金黄地鼠颊囊癌变过程中DPC4的表达特征

目的:研究dpc4基因在金黄地鼠颊囊癌变过程中的表达特征,探讨其与口腔鳞癌的发生、发展之间的关系及临床意义。方法:用免疫组化技术检测23例金黄地鼠颊囊正常上皮、21例单纯增生上皮、27例异常增生上皮、25例鳞癌组织中DPC-4的表达。结果:DPC-4在正常黏膜上皮组织的细胞质内呈稳定性、强阳性表达,在细胞质内出现棕褐色颗粒;在单纯增生上皮中表达与正常黏膜组织相似;在上皮异常增生组织表达降低,阳性率为74.1%;在鳞癌中的表达亦明显降低,阳性率为48%,且与正常黏膜、异常增生黏膜相比有显著性差异(P<0.01)。结论:Smad4的缺失促进了口腔黏膜鳞癌发生发展。     

CDK2在金黄地鼠颊囊癌变过程中的表达的研究

目的探讨CDK2在金黄地鼠颊囊黏膜从正常黏膜到单纯增生、异常增生及鳞癌的表达变化.方法采用DMBA诱导48只金黄地鼠颊囊癌变动物模型,SABC免疫组化法检测CDK2蛋白的表达.结果CDK2在异常增生上皮及鳞癌的表达与正常和单纯增生组相比明显提高(P<0.05),阳性染色等级随病理等级改变提高(P<0.05).结论CDK2参与了口腔黏膜癌前病变和鳞癌的发生与发展.     

金黄地鼠颊囊癌变过程中α-连接素表达的实验研究

目的探讨α-连接素(α-catenin,α-cat)在金黄地鼠颊囊癌变过程中的表达情况及其临床意义。方法采用免疫组织化学的方法检测23例正常金黄地鼠颊囊黏膜上皮组织、22例单纯增生上皮组织、22例异常增生上皮组织、29例鳞癌组织中α-cat的表达情况。结果α-cat在正常金黄地鼠颊囊黏膜上皮组织中均匀、强烈表达;在异常增生组织中α-cat的表达降低,在鳞癌中的表达明显降低,与异常增生相比差异有显著性。结论α-cat的表达减弱与金黄地鼠颊囊癌变密切相关,可作为恶变的一个较好指标。     

金黄地鼠颊囊癌变过程中c-fos和HSP70的表达

目的 :探讨c-fos、HSP70在金黄地鼠颊囊黏膜从正常黏膜到单纯增生、异常增生及鳞癌的表达的变化。方法 :采用DMBA诱导金黄地鼠颊囊癌变动物模型 ,SABC免疫组化法检测c -fos、HSP70蛋白的表达。结果 :c -fos在异常增生上皮及鳞癌的表达与正常和单纯增生组相比明显提高 (P <0 .0 1) ,阳性染色等级随病理等级改变提高 (P <0 .0 1) ;HSP70在鳞癌的表达与正常黏膜相比明显提高 (P <0 .0 5 ) ;c -fos、HSP70的表达有相关性 (P <0 .0 1)。结论 :c -fos高表达是鳞癌发生的早期事件 ,与HSP70在鳞癌的发生发展中协同作用     

核转录因子-κB在金地鼠颊囊癌变过程中的表达研究

目的　探讨核转录因子-κB家族成员的重要亚基p65及其抑制蛋白IκBα在金地鼠颊囊鳞癌发生过程中的 表达及意义。方法　建立金地鼠颊囊癌变的动物模型,采用Western blot法检测金地鼠正常颊黏膜、上皮单纯增生 黏膜、上皮异常增生黏膜和鳞癌组织所提取的核蛋白中p65的表达差异;采用SABC免疫组织化学法检测在金地鼠 颊黏膜正常上皮、上皮单纯增生、上皮异常增生、鳞状细胞癌中IκBα的表达变化。结果　正常黏膜和上皮单纯增生 黏膜中,p65表达很弱,但普遍存在IκBα的表达,该表达多局限于黏膜基底层和棘层底部细胞的胞浆中。随着上皮 异常增生的出现,p65表达增强,与正常黏膜和单纯增生黏膜相比有统计学意义(P<0.01),而IκBα表达则显著下 降(P<0.05)。鳞癌组织中p65的表达显著高于正常黏膜和异常增生黏膜(P<0.01),IκBα的表达显著升高,明显 高于上皮异常增生黏膜(P<0.01),甚至超过正常水平(P<0.01)。结论　p65在金地鼠颊囊鳞癌发生、发展过程中 被激活。p65和IκBα在金地鼠颊囊癌变过程中的表达异常,上皮异常增生阶段p65的表达上调而IκBα的表达下调, 可能是口腔黏膜上皮癌变过程中的早期事件,可作为口腔早期癌变监测的生物学指标。     

