Significance of Ki-67 and p53 immunoexpression in the differential diagnosis of oral necrotizing sialometaplasia and squamous cell carcinoma

Necrotizing sialometaplasia (NS) is a benign condition that usually involves the hard palate and can be mistaken for invasive squamous cell carcinoma (SCC). In this study, we have demonstrated that p53 and Ki-67 staining may assist in the differential diagnosis of NS from SCC. Thirteen cases of NS and 20 cases of oral cavity SCC were randomly selected from our surgical pathology archive from 1992 to 2009. Each case was additionally stained with Ki-67, p53, BCL-2, p16, and epidermal growth factor receptor (EGFR) antibodies. All 13 cases of NS were negatively stained for BCL-2, EGFR, and Ki-67. Three cases (23%) showed weak and focal positive nuclear staining for p53. Two cases (15%) showed positive staining for p16. In 16 well-differentiated SCC cases, p53 was positive in 12 cases (75%); BCL-2, p16, EGFR were positive in 3 cases (18%); and Ki-67 was positive in all cases (100%). In 4 moderately differentiated SCC cases, p53 expression was positive in all cases. Two tumors (50%) had a positive expression of BCL-2. Three cases (75%) had a positive p16 staining, and 1 (25%) had a positive EGFR staining. All cases were positive with high nuclear staining greater than 35% of cells for Ki-67. Ki-67 and p53 showed more intense staining and increased in moderately differentiated SCC comparing with well-differentiated SCC and NS. BCL-2, EGFR, and p16 had the same pattern of staining with the same extent in NS and SCCs. The diagnosis of NS may be difficult and may be supplemented via immunohistochemistry by demonstrating focal or absent p53, low to absent Ki-67 (<10% of cells). Although Ki-67 and p53 staining are generally more intense and are increased in malignancy, these findings may be helpful adjuncts in the differential diagnosis of NS from SCC in appropriate clinical setting.     

P53, p16 and Ki67 immunoexpression in oral squamous carcinomas

In this study, we have analyzed clinically, histopathologically and immunohistochemically a total of 34 cases of oral squamous carcinoma in 11 of the cases being identified adjacent epithelial dysplastic lesions. Carcinomas were diagnosed in patients aged 40-60 years, males, with chronic exposure to tobacco and/or alcohol, being located especially on the lips. Well-differentiated carcinomas have been predominant (52.9%) in stage I/II tumoral (88.3%). Immunoexpression analysis of p53, p16 and Ki67 did not reveal statistically significant differences between the expression of markers and clinical or histopathological parameters, except Ki67 whose increased expression was associated to the decrease of the degree of tumoral differentiation and with high degree dysplasia. The positivity index and the intensity of reaction were increased at the level of dysplasic epithelium for p16 and at the level of tumoral invasion front for the p53 and Ki67. The study highlights the value of the immunostain for p16 in identifying dysplasic lesions and predictive importance of p53 and Ki67 markers in identifying the aggressive forms of oral carcinomas.     

Expression of p53 in leukoplakia and squamous cell carcinoma of the oral mucosa: correlation with expression of Ki67

Aim—To study p53 expression in relation to proliferative status in normal and nondysplastic, dysplastic and malignant lesions of the oral mucosa.     

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。     

Accumulation of p53 in esophageal squamous cell carcinoma

D-mannoheptulose is a specific inhibitor of D-glucose phosphorylation by hexokinase isoenzymes. In the present study, the phosphorylation of this heptose was investigated by either a spectrophotometric or radioisotopic procedure. Using yeast hexokinase, the phosphorylation of 25 mM D-mannoheptulose only represented 0.02% of that of 5 mM D-glucose. Such a percentage was increased to 3.93% in the case of bovine heart hexokinase. In the latter case, the Km for D-mannoheptulose was close to 0.2 mM and both D-glucose (0.1-1.0 mM) and D-glucose 6-phosphate (also 0.1-1.0 mM) inhibited the phosphorylation of the heptose (0.03-0.60 mM). Human B-cell glucokinase also catalyzed the phosphorylation of D-mannoheptulose (0.1 mM), which was now increased in a bell-shaped manner by D-glucose (1.0-20 mM). Likewise, rat parotid gland, liver and pancreatic islet homogenates catalyzed the phosphorylation of D-[3H]mannoheptulose. The results obtained in these three tissues differed from one another by their absolute values (per mg wet wt.), relative values (by reference to the phosphorylation rate of 10 mM D-glucose), and sensitivity to inhibition by D-glucose (10 mM).     

