Previous studies suggest that endothelial progenitor cells (EPCs) contribute to vascular repair processes. In contrast, circulating microparticles (MPs) are reported to be part of a process that is damaging to vascular cells. Numerous studies suggest that the "balance" between EPCs and MPs is important for the integrity of vascular cells and preservation of endothelial function. In the present study, we assess the impact of acetylsalicylate (ASA) - which is, beside statins and physical exercise, a third basic column in the preventive therapy of coronary artery disease (CAD) - on EPCs and MPs in patients with CAD. We investigated the effect of treatment (8 weeks) with ASA (100 mg/d) on endothelial function (flow-mediated vasodilation, FMD), number of circulating EPCs, and endothelial- and platelet-derived microparticles (eMP, pMP) in 15 male patients (age 59.5 ± 12.3 years) with CAD but nonsignificant stenosis. The number of pMPs and eMPs decreased by 62.7% (p < 0.05) and 28.4% (p < 0.05), respectively. The number of circulating EPCs (VEGFR2(+)CD34(+)), expressed as ‰ of circulating polymorphonuclear leukocytes, remained unchanged. Despite the reduced number of pMPs and eMPs in response to the ASA therapy, the FMD responses and the maximal dilator effects of nitroglycerin were unaffected. In a control experiment, patients (n = 6) treated with the selective COX-2 inhibitor etoricoxib (90 mg/day) for 8 weeks showed no changes in the number of pMPs, eMPs, and EPCs and in FMD. We report on a novel effect of ASA treatment on the number of circulating endothelial- and platelet-derived microparticles in patients with cardiovascular disease. The mechanism remains elusive, and appears not to be associated with the COX-2 pathway.

Abstract. The treatment of choice for esophageal cancer is considered surgical resection, but a median survival of around 20 months after treatment is still discouraging. The value of adjuvant or neoadjuvant radiation or chemotherapy is limited and to date, benefits have only been described for certain tumor stages. Therefore, new therapeutic options are required. As alternative chemotherapeutics, we tested the antibiotic taurolidine (TRD) on KYSE 270 human esophageal carcinoma cells alone and in combination with rhTRAIL (TNF related apoptosis-inducing ligand). Viability, apoptosis and necrosis were visualized by TUNEL assay and quantitated by FACS analysis. Gene expression was analysed by RNA microarray. The most effective concentration of TRD as single substance (250 μmol/l) induced apoptosis to a maximum of 40% after 12-h dose dependently, leaving 4% viable cells after 48 h; by comparison, rhTRAIL did not have a significant effect. The combination of both substances doubled the effect of TRD alone. Gene expression profiling revealed that TRD downregulated endogenous TRAIL, TNFRSF1A, TRADD, TNFRSF1B, TNFRSF21, FADD, as well as MAP2K4, JAK2 and Bcl2, Bcl2l1, APAF1 and caspase-3. TNFRSF25, cytochrome-c, caspase-1, -8, -9, JUN, GADD45A and NFKBIA were upregulated. TRAIL reduced endogenous TRAIL, Bcl2l1 and caspase-1 expression. BIRC2, BIRC3, TNFAIP3, and NFKBIA were upregulated. The combined substances upregulated endogenous TRAIL, NFKBIA and JUN, whereas DFFA and TRAF3 were downregulated compared to TRD as single substance. We conclude that TRD overcomes TRAIL resistance in KYSE 270 cells. Synergistic effects are dependent on the same and on distinct apoptotic pathways which, jointly triggered, result in an amplified response. Several apoptotic pathways, including the TNF-receptor associated and the mitochondrial pathway, were differentially regulated by the substances on gene expression level. Additionally transcription factors seem to be influenced, NFKB in particular. Endogenous TRAIL expression is increased by the combination of substances, whereas it is reduced by each single substance. Taking into consideration that the non-toxic TRD was able to reduce rhTRAIL toxicity and dose, combined therapy with TRD and rhTRAIL may offer new options for treatment in esophageal cancer.

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COX-2 inhibition with the prodrug, parecoxib, diminishes the acetylcholine-induced vasodilatation in the forearm circulation of patients with essential hypertension. It is speculated that the production of vasodilator prostaglandins may be important in pathological states with endothelial dysfunction, at least in patients with essential hypertension.