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Runt-related transcription factor 1 (RUNX1) is essential for the establishment of fetal and adult hematopoiesis and neuronal development. Aberrant expression of RUNX1 led to proliferation and metastasis of several cancers. The aim of the present study was to investigate the role of RUNX1 in migration, invasion, and angiogenesis of human glioblastoma using IL-1β-treated U-87 MG human glioblastoma cells as a model. IL-1β at 10 ng/ml stimulated translocation of RUNX1 into the nucleus with increased expressions of RUNX1, MMP-1, MMP-2, MMP-9, MMP-19, and VEGFA in U-87 MG cells. In addition, silencing of RUNX1 gene significantly suppressed U-87 MG cell migration and invasion abilities. Moreover, knockdown of RUNX1 mRNA in U-87 MG cells reduced the tube formation of human umbilical vein endothelial cells. Further investigation revealed that IL-1β-induced RUNX1 expression might be mediated via the p38 mitogen-activated protein kinase (MAPK) signaling molecule for the expression of these invasion- and angiogenic-related molecules. Together with an inhibitor of p38 MAPK (SB203580) could decrease RUNX1 mRNA expression. Thus, RUNX1 may be one of the putative molecular targeted therapies against glioma metastasis and angiogenesis through the activation of p38 MAPK signaling pathway.

In molluscs, the neurotransmitter serotonin (5-HT) has been linked to a variety of biological roles including gamete maturation and spawning. The possible involvement of 5-HT in abalone gamete release was demonstrated by a dose-dependent increase in Haliotis rubra gonad contractile bioactivity following 5-HT stimulation. Physiological functions associated with 5-HT, are mediated through binding to 5-HT receptors. A cDNA encoding a putative 5-HT receptor consisting of 359 amino acids was isolated from the tropical abalone H. asinina, termed 5-HT(1 ha). The 5-HT(1 ha) shares G-protein-coupled receptor motifs with metazoan 5-HT receptors, including predicted transmembrane domains, active sites for protein kinase action, and N-linked glycosylation sites. However, the third intracellular loop of 5-HT(1 ha) is relatively short, and only six transmembrane domains are predicted, implying a truncated receptor. Phylogenetic analysis with known 5-HT receptor genes suggests that 5-HT(1 ha) belongs to the type 1 5-HT receptor family. Expression analysis by RT-PCR showed that 5-HT(1 ha) mRNA was present in all tissues examined, including the neural ganglia and gonad tissues. Immunocytochemistry revealed the presence of 5-HT(1 ha) specifically within the soma of neuronal cells located in the outer cortex of both cerebral and pleuropedal ganglia. In ovarian and testicular tissues, 5-HT(1 ha) immunoreactivity was observed in epithelial cells of the outer capsule and connective tissue of the trabeculae to which the gamete follicles adhere. Whether this receptor transcript is translated to a functional protein needs to be verified, but if so, it could play a role in reproduction.