Odontogenic epithelial proliferation is correlated with COX-2 expression in dentigerous cyst and ameloblastoma.

Investigation of cyclooxygenase (COX)-2 in dentigerous cyst and ameloblastoma may help to improve understanding of the nature and behavior of odontogenic cysts and tumors, and in addition may eventually represent a definitive target for a pharmacological approach in the management of these lesions. The aim of this study was to evaluate COX-2 expression and its correlation with the proliferation of odontogenic epithelium in these lesions. Dentigerous cysts (n=16) and ameloblastomas (n=17) were evaluated. Detection of Ki-67 and COX-2 protein expression was conducted by immunohistochemistry. Data were statistically analyzed using Mann-Whitney U test and Spearman's rank correlation coefficient. No significant differences were found in the expression of Ki-67 and COX-2 between dentigerous cysts and ameloblastomas (P>0.05). A significant positive correlation (P=0.018) and highly significant positive correlation (P=0.004) were found between Ki-67 and COX-2 expression in the odontogenic epithelium of dentigerous cyst and ameloblastoma, respectively. COX-2 was expressed in the odontogenic epithelium of dentigerous cyst and ameloblastoma. It may contribute to local extension of these lesions by increasing the proliferation of their odontogenic epithelial cells.

Expression of human papillomavirus is correlated with Ki-67 and COX-2 expressions in keratocystic odontogenic tumor.

The aim of the current study was to investigate the presence of human papillomavirus (HPV) and evaluate its association with Ki-67 and cyclooxygenase-2 (COX-2) expressions in keratocystic odontogenic tumor (KCOT). Nineteen cases were included in the present study. Conventional PCR method and immunohistochemical analysis were performed for the detection of HPV-DNA and HPV-L1 capsid protein. Moreover, the expressions of Ki-67 and COX-2 proteins were analyzed immunohistochemically. HPV-DNA was detected in 36.8% (7/19) of tumor samples, whilst HPV-L1 protein was identified in 68.4% (13/19) of them. The Kappa coefficient statistical test showed a moderate agreement (κ 0.424) between PCR and IHC assays for HPV detection. Expression of HPV-DNA was positively correlated with Ki-67 and COX-2 expressions (p < 0.05), whereas HPV-L1 positive staining was positively correlated with COX-2 (p < 0.05) and highly associated with those of Ki-67 (p < 0.01). There was no significant correlation between the presence of HPV and the recurrence of the studied lesions. The results of the current study showed that active HPV infection was present in the odontogenic epithelium of KCOT, and it was associated with increased proliferation rate and COX-2 expression. These findings suggest that HPV may have a role in the pathogenesis and aggressiveness of KCOT. Based on these conclusions, we recommend further investigations of HPV vaccine or antiviral therapy and COX-2 inhibitors as nonsurgical options in the prevention and management of KCOT.

[Expressions of RORγT; and FOXP3 and clinical significance in patients with oral lichen planus].

PURPOSE: Oral lichen planus was considered as T cell mediated autoimmune disease affecting oral mucosa with unknown etiopathogenesis. Helper T lymphocytes played an important role in the pathogenesis of OLP. The purpose of this study was to investigate the possible role of Th17 and Treg cells in OLP lesions. METHODS: Forty three patients with OLP (24 patients with reticular OLP and 19 patients with atrophic-erosive OLP) and 13 healthy volunteers were recruited in this study. Real-time quantitative PCR was performed to detect the expressions of RORRORγT and FOXP3, which were the lineage-specific transcription factors for Th17 and Treg, respectively. Statistical difference was evaluated by GraphPad Prism 5 software. RESULTS: The results showed that the expressions of RORRORγT and FOXP3 in OLP lesions were significantly higher than that in normal oral mucosa, and correlated with the clinical classification of OLP. Additionally, it was found that RORRORγT/FOXP3 ratio in atrophic-erosive OLP was significantly higher than that in reticular OLP and control group; Moreover, increased RORRORγT/FOXP3 ratio in reticular OLP was found compared with control group, but the difference was not statistically significant. CONCLUSIONS: The results demonstrate that Th17 and Treg cells participate in the immune response in OLP lesions. Th17 predominance of Th17/Treg imbalance may implicate the immune response in atrophic-erosive OLP. These findings help to broaden our view on the pathogenesis of OLP.

[The level of PPTA mRNA and its proteins expression in trigeminal ganglia in rats with occlusal recovery].

