This study examined the notion that exogenous generation of nitric oxide (NO) modulates NOS gene expression and activity. Bovine pulmonary artery endothelial cells (BPAEC) were treated with the NO donors, 1 mM SNAP (S-nitroso-N-acetylpenicillamine), 0.5 mM SNP (sodium nitroprusside) or 0.2 microM NONOate (spermine NONOate) in medium 199 containing 2% FBS. Controls included untreated cells and cells exposed to 1 mM NAP (N-acetyl-D-penicillamine). NOS activity was assessed using a fibroblast-reporter cell assay; intracellular Ca2+ concentrations were assessed by Fura-2 microfluorometry; and NO release was measured by chemiluminescence. Constitutive endothelial (e) and inducible (i) NOS gene and protein expression were examined by northern and western blot analysis, respectively. Two hours exposure to either SNAP or NONOate caused a significant elevation in NO release from the endothelial cells (SNAP = 51.4 +/- 5.9; NONOate = 23.8 +/- 4.2; control = 14.5 +/- 2.8 microM); but A23187 (3 microM)-stimulated NO release was attenuated when compared to controls. Treatment with either SNAP or NONOate for 2 h also resulted in a significant increase in NOS activity in endothelial homogenates (SNAP = 23.6 +/- 2.5; NONOate= 29.8 +/- 7.7; control = 14.5 +/- 2.5fmol cGMP/microg per 10(6) cells). Exposure to SNAP and SNP, but not NONOate, for 1 h caused an increase in intracellular calcium. Between 4 and 8 h, SNAP and NONOate caused a 2- to 3-fold increase in eNOS, but not iNOS, gene (P < 0.05) and protein expression. NAP had little effect on either eNOS gene expression, activity or NO production. Our data indicate that exogenous generation of NO leads to a biphasic response in BPAEC, an early increase in intracellular Ca2+, and increases in NOS activity and NO release followed by increased expression of the eNOS gene, but not the iNOS gene. We conclude that eNOS gene expression and activity are regulated by a positive-feedback regulatory action of exogenous NO.

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9 Background: Active surveillance (AS - serial follow-up PSA, exam, and biopsy) is an option for men with early stage, low risk prostate cancer (LRPca). While data show comparable survival for AS vs active treatment (AT - surgery or radiation), currently most men with LRPca undergo AT. A pilot Decision Counseling Program (DCP) to assist men in making an informed, shared LRPca treatment decision was implemented. Methods: Men with LRPca seen at the Jefferson Genitourinary Multidisciplinary Cancer Center (JGUMDCC) were consented. A nurse educator (NE) reviewed risks/benefits of AS and AT; had the participant identify factors influencing treatment decision making and specify decision factor weights; entered data into an online DCP; and generated a report of participant treatment preference and decision factors. The report was used by the participant and clinicians in shared treatment decision making. A follow-up survey was administered 30 days after the visit, with treatment status assessed. Change in treatment-related knowledge and decisional conflict were measured using baseline and 30-day survey data. Results: Baseline decision counseling preference of 16 participants: 4 - AS, 8 equal for AS and AT, 4 - AT. At 30 days, 12 participants initiated AS, 4 chose AT; participant mean treatment knowledge scores (8-point scale) increased (+1.13 points); decisional conflict subscale scores (strongly disagree = 1, strongly agree = 5) decreased (uncertain: -1.15, uninformed: -1.36, unclear: -1.12; and unsupported: -1.15). Conclusions: Decision counseling and shared decision making helped participants become better informed about treatment choices and reduced uncertainty in treatment decision making. The combined intervention resulted in most participants choosing AS. Ongoing study recruitment, data collection, and analyses are planned.