Hyperplastic epithelial foci in honeycomb lesions in idiopathic pulmonary fibrosis

Seventy-two cases of idiopathic pulmonary fibrosis (IPF) were examined from 2856 consecutive autopsy cases at the Japanese Red Cross Medical Center in Tokyo from 1973-1996. Primary lung cancer had arisen in 31 of 72 cases of IPF (43%), significantly higher than the incidence in cases without IPF (8.1%) and in the cases with non-IPF chronic lung diseases (11.9%). Hyperplastic epithelial foci in the honeycomb lesions of IPF cases were significantly more prominent in the lower than in the upper lobe, in cases with or without lung cancer, and they were more prominent in the lower lobe of IPF with than in those without cancer. The length of hyperplastic epithelial foci in the lower lobe of IPF cases was longer than that in interstitial pneumonia-associated with collagen vascular diseases. There was a higher PCNA labeling index of hyperplastic epithelial foci in IPF cases than in cases of interstitial pneumonia-associated with collagen vascular diseases. The PCNA labeling index was almost the same between smokers and nonsmokers with IPF. Overexpression of p53 was observed in hyperplastic epithelial foci in honeycomb lesion of IPF. DNA ploidy analysis of hyperplastic epithelial foci in the paraffin sections of 12 IPF cases revealed aneuploidy patterns in eight cases. These results strongly suggest that accelerated cell proliferation occurs in the honeycomb lesion of IPF, and that regenerative epithelia becomes susceptible to carcinogenic agents in addition to the smoking effect.     

Genesis of squamous cell lung carcinoma. Sequential changes of proliferation, DNA ploidy, and p53 expression.

Squamous cell lung carcinomas (SCCs) represent a highly malignant group of tumors, and effective treatment is greatly dependent upon early diagnosis. However, objective diagnosis of atypia is difficult and useful markers need to be defined. In this study, genomic instability, cell proliferation, and cellular accumulation of mutant p53, as reflected by DNA aneuploidy, proliferating cell nuclear antigen, and p53 immunoreactivity, respectively, were evaluated in bronchial squamous metaplasia without atypia (n = 4), bronchial squamous metaplasia with low-grade atypia (n = 12), bronchial squamous metaplasia with high-grade atypia (n = 15), early-stage SCC (n = 15), and advanced-stage SCC (n = 33). Our results suggest that hyperproliferation is an early event followed by DNA aneuploidy, which in turn precedes p53 immunoreactivity in the genesis of SCC. We conclude that routine assessment of proliferating cell nuclear antigen, DNA ploidy, and p53 may be valuable for the early diagnosis of SCC.     

Incomplete expression of epithelial-mesenchymal transition markers in idiopathic pulmonary fibrosis

The hypothesis that epithelial-mesenchymal transition (EMT) contributes to the formation of fibroblast foci (FF), which are the histological hallmark and the site of active disease progression of Idiopathic Pulmonary Fibrosis (IPF), has not yet received a conclusive demonstration. Cells undergoing EMT lose epithelial features and acquire mesenchymal markers and morphology. Cadherin expression switch (from E to N) is one of the first events in EMT.We investigated the immunohistochemical expression of E- and N-cadherin, vimentin, fibronectin, laminin-5-γ2, α-smooth muscle actin, and fibroblast-specific protein-1 involved in EMT in 20 IPF lung biopsies, focusing on metaplastic squamous cells of bronchial basal origin, positive for laminin-5-γ2 and ΔNp63/p40, that cover FF. The results were compared with organizing pneumonia, reactive squamous cell metaplasia of bronchiolar epithelia, and squamous cell carcinoma.Bronchiolar basal metaplastic cells in IPF partially lost E-cadherin and expressed vimentin and fibronectin. Hyperplastic pneumocytes in IPF and controls coexpressed E-cadherin and N-cadherin, and were weakly positive for lam5-γ2. Reactive squamous cell metaplasia did not show any mesenchymal markers. Squamous cell carcinoma only expressed lam5-γ2.In IPF lungs, we observed two epithelial cell populations with a different expression profile of markers involved in EMT. Although neither hyperplastic pneumocytes nor bronchial basal cells showed evidence of complete EMT, only the latter seem to be specific for UIP and might have a role in its development.     

Epithelial abnormalities and precancerous lesions of anterior urethra in patients with penile carcinoma: a report of 89 cases.

