Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
Compound
Query: UNIPROT:P43146 (
tumour suppressor
)
5,935
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Humans, like other complex aerobic organisms, possess highly evolved systems for the delivery of dioxygen to all the cells of the body. These systems are regulated since excessive levels of dioxygen are toxic. In animals hypoxia causes an increase in the transcription levels of specific genes, including those encoding for vascular endothelial growth factor and erythropoietin. At the transcriptional level, the hypoxic response is mediated by hypoxia-inducible factor (HIF), an alpha,beta-heterodimeric protein. HIF-beta is constitutively present, but HIF-alpha levels are regulated by dioxygen. Under hypoxic conditions, levels of HIF-alpha rise, allowing its dimerization with HIF-beta and enabling transcriptional activation. Under normoxic conditions both the level of HIF-alpha and its ability to enable transcription are directly controlled by its post-translational oxidation by oxygenases. Hydroxylation of HIF-alpha at either of two conserved prolyl residues enables its recognition by the von Hippel-Lindau
tumour suppressor
protein which targets it for proteasomal degradation. Hydroxylation of an asparaginyl residue in the C-terminal transactivation domain of HIF-alpha directly prevents its interaction with the coactivator p300 from the transcription complex. Hydroxylation of HIF-alpha is catalysed by members of the iron (II) and 2-oxoglutarate dependent oxygenase family. In humans, three prolyl-hydroxylase isozymes (PHD1-3, for prolyl hydroxylase domain enzymes) and an asparaginyl hydroxylase (FIH, for factor inhibiting HIF) have been identified. Recent studies have identified additional post-translational modifications of HIF-alpha including acetylation and phosphorylation. Modulation of the HIF mediated hypoxic response is of potential use in a wide range of disease states including
cardiovascular disease
and cancer. Here we review current knowledge of the HIF pathway focusing on its regulation by dioxygen and discussion of potential targets and challenges in attempts to modulate the pathway for medicinal application.
...
PMID:Modulating the hypoxia-inducible factor signaling pathway: applications from cardiovascular disease to cancer. 1503 87
Epigenetic changes are inherited alterations in DNA that affect gene expression and function without altering the DNA sequence. DNA methylation is one epigenetic process implicated in human disease that is influenced by diet. DNA methylation involves addition of a 1-C moiety to cytosine groups in DNA. Methylated genes are not transcribed or are transcribed at a reduced rate. Global under-methylation (hypomethylation) and site-specific over-methylation (hypermethylation) are common features of human tumours. DNA hypomethylation, leading to increased expression of specific proto-oncogenes (e.g. genes involved in proliferation or metastasis) can increase the risk of cancer as can hypermethylation and reduced expression of
tumour suppressor
(TS) genes (e.g. DNA repair genes). DNA methyltransferases (DNMT), together with the methyl donor S-adenosylmethionine (SAM), facilitate DNA methylation. Abnormal DNA methylation is implicated not only in the development of human cancer but also in
CVD
. Polyphenols, a group of phytochemicals consumed in significant amounts in the human diet, effect risk of cancer. Flavonoids from tea, soft fruits and soya are potent inhibitors of DNMT in vitro, capable of reversing hypermethylation and reactivating TS genes. Folates, a group of water-soluble B vitamins found in high concentration in green leafy vegetables, regulate DNA methylation through their ability to generate SAM. People who habitually consume the lowest level of folate or with the lowest blood folate concentrations have a significantly increased risk of developing several cancers and
CVD
. This review describes how flavonoids and folates in the human diet alter DNA methylation and may modify the risk of human colon cancer and
CVD
.
...
PMID:Epigenetic modifications and human pathologies: cancer and CVD. 2106 30
Cardiovascular disease
is a leading cause of death worldwide, particularly in Western societies. During an ischaemic insult, ventricular pressure from the heart is diminished as a result of cardiac myocyte death by necrosis and apoptosis. Autophagy is a process whereby cells catabolise intracellular proteins in order to generate ATP in times of stress such as nutrient starvation and hypoxia. Emerging evidence suggests that autophagy plays a positive role in cardiac myocyte survival during periods of cellular stress performing an important damage limitation function. By promoting cell survival, cardiac myocyte loss is reduced thereby minimising the potential of heart failure. In contrast, it has been reported that autophagy can also be a form of cell death. By considering the various animal models of autophagy, we examine the role of the Signal Transducers and Activator of Transcription (STAT) proteins in the autophagic response. Additionally we review the role of the
tumour suppressor
, p53 and its family member p73 and their potential role in the autophagic response.
...
PMID:Autophagy in the stress-induced myocardium. 2220 25
Oxygen is essential for eukaryotic life and is inextricably linked to the evolution of multicellular organisms. Proper cellular response to changes in oxygen tension during normal development or pathological processes, such as
cardiovascular disease
and cancer, is ultimately regulated by the transcription factor, hypoxia-inducible factor (HIF). Over the past decade, unprecedented molecular insight has been gained into the mammalian oxygen-sensing pathway involving the canonical oxygen-dependent prolyl-hydroxylase domain-containing enzyme (PHD)-von Hippel-Lindau
tumour suppressor
protein (pVHL) axis and its connection to cellular metabolism. Here we review recent notable advances in the field of hypoxia that have shaped a more complex model of HIF regulation and revealed unique roles of HIF in a diverse range of biological processes, including immunity, development and stem cell biology.
...
