Expression of keratins, epidermal proteins and inflammatory cells in superficial pemphigus dogs

Superficial pemphigus in dogs is an autoimmune skin disorder. The disease is characterised by the binding of auto-antibodies to desmosomal molecules including desmocollin-1, a major auto-antigen in dogs. However, data on the expression of epidermal proteins in dogs are still limited. Therefore, the aim of this study was to investigate the keratins and epidermal proteins in dogs with superficial pemphigus using immunohistochemistry. Skin biopsies were performed on dogs with pemphigus foliaceus (n=10), pan-epidermal pustular pemphigus (n=4) and pemphigus erythematosus (n=1). Immunostaining for keratin 5 and keratin 10 showed a premature and discontinuous pattern in the suprabasal layers of all pemphigus skin samples compared to the control group (P<0.05). Filaggrin, desmocollin-1 and claudin-1, but not involucrin, were significantly reduced (P<0.05). Inflammatory cells markedly infiltrated in the dermis and the lower epidermis of all pemphigus skins. This is the first report that associates changes in the expression of keratin 5, keratin 10, filaggrin and claudin-1 with reduced desmocollin-1 expression and subsequent loss of the epidermal barrier in superficial pemphigus

Proto-oncogene HER-2 in normal, dysplastic and tumorous feline mammary glands: an immunohistochemical and chromogenic in situ hybridization study

<p>Abstract</p> <p>Background</p> <p>Feline mammary carcinoma has been proposed as a natural model of highly aggressive, hormone-independent human breast cancer. To further explore the utility of the model by adding new similarities between the two diseases, we have analyzed the oncogene HER-2 status at both the protein and the gene levels.</p> <p>Methods</p> <p>Formalin-fixed, paraffin-embedded tissue samples from 30 invasive carcinomas, 7 benign lesions and two normal mammary glands were analyzed. Tumour features with prognostic value were recorded. The expression of protein HER-2 was analyzed by immunohistochemistry and the number of gene copies by means of DNA chromogenic <it>in situ </it>hybridization.</p> <p>Results</p> <p>Immunohistochemical HER-2 protein overexpression was found in 40% of feline mammary carcinomas, a percentage higher to that observed in human breast carcinoma. As in women, feline tumours with HER-2 protein overexpression had pathological features of high malignancy. However, amplification of HER-2 was detected in 16% of carcinomas with protein overexpression, a percentage much lower than that observed in their human counterpart.</p> <p>Conclusion</p> <p>Feline mammary carcinoma would be a suitable natural model of that subset of human breast carcinomas with HER-2 protein overexpression without gene amplification.</p

The Relevance of CD117-Immunocytochemistry Staining Patterns to Mutational Exon-11 in c-kit Detected by PCR from Fine-Needle Aspirated Canine Mast Cell Tumor Cells

Canine cutaneous mast cell tumors (MCT) are the lethal skin tumors. The biological behavior of the MCT cells is quite varied and unpredictable. Almost MCT dogs usually require a rapid diagnosis and therapy. However, MCT diagnosis and prognosis are still dependent on histopathology which is rather inconvenient, time-consuming, painful, and harmful for some cases. Indeed, MCT can be easily accessible using fine-needle aspiration (FNA). In this study, our biopsy specimens were classified as low- and high-grade MCT based on the novel 2-tier histopathologic grading system. We have demonstrated the usage of fine-needle aspirated MCT cells (FNA-MCT cells) from these specimens as a primary cell source to study the distribution of CD117-immunocytochemistry (CD117-ICC) staining patterns and the frequency of internal tandem duplication- (ITD-) mutant exon-11 of c-kit. The result has substantially shown that there were three staining patterns identified in the cells. Only paranuclear pattern was significantly increased in the cells from high-grade MCT. Altogether, the ITD-mutant exon-11 was also detectable only in these cells. Therefore, the result has supported our hypothesis that there was an increased opportunity to observe a higher CD117-ICC staining pattern and exon-11 mutation in high-grade MCT; even these two parameters may not precisely indicate a histopathological grade