Urethral and penile tissues and their neoplasms are considered anatomically and pathogenetically different. Since we observed urethral dysplastic lesions and some similarities between noninvasive and invasive lesions of the anterior urethra and glans, we designed this study to document epithelial urethral abnormalities in patients with penile squamous cell carcinoma. We examined urethral epithelia from 170 penectomies with invasive squamous cell carcinoma finding a variety of primary epithelial abnormalities in 89 cases (52%) and secondary invasion of penile carcinoma to urethra in 42 cases (25%). Patients' average age was 68 years. Primary tumors measured 4 cm in average diameter and the majority were squamous cell carcinoma of the usual (67%) or verrucous type (15%). Primary epithelial abnormalities found were squamous intraepithelial lesions, metaplasias and microglandular hyperplasias. Urethral squamous intraepithelial lesions of high grade was found in six patients and of low grade in eight cases. Squamous metaplasia, seen in 69 cases, was the most frequent finding. Metaplasias were classified as nonkeratinizing and keratinizing. Nonkeratinizing metaplasias (57 cases) were variegated in morphology: simplex (26 cases), hyperplastic (12 cases), clear cell (11 cases) and spindle (8 cases). Keratinizing metaplasias (12 cases) showed hyperkeratosis and were more frequently associated with verrucous than nonverrucous penile squamous cell carcinoma. Microglandular hyperplasia was present in eight cases. Lichen sclerosus was associated with simplex squamous metaplasia in four cases. Despite the large size of the primary tumors, direct urethral invasion by penile carcinoma was present in only 25% of the cases. The presence of precancerous lesions in urethra of patients with penile carcinoma indicates urethral participation in the pathogenesis of penile cancer. Simplex squamous metaplasia is a common finding probably related to chronic inflammation. Keratinizing and hyperplastic squamous metaplasias may be important in the pathogenesis of special types of penile carcinomas such as verrucous carcinoma.     

肺癌p53蛋白表达和基因突变与临床病理的相关研究

目的 检测肺癌中ｐ５３蛋白表达和基因突变状况及其与临床病理和预后的相关性。方法：应用免疫组织化学（ＬＳＡＢ法）和聚合酶链反应－单链构象多态性分析（ＰＣＲ－ＳＳＣＰ）二种方法。结果 检测肺鳞癌４６例，共９５例。免疫组化ｐ５３蛋白总阳性率为５０．５％（４８／９５例），肺鳞癌阳性率为５６．５％（２６／４６例）、肺腺癌为４４．７％（２２／４９例）。ＰＣＲ－ＳＳＣＰ检测ｐ５３基因突变率为４１．１％（３９／９     

Patterns of p53 mutations in squamous cell carcinoma of the lung. Acquisition at a relatively early age.

Squamous cell carcinoma (SQCC) of the lung is thought to arise after the accumulation of multiple mutations, including p53. To better characterize when p53 mutations are acquired, 37 SQCC of the lung were examined by polymerase chain reaction and single-strand conformation polymorphism analysis. Somatic p53 mutations were detected in nine tumors (24.3%). There were no significant differences in the stage, sex, or race between patients with or without p53 mutations. However, the patients with SQCC and p53 mutations were significantly (P = 0.0006) younger (mean age, 54.3 years) compared with patients without p53 mutations (mean age, 65). The topographical tissue distributions of the p53 mutations were examined by selective ultraviolet radiation fractionation. In all nine cases, the specific p53 mutant alleles were homogeneously present throughout the primary tumors, in all three examples with in situ carcinoma, and in all four cases with metastases. In one case, squamous metaplasia contiguous with the primary tumor also contained the same p53 mutation. Normal or hyperplastic and metaplastic or dysplastic epithelium not contiguous with the primary tumors lacked the specific p53 mutations. These findings suggest that p53 mutations are commonly acquired at a relatively early age, before the bulk of clonal expansion, and usually persist throughout the progression of SQCC of the lung.     

Diagnostic utility of cell cycle and apoptosis regulatory proteins in verrucous squamous carcinoma.

