Anticancer effects of CKD-602 (Camtobell) via G2/M phase arrest in oral squamous cell carcinoma cell lines.

CKD-602 (7-[2-(N-isopropylamino) ethyl]-(20S)-camptothecin, belotecan) is a synthetic water-soluble camptothecin derivative and topoisomerase I inhibitor that has been shown to exert a clinical anticancer effect on various types of tumor. In the present study, the anticancer effects of CKD-602 on the following three human oral squamous cell carcinoma (OSCC) cell lines originating from Korean cancer patients: YD-8 (tongue), YD-9 (buccal mucosa) and YD-38 (lower gingiva) were analyzed. The apoptotic proportion of the cells and cell cycle position were analyzed using flow cytometry.

Chaperone stress 70 protein (STCH) binds and regulates two acid/base transporters NBCe1-B and NHE1.

Regulation of intracellular pH is critical for the maintenance of cell homeostasis in response to stress. We used yeast two-hybrid screening to identify novel interacting partners of the pH-regulating transporter NBCe1-B. We identified Hsp70-like stress 70 protein chaperone (STCH) as interacting with NBCe1-B at the N-terminal (amino acids 96-440) region.

Intracellular acidification is associated with changes in free cytosolic calcium and inhibition of action potentials in rat trigeminal ganglion.

The effect of intracellular acidification and subsequent pH recovery in sensory neurons has not been well characterized. We have studied the mechanisms underlying Ca(2+)-induced acidification and subsequent recovery of intracellular pH (pH(i)) in rat trigeminal ganglion neurons and report their effects on neuronal excitability. Glutamate (500 μM) and capsaicin (1 μM) increased intracellular Ca(2+) concentration ([Ca(2+)](i)) with a following decrease in pH(i).

P2X7 Receptor-mediated Membrane Blebbing in Salivary Epithelial Cells.

High concentrations of ATP induce membrane blebbing. However, the underlying mechanism involved in epithelial cells remains unclear. In this study, we investigated the role of the P2X7 receptor (P2X7R) in membrane blebbing using Par C5 cells.

Expression of the Na+-HCO3- cotransporter and its role in pHi regulation in guinea pig salivary glands.

Patterns of salivary HCO(3)(-) secretion vary and depend on species and gland types. However, the identities of the transporters involved in HCO(3)(-) transport and the underlying mechanism of intracellular pH (pH(i)) regulation in salivary glands still remain unclear. In this study, we examined the expression of the Na(+)-HCO(3)(-) cotransporter (NBC) and its role in pH(i) regulation in guinea pig salivary glands, which can serve as an experimental model to study HCO(3)(-) transport in human salivary glands.

Molecular cloning and functional expression of a sodium bicarbonate cotransporter from guinea-pig parotid glands.

We recently found that the concentration of HCO3- in guinea-pig saliva is very similar to that of human saliva; however, the entity that regulates HCO3- transport has not yet been fully characterized. In order to investigate the mechanism of HCO3- transport, we identified, cloned, and characterized a sodium bicarbonate (Na(+)/HCO3- cotransporter found in guinea-pig parotid glands (gpNBC1). The gpNBC1 gene encodes a 1079-amino acid protein that has 95% and 96% homology with human and mouse parotid NBC1, respectively.

Effects of resveratrol-related hydroxystilbenes on the nitric oxide production in macrophage cells: structural requirements and mechanism of action.

NF-kappaB that plays an important role in iNOS expression is one of the targets of various potential anti-inflammatory agents including resveratrol. Resveratrol contains a structural similarity with estrogen, and there has been speculation about resveratrol as estrogen agonist. In this study, the mechanism and structural requirements of resveratrol and related hydroxystilbenes for the inhibition of LPS-induced nitric oxide production were studied in macrophage cells (RAW 264.