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1.
Oral mucosal lichen planus (OMLP) is a well recognized mucosal disease with unknown etiology. Considerable controversy exists as to whether OMLP is intrinsically premalignant, or if the disorder facilitates the development of oral mucosal squamous cell carcinoma (OMSCC) by external factors. The aim of the present study was to investigate the expression of c-erbB-2 protein in the keratinocytes of initial biopsies of oral mucosal disorders diagnosed as OMLP with no evidence of epithelial dysplasia. and to compare the results with the expression of c-erbB-2 protein in subsequent biopsies obtained from the same patients. These results were compared with the findings from control groups (patients with dysplasia with no evidence of OMLP, patients with OMSCC with no evidence of OMLP and normal oral mucosa). The expression of the c-erbB-2 protein was evaluated by immunohistochemical staining of the gene product with the avidin-biotin-complex method using paraffin-embedded tissue sections. Five of the initial biopsies from patients with OMLP expressed the c-erhB-2 protein and one did not. None of the OMLP cases that subsequently showed evidence of dysplasia expressed the c-erhB-2 protein, and of the three OMSCC specimens from the patients with OMLP. two were negative and one expressed c-erbB-2 protein. The specimens from the control groups all expressed the c-erhB-2 protein. The results indicated the probability of the absence of c-erbB-2 staining being an indication of a potential for neoplastic transformation in OMLP with dysplastic changes.  相似文献   
2.
Fos oncoprotein expression is a marker of neuronal activation following seizures. Here, using this method we examined the anatomical locations of muscimol-induced absence seizures in the rat forebrain. Six hours after a systemic injection of muscimol a massive Fos immunoreactivity appeared in the olfactory system, retrosplenial cortex and paraventricular thalamic nucleus, whereas other cortical areas contained low level of Fos expression. These results provide the first functional morphological evidence suggesting that these forebrain structures with Fos expression may play an important role in the pathophysiology of muscimol-induced absence seizures.  相似文献   
3.
将白细胞介素-1(IL)注入大鼠侧脑室,用Fos癌蛋白抗体免疫组化法检测了下丘脑室旁核的激活神经元:大量位于含促肾上腺皮质激素释放因子(CRF)相应区域的室旁核小细胞部神经元呈Fos免疫强阳性。Fos和CRF的免疫双染色显示了许多Fos免疫阳性神经元也呈CRF免疫阳性。此外,在IL-1注射动物中,CRF的免疫阳性显著加强,提示CRF合成增加。  相似文献   
4.
Thirteen sebaceous gland carcinomas and 10 sweat gland carcinomas were examined to elucidate any important histological parameters influencing their prognosis, and the relationship between immunohistochemical expressions of c-erbB-2 oncoprotein and survival of the patients was analyzed. Sebaceous gland carcinomas with vacuolated cytoplasm in more than 50% of whole tumor area, with necrosis, and without lymphoid cell infiltration in tumor nests and stroma had a higher incidence of tumor recurrence and tumor-related death than tumors with vacuolated cytoplasm in 50% or less of whole tumor area (p < 0.01), without necrosis, and with lymphoid cell infiltration in tumor nest and stroma (p < 0.05). Sweat gland carcinomas of all cases with fatal outcomes demonstrated tubular differentiation in 20% or less of whole tumor area, lymphatic permeation and desmoplastic reaction. Three sebaceous gland carcinomas and three sweat gland carcinomas were positive for c-erbB-2 oncoprotein. Two of three sebaceous gland carcinomas, and all three sweat gland carcinomas developed tumor recurrence and ended in tumor-related deaths. Sweat gland carcinomas with c erbB 2 expression had significantly shorter survival than those with negative immunostain (p < 0.01). Cytoplasmic appearance, tumor necrosis, and lymphoid cell infiltration in tumor nests and stroma of sebaceous gland carcinoma, and tubular differentiation, lymphatic permeation, and growth patterns of sweat gland carcinoma are considered to closely correlate to the prognosis. Immunohisto-chemically detected c erbB 2 oncoprotein may be an indicator of bad prognosis. Acta Pathol Jpn 42: 585–594, 1992.  相似文献   
5.