A major problem in the diagnosis of verrucous squamous cell carcinoma is the lack of readily reproducible objective criteria for distinguishing this malignant lesion from reactive epithelial hyperplasia. Both lesions are characterized by thickened (well-differentiated) squamous epithelium without cellular atypia and subjacent stroma densely infiltrated by lymphocytes and plasma cells. This study was carried out to evaluate the use of cell cycle and apoptosis-related regulatory proteins in the diagnosis of verrucous carcinoma. The study materials consisted of representative formalin-fixed and paraffin-embedded tissue blocks from 19 cases of verrucous carcinoma, 18 classic squamous cell carcinoma, and 14 squamous epithelial hyperplasia (acanthosis). The immunohistochemical expression of the following of cell cycle and apoptosis-related regulatory proteins was evaluated using avidin-biotin complex detection technique: p16, p21, p53, Ki67, and retinoblastoma gene product (RBGP) (also known as retinoblastoma protein [pRb]). Expression of Ki67 was detected only in the single basal layer of the epithelium in all 14 cases of acanthosis. In verrucous carcinoma, Ki67 was detected in basal and suprabasal cells in the lower third of the neoplastic epithelium in 19 of 19 cases (100%). In neoplastic squamous epithelium with frankly invasive squamous cell carcinoma, Ki67 was diffusely expressed throughout the entire thickness of the epithelium as well as in the underlying invasive tumor nests. The pattern of p53 expression was similar to that of Ki67 in all the experimental groups, with a Pearson correlation coefficient of 0.98. In addition, immunohistochemical expression of p53 in the hyperplastic squamous epithelium was very weak, in contrast to the more intense immunoreactivity observed in verrucous carcinoma and classic squamous cell carcinoma. There was an overlapping in the expression of p16, p21, and RGBP in all the experimental groups, being present in more than half the thickness of the epithelium in 50% to 100% cases in each study group. We therefore conclude that the pattern of Ki67 and p53 expression in verrucous carcinoma is readily reproducible and distinctly different from that observed in epithelial hyperplasia and that seen in invasive squamous cell carcinoma. Thus Ki67, and p53 immunostains are reliable adjuncts that may be helpful in resolving diagnostic problems associated with verrucous carcinoma.     

High frequency of coexpression of maspin with p63 and p53 in squamous cell carcinoma but not in adenocarcinoma of the lung

Maspin, a member of the serpin family of protease inhibitors, has been shown to inhibit tumor growth and suppress metastasis in several malignancies, including lung cancer. Previous studies have reported that p63 and p53 control maspin expression by transactivating the promoter. The present study analyzed immunohistochemical studies to determine the expression and coexpression patterns of maspin, p63 and p53 in non-small cell lung carcinoma, specifically squamous cell carcinoma and adenocarcinoma. The results showed that 83/86 cases (96.5%) of squamous cell carcinoma and 82/161 cases (50.9%) of adenocarcinoma included in this study were positive for maspin. There were 79/86 cases (91.9%) of squamous cell carcinoma and 16/161 cases (9.9%) of adenocarcinoma with positive expression for p63. In addition, 77/86 cases (89.5%) of squamous cell carcinoma and 99/161 cases (61.5%) of adenocarcinoma were positive for p53. Maspin, p63 and p53 expression were each significantly higher in squamous cell carcinoma than adenocarcinoma. Squamous cell carcinomas more highly coexpress maspin and p63, as well as maspin and p53, when compared with adenocarcinomas. The high frequency of coexpression of maspin and p63, as well as maspin and p53, in squamous cell carcinoma, suggests that p63 and p53 may be involved in the pathway to control maspin expression. Therapeutic targeting on maspin, p63 and p53 molecules might be beneficial in the management of patients with squamous cell carcinomas of the lung in the future.     

