Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:Q9UIJ5 (Rec)
 58,342 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tuberous sclerosis complex proteins 1-2 (TSC1-TSC2) complex integrates both nutrient and hormonal signaling and is a critical negative regulator of mammalian target of rapamycin (mTOR) complex 1. The use of different beta-cell lines expressing or not the insulin receptor (IR(+/+) and IR(-/-)) or with a reconstituted expression of IR isoform A or B (Rec A and Rec B) revealed that both phosphatidylinositol 3-kinase/Akt/TSC/mTOR complex 1 and MAPK kinase/ERK pathways mediate insulin signaling in IR(+/+)-, IRA-, or IRB-expressing cells. However, glucose signaling was mediated by MAPK kinase/ERK and AMP-activated protein kinase pathways as assessed in IR(-/-) cells. The effect of insulin on Akt phosphorylation was completely inhibited by the use of the phosphatidylinositol 3-kinase inhibitor wortmannin in IR(+/+) and Rec B cells, a partial inhibitory effect being observed in Rec A cell line. The knockdown of TSC2 expression up-regulated the downstream basal phosphorylation of 70-kDa ribosomal protein S6 kinase (p70S6K) and mTOR. More importantly, upregulation of p70S6K signaling impaired insulin-stimulated phosphorylation of Akt Ser(473) and p70S6K in IR(+/+) and Rec B but not in Rec A cell lines. In fact, insulin receptor substrate-1 Ser(307) phosphorylation signal in Rec B was stronger than in Rec A cell line during insulin action. Rec A cells induced a higher proliferation rate compared with Rec B or IR(+/+) during serum stimulation. Thus, we propose that the regulation of TSC2 phosphorylation by insulin or glucose independently integrates beta-cell proliferation signaling, the relative expression of IRA or IRB isoforms in pancreatic beta cells playing a major role.
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PMID:Role of the TSC1-TSC2 complex in the integration of insulin and glucose signaling involved in pancreatic beta-cell proliferation. 2042 78

It has been reported that metformin, a biguanide derivative widely used in type II diabetic patients, has antitumor activities in some cancers by activation of AMP-activated protein kinase (AMPK). But its role in nasopharyngeal carcinoma (NPC) is not known. Here, we reported for the first time that 1-50 mM of metformin in a dose- and time-dependent manner suppressed cell proliferation and colony formation in NPC cell line, C666-1. Further studies revealed that the protein level of cyclin D1 decreased and the percentage of the cells in G0/G1 phase increased by 5 mM metformin treatment. Metformin also induced the phosphorylation of AMPK (T172) in a time-dependent manner. Mammalian target of rapamycin complex 1 (mTORC1), which is negatively regulated by AMPK and plays a central role in cell growth and proliferation, was inhibited by metformin, as manifested by dephosphorylation of its downstream targets 40S ribosomal S6 kinase 1 (S6K1) (T389), the eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1) (T37/46) and S6 (S235/236) in C666-1 cells. In a summary, metformin prevents proliferation of C666-1 cells by down-regulating cyclin D1 level and inducing G1 cell cycle arrest. AMPK-mediated inhibition of mTORC1 signaling may be involved in this process.
Anat Rec (Hoboken) 2011 Aug
PMID:Metformin induces G1 cell cycle arrest and inhibits cell proliferation in nasopharyngeal carcinoma cells. 2171 84

The usefulness of various pathways inhibitors, Everolimus, an inhibitor of mammalian target of rapamycin (mTOR), Infliximab, a monoclonal antibody which blocks the tumor necrosis factor-a (TNF-a), Erlotinib, a tyrosine protein kinase inhibitor of the epidermal growth factor receptor (EGFR), Metformin, an activator of AMP-activated protein kinase enzyme (AMPK) and vascular permeability reducers were explored in an ovarian hyperstimulation syndrome (OHSS) rat model. Sixty-three female Wistar rats were randomly divided in seven groups. The control group received saline, while the OHSS group received recombinant -- follicle-stimulating hormone (rec-FSH) for four consecutive days. The other five groups received rec-FSH for 4 d and Everolimus daily, Infliximab once, Erlotinib daily, Metformin daily and Vitamin C daily, respectively. All groups received human chorionic gonadotropin (hCG) at the fifth day. The efficacy of Everolimus administration for various intervals was also explored. Significantly reduced ovarian weight was observed in the Everolimus group (rec-FSH + hCG + mTOR inhibitor) compared to the OHSS group (p < 0.001). The Everolimus group also showed the lowest progesterone (PRG) concentration (p = 0.007). The Erlotinib group (rec-FSH + hCG + EGFR inhibitor) presented with the lowest graafian follicle number, while the Everolimus group was characterized by the lowest corpus luteum number. The vascular permeability and the estradiol levels did not differ between groups. Finally, the Everolimus intra-comparison showed no difference in all measured outcomes. Studying the different pathways linked to vascular endothelial growth factor (VEGF) pathway, we conclude that targeting mTOR pathways is beneficial for reducing ovarian weight and PRG levels in an OHSS animal model.
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PMID:Everolimus, an mTOR pathway inhibitor, is highly successful on ovarian hyperstimulation syndrome by reducing ovarian weight and progesterone levels: a preclinical experimental randomized controlled study. 2617 31