Nuclear to cytoplasmic shift of p33(ING1b) protein from normal oral mucosa to oral squamous cell carcinoma in relation to clinicopathological variables.

PURPOSE: p33(ING1b), as a candidate tumour suppressor gene, has been found to be expressed a proportion of oral squamous cell carcinomas (OSCCs), however, its clinicopathological significance is not studied yet. Our aim was to investigate association of p33(ING1b) expression with clinicopathological variables and particularly interesting new cysteine-histidine rich protein (PINCH) in OSCCs. METHODS: p33(ING1b) expression was immunohistochemically examined in 20 normal oral mucosa specimens and 49 OSCCs. RESULTS: Normal squamous cells showed only p33(ING1b )nuclear expression (no cytoplasmic expression), with a rate of 90% positive cases. While 24% of OSCCs appeared cytoplasmic expression (11 of them with weak nuclear staining) and the rest tumours (76%) were negative for p33(ING1b). Furthermore, the cases having lymph node metastasis showed a higher frequency of positive cytoplasmic expression than those without metastasis (P = 0.03). The p33(ING1b) cytoplasmic expression was positively related to PINCH expression (P = 0.04), the cases positive for both proteins had a high rate of the metastasis (P = 0.03). CONCLUSIONS: The transfer of p33(ING1b) protein from the nucleus to the cytoplasm may result in loss of normal cellular function of the protein, which might play a role in the tumourigenesis and metastasis of OSCCs.

[Effect of periodontitis on circulating C-reactive protein in type 2 diabetes patients].

OBJECTIVE: To investigate the effect of periodontal infection on circulating C-reactive protein (CRP) in type 2 diabetes patients. METHODS: 32 diabetes patients with advanced periodontitis participated in this study. They were compared to a group of 32 diabetes patients without periodontal disease, who were mathed with regard to age (+/- 3 years), gender and body mass index (+/- 1 kg/m2). The concentration of CRP on circulation was measured by ELISA. RESULTS: Significant difference was found in the level of CRP and the percentage of subjects with elevated CRP levels > or = 3 mg/L on circulation between the two groups(P < 0.05). CONCLUSION: Periodontal infection results in higher circulating CRP in type 2 diabetes patients. This elevated inflammatory factor may exacerbate insulin resistance and increase the risk for great vessels complications of diabetes mellitus.

Up-regulation of PINCH in the stroma of oral squamous cell carcinoma predicts nodal metastasis.

Particularly interesting new cysteine-histidine rich protein (PINCH), an adapter protein involved in integrin and growth factor signalling, is up-regulated in the stroma of colorectal, breast, prostate, lung and skin cancer. Strong stromal immunostaining for PINCH is an independent prognostic indicator for reduced survival in colorectal cancer, suggesting that PINCH is involved in the signalling that promotes tumour progression. Since no study on PINCH has been carried out in oral squamous cell carcinoma (OSCC), this study aimed to determine PINCH expression in OSCC and its clinicopathological significance. PINCH protein expression was examined by immunohistochemistry in 20 normal oral mucosa and in 57 OSCC specimens. The frequency of strong PINCH immunostaining was higher in tumour-associated stroma of OSCC (37%) as compared to normal oral mucosa (10%) (p=0.02). Strong PINCH stromal immunostaining predicted nodal metastasis: 19/26 (73%) OSCC cases with nodal metastasis had strong PINCH immunostaining compared to 9/31 (29%) cases without nodal metastasis (p=0.02). The PINCH expression in OSCC was more intense in stroma at the invasive edge than in intratumoural stroma. In conclusion, the up-regulation of PINCH protein in stroma may be involved in promoting invasion and metastasis in OSCC.

[Apoptosis of human oral epidermoid carcinoma KB cells and multidrug resistant KBv200 cells induced by matrine].

OBJECTIVE: To investigate the induction of apoptosis on human oral epidermoid carcinoma KB cells and multidrug resistant KBv200 cells by Matrine. METHODS: MTT assay was used to investigate the inhibition ability of Matrine on the cells in vitro. Transmission electron microscope was used to observe the ultrastructure feature of cells. after treated by Matrine. Acridine orange (AO)/Ethidium bromide (EB) fluorescent staining and flow cytometry were used to observe apoptosis induced by Matrine. Flow cytometry was applied to study the effects of the drug on cell cycles of the cells. RESULTS: When 0.50, 1.00, 1.50, 2.00 mg/ml of Matrine was used, the vital rates of KB and KBv200 cells were decreased according to Matrine's concentration. The IC50 concentrations of Matrine on KB and KBv200 cells were 1.35 mg/ml and 1.43 mg/ml individually. The results of AO/EB fluorescent staining and flow cytometry showed that Matrine could induce apoptosis of two kinds of cells. While observed by transmission electron microscope, there were more contraction of cells, condensation of nuclei, bubble of cytoplasm in both kinds of cells after treated by Matrine. Matrine could stop the growth of KB and KBv200 cells at S period and restrain mitosis of cells. CONCLUSION: Matrine can inhibit the growth of KB and KBv200 cells by inducing apoptosis. The apoptosis effect is dose-dependent and it has certain relation to the blocking of S period cells.