p53 expression above the basal cell layer in oral mucosa is an early event of malignant transformation and has predictive value for developing oral squamous cell carcinoma

Epithelial dysplasia is usually used to establish the prognosis of oral premalignant lesions. Its assessment, however, is subjective and does not always correctly predict the outcome of the lesions in terms of malignant transformation. Early molecular alteration(s) that dictate the development of cancer should be identified and used to evaluate oral premalignant lesions. In this context, alterations in the expression of p53 were investigated. Thirty-five oral premalignant lesions and 11 carcinomas that developed from them in a period of 16 years were investigated for p53 expression by immunohistochemistry. Normal oral mucosa from healthy individuals and oral benign lesions were used as controls. In benign lesions and normal mucosa, p53 staining, when present, was confined to the basal cell layer. Seven out of 35 (20 per cent) premalignant lesions showed p53 expression clearly above the basal cell layer and six of these (86 per cent) developed carcinomas. Suprabasal p53 expression was found in three lesions with no or mild dysplasia that developed carcinomas. All carcinomas derived from premalignant lesions with p53 suprabasal expression showed p53 expression in neoplastic cells. The combined use of histological parameters (presence of moderate or severe dysplasia) with p53 expression patterns (p53 staining above the basal cell layer) showed the highest sensitivity for the detection of lesions that progressed to carcinoma (91 per cent). When used individually, the p53 expression pattern showed higher specificity than assessment of dysplasia (96 per cent vs. 54 per cent) and higher positive predictive value (86 per cent vs. 44 per cent) for correct prediction of the malignant transformation of the lesions. The results suggest that clear expression of p53 above the basal cell layer is an early event in oral carcinogenesis and an indicator of a developing carcinoma, even preceding morphological tissue alterations. However, since immunohistochemistry cannot always detect changes in p53 expression in lesions preceding carcinoma, p53 immunohistochemical analysis is strongly recommended in conjunction with histological parameters, to increase the sensitivity of detection of cases that will progress to carcinoma. © 1998 John Wiley & Sons, Ltd.     

p53 overexpression in oral mucosa in relation to smoking

The tumour-suppressor protein p53 is mutated in many head and neck squamous cell carcinomas (HNSCCs). In this immunohistochemical study, similar numbers of p53-overexpressing cells were uniformly distributed throughout normal oral epithelium, irrespective of different smoking habits or the presence of an adjacent HNSCC. In a previous study, an increased number of proliferating cells were observed in normal oral mucosa from (ex)-smoking individuals and the present observations indicate that overexpression of p53 does not play a role in this increase. In contrast, focally overexpressed p53 occurred more frequently (p < 0·05) in the tumour-adjacent normal mucosa (TAM) from smoking HNSCC patients (50 per cent) than in that from non-smoking HNSCC patients (20 per cent). This increase in focal p53 overexpression might represent an early alteration in the development of HNSCC, but it could not be detected in mucosa from healthy smokers. This indicates that besides the abuse of tobacco, other environmental and/or genetic factors must contribute to the presence of p53-positive clusters in TAM. Abuse of alcohol, an additional factor in these HNSCC patients, together with the abuse of tobacco, might play a role in the development of the p53-positive clusters. Copyright © 1999 John Wiley & Sons, Ltd.     

p53 Overexpression in laryngeal squamous cell carcinoma and dysplasia

Aim—To investigate the expression of p53 protein in invasive squamous cell carcinoma (SCC) of the larynx and dysplasia in relation to histological grade and tobacco smoking.     

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.     

