60 research outputs found
Activation of the Farnesoid X-receptor in breast cancer cell lines results in cytotoxicity but not increased migration potential
Breast cancer is the commonest form of cancer in women, but successful treatment is confounded by the heterogeneous nature of breast tumours: Effective treatments exist for hormone-sensitive tumours, but triple-negative breast cancer results in poor survival. An area of increasing interest is metabolic reprogramming, whereby drug-induced alterations in the metabolic landscape of a tumour slow tumour growth and/or increase sensitivity to existing therapeutics. Nuclear receptors are transcription factors central to the expression of metabolic and transport proteins, and thus represent potential targets for metabolic reprogramming. We show that activation of the nuclear receptor FXR, either by its endogenous ligand CDCA or the synthetic GW4064, leads to cell death in four breast cancer cell lines with distinct phenotypes: MCF-10A (normal), MCF-7 (receptor positive), MDA-MB-231 and MDA-MB-468 (triple negative). Furthermore, we show that the mechanism of cell death is predominantly through the intrinsic apoptotic pathway. Finally, we demonstrate that FXR agonists do not stimulate migration in breast cancer cell lines, an important potential adverse effect. Together, our data support the continued examination of FXR agonists as a novel class of therapeutics for the treatment of breast cancer
Nuclear receptors in vascular biology
Nuclear receptors sense a wide range of steroids and hormones (estrogens, progesterone, androgens, glucocorticoid, and mineralocorticoid), vitamins (A and D), lipid metabolites, carbohydrates, and xenobiotics. In response to these diverse but critically important mediators, nuclear receptors regulate the homeostatic control of lipids, carbohydrate, cholesterol, and xenobiotic drug metabolism, inflammation, cell differentiation and development, including vascular development. The nuclear receptor family is one of the most important groups of signaling molecules in the body and as such represent some of the most important established and emerging clinical and therapeutic targets. This review will highlight some of the recent trends in nuclear receptor biology related to vascular biology
A phase I dose-escalation study of enzalutamide in combination with the AKT inhibitor AZD5363 (capivasertib) in patients with metastatic castration-resistant prostate cancer.
Background Activation of the PI3K/AKT/mTOR pathway through loss of phosphatase and tensin homolog (PTEN) occurs in approximately 50% of patients with metastatic castration-resistant prostate cancer (mCRPC). Recent evidence suggests that combined inhibition of the androgen receptor (AR) and AKT may be beneficial in mCRPC with PTEN loss.Patients and methods mCRPC patients who previously failed abiraterone and/or enzalutamide, received escalating doses of AZD5363 (capivasertib) starting at 320 mg twice daily (b.i.d.) given 4 days on and 3 days off, in combination with enzalutamide 160 mg daily. The co-primary endpoints were safety/tolerability and determining the maximum tolerated dose and recommended phase II dose; pharmacokinetics, antitumour activity, and exploratory biomarker analysis were also evaluated.Results Sixteen patients were enrolled, 15 received study treatment and 13 were assessable for dose-limiting toxicities (DLTs). Patients were treated at 320, 400, and 480 mg b.i.d. dose levels of capivasertib. The recommended phase II dose identified for capivasertib was 400 mg b.i.d. with 1/6 patients experiencing a DLT (maculopapular rash) at this level. The most common grade ≥3 adverse events were hyperglycemia (26.7%) and rash (20%). Concomitant administration of enzalutamide significantly decreased plasma exposure of capivasertib, though this did not appear to impact pharmacodynamics. Three patients met the criteria for response (defined as prostate-specific antigen decline ≥50%, circulating tumour cell conversion, and/or radiological response). Responses were seen in patients with PTEN loss or activating mutations in AKT, low or absent AR-V7 expression, as well as those with an increase in phosphorylated extracellular signal-regulated kinase (pERK) in post-exposure samples.Conclusions The combination of capivasertib and enzalutamide is tolerable and has antitumour activity, with all responding patients harbouring aberrations in the PI3K/AKT/mTOR pathway.Clinical trial number NCT02525068
The Epoxygenases CYP2J2 Activates the Nuclear Receptor PPARα In Vitro and In Vivo
Peroxisome proliferator-activated receptors (PPARs) are a family of three (PPARalpha, -beta/delta, and -gamma) nuclear receptors. In particular, PPARalpha is involved in regulation of fatty acid metabolism, cell growth and inflammation. PPARalpha mediates the cardiac fasting response, increasing fatty acid metabolism, decreasing glucose utilisation, and is the target for the fibrate lipid-lowering class of drugs. However, little is known regarding the endogenous generation of PPAR ligands. CYP2J2 is a lipid metabolising cytochrome P450, which produces anti-inflammatory mediators, and is considered the major epoxygenase in the human heart.Expression of CYP2J2 in vitro results in an activation of PPAR responses with a particular preference for PPARalpha. The CYP2J2 products 8,9- and 11-12-EET also activate PPARalpha. In vitro, PPARalpha activation by its selective ligand induces the PPARalpha target gene pyruvate dehydrogenase kinase (PDK)4 in cardiac tissue. In vivo, in cardiac-specific CYP2J2 transgenic mice, fasting selectively augments the expression of PDK4.Our results establish that CYP2J2 produces PPARalpha ligands in vitro and in vivo, and suggests that lipid metabolising CYPs are prime candidates for the integration of global lipid changes to transcriptional signalling events
A phase I/II trial of AT9283, a selective inhibitor of aurora kinase in children with relapsed or refractory acute leukemia: challenges to run early phase clinical trials for children with leukemia.
Aurora kinases regulate mitosis and are commonly overexpressed in leukemia. This phase I/IIa study of AT9283, a multikinase inhibitor, was designed to identify maximal tolerated doses, safety, pharmacokinetics, and pharmacodynamic activity in children with relapsed/refractory acute leukemia. The trial suffered from poor recruitment and terminated early, therefore failing to identify its primary endpoints. AT9283 caused tolerable toxicity, but failed to show clinical responses. Future trials should be based on robust preclinical data that provide an indication of which patients may benefit from the experimental agent, and recruitment should be improved through international collaborations and early combination with established treatment strategies
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The influence of organizational culture and climate on entrepreneurial intentions among research scientists
Over the past decades, universities have increasingly become involved in entrepreneurial activities. Despite efforts to embrace their ‘third mission’, universities still demonstrate great heterogeneity in terms of their involvement in academic entrepreneurship. This papers adopts an institutional perspective to understand how organizational characteristics affect research scientists’ entrepreneurial intentions. Specifically, we study the impact of university culture and climate on entrepreneurial intentions, including intentions to spin off a company, to engage in patenting or licensing and to interact with industry through contract research or consulting. Using a sample of 437 research scientists from Swedish and German universities, our results reveal that the extent to which universities articulate entrepreneurship as a fundamental element of their mission fosters research scientists’ intentions to engage in spin-off creation and intellectual property rights, but not industry-science interaction. Furthermore, the presence of university role models positively affects research scientists’ propensity to engage in entrepreneurial activities, both directly and indirectly through entrepreneurial self-efficacy. Finally, research scientists working at universities which explicitly reward people for ‘third mission’ related output show higher levels of spin-off and patenting or licensing intentions. This study has implications for both academics and practitioners, including university managers and policy makers
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