口腔疣状癌E-cadherin基因蛋白免疫电镜研究

目的 从超微定位水平检测上皮钙粘附素(E-cadherin,E-cd)蛋白在口腔疣状癌中的表达,探讨其在口腔疣状癌发生中的作用。方法 采用免疫电镜技术检测13例口腔疣状癌、10例高分化鳞癌和10例低分化鳞癌E-cd基因蛋白的表达。结果 E-cd在正常口腔粘膜上皮细胞和口腔疣状癌及鳞癌细胞中主要位于胞膜及胞浆上,其中在胞膜主要定位于桥粒,胞浆主要定位于粗面内质网和线粒体上。E-cd在正常口腔粘膜、口腔疣状癌、高分化鳞癌、低分化鳞癌中的阳性表达率分别为87.5％(7/8)、61.5％(8/13)、50.0％(5/10)和30.0％(3/10)。口腔疣状癌E-cd蛋白的平均染色强度与高分化鳞癌间无显著差异,但明显低于正常粘膜组(P<0.05)而高于低分化鳞癌(P<0.05)。结论 E-cd基因蛋白在口腔疣状癌的发生及临床表型中起重要作用。     

口腔疣状癌VEGF基因蛋白免疫电镜研究

目的　从超微定位水平检测血管内皮生长因子 (VascularEndothelialGrowthFactor ,VEGF)蛋白在口腔疣状癌中的表达 ,探讨其在口腔疣状癌发生中的作用。方法　采用免疫电镜技术检测 13例口腔疣状癌、10例高分化鳞癌和 10例低分化鳞癌VEGF基因蛋白的表达。结果　口腔疣状癌VEGF主要定位于肿瘤细胞胞浆和血管内皮细胞核和核膜上 ;在胞浆主要定位于粗面内质网和线粒体上。VEGF在正常口腔黏膜 ,口腔疣状癌 ,高分化鳞癌 ,低分化鳞癌中的阳性表达率为 0 .0 % ( 0 / 8)、3 0 .8% ( 4 / 13 )、5 0 .0 % ( 5 / 10 )和 60 .0 % ( 6/ 10 )。口腔疣状癌VEGF蛋白的平均染色强度低于高、低分化鳞癌 ,差异有显著性 (P <0 .0 5 ) ,但其染色强度明显高于正常黏膜组 (P <0 .0 5 )。高分化鳞癌与低分化鳞癌染色强度间无显著差异 (P >0 .0 5 )。结论　VEGF蛋白在口腔疣状癌的发生及临床表型中起重要作用 ,与口腔鳞状细胞癌的组织学分级无明显关系     

口腔疣状癌中MMP-2的表达及意义

目的 :研究口腔疣状癌中基质金属蛋白酶 (MMP 2 )的表达 ,探讨其不同生物学行为的分子基础。方法 :15例口腔疣状癌标本 ,10例正常口腔黏膜标本 ,2 0例口腔鳞癌 (高、低分化鳞癌各 10例 )标本 ,应用免疫组织化学S P法检测上述标本MMP 2表达和分布。结果 :口腔疣状癌和口腔鳞癌中MMP 2主要表达于癌细胞胞浆 ,正常口腔黏膜MMP 2阴性表达。口腔疣状癌MMP 2阳性表达率为 3 3 .3 % (5 /15 ) ,平均染色强度低于高分化鳞癌和低分化鳞癌组 (P <0 .0 5 )。口腔疣状癌、口腔高分化鳞癌、口腔低分化鳞癌MMP 2表达均高于正常口腔黏膜组(P <0 .0 5 )。结论 :口腔疣状癌细胞产生的MMP 2 ,导致基底膜成分Ⅳ型胶原降解 ,破坏基底膜的完整性 ,这可能是口腔疣状癌局部侵袭转移的机制之一。MMP 2在口腔疣状癌、口腔高分化鳞癌、口腔低分化鳞癌的表达存在明显差异 ,证实口腔疣状癌是一种独立类型的恶性肿瘤。     

体外培养鼠口腔黏膜干细胞的超微结构改变

目的：观察体外培养鼠151腔黏膜干细胞超微结构的变化。方法：双重酶消化法分离、培养昆明小鼠口腔黏膜上皮干细胞，光镜下观察干细胞生长及分化特征，透射电镜鉴定细胞的超微结构。结果：鼠口腔黏膜干细胞初始保持未分化的克隆样生长，14d后分化成3种类型细胞，分别代表细胞不同的分化状态。光镜下细胞主要分为两种：一种细胞小而折光性强，另一种细胞大而折光性弱。电镜下，单个细胞的胞质中和满张力原纤维，细胞间形成桥粒结构，符合上皮细胞超微结构特征，可见3种细胞形态：一种细胞胞核大胞质少，一种细胞胞核小胞质多，另有少量细胞的核浓染、固缩。结论：光镜下观察到的小而折光性强的细胞和电镜下观察到的胞核大胞质少的细胞为口腔黏膜干细胞，通过对细胞超微结构的分析将有助于口腔黏膜干细胞的鉴定。     