金地鼠颊囊癌变过程中IκBα蛋白表达的研究

目的 :探讨核转录因子的抑制蛋白IκBα在金地鼠颊囊鳞癌发生过程中的表达及意义。方法 :建立金地鼠颊囊癌变的动物模型。采用SABC免疫组织化学方法 ,检测在地鼠颊囊黏膜正常上皮 (n =2 2 ) ,上皮单纯增生 (n =2 0 ) ,上皮异常增生 (n =35 ) ,鳞状细胞癌 (n =2 3)中IκBα的表达变化。结果 :各阶段均有IκBα的表达 ,但表达强度不同 ,呈现一种动态变化过程。在正常颊囊黏膜组织和上皮单纯增生组织中IκBα局限表达于基底层和棘层底部细胞的胞浆中。随着上皮异常增生的出现及异常增生程度的加重 ,IκBα表达显著下降 ,较正常组和单纯增生组有显著性差异 (P <0 .0 5 )。一旦鳞癌生成后 ,IκBα表达上调 ,明显高于上皮异常增生组 (P <0 .0 1) ,甚至超过癌变前正常水平 (P <0 .0 1)。结论 :IκBα在金地鼠颊囊癌变过程中的表达异常 ,尤其是在上皮异常增生阶段的表达水平下调 ,可能是口腔黏膜上皮癌变过程中的一个早期事件 ,且可将其作为口腔癌变监测的生物学指标之一     

金黄地鼠颊囊黏膜癌变过程中iNOS的表达与Bcl-2的关系

目的：观察金黄地鼠颊囊黏膜癌变过程中诱导性一氧化氮（inducible nitric oxide synthase，iNOS）的表达与凋亡相关蛋白Bcl-2的关系。方法：6—8周龄金黄地鼠72只，随机分为实验组（60只）和空白对照组（12只），空白对照组地鼠不做任何处理．实验组地鼠用0．5％的二甲基苯丙蒽（dimethyl-benzanthrance，DMBA）丙酮溶液诱导生成颊囊黏膜癌．并在黏膜癌变的不同阶段检测组织中iNOS和Bcl-2的表达。结果：正常地鼠颊囊黏膜组织中未见iNOS阳性表达．组织中iNOS、Bcl-2的表达强度在颊囊黏膜癌变过程中均呈上升趋势。鳞癌组织中iNOS的表达较单纯增生组织显著增强（P〈0．011；鳞癌组织中Bcl-2的表达强度明显高于轻度上皮异常增生组（P〈0．05），但与重度和中度上皮异常增生组之间无显著性差异（P〉0．05）；Bcl-2的表达强度随iNOS表达强度的增强呈现先升后降的复杂变化。结论：一氧化氮参与了颊囊黏膜鳞癌的发生、发展，并可能通过Bcl-2途径调节肿瘤细胞的凋亡。     

灵芝三萜抑制口腔黏膜癌发展过程的实验研究

目的:探讨灵芝三萜在口腔癌变发生发展过程中的抑制作用和机制。方法:建立金黄地鼠颊囊动态癌变的动物模型60只,分2组:A组(灵芝三萜组),B组(对照组),每组30只。采用免疫组化技术检测VEGF在2组动物模型中的表达变化,并进行统计学处理。结果:6周时A组正常黏膜上皮例数多于B组,上皮异常增生率A组明显低于B组(P<0.01),9周时中、重度上皮异常增生和癌变率A组低于B组(P<0.05),12周时A组癌变率低于B组(P<0.01)。在整个癌变动态观察期内,2组颊囊癌变过程中不同组织学发生情况有显著差异(P<0.01),A组病变严重程度始终低于B组。VEGF表达强度随着正常黏膜至鳞癌的发展逐渐增强。在上皮单纯增生、上皮异常增生、鳞癌中A组与B组相比,差异均有显著性(P<0.05)。结论:灵芝三萜对口腔黏膜癌发展过程中具有抑制作用并显示出明显的血管抑制作用。     

