p53 mutations and human papillomavirus infection in oral squamous cell carcinomas: correlation with overall survival.

PURPOSE: The study investigated the pattern of p53 gene mutations and human papillomavirus (HPV) infection concerning their relation to overall survival in patients with oral squamous cell carcinomas of the tongue and floor of the mouth. PATIENTS AND METHODS: The presence of HPV infection in 50 patients, and p53 gene mutations (42 patients from the same group) in the tumour specimens were analysed by polymerase chain reaction and single-stranded conformational polymorphism method. The follow-up period ranged from 12 to 48 (median 29) months. RESULTS: p53 mutations were identified in 11/42 tumours. HPV infection was detected in 32/50 cases, mostly HPV16 (10/32), HPV18 and HPV31 (6/32). A significantly higher incidence of HPV infection was found among smokers (p<0.05) and among patients with poor oral hygiene (p<0.01). The highest incidence of p53 mutations was detected in tumours of histological grade I and nuclear grade III. Patients with p53 mutation or with HPV infection had significantly shorter overall survival when compared with those that were without p53 mutations (p<0.01) or HPV infection (p<0.05). HPV-infected patients with p53 mutation had the worst prognosis when compared with patients with HPV infection only (p<0.01) or with patients negative for both HPV and p53 (p<0.01). CONCLUSION: The results stress once more the importance of HPV for the prognosis of survival of patients with squamous cell carcinoma of lower parts of the oral cavity. The presence of p53 mutations in HPV-infected tumours was associated with an even poorer prognosis for the patients.     

口腔鳞癌中HPV感染及其对p5 3改变影响的研究

目的：探讨高危型人乳头状瘤病毒（ＨＰＶ）在口腔鳞癌中的感染情况及其对Ｐ５３蛋白表达和ｐ５３突变的影响。方法：采用免疫组化和ＰＣＲ－ＳＳＣＰ方法，分别检测４０例来癌中高危型ＨＰＶＥ６蛋白表达、Ｐ５３蛋白表达和ｐ５３基因突变的情况。结果：９例ＨＰＶＥ６蛋白染色阳性，阳性率２２．５％（９／４０），与正常粘膜对照组有显著差异（Ｐ＝０．０２１）。ＨＰＶ阳性组中Ｐ５３蛋白表达率１１．１％（１／９），ＨＰＶ阴性     

人乳头状瘤病毒16/18型、p53、p16蛋白在口腔疣状癌中的表达

目的　研究人乳头状瘤病毒 16 / 18型、p5 3、p16蛋白在口腔疣状癌中的表达状况 ,探讨它们在口腔疣状癌发生发展中的生物学意义。方法　采用SP免疫组化和原位杂交方法分别检测 8例正常口腔粘膜、13例疣状癌、10例高分化鳞癌、10例低分化鳞癌组织中HPV16 / 18E6、p5 3、p16蛋白和HPV16 / 18DNA的表达。结果　 1.疣状癌HPV16 / 18E6蛋白和p5 3蛋白阳性表达率均为 6 9.2 % (9/ 13) ,p16蛋白表达缺失率为 2 3.1% (3/ 13) ,过度表达率为 6 9.2 % (9/ 13) ,平均染色强度与高分化鳞癌和低化分鳞癌组比均有显著性差异 (P <0 .0 5 )。 2 .免疫组化方法检测HPV16 / 18E6蛋白与原位杂交方法检测HPV16 / 18DNA结果有良好的一致性。 3.疣状癌HPV16 / 18E6蛋白与p5 3蛋白、p5 3蛋白与p16蛋白表达之间无相关性 (P <0 .0 5 ) ,而HPV16 / 18E6蛋白与p16蛋白表达之间呈正相关 (P<0 .0 5 )。结论　 1.进一步证实HPV16 / 18型感染是口腔疣状癌的重要致病因子。 2 .疣状癌的发生过程中可能存在p5 3基因突变。 3.p16基因变异在疣状癌的发生中起一定作用 ,用疣状癌中p16蛋白过度表达与HPV16 / 18型感染有关。 4 .HPV16 / 18、p5 3、p16蛋白在疣状癌与高分化鳞癌、低分化鳞癌组织中的表达存在明显差异 ,证实疣状癌是一种独立类型     

Human papillomavirus, p53 and cyclin D1 expression in oropharyngeal carcinoma

Forty-two specimens from oropharyngeal (tonsil and base of tongue) squamous cell carcinoma patients (SCC) were studied for presence of HPV 16 by in situ hybridization and by immunohistochemistry for p53 and Cyclin D1 protein overexpression. Thirty-one per cent of cases were HPV-16 positive, which correlates with the prevalence reported worldwide. 74% of cases showed p53 protein overexpression and 79% showed Cyclin D1 overexpression. There was no correlation between HPV status and either p53 or Cyclin D1 overexpression (P>0.05). These three variables also did not correlate with factors such as grade of the tumour, stage of the disease or lymph nodal metastasis at presentation.     

