Runt-related gene 2 is involved in the inhibition of matrix metalloproteinase-13 expression by roxithromycin in human gingival epithelial cell cultures.

BACKGROUND AND OBJECTIVE: Matrix metalloproteinase (MMP)-13 has wide substrate specificity compared with other MMPs and appears to be involved in periodontitis. Previously, we reported that roxithromycin (RXM) inhibits vascular endothelial growth factor expression induced by tumour necrosis factor-alpha in human periodontal ligament cells, but little is known about the effect of RXM on MMP-13 expression in human gingival epithelial cells. We therefore examined the effect of RXM on MMP-13 mRNA expression and production in cultured human gingival epithelial cells. MATERIAL AND METHODS: Human epithelial cell lines (Ca9-22, TU4, SCCTF and HSC-3) were plated in tissue culture dishes. Then, the culture supernatants and sediments were collected and the production of MMP-13 was analysed using enzyme-linked immunosorbent assay; the expression of MMP-13 mRNA and runt-related gene 2 mRNA was assessed using reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time RT-PCR. We also studied the effect of Runx2 short interfering RNA (siRNA) on the induction of MMP-13. RESULTS: Roxithromycin downregulated the induction of MMP-13 in Ca9-22 cells. Roxithromycin suppressed the expression of MMP-13 mRNA not only in Ca9-22 cells, but also in other human epithelial cell lines. Roxithromycin strongly inhibited the expression of Runx2 mRNA. Furthermore, Runx2 siRNA inhibited the induction of MMP-13 in Ca9-22 cells. CONCLUSION: These results indicate that RXM suppresses MMP-13 via the downregulation of Runx2 in human gingival epithelial cell cultures.

Roxithromycin inhibits constitutive activation of nuclear factor {kappa}B by diminishing oxidative stress in a rat model of hepatocellular carcinoma.

PURPOSE: Recently, 14-member macrolide antibiotics such as clarithromycin and roxithromycin have been shown to have anticancer and antiangiogenic effects. We investigated the suppressive effect of roxithromycin on accelerated hepatocellular carcinoma growth in a rat hepatocarcinogenetic model and compared results with effects from TNP-470. EXPERIMENTAL DESIGN: Tumor was induced by oral diethylnitrosamine administration for 17 weeks. Normal saline, TNP-470 (50 mg/kg), or roxithromycin (40 or 100 mg/kg) was administered i.p. thrice per week from week 10 to 17. RESULTS: Carcinomatous tissue growing outside dysplastic nodules and a marked expression of placental glutathione S-transferase were detected in rats with induced carcinogenesis. Tumor growth was accompanied by augmented expression of inducible nitric oxide synthase, activation of nuclear factor kappaB, and increased lipid peroxidation level. All these effects were absent in animals that received roxithromycin or TNP-470. The inhibitory effect of roxithromycin was dose dependent and no clear differences were noted between groups given roxithromycin 100 mg/kg and TNP-470 50 mg/kg. CONCLUSIONS: Our results indicate that roxithromycin inhibits oxidative stress, nitric oxide production, and nuclear factor kappaB activation induced by experimental hepatocarcinogenesis. The data provide additional evidence for the potential use of roxithromycin in treatment of hepatocellular carcinoma prevention.

Roxithromycin inhibits angiogenesis of human hepatoma cells in vivo by suppressing VEGF production.

BACKGROUND: Recently, 14-member macrolide antibiotics such as Clarithromycin and Roxithromycin (RXM) have been shown to have anti-cancer and anti-angiogeneic effects. However, it is not fully understood whether and how RXM suppresses angiogenesis in human hepatoma, which is a well-known hypervascular tumor. MATERIALS AND METHODS: In the present study, we examined the effects of RXM on tumor angiogenesis in the human hepatoma cell line, HepG2. In vivo, angiogenesis was examined using a mouse dorsal air sac model. RESULTS: The inhibitory effect of RXM was dose-dependent and the angiogenesis index of 100mg/kg/day of RXM administered intraperitoneally twice a day was significantly lower than the control. Next, we examined the effect of RXM on vascular endothelial growth factor (VEGF) mRNA expression and its protein level in HepG2 cells. When 100 microM of RXM were added, VEGF mRNA expression in HepG cells was inhibited and its protein level reduced. CONCLUSION: These results suggest that RXM inhibits tumor angiogenesis in human hepatoma, and that VEGF alteration may be involved in the mechanism of this inhibitory effect. Because RXM is widely used in clinical practice, it may represent an effective new strategy for human hepatoma therapy.

Enhanced production of vascular endothelial growth factor by human monocytic cells stimulated with endotoxin through transcription factor SP-1.

The effect of endotoxin on the regulation of vascular endothelial growth factor (VEGF) mRNA expression in human monocytic (THP-1) cells was examined. Endotoxic lipopolysaccharide (LPS) from Escherichia coli and synthetic E. coli-type lipid A (LA-15-PP) enhanced VEGF mRNA expression. LPS-induced VEGF mRNA accumulation was regulated, at least in part, at the transcriptional level. Enhancement of VEGF gene expression by LPS was shown by gel shift analysis and use of transcription factor inhibitors to be mediated via the activation of SP-1.

Anandamide induces matrix metalloproteinase-2 production through cannabinoid-1 receptor and transient receptor potential vanilloid-1 in human dental pulp cells in culture.

INTRODUCTION: Anandamide (N-arachidonoylethanolamine [AEA]) is one of the main endocannabinoids. Endocannabinoids are implicated in various physiological and pathologic functions, inducing not only nociception but also regeneration and inflammation. The role of the endocannabinoid system in peripheral organs was recently described. The aim of this study was to investigate the effect of AEA on matrix metalloproteinase (MMP)-2 induction in human dental pulp cells (HPC). METHODS: We examined AEA-induced MMP-2 production and the expression of AEA receptors (cannabinoid [CB] receptor-1, CB2, and transient receptor potential vanilloid-1 [TRPV1]) in HPC by Western blot. MMP-2 concentrations in supernatants were determined by enzyme-linked immunosorbent assay. We then investigated the role of the AEA receptors and mitogen-activated protein kinase in AEA-induced MMP-2 production in HPC. RESULTS: AEA significantly induced MMP-2 production in HPC. HPC expressed all 3 types of AEA receptor (CB1, CB2, and TRPV1). AEA-induced MMP-2 production was blocked by CB1 or TRPV1 antagonists and by small interfering RNA for CB1 or TRPV1. Furthermore, c-Jun N-terminal kinase inhibitor also reduced MMP-2 production. CONCLUSIONS: We demonstrated for the first time that AEA induced MMP-2 production via CB1 and TRPV1 in HPC.