肺癌中P63与P53、E-cadherin、Ki-67表达的比较

目的　比较 p6 3及 p5 3、E cadherin(E cad)、Ki 6 7在肺癌中的表达 ,以了解在不同组织类型肺癌发生发展过程中 ,p6 3与抑癌基因 (p5 3)突变、上皮分化标志基因 (E cad)失活及细胞增殖标志基因 (Ki 6 7)激活有无相关性。方法　采用免疫组化S P法分别检测 6 1例原发性肺癌中 p6 3、p5 3、E cad和Ki 6 7的表达情况。 结果　p6 3在肺鳞癌中阳性率为 10 0 0 % ,而在其他组织类型肺癌中 p6 3基本不表达 ,差异有显著性 (P <0 0 5 ) ;在不同分化程度的肺鳞癌中 p6 3、p5 3的表达差异有显著性 (P<0 0 5 ) ,E cad、Ki 6 7的表达差异无显著性 (P >0 0 5 ) ;E cad的表达在小细胞肺癌与肺鳞癌和肺腺癌之间差异有显著性 (P <0 0 5 ) ;Ki 6 7的表达在各种组织类型肺癌之间差异有显著性 (P <0 0 5 ) ;在不同分化程度鳞癌中 p6 3与E cad的表达呈负相关(P <0 0 5 )。结论　p6 3可作为鳞状上皮源性肿瘤标记物 ,是判断鳞状细胞癌的增殖和分化有意义的指标 ,并可作为鉴别分化差的鳞癌和腺癌、小细胞癌的指标。     

Pulmonary fibrosis and lung carcinoma: a comparative study of metaplastic epithelia in honeycombed areas of usual interstitial pneumonia with or without lung carcinoma

Usual interstitial pneumonia (UIP), or idiopathic pulmonary fibrosis, has been considered to be associated with a high risk for lung carcinoma. To investigate this well-known but still equivocal relationship, we reviewed the clinical features of UIP autopsy cases with or without lung carcinoma (n = 32 and 38, respectively), and compared the morphology and cell kinetics of metaplastic epithelia in the honeycombed areas (n = 11, each group). Thirty-two of 70 UIP autopsy cases showed lung carcinomas. Clinically, UIP with lung carcinoma showed a male predominance (P = 0.001), a higher rate of smoking history (P = 0.001) and a later onset of UIP (P = 0.02), compared with UIP without lung carcinoma. Most of the carcinomas were peripheral in origin (90%), and 65% were topographically associated with honeycombed areas or the border between honeycombing and non-fibrotic areas. Quantitative assessment of the metaplastic epithelia in the honeycombed areas revealed that squamous metaplasia, but not cuboidal cell metaplasia or bronchial cell metaplasia, occurred more frequently in UIP with lung carcinoma than in UIP without lung carcinoma (P = 0.02). There were no significant differences between the two groups with regard to the labeling indexes of Ki-67 and p53 in the metaplastic epithelia, including squamous metaplasia. The degree of atypical squamous metaplasia was not different between the two groups. The quantitative predominance of squamous metaplasia in the honeycombed areas may not be a precursor for lung carcinoma, but might reflect a constitutional susceptibility of UIP patients to develop a lung carcinoma.     

Analysis of p53 tumor suppressor gene, H-ras protooncogene and proliferating cell nuclear antigen (PCNA) in squamous cell carcinomas of HRA/Skh mice following exposure to 8-methoxypsoralen (8-MOP) and UVA radiation (PUVA therapy)

Treatment with 8-methoxypsoralen (8-MOP) and ultraviolet radiation (primarily UVA), called PUVA therapy, has been used to treat different chronic skin diseases but led to a significant increased risk for skin cancer. The National Toxicology Program (NTP) performed a study in mice treated with PUVA that showed a significant increase in squamous cell carcinomas of the skin. In the present study, we evaluated the protein expression of p53 and PCNA and DNA mutations of p53 and H-ras genes in both hyperplastic and neoplastic squamous cell lesions from the NTP study. By immunohistochemical staining, protein expression of both p53 and PCNA was detected in 3/16 (19%) of hyperplastic lesions and 14/17 (82%) of SCCs in groups treated with both 8-MOP and UVA. The mutation frequency of p53 in SCCs from mice administered 8-MOP plus UVA was 15/17 (88%) with a predominant distribution of mutations in exon 6 (14/15 - 93%). No H-ras mutations were detected in the hyperplastic lesions/tumors. The mutagenic effect of PUVA on the p53 tumor suppressor gene may lead to a conformational modification and inactivation of the p53 protein, which are considered critical steps in PUVA-induced skin carcinogenesis. The p53 mutational frequency and patterns from our study were different from those reported in human PUVA-type tumors.     

Expression of p53 protein in precursor lesions and adenocarcinoma of human pancreas.

