Prevalence of Merkel Cell Polyomavirus (MCPyV) in the Oral Cavity Biopsies in Northern Iran.

OBJECTIVE: Infection with human tumor viruses is one of the hypothesized causes of cancer. The current investigation aimed to explore the presence and quantitative analysis of a new human tumor virus, Merkel cell polyomavirus (MCPyV) in tissue samples of 114 patients with oral cavity lesions including oral squamous cell carcinoma (OSCC), oral lichen planus (OLP), Dysplasia and oral irritation fibroma (OIF) in Northern Iran. METHODS: From 114 formalin fixed paraffin embedded samples; 35 with SCC, 29 with OLP, 14 with dysplasia and 36 with OIF were cut, deparaffinized and DNA was extracted. Quantitative detection of MCPyV large T antigen was performed by absolute quantitative Real-Time PCR. RESULT: MCPyV DNA was detected in 30.6% (n: 11/36) of IF, 24.1% (n; 7/29) of OLP, 21.4% (n:3/14) of dysplasia and 20% (n;7/35) of OSCC samples. The mean MCPyV DNA copy number was 2.32×10-2 ± 3.97 ×10-2, 2.02×10-2 (SD=3.13×10-2), 2.69×10-4 (SD=2.51×10-4), and 2.56×10-4 (SD=6.73×10-4) per cell in OSCC, dysplasia and both of OLP and OIF samples, respectively (P=0.76). CONCLUSION: This study provides the first data from Iran regarding the presence of MCPyV genome in oral cavity lesions and oral cancer. These results also emphasize that MCPyV has an active role in the occurrence of oral lesions and progression to cancer. Further studies should be carried out to clarify the role of MCPyV in oral cavity lesions.

Molecular evolution of fibropapilloma-associated herpesviruses infecting juvenile green and loggerhead sea turtles.

Chelonid Alphaherpesvirus 5 (ChHV5) has long been associated with fibropapillomatosis (FP) tumor disease in marine turtles. Presenting primarily in juvenile animals, FP results in fibromas of the skin, connective tissue, and internal organs, which may indirectly affect fitness by obstructing normal turtle processes. ChHV5 is near-universally present in tumorous tissues taken from affected animals, often at very high concentrations. However, there is also considerable asymptomatic carriage amongst healthy marine turtles, suggesting that asymptomatic hosts play an important role in disease ecology. Currently, there is a paucity of studies investigating variation in viral genetics between diseased and asymptomatic hosts, which could potentially explain why only some ChHV5 infections lead to tumor formation. Here, we generated a database containing DNA from over 400 tissue samples taken from green and loggerhead marine turtles, including multiple tissue types, a twenty year time span, and both diseased and asymptomatic animals. We used two molecular detection techniques, quantitative (q)PCR and nested PCR, to characterize the presence and genetic lineage of ChHV5 in each sample. We found that nested PCR across multiple loci out-performed qPCR and is a more powerful technique for determining infection status. Phylogenetic reconstruction of three viral loci from all ChHV5-positive samples indicated widespread panmixia of viral lineages, with samples taken across decades, species, disease states, and tissues all falling within the same evolutionary lineages. Haplotype networks produced similar results in that viral haplotypes were shared across species, tissue types and disease states with no evidence that viral lineages associated significantly with disease dynamics. Additionally, tests of selection on viral gene trees indicated signals of selection dividing major clades, though this selection did not divide sample categories. Based on these data, neither the presence of ChHV5 infection nor neutral genetic divergence between viral lineages infecting a juvenile marine turtle is sufficient to explain the development of FP within an individual.

Dynamics of Virus Shedding and In Situ Confirmation of Chelonid Herpesvirus 5 in Hawaiian Green Turtles With Fibropapillomatosis.