食管鳞状细胞癌p53基因突变与p53蛋白过度表达的关系

p53基因是各种人类肿瘤包括食管癌中最常见有突变的基因之一。我们应用激光显微切割,聚合酶链反应（PCR）-杂合性缺失（LOH）,PCR-单链构象多态性分析（SSCP）,p53测序及免疫组织化学方法,检测了食管癌高发区中国山西省的56例患者食管鳞状细胞癌（ESCC）中p53基因缺失、突变及p53蛋白表达情况,旨在更好理解p53基因突变等变化在食管癌发生发展过程中的作用。     

p53 alterations in human squamous cell carcinomas and carcinoma cell lines.

p53 alterations were studied in a group of 22 primary squamous cell carcinomas (SCC) of the head and neck and in 10 cell lines derived from SCC. Positive immunohistochemical detection of p53 was accomplished in 10 of 22 primary tumors and in 7 of 10 SCC cell lines. Loss of heterozygosity of chromosome 17p, were the p53 gene is localized, was seen in five of seven SCC lines studied. DNA sequencing of the p53 gene of these five cell lines that had lost one allele showed p53 mutations in the remaining allele. In addition, from six primary SCC that exhibited loss of heterozygosity of chromosome 17p, three showed missense mutations of the p53 gene. The mutations of primary tumors and SCC cell lines were scattered in the midregion of the gene, affecting codons 151, 155, 174, 194, 220, 248, and 273. Five of these mutations modified guanine residues, a phenomenon that has been associated with the effect of carcinogens contained in tobacco smoke. Collectively these data show that approximately 50% of primary tumors and cell lines derived from SCC of the head and neck showed abnormalities of the p53 gene. In addition, it is of interest to note that the most invasive cell lines, as determined in an in vivo assay using xenotransplantation of tumor cells into denuded rat tracheal grafts, exhibited the most intense staining. Similarly, of five very advanced primary tumors, four showed intense p53 immunostain. These observations support the evidence that alterations in this tumor suppressor gene could be related to late events in tumor progression.     

口腔鳞癌中人端粒酶反转录酶、p53和MIB-1的表达及其临床意义

目的 探讨人端粒酶反转录酶(hTERT)、p53和MIB-1蛋白在口腔鳞癌组织中的表达及临床意义.方法 采用Envision免疫组织化学染色方法(IHC)检测20例口腔黏膜普通型增生、35例非典型增生(轻度10例、中度10例和重度15例)以及50例不同分化程度(高分化15例,中分化20例,低分化15例)的口腔鳞状细胞癌(OSCC)中hTERT、p53和MIB-1的表达.结果 hTERT、p53和MIB-1在口腔黏膜普通型增生、非典型增生及不同分化程度的OSCC均有不同程度表达.OSCC表达阳性率[中分化鳞癌hTERT:60％( 12/20)]高于普通型增生[hTERT:10％(2/20)]及非典型增生[中度非典型增生hTERT:30％(3/10)].分化程度低的OSCC表达阳性率[hTERT:66.7％(10/15)]显著高于分化程度高者[hTERT:46.7％(7/15)].结论 hTERT、p53和MIB-1在口腔OSCC发生、发展过程中起重要作用,并与OSCC的分化程度密切有关,可能是OSCC的较好预后指标.     

The clinicopathologic significance of p53 and p21 expression in the surgical management of lingual squamous cell carcinoma

The aim of the present study was to evaluate the clinicopathologic significance of p53 and p21 expression in lingual squamous cell carcinomas. Immunohistochemical staining was performed with p53 and p21 monoclonal antibodies on surgical specimens from 87 patients who underwent primary surgical treatment for lingual carcinoma between 1976 and 1996. We found positive expression of p53 in 45 (52%) of 87 cases and of p21 in 49 (56%) of 87 cases. There was no correlation of p53 and p21 expression with cancer stage, T stage, nodal metastasis, and tumor grade. Univariate analysis revealed that p21 expression, tumor stage, T stage, and nodal stage were significant prognostic factors for survival. However, only p21 expression and tumor stage were significant independent prognostic factors for survival in a multivariate Cox regression analysis. Overexpression of p21 but not p53 has prognostic value for survival in the surgical treatment of lingual carcinomas. The combination of stage with p21 expression is recommended for evaluation of prognosis and for management planning.     

