Thioredoxin family members involved in cellular protein signaling networks provide an important mechanism regulating many aspects of cell function including proliferation and cell survival. Redox signaling involves a protein post translational modification second in importance only to protein phosphorylation. Unlike protein phosphorylation little is known of redox signaling networks in the cell or how they are altered in cancer. The increased expression of one redox signaling protein in particular thioredoxin-1 (Trx-1) has been associated with aggressive tumor growth, decreased apoptotic cell death and decreased patient survival. The hypothesis upon which our studies are based is that redox signaling through thioredoxin family members is an important signaling mechanism that is deranged in cancer and that understanding redox signaling networks in the cancer cell will allow the identification of novel molecular targets for cancer drug discovery and development, and new strategies to treat cancer. We have used Drosophila genetics together with functional genetic siRNA studies in human cancer cells to identify new redox signaling pathways which we will investigate in human cancer cells. We will also investigate the redox regulation of the unfolded protein response (UPR) which is important for maintaining the synthesis of cell survival proteins during stress, including many angiogenic factors important in cancer. We will conduct in vivo antitumor and mechanistic studies of an inhibitor of Trx-1 in colorectal cancer and of a new antitumor inhibitor of thioredoxin reductase we have developed. The overall objective of our studies is to use redox signaling pathways in cancer to identify new molecular targets for cancer drug discovery and development, and to provide new strategies to treat cancer. The work builds upon our past studies of Trx-1 as a cancer drug target which has led to the development of one cancer drug in clinical trial, and seeks to identify new pathways of redox signaling by thioredoxin family members for the identification of molecular targets for cancer drug discovery.
We propose that altered oxidation (redox) states of key cellular proteins that provide growth signals to cancer cells is responsible for their unregulated growth. The studies are designed to identify new redox pathways based on results of genetic studies in flies, studies of the effects of human genes on the pathways and the effects of redox stress on cancer cell growth. The role of the pathways in human cancer will be confirmed to allow the identification of new molecular targets for cancer drug discovery and new strategies to treat cancer.
|Guntle, Gerald P; Jagadish, Bhumasamudram; Mash, Eugene A et al. (2012) Tumor Xenograft Response to Redox-Active Therapies Assessed by Magnetic Resonance Imaging Using a Thiol-Bearing DOTA Complex of Gadolinium. Transl Oncol 5:190-9|
|Sheveleva, Elena V; Landowski, Terry H; Samulitis, Betty K et al. (2012) Imexon induces an oxidative endoplasmic reticulum stress response in pancreatic cancer cells. Mol Cancer Res 10:392-400|
|Kim, Yon Hui; Coon, Amy; Baker, Amanda F et al. (2011) Antitumor agent PX-12 inhibits HIF-1ýý protein levels through an Nrf2/PMF-1-mediated increase in spermidine/spermine acetyl transferase. Cancer Chemother Pharmacol 68:405-13|
|James, Brian P; Staatz, William D; Wilkinson, Sarah T et al. (2009) Superoxide dismutase is regulated by LAMMER kinase in Drosophila and human cells. Free Radic Biol Med 46:821-7|
|Bartholomeusz, Geoffrey; Cherukuri, Paul; Kingston, John et al. (2009) In Vivo Therapeutic Silencing of Hypoxia-Inducible Factor 1 Alpha (HIF-1?) Using Single-Walled Carbon Nanotubes Noncovalently Coated with siRNA. Nano Res 2:279-291|
|Baker, Amanda F; Koh, Mei Y; Williams, Ryan R et al. (2008) Identification of thioredoxin-interacting protein 1 as a hypoxia-inducible factor 1alpha-induced gene in pancreatic cancer. Pancreas 36:178-86|
|Koh, Mei Y; Spivak-Kroizman, Taly; Venturini, Sara et al. (2008) Molecular mechanisms for the activity of PX-478, an antitumor inhibitor of the hypoxia-inducible factor-1alpha. Mol Cancer Ther 7:90-100|
|Powis, Garth; Kirkpatrick, D Lynn (2007) Thioredoxin signaling as a target for cancer therapy. Curr Opin Pharmacol 7:392-7|
|Baker, Amanda F; Dragovich, Tomislav; Tate, Wendy R et al. (2006) The antitumor thioredoxin-1 inhibitor PX-12 (1-methylpropyl 2-imidazolyl disulfide) decreases thioredoxin-1 and VEGF levels in cancer patient plasma. J Lab Clin Med 147:83-90|
|Engman, Lars; McNaughton, Michael; Gajewska, Malgorzata et al. (2006) Thioredoxin reductase and cancer cell growth inhibition by organogold(III) compounds. Anticancer Drugs 17:539-44|
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