Cancers in humans and animals can be caused by viruses, but virus-induced tumors are considered to be poor sites for replication of intact virions (lytic replication). Fibropapillomatosis (FP) is a neoplastic disease associated with a herpesvirus, chelonid herpesvirus 5 (ChHV5), that affects green turtles globally. ChHV5 probably replicates in epidermal cells of tumors, because epidermal intranuclear inclusions (EIIs) contain herpesvirus-like particles. However, although EIIs are a sign of herpesvirus replication, they have not yet been firmly linked to ChHV5. Moreover, the dynamics of viral shedding in turtles are unknown, and there are no serological reagents to confirm actual presence of the specific ChHV5 virus in tissues. The investigators analyzed 381 FP tumors for the presence of EIIs and found that overall, about 35% of green turtles had lytic replication in skin tumors with 7% of tumors showing lytic replication. A few (11%) turtles accounted for more than 30% cases having lytic viral replication, and lytic replication was more likely in smaller tumors. To confirm that turtles were actively replicating ChHV5, a prerequisite for shedding, the investigators used antiserum raised against F-VP26, a predicted capsid protein of ChHV5 that localizes to the host cell nucleus during viral replication. This antiserum revealed F-VP26 in EIIs of tumors, thus confirming the presence of replicating ChHV5. In this light, it is proposed that unlike other virus-induced neoplastic diseases, FP is a disease that may depend on superspreaders, a few highly infectious individuals growing numerous small tumors permissive to viral production, for transmission of ChHV5.

Oral fibroma with HPV-associated epithelial dysplasia: even in fibromas you should look for the unexpected.

Fibromas are the most common soft tissue lesions of the oral cavity and are generally attributed to trauma. Koilocytic dysplasia refers to human papillomavirus (HPV)-related epithelial cytopathic effect. Koilocytic dysplasia is considered neoplastic. Herein, we report a case of oral fibroma with HPV-induced dysplastic changes of the surface epithelium confirmed by immunohistochemical stains for p16 and p53 as well as HPV in situ hybridization.

Characterization of a novel polyomavirus isolated from a fibroma on the trunk of an African elephant (Loxodonta africana).

Viruses of the family Polyomaviridae infect a wide variety of avian and mammalian hosts with a broad spectrum of outcomes including asymptomatic infection, acute systemic disease, and tumor induction. In this study a novel polyomavirus, the African elephant polyomavirus 1 (AelPyV-1) found in a protruding hyperplastic fibrous lesion on the trunk of an African elephant (Loxodonta africana) was characterized. The AelPyV-1 genome is 5722 bp in size and is one of the largest polyomaviruses characterized to date. Analysis of the AelPyV-1 genome reveals five putative open-reading frames coding for the classic small and large T antigens in the early region, and the VP1, VP2 and VP3 capsid proteins in the late region. In the area preceding the VP2 start codon three putative open-reading frames, possibly coding for an agnoprotein, could be localized. A regulatory, non-coding region separates the 2 coding regions. Unique for polyomaviruses is the presence of a second 854 bp long non-coding region between the end of the early region and the end of the late region. Based on maximum likelihood phylogenetic analyses of the large T antigen of the AelPyV-1 and 61 other polyomavirus sequences, AelPyV-1 clusters within a heterogeneous group of polyomaviruses that have been isolated from bats, new world primates and rodents.

Evidence of regression of fibropapillomas in juvenile green turtles Chelonia mydas caught in Niterói, southeast Brazil.

Fibropapillomatosis is a disease characterized by cutaneous tumors affecting all marine turtle species, but mostly Chelonia mydas. The disease was first reported in 1938, and since then, the number of sightings has been increasing over the years. This disease can cause many complications in the affected animal and can lead to death, and is thus included in the many threats to marine turtle populations. It is still not known for certain what causes this disease, although many studies indicate a herpesvirus as the main etiologic agent. The incidence of fibropapillomatosis is rarely reported in adults, leading to speculations that there may be a cure for the disease or that the animals die before reaching adulthood. In this paper, 2 cases of fibropapillomatosis regression are reported from juvenile C. mydas caught between July 2008 and July 2010 in the coastal zone of Itaipu, Niterói, Rio de Janeiro, Brazil. These individuals were identified photographically upon recapture. One individual had a total regression (disappearance) of external papilloma within 164 d between first capture and recapture, and the other individual had a partial regression (decrease in size) observed within 13 to 188 d of recapture. The mechanism that triggers the regression is still unknown but is likely to be an immune system response or removal of the tumor promoter. There are few reported cases of regression in the world, and constant monitoring through mark-recapture is necessary to assess whether the marine turtles affected by this disease have real chances of survival.

Pathology of tumors in fish associated with retroviruses: a review.