Prognostic significance of p53 and p63 immunolocalisation in primary and matched lymph node metastasis in oral squamous cell carcinoma

This study evaluates the prognostic significance of p53 and p63 immunolocalisation in oral squamous cell carcinoma samples from 45 matched primary tumors (PT) and lymph node metastases (LNM). Data regarding patient age, gender, primary site, histological differentiation, metastasis, disease-free survival (DFS) and overall survival (OS) were available. p53 and p63 immunolabeling was detected in 17 (37.8%) and 23 (51.1%) of the PT, respectively. For LNM, there was p53 and p63 labeling in 23 (51.1%) and 26 (57.8%) cases, respectively. Most cases showed similar labeling in PT and the corresponding LNM (73.3% for p53 and 53.3% for p63, respectively). No statistically significant associations were found between p53 and p63 immunolabeling and histological differentiation; p63 positive tumors showed higher DFS (p=0.006) and OS (p=0.049); and p53-negative tumors had a higher DFS interval (p=0.009). Our findings suggest that initially p53-negative tumors and initially p63-positive tumors that retain this labeling pattern may follow less aggressive biological courses and present better prognoses.     

A scanning electron microscopic study of the dysplastic epithelia adjacent to oral squamous cell carcinoma

By light microscopy, the dysplastic oral epithelia due to the neoplastic processes are similar to epithelial changes due to the inflammatory processes. Scanning electron microscopy may elucidate the different surface changes between the two. The aim of this study was to examine the surface appearances of the dysplastic oral epithelia adjacent to oral squamous cell carcinoma to see if there are any surface changes. A total of 2 specimens, one specimen from each patient with oral squamous cell carcinoma, were used for this study. Each specimen was divided in two. One half was prepared for light microscopy and the other half was prepared for scanning electron microscopy. Light microscopically, the epithelia showed mild dysplasia. By scanning electron microscopy, the keratinized cells showed irregular microridges surrounding pits, which were variable and irregular in size and shape, and the nonkeratinized cells showed parallel microridges with irregularly widened intervals between each microridge. Irregular, broad, and partly swollen microridges and irregular short, stubby surface projections were also seen. The oral epithelia adjacent to oral squamous cell carcinoma showed mild dysplasia light microscopically but appeared abnormal by scanning electron microscopy. The abnormal epithelial cells showed pleomorphism, irregular and disoriented microridges, and abnormal surface microstructures.     

p53 gene mutations in sequential oral epithelial dysplasias and squamous cell carcinomas

Previous studies of oral cancer have suggested that alterations of the p53 tumour suppressor gene occur early in the precancerous stage of development. However, these observations have been based on cross-sectional assessment of abnormal p53 protein staining by immunohistochemistry and may not necessarily reflect gene changes. The purpose of this longitudinal study was to examine the changes in the p53 gene in progressive, sequential epithelial dysplasias and carcinomas from the oral cavity. The study analysed 24 formalin-fixed, paraffin-embedded tissue biopsies from ten patients with two or more temporally distinct lesions from the same site in the oral cavity with the diagnosis of hyperkeratosis, epithelial dysplasia, carcinoma in situ or squamous cell carcinoma. Exons 5-8 of the p53 gene were amplified from genomic DNA using intronic primers and directly sequenced using fluorescent-labelled primers. Standard immunohistochemistry with the DO7 monoclonal antibody was used to detect mutant and wild-type p53 protein. Mutations of the p53 gene were identified in 9 of 24 samples. Eight were missense mutations and one occurred at a splice site. In six patients, mutations of the p53 gene occurred late after the transformation of epithelial dysplasia to carcinoma. In two patients with progressive dysplasia, but who had yet to develop invasive carcinoma, p53 missense mutations occurred at the carcinoma in situ stage in one case and in a moderate dysplasia in the other. There was an inconsistent relationship between gene mutations and the level of p53 protein staining by immunohistochemistry. It is concluded that during oral carcinogenesis, p53 gene mutations seem to occur relatively late and are associated with transformation to the invasive phenotype.     

Changes in immunoexpression of E-cadherin and β-catenin in oral squamous cell carcinoma with and without nodal metastasis

The aim of this study is to analyze the immunohistochemical expression of E-cadherin and β-catenin in oral squamous cell carcinoma to better understand the biological behavior of this lesion. The sample consisted of 15 cases of the tongue and 15 of the lower lip. The pattern and intensity of the labeling and the analysis of the percentage of tumor cells immunopositive in membrane for E-cadherin and β-catenin were related to the anatomic location of the lesion, the presence or absence of nodal metastasis, and the histological gradation of malignancy in the tumor invasion front. The presence or absence of cytoplasmic and nuclear labeling was also recorded. The membrane expression for E-cadherin and β-catenin predominately displayed a heterogeneous pattern in the carcinomas studied. No significant difference was observed between the expression pattern and the quantity of cells immunopositive for E-cadherin and β-catenin and the anatomic location of the lesion or the presence or absence of nodal metastasis. However, a statistically significant difference was found between the reduced expressio\n of these proteins and the high malignancy score. The reduced immunoexpression of these proteins in the membrane may be related to the high degree of cell indifferentiation in cases of oral squamous cell carcinoma with high scores.     

