Funding is requested to support our ongoing studies toward identification of molecular mechanisms mediating oncogenic effects of tobacco nitrosamines on respiratory cells and development of novel anti-cancer therapies using nicotinic acetylcholine receptor (nAChR) ligands. Preliminary studies revealed an anti-tumor potential of both canonical and non-canonical ligands of the nAChRs expressed on the cell membrane of respiratory cells. These receptors play a role in the malignant transformation of BEP2D cells caused by pharmacologic doses of the tobacco-derived carcinogenic nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). The NNK-transformed and lung cancer cells are highly sensitive to apoptosis induced by the novel cholinergic peptide SLURP-1 (secreted mammalian Ly-6/urokinase plasminogen activator receptor [uPAR]-related protein). Integrating structural and functional information about SLURP-1 vs. NNK actions on respiratory cells will facilitate a better understanding of the physiologic mechanism of tumor surveillance in lungs, and may lead to the development of novel methods of prevention and treatments of tobacco-related lung cancer. We will test the following working hypotheses: 1) SLURP-1 can prevent NNK-dependent transformation of respiratory cells in vitro and in vivo;2) cytoplasmic trapping of SLURP-1 results in altered expression of nAChRs on the plasma membrane of NNK-transformed BEP2D and lung cancer cells;3) SLURP-1 acts as a competitive nAChR antagonist with the 17 nAChR subtype mediating most of SLURP-1 effects;and 4) SLURP-1 interferes with the receptor-mediated signaling downstream of the nAChR subtype(s) ligated by NNK in normal and malignant human respiratory cells.
The Specific Aims will be to determine: 1) the role of SLURP-1 in the physiologic protection of respiratory cells from NNK carcinogenicity;2) the molecular mechanism of increased sensitivity of malignant respiratory cells to the apoptosis induced by SLURP-1;3) the nAChR subtype(s) mediating the pharmacologic activity of SLURP-1 and the mode of its action on the nAChRs expressed by respiratory cells;and 4) the signaling pathways downstream of the nAChRs ligated by SLURP-1 and NNK.

Public Health Relevance

This proposal is focused on urgent problems of prevention and treatment of tobacco related lung cancer. It further develops a novel concept of receptor-mediated action of tobacco carcinogens and tumor promoters placing lung nicotinic acetylcholine receptors in the center of the pathophysiologic loop. The long-term objective is to develop pharmacologic chemoprevention of lung cancer in former smokers, and in people exposed to environmental tobacco smoke. The projected studies will ultimately establish the mechanism of anti-tumor activity of SLURP-1-an efficient, yet previously unknown, autocrine and paracrine ligand of lung nicotinic receptors capable of preventing tobacco nitrosamine-induced malignant transformation of BEP2D cells.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Project (R01)
Project #
5R01ES017009-04
Application #
8417010
Study Section
Cancer Etiology Study Section (CE)
Program Officer
Nadadur, Srikanth
Project Start
2010-05-01
Project End
2015-01-31
Budget Start
2013-02-01
Budget End
2014-01-31
Support Year
4
Fiscal Year
2013
Total Cost
$333,991
Indirect Cost
$115,696
Name
University of California Irvine
Department
Dermatology
Type
Schools of Medicine
DUNS #
046705849
City
Irvine
State
CA
Country
United States
Zip Code
92697
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Gordon, William; Galitovskiy, Valentin; Edwards, Robert et al. (2013) The tobacco carcinogen nitrosamine induces a differential gene expression response in tumour susceptible A/J and resistant C3H mouse lungs. Eur J Cancer 49:725-33
Galitovskiy, Valentin; Chernyavsky, Alexander I; Edwards, Robert A et al. (2012) Muscle sarcomas and alopecia in A/J mice chronically treated with nicotine. Life Sci 91:1109-12
Chikova, Anna; Grando, Sergei A (2011) Naturally occurring variants of human ?9 nicotinic receptor differentially affect bronchial cell proliferation and transformation. PLoS One 6:e27978
Chernyavsky, Alexander I; Arredondo, Juan; Galitovskiy, Valentin et al. (2010) Upregulation of nuclear factor-kappaB expression by SLURP-1 is mediated by alpha7-nicotinic acetylcholine receptor and involves both ionic events and activation of protein kinases. Am J Physiol Cell Physiol 299:C903-11