Alterations of tumor suppressor genes and the H-ras oncogene in oral squamous cell carcinoma

The frequencies of mutations in the adenomatous polyposis coli (APC). p53, and p16 (MTS1: multiple tumor suppressor 1/CDK4I: cyclin-dependent kinase 4 inhibitor) tumor suppressor genes were investigated in 23 oral squamous cell carcinomas (SCCs). Loss of heterozygosity (LOH) at the retinoblastoma (Rb) gene locus and on chromosomes 3p (VHL; von Hippel-Lindau disease tumor suppressor gene locus). 5q (APC) and 9p (p16). and H- ras oncogene mutations were also studied in the same samples. Techniques employed were polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP), DNA sequencing and PCR-microsatellite analyses. Mutations of the p53 gene were detected in 26% (6/23) of the tumor specimens. APC and p!6 were not mutated in any of the 23 oral SCCs studied. LOH was detected in 17% (2/12 informative cases) at the Rb, in 33% (4/12) on 3p, in 17% (4/23) on 5q and in 30% (3/10) on 9p. Mutations of the H- ras gene were detected in 9% (2/23). The only correlation between these genetic alterations and clinicopathologic characteristics was that mutations of the p53 gene were detected more frequently in oral SCCs with lymph node metastasis than in those without it ( P <0.05). These results demonstrate that mutations of the p53 gene and LOH on 3p and 9p frequently occur in oral SCC and play important roles in the development and/or progression of this common malignancy.     

Comparative study of HPV prevalence in Japanese and North-east Chinese oral carcinoma

BACKGROUND: Human papillomavirus (HPV) plays a role in the development of oral carcinoma. However, the reported prevalence of HPV in oral carcinoma has varied widely. METHODS: The prevalence of HPV 16, 18 and 33 was investigated in Japanese and North-east Chinese oral squamous cell carcinomas (OSCCs) with polymerase chain reaction (PCR). The expression of p53 protein was examined immunohistochemically. RESULTS: HPV 16 and 18 were detected in 7 (23.3%) and 10 (33.3%) of 30 Japanese and 11 (36.7%) and 5 (16.7%) of 30 Chinese samples, respectively. HPV 16 and 18 coinfection was detected in 3/30 Japanese and 2/30 Chinese samples. HPV 33 was not detected. There was no significant correlation between HPV 16 and 18 and the sites, gender, age and histological grade. The prevalence of both HPV 16 and 18 was similar and higher in the Japanese and North-east Chinese samples (46.7% each). HPV 16 or/and 18 infection or/and p53 overexpression were in 22 (73.3%) of 30 Japanese samples and 24 (80.0%) of 30 North-east Chinese samples, respectively. CONCLUSIONS: HPV 16/18 infection or/and p53 overexpression may play an important role in developing some OSCCs. and the presence of HPV sequences and mutant p53 are not necessarily mutually exclusive.     

Cancer genes alterations and HPV infection in oral squamous cell carcinoma

The aim of this study was to gain a better understanding of cancer genes contributing to oral squamous cell (OSCC) development and progression and correlate genetic changes to clinical parameters. Human papilloma virus (HPV) 16 detection is also included in the study. 60 samples of OSCC were analysed for c-erbB2 and c-myc amplification by dPCR, H-ras and p53 point mutations by PCR/SSCP. HPV was detected via amplification of its E1 and E6 genes. c-erbB2 was altered in 45%, c-myc in 35%, H-ras in 22% and p53 in 60% of samples. HPV was detected in 10% of cases. The frequency of p53 gene mutations showed a statistically significant association with tumour stage. Patients with c-erbB2 and H-ras alterations had lower survival than patients without these alterations. The number of detected genetic changes was remarkable but statistical association with tumour natural history was poor, indicating high clonal heterogeneity and multiple pathways of carcinogenesis.     