目的 探讨P53 及c -myc蛋白在食管癌及癌前病变中的表达及意义。方法 应用免疫组化SP法检测P53 及c -myc在 6 0例食管癌及 33例非典型增生中的表达。 结果 P53 及c -myc蛋白分别在食管癌与非典型增生I~II级中表达有显著差异 (P <0 .0 5 ) ;在食管癌与非典型增生III级表达中无显著差异 (P >0 .0 5 )。结论 P53 及c -myc蛋白异常表达 ,可为食管癌和癌前病变界限的划分提供参考依据。  相似文献   
6.
The Expression of the antiapoptotic oncoprotein BCL-2 and its correlation to tumor grade in 62 meningiomas (48 classic, 9 atypical, and 5 anaplastic) using single and double immunohistochemistry was investigated. BCL-2 expression was found in two different cell populations identified as lymphocytes (BCL-2+CD3+) and tumor cells (BCL+/CD3–). Tumor-infiltrating lymphocytes (TIL) (CD3+) were found within classic (9.5% of cells), atypical (2.4% of cells), and anaplastic (1.8% of cells) meningiomas. In classic meningiomas, 66.5% of TIL were BCL-2-positive, in atypical meningiomas 79.2%, and in anaplastic meningiomas 37.9%. In 33 (68.8%) of the classic meningiomas, medium to high counts of BCL-2+ tumor cells were detected. Atypical meningiomas showed nearly equal percentages of high (two patients), medium (five patients), and low (two patients) BCL-2+ tumor cell counts, whereas anaplastic meningiomas showed only medium (two patients) and low (three patients) BCL-2 tumor cell counts or were BCL-2-negative (one patient). In summary, a significant inverse correlation between the number of BCL-2-positive tumor cells and tumor grade in meningiomas was found. These findings support the hypothesis of cell survival prolongation by the antiapoptotic ability of BCL-2 proto- oncogenes and demonstrate the prognostic relevance of BCL-2 immunoreactivity in meningiomas. Received: 10 June 1998 / Accepted: 23 February 1999  相似文献   
7.
An increasing body of evidence connects alterations in the process of alternative splicing with cancer development and progression. However, a direct role of splicing factors as drivers of cancer development is mostly unknown. We analysed the gene copy number of several splicing factors in colon and lung tumours, and found that the gene encoding for the splicing factor SRSF6 is amplified and over‐expressed in these cancers. Moreover, over‐expression of SRSF6 in immortal lung epithelial cells enhanced proliferation, protected them from chemotherapy‐induced cell death and converted them to be tumourigenic in mice. In contrast, knock‐down of SRSF6 in lung and colon cancer cell lines inhibited their tumourigenic abilities. SRSF6 up‐ or down‐regulation altered the splicing of several tumour suppressors and oncogenes to generate the oncogenic isoforms and reduce the tumour‐suppressive isoforms. Our data suggest that the splicing factor SRSF6 is an oncoprotein that regulates the proliferation and survival of lung and colon cancer cells.  相似文献   
8.
9.
目的 探讨实时荧光定量PCR和RT-PCR检测HPV-16 E6和E7基因的实验方法.方法 将制备的含HPV-16 E6和E7基因的质粒作为标准品,建立实时荧光定量PCR和RT-PCR方法,分别对3种宫颈癌细胞株进行HPV-16 E6和E7基因的DNA和RNA拷贝数的定量检测.结果 建立的实时荧光定量PCR标准曲线相关系数大于0.99,PCR效率在90%以上.HPV-16 E6和E7基因的DNA和RNA拷贝数在宫颈癌细胞株 CaSki、SiHa和HeLa中从高到低依次是CaSki>SiHa>HeLa.结论 用实时荧光定量PCR和RT-PCR方法研究HPV-16 E6和E7基因的DNA和RNA含量结果可靠,为进一步研究两个基因与宫颈病变的关系奠定了基础.  相似文献   
10.
目的探讨p~(53)、C-erbB_2和ras癌基因蛋白产物在骨巨细胞瘤中的表达状况,了解该肿瘤的发病机制。方法应用免疫组化SP方法对50例骨巨细胞瘤进行p~(53)、C-erbB_2和p~(21)检测。结果50例骨巨细胞瘤均不表达p~(53)和C-erbB_2;ras癌基因蛋白产物p~(21)仅在部分骨巨细胞瘤病例中表达,阳性率为26%(13/50)。结论骨巨细胞瘤的发生可能与ras癌基因的活化有关。  相似文献   
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