p53蛋白在宫颈鳞癌组织中的表达及意义

目的探讨p53蛋白在宫颈鳞癌组织中的表达及临床意义。方法应用免疫组化SP法分别对宫颈鳞癌切除标本和正常宫颈组织标本中的p53蛋白的表达状况进行检测。结果 p53蛋白在35例正常组织中不表达,在65例宫颈鳞癌组织中,p53蛋白阳性表达38例,阳性率为58.46%。癌组织中p53蛋白的表达率与正常组织比较差异有统计学意义（P〈0.05）。p53蛋白的阳性表达率与年龄及临床分期差异无统计学意义（P〉0.05）,即p53蛋白表达阳性与宫颈鳞癌患者年龄及临床分期无明显相关。p53蛋白的表达量与宫颈鳞癌的分化程度及局部淋巴结转移差异有统计学意义（P〈0.05）,即p53蛋白的表达量与病理分化程度及局部淋巴结转移有关。结论 p53蛋白的表达与宫颈鳞癌的发生发展有关,可作为宫颈鳞癌的早期诊断、治疗及预后评估的一项参考指标。     

宫颈鳞状细胞癌HPV16/18、p53、p21表达及意义

目的　探讨人乳头状瘤病毒 (HPV) 16型、18型及 p5 3、p2 1基因蛋白的表达情况以及与宫颈癌的关系。 方法　应用免疫组化二步法检测 5 0例宫颈鳞癌、4 0例正常宫颈黏膜中HPV16、HPV18、p5 3、p2 1的表达。肿瘤组分 <6 0岁和≥ 6 0岁 2个年龄组 ,观察HPV感染情况。结果　宫颈鳞癌中HPV16、HPV18、p5 3、p2 1表达分别为 4 8%、2 0 %、5 4 %和 5 0 % ,而正常宫颈黏膜中的表达分别为 10 %、0、0、10 % ,两者经统计学比较差异有显著性 (P <0 0 1) ;<6 0岁组和≥ 6 0岁组HPV16阳性率分别为 84 2 %和 2 5 8% ,年青组明显高于年老组 ,经统计学比较差异有显著性 (P <0 0 1)。结论　 (1)宫颈鳞癌的发生与HPV16、HPV18感染有密切关系 ,提示检测宫颈HPV16、HPV18感染情况对于宫颈鳞癌的随访和早期诊断有着重要的参考价值。 (2 )提示宫颈黏膜在HPV感染后 ,可能在p5 3、p2 1多种癌基因的共同作用导致宫颈鳞癌的发生发展。     

Variations in immunohistochemical detection of p53 protein overexpression in cervical carcinomas with different antibodies and methods of detection

Immunocytochemical detection of p53 protein products in paraffin sections is possible with a number of antisera, monoclonal and polyclonal. Few corroborative results amongst different laboratories have been published due to variations in the antibodies, the fixation protocols, and the immunocytochemical methods applied. Antigen unmasking methods employing microwaves or proteolytic enzymes add to the disparity in the percentage of positive cases reported. In this study, paraffin sections of 55 cases of cervical carcinoma were immunostained with monoclonal antibodies p53-DO7 and p53-1801 (a) without section pretreatment, (b) with pronase digestion, and (c) with microwave antigen retrieval in citric acid buffer. Specimens fixed in buffered formalin required antigen unmasking to show positive staining. Pronase digestion caused false-negative immunostaining. Microwave pretreatment with p53-DO7 yielded 100 per cent positivity for p53 proteins but only 7/55 cases with more than 50 per cent positive cells. Monoclonal antibody p53-DO7 detected more positive cases than p53-1801. Immunostaining with antibodies to p53 proteins must be interpreted cautiously as variations in fixation, antibodies, and section pretreatment will significantly affect results.     

Codon 72 polymorphism of p53 and HPV type 16 E6 variants as risk factors for patients with squamous epithelial lesion of the uterine cervix

