Biomedical subjects

Tsukasa Inoue

Publications and source records attributed to Tsukasa Inoue.

5 recordsLinked to original sources

PubMed2005

3beta-Hydroxysteroid dehydrogenase in human aorta.

3beta-Hydroxysteroid dehydrogenase (3beta-HSD) is known to be involved in steroid production and/or metabolism and to be expressed in many tissues including adrenal cortex. Expression of this enzyme has also been elucidated in human cardiovascular system but its details remain largely unknown. Therefore, in this study, we examined the status of 3beta-HSD in postmortem human aorta utilizing RT-PCR and immunohistochemical analysis. Both mRNAs and immunoreactivity for the enzyme were detected predominantly in female aorta, and in those with mild atherosclerotic changes. In addition, immunohistochemical study demonstrated that immunoreactivity for 3beta-HSD was detected in vascular smooth muscle cells (VSMCs) of aorta. These findings all indicated that steroidogenesis via 3beta-HSD may occur in VSMCs of human aorta, possibly related to gender differences and/or the degree of atherosclerosis.

3-Hydroxysteroid Dehydrogenases↗

PubMed2005

Progesterone receptor subtypes in vascular smooth muscle cells of human aorta.

Progesterone is involved in various functions of the cardiovascular system, including those of vascular smooth muscle cells (VSMCs) via progesterone receptor (PR). Progesterone has also been postulated to be involved in inhibition of VSMC proliferation via PR. However, the details of PR expression have remained largely unknown in human cardiovascular VSMCs. Therefore, we first examined the relative levels of PR isoform (PR-A and PR-B) expression in VSMCs, using both immunohistochemistry and quantitative RT-PCR analysis. PR-B was equally expressed between male and female aorta, but PR-A was more abundant in female than in male aorta. This finding demonstrated that the status of PR subtype expression was associated with the difference of genders.

Adult↗

PubMed2004

Immunohistopathological and molecular genetic features of a case in which gastrointestinal stromal tumor recurred five times.

Gastrointestinal stromal tumor (GIST) is a distinct group of mesenchymal neoplasms recently shown to exhibit differentiation toward interstitial cells of Cajal. Although previous studies have shown that the clinical outcome of patients with GIST is associated with mitotic activity, the proliferation index determined by the Ki-67 labeling index, immunophenotype (CD34 and/or p53) and mutation in exon 11 of the c-kit, a definitive discrimination between benign and malignant GIST has not yet been established. We report a patient in whom malignant GIST in the abdomen recurred five times. In this case, the primary GIST and the five recurrent GIST were associated with c-kit immunoreactivity, but the mitotic index of the GIST tended to be increasingly higher with subsequent recurrences. Mutational analysis of the c-kit revealed that the primary and recurrent GIST were mutant-negative. These data indicated that 'morphologically appearing benign' tumors with lower proliferative parameters may also have the capacity of metastasis and recurrence.

Biomarkers, Tumor↗

PubMed2002

Progesterone production and actions in the human central nervous system and neurogenic tumors.

Progesterone has been suggested to be involved in the functions of the nervous system, but it has yet to be examined in humans. Progesterone has also been postulated to be involved in the biological behavior of various human neurogenic tumors via progesterone receptors A and B (PR-A and PR-B). In this study we examined the expression of PR and the enzymes responsible for progesterone biosynthesis (P450scc, 3betahydroxysteroid dehydrogenase, and steroidogenic acute regulatory protein) in human brain. We also examined the distribution of PR isoforms in neurogenic tumors using immunohistochemistry and RT-PCR analysis. The presence of PR and mRNA for P450scc, 3beta-hydroxysteroid dehydrogenase, and steroidogenic acute regulatory protein was detected in human brain. PR isoforms were detected in neurogenic tumors. PR-A and PR-B were equally expressed in meningiomas, but PR-B was the predominant isoform compared with PR-A in astrocytic tumors and Schwannomas. There was a statistically significant inverse correlation between PR-A and the proliferation index in meningiomas and astrocytic tumors. These findings suggest that progesterone is locally synthesized and exerts its actions through PR in the human central nervous system, and that progesterone may be involved in regulation of the growth and development of neurogenic tumors via PR, especially in the inhibition of tumor cell proliferation via PR-A.

3-Hydroxysteroid Dehydrogenases↗

PubMedDate not supplied

Giant hepatic metastasis from gastrointestinal stromal tumor of the rectum 12 years after surgery.

Gastrointestinal stromal tumors are non-epithelial neoplasms that arise from the gastrointestinal tract. Their variable cytologic atypia makes it difficult to predict their prognosis. We report a case of right hepatectomy for a giant metastasis detected 12 years after the surgical treatment of a rectal neoplasm, histologically demonstrated as a low-grade leiomyosarcoma initially, having morphological and immunohistochemical features of low malignancy. Histological examination of the hepatic metastases demonstrated that the tumors were composed of spindle cells similar to those in the rectal neoplasm. Immunohistochemical staining of the hepatic metastases with Ki-67 revealed stronger than the primary tumor. In conclusion, although histological and immunohistochemical analyses provide useful prognostic information, the prognosis of gastrointestinal stromal tumors is difficult to predict. Therefore, a patient with gastrointestinal stromal tumor diagnosed as low-grade malignancy requires carefully long-term follow-up.

Hepatectomy↗