Dogs have been considered as an excellent immunocompetent model for human melanoma due to the same tumor location and the common clinical and pathological features with human melanoma. However, the differences in the melanoma transcriptome between the two species have not been yet fully determined. Considering the role of oncogenes in melanoma development, in this study, we first characterized the transcriptome in canine oral melanoma and then compared the transcriptome with that of human melanoma. The global transcriptome from 8 canine oral melanoma samples and 3 healthy oral tissues were compared by RNA‑Seq followed by RT‑qPCR validation. The results revealed 2,555 annotated differentially expressed genes, as well as 364 novel differentially expressed genes. Dog chromosomes 1 and 9 were enriched with downregulated and upregulated genes, respectively. Along with 10 significant transcription site binding motifs; the NF‑κB and ATF1 binding motifs were the most significant and 4 significant unknown motifs were indentified among the upregulated differentially expressed genes. Moreover, it was found that canine oral melanoma shared >80% significant oncogenes (upregulated genes) with human melanoma, and JAK‑STAT was the most common significant pathway between the species. The results identified a 429 gene signature in melanoma, which was up‑regulated in both species; these genes may be good candidates for therapeutic development. Furthermore, this study demonstrates that as regards oncogene expression, human melanoma contains an oncogene group that bears similarities with dog oral melanoma, which supports the use of dogs as a model for the development of novel therapeutics and experimental trials before human application.

The complete nucleotide sequence of the avian leukosis virus causing so-called fowl glioma has been previously determined. Primers were designed for detection of the fowl glioma-causal virus (FGV) based on the 3′ untranslated region of the viral genome. The provirus and viral RNA of FGV were specifically detected in various organs and tissues, including feather pulp, from experimentally infected birds using nested polymerase chain reaction (PCR) and reverse transcription nested PCR. The prevalence of FGV was evaluated in 131 Japanese fowls of a zoological garden in Japan based on the detection of the FGV genome in feather pulp using PCR and the detection of viral antigen in faeces by enzyme-linked immunosorbent assay. FGV proviral DNA was detected in feather pulp of 52 birds (39.7%) by nested PCR. Later, nine dead birds from among the 52 were histologically diagnosed as having fowl glioma and found to have the proviral DNA in the affected brain. These results demonstrated that the PCR-based detection of FGV in feather pulp is useful for epidemiological studies on fowl glioma. Réaction de polymérisation en chaîne nichée pour la détection du virus de la leucose responsable du gliome des poules La séquence nucléotidique complète du virus de la leucose aviaire responsable du gliome des poules a été précédemment déterminée. Des amorces ont été choisies pour la détection du virus responsable du gliome des poules (FGV), basées sur la région 3′ non traduite (UTR) du génome viral. Le provirus et l'ARN viral du FGV ont été détectés spécifiquement dans différents organes et tissus, incluant la pulpe de plume, à partir d'animaux infectés expérimentalement, en utilisant respectivement la réaction de polymérisation en chaîne (PCR) nichée ou une transcription inverse (RT) suivie d'une PCR nichée. La prévalence du FGV a été évaluée à partir de 131 poules japonaises d'un jardin zoologique au Japon par détection du génome du FGV dans la pulpe de plume utilisant la PCR et par détection de l'antigène viral dans les fèces par ELISA. L'ADN proviral du FGV a été détecté dans la pulpe de plume chez 52 sujets (39.7%) par PCR nichée. Par la suite, 9 sujets sur les 52 étudiés sont morts. Ils ont fait l'objet d'un examen histologique qui a montré la présence de gliome, de plus l'ADN proviral a été mis en évidence dans le cerveau affecté. Ces résultats ont montré que la détection par PCR du FGV dans la pulpe de plume est utile pour les études épidémiologiques du gliome des poules. Nested Polymerasekettenreaktion zum Nachweis von das sogenannte Geflügelgliom verursachendem aviären Leukosevirus Die komplette Nukleotidsequenz des aviären Leukosevirus, das das sogenannte Geflügelgliom induziert, ist kürzlich ermittelt worden. Basierend auf der untranslatierten Region (UTR) des viralen Genoms wurden Primer entwickelt für den Nachweis des Gefügelgliom verursachenden Virus (FGV). Das Provirus und virale RNS des FGV wurden spezifisch unter Verwendung von nested Polymerasekettenreaktion (PCR) und Reverse Transkriptase (RT) nested PCR in verschiedenen Organen und Geweben, einschließlich Federfollikeln, experimentell infizierter Tiere nachgewiesen. Das Vorkommen von FGV wurde bei 131 japanischen galliformen Vögeln in einem Zoo in Japan durch den Nachweis von FGV-Genom in Federfollikeln mittels PCR und von viralem Antigen in Fäzes anhand eines Enzymimmunotests überprüft. Provirale FGV-DNS wurde mit der nested PCR in den Federfollikeln von 52 (39,7%) Vögeln festgestellt. Später wurde bei 9 toten Vögeln von diesen 52 Vögeln histologisch Geflügelgliome diagnostiziert und in den betroffenen Gehirnen provirale DNS nachgewiesen. Diese Ergebnisse zeigen, dass der PCR basierte Nachweis von FGV in Federfollikeln für epidemiologische Studien zur Verbreitung von Geflügelgliomen geeignet ist. Reacción en cadena de la polimerasa anidada para detectar el virus de leucosis aviar que causa el llamado glioma aviar La secuencia completa del virus de leucosis aviar que causa el llamado glioma aviar ya ha sido determinado previamente. Se diseñaron cebadores para detectar el virus causante del glioma aviar (FGV) en base a la región no codificante (UTR) 3′ del genoma vírico. El provirus y el ARN vírico del FGV se detectaron específicamente en varios órganos y tejidos, incluida la pulpa de pluma, de aves infectadas experimentalmente mediante una técnica anidada de reacción en cadena de la polimerasa (PCR) y transcriptasa reversa (RT) PCR anidada. La prevalencia de FGV fue evaluada en 131 aves japonesas de un parque zoológico en Japón en base a la detección del genoma de FGV en pulpa de pluma utilizando la PCR y a la detección del antígeno vírico en heces mediante ELISA. El ADN del provirus de FGV se detectó en la pulpa de la pluma de 52 (39.7%) aves mediante PCR anidada. Posteriormente, a 9 aves muertas de un total de 52 se les diagnosticó histológicamente un glioma aviar y se le detectó ADN proviral en el cerebro afectado. Estos resultados demuestran que la PCR basada en la detección de FGV en pulpa de pluma es útil en los estudios epidemiológicos de glioma aviar.