大鼠切牙造牙本质细胞的超微结构观察

应用透射电镜观察了大鼠切牙造牙本质细胞的超微结构．该细胞呈长柱状，核位于基底部，核仁１～３个，内含大量常染色质．从牙髓侧至牙本质侧，胞浆可分为核下区、核上区与顶浆区。核下区合少量线粒体、内质网和核糖体等，核上区有发达的高尔基器、大量粗面内质网和线粒体等；顶浆区多为微丝、微管和小泡等。造牙本质细胞突起伸入前期牙本质小管内，突起内无主要细胞器，仅有微丝、微管和小泡等。相邻造牙本质细胞间存在间隙，其牙本质侧有连接复合体相连，其它区域则为桥粒。     

P16蛋白在口腔疣状癌组织中的表达及意义

目的 :研究P16蛋白在口腔疣状癌中的表达状况并与其在口腔黏膜鳞状细胞癌的表达对比 ,探讨其在口腔疣状癌发生发展中的生物学意义。方法 :采用SP免疫组化方法分别检测 8例正常口腔黏膜、13例疣状癌、10例高分化鳞癌、10例低分化鳞癌组织中P16蛋白的表达。结果 :疣状癌P16蛋白表达缺失率为 2 3 .1% ( 3 /13 ) ,过度表达率为 69.2 % ( 9/13 ) ,其平均染色强度高于高分化鳞癌和低分化鳞癌组 (P <0 .0 5 )。结论 :P16基因变异在口腔疣状癌的发生过程中起一定作用 ,疣状癌中P16蛋白过度表达提示疣状癌可能与HPV关系密切。     

基质金属蛋白酶抑制剂-1在口腔疣状癌中的表达研究

目的观察基质金属蛋白酶抑制剂(tissue inhibitor of metalloproteinase,TIMP)-1在口腔疣状癌(OVC)中的表达。方法选择15例口腔疣状癌、10例正常口腔黏膜、20例口腔鳞癌标本(高、低分化鳞癌各10例),应用免疫组化S-P法检测TIMP-1的表达和分布。结果口腔疣状癌组织中TIMP-1阳性表达率为80%(12/15),高于高分化鳞癌(60%,6/10)和低分化鳞癌(40%,4/10)(P<0.05);平均染色强度高于高、低分化鳞癌(P<0.05);口腔疣状癌、口腔高分化鳞癌、口腔低分化鳞癌组织中TIMP-1的表达均高于正常口腔黏膜组织(P<0.05)。结论OVC是一种不同于口腔鳞状细胞癌的独立类型的恶性肿瘤,TIMP-1可以抑制肿瘤的浸润与转移。     

人牙周膜成纤维细胞在纯钛表面附着的电镜观察

目的：研究人牙周膜成纤维细胞(PDLF)在纯钛金属表面的结合形式和超微结构。方法：将纯钛试件放在12孔培养板内，取生长良好的第五代人牙周膜成纤维细胞接种在试件表面，培养72h后取出，原位包埋法制作透射电镜标本，透射电镜观察。结果：人牙周膜成纤维细胞在纯钛表面附着形式不同于上皮细胞在金属表面的附着形式，细胞与金属结合界面中未观察到典型半桥粒结构。人牙周膜成纤维细胞胞浆中，细胞器发达，富含与蛋白质合成、代谢及增殖等生物学功能有关的细胞超微结构，如粗面内质网、线粒体、核糖体、细胞核等。结论：人牙周膜成纤维细胞在钛金属表面的附着形式，不同于上皮细胞的附着形式，表现为蛋白合成旺盛，可能为细胞直接附着，其具体附着形式还待进一步研究。     