口腔黏膜癌前病变和口腔鳞癌组织Fas/FasL的表达及其意义

目的：研究调亡相关基因Fas／FasL在正常口腔黏膜、上皮异常增生和口腔鳞癌组织中的表达及意义。方法：应用免疫组织化学方法检测10例正常口腔黏膜、26例上皮异常增生、38例口腔鳞癌组织及肿瘤浸润淋巴细胞（TIL）中Fas／FasL的表达。结果：Fas在正常口腔黏膜中广泛表达;上皮异常增生和鳞癌组织表达明显下调（P〈0．05）;Fas表达与口腔鳞癌分化程度有关;FasL在正常口腔黏膜不表达;上皮异常增生和鳞癌组织表达明显上调（P〈0．05）;FasL表达与口腔鳞癌分化程度无关（P〉0．05）;TIL细胞Fas、FasL阳性表达率为81．6％和84．2％。结论：Fas表达与口腔黏膜上皮细胞的自然分化成熟、衰老及口腔鳞癌的形成和肿瘤的恶性度有关;FasL的表达上调可能是口腔鳞癌组织免疫反攻击的体现;Fas、FasL可作为监测口腔上皮癌变的标记物。     

CDK2、CDK4在金黄地鼠颊囊癌变过程中表达的研究

目的 探讨CDK2、CDK4在金黄地鼠颊囊黏膜从正常黏膜到单纯增生、异常增生及鳞状细胞癌的表达变化及相关性。方法采用DMBA诱导48只金黄地鼠颊囊癌变动物模型，SABC免疫组化法检测CDK2、CDK4蛋白的表达。结果CDK2、CDK4均在异常增生上皮及鳞状细胞癌的表达与正常和单纯增生组相比明显提高（P〈0．05），阳性染色等级随病理等级改变提高（P〈0．05）。CDK2与CDK4呈高度正相关。结论CDK2、CDK4参与了口腔黏膜癌前病变和鳞状细胞癌的发生与发展。     

E-钙黏素mRNA在大鼠舌黏膜癌变过程中的表达研究

目的:研究上皮型黏附分子E-钙粘素mRNA在大鼠舌黏膜癌变过程中的表达及其意义。方法:采用4NQO饮水法诱导大鼠舌鳞状细胞癌发生,实时荧光定量PCR技术检测组织标本中E-钙粘素mRNA的表达情况。结果:在大鼠舌鳞状细胞癌发生过程中E-钙粘素mRNA表达降低;上皮单纯增生组、轻度上皮异常增生组、中度和重度上皮异常增生组、鳞状细胞癌组4组标本中E-钙粘素 mRNA的表达量分别是上皮正常组标本中的0.453541倍、0.207062倍、0.190954倍、0.180987倍,且鳞状细胞癌组与上皮正常组间的差异具有统计学意义。结论:在大鼠舌黏膜癌变过程中E-钙粘素mRNA表达随着病理分级的增加呈逐渐降低的趋势。E-钙粘素mRNA表达变化是大鼠舌黏膜癌变过程中的早期事件。     

实时荧光定量RT-PCR检测舌癌E-cadherin mRNA的表达

目的:了解E-cadherin在舌癌中的表达及其临床意义.方法:采用实时定量PCR检测29例舌鳞癌患者的癌组织和正常组织中E-cadherin mRNA,分析E-cadherin基因表达与临床病理参数的相关性.结果:舌癌组织中E-cadherin mRNA表达水平2.23±1.16(E-cadherin/β-actin),低于正常组织组8.59±2.71,两组间差异有统计学意义(P＜0.01),E-cadherin mRNA水平与临床病理参数之间无相关性(P＞0.05).结论:E-cadherin的表达下降是舌癌发生过程中的重要事件,实时定量PCR检测E-cadherinmRNA的表达对舌癌早期诊断有重要参考价值.     

Immunohistochemical study of syndecan-1 down-regulation and the expression of p53 protein or Ki-67 antigen in oral leukoplakia with or without epithelial dysplasia

BACKGROUND: Leukoplakia is an oral pre-cancerous lesion that sometimes develops into squamous cell carcinoma. Therefore, leukoplakia with epithelial dysplasia is useful for studying carcinogenesis at the cellular level. The purpose of this study was to evaluate a potential association between the loss of syndecan-1 expression and the expression of p53 protein and Ki-67 antigen, and to identify reliable markers for predicting malignant changes in oral leukoplakia with epithelial dysplasia. METHODS: Changes in the expression of syndecan-1, p53, and Ki-67 were examined immunohistochemically in 43 cases of oral leukoplakia with or without epithelial dysplasia. The subjects were categorized as: none, 13 cases; mild dysplasia, 5 cases; moderate dysplasia, 17 cases; and severe dysplasia, 8 cases. The expression of these molecules in normal oral epithelia (22 cases) was also investigated. RESULTS: Strong syndecan-1 expression was observed on the surface of keratinocytes in normal epithelium. Immunopositivity was lost gradually as the extent of epithelial dysplasia increased. In normal epithelium, p53 and Ki-67 appeared mainly in the basal cell layer, while they were more widely distributed in leukoplakia. Specifically, significant changes were observed in the labeling index of p53 and Ki-67 in leukoplakia as epithelial dysplasia progressed from mild to moderate or severe. CONCLUSION: Our results reveal that overexpression of p53 protein and Ki-67 antigen, and down-regulation of syndecan-1 expression in the lower part of the epithelium, are associated with dysplastic changes. Therefore, the down-regulation of syndecan-1 expression may be the most important reliable marker for dysplastic changes.     