Association of HPV infections with second primary tumors in early-staged oral cavity cancer

Oral Diseases (2012) 18 , 809–815 Objective: The infection of human papilloma virus (HPV) has been reported in head and neck cancer; however, the clinical significance of HPV infection on the pathogenesis of oral cavity squamous cell carcinoma (OSCC) is still uncertain. Materials and Methods: The study recruited 103 patients with pathological early‐stage OSCC between March 1997 and December 2003 from Chang Gung Memorial Hospital, Taiwan. Tumor specimens were HPV‐genotyped by the EasychipVR HPV Blot method. Clinical association study was performed by using chi‐square, Kaplan–Meier, and logrank tests. Results: Thirty‐one patients (30.1%) were positive for HPV infection. The most frequent HPV types were types 16 (16 patients, 51.6%) and 18 (seven patients, 22.6%). HPV infection was not associated with tumor aggressiveness (pathological tumor stage or differentiation status), risk exposure (alcohol, cigarette, or areca quid chewing habit), or the treatment outcome (disease‐free survival or overall survival). However, infection with HPV‐18 was associated with the occurrence of a second primary cancers (P = 0.033), indicating the infection of HPV in OSCC enhances the susceptibility of developing secondary malignancy. Conclusions: There are 30% of the patients with OSCC infected with HPV, with most high‐risk types. HPV‐18 infection may enhance the susceptibility of second primary tumors. Large scale of validation study will be needed to confirm this result.     

口腔鳞癌中HPV16、18型感染和p53蛋白表达的检测研究

目的探讨人类乳头状瘤病毒(human papillomavirus, HPV)感染、p53蛋白表达在口腔鳞状细胞癌发生、发展中的作用与相互关系.方法采用聚合酶链反应(PCR)检测HPV16、18型DNA;采用免疫组织化学LSAB法检测p53蛋白产物在细胞核中的表达.结果口腔鳞癌组中HPV16、18 DNA总阳性率为48.89%(22/45),p53蛋白表达阳性率为62.22%(28/45).HPV16、18型感染组及p53蛋白过度表达组的平均生存期、生存率均低于无HPV感染组(P>0.05)及无p53过度表达组(P<0.05).结论 HPV16、18型感染、p53基因突变与口腔鳞癌的发生密切相关.口腔鳞癌患者的预后在一定程度上与HPV感染、p53表达状况有关.     

Mutated and wild-type p53 expression and HPV integration in proliferative verrucous leukoplakia and oral squamous cell carcinoma

The frequencies of overexpression and mutation in the p53 tumor suppressor gene were examined in proliferative verrucous leukoplakia and oral squamous cell carcinoma with immunohistochemistry and single-strand conformation polymorphism analysis of DNA fragments amplified by polymerase chain reaction. Ten samples each of normal oral mucosa, proliferative verrucous leukoplakia, and squamous cell carcinoma were immunostained with antibodies against p53 protein; 8 of 10 cases of proliferative verrucous leukoplakia cases and 7 of 10 cases of oral squamous cell carcinoma were positive for p53 protein. Minimal staining was observed in normal oral tissues. The quantified labeling indexes demonstrated a range that corresponded to lesion progression. Single-strand conformation polymorphism analysis revealed p53 gene mutations within exons 5 to 8 in 40% (4 of 10) of the squamous cell carcinoma samples. Two of the 4 mutated squamous cell carcinoma samples lacked p53 expression. No p53 mutations were detected in proliferative verrucous leukoplakia tissues. Human papillomavirus 16 was identified in 2 of 7 p53 positive oral squamous cell carcinoma samples. Human papillomavirus 16 and 18 were identified in two of eight p53 positive proliferative verrucous leukoplakia samples. One p53 negative squamous cell carcinoma sample was positive for human papillomavirus 16 and had a mutation in exon 6 of the p53 gene. Human papillomavirus infection along with p53 expression plays a yet to be defined role in the pathogenesis of a limited number of cases of proliferative verrucous leukoplakia and squamous cell carcinoma. p53 Immunohistochemistry, p53 gene mutations, and human papillomavirus infection prevalence do not provide a means to differentiate between leukoplakia and carcinoma and do not provide a predictive test for progression of leukoplakia to carcinoma.     

