Primary central carcinoma ex pleomorphic adenoma of the mandible: report of a rare case and literature review.

We report a rare case of primary carcinoma ex pleomorphic adenoma (CXPA) of the mandible. A 13-year-old girl presented with a large mass, measuring about 30 cm in its greatest dimension, involving the mandible. She was referred to our department for surgery, and her postoperative course was uneventful; she is currently free from the disease 48 months after surgery. Primary CXPAs located centrally within the jawbones are rare with only 10 cases reported in the English and Chinese literature. This case illustrates 2 key facts regarding the diagnosis and therapy of CXPA. First, clinicians should be aware of this possibility and should emphasize the need for submission of so-called cystic lytic lesions for histopathologic analysis. Second, tumors should be excised en bloc with adjuvant postoperative radiotherapy when local recurrence and regional metastasis are suspected clinically.

Effects of cigarette smoke condensate and nicotine on human gingival fibroblast-mediated collagen degradation.

BACKGROUND: Members of the matrix metalloproteinase (MMP) family have been shown to be involved in periodontal disease. Risk factors for periodontal disease include tobacco smoking. Cigarette smoke condensate (CSC) is comprised of thousands of chemicals. Nicotine is one of the active components in tobacco. This study compares the effects of CSC and nicotine at the level in CSC on the collagen-degrading ability of human gingival fibroblasts (HGFs) and the expression of selected MMPs and tissue inhibitors of metalloproteinases (TIMPs). METHODS: HGFs were seeded in six-well collagen-coated plates, exposed to 100 µg/mL (2.4 µg/mL nicotine) of CSC or 2.4 µg/mL nicotine for 3 days, and then collagen degradation was analyzed. After 3 days exposure to CSC or nicotine, the conditioned media from HGFs was collected and the membrane proteins were extracted for gelatin zymography and Western blot analyses. The mRNA levels of MMP-2, MMP-14, and TIMP-2 were measured by reverse transcription-polymerase chain reaction. RESULTS: The CSC increased collagen degradation, and increased the levels of TIMP-2, MMP-14, and the active MMP-2 in the membrane extracts, and their mRNA levels. CSC also increased the level of active MMP-2 in the conditioned media. Nicotine at the level in CSC (2.4 µg/mL) had little influence on collagen degradation, as well as on the protein and mRNA levels of MMP-2, MMP-14, and TIMP-2. CONCLUSIONS: CSC may increase HGF-mediated collagen degradation by affecting membrane-associated MMPs and TIMPs.

Malignant transformation of oral lichen planus: a retrospective study of 23 cases.

OBJECTIVE: Oral lichen planus (OLP) is a common mucocutaneous disease with malignant transformation potential. The aim of this retrospective study was to investigate the characteristics of patients with OLP who developed oral squamous cell carcinoma (OSCC). METHOD AND MATERIALS: The medical records of 2,119 patients with OLP at West China College of Stomatology, China, from 1951 to 2006, were reviewed. Data were taken from the records of 23 patients with OLP who developed OSCC. RESULTS: The rate of malignant transformation in OLP was 1.1%. The mean age of these patients was 52 years. There were 12 women and 11 men. There was no significant difference between women and men (P = .835). The most common site of malignant transformation was in the tongue (16; 69.57%). The average time from the patient's first visit with OLP to malignant transformation was 16 months (range, 1 to 41 months). More than 50% of patients had alcohol (12; 52.17%) and tobacco (13; 56.52%) habits. Before the malignant transformation, the most frequent symptoms in patients with OLP were pain (21; 91.30%) and erosion (17; 73.91%). CONCLUSIONS: The risk of malignant transformation in OLP is real but not high. Erosive OLP in older patients with pain and who use tobacco and alcohol is more likely to exhibit malignant transformation.

[Clinical evaluation of composite inlays in defective molars].

OBJECTIVE: To evaluate clinical effect of composite inlays in the defective molars. METHODS: A total of 200 defective molars from 163 patients were divided into two groups, including 100 molars of each. One group was restored with the direct composite inlays and another group with the traditional composite fillings. All the restorations were evaluated in oral cavity after 6-month and 5-year filling or insertion with United States public health service criterions. The data were analyzed using SPSS 11.0 software with the chi-square test. The significance level was set at 5%. RESULTS: In clinical service for 6 months, the successful rate of composite inlays was 91.8% (90/98) and the corresponding figure for traditional composite fillings was 91.8% (89/97), but there was no statistically significant difference (P > 0.05). In clinical service for 5 years, the successful rate of composite inlay was 87.9% (80/91), the corresponding figure for the traditional composite fillings being 67.4% (60/89) and the difference was statistically significant (P < 0.05). CONCLUSIONS: In clinical, the defective molars can be well restored with the direct composite inlays. Especially in the long-term clinical service, the composite inlays show significant superiority over the traditional composite fillings.

[Effect of focal adhesion kinase on biological characteristics of Tca8113 tongue squamous cell carcinoma].

OBJECTIVE: To investigate the effect of FAK on biological characteristics of tongue squamous cell carcinoma cell Tca8113. METHODS: Lipofect was used to transfect FAK into Tca8113 cell lines. The difference in expression of FAK between the transfected and non-transfected cell lines was detected by immunofluorescence assay. Then by use of transwell room and wash way, the difference in invasion and adhesion ability between the transfected and non-transfected cell lines was tested. MTT method was adopted in finding the change of proliferation. RESULTS: RT-PCR analysis showed that the FAK gene was downregulated by Tca8113 cells. FAK expression was significantly down regulated by the transfection of FAK ASODN (P<0.05). Antisense FAK ODN significantly inhibited proliferation, adhesion and the invasion of Tca8113 cells. CONCLUSION: FAK plays an important role on biological characteristics of tongue squamous cell carcinoma cell Tca8113.

[Expression and clinical significance of focal adhesion kinase in oral squamous cell carcinoma].

OBJECTIVE: To study the correlation between expression levels of focal adhesion kinase (FAK) in oral squamous cell carcinoma (OSCC) and clinical prognosis with pathologic parameters. METHODS: Eighty paraffin embedded tissue specimens of OSCC were studied by immunohistochemistry. The data was analyzed by SPSS statistical software. RESULTS: FAK was highly expressed in OSCC tissues, in contrast to none or a low expression in normal oral epithelial tissue, and the heterogeneous staining was mainly located in the cell membrane and cytoplasm. FAK overexpression significantly correlated with histological differentiation and TNM stage, lymphatic metastasis. Multivariate analysis revealed that overexpression of FAK was the independent prognostic factor. CONCLUSION: The overexpression of FAK in the peripheral area of OSCC may serve as a useful biological factor affecting prognosis.