The Daily Expression of ABCC4 at the BCSFB Affects the Transport of Its Substrate Methotrexate.

The choroid plexuses (CPs), located in the brain ventricles, form an interface between the blood and the cerebrospinal fluid named the blood-cerebrospinal barrier, which, by the presence of tight junctions, detoxification enzymes, and membrane transporters, limits the traffic of molecules into the central nervous system. It has already been shown that sex hormones regulate several CP functions, including the oscillations of its clock genes. However, it is less explored how the circadian rhythm regulates CP functions.

Promoter Demethylation Upregulates Gene Expression in Human Prostate Cancer: In Vitro and In Silico Analysis.

The Six Transmembrane Epithelial Antigen of the Prostate () is an oncogene overexpressed in several human tumors, particularly in prostate cancer (PCa). However, the mechanisms involved in its overexpression remain unknown. It is well known that epigenetic modifications may result in abnormal gene expression patterns, contributing to tumor initiation and progression.

Correction: Transthyretin expression in the postischemic brain.

[This corrects the article DOI: 10.1371/journal.pone.

Triiodothyronine modulates neuronal plasticity mechanisms to enhance functional outcome after stroke.

The development of new therapeutic approaches for stroke patients requires a detailed understanding of the mechanisms that enhance recovery of lost neurological functions. The efficacy to enhance homeostatic mechanisms during the first weeks after stroke will influence functional outcome. Thyroid hormones (TH) are essential regulators of neuronal plasticity, however, their role in recovery related mechanisms of neuronal plasticity after stroke remains unknown.

Knockdown of STEAP1 inhibits cell growth and induces apoptosis in LNCaP prostate cancer cells counteracting the effect of androgens.

Six transmembrane epithelial antigen of the prostate 1 (STEAP1) is overexpressed in numerous types of tumors, especially in prostate cancer. STEAP1 is located in the plasma membrane of epithelial cells and may play an important role in inter- and intracellular communication. Several studies suggest STEAP1 as a potential biomarker and an immunotherapeutic target for prostate cancer.

The choroid plexus as a sex hormone target: Functional implications.

The choroid plexuses (CPs) are highly vascularized branched structures that protrude into the ventricles of the brain, and form a unique interface between the blood and the cerebrospinal fluid (CSF). In recent years, novel functions have been attributed to this tissue such as in immune and chemical surveillance of the central nervous system, brain development, adult neurogenesis and circadian rhythm regulation. Sex hormones (SH) are widely recognized as modulators in several neurodegenerative diseases, and there is evidence that estrogens and androgens regulate several fundamental biological functions in the CPs.

'Smelling' the cerebrospinal fluid: olfactory signaling molecules are expressed in and mediate chemosensory signaling from the choroid plexus.

The olfactory-type signaling machinery has been known to be involved not only in odorant detection but also in other tissues with unsuspected sensory roles. As a barrier, the choroid plexus (CP) is an active participant in the monitoring of the cerebrospinal fluid (CSF), promptly responding to alterations in its composition. We hypothesized that olfactory signaling could be active in CP, contributing to the surveillance of the CSF composition.

Histopathological and in vivo evidence of regucalcin as a protective molecule in mammary gland carcinogenesis.

Regucalcin (RGN) is a calcium-binding protein, which has been shown to be underexpressed in cancer cases. This study aimed to determine the association of RGN expression with clinicopathological parameters of human breast cancer. In addition, the role of RGN in malignancy of mammary gland using transgenic rats overexpressing the protein (Tg-RGN) was investigated.

Expression of STEAP1 and STEAP1B in prostate cell lines, and the putative regulation of STEAP1 by post-transcriptional and post-translational mechanisms.

STEAP1 gene is overexpressed in several kinds of tumors, particularly in prostate cancer. Besides STEAP1, there is another related gene, STEAP1B, which may encode two different transcripts. Although several studies have been pointing STEAP1 as a putative immunotherapeutic target and biomarker, the mechanisms underlying its regulation are not fully understood.

STEAP1 is overexpressed in prostate cancer and prostatic intraepithelial neoplasia lesions, and it is positively associated with Gleason score.

Background: Six transmembrane epithelial antigen of the prostate 1 (STEAP1) is a transmembrane protein of epithelial cells, mostly located at cell-cell junctions, and is overexpressed in several types of tumors, particularly prostate cancer. Several studies have pointed STEAP1 as a biomarker, but the clinical significance of its overexpression is not fully understood. Therefore, we aimed to establish the association of STEAP1 immunoreactivity with histologic diagnosis and clinical data of patients.

Six transmembrane epithelial antigen of the prostate 1 is down-regulated by sex hormones in prostate cells.

Background: STEAP1 is over-expressed in several types of tumors, especially prostate cancer, where it is localized in the plasma membrane of epithelial cells, at cell-cell junctions. Its role in prostate carcinogenesis and its regulation in prostate cells remain unknown. Therefore, we propose to study the effect of sex hormones in the regulation of STEAP1 expression in prostate cells in vitro and in vivo.

STEAP proteins: from structure to applications in cancer therapy.

The human 6-transmembrane epithelial antigen of prostate (STEAP) family comprises STEAP1, STEAP2, STEAP3, and STEAP4. All of these proteins are unique to mammals and share an innate activity as metalloreductases, indicating their importance in metal metabolism. Overall, they participate in a wide range of biologic processes, such as molecular trafficking in the endocytic and exocytic pathways and control of cell proliferation and apoptosis.

