Ophiopogonin D (OPD) is a steroidal glycoside derived from Ophiopogon japonicus , a traditional Chinese medicine with diverse biological activities, including antithrombosis, anti-inflammation, and antitussive effects. To investigate the cellular effects and mechanisms of OPD on oral squamous cell carcinoma, cell viability was explored, and the effects of OPD on cell cycle regulators, apoptotic marker proteins, and key proteins involved in metastasis and signaling pathways were examined by MTT assay and Western blotting in YD38 cells. OPD strongly inhibited cell proliferation and induced caspase-dependent apoptosis of YD38 cells by suppressing the cell cycle and activating caspase-3 and poly ADP ribose polymerase. Additionally, OPD suppressed the expression of vital proteins regulating metastasis and proliferation within the integrin/matrix metalloproteinases/FAK and AKT/PI3K/mTor pathways. Thus, OPD can be a potential treatment candidate for gingival cancer.

Associations between periodontal infection and cardiovascular disease have been documented. Porphyromonas gingivalis is a well-established periodontal pathogen, and tissue factor (TF) is a key initiator of the coagulation cascade. In this context, P. gingivalis has been reported to enhance TF expression in human endothelial cells. The present study investigated the underlying mechanisms of TF induction by P. gingivalis in human umbilical vein endothelial cells. P. gingivalis increased TF expression in a dose- and time-dependent manner. Not only live bacteria but also glutaraldehyde-fixed bacteria increased TF expression to the same extent. However, sonicates of P. gingivalis did not induce TF expression. Cytochalasin D and SMIFH2, which are inhibitors of actin polymerization and actin nucleation, respectively, inhibited the TF expression induced by P. gingivalis . Finally, TF production was decreased or increased in the presence of various signaling inhibitors, including mitogen-activated protein kinases. These results suggest that P. gingivalis induces endothelial TF expression by a bacterial internalization-dependent mechanism and through diverse signal transduction mechanisms.

In the present study, rutile phase titanium dioxide nanoparticles (R-TiO2 NPs) were prepared by hydrolysis of titanium tetrachloride in an aqueous solution followed by calcination at 900℃. The composition of R-TiO2 NPs was determined by the analysis of X-ray diffraction data, and the characteristic features of R-TiO2 NPs such as the surface functional group, particle size, shape, surface topography, and morphological behavior were analyzed by Fourier-transform infrared spectroscopy, scanning electron microscopy and energy dispersive X-ray spectroscopy, transmission electron microscopy, dynamic light scattering, and zeta potential measurements. The average size of the prepared R-TiO2 NPs was 76 nm, the surface area was 19 m2/g, zeta potential was −20.8 mV, and average hydrodynamic diameter in dimethyl sulfoxide (DMSO)–H2O solution was 550 nm. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and morphological observations revealed that R-TiO2 NPs were cytocompatible with oral cancer cells, with no inhibition of cell growth and proliferation. This suggests the efficacy of R-TiO2 NPs for the aesthetic white pigmentation of teeth.