The correlation between alteration of p16 gene and clinical status in oral squamous cell carcinoma

The purpose of the study was to evaluate the presence of alteration of the tumor suppressor gene p16 and to correlate these changes with the clinical status of the patients in oral squamous cell carcinoma. Forty-eight oral squamous cell carcinomas were included in the analyses. Deletion analysis was performed by the polymerase chain reaction (PCR). Mutation analysis was restricted to exon 1 and exon 2 of the p16 gene, previously shown to have a high incidence of mutations. The sequences containing exon 1 and exon 2 were amplified by PCR and screened with a single-strand conformation polymorphism (SSCP) technique. Samples showing band shifts in SSCP were sequenced by PCR direct sequencing. Western blots were used to detect the protein expression of the p16 gene, and the results were evaluated with regard to their biological relevance in correlation with clinicopathological factors. Seven (14.6%) deletions were found; 5 (10.4%) mutations were discovered and located in different codons; 26 (54%) specimens had no p16 protein expression; in 11 specimens with p16 deletion or mutation, p16 protein could not be detected. One mutation was non-sense. The p16 gene alterations showed no relationship with location and clinical stage of cancer; however, a close relationship between p16 alterations and cancer metastasis to neck lymph node was found. The alteration rate gradually elevated from well to poorly differentiated grades. We perceive two results. First, the alterations of the p16 gene are common in oral squamous cell carcinoma. Second, the alterations of the p16 gene may attribute to the metastatic behavior or histological grade of cancer cells.     

Analysis of HPV 16 and 18 by in situ hybridization in oral papilloma of HIV+ patients

Human immunodeficiency virus (HIV) infection facilitates the development of other infections and lesions including oral papilloma, which has been associated with human papillomavirus (HPV). In analyzing the presence of HPV 16 and 18 by in situ hybridization in oral papillomas from five HIV+ male dental patients, HPV 16 and 18 were observed in 9 of 16 (52.2%) histopathologic specimens. All positive lesions occurred in heterosexual males admitting to oral sexual contact with a female partner (Pearson's correlation; p = 0.0088). These results suggest that oral sexual behavior may be a contributing factor in the presence of HPV 16 and 18 in oral papilloma.     

Incidence of human papillomavirus 16 and 18 infection and p53 mutation in patients with oral squamous cell carcinoma in Japan

The purpose of this study was to investigate the prevalence of human papillomaviruses (HPVs) 16 and 18 infection, and p53 mutation in oral squamous cell carcinomas (SCCs) in Japanese patients. Our results showed a higher incidence of HPV16 and 18 infections than previous studies because we combined the findings of a consensus polymerase chain reaction (PCR), restriction fragment length polymorphism by using the restriction enzyme digestion of the PCR products and Southern blot hybridization. Each HPV16 and 18 E6/E7 DNA was detected in 9 (20%) and 25 (54%) of 46 samples. The p53 mutation in the exons from 5 to 8 were detected in 20 out of 46 samples (43%) by a PCR-single strand conformation polymorphism analysis. There was a significant relationship between HPV16 and the p53 mutation (P =0.02) suggesting that HPV16 infection has a mutagenic effect in oral SCC. However, neither HPV infection nor p53 mutation influenced survival.     

Loss of the adenomatous polyposis coli gene and human papillomavirus infection in oral carcinogenesis

Recent evidence suggests that loss of heterozygosity (LOH) of the adenomatous polyposis coli (APC) gene plays a role in colorectal tumorigenesis and other cancers. However, little is known as to whether the APC gene contributes to the pathogenesis of oral squamous cell carcinoma. To assess involvement of both the APC gene and the human papillomavirus (HPV) in the development of oral pre-malignant and malignant lesions, we analysed DNA from 14 paired oral normal and pre-malignant or malignant paraffin-embedded biopsy specimens, and DNA from cultured normal and HPV 16-immortalised oral epithelial cells for the presence of LOH of APC and for HPV infection, using PCR based techniques. LOH of APC occurred in 80% of cases of oral epithelial dysplasia, 67% of carcinoma in situ, 50% of invasive squamous cell carcinoma cases, and in the HPV 16-immortalised oral epithelial cells. HPV was detected in half of the biopsy specimens, with HPV 16 as the dominant type. More than half of the carcinoma cases were found to contain both LOH of APC and HPV infection. These results suggest that LOH of APC is an early event during oral tumorigenesis. Our findings also suggest a strong correlation between HPV infection, particularly HPV 16, and LOH of the APC gene in oral squamous cell carcinomas.     

