[MiR-99a inhibits proliferation of oral squamous cell carcinoma by targeting mTOR pathway].

PURPOSE: To investigate miR-99a expression and its effect on proliferation of oral squamous cell carcinoma (OSCC). METHODS: miRNA microarrays associated with OSCC were identified in GEO database. The expression levels of miR-99a were detected in 63 OSCC tissues and adjacent normal tissues and cell lines. The relationship between clinicopathological parameters and miR-99a expression was analyzed by using ANOVA analysis. The ability of cell growth and clone formation were examined in SCC9 and SCC25 cells transfected with miR-99a mimics. The target genes of miR-99a were predicted by Targetscan software. There resulting data were analyzed using SPSS 19.0 software package. RESULTS: The differently expressed miRNAs were analyzed based on GSE103931 microarray. miR-99a was significantly downregulated in OSCC tissues and cell lines. miR-99a expression was significantly associated with T stage, pathological grading and patients' prognosis. miR-99a overexpression inhibited OSCC cell proliferation and clone formation, while miR-99a inhibition contributed to decreased proliferation and clone formation ability. In addition, miR-99a combined with mTOR gene's 3'UTR was negatively correlated with mTOR expression in OSCC tissues. CONCLUSIONS: miR-99a functions as a tumor suppressor in OSCC and inhibits OSCC cell proliferation by targeting mTOR.

[Clinical study on united crowns or bridges for restoration of posterior teeth with insufficient maxillary bone by means of maxillary tuberosity dental implants].

PERPOSE: To evaluate the clinical effect of united crowns or bridges for restoration of posterior teeth with insufficient maxillary bone by means of tilted dental implants. METHODS: Patients who underwent dental implant surgery in posterior teeth with insufficient maxillary bone were collected and divided into two groups (40 in each group). Patients in the experimental group were treated with titled dental implantation, while patients in the control group were treated with maxillary sinus lifting. Implant retention, marginal bone loss, incidence of adverse reactions, time needed for implantation and cost were recorded and analyzed with SPSS 19.0 software package. RESULTS: After follow up of 2 year, the experimental group had a cumulative survival rate of 100%, marginal bone resorption was (0.31±0.27)mm on average, no sinusitis and massive haemorrhage were noted, The control group had a cumulative survival rate of 96.43%, marginal bone resorption was (0.28±0.26) mm on average, sinusitis and massive haemorrhage occurred in 9.5%,4.8% of patients, the difference was not statistically significant（P＞0.05）. In the experimental group, maxillary sinus mucosa perforation and postoperative pain occurred in 0%,7.5% of patients, duration of operation was （30.55±8.21）min, average cost of each implant was （6.9±0.5）thousand RMB; while in the control group, maxillary sinus mucosa perforation and postoperative pain occurred in 14.3%,28.6% of patients, duration of operation was （50.32±10.80）min, average cost of each implant was (0.98±0.06) thousand RMB, the difference was significant（P＜0.05）. CONCLUSIONS: It is feasible to use united crowns or bridges for restoration of posterior teeth with insufficient maxillary bone by means of maxillary tuberosity dental implants.