Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.11.31 (AMP-activated protein kinase)
 13,065 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Triple-negative breast cancers (TNBCs) are heterogeneous and aggressive, with high mortality rates. TNBCs frequently respond to chemotherapy, yet many patients develop chemoresistance. The molecular basis and roles for tumor cell-stromal crosstalk in establishing chemoresistance are complex and largely unclear. Here we report molecular studies of paired TNBC patient-derived xenografts (PDXs) established before and after the development of chemoresistance. Interestingly, the chemoresistant model acquired a distinct KRASQ61R mutation that activates K-Ras. The chemoresistant KRAS-mutant model showed gene expression and proteomic changes indicative of altered tumor cell metabolism. Specifically, KRAS-mutant PDXs exhibited increased redox ratios and decreased activation of AMPK, a protein involved in responding to metabolic homeostasis. Additionally, the chemoresistant model exhibited increased immunosuppression, including expression of CXCL1 and CXCL2, cytokines responsible for recruiting immunosuppressive leukocytes to tumors. Notably, chemoresistant KRAS-mutant tumors harbored increased numbers of granulocytic myeloid-derived suppressor cells (gMDSCs). Interestingly, previously established Ras/MAPK-associated gene expression signatures correlated with myeloid/neutrophil-recruiting CXCL1/2 expression and negatively with T cell-recruiting chemokines (CXCL9/10/11) across patients with TNBC, even in the absence of KRAS mutations. MEK inhibition induced tumor suppression in mice while reversing metabolic and immunosuppressive phenotypes, including chemokine production and gMDSC tumor recruitment in the chemoresistant KRAS-mutant tumors. These results suggest that Ras/MAPK pathway inhibitors may be effective in some breast cancer patients to reverse Ras/MAPK-driven tumor metabolism and immunosuppression, particularly in the setting of chemoresistance.
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PMID:MEK activation modulates glycolysis and supports suppressive myeloid cells in TNBC. 3263 21

Cancer is characterized as a complex disease caused by coordinated alterations of multiple signaling pathways. The Ras/RAF/MEK/ERK (MAPK) signaling is one of the best-defined pathways in cancer biology, and its hyperactivation is responsible for over 40% human cancer cases. To drive carcinogenesis, this signaling promotes cellular overgrowth by turning on proliferative genes, and simultaneously enables cells to overcome metabolic stress by inhibiting AMPK signaling, a key singular node of cellular metabolism. Recent studies have shown that AMPK signaling can also reversibly regulate hyperactive MAPK signaling in cancer cells by phosphorylating its key components, RAF/KSR family kinases, which affects not only carcinogenesis but also the outcomes of targeted cancer therapies against the MAPK signaling. In this review, we will summarize the current proceedings of how MAPK-AMPK signalings interplay with each other in cancer biology, as well as its implications in clinic cancer treatment with MAPK inhibition and AMPK modulators, and discuss the exploitation of combinatory therapies targeting both MAPK and AMPK as a novel therapeutic intervention.
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PMID:The MAPK and AMPK signalings: interplay and implication in targeted cancer therapy. 3280 25

Aging leads to and is associated with aberrant function of multiple signaling pathways and a host of factors that maintain cellular health. Under normal conditions, the prolongevity, 5' AMP-activated protein kinase (AMPK), is dedicated to the homeostasis of metabolism and autophagy for removal of damaged cellular compartments and molecules. A host of sirtuin family of molecules, that extend life-span, regulate metabolism and repair DNA damage, and possess either mono-ADP-ribosyltransferase, or deacylase activity. Another group of pro-longevity factors, include FOX (forkhead box) proteins, a family of transcription factors that regulate the expression of genes involved in cell growth, proliferation, differentiation, and longevity. Nicotinamide phosphoribosyltransferase (NAmPRTase or Nampt) catalyzes the condensation of nicotinamide with 5-phosphoribosyl-1-pyrophosphate to yield nicotinamide mononucleotide (NMN), a requisite step for production of NAD+, which is known to increase longevity. Loss of Klotho, a transmembrane enzyme that controls the sensitivity of the organism to insulin and suppresses oxidative stress and inflammation, leads to premature aging in mice. Hydrogen sulfide and transsulfuration pathways are crucial to the long life and are required in protection of cells against damage. Aging also leads to the imbalanced activation of other pathways and factors including p53, insulin and IGF signaling, P13K/AKT, mTOR, PKA, RAS, RTK, MEK, ERK, MAPK, CRTC-1/CREB and NFkB. Such aberrant cellular functions, disturb cell metabolism, derail autophagy and other housekeeping actions, inhibit cell division, induce inflammaging and immunosenecence, cause stem cell exhaustion and induce either senescence, apoptosis or cancer.
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PMID:Signaling pathways and effectors of aging. 3304 65


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