The microtubule-binding protein tau has been implicated in the pathogenesis of Alzheimer's disease and related disorders. However, the mechanisms underlying tau-mediated neurotoxicity remain unclear. ...We created a genetic model of tau-related neurodegenerative disease by expressing wild-type and mutant forms of human tau in the fruit fly Drosophila melanogaster. Transgenic flies showed key features of the human disorders: adult onset, progressive neurodegeneration, early death, enhanced toxicity of mutant tau, accumulation of abnormal tau, and relative anatomic selectivity. However, neurodegeneration occurred without the neurofibrillary tangle formation that is seen in human disease and some rodent tauopathy models. This fly model may allow a genetic analysis of the cellular mechanisms underlying tau neurotoxicity.
We report on the role of hexamethylene-bis-acetamide-inducible protein 1 (HEXIM1) as an inhibitor of metastasis. HEXIM1 expression is decreased in human metastatic breast cancers when compared with ...matched primary breast tumors. Similarly we observed decreased expression of HEXIM1 in lung metastasis when compared with primary mammary tumors in a mouse model of metastatic breast cancer, the polyoma middle T antigen (PyMT) transgenic mouse. Re-expression of HEXIM1 (through transgene expression or localized delivery of a small molecule inducer of HEXIM1 expression, hexamethylene-bis-acetamide) in PyMT mice resulted in inhibition of metastasis to the lung. Our present studies indicate that HEXIM1 downregulation of HIF(-)1α protein allows not only for inhibition of vascular endothelial growth factor-regulated angiogenesis, but also for inhibition of compensatory pro-angiogenic pathways and recruitment of bone marrow-derived cells (BMDCs). Another novel finding is that HEXIM1 inhibits cell migration and invasion that can be partly attributed to decreased membrane localization of the 67 kDa laminin receptor, 67LR, and inhibition of the functional interaction of 67LR with laminin. Thus, HEXIM1 re-expression in breast cancer has therapeutic advantages by simultaneously targeting more than one pathway involved in angiogenesis and metastasis. Our results also support the potential for HEXIM1 to indirectly act on multiple cell types to suppress metastatic cancer.
Inhibition of multiple enzymes of the arachidonic acid cascade leads to synergistic anti-inflammatory effects. Merging of 5-lipoxygenase (5-LOX) and soluble epoxide hydrolase (sEH) pharmacophores led ...to the discovery of a dual 5-LOX/sEH inhibitor, which was subsequently optimized in terms of potency toward both targets and metabolic stability. The optimized lead structure displayed cellular activity in human polymorphonuclear leukocytes, oral bioavailability, and target engagement in vivo and demonstrated profound anti-inflammatory and anti-fibrotic efficiency in a kidney injury model caused by unilateral ureteral obstruction in mice. These results pave the way for investigating the therapeutic potential of dual 5-LOX/sEH inhibitors in other inflammation- and fibrosis-related disease models.
Purpose
Evidence suggests that partners of men with prostate cancer (CaP) experience greater psychosocial distress compared with men themselves. However, the experiences of partners of high-risk (1 ...in 4) Black African (BA) and Black Caribbean (BC) men with CaP remain poorly understood as existing research has predominantly focused on Caucasian populations. This study aimed to address this gap by exploring partners’ experience and support needs as influenced both by the specific impacts of CaP, treatment side effects and socio-cultural context.
Methods
Using a constructivist grounded theory approach, eight face-to-face, two Skype and one telephone interviews were conducted with eligible partners (
n
= 11). The interviews were analysed using constant comparison following key stages of open, focused and theoretical coding.
Results
Three broad categories emerged which described participants’ experiences: ‘partner in the passenger seat’, ‘care-giving on an isolating journey’, and ‘coping as a partner’. Findings showed that BA and BC cultural marital context influenced how partners experienced and traversed the CaP journey. Peripheral involvement in decision-making, communication restrictions, limited access to support and lack of recognition for their experiences and needs further contributed to partners’ psychological and emotional distress.
Conclusions
Cultural beliefs, behaviours and values should be taken into account when developing psychosocial support for partners and their men with CaP. Specifically providing information focused on partners and including them in the CaP care pathway could help ensure that partners’ needs are recognised and improve marital communications. This could potentially help partners and their men to identify acceptable ways of supporting each other throughout the CaP experience.