Thirteen proliferative diseases in fish have been associated in the literature with 1 or more retroviruses. Typically, these occur as seasonal epizootics affecting farmed and wild fish, and most lesions resolve spontaneously. Spontaneous resolution and lifelong resistance to reinfection are 2 features of some piscine retrovirus-induced tumors that have stimulated research interest in this field. The purpose of this review is to present the reader with the epidemiological and morphological features of proliferative diseases in fish that have been associated with retroviruses by 1 or more of the following methods: detection of C-type retrovirus-like particles or reverse transcriptase activity in tumor tissues; successful tumor transmission trials using well-characterized, tumor-derived, cell-free inocula; or molecular characterization of the virus from spontaneous and experimentally induced tumors. Two of the diseases included in this review, European smelt spawning papillomatosis and bicolor damselfish neurofibromatosis, at one time were attributed to a retroviral etiology, but both are now believed to involve additional viral agents based on more recent investigations. We include the latter 2 entities to update the reader about these developments.

First histological and virological report of fibropapilloma associated with herpesvirus in Chelonia mydas at Príncipe Island, West Africa.

Marine turtle fibropapillomatosis is an emerging disease that affects marine turtles worldwide. This report describes the histopathological features and involvement of chelonid fibropapilloma-associated herpesvirus in marine turtle fibropapillomatosis detected in the green turtle Chelonia mydas at Príncipe Island, Gulf of Guinea. The histopathological findings confirmed the presence of fibropapillomas with both verrucous and fibromatous subtypes. Quantitative real-time PCR was used for detection of chelonid fibropapilloma-associated herpesvirus in tissue samples (n = 18) collected from afflicted (n = 10) and apparently healthy turtles (n = 2), revealing 94.4% positive samples, confirming the presence of viral sequences not only in fibropapillomatosis lesions but also in the skin of apparently healthy animals.

Pathology and immunohistochemistry of papillomavirus-associated cutaneous lesions in Cape mountain zebra, giraffe, sable antelope and African buffalo in South Africa.

Skin lesions associated with papillomaviruses have been reported in many animal species and man. Bovine papillomavirus (BVP) affects mainly the epidermis, but also the dermis in several species including bovine, the best-known example being equine sarcoid, which is associated with BVP types 1 and 2. This publication describes and illustrates the macroscopic and histological appearance of BPV-associated papillomatous, fibropapillomatous or sarcoid-like lesions in Cape mountain zebra (Equus zebra zebra) from the Gariep Dam Nature Reserve, 2 giraffes (Giraffa camelopardalis) from the Kruger National Park, and a sable antelope (Hippotragus niger) from the Kimberley area of South Africa. An African buffalo (Syncerus caffer) cow from Kruger National Park also had papillomatous lesions but molecular characterisation of lesional virus was not done. Immunohistochemical staining using polyclonal rabbit antiserum to chemically disrupted BPV-1, which cross-reacts with the L1 capsid of most known papillomaviruses, was positive in cells of the stratum granulosum of lesions in Giraffe 1, the sable and the buffalo and negative in those of the zebra and Giraffe 2. Fibropapillomatous and sarcoid-like lesions from an adult bovine were used as positive control for the immunohistochemistry and are described and the immunohistochemistry illustrated for comparison. Macroscopically, both adult female giraffe had severely thickened multifocal to coalescing nodular and occasionally ulcerated lesions of the head, neck and trunk with local poorly-circumscribed invasion into the subcutis. Necropsy performed on the 2nd giraffe revealed neither internal metastases nor serious underlying disease. Giraffe 1 had scattered, and Giraffe 2 numerous, large, anaplastic, at times indistinctly multinucleated dermal fibroblasts with bizarre nuclei within the sarcoid-like lesions, which were BPV-1 positive in Giraffe 1 and BPV-1 and -2 positive in Giraffe 2 by RT-PCR. The sable antelope presented with a solitary large lesion just proximal to the right hind hoof, which recurred after excision, and was BPV-1 positive by RT-PCR. Other wart-like growths were present elsewhere on the body. The Cape mountain zebra either succumbed from their massive lesions or were euthanased or removed from the herd because of them. The lesions were BPV-1 and/or -2 positive by RT-PCR. The buffalo lesions were wart-like papillomatous projections in the inguinal and udder region. Stratum granulosum cells that stained immunohistochemically positive in the various species appeared koilocyte-like, as described in human papillomaviral lesions.

Analysis of rhesus rhadinovirus microRNAs expressed in virus-induced tumors from infected rhesus macaques.