Immunohistochemical evaluation of Fhit protein expression in oral squamous cell carcinomas

The expression of Fhit (fragile histidine triad) protein in oral squamous cell carcinoma (OSCC) and adjacent oral epithelium was evaluated by immunohistochemistry on formalin-fixed paraffin-embedded blocks of 32 cases of OSCC. Rabbit polyclonal anti-GST-Fhit antiserum at 1:600 was used, after antigen enhancement in a microwave pressure cooker, in a saturated lead thiocyanate solution. This antiserum has been shown specifically to detect human Fhit by immunohistochemistry at dilutions up to 1:10,000. The Fhit protein expression was evaluated using both the intensity and extent of staining. Normal stratified squamous epithelium showed strong positivity, especially in the stratum spinosum and areas of keratinisation. Basal and parabasal cells were negative or expressed low levels of Fhit relative to the squamous epithelium. Mild and moderate epithelial dysplasia showed Fhit expression in the superficial layers, while Fhit expression was absent from severely dysplastic lesions. A reduction or loss of Fhit expression was found in 21 (66%) of the OSCC. The alterations in Fhit protein expression in OSCC, and not in normal tissues, are consistent with the proposal that Fhit inactivation plays a role in oral carcinogenesis.     

Changing expression of E- and P-cadherin during rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide

BACKGROUND: Oral squamous cell carcinoma (SCC) develops from pre-malignant lesions, but the role of cell adhesion molecules such as E-cadherin (E-CD) and P-cadherin (P-CD) in the pre-malignant stage has not been elucidated. METHODS: The expression of E-CD and P-CD was examined immunohistochemically and biochemically in a 4-nitroquinoline 1-oxide (4NQO)-induced rat model of carcinogenesis. RESULTS: The expression of E-CD in the pre-malignant stage was the same as that in the normal epithelium. The expression of P-CD was even throughout the prickle cell layer in the dysplasia stage. E-CD and P-CD were expressed in essentially the same locations in SCC and in the pre-malignant stage. P-CD expression was very strong in the pre-malignant stage, compared to that in normal epithelium. CONCLUSIONS: Aberrant P-CD expression in E-CD-positive cells may play a crucial role in the progression of the pre-malignant stage of 4NQO-induced carcinogenesis, and may activate mechanisms responsible for cell proliferation.     

Immunohistochemical localization of growth factors fibroblast growth factor-1 and fibroblast growth factor-2 and receptors fibroblast growth factor receptor-2 and fibroblast growth factor receptor-3 in normal oral epithelium,epithelial dysplasias,and squamous cell carcinoma

OBJECTIVES: Fibroblast growth factors (FGFs) and their receptors (FGFRs) have been identified in a variety of carcinomas, but there are few studies concerning their presence in oral cancers. The objective of this study was to determine whether FGF-1, FGF-2, and high affinity receptors FGFR2 and FGFR3 are present in the pathogenesis of oral epithelial dysplasias and oral squamous cell carcinoma. STUDY DESIGN: Sections from formalin-fixed, paraffin-embedded samples of oral normal mucosa (n = 14), epithelial dysplasia (n = 20), carcinoma in situ (n = 10), and squamous cell carcinoma (n = 12) were tested for cytoplasmic staining by standard in situ immunohistochemistry with antibodies for FGF-1, FGF-2, FGFR2, and FGFR3. RESULTS: Staining for FGF-1 is decreased or lost in the development of epithelial dysplasia and carcinoma. Staining for FGF-2 showed increased intensity (although not statistically significant) in oral epithelial dysplasias and squamous cell carcinomas and showed a significant increased expression in the upper layers of dysplasias and stratum spinosum-like cells in squamous cell carcinomas. Staining for FGFR2 showed a statistically significant increase in intensity in all layers of epithelial dysplasias and squamous cell carcinomas. Staining for FGFR3 was found in the upper stratum spinosum cells of normal and dysplastic epithelium and well-differentiated squamous cells in squamous cell carcinomas, with a statistically significant increase in staining intensity in dysplastic and carcinomatous tissues. CONCLUSIONS: The loss of FGF-1 is consistent with loss of differentiation in dysplasias and some squamous cell carcinomas. Changes in the localization of FGF-2 and FGFR2 into upper epithelial layers with increasing dysplasia suggest increased mitotic potential of high level cells. The co-localization of FGF-2 and its high affinity receptors in neoplastic tissues suggests an autocrine mechanism of influence on carcinogenesis.     

