Search results for "Endocrine System"
showing 10 items of 1530 documents
Mutagenicity of Closely Related Carcinogenic and Noncarcinogenic Compounds Using Various Metabolizing Systems and Target Cells
1980
A total of 49 heteropolycyclic compounds belonging to structurally homogenous series was investigated for bacterial mutagenicity in the Ames test. The same batches of compounds were tested for carcinogenicity by injection into subcutaneous tissue of mice? 22 test compounds were carcinogenic, some strongly, others weakly. With the exception of one weak carcinogen, all these compounds were mutagenic. However, 15 of 27 noncarcinogens (56%) were also mutagenic. Moreover, noncarcinogenic, weakly carcinogenic, and strongly carcinogenic mutagens showed very similar mutagenic potencies.
Preservation of the soft protein corona in distinct flow allows identification of weakly bound proteins.
2018
Abstract Nanocarriers that are used for targeted drug delivery come in contact with biological liquids and subsequently proteins will adsorb to the nanocarriers’ surface to form the so called ‘protein corona’. The protein corona defines the biological identity and determines the biological response towards the nanocarriers in the body. To make nanomedicine safe and reliable it is required to get a better insight into this protein corona and, therefore, the adsorbed proteins have to be characterized. Currently, centrifugation is the common method to isolate the protein corona for further investigations. However, with this method it is only possible to investigate the strongly bound proteins,…
De novo CCND2 mutations leading to stabilization of cyclin D2 cause megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome
2014
Activating mutations in genes encoding phosphatidylinositol 3-kinase (PI3K)-AKT pathway components cause megalencephaly-polymicrogyria-polydactyly-hydrocephalus syndrome (MPPH, OMIM 603387)(1-3). Here we report that individuals with MPPH lacking upstream PI3K-AKT pathway mutations carry de novo mutations in CCND2 (encoding cyclin D2) that are clustered around a residue that can be phosphorylated by glycogen synthase kinase 313 (GSK-3 beta)(4). Mutant CCND2 was resistant to proteasomal degradation in vitro compared to wild-type CCND2. The PI3K-AKT pathway modulates GSK-3 beta activity(4), and cells from individuals with PIK3CA, PIK3R2 or AKT3 mutations showed similar CCND2 accumulation. CCND…
Differenzierung zwischen prämaturer Thelarche und Pubertas praecox anhand klinischer, hormoneller und radiologischer Befunde
2008
In a retrospective study of 39 girls (aged 10 months to 7 10/12 years) with premature breast development criteria for distinguishing between premature thelarche and precocious puberty were analysed. Serum estradiol levels and bone age were determined and a test with luteinizing hormone-releasing hormone (LHRH) performed (inclusion criteria). On the basis of the LHRH test and bone age, premature thelarche was diagnosed in 29 patients and precocious puberty in ten: while those with premature thelarche had a follicle-stimulating hormone (FSH) pattern of rise, in those with precocious puberty the rise in gonadotropin was of the LH type. The LH/FSH ratio 30 min after stimulation was 1 (median 2.…
Extracellular heat shock proteins in cancer: From early diagnosis to new therapeutic approach
2021
In cancer, human cells lose the ability to properly control the series of events that occur constantly during cell growth and division, including protein expression, stability, and dynamics. Heat shock proteins (Hsps) are key molecules in these events, constitutively expressed at high levels and could furthermore be induced by the response to cancer-induced stress. In tumor cells, Hsps have been shown to be implicated in the regulation of apoptosis, immune responses, angiogenesis and metastasis; in some cases, they can be overexpressed and dysregulated, representing important cancer hallmarks. In the past few years, it has been demonstrated that Hsps can be released by tumor cells through s…
Annexin-1 downregulation in thyroid cancer correlates to the degree of tumour differentiation
2006
We investigated the expression of annexin-1 (ANXA1) in thyroid carcinoma cell lines and in thyroid cancers with a different degree of differentiation. The highest level of ANXA1 expression examined by Western blotting was detected in the papillary carcinoma cells (NPA) and in the follicular cells (WRO). On the other hand, the most undifferentiated thyroid carcinoma cells (ARO and FRO) presented the lowest level of ANXA1 expression. In surgical tissue specimens from 32 patients with thyroid cancers, we found high immunoreactivity for ANXA1 in papillary (PTC) and follicular (FTC) thyroid cancers while in undifferentiated thyroid cancers (UTC) the expression of the protein was barely detectabl…
Type II keratin cDNAs from the rainbow trout: implications for keratin evolution.
2002
From a teleost fish, the rainbow trout Oncorhynchus mykiss, we have cloned and sequenced cDNAs encoding five different type II keratins. The corresponding protein spots, as separated by 2D-PAGE of trout cytoskeletal preparations, have been identified by peptide mass mapping using MALDI mass spectrometry. Three of the sequenced keratins are expressed in the epidermis (subtype IIe), and two in simple epithelia and mesenchymal cells (subtype IIs). The IIs keratins are both orthologs of human K8. This leaves unsequenced only the trace component S3 of the biochemically established trout keratin catalog. A phylogenetic tree has been constructed from a multiple alignment of the rod domains of the …
RASSF1A inhibits estrogen receptor alpha expression and estrogen-independent signalling: implications for breast cancer development
2012
The Ras association domain family 1 isoform A (RASSF1A) is a tumor suppressor whose inactivation is implicated in the development of many human cancers, including breast carcinomas. Little is known about the tumor-suppressive function of RASSF1A in breast tissue and whether its inactivation is mechanistically involved in the initiation and progression of breast tumors. Here, we show that RASSF1A inhibits breast cancer growth in vivo, and suppresses estrogen receptor (ERα) expression and function. Reconstitution of RASSF1A in MCF7 cells led to decreased ERα levels and reduced sensitivity to estrogen (E2). Concomitantly, we observed decreased expression of Id1 as well as the E2-responsive gen…
Different effects of interferons, interleukin‐1β and tumor necrosis factor‐α in normal (OSE) and malignant human ovarian epithelial cells
1996
Ovarian cancer arises mostly from the ovarian surface epithelium. The aim of our study was to compare the effects of cytokines in ovarian surface epithelial (OSE) cells and in ovarian carcinoma cells. Proliferation and expression of surface antigens (CA-125 and classes I and II antigens of the major histocompatibility complex [MHC]) were measured in OSE cells obtained from 7 different patients and 7 ovarian carcinoma cell lines. Proliferation of OSE cells remained unaffected by interferon (IFN)-α or IFN-γ, whereas interleukin-I (IL-I) and tumor necrosis factor (TNF) increased cell growth. Proliferation of ovarian carcinoma cells was reduced by both types of IFN as well as TNF but was not af…
Developmental Abnormalities of the Thyroid
2016
Developmental anomalies of the thyroid gland (thyroid dysgenesis) underlie the majority of cases of congenital hypothyroidism. Only a small number of monogenic defects have been shown to result in athyreosis or orthotopic thyroid hyperplasia, whereas the commonest developmental anomaly, thyroid ectopy, remains unexplained. Ectopy may result from multiple genetic or epigenetic hits in the germline and/or at the somatic level. This chapter gives a brief overview of the monogenic defects in candidate genes that have been identified so far and of the syndromes that are known to be associated with thyroid dysgenesis. In addition, we discuss gain-of-function mutations of the thyroid hormone stimu…