PMID:The updated biology of hypoxia-inducible factor. 2256 52
The calcium-sensing receptor (CaSR) plays a pivotal role in systemic calcium metabolism by regulating parathyroid hormone secretion and urinary calcium excretion. The CaSR is ubiquitously expressed, implying a wide range of functions regulated by this receptor. Abnormal CaSR function affects the development of both calciotropic disorders such as hyperparathyroidism, and non-calciotropic disorders such as
cardiovascular disease
and cancer, which are the leading causes of mortality worldwide. The CaSR is able to bind a plethora of ligands; it interacts with multiple G protein subtypes, and regulates highly divergent downstream signalling pathways, depending on the cellular context. The CaSR is a key regulator for such diverse processes as hormone secretion, gene expression, inflammation, proliferation, differentiation, and apoptosis. Due to this pleiotropy, the CaSR is able to regulate cell fate and is implicated in the development of many types of benign or malignant tumours of the breast, prostate, parathyroid, and colon. In cancer, the CaSR appears to have paradoxical roles, and depending on the tissue involved, it is able to prevent or promote tumour growth. In tissues like the parathyroid or colon, the CaSR inhibits proliferation and induces terminal differentiation of the cells. Therefore, loss of the receptor, as seen in colorectal or parathyroid tumours, confers malignant potential, suggestive of a
tumour suppressor
role. In contrast, in prostate and breast tumours the expression of the CaSR is increased and it seems that it favours metastasis to the bone, acting as an oncogene. Deciphering the molecular mechanism driving the CaSR in the different tissues could lead to development of new allosteric drug compounds that selectively target the CaSR and have therapeutic potential for cancer. This article is part of a Special Issue entitled: Calcium and Cell Fate. Guest Editors: Jacques Haiech, Claus Heizmann, Joachim Krebs, Thierry Capiod and Olivier Mignen.
...
PMID:The calcium-sensing receptor and the hallmarks of cancer. 2660 8
The reactive dicarbonyl metabolite methylglyoxal (MG) is the precursor of the major quantitative advanced glycation endproducts (AGEs) in physiological systems - arginine-derived hydroimidazolones and deoxyguanosine-derived imidazopurinones. The glyoxalase system in the cytoplasm of cells provides the primary defence against dicarbonyl glycation by catalysing the metabolism of MG and related reactive dicarbonyls. Dicarbonyl stress is the abnormal accumulation of dicarbonyl metabolites leading to increased protein and DNA modification contributing to cell and tissue dysfunction in ageing and disease. It is produced endogenously by increased formation and/or decreased metabolism of dicarbonyl metabolites. Dicarbonyl stress contributes to ageing, disease and activity of cytotoxic chemotherapeutic agents. It contributes to ageing through age-related decline in glyoxalase 1 (Glo-1) activity. Glo-1 has a dual role in cancer as a
tumour suppressor
protein prior to tumour development and mediator of multi-drug resistance in cancer treatment, implicating dicarbonyl glycation of DNA in carcinogenesis and dicarbonyl-driven cytotoxicity in mechanism of action of anticancer drugs. Glo-1 is a driver of
cardiovascular disease
, likely through dicarbonyl stress-driven dyslipidemia and vascular cell dysfunction. Dicarbonyl stress is also a contributing mediator of obesity and vascular complications of diabetes. There are also emerging roles in neurological disorders. Glo-1 responds to dicarbonyl stress to enhance cytoprotection at the transcriptional level through stress-responsive increase of Glo-1 expression. Small molecule Glo-1 inducers are in clinical development for improved metabolic, vascular and renal health and Glo-1 inhibitors in preclinical development for multidrug resistant cancer chemotherapy.
...
PMID:Dicarbonyls and glyoxalase in disease mechanisms and clinical therapeutics. 2740 12
The genomic CDKN2A/B locus, encoding p16
INK4a
among others, is linked to an increased risk for
cardiovascular disease
and type 2 diabetes. Obesity is a risk factor for both
cardiovascular disease
and type 2 diabetes. p16
INK4a
is a cell cycle regulator and
tumour suppressor
. Whether it plays a role in adipose tissue formation is unknown. p16
INK4a
knock-down in 3T3/L1 preadipocytes or p16
INK4a
deficiency in mouse embryonic fibroblasts enhanced adipogenesis, suggesting a role for p16
INK4a
in adipose tissue formation. p16
INK4a
-deficient mice developed more epicardial adipose tissue in response to the adipogenic peroxisome proliferator activated receptor gamma agonist rosiglitazone. Additionally, adipose tissue around the aorta from p16
INK4a
-deficient mice displayed enhanced rosiglitazone-induced gene expression of adipogenic markers and stem cell antigen, a marker of bone marrow-derived precursor cells. Mice transplanted with p16
INK4a
-deficient bone marrow had more epicardial adipose tissue compared to controls when fed a high-fat diet. In humans, p16
INK4a
gene expression was enriched in epicardial adipose tissue compared to other adipose tissue depots. Moreover, epicardial adipose tissue from obese humans displayed increased expression of stem cell antigen compared to lean controls, supporting a bone marrow origin of epicardial adipose tissue. These results show that p16
INK4a
modulates epicardial adipose tissue development, providing a potential mechanistic link between the genetic association of the CDKN2A/B locus and
cardiovascular disease
risk.
...
PMID:The tumour suppressor CDKN2A/p16
INK4a
regulates adipogenesis and bone marrow-dependent development of perivascular adipose tissue. 2886 98