人乳头状瘤病毒16/18型在口腔疣状癌中的表达及意义

目的　研究人乳头状瘤病毒 16 /18型在口腔疣状癌中的表达状况 ,探讨其在口腔疣状癌发生发展中的生物学意义。方法　采用SP免疫组化和原位杂交方法分别检测 8例正常口腔粘膜、13例疣状癌、10例高分化鳞状细胞癌、10例低分化鳞癌组织中HPV16 /18E6蛋白和HPV16 /18DNA的表达。结果　①疣状癌HPV16 /18E6蛋白及HPV16 /18DNA阳性表达率均为 6 9.2 % (9/13) ,E6蛋白平均染色强度高于高分化鳞状细胞癌和低分化鳞状细胞癌组 (P <0 .0 5 )。②免疫组化方法检测HPV16 /18E6蛋白与原位杂交方法检测HPV16 /18DNA结果有良好的一致性。结论　HPV16 /18型感染是口腔疣状癌的重要致病因子 ,与高分化鳞状细胞癌、低分化鳞状细胞癌组织相比 ,HPV16 /18型感染与疣状癌的关系更为密切。     

p53蛋白在口腔疣状癌组织中的表达及意义

目的 :研究口腔疣状癌中p5 3蛋白的表达状况及与口腔粘膜鳞状细胞癌的表达对比 ,探讨p5 3蛋白在口腔疣状癌发生过程中的生物学意义。方法 :采用SP免疫组化方法分别检测 8例正常口腔粘膜、1 3例疣状癌、1 0例高分化鳞癌、1 0例低分化鳞癌组织中p5 3蛋白的表达。结果 :疣状癌p5 3蛋白阳性表达率为 6 9.2 % (9/ 1 3) ,高分化鳞癌组和低分化鳞癌组阳性表达率均为 80 % (8/ 1 0 ) ,而正常口腔粘膜上皮均呈阴性表达 ,疣状癌p5 3蛋白平均染色强度低于高分化鳞癌和低分化鳞癌组 ,差异有显著性 (P <0 .0 5 ) ;高分化鳞癌的平均染色强度低于低分化鳞癌组 ,差异有显著性 (P <0 .0 5 )。结论 :口腔疣状癌的发生过程中可能存在p5 3基因突变 ,疣状癌与高分化鳞癌、低分化鳞癌组织中p5 3蛋白的表达差异可作为其鉴别诊断的有用指标之一     

层粘连蛋白在口腔疣状癌中表达的研究

目的:研究层粘连蛋白(Laminin,LN)在口腔疣状癌中的表达,探讨其在口腔疣状癌发生发展中的作用。方法:取15例口腔疣状癌、10例正常口腔黏膜、20例口腔鳞癌(高、低分化鳞癌各10例),应用免疫组织化学SP法检测上述标本中LN的表达和分布。结果:口腔疣状癌组织中层粘连蛋白阳性表达率为40%,明显高于高分化鳞癌(20%)和低分化鳞癌(0%);口腔疣状癌、高分化鳞癌、低分化鳞癌组织中层粘连蛋白的表达均低于正常口腔黏膜组织(100%)。结论:层粘连蛋白可能在口腔疣状癌的浸润与转移过程中起重要作用。     

Cyclin B1 overexpression in conventional oral squamous cell carcinoma and verrucous carcinoma-A correlation with clinicopathological features

Background: Nuclear localization of cyclin B1 is an indicator for cells undergoing mitotic division, and the overexpression has shown promising results as a good prognostic predictor for patients of squamous cell carcinoma (SCC). Cyclin B1 overexpression among histological grades of conventional oral squamous cell carcinoma (COSCC), as well as comparison with verrucous carcinoma (VC) has been less investigated. Study Design: Immunohistochemical expression of cyclin B1 was compared with various clinicopathological features in 30 primary COSCC and 31 primary VC cases. Result: Cyclin B1 showed significant overexpression for some clinical features for both the variants of oral squamous cell carcinoma. In histopathological variants, statistical significance was observed among grades of COSCC, as well as COSCC and its grades with VC. The concomitant increase in cyclin B1 overexpression from VC to grades COSCC was observed. Conclusion: Our study findings draw attention to cyclin B1 overexpression is involved in early carcinogenesis, cell differentiation and tumor proliferation. Key words:Cyclin B1, oral squamous cell carcinoma, verrucous carcinoma, head and neck cancer.     

