Altered survival signaling is a hallmark of malignant melanoma cells resulting in resistance to drug-induced apoptosis. Previous studies suggest that cancer cell survival depends on the modulation of cell death pathways by methylglyoxal (MG), a reactive by-product of glycolysis that acts by posttranslational modification and functional alteration of target proteins involved in cellular survival. Our preliminary data indicate that heat shock protein 27 (Hsp27) is the exclusive target of MG-adduction in human melanoma and that MG-antagonists selectively induce apoptosis and chemosensitization in human melanoma cells. In this proposal we will test the hypothesis that the glycolytic control of melanoma cell survival is mediated by MG adducted heat shock protein 27 (MG-Hsp27), a novel therapeutic target amenable to small molecule modulation by specific MG-antagonists. First, MG-Hsp27 will be characterized at the molecular, cellular, and tissue level by mapping the human melanoma MG-Hsp27 proteome (specific aim #1). The exact structure and site(s) of human melanoma Hsp27 posttranslational modification by phosphorylation and MG-adduction will be determined in melanoma cell lines and tissue. MG-Hsp27 will then be validated as a molecular target for the modulation of melanoma cell survival (specific aim #2). The molecular mechanism of survival signaling by MG-Hsp27 will be elucidated, and target validation will be achieved by metabolic, pharmacological, and genetic modulation of MG-Hsp27. Next, cell-based screening of small molecule MG antagonists for potency of target modulation and anti-melanoma activity will identify a lead series of bioactive MG-Hsp27-inhibitors (specific aim #3). Finally, proof-of-principle evidence for chemotherapeutic potential of MG-antagonists will be tested in a xenograft mouse melanoma model using MG-antagonists as single agents or in combination with other chemotherapeutic agents (specific aim #4). Successful completion of the proposed research will identify a unique metabolic vulnerability of cancer cells that can be attacked by small molecule antagonists. Lay description: Melanoma, a highly aggressive tumor that originates from pigment producing cells in human skin, has an increasing incidence that currently surpasses that of any other cancer. My recent research suggests that a byproduct of sugar energy metabolism called methylglyoxal may represent an Achilles heel of human melanoma cells. The proposed research aims to elucidate the molecular mechanism that regulates melanoma cell survival by methylglyoxal and to test antagonists of methylglyoxal as novel anti-melanoma therapeutics.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
3R01CA122484-03S1
Application #
7919126
Study Section
Basic Mechanisms of Cancer Therapeutics Study Section (BMCT)
Program Officer
Forry, Suzanne L
Project Start
2009-08-01
Project End
2011-07-31
Budget Start
2009-08-01
Budget End
2011-07-31
Support Year
3
Fiscal Year
2009
Total Cost
$175,489
Indirect Cost
Name
University of Arizona
Department
Pharmacology
Type
Schools of Pharmacy
DUNS #
806345617
City
Tucson
State
AZ
Country
United States
Zip Code
85721
Davis, Angela L; Qiao, Shuxi; Lesson, Jessica L et al. (2015) The quinone methide aurin is a heat shock response inducer that causes proteotoxic stress and Noxa-dependent apoptosis in malignant melanoma cells. J Biol Chem 290:1623-38
Park, Sophia L; Justiniano, Rebecca; Williams, Joshua D et al. (2015) The Tryptophan-Derived Endogenous Aryl Hydrocarbon Receptor Ligand 6-Formylindolo[3,2-b]Carbazole Is a Nanomolar UVA Photosensitizer in Epidermal Keratinocytes. J Invest Dermatol 135:1649-1658
Davis, Angela L; Cabello, Christopher M; Qiao, Shuxi et al. (2013) Phenotypic identification of the redox dye methylene blue as an antagonist of heat shock response gene expression in metastatic melanoma cells. Int J Mol Sci 14:4185-202
Qiao, Shuxi; Tao, Shasha; Rojo de la Vega, Montserrat et al. (2013) The antimalarial amodiaquine causes autophagic-lysosomal and proliferative blockade sensitizing human melanoma cells to starvation- and chemotherapy-induced cell death. Autophagy 9:2087-102
Lamore, Sarah D; Wondrak, Georg T (2013) UVA causes dual inactivation of cathepsin B and L underlying lysosomal dysfunction in human dermal fibroblasts. J Photochem Photobiol B 123:1-12
Tao, Shasha; Justiniano, Rebecca; Zhang, Donna D et al. (2013) The Nrf2-inducers tanshinone I and dihydrotanshinone protect human skin cells and reconstructed human skin against solar simulated UV. Redox Biol 1:532-41
Cabello, Christopher M; Lamore, Sarah D; Bair 3rd, Warner B et al. (2012) The redox antimalarial dihydroartemisinin targets human metastatic melanoma cells but not primary melanocytes with induction of NOXA-dependent apoptosis. Invest New Drugs 30:1289-301
Qiao, Shuxi; Lamore, Sarah D; Cabello, Christopher M et al. (2012) Thiostrepton is an inducer of oxidative and proteotoxic stress that impairs viability of human melanoma cells but not primary melanocytes. Biochem Pharmacol 83:1229-40
Lamore, Sarah D; Wondrak, Georg T (2012) Autophagic-lysosomal dysregulation downstream of cathepsin B inactivation in human skin fibroblasts exposed to UVA. Photochem Photobiol Sci 11:163-72
Qiao, Shuxi; Cabello, Christopher M; Lamore, Sarah D et al. (2012) D-Penicillamine targets metastatic melanoma cells with induction of the unfolded protein response (UPR) and Noxa (PMAIP1)-dependent mitochondrial apoptosis. Apoptosis 17:1079-94

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