Impact of the epithelial dysplasia grading and Ki67 proliferation index in the adjacent non-malignant mucosa on recurrence and survival in head and neck squamous cell carcinoma

This study aimed to evaluate the association between several different aspects of disease in head and neck squamous cell carcinoma (HNSCC): morphological grading, Ki67 proliferation index (PI), invasive front, adjacent non-malignant mucosa (ANMM), recurrence and overall survival of the patients. Sixty-four fully reviewed and followed-up patients with primary HNSCC were matched according to recurrence of the lesion and placed in one of two groups of 32 cases. Chi-square and Fisher's exact tests were used to analyze the clinicopathological parameters between both groups of patients. Association between Ki67 PI and clinicopathological parameters was also analyzed through chi-square and Fisher's exact tests with the binary logistic regression model used as a multivariate analysis. In addition, survival analysis was also performed. Our results showed that high-risk dysplasia in ANMM and high Ki67 PI in ANMM of HNSCC exhibited a higher risk of tumor recurrence. Survival analysis showed that T3/T4 tumor sizes and high Ki67 PI were significantly associated with an increase in the risk of death in multivariate analysis. Our results revealed that high-risk dysplasia and high Ki67 PI of the ANMM are parameters which are indicative of tumor recurrence. Furthermore, T3/T4 tumor sizes and high Ki67 PI in the invasive front appear to be important prognostic tools for HNSCC.     

PDCD5和Smac在口腔鳞癌中的表达及临床意义

目的研究凋亡相关新基因PDCD5与Smac蛋白在口腔正常黏膜、口腔鳞癌中表达的相关性及其意义。方法采用免疫组化方法检测68例口腔鳞癌组织和43例癌旁正常黏膜组织中PDCD5和Smac的表达,并分析两者的表达与临床病理的关系以及两者之间相互关系。结果正常口腔黏膜组PDCD5染色阳性率为80.2%(P0.05),口腔鳞癌组PDCD5阳性率为29%(P0.05),明显低于癌旁组织,并且表达与TNM分期、淋巴结转移相关性有统计学意义(P0.05)。Smac在正常口腔黏膜组染色阳性率为41.2%(P0.05),明显高于口腔鳞癌组织11.7%(P0.05),且与肿瘤的分化程度、TNM分期、淋巴结转移的相关性均有统计学意义(P0.05)。PDCD5和Smac蛋白呈明显正相关(r=0.892,P0.05)。结论PDCD5和Smac蛋白在口腔鳞癌中表达下调,提示PDCD5与Smac蛋白的改变可能与口腔鳞癌的发生、发展相关,这两项指标可作为辅助口腔黏膜癌变的基因标志物。     

The influence of p53 and associated factors on the outcome of patients with oral squamous cell carcinoma

 In several tumour entities the immunohistochemical detection of p53 has proved to be a predictive factor for the survival of the patients. In this study the effector waf1 and the regulator mdm2 responsible for the inactivation of p53 were also determined in 156 tissue samples of primary squamous cell carcinomas in the oral cavity and oropharynx, their lymph node metastases, and the epithelium outside the invasively growing tumour from 107 patients. In this latter epithelium there was a significant correlation between grade of dysplasia and staining for p53 (P<0.01). In the dysplastic epithelium a significant correlation between p53, waf1, and mdm2 was shown (P<0.05). Differences in the immunohistochemical staining between different blocks of the tumour tissue and also between primary tumours and their lymph node metastases were revealed in 11–44% of cases, but there was no correlation with other variables, such as formation of lymph node metastases. In contrast to the conventional tumour grading and staging, no influence of any of the variables determined on survival or recurrence-free survival could be detected. It seems that p53 and associated factors are important in the early stages of cancerogenesis but not in further tumour progression and metastatic spread. Received: 26 March 1998 / Accepted: 10 June 1998