基质金属蛋白酶-9及基质金属蛋白酶抑制剂-1在口腔鳞状细胞癌中的表达研究

目的 研究基质金属蛋白酶-9(matrix metalloproteinase-9,MMP-9)及基质金属蛋白酶抑制剂-1(tissue inhibitor of metalloproteinase-1,TIMP-1)在口腔鳞状细胞癌中的表达及其相关性,探讨其在口腔鳞状细胞癌发生发展中的作用。方法 取20例正常口腔黏膜、40例口腔鳞癌(高、低分化鳞癌各20例),应用免疫组织化学SP法检测上述标本中MMP-9及TIMP-1的表达和分布。结果 口腔高分化鳞癌、低分化鳞癌组织中MMP-9、TIMP-1的表达均高于正常口腔黏膜组织(P<0·05)。口腔高分化鳞癌、低分化鳞癌、正常口腔黏膜组织中,MMP-9表达强度依次递增,TIMP-1表达强度依次递减。结论 MMP-9可能在口腔鳞状细胞癌的发生发展中起重要作用,其活性受TIMP-1的负性调控。     

Ultrastructure of oral squamous-cell carcinoma.

Fresh surgical specimens of sixteen cases of oral squamous-cell carcinoma were processed for electron microscopic study. All cases were histologically graded as moderately differentiated carcinoma. As compared to normal oral stratified squamous epithelium, some unusual ultrastructural features were present in carcinoma. These features were spherical or ovoid nuclear bodies composed of concentrically arranged filaments and granules, clustered ribosomes, many lysosomal bodies, cell residues in other cells, absence and multilayering of basal lamina, pseudopodal cytoplasmic projections, microfilaments in peripheral cytoplasm, clusters of swirled tonofilaments, intracytoplasmic desmosomes, and a small amount of glycogen. These features are interpreted as being related to hyperactivity, phagocytosis, locomotion, and differentiation of cancer cells.     

Shifts in cellular localization of moesin in normal oral epithelium, oral epithelial dysplasia, verrucous carcinoma and oral squamous cell carcinoma

BACKGROUND: Moesin, a member of ERM (ezrin/radixin/moesin) family, links actin filaments of cell surface structure to the cell membrane. The purpose of the study is to assess the shifts in cellular distribution of moesin in normal oral epithelium, oral epithelial dysplasia (OED), verrucous carcinoma (VC), and oral squamous cell carcinoma (OSCC). METHODS: The expression of moesin was evaluated immunohistochemically in paraffin-embedded tissues of 59 specimens of OSCC, 35 specimens of OED, 17 specimens of VC, and five specimens of normal oral epithelium. RESULTS: In the normal oral epithelia, all specimens showed a pattern of membranous expression against the anti-moesin antibody in the basal layer cells. In the OED specimens, moesin was dominantly expressed in the cell membrane except for the cornified layer. In VC and OSCC specimens, almost the whole of the carcinoma cells were stained with anti-moesin antibody. However, in OSCC samples, moesin was markedly expressed increasingly in the cytoplasm and decreasingly in the cell membrane, as compared with OED and VC. In addition, there was a significant correlation between the pattern of moesin expression and tumor differentiation in OSCC. CONCLUSIONS: Our results suggest that it is useful to detect the moesin expression as adjunct to screening mucosal lesions in the oral cavity.     

Role of vitamins C and E as chemopreventive agents in the hamster cheek pouch treated with the oral carcinogen-DMBA

OBJECTIVE: To evaluate the role of vitamins C and E as chemopreventive agents in oral carcinogenesis by optical and ultrastructural studies. MATERIALS AND METHODS: The cheek pouch of male hamsters was treated with the oral carcinogen, dimethylbenz(a)anthracene (DMBA), to induce multiple tumour formation. Vitamins C and E were applied either singly or in combination as a chemopreventive agent. Paraffin and resin-embedded sections of the hamster cheek pouch were studied optically and ultrastructurally. RESULTS: The epithelium of control hamsters showed hyperorthokeratosis and parakeratosis, but did not develop well differentiated squamous cell carcinoma (WDSCC). Ninety percent of the animals treated with DMBA alone showed WDSCC while 10% of the animals developed papillomas. There was also a marked increase in the number of cells undergoing mitosis in this group. A reduction in the yield (1.1 tumour/animal) and rate 60-80% of squamous cell carcinomas but not of papillomas (2.0 papillomas/animal) was observed in groups VI-VIII treated with DMBA and vitamins C and E singly or in combination as compared to those of DMBA only. In animals treated with DMBA plus vitamins C and E, statistical significant decrease in the number of animals with tumours and mitotic basal cells was observed when compared with the DMBA treated group. Control animals showed normal ultrastructural morphology while tumour-bearing animals showed basal lamina in a discontinuous, fragmented, broken and diffused basement membrane, with diminished lamina densa, fewer hemidesmosomes and invagination of the basal cell cytoplasmic processes in the subepithelium. CONCLUSION: These results indicate that vitamin E singly or in combination with vitamin C plays a role in the inhibition of tumour cell growth.