line, T24. We found that following a 24-h exposure to HMBA, T24 proliferation was inhibited, and cells arrested in G1 phase and underwent morphological maturation. HMBA-induced cessation of proliferation was mediated, in part, by effects on cell cycle regulatory proteins. In T24 cells cultured without HMBA, E2F complexes predominantly with p107. In culture with inducer, p107 protein decreased, pRB and p130 were converted to underphosphorylated forms, and E2F was shifted into complexes with pRB and p130. To determine whether the formation of pRB:E2F and p130:E2F complexes was required for the HMBA-induced G1 arrest, the ability of the pocket proteins to bind E2F was blocked by enforced expression of human papillomavirus 16 E7. Following culture with HMBA, the T24 clones expressing E7 died, whereas vector-alone T24 clones arrested in G1 phase. T24/E7-1 cells did not form pRB:E2F or p130:E2F complexes upon culture with HMBA; rather, E2F was present in its free form. T24/E7-1 cells cultured with HMBA initially accumulate in G1. By day 2, they have entered into S phase, and by day 3, over 80% of the cells became apoptotic. Taken together, these studies enlarge the repertoire of demonstrated developmental pathways that may be triggered in transformed cells, depending upon their molecular status, and may provide potential therapeutic opportunities for cancer.

Human papillomavirus and schistosomiasis associated bladder cancer

AIMS

To determine the human papillomavirus DNA status of schistosomal associated squamous cell carcinoma of the urinary bladder in South Africa.

METHODS

Twenty five archival samples of bladder squamous cell carcinoma associated with Schistosoma haematobium were subjected to non-isotopic in situ hybridisation and the polymerase chain reaction for the detection of human papillomavirus 6, 11, 16, 18, 31, and 33 genotypes.

RESULTS

Using these two techniques, none of the 25 cases was shown to harbour human papillomavirus DNA.

CONCLUSIONS

This study abrogates the role of human papillomavirus in schistosoma associated bladder carcinoma in South Africa. It is suggested that other factors including nitrosamine exposure, p53 mutation, and additional unknown chromosomal events play a major role in the development of this parasite associated neoplasm.

Human papillomavirus 16 and 18 infection is absent in urinary bladder carcinomas

OBJECTIVE

The role of human papillomavirus (HPV) in the pathogenesis of bladder neoplasia remains controversial. Studies to date have mainly utilized polymerase chain reaction and DNA blot techniques to detect HPV DNA. The detection rates have varied from 0 to 81%. One of the major limitations of these techniques is that they lack topographic information. We have used a highly sensitive in situ hybridization (ISH) technique which detects single copies of viral genome and provides topographic information for investigation of HPV infection in bladder carcinomas.

MATERIALS AND METHODS

Thirty-one samples of formalin-fixed paraffin-embedded bladder carcinomas (4 adenocarcinomas, 5 squamous cell and 22 transitional cell carcinomas) were examined using non-isotopic ISH with biotin-labelled DNA probes of HPV 16 and 18 subtypes. HPV-positive skin and anal carcinoma samples were used as controls.

RESULTS AND CONCLUSIONS

No positive signals for HPV 16 or 18 were detected in any of the bladder carcinoma samples. Given the sensitivity of the technique, the result indicates that HPV 16 and 18 are not implicated in the development of bladder neoplasia compared to certain other epithelial malignancies. The possibility that other subtypes of HPV contribute to bladder epithelial carcinogenesis remains to be clarified.

Human papillomavirus and bladder cancer

Bladder cancer remains an important cause of oncological morbidity and mortality in women. Known etiological agents include smoking and exposure to certain industrial chemical compounds, though the origin of the majority of cases remains unknown. Human papillomavirus infection is also common in women and has been closely linked to the development of carcinoma of the cervix. It has been suggested that infection with HPV may also be an important factor in the subsequent development of bladder cancer. A number of studies using various techniques of molecular biology have looked at the relationship between HPV infection and bladder cancer. Although the results are somewhat conflicting, the overall picture would suggest little involvement of HPV in the evolution of bladder cancer, except possibly in a small group of patients who are immunocompromised.