The Arg/Arg genotype versus Arg/Pro or Pro/Pro at codon 72 of the p53 gene in association with human papillomavirus (HPV) 16 E6 variants has been implicated as a risk marker in cervical neoplasia. However, research on this topic has produced controversial results. The association of p53 codon 72 polymorphism alone and in combination with specific HPV 16 E6 variants with risk of developing squamous intraepithelial cervical lesion has been investigated in low and high‐grade squamous intraepithelial lesions and in HPV‐negative controls from an Italian population. The data obtained showed statistically significant different distribution of p53 genotypes between healthy controls and precursor lesions, with the p53 arginine homozygous increased in high‐grade squamous intraepithelial lesions. The T350G HPV 16 variant was the most frequent variant observed in the analyzed group of Italian women, showing a slight decreasing with the severity of the lesion. At the same time, the number of the prototype T350 slightly increased with the severity of the cytological lesions. In conclusion, p53 arginine homozygous was found to be increased in high‐grade lesions, supporting the results of previous investigations indicating that HPV‐positive patients with p53 Arg/Arg have an increased risk of developing pre‐cancerous lesions. In addition, T350G HPV 16 variant was over‐represented in p53 Arg homozygous women with cervical lesions. When p53 genotype and HPV 16 variants are considered together, no difference emerges between cases and controls so is not possible to assess that the oncogenic effect of HPV 16 T350G variant may be influenced by the p53 genotype. J. Med. Virol. 85:83–90, 2012. © 2012 Wiley Periodicals, Inc.     

Expression of p53 in oesophageal squamous epithelium from surgical specimens resected for squamous cell carcinoma of the oesophagus,with special reference to uninvolved mucosa

Accumulation of p53 protein has been considered an intermediate biomarker in multistage oesophageal carcinogenesis. The aim of the present study was to investigate p53 expression by immunohistochemistry in 13 thoroughly sampled oesophagectomy specimens from a geographical area with a high oesophageal cancer incidence (Basse Normandie, France). Expression of p53 was looked for in tissue samples of cancer, intraepithelial neoplasia, and uninvolved mucosa. The streptavidin biotin peroxidase complex method was used for p53 immunostaining. p53 expression was found in invasive squamous cell carcinoma in 8 out of 11 cases and in intraepithelial neoplasia in 10 out of 11 cases. In all 13 cases, in uninvolved oesophageal mucosa, expression of p53 was focally present in areas of chronic oesophagitis. Chronic oesophagitis has been regarded by epidemiologists as a precursor lesion for squamous cell carcinoma of the oesophagus. Since oesophageal carcinogenesis is a multistage process, the study of precursor lesions could provide information on the timing of p53 gene abnormalities during oesophageal carcinogenesis. These preliminary data require to be confirmed by molecular analysis of the p53 gene. © 1997 John Wiley & Sons, Ltd.     

Immunoreactivity for p53 protein in malignant mesothelioma and non-neoplastic mesothelium.

The presence of p53 protein in non-neoplastic pleural mesothelium (40 cases) and in human malignant mesothelioma (36 cases) was assessed immunohistochemically using the antibodies DO7, CM-1, and PAb240. In a quarter of the malignant mesotheliomas, there was nuclear immunoreactivity for p53 protein with both the DO7 and CM-1 antibodies. There were no statistically significant differences between the various mesothelioma subtypes (P > 0.05). No immunoreactivity was found with the PAb240 antibody, suggesting absence of mutant-type p53 protein. Nonneoplastic mesothelium was not immunoreactive with any of the antibodies. We conclude that there is immunoreactivity for p53 protein in some mesotheliomas. p53 protein immunoreactivity could be used to discriminate between neoplastic and reactive mesothelium.     

p53 Protein expression in laryngeal squamous cell carcinomas bearing wild-type and mutated p53 gene

We performed an immunohistochemical analysis to investigate the expression of p53 protein in a panel of 18 laryngeal squamous cell carcinomas, 15 primary tumours and three in relapse, previously analysed by us for the presence of p53 gene mutations. Dysplastic and/or normal surrounding mucosa was evaluated in 15 different tumours. The results of our study are the following: (1) expression of p53 protein was observed in one out of five tumours positive for p53 gene mutations (20%) and in 10 out of 13 (80%) negative cases; (2), p53 protein over-expression was frequently observed in normal and/or dysplastic mucosa surrounding either wild-type (7/11) or mutated p53 tumours (2/4); (3), p53 immunoreactive cells showed a pattern of distribution in normal and mildly/moderately dysplastic mucosa (basal layers), different from that in severely dysplastic mucosa (whole thickness). These data further support the hypothesis that p53 protein over-expression may be a marker of the earliest phases of multistep tumorigenesis in laryngeal squamous cell carcinoma.     