To evaluate the incidence and stage at which p53 alterations occur in human pancreatic carcinogenesis, we examined primary and metastatic carcinomas, carcinoma in situ, and hyperplastic lesions with and without atypia for p53 protein overexpression by immunohistochemical procedure. Overexpression of p53 was observed in 40% (10/25) of primary tumors, 29% (2/7) of metastatic tumors, 36% (5/14) of carcinoma in situ, and 35% (6/17) of hyperplastic lesions. These results suggest that p53 protein overexpression is not only a common genetic alteration but also occurs very early in the development of these tumors. It is suggested that p53 overexpression can be used as a marker to identify precursor lesions that have increased potential to develop into malignant tumors.     

Survivin expression in pre-invasive lesions and non-small cell lung carcinoma

Survivin is an inhibitor of apoptosis protein, which is overexpressed in many carcinomas, including lung carcinoma. The aim of this immunohistochemical study was to investigate the role of survivin in the early steps of lung carcinogenesis and non-small cell lung carcinomas (NSCLC), and its relationship with expression of p53 protein, a tumor suppressor gene involved in cell cycle control. In the normal bronchial epithelium, low-grade atypical adenomatous hyperplasia (AAH) and non-neoplastic lung parenchyma adjacent to tumor, survivin was found completely negative. Expression of survivin was detected in the areas of squamous metaplasia and dysplasia as well as high-grade AAH lesions adjacent to tumor. Survivin was expressed in 50 (64%) and p53 in 41 (53%) NSCLC. Survivin expression was significantly correlated with lymph node metastasis (p=0.02). There was no correlation between survivin and p53 expression. The patients with expression of survivin had significantly worse prognosis (Log-rank test, p=0.003). Multivariate Cox regression analysis showed TNM stage (p<0.001) and survivin expression (p=0.003) as independent prognostic indicators. In conclusion, survivin expression might be an early step in lung carcinogenesis. Survivin expression might also be used as a prognostic indicator predicting the worse outcome in NSCLC, and might be a novel target for the treatment of patients with preinvasive lesions of lung and NSCLC.     

Abnormal re-epithelialization and lung remodeling in idiopathic pulmonary fibrosis: the role of deltaN-p63

Products of the p63 gene, a recently described member of the p53 family, are constitutively expressed in the basal cells of human bronchi and bronchioli. The truncated isoforms of the p63 gene (deltaN-p63 proteins) counteract the apoptotic and cell cycle inhibitory functions of p53 after DNA damage, and this property is likely to be central in the cell renewal strategy of stratified epithelial tissues. To investigate the dysfunctional repair processes that characterize idiopathic pulmonary fibrosis/usual interstitial pneumonia (IPF/UIP), we immunohistochemically analyzed the expression of the transactivating and dominant-negative isoforms of the p63 gene on 16 tissue samples obtained from patients suffering from this disorder. In most IPF cases herein investigated, epithelial cells expressing deltaN-p63 were observed at sites of abnormal proliferation at the bronchiolo-alveolar junctions, characterized by epithelial hyperplasia, squamous metaplasia, bronchiolization, and abnormal p53 nuclear accumulation. Similar features were not observed in normal lung and in samples taken from other pulmonary diseases used as controls, including acute interstitial pneumonia, idiopathic bronchiolitis obliterans organizing pneumonia, nonspecific interstitial pneumonia, and desquamative interstitial pneumonia. On the basis of these findings, we can hypothesize a new model for UIP pathogenesis, involving a deregulated development of mesenchymal-epithelial interactions and abnormal proliferation of epithelial cells at the bronchiolo-alveolar junction after cell injury. In our view, the progressive loss of alveolar tissue and lung remodeling after injury in IPF/UIP is concomitantly produced by pneumocyte loss and alveolar collapse on one hand and by progressive bronchiolar proliferation and architectural distortion on the other.     

Co-expression of endothelial cell and macrophage antigens in Kaposi's sarcoma cells

Mutations in the p53 tumour suppressor gene, with consequent accumulation of the p53 protein, are frequently observed in non-small cell lung cancer (NSCLC). Little is known, however, about the timing of their appearance or their maintenance through cancer progression and metastatic spread. We have examined the normal epithelium and a panel of bronchial lesions, including dysplastic, neoplastic, and metastatic leisons, for p53 immunoreactivity and for expression of proliferating cell nuclear antigen (PCNA). No p53 immunoreactivity was found in normal and hyperplastic epithelium, nor in squamous metaplastic lesions. Twenty out of 30 invasive tumours and 13 out of 17 in situ carcinomas adjacent to an invasive tumour showed p53 immunoreactivity. There was a strict correlation between the level of p53 expression in the non-invasive and the invasive components of the tumours. Five out of eight pairs of primary tumours and matching metastases expressed p53, at identical levels in both compartments. These data indicate that p53 overexpression can occur in the earliest recognized phase of NSCLC and that the alteration is maintained during progression from in situ to invasive carcinoma and metastatic spread. PCNA expression increased from early to advanced phases of NSCLC. High PCNA immunoreactivity was observed in tumours expressing high p53 levels. A significant association was observed for PCNA expression between preinvasive and invasive lesions.     