PURPOSE: To study the level of substance P(SP) and preprotachykinin A(PPTA) mRNA in trigeminal ganglia(TG)in rats with occlusal recoveryìand to discuss the mechanism of temporomandibular disorders. METHODS: 48 Wistar male rats were randomly divided into 3 experimental groups and 3 control groupsì8 rats in each group. The right maxillary and mandibular molars in the experimental groups were ground to the gingival level without occlusal contact. The occlusal contact was recovered by stoping grinding the molars gradually. The section of trigeminal ganglia were used for immunohistological and in situ hybridization study. Light microscope and microscoic photo analytic software were employed to detect the percentage of SP and PPTA mRNA positive neurons in the frozen section of TGs in 48 rats. SPSS10.0 software package were used for statistical analysis. RESULTS: The percentage of SP positive neurons in TG with unilateral chew experimental group decreased significantly compared to the control group (P<0.01,P<0.05).The decreased extent in the non-chewing side was much higher than that in the chewing side(P<0.05).The percentage of PPTA mRNA positive neurons was significantly higher in both of the chewing and non-chewing sides of the unilateral chew experimental group than that in the control group (P<0.05,P<0.01)ì and that non-chewing side was significantly higher than that in the chewing side(P<0.01).There was no significant difference in the percentage of SP and PPTA mRNA positive neurons between the early occlusal reconstruction the experimental group and the control group(P>0.05), and there was no significant difference of those between the non-chewing side and the chewing side(P>0.05). The results of later occlusal recovery in the experimental group was same to that of the unilateral chew experimental group. CONCLUSIONS: The expressions of SP and PPTA mRNA in TG can recover normal in the early occlusal recovery but can not in the later occlusal recovery. SP and PPTA mRNA might participate in the histopathologic mechanism of temporomandibular disorders.

[Effects of basic fibroblast growth factor on the proliferation of human salivary adenoid cystic carcinoma cell line ACC-2 and extracellular signal-regulated kinase, Cyclin D1, p2waf/cip1 signaling pathway].

OBJECTIVE: To investigate the effects of basic fibroblast growth factor (bFGF) on the proliferation of human salivary adenoid cystic carcinoma (ACC) cell line ACC-2 in vitro. RESULTS: The effect of ectogenic bFGF on proliferation of ACC-2 was observed by MTT assay. Extracellular signal-regulated kinase (ERK) activity was measured by immuno-precipitation. p-ERK1/2, Cyclin D1 and p21waf/cip1 expression were assessed by Western blot. RESULTS: bFGF could enhance the proliferation of ACC-2. Stimulated by bFGF, the proliferation ratio increased significantly. The intracellular ERK activity, p-ERK1/2 and Cyclin D1 expression were increased, while p21waf/cip1 expression was inhibited by different concentrations of bFGF. The above effects of bFGF could be attenuated by MEK inhibitor U0126. CONCLUSION: bFGF stimulates the proliferation of ACC-2 in a dose dependent manner. The proliferation effect of bFGF may be due to up-regulating ERK, Cyclin D1 and p21waf/cip1 signaling pathway. This research can help us to explore a new pathogenesis and therapy of the ACC.

[Construction of antisense human tankyrase-1 RNA retroviral vector and its inhibition on tongue cancer cells].

OBJECTIVE: To investigate the inhibition of telomerase activity and cellular proliferation in tongue cancer TCCA-8113 cell lines by antisense human tankyrase-1 RNA treatment, and explore the possibility of the tankyrase-1 as a target of gene therapy for tongue cancer. METHODS: The replication deficient retrovirus expressing tankyrase-1 antisense RNA was constructed to infect the TCCA-8113 cells. Tankyrase-1 expression was examined by RT-PCR. Telomerase activity was assayed by telomerase repeat amplification protocol (TRAP). Cell proliferation was investigated by cellular growth curve. Cellular apoptosis was detected by flow cytometry method and invert microscope. RESULTS: Tankyrase-1 expression and telomerase activity of tongue cancer TCCA-8113 cells were significantly inhibited. There was G(1)-S phase arrest when TCCA-8113 cells were treated with antisense tankyrase-1 transduction. Cellular proliferation was arrested, and cellular apoptosis occurred after antisense tankyrase transduction. CONCLUSIONS: The transduction of antisense tankyrase-1 by retroviral vector can significantly inhibit the tankyrase-1 expression and telomerase activity of tongue cancer TCCA-8113 cell lines, and arrest the cellular proliferation and promote cellular apoptosis. The tankyrase may be a potential target of gene therapy for tongue cancer.

[The study of magnetic resonance sialography in diagnosing parotid diseases].

OBJECTIVE: To study the feasibility of diagnosing parotid disease with magnetic resonance sialography (MRS) and to select the optimal scanning sequence. METHODS: Twenty-three patients with parotid gland disease and 5 normal adults received sialography using magnetic resonance imaging technique and several sequences (including IR-FSE, FSE, SS-IR-FSE, SS-FSE) were used. After first scanning, the patients were scanned respectively 3 and 10 minutes after buccal application of vitamin C. And MR images of duct obtained. The images of parotid duct system were analysed and evaluated according to their displaying effects. Qualitative diagnosis was made based on MRI and those diagnosis were compared with pathological diagnosis after operation. RESULTS: Images of MR sialography clearly displayed the main duct and its branches of parotid gland and the pathological changes of duct, such as narrow, expanded, stoppage. Of the scanning sequences, IR-FSE was superior to others in manifesting the parotid gland duct (P < 0.05). The performance of images after being given vitamin C did not significantly improve the displaying effect. The accurate rate of qualitative diagnosis was 95.6%. CONCLUSIONS: MR sialography can clearly display the parotid ducts and their pathological changes. The accurate rate of qualitative diagnosis of parotid disease was higher than that X-ray sialography.