Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.15.1 (ACE)
 18,300 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Primary mediastinal seminoma is a rare germ cell tumor that is histologically identical to testicular seminoma. Fifty-one cases have been reported in the Japanese literature. This report concerns a new case of this tumor which showed high levels of a serum alkaline phosphatase (ALP) and a serum angiotensin converting enzyme (ACE). The patient is a 27 year old man whose father underwent an orchiectomy with postoperative radiation therapy for testicular tumor. After radiation and chemotherapy, the patient's chest X-ray showed complete regression of the mass, and his ALP and ACE decreased to normal levels.
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PMID:[Primary mediastinal seminoma--a case report]. 328 91

Angiotensin I-converting enzyme (ACE, CD143, Kininase II, EC 3.4.15.1) occurs in two isoforms; whereas the somatic isoform (sACE) appears in certain endothelial cells and some other cell types, the testicular isoform (tACE) was found in humans and various mammals only during spermiogenesis. An expression of ACE was reported formerly in some human seminomas, but its isoform type, cellular distribution, and pathogenetic meaning are not known. Therefore we analyzed normal human testes, 22 different testicular tumors, and 23 fetal and postnatal tissues of different stages of testicular development. By reverse transcriptase-polymerase chain reaction, ACE mRNA isoforms were assessed in homogenized tissue sections and in germ cells selectively isolated by laser-assisted cell picking. Immunohistochemistry was performed on consecutive sections using monoclonal antibodies specific to the human somatic isoform or both, sACE and tACE. In adult men, tACE was detectable in spermatids and spermatozoa, but normal spermatogonia and spermatocytes were not found to express ACE in any isoform. By contrast, both mRNA and protein of sACE were detectable in the cells of intratubular germ cell neoplasm, seminomas, and other testicular tumor types. Because sACE was also found in fetal germ cells, our findings point to profound differences in the regulation of ACE expression in fetal, mature adult, and neoplastic germ cells. They are in agreement with the concept that neoplastic germ cells phenotypically reflect an embryonic stage of cellular differentiation. Laser-assisted cell picking proved to be a reliable method to investigate differently regulated mRNA of cells which reside in close neighborhood within complex tissues.
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PMID:Angiotensin-converting enzyme (CD143) in neoplastic germ cells. 1057 13

The angiotensin I-converting enzyme (ACE, kininase II, CD143) shows a broad specificity for various oligopeptides. Besides the well-known conversion of angiotensin I to II, ACE degrades efficiently kinins and the tetrapeptide AcSDKP (goralatide) and thus equally participates in the renin-angiotensin system, the kallikrein-kinin system, and the regulation of stem cell proliferation. In the mammalian testis, ACE occurs in two isoforms. The testicular isoform (tACE) is exclusively expressed during spermatogenesis and is generally thought to represent the germ cell-specific isozyme. However, we have previously demonstrated that, in addition to tACE, the somatic isoform (sACE) is also present in human germ cells. Similar to other oncofoetal markers, sACE exhibits a transient expression during foetal germ cell development and appears to be a constant feature of intratubular germ cell neoplasm, the so-called carcinoma-in-situ (CIS) and, in particular, of classic seminoma. This demands the existence of specific paracrine functions during male germ cell differentiation and development of male germ cell tumours, which are mediated by either of the two ACE isoforms. Considering the complexity of current data about ACE, a logical connection is required between (I) the precise localisation of ACE isoforms, (I) the local access to potential substrates and (II) functional data obtained by knockout mice models. The present article summarises the current knowledge about ACE and its potential substrates with special emphasis on the differentiation-restricted ACE expression during human spermatogenesis and prespermatogenesis, the latter being closely linked to the pathogenesis of human germ cell tumours.
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PMID:Angiotensin I-converting enzyme and potential substrates in human testis and testicular tumours. 1275 69

Etiologies of a thickened stalk include inflammatory, neoplastic, and idiopathic origins, and the underlying diagnosis may remain occult. We report a patient with a thickened pituitary stalk (TPS) and papillary thyroid carcinoma (PTC) whose diagnosis remained obscure until a skin lesion appeared. The patient presented with PTC, status postthyroidectomy, and I(131) therapy. PTC molecular testing revealed BRAF mutant (V600E, GTC>GAG). She had a 5-year history of polyuria/polydipsia. Overnight dehydration study confirmed diabetes insipidus (DI). MRI revealed TPS with loss of the posterior pituitary bright spot. Evaluation showed hypogonadotropic hypogonadism and low IGF-1. Chest X-ray and ACE levels were normal. Radiographs to evaluate for extrapituitary sites of Langerhans Cell Histiocytosis (LCH) were unremarkable. Germinoma studies were negative: normal serum and CSF beta-hCG, alpha-fetoprotein, and CEA. Three years later, the patient developed vulvar labial lesions followed by inguinal region skin lesions, biopsy of which revealed LCH. Reanalysis of thyroid pathology was consistent with concurrent LCH, PTC, and Hashimoto's thyroiditis within the thyroid. This case illustrates that one must be vigilant for extrapituitary manifestations of systemic diseases to diagnose the etiology of TPS. An activating mutation of the protooncogene BRAF is a potential unifying etiology of both PTC and LCH.
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PMID:Occult Langerhans Cell Histiocytosis Presenting with Papillary Thyroid Carcinoma, a Thickened Pituitary Stalk and Diabetes Insipidus. 2765 1