Fowl glioma-inducing virus (FGV), which belongs to subgroup A of avian leukosis virus (ALV), is tumorigenic in the nervous system. In a zoological garden in Japan, approximately 40% of chickens, including Japanese fowls, were infected with FGV. Because this zoological garden plays a role as a major supplier of Japanese fowl for other zoological gardens, FGV infection is suspected to have spread among ornamental chickens. In this study, the prevalence of the disease was examined in a total of 129 chickens in three other zoological gardens by nested polymerase chain reaction (PCR), reverse transcription nested PCR and enzyme-linked immunosorbent assay. Twenty-six to 56 percent of the fowls in each of the examined gardens were positive by nested PCR. The phylogenetic analysis revealed that the 3' untranslated region, including the specific sequence of FGV, of the 14 isolated ALVs showed high sequence identity and a close relationship with FGV. In addition, the env gene of the isolates frequently showed mutations and deletions of nucleotides. These results suggest that FGV is prevalent among ornamental chickens kept in zoological gardens in Japan.

Fowl glioma is characterized by multiple nodular growth of astrocytes, and fowl glioma-inducing virus belonging to avian leukosis virus has been isolated from Japanese bantam as a causal agent. Subcutaneous neoplasms of the head and neck have been reported in layer chickens since 2003 in Japan, and fowl glioma concurred in these affected layers. In the present study, the histopathology of 240 layers, including 18 layers with subcutaneous neoplasms and 222 layers kept with the affected layers, was performed to clarify the characteristics of fowl glioma in layers. Microscopically, 103 layers showed non-suppurative encephalitis, and four layers had locally extensive proliferation or multiple nodules of astrocytes. Gliomas concurred in 11 layers with subcutaneous neoplasms and occurred independently in three layers. In addition, two layers had locally extensive proliferation of small, round cells in the cerebrum. The fowl glioma-inducing virus genome was not detected in the affected brains by nested polymerase chain reaction. Ten isolates were obtained from the affected brains. By nucleotide sequencing of the env gene, SU coding regions of these isolates were most closely related to myeloblastosis-associated virus-like viruses, but TM regions showed the highest similarity to endogenous viral (ev) loci. The genome of one isolate mainly consisted of ev loci and contained several parts of other avian leukosis/sarcoma viruses. These results show that the causal avian leukosis virus of fowl glioma is not just fowl glioma-inducing virus and that different avian leukosis virus strains having oncogenicity in the central nervous system by recombination are spread in layers in Japan.