[Show abstract][Hide abstract] ABSTRACT: To investigate the relationship between centrosome abnormalities and aneuploidy in oral squamous cell carcinoma (OSCC) and elucidate the possible underlying mechanisms of chromosome instability (CIN) in OSCC.
Formalin-fixed, paraffin-embedded tissues of 8 cases of normal oral epithelium and 32 cases of OSCC were examined for centrosome status by using indirect immunofluorescence staining, and chromosome instability (aneuploidy) in some tissues were detected by flow cytometry. The correlation between centrosome abnormalities and aneuploidy in OSCC was statistically analyzed by SPSS12.0.
Normal oral epithelium showed normal size and number of centrosomes in epithelium cells, while 25 out of 32 cases of OSCC showed the evident centrosome amplification characterized by huge size and/or supernumerary centrosomes in a fraction of tumor cells, and 21 out of 32 cases were aneuploidy. The percentage of cases with abnormal centrosomes in aneuploid OSCC (19/21) was significantly higher than that in diploid OSCC(6/11) (P =0.032). Centrosome abnormality was significantly correlated with aneuploidy (Spearman r = 0.413, P = 0.047), and a positive correlation was found between the degree of centrosome amplification and the degree of DNA ploidy abnormality (Pearson r = 0.364, P = 0.041).
Centrosome abnormality may be a contributing factor for chromosome instability in OSCC.
No preview · Article · Mar 2008 · Zhonghua kou qiang yi xue za zhi = Zhonghua kouqiang yixue zazhi = Chinese journal of stomatology
[Show abstract][Hide abstract] ABSTRACT: To study the correlation between cyclin E protein overexpression and centrosome amplification in oral squamous cell carcinoma (OSCC).
Formalin-fixed, paraffin-embedded tissues from 12 normal oral epithelium cases and 46 cases of OSCC were studied. Their centrosome status was analyzed by indirect immunofluorescence double staining with antibodies to centrosome protein gamma-tubulin and cytokeratin. The expression of cyclin E protein was studied by immunohistochemical methods. The correlation between cyclin E protein expression and centrosome amplification in OSCC was statistically analyzed by SPSS 12.0.
Thirty-seven of the 46 OSCC cases (80.4%) studied showed evidence of centrosome amplification, as signified by enlargement and/or increase in number of centrosomes, while normal oral epithelium possessed centromeres of normal size and number. Positive staining for cyclin E protein was observed in 30 of the 46 OSCC cases (65.2%), while all the normal oral epithelium cases were cyclin E protein-negative. The percentage of centrosome amplification in OSCC with positive cyclin E protein staining (90.0%, 27/30) was higher than that in OSCC with negative cyclin E protein staining (62.5%, 10/16) (chi(2) = 5.014, P < 0.05). Centrosome amplification showed positive correlation with cyclin E protein overexpression (r = 0.330, P < 0.05).
Up-regulation of cyclin E protein may represent one of the possible mechanisms for centrosome amplification in OSCC.
No preview · Article · Jun 2007 · Zhonghua bing li xue za zhi Chinese journal of pathology