p53 expression in normal,dysplastic, and neoplastic laryngeal epithelium. Absence of a correlation with prognostic factors

p53 expression has been examined in 89 squamous cell carcinomas of the larynx (34 glottic, 28 supraglottic, 18 transglottic, 8 pyriform sinus, and 1 subglottic) obtained from 88 patients surgically treated in our centre. In addition, 59 laryngeal samples including normal respiratory epithelium and non-invasive squamous cell lesions were also tested. Frozen sections were immunostained with PAb 1801 and the results were correlated with pathological features, DNA ploidy and S-phase of the tumours, disease-free interval, and survival of the patients. p53 immunoreactivity was observed in 57 (64 per cent) carcinomas. None of the eight samples of normal respiratory epithelium was positive. p53-positive cells were seen in 8 of 23 (35 per cent) squamous cell metaplasias, 6 of 19 (32 per cent) low-grade dysplasias and 5 of 10 (50 per cent) high-grade dysplasias. No correlation was found between p53 expression in carcinomas and their clinical and pathological characteristics, DNA ploidy, or proliferative activity. Neither disease-free nor overall survival showed differences between p53-positive and p53-negative cases. These findings indicate that p53 may play a role in an early stage of malignant transformation of a subset of squamous cell carcinomas of the larynx, but seems not to be associated with further progression of the tumours.     

Interpretation of p16, p53 and mismatch repair protein immunohistochemistry in gynaecological neoplasia

Current management of gynaecological neoplasms is underpinned by their molecular characteristics. For many neoplasms the underlying genetic abnormalities can be reliably detected using immunohistochemistry for protein expression as a surrogate. The three most widely utilized biomarkers in this regard in gynaecological neoplasms are p16, p53 and mismatch repair (MMR) proteins, and it is vital for all pathologists to be aware of the indications for their use, correct interpretation of expression patterns, awareness of technical and interpretive pitfalls as well as appropriate reporting terminology.     

Aberrant expression of the tumour suppressor gene p53 is very frequent in Wilms' tumours.

A series of 34 Wilms' tumours have been analysed for abnormal expression of the tumour suppressor gene p53 using frozen section immunohistochemistry. All tumours showed immunoreactivity with at least one of the specific antibodies used (monoclonal antibody PAb240, polyclonal antibodies CM1 and JG8). Abnormalities of p53 expression are very frequent in this type of childhood tumour.     

p53 expression in CMV-infected cells: association with the alternative expression of the p53 transactivated genes p21/WAF1 and MDM2

The p53 tumour suppressor gene is a cell cycle regulator, able to induce cell cycle arrest to allow DNA repair or apoptosis. The molecular mechanisms underlying p53 action imply transactivation of p53 dependent genes such as WAF1 (for wild type p53 associated fragment 1) and the murine double minute (MDM2) gene. In some cases, inactivation of the p53 gene results from p53 gene mutations leading to p53 protein accumulation, but in others it may results from mechanisms other than mutation, such as interaction with viral or cellular proteins. The expression of p53 protein and p53 transactivated gene proteins p21/WAF1 and MDM2, combined with in situ detection of apoptosis, was studied in specimens of CMV-infected patients as an in vivo model of p53 alteration not due to point mutation. p53 positivity was found in CMV + cells in different tissues, in cells with typical inclusion bodies, and in in situ hybridization and immunohistochemistry CMV + cells without inclusions (hidden infection). Although this p53 reactivity was accompanied by the expression of MDM2 and p21/WAF1 proteins, the patterns of MDM2 and p21/WAF1 protein expression were mutually exclusive, and were associated with the presence or absence of inclusion bodies. Nuclei bearing inclusion bodies were usually MDM2 +, p21/WAF1?, while hidden infected cells were usually MDM2?, p21/WAF1 +. Apoptosis was not detected in any tissue section from CMV-infected patients. Two alternative patterns were found in CMV-infected tissues: p53 +, p21/WAF1 +, MDM2?, or p53 +, p21/WAF1?, MDM2 + protein expression. These may represent examples of p53 dependent alternative effects in the course of CMV infection. Early stages are represented by CMV + cells without inclusion bodies, which display p53 and p21/WAF1 expression, suggesting that p53 could be acting as a growth suppressor protein. Late CMV infection is represented by cells harbouring inclusion bodies. These cells showed a p53 +, p21/WAF1?, MDM2 + profile, consistent with MDM2 mediated p53 inactivation. The absence of p21/WAF1 expression and lack of apoptosis suggest that the p53 protein expressed by MDM2 + cells could be functionally inactivated in CMV-infected cells with inclusion bodies. Previous studies have suggested that p53 inactivation by MDM2 over-expression occurs in sarcomas and lymphomas. Our observations seem to indicate that this mechanism of MDM2 mediated p53 inactivation may play a role in the late phase of CMV infection.     