口腔鳞状细胞癌组织中Periostin的表达及其在上皮间质转化中的作用

目的:观察Periostin在口腔鳞状细胞癌组织中的表达情况,及其在上皮间质转化(EMT)中的作用。方法:用免疫组化法检测59例口腔鳞状细胞癌组织(实验组)和15例正常口腔黏膜组织(对照组)中Periostin、E-cadherin、Vimentin表达情况,分析Periostin与E-cadherin、Vimentin间相关关系。结果:59例口腔鳞状细胞癌组织中Periostin、E-cadherin、Vimentin阳性表达率分别为71.2%、52.5%、39.0%, Periostin表达与肿瘤TNM分期、分化程度、淋巴结转移密切相关(P＜0.05);且Periostin与E-cadherin表达降低和Vimentin表达上调间均存在相关性(P＜0.01)。结论:Periostin可能通过调控上皮间质转化促进口腔鳞状细胞癌侵袭转移。     

The expression of RAR beta mRNA in rat tongue carcinogenesis]

OBJECTIVE: To elucidate the relationship between the expression of nuclear retinoic acid receptor beta (RAR beta) mRNA in oral carcinogenesis and squamous cell aberrant differentiation. METHODS: A total of 69 rat tongue carcinogenesis specimens induced by 4-nitroquinoline-1-oxide (4NQO) were detected for RAR beta mRNA by in situ hybridization. RESULTS: With the progress of tongue carcinogenesis and epithelium cell disdifferentiation, the expression of RAR beta mRNA was down-regulated. The positive rate of RAR beta mRNA in normal, hyperplasia, mild-moderate dysplasia, severe dysplasia, in situ carcinoma and squamous cell carcinoma was 100.0%, 87.5%, 75.0%, 72.2%, 45.5% and 18.8%, respectively. CONCLUSIONS: The down-regulation of RAR beta mRNA may be associated with the epithelium cell aberrant differentiation and may be an important molecular mechanism of oral carcinogenesis.     

E-cadherin expression in normal, hyperplastic and malignant oral epithelium

E-cadherin is a calcium-dependent cell adhesion molecule which is important in cell-cell interactions in epithelium and plays a major role in maintaining the structure and integrity of epithelial sheets. The purpose of this study was to examine E-cadherin expression in normal and malignant oral epithelium. Ten specimens of normal oral epithelium, five specimens of hyperplastic epithelium and 15 squamous cell carcinomas were stained using a standard immunoperoxidase technique and a monoclonal antibody to E-cadherin. Normal and hyperplastic epithelium showed strong pericellular staining in the basal, suprabasal and prickle cell layers. The keratinising superficial layers were negative. E-cadherin expression did not correlate to the degree or pattern of keratinisation and was not altered in the hyperplastic epithelium. All cases of squamous cell carcinoma showed heterogenous staining with areas of loss or fragmentation of staining. No tumour was completely negative. The amount or pattern of loss showed no apparent correlation to the degree of tumour differentiation. These findings suggest that loss of E-cadherin is not essential for the acquisition of a malignant phenotype but may be important in the invasive process. This supports the view that E-cadherin may be the product of a tumour suppressor gene important in tumour progression.     

The presence of p53 protein in relation to Ki-67 as cellular proliferation marker in head and neck squamous cell carcinoma and adjacent dysplastic mucosa

Paraffin embedded material from 15 patients suffering from head and neck squamous cell carcinoma (NNSCC) bordered by dysplastic mucosal areas was immunohistochemically investigated for the presence of p53 protein and Ki-67 proliferation marker. p53 protein was present in 9 cases (60%), invariably in invasive cancer areas as well as in adjacent non-invasive dysplastic mucosa. Only cells exhibiting atypia contained p53 protein. Ki-67 proliferation marker was present in the basal cells of the normal epithelium and more extensive in dysplasias and HNSCC. The presence of Ki-67 closely coincided with p53 protein in the 9 cases exhibiting this. No differences in Ki-67 expression were found between p53 positive and negative cases. It is concluded that the appearance of p53 protein occurs early in carcinogenesis but that cells also may show increased proliferation without involving immunohistochemically detectable alterations in the p53 gene.