['Our previous studies revealed upregulation of stanniocalcin-1 (STC1) in cardiac vessels in dilated cardiomyopathy. However, the functional significance of STC1 is unknown. The objective of this study was to determine the effects of STC1 on TNF-alpha-induced monolayer permeability of human coronary artery endothelial cells (HCAECs).', 'Cells were pretreated with STC1 for 30 minutes followed by treatment with TNF-alpha (2 ng/mL) for 24 hours. Monolayer permeability was studied using a transwell system. STC1 pretreatment significantly blocked TNF-alpha-induced monolayer permeability in a concentration- and time-dependent manner. STC1 effectively blocked TNF-alpha-induced downregulation of endothelial tight junction proteins zonula occluden-1 and claudin-1 at both mRNA and protein levels. STC1 also significantly decreased TNF-alpha-induced superoxide anion production. The inhibitory effect of STC1 was specific to TNF-alpha, as it failed to inhibit VEGF-induced endothelial permeability. Furthermore, STC1 partially blocked NF-kappaB and JNK activation in TNF-alpha-treated endothelial cells. JNK inhibitor and antioxidant also effectively blocked TNF-alpha-induced NF-kappaB activation and monolayer permeability in HCAECs.'] Does human stanniocalcin-1 block TNF-alpha-induced monolayer permeability in human coronary artery endothelial cells?