Estrogen receptor alpha (ERalpha) regulates transcription of specific genes and is believed to play a major role in breast tumorigenesis. We previously identified estrogen down regulated gene 1 (EDG1 ...(also known as HEXIM1)) using the C-terminus of ERalpha (E/F domain) as bait in yeast two-hybrid screenings. Here we report on the role of EDG1 as a coregulator of ERalpha transcriptional activity. We observe an interaction between EDG1 and ERalpha. EDG1 inhibits the transcriptional activity of ERalpha and this is dependent upon the C-terminus of EDG1. The C-terminus of EDG1/HEXIM1 was recently shown to inhibit the positive transcription elongation factor b (P-TEFb) by interacting with the cyclin T1 subunit. Here we show that ERalpha interacts with cyclin T1, cyclin T1 and ER co-occupancy on the promoter region of an ER target gene, and that this interaction plays an important role in ERalpha-induced gene expression. The interaction of ERalpha with cyclin T1 also allows ERalpha to compete with EDG1 for cyclin T1, and may release cyclin T1 from EDG1 repression. Conversely, increased EDG1 expression results in inhibition of cyclin T1 recruitment and ERalpha DNA binding. Our results support a novel functional interaction between ERalpha and cyclin T1 that is modulated by EDG1.
Lifetime exposure to estrogens is a major risk factor in breast cancer, but the mechanism for this action is not fully defined. To better determine this mechanism, the activation domain of estrogen ...receptor (ER) alpha was used in yeast two-hybrid screenings. These screenings resulted in the identification of a novel antiproliferative protein, estrogen down-regulated gene 1 (EDG1), of which the mRNA and protein were shown to be down-regulated directly by estrogens. Our studies additionally suggested an important role for EDG1 in ER alpha-mediated breast cancer development. Analysis of 43 invasive breast cancer samples and 40 adjacent normal breast samples demonstrated EDG1 protein levels to be significantly higher in normal breast epithelial tissue as compared with breast epithelial tumor tissue. EDG1 expression levels were also correlated with the proliferation activity and ER alpha status of the tumors to examine the prognostic value of EDG1 in invasive breast tumors. EDG1 expression was more disassociated from proliferative activity as compared with ER alpha expression in tumor cells. A growth regulatory function for EDG1 is additionally indicated by studies wherein overexpression of EDG1 protein in breast cells resulted in decreased cell proliferation and decreased anchorage-independent growth. Conversely, inhibiting EDG1 expression in breast cells resulted in increased breast cell growth. Thus, we have identified a novel growth inhibitor that is down-regulated by estrogens and colocalizes with ER alpha in breast tissue. These studies support a role for EDG1 in breast cancer.
The regulation of the quinone reductase (QR) gene as well as other genes involved in detoxification is known to be mediated by an electrophile/antioxidant response element (EpRE/ARE). We have ...previously observed that QR is up-regulated by the antiestrogen trans-hydroxytamoxifen in breast cancer cells. QR gene regulation by the antiestrogen-occupied estrogen receptor (ER) is mediated by the EpRE-containing region of the human QR gene, and the ER is one of the complex of proteins that binds to the EpRE. In an effort to further understand the mechanism for ER regulation of QR gene we identified other protein factors that regulate QR gene transcriptional activity in breast cancer cells. One of these protein factors, hPMC2 (human homolog of Xenopus gene whichprevents mitotic catastrophe), directly binds to the EpRE and interacts with the ER in yeast genetic screening and in vitro assays. Interestingly hPMC2 interacts more strongly to ERβ when compared with ERα. In transient transfection assays using reporter constructs containing the EpRE, hPMC2 alone can slightly activate reporter in ER-negative MDA-MB-231 breast cancer cells. The activation of QR gene activity by hPMC2 is enhanced in the presence of ERβ.
This article summarises the activities of the Bacterial Viruses Subcommittee of the International Committee on Taxonomy of Viruses for the period of March 2021−March 2022. We provide an overview of ...the new taxa proposed in 2021, approved by the Executive Committee, and ratified by vote in 2022. Significant changes to the taxonomy of bacterial viruses were introduced: the paraphyletic morphological families
Podoviridae
,
Siphoviridae
, and
Myoviridae
as well as the order
Caudovirales
were abolished, and a binomial system of nomenclature for species was established. In addition, one order, 22 families, 30 subfamilies, 321 genera, and 862 species were newly created, promoted, or moved.
While biocatalysis is increasingly incorporated into drug development pipelines, it is less commonly used in the early stages of drug discovery. By engineering a protein to produce a chiral motif ...with a derivatizable functional handle, biocatalysts can be used to help generate diverse building blocks for drug discovery. Here we show the engineering of two variants of Rhodothermus marinus nitric oxide dioxygenase (RmaNOD) to catalyze the formation of cis- and trans-diastereomers of a pinacolboronate-substituted cyclopropane which can be readily derivatized to generate diverse stereopure cyclopropane building blocks.
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