Rhesus rhadinovirus (RRV), a primate gamma-herpesvirus related to human Kaposi's sarcoma-associated herpesvirus (KSHV), causes a similar pattern of pathogenesis. Previously, RRV was shown to express 7 pre-microRNAs (pre-miRNAs) in latently infected cells. Using deep sequencing, we analyzed the pattern of small RNA expression in vivo using latently RRV-infected B-cell lymphoma and retroperitoneal fibromatosis tissues. We identified 15 virally encoded pre-miRNAs in both tumors, including all previously reported RRV pre-miRNAs. Although all 15 RRV pre-miRNAs, like all 12 KSHV pre-miRNAs, are located 3' to the conserved viral ORF71 gene and in the same transcriptional orientation, only one RRV miRNA is homologous to a KSHV miRNA. One previously identified RRV miRNA, miR-rR1-3, is actually a miRNA offset RNA (moRNA) derived from sequences located adjacent to pre-miR-rR1-3. Several other RRV-derived moRNAs were obtained, including one recovered >600 times. Together, this research provides a comprehensive list of the miRNAs and moRNAs encoded by RRV.

Characterization of the rhesus fibromatosis herpesvirus MARCH family member rfK3.

Retroperitoneal fibromatosis-associated herpesvirus (RFHV) is a gamma-herpesvirus of macaques that is closely related to Kaposi's sarcoma-associated herpesvirus (KSHV). Herein, we present characterization of the K3 gene from RFHV, a homologue of the KSHV K3 and K5 genes. Like the KSHV proteins, kK3 and kK5, the rfK3 protein decreases cell surface MHC I levels. Similar to kK5, rfK3 also modulates ICAM-1, but not another kK5 target, B7.2. Inhibitors of dynamin or mutations in the rfK3 RING-CH E3 ubiquitin ligase domain block cellular target regulation, implicating a ubiquitin-dependent, endocytosis-mediated mechanism for target down regulation and degradation. Overall, this manuscript presents the first characterization of a non-human primate virus MARCH family E3 ubiquitin ligase contributing important information about the evolution of immune avoidance strategies in primate viruses and paving the way for an animal model examining the importance of kK3 and kK5 in vivo.

Rise and fall over 26 years of a marine epizootic in Hawaiian green sea turtles.

Estimates of chronic disease prevalence are needed to improve our understanding of marine disease epizootiology, which is poorly known for marine megafauna such as marine turtles. An emerging worldwide threat to green sea turtles (Chelonia mydas) is fibropapillomatosis (FP), which is a pandemic tumor-forming disease associated with herpes-viruses. We report on a 26-yr FP epidemic in the Hawaiian Archipelago and show that apparent disease prevalence in the world's main endemic hot spot increased rapidly following a late 1980s outbreak, peaked during the mid-1990s, and then declined steadily ever since. While this disease is a major cause of sea turtle stranding in Hawaiian waters and can be fatal, we also show that long-term tumor regression can occur even for turtles with advanced FP. The endemic Hawaiian green turtle stock was severely depleted by overexploitation prior to protection under the US Endangered Species Act in 1978. This stock has increased significantly ever since, despite exposure to a major chronic disease epidemic that is currently declining.

Cutaneous and systemic poxviral disease in red (Tamiasciurus hudsonicus) and gray (Sciurus carolinensis) squirrels.

From September 2005 through October 2006, fibromatosis was diagnosed in 2 red squirrels (Tamiasciurus hudsonicus) and 1 gray squirrel (Sciurus carolinensis). All 3 squirrels had multifocal to coalescing, tan, firm alopecic cutaneous nodules. Two squirrels also had pulmonary nodules. Histologically, the cutaneous nodules had marked epidermal hyperplasia, with ballooning degeneration of keratinocytes, spongiosis, and eosinophilic cytoplasmic inclusions. The dermis was expanded by proliferation of atypical mesenchymal cells with cytoplasmic inclusions. Additional findings included pulmonary adenomatous hyperplasia with cytoplasmic inclusions, renal tubular epithelial hyperplasia with cytoplasmic inclusions, atypical mesenchymal proliferation in the liver, and atypical mesenchymal proliferation with cytoplasmic inclusions in the seminal vesicles. Ultrastructurally, poxviral particles were observed in skin scrapings and sections of cutaneous and pulmonary nodules. Polymerase chain reaction targeting the highly conserved Leporipoxvirus DNA polymerase gene was positive using DNA extracted from the cutaneous lesions of all 3 squirrels. Nucleotide sequence of the 390 base PCR amplicons was closely related to that of other members of the genus Leporipoxvirus. To the authors' knowledge, this is the first report of cutaneous and systemic poxviral disease in American red squirrels with molecular characterization of the squirrel fibroma virus.

