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Dec 2019 DOI 10.14302/issn.2575-1212.jvhc-19-3101
Papillary carcinoma is a mammary neoplasia of women and female dogs characterized by papillary fibrovascular projections lined by epithelial cells. Evaluation on the biology of these tumors can be done by immunohistochemistry through detection of alpha-smooth muscle actin protein in the papillary myoepithelium, which lacks such a molecule during malignant proliferations. Thus, this study aimed at determining the malignancy degree of papillary mammary tumors of female dogs by immunohistochemistry. Twenty samples of mammary neoplastic tissues collected from female dogs treated in the Veterinary Hospital at FCAV were evaluated by Hematoxylin and Eosin staining (H&E) and tumor cells were immunolabelled with monoclonal antibody to alpha-smooth muscle actin (α-SMA). Five out of 20 cases showed positive immunolabeling greater than 10% of the total immunolabeling. The remaining fourteen cases presented immunostaining lesser than 10% showing decrease or absence of α-SMA labeling in the myoepithelium of the papilla tumors. All those cases in which immunostained cell was over 10% of the neoplasm (5 immunostains of 20 total cases) were classified as benign whereas those below 10% of immunostained in the slid were considered as malignant. Therefore, immunohistochemistry played an essential role in differentiating benign and malignant papillary tumors of bitches as already described for female. Tumor classification by conventional methods, such as H&E staining, can lead to erroneous interpretations on the real biological behavior of the papillary mammary tumor.
Jul 2017 DOI 10.14302/issn.2575-1212.jvhc-17-1586
The mammary tumor is one of the most common cancer in female dogs and, at the present days, there is a big focus on the study of the relation between this kind of tumor in animals and the cells that stay around them, like the inflammatory cells. The objective of this study was to evaluate and show where the inflammatory cells stay in simple mammary carcinomas in female dogs by immunohistochemistry. Samples of simple mammary carcinomas (tumor group; n=26) and mammary gland samples without tumor (control group; n=18) were submitted to immunohistochemical analysis for the detection of T lymphocytes, macrophages, plasma cells and the MHC-II molecule. The mast cells were evaluated by the histochemical technique (toluidine blue). Lymphocytes, macrophages and mast cells were observed distributed in the tumor stroma. MHC-II was detected in tumor cells and in the inflammatory infiltrate. Plasma cells predominated in the peritumoral stroma. Macrophages differed significantly between the two groups and predominated in the tumor group. In the comparison between histological types of mammary carcinomas, mast cells differed significantly between solid tumors of the tubular / papillary types. The cytoplasmic immunodetection of MHC-II was suggested an inefficient antigen presentation. Some of the leukocytes present in the tumor infiltrate, appear to be exerting a pro-tumor effect and allowing the progression of tubular and papillary carcinomas. But in solid carcinomas (may be poorly immunogenic), as they had the lowest proportion of leukocytes present in the tumor site. More studies are necessary to confirm these results, such as the determination of the cytokine profile and the predominant leukocyte subpopulations in the tumor microenvironment.
Jan 2013 DOI 10.14302/issn.2329-9487.jhc-12-102
Background: Heart valves share developmental signaling pathways with cartilage and bone. While calcific aortic valve disease (CAVD) has been associated with valve calcification and stenosis, suggestive of osteogenesis, myxomatous mitral valve disease (MMVD) is characterized by net matrix degradation, exuberant deposition of proteoglycan, and valve regurgitation. Methods: We determined the presence of cartilage-abundant proteoglycan, aggrecan; cartilage-specific type II collagen; chondrogenic transcription factor, Sox9; and osteogenic transcription factor, Runx2 in human normal and myxomatous mitral valve leaflets by immunohistochemistry. Results and Conclusions: Myxomatous, but not normal, mitral valves demonstrated sharp focal areas that were abundant in aggrecan, type II collagen, and Sox9. These focal areas co-localized with areas of myxomatous pathologic change on Movat staining. Some cells in these areas had a round and hypertrophic morphology reminiscent of chondrocytes. Runx2 was only weakly present in normal and myxomatous mitral valves. These findings suggest a focal pathologic process in MMVD that mimics chondrogenesis.