Glycolysis is essential to support cancer cell proliferation, even in the presence of oxygen. The transcriptional co-regulator RIP140 represses the activity of transcription factors that drive cell proliferation and metabolism and plays a role in mammary tumorigenesis. Here we use cell proliferation and metabolic assays to demonstrate that RIP140-deficiency causes a glycolysis-dependent increase in breast tumor growth.
View Article and Find Full Text PDFPancreas transcription factor 1a (PTF1a) plays a crucial role in the early development of the pancreas and in the maintenance of the acinar cell phenotype. Several transcriptional mechanisms regulating expression of PTF1a have been identified. However, regulation of PTF1a protein stability and degradation is still unexplored.
View Article and Find Full Text PDFPurpose: Receptor-interacting protein of 140 kDa (RIP140) is a transcriptional cofactor for nuclear receptors involved in reproduction and energy homeostasis. Our aim was to investigate its role in the regulation of E2F1 activity and target genes both in breast cancer cell lines and in tumor biopsies.
Experimental Design: Glutathione S-transferase pull-down assays, coimmunoprecipitation experiments, and chromatin immunoprecipitation analysis were used to evidence interaction between RIP140 and E2F1.
The nuclear receptor superfamily comprises ligand-regulated transcription factors that control various developmental and physiological pathways. These receptors share a common modular structure and regulate gene expression through the recruitment of a large set of coregulatory proteins. These transcription cofactors regulate, either positively or negatively, chromatin structure and transcription initiation.
View Article and Find Full Text PDFWhile parathyroid hormone type 1 receptor (PTH1R)-mediated vasodilatory, cardiac stimulatory, and renin-activating effects of exogenous PTH/PTH-related protein (PTHrP) are acknowledged, interactions of endogenous PTHrP with these systems remain unclear, mainly because the unavailability of viable PTHrP/PTH1R knockout mice. Transgenic mice overexpressing PTH1R in smooth muscle strongly have supported the PTHrP/PTH1R system as a cardiovascular system (CVS) regulator, but the consequences on renovascular (RVS) and renin-angiotensin systems (RAS) have not been explored in these studies. The aim was to develop a model in which one could study the consequences on CVS, RVS, and RAS of generalized PTH1R overexpression.
View Article and Find Full Text PDFAlthough lower than in brain, the type 2 PTH receptor (PTH2-R) has been shown to be expressed throughout the cardiovascular system. Tuberoinfundibular peptide (TIP) purified from brain is thought to be the endogenous selective ligand of the PTH2-R. In the present studies, TIP and PTH2-R mRNA expressions were evidenced by RT-PCR in rat intrarenal arteries as well as in renovascular smooth muscle cells cultured from these arteries.
View Article and Find Full Text PDFThese studies examine whether PTHrP(1-36), a vasodilator, modulates BP and renal vascular resistance (RVR) in spontaneously hypertensive rat (SHR). Within the kidney of normotensive rats, PTHrP(1-36) was enriched in vessels. In vessels of SHR, PTHrP was upregulated by 40% and type 1 PTH receptor (PTH1R) was downregulated by 65% compared with normotensive rats.
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