Plasminogen activator inhibitor-1 as regulator of tumor-initiating cell properties in head and neck cancers.

Background: The existence of tumor-initiating cells (TICs) has been described in head and neck cancers. Plasminogen activator inhibitor-1 (PAI-1) has been demonstrated to act as a prognostic factor in head and neck cancers.

Methods: Tiplaxtinin (PAI-039), a specific inhibitor of PAI-1, and PAI-1-specific siRNA were used to examine the role of PAI-1 in the self-renewal property of head and neck cancer-TICs by tumorsphere formation.

Quercetin in elimination of tumor initiating stem-like and mesenchymal transformation property in head and neck cancer.

Background: Previously, we enriched a subpopulation of head and neck cancer-derived tumor initiating cells (HNC-TICs) presented high tumorigenic, chemo-radioresistant, and coupled with epithelial-mesenchymal transition (EMT) properties. The purpose of this study was to investigate the therapeutic effect and molecular mechanisms of quercetin on HNC-TICs.

Method: ALDH1 activity of head and neck cancer cells with quercetin treatment was assessed by the Aldefluor assay flow cytometry analysis.

Effect of hexasulfobutylated C(60) on the isolated aortic ring of guinea pig.

The effects of hexasulfobutylated C(60) (FC(4)S) and monomalonic acid C(60) (MMA C(60)), the fullerene C(60) derivatives, on isolated endothelium-containing or endothelium-denuded aorta of guinea pig were studied pharmacologically in vitro. In the endothelium-containing preparation of the aortic rings, phenylephrine (PHE) elicited contracture and acetylcholine (ACh) elicited a relaxing effect on the PHE-precontracted preparation. In the PHE-precontracted preparation, MMA C(60) (10 micromol/l) did not elicit a relaxing effect on the PHE-precontracted preparation.