Publications by authors named "Joseph Bonica"

Sphingosine kinase 1 (SK1) converts the pro-death lipid sphingosine to the pro-survival sphingosine-1-phosphate (S1P) and is upregulated in several cancers. DNA damaging agents, such as the chemotherapeutic doxorubicin (Dox), have been shown to degrade SK1 protein in cancer cells, a process dependent on wild-type p53. As mutations in p53 are very common across several types of cancer, we evaluated the effects of Dox on SK1 in p53 mutant cancer cells.

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Sphingolipids and their synthetic enzymes have emerged as critical mediators in numerous diseases including inflammation, aging, and cancer. One enzyme in particular, sphingosine kinase (SK) and its product sphingosine-1-phosphate (S1P), has been extensively implicated in these processes. SK catalyzes the phosphorylation of sphingosine to S1P and exists as two isoforms, SK1 and SK2.

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Once thought to be primarily structural in nature, sphingolipids have become increasingly appreciated as second messengers in a wide array of signaling pathways. Sphingosine kinase 1, or SK1, is one of two sphingosine kinases that phosphorylate sphingosine into sphingosine-1-phosphate (S1P). S1P is generally pro-inflammatory, pro-angiogenic, immunomodulatory, and pro-survival; therefore, high SK1 expression and activity have been associated with certain inflammatory diseases and cancer.

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Sphingosine kinase 1 (SK1) is a lipid kinase whose activity produces sphingosine 1-phosphate, a prosurvival lipid associated with proliferation, angiogenesis, and invasion. SK1 overexpression has been observed in numerous cancers. Recent studies have demonstrated that SK1 proteolysis occurs downstream of the tumor suppressor p53 in response to several DNA-damaging agents.

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Metabolic dysfunction is well-documented in Huntington's disease (HD). However, the link between the mutant huntingtin (mHTT) gene and the pathology is unknown. The tricarboxylic acid (TCA) cycle is the main metabolic pathway for the production of NADH for conversion to ATP via the electron transport chain (ETC).

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Glucose metabolism is reduced in the brains of patients with Huntington disease (HD). The mechanisms underlying this deficit, its link to the pathology of the disease, and the vulnerability of the striatum in HD remain unknown. Abnormalities in some of the key mitochondrial enzymes involved in glucose metabolism, including the pyruvate dehydrogenase complex (PDHC) and the tricarboxylic acid (TCA) cycle, may contribute to these deficits.

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