Regulates CDC25A expression by inhibiting the biogenesis of let-7 miRNA which negatively regulates

Adipose tissue is central to lipid regulation, facilitating both the storage of fatty acids as neutral lipids within the lipid droplets of adipocytes, and regulating the release of fatty acids in response to both acute and DAPT chronic stimuli. In metabolic disorders these essential functions of adipose tissue are compromised. Determining the cellular mechanisms underlying the dysregulation of adipocytes is fundamentally important to understanding adipose tissue regulation and metabolism. The mobilization of fatty acids from adipose tissue in vivo is regulated by specific mechanisms. Catecholamines acutely stimulate lipolysis through the activation of betaadrenergic receptors at the adipocyte cell surface. This results in the activation of a well characterized cAMPdependent, G-protein coupled signal transduction cascade culminating with the phosphorylation and activation of proteins at the surface of LDs by protein kinase A, including the major structural protein in the adipocyte LD, perilipin A, and the primary diacylglycerol lipase, hormone-sensitive lipase. During fasting the mobilization of fatty acids can be chronically activated through a combination of increased adrenaline and glucagon and reduced levels of insulin. In addition cytokines such as tumor necrosis factor and interleukin-6 have also been shown to promote lipolysis both in vitro and in vivo. Together these data suggest that CAV1 and caveolae play pleiotropic roles in adipose tissue regulation and function. These roles are likely to include general regulatory mechanisms such as signaling and lipid transfer, together with context specific roles related to the adipose tissue microenvironment or specific metabolic challenges. Non-Small cell Lung Cancer is the most common type of lung cancer and is a result of accumulated molecular alterations leading to deregulation of several cellular processes including cell cycle control. In NSCLC, several cell-cycle regulators that play a critical role in cell cycle check point controls are altered, which allows the cancer cells bypass different checkpoints, especially at G1/S and G2/M with subsequent uncontrolled cellular proliferation. Cell division cycle 25A is a member of the CDC25 family of dual specific phosphatases and plays a critical role in cell cycle progression. CDC25A functions to remove the inhibitory phosphates from threonine and tyrosine residues in the ATP-binding sites of CDKs, promoting cell cycle progression. CDC25A is also a downstream target of Chk1-mediated checkpoint pathway: activation of Chk1 by DNA damaging conditions targets CDC25A for proteasome degradation, which prevents cells with chromosomal abnormalities from progressing through the cell cycle. While CDK1 plays a critical role for CDC25A stabilization during mitosis. CDC25A is frequently overexpressed in cancers including NSCLC. This overexpression is associated with a more aggressive clinical behavior and inferior survival. Though CDC25A has been extensively studied for its role in tumor progression and as a potential target for cancer treatment, the mechanisms of CDC25A overexpression in cancer remains to be investigated. Some studies have shown that overexpression of CDC25A in cancers could result from post-transcriptional deregulations such as overexpression of DUB3 ubiquitin hydrolase, inactivation of glycogen synthase kinase-3beta, which phosphorylates CDC25A to promote its proteolysis in early cellcycle phases.

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