Jung-Youn Han

Helicobacter pylori promotes hepatic fibrosis in the animal model

Helicobacter pylori infection has been reported to be very common in patients with chronic liver diseases, including cirrhosis. To elucidate the pathological effect of H. pylori infection on the progression of hepatic fibrosis, C57BL/6 mice and Sprague–Dawley rats were orally inoculated with H. pylori, and hepatic fibrosis was induced with carbon tetrachloride (CCl4) administration. We observed the histopathological changes and the presence of H. pylori genes by PCR in the liver. Significant increase in the fibrotic score as well as in serum alanine aminotransferase and aspartate aminotransferase levels was shown in the CCl4+H. pylori group compared with that in the CCl4-treated group. Compared with the CCl4-treated group, α-smooth muscle actin and transforming growth factor-β1 were enhanced; however, senescence marker protein-30, a multifunctional protein protecting hepatocytes against oxidative stress and apoptosis, was suppressed in the CCl4+H. pylori group. The 16S rRNA (400 bp) was demonstrated by PCR for H. pylori genes from genomic DNA extracted from the liver, and H. pylori-infected mice showed 93.8% (15 of 16) seropositivity by contrast with seronegativity in all H. pylori-noninfected mice. In addition, immunohistochemical study against H. pylori showed positive antigen fragments in the liver of the infected groups. Consequently, our data suggest that H. pylori infection could be an important contributing infectious factor to the development of liver cirrhosis.

Immunohistochemistry Diagnosis of an Ovarian Dysgerminoma in One Bitch

An ovarian enlargement (diameter, 8 cm) was identified and surgically excised from a 5-year-old female dog. Microscopic examination of the multinodular neoplasm revealed sheets of polygonal neoplastic cells with large nuclei, frequent mitosis, necrosis and haemorrhage. Immunohistochemically, the neoplastic cells were positive for vimentin and alkaline phosphatase but were negative for CD3, CD79a, cytokeratin, alpha-fetoprotein, inhibin-alpha and S-100. The histopathological diagnosis of the mass was unilateral ovarian dysgerminoma.

Subcutaneous leiomyosarcoma in an adrenomedullin heterozygous mouse

The present study reports a case of a 5-month-old female adrenomedullin (AM) heterozygous (+/-) mouse that presented a mass of leiomyosarcoma found in the right shoulder girdle region. The neoplastic mass extended to the sternal region and showed hemorrhages, congestion and necrotic foci. The excised tumor with a diameter of 2.5cm was firm, ill-demarcated and had focally infiltrated the surrounding muscles. The cut surface was homogeneously whitish with multi-focal reddish lesions. Microscopically, the tumor composed of variable fascicles of spindle-shaped cells with pleomorphic and cigar-shaped nuclei. The nuclei were round and elongated. Metastasis of tumor cell to skeletal muscle was frequently observed. Immunohistochemically, desmin, vimentin and alpha-smooth muscle actin (alpha-SMA) were demonstrated in neoplastic cells but tumor cells were negative for cytokeratin (CK) and S-100. Based on gross finding, microscopical examination and immunohistochemistry, the present case was diagnosed as a subcutaneous leiomyosarcoma.

Mixed Osteosarcoma with Metastatic Alveolar Carcinomatous Appearance in Canine Mammary Gland Tumor

We describe here a case of malignant mixed osteogenic tumor of the mammary gland with alveolar carcinomatous appreance. A firm, 2 to 2.5cm (in diameter) mass under the 5th nipple, showing the structure of extraosseous osteogenic sarcoma, was removed from the left 5th mammary gland of 12-year-old female dog. When investigated under the microscope, the osteoid material undergoing mineralization was surrounded by numerous scattered osteoblasts and a few osteoclastic cells throughout the osteoid tumorous stroma. The osteoid lesions were continuous with hypercellular myoepithelial cells of a very immature character with several mitotic figures. In addition, there were also carcinomatous tubules and alveoli, with invading cells into peripheral stroma, surrounded by myoepithelial cells in the mammary gland. In these lesions, emanating cords of tumor cells appear to be continuous with the myoepithelial cell layer of a duct. The presence of all these cell types suggests the existence of a common malignant origin, the stem cell being differentiated into epithelial carcinomatous and mesenchymal sarcomatous chondral and osteogenic tissues.

HER-2/neu Protein Expression in Canine Mammary Adenocarcinoma

In this study to evaluate the involvement of EGFR, HER-2/neu and ALCAM (CD166) oncogene products in canine mammary neoplastic lesions, sections of archived paraffin-embedded samples of 49 mammary tumors were analyzed immunohistochemically using antibodies against human EGFR and HER-2/neu and ALCAM. These 49 tumors were divided into 2 groups: 22 benign (19 adenoma, 3 benign mixed tumors) and 27 malignant tumors (2 simple adenocarcinomas, 5 complex adenocarcinomas, 3 solid carcinoma, 5 sclerosing carcinoma, 8 malignant mixed tumors and 4 malignant myoepithelioma). As a result of immunostaining, 31.8% (7/22) of the benign tumors and 29.6% (8/27) of the malignant tumors expressed the HER-2/neu oncogene product, EGFR expression was detected in 27.3% (6/22) of benign tumors and in 22.2% (6/27) of the malignant tumors. ALCAM expression was detected in 40.9% (9/22) of benign tumors and in 7.4% (2/27) of the malignant tumors. These results suggest that some of the biological and morphological characteristics of the tumor are associated with canine mammary gland tumors, as also reported for human breast cancer, the possibility of using anti-HER-2/neu antibodies in the treatment of canine mammary tumors.

Perianal Adenocarcinoma in Dog

A 12.6-year-old, male Shitzu was diagnosed with perianal adenocarcinoma. The presented mass was brown to black, 4×3×3 cm in size, and yellowish on cut section. Microscopic findings revealed that the mass composed of variable sized clusters of hepatoid cells with inconspicuous distinct. The tumor cells were polyhedral and pyknotic and exhibited high mitotic activity. Tumor cells intermingled with basaloid cells and primitive cells invaded the adjacent normal tissues. Basaloid cells exhibited positive immunoreactivity for Epidermal growth factor receptor (EGFR), human epidermal growth factor receptor (HER-2/neu), matrix metallopnateinase 9 (MMP-9), and perianal adenocarcinoma, protein kinase C alpha (PKC α). Generally, tumors of the perianal gland are common and benign 4.5 times more often than carcinoma in the dog, particularly in males. In the present report, we examined histopathological and immunohistochemical characteristics of a rare perianal adenocarcinoma in association with proteins involved tumor metastasis and adenocarcinoma development.