Immunohistochemical localization of syndecan-1 in normal and pathological human uterine cervix

Expression of syndecan-1, a cell surface proteoglycan that binds growth factors and extracellular matrix components, was studied in normal and pathological human uterine cervix using immunohistochemical methods. Normal cervical squamous epithelium showed positive staining for syndecan-1 in all cell layers, except the basal cell layer, whereas endocervical columnar epithelium stained weakly. In non-neoplastic reactive lesions, metaplastic squamous cells were positive for syndecan-1, whereas columnar cells showed weak or negative staining. In cervical condylomas, cells showing koilocytotic atypia were positive for syndecan-1. The progression of cervical intraepithelial neoplasia (CIN) grade I to grade III was associated with reduced syndecan-1 expression and localization of syndecan-1 to more superficial cell layers. In squamous cell carcinomas (SCCs), syndecan-1 expression correlated with histological differentiation, being absent from most poorly differentiated tumours. The results suggest that loss of syndecan-1 from atypical cells is an early event during cervical carcinogenesis and show a close association of syndecan-1 expression with preserved epithelial morphology and differentiation.     

Association of p53 expression with prognosis in patients with esophageal squamous cell carcinoma

It has been well accepted that p53 overexpression is associated with advanced stages of cancer. However, the prognostic role of p53 overexpression in esophageal squamous cell carcinoma (ESCC) remains unclear. To investigate the prognostic role of p53 overexpression in patients with ESCC, a retrospective cohort study of 136 ESCC patients was carried out. The expression of p53 protein in tumor tissues was investigated immunohistochemically. Positive expression of p53 protein was detected in 57 ESCC patients (41.9%). The p53 overexpression was associated with smoking (P < 0.001), tumor differentiation (P < 0.001), and tumor size (P < 0.001). In the Kaplan-Meier analysis, patients with p53 overexpression had significantly shorter overall survival than those patients with negative p53 expression (log-rank P < 0.001). Multivariable analysis by Cox regression model further showed that p53 overexpression was a significantly independent predictor of poorer overall survival (hazard ratio [HR] = 1.91; 95% confidence interval [95% CI] 1.03-3.54, P = 0.04). Thus, p53 overexpression is associated with poor prognosis in patients with early stage esophageal squamous cell carcinoma, and it’s a significantly independent predictor of poorer overall survival.     

c-myc和p53蛋白在宫颈癌组织中的表达及临床意义

目的探讨c myc和p53蛋白在宫颈癌中表达的临床意义。方法采用免疫组化法检测51例正常宫颈、宫颈上皮内瘤样病变(CIN)和宫颈鳞癌中的c myc和p53蛋白的表达,并用TUNEL法检测细胞凋亡数。结果正常宫颈c myc和p53未见表达,宫颈鳞癌c myc和p53表达高于CIN(P<0.05)。宫颈鳞癌和CIN的TUNEL标记率均低于正常宫颈,宫颈鳞癌与CIN及正常组比较相差非常显著(P<0.01)。结论细胞凋亡可能与宫颈癌的形成过程有关,c myc和p53蛋白过度表达在宫颈癌的发生发展中起很重要的作用。     

Immunoreactivity for p53 and mdm2 and the detection of p53 mutations in human malignant mesothelioma

Previous immunohistochemical studies on malignant mesothelioma with antibodies recognizing both the wild and the mutant types of the p53 protein have shown immunoreactivity in 25–70% of cases. This study was designed to determine whether there is immunoreactivity for p53 and mdm2 protein in malignant mesothelioma and to correlate p53 expression with the detection of mutations in p53 at DNA level. In 10 of 15 cases there was immunoreactivity for p53. In 6 of these cases immunoreactivity for mdm2 was also detected. In one p53-immunonegative case, a mutation of the p53 gene resulting in a stop codon was found. These results suggest that mdm2 might be involved in the inhibition of p53 in malignant mesothelioma. Also, these data suggest the existence of other proteins than mdm2 that may associate with p53.This work was supported by the Belgian Cancer Association (Vereniging voor Kankerbestrijding) and the Flemish Biotechnology Programme of the Ministry of Economy     

Significance of p53 expression as a prognostic factor in oesophageal squamous cell carcinoma

The tumour suppressor gene product p53 is believed to play an important role in the progression of human malignant tumours through mutation and over-expression. Using a microwave oven heating method, we have detected over-expression of p53 in buffered-formalin fixed, paraffin-embedded sections of oesophageal carcinomas immunohistochemically and examined the relationship between the p53 over-expression and postoperative survival. Employing a monoclonal antibody (pAb1801), nuclear p53 was detected in 56 of 105 (53%) tumour specimens. Homogeneous, heterogeneous, and focal immunostaining patterns were noted. No immunostaining was found in adjacent benign tissues. The results in buffered-formalin fixed sections were similar to those in the frozen sections. The cumulative survival rate of patients with p53 expression was significantly lower than that of the patients without expression (P<0.05), even though there were no significant differences between the clinicopathological features of the two groups. The results indicate that the nuclear accumulation of p53 might be an independent prognostic factor in patients with oesophageal squamous cell carcinomas.     

