Our research is focused on understanding cellular and molecular mechanisms of growth factor mediated signal transduction in tumor cells. Of particular interest to the laboratory are the receptors for epidermal growth factor (EGF), platelet activating factor (PAF), and gamma interferon. Efforts are in progress to identify transcription factors that are tyrosine phosphorylated by these receptors. Another important area of study in the laboratory is centered on the recently discovered signalling molecule, nitric oxide. Important in cell-cell signalling in a variety of physiological processes, efforts are underway to understand the mechanisms regulating its production by mammalian cells. Growth factors have been identified as a major regulator of nitric oxide production. The role of nitric in cellular nitric oxide production are under investigation. The laboratory has discovered that the bone marrow has the capacity to produce large amounts of nitric oxide in response to inflammatory mediators and several bone marrow growth factors including macrophage colony stimulating factor, interleukin-3 and granulocyte-macrophage colony stimulating factor. These cytokines are used clinically to stimulate immune cell development in the bone marrow in cancer and transplantation patients. Nitric oxide production reduces bone marrow cell growth and antagonizes the effectiveness of these colony stimulating factors. Identifying the bone marrow cell populations producing nitric oxide and the mechanisms by which the cytokine receptors are coupled to the nitric oxide synthetic machinery within these cells are major questions currently being addressed in the laboratory.

	Ozone-induced production of nitric oxide and TNF-alpha and tissue injury are dependent on NF-kappaB p50. Fakhrzadeh L, Laskin JD, Laskin DL. Am J Physiol Lung Cell Mol Physiol. 2004 Aug;287(2):L279-85. Epub 2004 Apr 02.
	Solar ultraviolet radiation as a trigger of cell signal transduction. Heck DE, Gerecke DR, Vetrano AM, Laskin JD. Toxicol Appl Pharmacol. 2004 Mar 15;195(3):288-97.
	Role of tumor necrosis factor receptor 1 (p55) in hepatocyte proliferation during acetaminophen-induced toxicity in mice. Chiu H, Gardner CR, Dambach DM, Durham SK, Brittingham JA, Laskin JD, Laskin DL. Toxicol Appl Pharmacol. 2003 Dec 1;193(2):218-27.
	Ryanodine-sensitive calcium flux regulates motility of Arbacia punctulata sperm. Heck DE, Laskin JD. Biol Bull. 2003 Oct;205(2):185-6.