Immunohistochemical analysis of cell cycle-associated proteins p16, pRb, p53, p27 and Ki-67 in oral cancer and precancer with special reference to verrucous carcinomas

Alterations in cell proliferative activity are a common phenomenon in oral carcinogenesis. In this study, the expression of the cell cycle-associated proteins p16, pRb, p53, p27 and Ki-67 were examined by immunohistochemistry in precancerous and cancerous oral lesions, including verrucous carcinomas (VCs). Generally, expression of pRb, p53 and Ki-67 increased according to the cell proliferative activity or tumor progression, but p27 expression showed an inverse relationship. Comparing squamous cell carcinomas (SCCs) with VCs, there was a great difference in expression levels of p27, Ki-67 and p53, which seemed to reflect the different cell proliferative activities of these two tumors. Expression of p16 was low in both dysplasia and SCCs, whereas p16 expression was high in VCs. The high immunohistochemical expression for both p16 and pRb in VC is quite different compared with SCC, which may indicate a possible relationship between VC and human papillomavirus (HPV) infection.     

Overexpression of p53 and bcl-2 proteins and the presence of HPV infection are independent events in head and neck cancer

The expression of p53 and bcl-2 proteins by immunohistochemistry and the identification of human papillomavirus (HPV) infection by a non-isotopic polymerase chain reaction (PCR)based method were investigated in 30 patients with head and neck cancer. Ten cases were HPV-positive (33%), mostly as double or multiple infections by high- or intermediate-risk types. Twenty-one patients were p53-positive (70%), 9/10 with HPV-positive tumours and 12/20 with HPV-negative tumours; this difference was not statistically significant. Only four cases were bcl-2-positive, irrespective of the presence of either HPV or p53. No correlation was found between these biological factors and tumour stage, differentiation grade, and alcohol or tobacco use. Our findings indicate that p53 is involved in the majority of cases, bcl-2 is rare, and high-risk HPV could play a key role, especially in tumours of tongue and tonsil. In conclusion p53 and bcl-2 protein expression and the presence of HPV infection are independent events in these malignancies.     

口腔鳞癌HPV16、18感染与多基因表达的相关性研究

目的:检测口腔鳞状细胞癌(oral squamous cell carcinoma,OSCC)p53、Ki-67、Rb、p16和cyclin D1蛋白表达与高危型人类乳头状瘤病毒(human papilloma virus,HPV)感染的相互关系.方法:对73例OSCC组织标本,应用免疫组织化学ABC法检测病变组织中p...     

P53 and cyclin D1 staining patterns of malignant and premalignant oral lesions in age-dependent populations.

OBJECTIVE: Recent epidemiologic studies have identified a trend of increasing cancer incidence in younger patients. The purpose of this study was to determine whether this might be reflected by different molecular mechanisms for tumor development. STUDY DESIGN: Dysplastic and malignant oral lesions from age-distinct patient populations were immunohistochemically analyzed for expression of p53 and cyclin D1. Chi-square analysis was used to determine statistical significance. RESULTS: Eighty-two percent of "older" and 75% of "younger" carcinomas stained positively with p53; 63% of carcinomas in the older population and 55% of carcinomas in the younger population showed cyclin D1 positivity. Dysplasias showed similar cyclin D1 staining in both groups. Interestingly, 100% of "younger" dysplasias stained positively for p53, whereas 35.3% of "older" dysplastic lesions showed immunoreactivity. Staining of carcinomas was not statistically significant, whereas p53 staining of dysplasias proved highly significant (P < .025). CONCLUSIONS: p53 immunoreactivity is detectable at an earlier stage of carcinogenesis in younger patients than in the traditional risk population for oral cancer.     

p53 polymorphism, human papillomavirus infection in the oral cavity, and oral cancer

OBJECTIVES: Human papillomavirus (HPV) infection has emerged as a risk factor in oral carcinogenesis. An arginine-coding polymorphism of the tumor suppressor protein p53 at codon 72 is more readily degraded by the HPV oncoprotein E6. Our objective was to evaluate the association between p53 polymorphism at codon 72 and HPV infection in the oral cavity, as well as its association with oral cancer.Study Design: Oral squamous cells from 202 patients with oral cancer and 333 age-sex frequency matched controls were evaluated by polymerase chain reaction for the presence and type of HPV and for alleles of codon 72 in p53. Fisher exact test and chi(2) tests were used to evaluate the data. RESULTS: The p53 codon 72 polymorphism is not associated with HPV infection, whether comparing HPV-negative controls with HPV-positive controls or comparing HPV-negative cases with HPV-positive cases. Additionally, we found no association with the codon 72 polymorphism and oral cancer, whether comparing HPV-negative controls with HPV-negative cases or comparing HPV-positive controls with HPV-positive cases. CONCLUSIONS: There is no association between p53 codon 72 polymorphism and HPV infection or between the p53 polymorphism and the risk of oral cancer.