The aetiological significance of human papillomavirus in bladder cancer

OBJECTIVE

To determine the prevalence of human papillomavirus (HPV) DNA types 6, 11 and 16 in histological sections of human bladder cancer.

MATERIALS AND METHODS

Fifty-five formalin-fixed, paraffin-embedded bladder tumour specimens were analysed for the presence of HPV infection using Southern blotting DNA hybridization and radiolabelled probes for HPV DNA types 6/11 and 16.

RESULTS

Despite the detection of HPV DNA type 6, 11 and 16 in positive control samples and the successful detection of HPV DNA in anogenital cancer using the same technique, no HPV DNA was found in any of the bladder tumour specimens examined.

CONCLUSIONS

Using a technique with proven efficacy in the detection of HPV DNA from histological specimens, no HPV DNA was present in any of the bladder tumours examined. This finding is in agreement with most recently published studies suggesting that HPV has no significant role in the development of human bladder cancer.

Suppression of human bladder cancer growth by increased expression of C-CAM1 gene in an orthotopic model

Recently, we demonstrated that an immunoglobulin-like cell adhesion molecule, C-CAM, acts as a tumor suppressor in prostate cancer. It is known that C-CAM is expressed in many epithelial cell types. In this study, we tested the possibility that C-CAM may also suppress bladder cancer progression. We used an orthotopic tumor model, which provides a relevant organ condition for examining the interaction between primary tumor cells and their microenvironment; this interaction has a critical impact on the behavior of carcinoma. We constructed a recombinant adenovirus expressing C-CAM1 (an isoform of C-CAM) and infected the 253J B-V cell line, a tumorigenic human bladder carcinoma subline. In vitro, C-CAM1 protein was detected in C-CAM1 adenovirus-infected cells but not in antisense control virus-infected cells, and the levels of expression showed dose dependency. When these cells were injected orthotopically in nude mice, we found that the increased expression of C-CAM1 in the 253J B-V cells repressed the growth of 253J B-V-induced tumors. Taken together, these data indicate that C-CAM1 is a potent tumor suppressor in human bladder cancer.

Human papillomavirus infection and transitional cell carcinoma of the bladder. Immunohistochemistry and in situ hybridization

The aim of the present research was to investigate human papillomavirus (HPV) infection by means of immunohistochemistry and in situ hybridization in 76 bladder cancer specimens. A biotinylated DNA probe that recognizes HPV 6/11, HPV 16/18 and HPV 31/33/35 was used for in situ hybridization. A polyclonal antibody recognizing HPV capsid antigen (HPVcAg) was used for immunohistochemistry. In situ hybridization and immunohistochemistry were developed by alkaline phosphatase and immunogold-silver techniques respectively. Our results showed that 25 (32.8%) out of 76 bladder carcinoma specimens reacted with HPVcAg. Twelve (15.7%) out of 76 cases were positive for HPV 16/18-DNA using non-isotopic in situ hybridization. Sixteen cases had koilocytosis. No positive signals were found for HPV 6/11 or 31/33/35-DNA probes.

Do human papillomaviruses have a role in the pathogenesis of bladder carcinoma?

PURPOSE

Since little is known of the associations between bladder carcinoma and human papillomaviruses (HPVs), data on the role of HPV in bladder carcinogenesis are controversial. We attempted to clarify whether HPVs are present in bladder carcinomas.

MATERIALS AND METHODS

We examined 36 specimens of bladder carcinoma for HPV positivity by the polymerase chain reaction method.

RESULTS

HPV-16 deoxyribonucleic acid was detected in 1 specimen (3%) of a transitional cell carcinoma from a 37-year-old woman who had concomitant squamous cell carcinoma of the uterine cervix with positive para-aortic lymph node metastasis. The cervical tumor, bladder tumor and para-aortic lymph node metastasis were all positive for the same type of HPV.

CONCLUSIONS

On the basis of this low rate of HPV detection (3%), HPVs are not likely to have a prominent role in carcinogenesis of the bladder.