ABSTRACT
Objectives A hallmark of neoplasms is their origin from a single cell; that is, clonality. Many techniques have been developed in human medicine to utilise this feature of tumours for diagnostic purposes. One approach is X chromosome-linked clonality testing using polymorphisms of genes encoded by genes on the X chromosome. The aim of this study was to determine if the feline androgen receptor gene was suitable for X chromosome-linked clonality testing. Methods The feline androgen receptor gene was characterised and used to test clonality of feline lymphomas by PCR and polyacrylamide gel electrophoresis, using archival formalin-fixed, paraffin-embedded material. Results Clonality of the feline lymphomas under study was confirmed and the gene locus was shown to represent a suitable target in clonality testing. Conclusions and relevance Because there are some pitfalls of using X chromosome-linked clonality testing, further studies are necessary to establish this technique in the cat.
Subject(s)
Cat Diseases/genetics , Genes, X-Linked , Lymphoma/veterinary , Microsatellite Repeats , Receptors, Androgen/genetics , X Chromosome/genetics , Animals , Cat Diseases/pathology , Cats , Dogs , Exons , Humans , Hyperplasia/veterinary , Lymph Nodes/pathology , Lymphoma/genetics , Lymphoma/pathology , Male , Polymerase Chain Reaction/veterinary , Polymorphism, Genetic , Sequence AlignmentABSTRACT
T-cell receptor γ alternate reading frame protein (TARP) is expressed by human prostate epithelial, prostate cancer, and mammary cancer cells, but is not found in normal mammary tissue. To date, this protein has only been described in humans. Additionally, no animal model has been established to investigate the potential merits of TARP as tumor marker or a target for adoptive tumor immunotherapy. In this study conducted to characterize feline T-cell receptor γ sequences, constructs very similar to human TARP transcripts were obtained by RACE from the spleen and prostate gland of cats. Transcription of TARP in normal, hyperplastic, and neoplastic feline mammary tissues was evaluated by conventional RT-PCR. In felines similarly to the situation reported in humans, a C-region encoding two open reading frames is spliced to a J-region gene. In contrast to humans, the feline J-region gene was found to be a pseudogene containing a deletion within its recombination signal sequence. Our findings demonstrated that the feline TARP ortholog is transcribed in the prostate gland and mammary tumors but not normal mammary tissues as is the case with human TARP.
Subject(s)
Biomarkers, Tumor/genetics , Breast Neoplasms/metabolism , Cats/genetics , Immunotherapy, Adoptive/methods , Nuclear Proteins/genetics , Animals , Base Sequence , Breast Neoplasms/genetics , DNA, Complementary/genetics , Female , Male , Molecular Sequence Data , Nucleic Acid Amplification Techniques , Open Reading Frames/genetics , Prostate/metabolism , Pseudogenes , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNAABSTRACT
A significant drop in the prevalence of feline leukaemia virus (FeLV) antigenaemic cats and antigen-associated lymphomas has been observed after the introduction of FeLV vaccination and antigen-testing with removal of persistently antigenaemic cats. However, recent reports have indicated that regressively infected cats may contain FeLV provirus DNA and that lymphoma development may be associated with the presence of provirus alone. In the present study, we investigated the presence of FeLV antigen and provirus DNA in 50 lymphomas by immunohistochemistry and semi-nested polymerase chain reaction, respectively. Interestingly, almost 80% of T-cell lymphomas and 60% of B-cell lymphomas contained provirus DNA while only 21% of T-cell lymphomas and 11% of B-cell lymphomas expressed FeLV antigen. In conclusion, our results support previous hypotheses that vaccination and removal of persistently antigenaemic cats have led to a drop in FeLV antigen-expressing lymphomas. However, FeLV provirus DNA is still present in a high percentage of feline lymphomas.
Subject(s)
Cat Diseases/virology , Leukemia Virus, Feline/genetics , Lymphoma, B-Cell/veterinary , Lymphoma, T-Cell/veterinary , Proviruses/genetics , Animals , Antigens, Viral/isolation & purification , Cats , DNA, Viral , Leukemia Virus, Feline/immunology , Lymphoma, B-Cell/virology , Lymphoma, T-Cell/virology , Polymerase Chain Reaction/methods , Polymerase Chain Reaction/veterinary , PrevalenceABSTRACT
Malignant mesotheliomas are rare tumours in domestic cats. They occur within the abdominal or thoracic cavity and are regularly associated with pleural or peritoneal effusions. The histopathological diagnosis can be quite challenging, as these neoplasms may resemble other epithelial or mesenchymal neoplasms. However, differentiation can be achieved by immunohistochemistry in most cases. Here we describe the rare case of a malignant mesothelioma of the fibrous subtype in the thoracic cavity of a cat and discuss differential diagnoses and treatment options for this tumor type.