Neuroprotective and neuroregenerative properties of metallothioneins.

Metallothioneins (MTs) are low-molecular weight cysteine- and metal-rich proteins with unquestionable metal binding capacity, antioxidant and anti-inflammatory properties, and a clear involvement in diverse physiological actions as inhibition of proapoptotic mechanisms, enhancement of cell survival, and tissue regeneration. Concurrent with this wide array of functions, MT-1/2 have been implicated in neuroprotection and neuroregeneration. The zinc binding capacity and antioxidant properties of MTs may account for most of their physiological features in the brain.

Human metallothioneins 2 and 3 differentially affect amyloid-beta binding by transthyretin.

Transthyretin (TTR), an amyloid-beta (Abeta) scavenger protein, and metallothioneins 2 and 3 (MT2 and MT3), low molecular weight metal-binding proteins, have recognized impacts in Abeta metabolism. Because TTR binds MT2, an ubiquitous isoform of the MTs, we investigated whether it also interacts with MT3, an isoform of the MTs predominantly expressed in the brain, and studied the role of MT2 and MT3 in human TTR-Abeta binding. The TTR-MT3 interaction was characterized by yeast two-hybrid assays, saturation-binding assays, co-immunolocalization and co-immunoprecipitation.

Progesterone enhances transthyretin expression in the rat choroid plexus in vitro and in vivo via progesterone receptor.

Depletion of ovarian hormones 17β-estradiol (E2) and progesterone (P) after menopause may contribute to the decline in cognitive performance and increases the risk of Alzheimer's disease (AD) in women, striking the importance of understanding the regulation of pivotal proteins involved in AD pathogenesis by ovarian hormones. Transthyretin (TTR) is now recognized as one of such proteins due to its ability to sequester and degrade amyloid β (Aβ) into less harmful peptides and preventing their aggregation. We have previously demonstrated that E2 enhances TTR expression.

Androgen receptor is expressed in murine choroid plexus and downregulated by 5alpha-dihydrotestosterone in male and female mice.

The choroid plexuses (CPs) of the brain form a unique interface between the peripheral blood and the cerebrospinal fluid (CSF). CPs produce several neuroprotective peptides, which are secreted into the CSF. Despite their importance in neuroprotection, the mechanisms underlying the regulation of most of these peptides in CPs remain unknown.

STEAP1 is over-expressed in breast cancer and down-regulated by 17beta-estradiol in MCF-7 cells and in the rat mammary gland.

Six transmembrane epithelial antigen of the prostate 1 (STEAP1) was identified as a prostate-specific cell-surface antigen over-expressed in prostate cancer, and in human cancer cell lines obtained from several other tissues. Its cell surface location in all tumor types analyzed so far, and its absence in most vital organs in humans, turned STEAP1 into a potential target for anti-tumor immunotherapy. This study provides experimental evidence that STEAP1 is also over-expressed in human breast cancer cases, and in normal breast tissue adjacent to breast tumors, where it is localized in the cell membrane of epithelial cells.

Regucalcin is expressed in rat mammary gland and prostate and down-regulated by 17beta-estradiol.

Regucalcin is involved in maintenance of calcium homeostasis due to the activation of Ca2+ pumping enzymes in the plasma membrane. It has a suppressive effect in cell proliferation, DNA and RNA synthesis, and may be associated with the abnormal cell division on tumor tissues. On the other hand both estrogens and Ca2+ are implicated in breast and prostate cancer but there are no studies focused on the expression of regucalcin in rat mammary gland or prostate.

High resolution crystal structures of piscine transthyretin reveal different binding modes for triiodothyronine and thyroxine.

Transthyretin (TTR) is an extracellular transport protein involved in the distribution of thyroid hormones and vitamin A. So far, TTR has only been found in vertebrates, of which piscine TTR displays the lowest sequence identity with human TTR (47%). Human and piscine TTR bind both thyroid hormones 3,5,3'-triiodo-l-thyronine (T(3)) and 3,5,3',5'-tetraiodo-l-thyronine (thyroxine, T(4)).

Transthyretin in fish: state of the art.

Relatively little is known about thyroid hormone-binding proteins in fish and, until recently, the thyroid hormones (THs), thyroxine (T4) and triiodothyronine (T3), had only been found in fish plasma bound to albumin and lipoproteins. Recently, transthyretin (TTR) was cloned in a teleost fish, the sea bream (sb); it is composed of 130 amino acids and shares 47-54% sequence similarity with other vertebrate TTR and binds preferentially T3. Homology modelling of sbTTR based upon the crystallographic structure of TTR in human, rat and chicken reveals similar monomer-monomer and dimer-dimer interfaces and a conserved tetrameric structure.

Quantification of prolactin (PRL) and PRL receptor messenger RNA in gilthead seabream (Sparus aurata) after treatment with estradiol-17beta.

Prolactin (PRL) in fish is considered to be an osmoregulatory hormone, although some studies suggest that it may influence the production of steroid hormones in the gonads. The objective of the present study was to establish if PRL is involved in reproduction of the gilthead seabream-a protandrous hermaphrodite. Adult and juvenile gilthead seabream received implants of estradiol-17beta (E(2)) for 1 wk during the breeding season, and the mRNA expressions of PRL and PRL receptor (sbPRLR) were determined.