p53基因第72位密码子多态性与宫颈癌相关性

目的　探讨 p5 3基因第 72位密码子多态性与新疆汉族人群宫颈癌发生的关系。 方法　采用限制性酶切片段多态性分析 (RFLP)技术检测 72例宫颈癌及正常宫颈石蜡包埋组织中p5 3基因多态性的分布 ,分析两者之间的相关性。结果　p5 3基因 3种基因型Arg/Arg、Pro/Pro、Pro/Arg在宫颈癌中所占比例分别是 2 1 0 % ,39 5 % ,39 5 % ,对照组为 38 2 % ,14 7% ,4 7 1% ,两组总构成比差异有显著性 (χ2 =6 0 1,P <0 0 5 ) ,Pro/Pro在宫颈癌中所占比例高于对照组 ,没有发现Arg/Arg在宫颈癌中所占比例高于对照组 ,在HPV16、18阳性宫颈癌中所占比例分别是 2 2 2 % (4 /18)、5 0 0 % (9/18)、2 7 8% (5 /18) ,Pro/Pro所占比例明显高于其它两型。结论　p5 3Pro/Pro基因型可能是新疆汉族女性宫颈癌主要遗传易感因素。     

Immunohtstochemical analysis of the p53 oncoprotein on paraffin sections using a series of novel monoclonal antibodies

Alterations of the p53 tumour suppressor gene are considered critical events in multistage carcinogenesis of a wide range of human cancers. In an attempt to elucidate the role of various p53 mutations in tumorigenesis and to investigate their relationship to the p53 protein accumulation and subcellular localization, we have raised a new series of 21 mouse monoclonal antibodies (MAbs) to human recombinant p53. The new MAbs (designated the Bp53 series) appear to recognize mainly denaturation-resistant epitopes in immunoblotting and the majority of them are suitable for immunostaining of p53 in cultured cells and frozen sections. Furthermore, at least three MAbs (Bp53-11, Bp53-12, and Bp53-28) proved to be reliable reagents for immunohistochemistry on paraffin-embedded specimens. The immunohistochemical analysis of paraffin sections from 118 human tumours of various histogeneses with Bp53-11 and Bp53-12 showed nuclear accumulation of the p53 protein in variable proportion of tumour cells in 76 cases (64 per cent). The influence of three parameters of tissue processing (type of fixative, period of fixation, and duration of autolysis) on p53 protein detection was also investigated. The results of this study provide the necessary basis for wider application of these novel MAbs as tools in both routine hisiopathology and functional analyses of the p53 oncoprotein.     

口腔鳞癌及癌前病变组织中p27、p53蛋白的表达

目的　探讨 p2 7、p5 3蛋白表达在口腔鳞癌发生发展中的意义。 方法　应用免疫组化S P法分别检测 9例口腔正常黏膜 ,11例单纯性增生、2 6例癌前病变及 5 4例鳞癌组织中p2 7、p5 3蛋白的表达。 结果　p2 7蛋白在口腔正常黏膜和单纯性增生组织中呈高表达 ,在癌前病变和鳞癌组织中高 (低 )表达率分别为 6 1 5 % (38 5 % )、2 5 9% (6 1 1% ) ,在鳞癌中阴性表达率为 13% ;p2 7蛋白的表达与鳞癌的组织分化程度、临床分期相关 (P <0 0 5 )。p5 3蛋白在正常黏膜、单纯性增生及轻、中度不典型增生中未见表达 ,在重度不典型增生和鳞癌中可见 2 8 6 %和 4 8 1%的阳性表达 ,二者差异有高度显著性 (P <0 0 1) ;在鳞癌中 p5 3蛋白表达与组织分化程度相关 (P <0 0 5 ) ;p2 7和p5 3表达在鳞癌中呈负相关 (P <0 0 1)。 结论　p2 7蛋白表达的减少在口腔鳞癌的发生发展中起着重要作用 ,并与其预后因素密切相关。p5 3蛋白的表达在癌前病变向鳞癌转变过程中起重要作用。综合分析 p2 7、p5 3表达有助于口腔鳞癌的早期诊断和患者预后的估计。