Localization of fibropapilloma-associated turtle herpesvirus in green turtles (Chelonia mydas) by in-situ hybridization.

Fibropapilloma-associated turtle herpesvirus (FPTHV) is the presumed aetiological agent of sea turtle fibropapillomatosis (FP). Intralesional DNA and RNA of the virus have been detected by polymerase chain reaction (PCR) and reverse transcriptase-PCR (RT-PCR), respectively, but the exact location and distribution of the virus within the tumours have not been addressed. In this study, in-situ hybridization (ISH) was used to investigate viral transcriptional activity and localization of FPTHV. Twenty-five tumours were obtained from the skin or conjunctiva of 105 green turtles (Chelonia mydas) examined on two islands in Puerto Rico (Culebra and Culebrita). These lesions comprised 19 fibropapillomas and six fibromas. FPTHV mRNA transcripts were detected by ISH in three fibropapillomas, with positive reactions confined to the nuclei of clusters of epithelial cells. Viral DNA was detected by riboprobe ISH combined with denaturation in 14 tumours, including both fibropapillomas and fibromas. Signals were confined to the nuclei of acanthotic epithelial cells and were not seen in the subepithelial fibrous areas of the tumours. These results suggest that FPTHV is present in epithelial cells and transcriptionally active in fibropapillomas.

Human papillomavirus and skin tags: is there any association?

BACKGROUND: Low-risk human papillomavirus (HPV) infections are related to the genesis of various benign lesions. In an isolated report available, HPVs have been implicated in the causation of skin tags too. AIMS: The present study was designed to detect the existence of low-risk HPV types 6 and 11 in cutaneous soft fibromas (skin tag) in north Indians. METHODS: A total of 37 cases of skin tags from various sites were analyzed. Highly sensitive and comprehensive polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) assays were done for the detection of low-risk HPV types 6 and 11. RESULTS: The results revealed the presence of HPV DNA 6/11 in 48.6% of the skin tags examined by PCR-RFLP. CONCLUSION: This result corroborates the hypothesis that HPV plays a part in the etiology of benign lesions like cutaneous soft fibromas. The identification of HPV 6/11 in these lesions, which are benign proliferations of the skin, further expands the spectrum of HPV-linked lesions.

RFHVMn ORF73 is structurally related to the KSHV ORF73 latency-associated nuclear antigen (LANA) and is expressed in retroperitoneal fibromatosis (RF) tumor cells.

Retroperitoneal fibromatosis herpesvirus (RFHV), the macaque homolog of the human rhadinovirus, Kaposi's sarcoma-associated herpesvirus (KSHV), was first identified in retroperitoneal fibromatosis (RF) tumor lesions of macaques with simian AIDS. We cloned and sequenced the ORF73 latency-associated nuclear antigen (LANA) of RFHVMn from the pig-tailed macaque. RFHVMn LANA is structurally analogous to KSHV ORF73 LANA and contains an N-terminal serine-proline-rich region, a large internal glutamic acidic-rich repeat region and a conserved C-terminal domain. RFHVMn LANA reacts with monoclonal antibodies specific for a glutamic acid-proline dipeptide motif and a glutamic acid-glutamine-rich motif in the KSHV LANA repeat region. Immunohistochemical and immunofluorescence analysis revealed that RFHVMn LANA is a nuclear antigen which is highly expressed in RF spindloid tumor cells. These data suggest that RFHV LANA is an ortholog of KSHV LANA and will function similarly to maintain viral latency and play a role in tumorigenicity in macaques.

Distribution of chelonid fibropapillomatosis-associated herpesvirus variants in Florida: molecular genetic evidence for infection of turtles following recruitment to neritic developmental habitats.

