Centrosome amplification and chromosome instability in oral squamous cell carcinomas / 中华口腔医学杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSIONS</b>Centrosome abnormality may be a contributing factor for chromosome instability in OSCC.</p>

Cyclin E overexpression and centrosome amplification in squamous cell carcinoma of oral cavity / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the correlation between cyclin E protein overexpression and centrosome amplification in oral squamous cell carcinoma (OSCC).</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>Up-regulation of cyclin E protein may represent one of the possible mechanisms for centrosome amplification in OSCC.</p>

MRI findings of juvenile acute pure cartilage fracture of the knee joint / 中华放射学杂志

Objective To study the MRI manitestation of juvemle acute pure cartilage fracture of the knee joint.Methods The MRI changes of cartilage,subcartilage low signal line and subcartilage bone were analysed retrospectively in 26 juvenile patients with acute pure cartilage fracture confirmed by arthroscopy.Sagittal and coronal MRI scanning were performed in 26 patients.Using fast low angle shot fat saturation T_1-weighted image(FLASH-FS-T_1WI)sequences,spin echo T_1-weighted image(SE-T_1WI)and fast imaging with steady-state precession three dimensional fat saturation T_2-weighted image(FISP-3D-FS- T_2WI)sequences in sagittal plane,SE-T_1WI and multi echo data image combination T_2-weighted imaging (MEDIC or ME-T_2WI)in coronal plane.Using ME-T_2WI sequence,axial plane MRI scanning in 5 patients.Results Twenty-seven sites of 26 patients include 8 patella,7 femoral medial condyle, 11 femoral lateral condyle and 1 tibial plateau.Three types pure cartilage fracture were observed,totally defect of the cartilage in 7 sites(include 3 patella,2 femoral medial condyle,1 femoral lateral condyle and 1 tibial plateau),fissuring fracture in 3 sites(include 2 femoral medial and 1 femoral lateral condyles), superficial defect of the cartilage in 17 sites(include 5 patella,3 femoral medial and 9 femoral lateral condyle).Corpus liberum was found in 21 patients'knee joints by arthroscopy,but only 3 cases by MRI. Bone bruise was detected,and subcartilage low signal lines were normal.Conclusion Using FLASH-FS- T_1WI,SE-T_1WI,FISP-3D-FS-T_2WI and ME-T_2WI sequences,sagittal and coronal MRI scanning in femoral and tibial plateau pure cartilage fractures,and using ME-T_2WI sequence axial scanning in patella r cartilage fractures may show the position,extension and types of the acute pure cartilage fracture of the knee joint. MRI is the hest non-invasive method for studying cartilage fracture.