Detection of SMO gene mutations in odontogenic keratocyst / 中华口腔医学杂志

Objective: To detect the SMO mutations in odontogenic keratocyst (OKC) and to explore the mechanism behind. Methods: Patients with OKC who received treatment in the Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology,Peking University, from September 2012 to June 2017 were enrolled. OKC samples from 10 patients diagnosed as naevoid basal cell carcinoma syndrome (NBCCS)-related OKC (4 females and 6 males) and 20 patients diagnosed as sporadic OKC (7 females and 13 males) were collected. Genomic DNAs were extracted from fibrous capsules and epithelial lining respectively. SMO mutations were detected and analyzed by Sanger sequencing. Results: Three SMO mutations were found in one NBCCS-associated OKC who carrying c.2081C>G (p.P694R) mutation) and two sporadic OKC who carrying c.907C>T (p.L303F) mutation and c.1247_1248delinsAA (p.G416E), respectively), among which the first two mutations were novel mutations that had not been reported before. Besides, two mutations in sporadic OKC were not paired with PTCH1 mutations. Conclusions: In addition to PTCH1 gene mutations, SMO gene mutations also exist in OKC which might be related to the development of OKC.

[Comparison of the expression level of P53 and proliferating cell nuclear antigen [PCNA] genes in the inflamed and non-inflamed dentigerous cysts]

The role of P53 and proliferating cell nuclear antigen [PCNA] genes in inflamed and non-inflamed odontogenic cysts is related to cell proliferation but it is unclear. The aim of this study was immunohistochemical evaluation of P53 and PCNA expression in inflamed and non-inflamed dentigerous cysts. In the present study, 23 dentigerous cysts [12 inflamed and 11 non-inflamed] were surveyed. Three microns slices were got from paraffined blocks and stained with P53 and PCNA antibodies by immunohistochemistry. Slides were seen by oral pathologist with optical microscope [Olympus BX41] in x400 magnification and scored by Allred scoring. Data were analyzed by Mann-Whitney test via SPSS software. Percent of stained cells in inflamed compared non-inflamed dentigerous cyst did not show any significant difference for expression level of P53 and PCNA in basal and suprabasal layers [P> 0.05]. It seems that inflammation does not affect on expression level of P53 and PCNA in dentigerous cyst