Apocrine adenosis: a precursor of aggressive breast cancer?

AIM--To investigate overexpression of c-erbB2, expression of the p53 protein product and proliferation rates in benign breast lesions with specific reference to apocrine adenosis. METHODS--Twenty one cases of apocrine adenosis were stained with monoclonal antibodies to p185, the protein product of the c-erbB2 oncogene, the protein product of the p53 tumour suppressor gene and to the cell cycle related protein Ki67. Three cases were associated with concomitant ductal carcinoma in situ of large cell type and two were associated with invasive tubular or cribriform carcinoma. RESULTS--Twelve (57.1%) cases showed membrane staining for c-erbB2 oncoprotein of apocrine cells within sclerosing adenosis and six (28.6%) had occasional p53 protein positive cells. One case not associated with carcinoma showed extensive staining of apocrine metaplasia outside the area of apocrine adenosis. The proliferation rate, as measured by Ki67 staining, was increased in some of the lesions and all lesions showed at least some of the cells to be in the cell cycle. CONCLUSIONS--The expression of abnormal oncogene products and increased proliferation in some of these apocrine lesions questions the supposed degenerative nature of the atypia seen in such cases and suggests that there may be an association between these lesions and large cell ductal carcinoma in situ and hence invasive carcinoma.     

Alveolar epithelial cells in idiopathic pulmonary fibrosis display upregulation of TRAIL,DR4 and DR5 expression with simultaneous preferential over-expression of pro-apoptotic marker p53

Idiopathic pulmonary fibrosis (IPF) is a progressive, debilitating, and fatal lung disease of unknown aetiology with no current cure. The pathogenesis of IPF remains unclear but repeated alveolar epithelial cell (AEC) injuries and subsequent apoptosis are believed to be among the initiating/ongoing triggers. However, the precise mechanism of apoptotic induction is hitherto elusive. In this study, we investigated expression of a panel of pro-apoptotic and cell cycle regulatory proteins in 21 IPF and 19 control lung tissue samples. We reveal significant upregulation of the apoptosis-inducing ligand TRAIL and its cognate receptors DR4 and DR5 in AEC within active lesions of IPF lungs. This upregulation was accompanied by pro-apoptotic protein p53 overexpression. In contrast, myofibroblasts within the fibroblastic foci of IPF lungs exhibited high TRAIL, DR4 and DR5 expression but negligible p53 expression. Similarly, p53 expression was absent or negligible in IPF and control alveolar macrophages and lymphocytes. No significant differences in TRAIL expression were noted in these cell types between IPF and control lungs. However, DR4 and DR5 upregulation was detected in IPF alveolar macrophages and lymphocytes. The marker of cellular senescence p21^WAF1 was upregulated within affected AEC in IPF lungs. Cell cycle regulatory proteins Cyclin D1 and SOCS3 were significantly enhanced in AEC within the remodelled fibrotic areas of IPF lungs but expression was negligible in myofibroblasts. Taken together these findings suggest that, within the remodelled fibrotic areas of IPF, AEC can display markers associated with proliferation, senescence, and apoptotosis, where TRAIL could drive the apoptotic response. Clear understanding of disease processes and identification of therapeutic targets will direct us to develop effective therapies for IPF.     