Marine turtle fibropapillomatosis is associated with chelonid fibropapilloma-associated herpesvirus (C-FP-HV) and commonly affects juvenile green turtles (Chelonia mydas) in neritic (nearshore) habitats. Green turtles have a complex life history, characterized by shifts in trophic level as well as habitat during ontogeny. Thus, several hypotheses can be proposed for when turtles become infected with C-FP-HV. They may acquire the virus at an early stage in the life cycle, including prenatal, hatchling, or the posthatchling pelagic stages. Alternatively, they may become infected later in life after they emigrate from the open ocean to neritic habitats. Each hypothesis generates predictions about the spatial distribution of genetic variants of C-FP-HV among nearshore sites within a region. Sequencing of polymerase chain reaction-amplified viral DNA from fibropapillomas of individual turtles was used to genotype the viral variants present in marine turtles from different coastal areas in Florida. We found four distinct virus variants (A, B, C, and D), two of which (A and C) were present in multiple turtle species. Green turtles in Florida were infected with variants A, B, and C. Variant A was found in green turtles from all three areas. Outside the Indian River Lagoon, variant A was most commonly detected and was found in >94% of diseased green turtles and 70% of loggerhead sea turtles (Caretta caretta) in the Florida Bay/Florida Keys. However, in the Indian River Lagoon, variant B was found in >94% of affected green turtles. Variant B was not detected outside of the Indian River system. Chi-square analysis strongly supported (P<0.001) an association between viral variant distribution in green turtles and location. On the basis of the assumption that juvenile green turtles found in Florida's west-central coast, Florida Keys, and Indian River Lagoon areas represented recruits from a mixed pelagic population, we expected that the distribution of viral variants in these turtles would be relatively homogeneous among locations; this would correspond to infection in the earlier phases of their life cycle. The heterogeneous distribution of viral variants in green turtle tumors from different Florida coastal locations strongly supports the hypothesis that, during epizootics, turtles are infected with specific C-FP-HV variants after they arrive as juveniles in neritic habitats. The conclusion that C-FP-HV is acquired after turtles recruit to nearshore habitats should help focus further research efforts on understanding the mechanisms of transmission and raises the possibility that the effect of fibropapillomatosis on turtle populations might be reduced by management strategies designed to break the cycle of transmission in these locations.

Genomic variation of the fibropapilloma-associated marine turtle herpesvirus across seven geographic areas and three host species.

Fibropapillomatosis (FP) of marine turtles is an emerging neoplastic disease associated with infection by a novel turtle herpesvirus, fibropapilloma-associated turtle herpesvirus (FPTHV). This report presents 23 kb of the genome of an FPTHV infecting a Hawaiian green turtle (Chelonia mydas). By sequence homology, the open reading frames in this contig correspond to herpes simplex virus genes UL23 through UL36. The order, orientation, and homology of these putative genes indicate that FPTHV is a member of the Alphaherpesvirinae. The UL27-, UL30-, and UL34-homologous open reading frames from FPTHVs infecting nine FP-affected marine turtles from seven geographic areas and three turtle species (C. mydas, Caretta caretta, and Lepidochelys olivacea) were compared. A high degree of nucleotide sequence conservation was found among these virus variants. However, geographic variations were also found: the FPTHVs examined here form four groups, corresponding to the Atlantic Ocean, West pacific, mid-Pacific, and east Pacific. Our results indicate that FPTHV was established in marine turtle populations prior to the emergence of FP as it is currently known.

[Papilloma virus infection in pretumor and tumor masses of the larynx]. / Papillomavirusnaia infektsiia v predopukholevykh i opukholevykh obrazovaniiakh gortani.

There has been recent evidence suggesting that papilloma virus infection is of no small importance in the pathogenesis of tumors of the head and neck. This study has involved a screening of the mucosa having laryngeal pretumors and tumors for papilloma virus infection by polymerase chain reaction and immunohistochemistry. Specimens were studied in 130 patients. All the patients with laryngeal papillomatosis were found to have human papilloma virus (HPV) types 6 and 11. HPV-18 was detected in 6 (13%) of 48 cases of laryngeal cancer and in 4 (9%) of 46 cases of laryngeal mucosal precancer. Mixed HPV infection of 2-3 different types was revealed in 6 (20%) of 30 HPV-positive patients. Such a wide survey of laryngeal pretumors and tumors in the Russian population for virus infection has been conducted for the first time.

Cutaneous fibropapilloma in a mountain lion (Felis concolor).

A 12-yr-old mountain lion (Felis concolor) developed a 0.5-cm3 raised nonpigmented and nonulcerated mass between the lip and the nasal planum. The tumor was surgically removed and diagnosed histologically as a fibropapilloma. The tumor recurred 1 yr later, at which time it was again excised, and the diagnosis was reconfirmed by biopsy. Frozen tissue from the second excision was submitted for polymerase chain reaction testing for papillomavirus. The 176-base pair polymerase chain reaction product recovered from the tumor was cloned and sequenced. The papillomavirus had 96% homology with a papillomavirus previously retrieved from a fibropapilloma in a domestic cat and is the next most closely related to bovine papillomavirus type 1. This is the first report of a virus-associated fibropapilloma in a mountain lion.