p53蛋白堆积和CK-18neo在非小细胞

目的:检测非小细胞肺癌组织的p53蛋白堆积水平和细胞骨架蛋白18新抗原决定簇(cytokeratin18neo-epitope,CK-18neo)的暴露情况,探讨p53蛋白和CK-18neo在肺癌发生发展过程中的作用及其临床病理意义。方法:用免疫组化法检测62例非小细胞肺癌以及10例对照组织中p53蛋白的堆积和CK-18neo的暴露情况。用显微图象分析仪测定p53免疫组化反应的强度,并作定量分析。以凋亡指数(AI%)表示CK-18neo的阳性检出率。结果:①非小细胞肺癌组织中p53的阳性检出率为48.39%(鳞癌为51.72%,腺癌为45.45%),对照组p53的阳性率为0.00%(P＜0.01);②非小细胞肺癌组织的AI%为1.10%(鳞癌0.95%,腺癌1.24%),对照组为1.06%,各组间无显著差异;③非小细胞肺癌组织中p53(-/+)、p53(5级)和p53(PU)呈正直线相关关系(P＜0.01)。结论:本实验结果提示,突变型p53基因可能参与NSCLC的发生机制,NSCLC的发生和发展与癌细胞的过度增生和细胞凋亡减少有关。     

用显微切割技术定点检测诱发大鼠肺癌发生发展各阶段p53、K-ras基因突变与表达

目的　探讨p5 3、K ras基因突变、蛋白表达在 3 甲基胆蒽 (3 methylcholanthrene ,MCA)和二乙基亚硝胺 (diethylinitrosamine ,DEN)诱发大鼠肺鳞癌发生演进中的作用 ,及其突变与蛋白表达的关系。方法　将大鼠诱发肺癌石蜡标本连续切片 ,切片用于HE染色确定肺癌发生发展的病变阶段 ,及免疫组织化学 (SP法 )检测各阶段p5 3、K ras蛋白表达 ,并用于显微切割 ,定点对位分别切割由正常支气管黏膜上皮细胞演变成癌细胞 ,癌浸润、转移各阶段病灶的主质 ,提取DNA ,用聚合酶链反应 单链构象多态性 (PCR SSCP)检测各阶段p5 3、K ras基因的突变。结果　 30例正常支气管黏膜上皮未检测到p5 3、K ras基因突变及其蛋白表达。在 32例支气管黏膜增生和鳞状化生、2 1例不典型增生、12例原位癌、4 3例浸润癌及 17例转移癌组织中 ,p5 3基因突变率分别为 3 1% ,2 8 6 % ,30 0 % ,5 1 2 % ,5 2 9% ;p5 3蛋白阳性表达率分别为 0 ,4 2 9% ,5 0 0 % ,6 0 5 % ,6 4 7% ;不典型增生阶段与增生、鳞状化生阶段相比 ,p5 3基因突变率及蛋白表达率增高 ,差异均有显著性意义 (P <0 0 2 5 ,P <0 0 0 5 ) ,p5 3基因突变及蛋白阳性表达高度相关 (P <0 0 0 5 ,Pearson′sR =0 5 996 )。K ras基因突变率分别为 0 ,4 8% ,8 3% ,9 3     

p53 protein expression in malignant, pre-malignant and non-malignant lesions of the lip.

AIM: To elucidate the role of the p53 tumour suppressor gene in the pathogenesis of lip cancer. METHODS: Expression of p53 was evaluated immunocytochemically in a retrospective study of formalin fixed, paraffin wax embedded tissue. Five cases each of four types of lip lesions were studied; these comprised squamous cell carcinoma (SCC), solar keratosis (SK), chronic hyperplastic candidosis (CHC), and lichen planus (LP). Five cases each of normal lip mucosa, SCC, and SK from sun exposed facial skin as well as LP, CHC, and SCC from buccal mucosa were also analysed. Immunolocalisation of p53 was scored semiquantitatively. The degree of apoptosis was also assessed in selected lesions by determining cell nuclear fragmentation. RESULTS: All SCCs from lip lesions were immunopositive for p53. All cases of SK and two of five CHC lip lesions were also p53 positive. Normal lip mucosa samples were p53 negative. Sun exposed skin lesions of SCC and SK were all positive for p53, but only three of five cases of SCC from the buccal mucosa had detectable levels of p53. p53 expression was not detected in CHC and LP lesions of the buccal mucosa. CONCLUSIONS: The aberrant expression of p53 is likely to occur early in the pathogenesis of lip cancer and may be related to exposure to the sun. The immunopositive p53 cells identified in the benign LP lesions do not necessarily correlate with commitment of cells within the lesion to programmed cell death. In light of the prior reports which indicate that p53 positive cells may progress to form malignant tumours, it is suggested that patients with p53 positive but otherwise benign lesions should be followed more closely.