HPV16型E5基因对人永生化口腔上皮细胞E6、E7基因表达的影响

目的:研究HPV16型E5基因对人永生化口腔上皮细胞(human immortalized oral epithelial cell,HIOEC)E6、E7基因的影响。方法:HIOEC转染pLEGFP-E5基因反转录病毒载体,同时人为突变E5基因并转染HIOEC,通过PCR检测E5及各突变体在HIOEC中的表达。实时定量PCR检测E6、E7基因mRNA水平表达量的变化以及转染后HIOEC的细胞增殖能力,采用SPSS 13.0软件包对数据进行统计学处理。结果:构建了E5缺失突变体反转录病毒载体并成功转染人永生化口腔上皮细胞。转染后人永生化口腔上皮细胞的增殖行为实验表明,HPV16E5基因可促进人永生化口腔上皮细胞增殖(P<0.05),并对E6、E7基因mRNA表达具有正调控作用,但其缺失突变基因反转录病毒载体对人永生化口腔上皮细胞增殖及E6、E7表达无显著影响。结论:HPV16型E5基因可在一定程度上促进人永生化口腔上皮细胞增殖,并对E6、E7基因mRNA表达量有一定的间接上调作用。     

人乳头瘤病毒与口腔肿瘤及其16E5基因

人乳头瘤病毒（HPV）是一种小型无包膜的双链环状DNA肿瘤病毒,根据其伴随上皮损伤的恶性程度分为低危型和高危型,高危型HPV持续感染是口腔鳞状细胞癌（OSCC）形成的最重要因素,75%的OSCC中可检测到高危型HPV16。HPV16全长基因组分为早期区（E区）、晚期区及非编码调节区,其中E区包括8个开放阅读框,即E1~E8。HPV16E5基因引起细胞融合并形成双核细胞,是恶性肿瘤发生的征兆。表皮生长因子受体（EGFR）是HPV16E5蛋白作用机制中的关键部分,控制细胞的生长和增殖进程。肿瘤细胞中存在着EGFR过表达现象,一些抗癌药物抑制EGFR表达可起到治疗肿瘤的作用。环加氧酶（COX）2是一种可在人体中促进细胞增殖、抑制程序性细胞死亡和促进血管形成的酶,HPV16E5蛋白与EGFR协同诱导COX2表达,共同参与肿瘤的恶性转化进程。本文就HPV与口腔肿瘤、HPV16E5基因的功能等研究进展作一综述。     

HPV and other risk factors of oral cavity/oropharyngeal cancer in the Czech Republic

OBJECTIVE: An association between high-risk human papillomavirus (HR HPV) infection and a risk of development of a subgroup of head and neck cancers has been proposed recently. The main risk factors of oral and oropharyngal cancer observed in our population are smoking and alcohol consumption. The incidence of oral/oropharyngeal tumours in the Czech Republic is relatively high and there are no data available about the prevalence of HPV DNA presence in these tumours. MATERIALS AND METHODS: Eighty patients with a primary oropharyngeal cancer were enrolled. The presence of HPV DNA has been evaluated by polymerase chain reaction in 68 cases from which the tumour tissue and demographical and clinical data were available. The typing of HPV was performed by nucleotide DNA sequencing. RESULTS: The HPV DNA was detected in 51.5% of samples tested. Among the HPV DNA positive tumours, 80% contained HPV16. In the analysed group there were 54 men and 14 women. The prevalence of HPV DNA was lower in oral (25%) than in oropharyngeal (57%) tumours, and higher in never smokers (100%) and never drinkers (68.8%). HPV DNA presence was not related to gender, age, number of lifetime sexual partners or practice of oral-genital sex, size of tumour or presence of regional metastases. CONCLUSIONS: The difference in the prevalence of HPV DNA positive tumours between cases of oral cavity and oropharyngeal carcinoma exposed and not exposed to tobacco or alcohol support the theory that HPV DNA positive tumours form an aetiologically distinct subgroup of head and neck tumours.     

Association of marijuana use with oral HPV infection and periodontitis among Hispanic adults: Implications for oral cancer prevention

1 Background

Despite limited data, research suggests that marijuana use is associated with oral HPV infection and periodontitis, two potential oropharyngeal cancer risk factors. We assessed these associations in a Hispanic adult population in Puerto Rico.

2 Methods

A cross‐sectional study of 735 adults assessed marijuana use, determined through an audio computer‐assisted self‐interview, and periodontitis and self‐collection of oral HPV samples following the National Health and Nutrition Examination Survey methodology. The Centers of Disease Control and Prevention/American Academy of Periodontology definition was used for periodontitis. HPV typing was performed using polymerase chain reaction with modified L1 consensus primers (MY09/MY11).

3 Results

26.5% of adults reported lifetime use of marijuana, 2.7% were frequent users (lifetime use ≥ 26 times, past year use ≥ 6 times, and past 30‐day use ≥2 times), 5.7% had oral HPV infection, and 20.1% had severe periodontitis. The multivariate logistic regression analysis showed that frequent marijuana users were more likely to have severe periodontitis (OR = (2.93, 95%: 1.08–7.96)) than never/once lifetime users after adjusting for age, sex, healthcare coverage, smoking, binge drinking, number of oral sex partners, and oral HPV infection. However, frequent marijuana use was not associated with oral HPV infection.

4 Conclusion

Marijuana use was associated with periodontitis, but not with oral HPV infection. Further evaluation of the role of marijuana use in oral HPV infection and periodontitis may inform novel preventive public health strategies, as marijuana users could be at increased risk of oral cancer.     

Variant haplotypes at XRCC1 and risk of oral leukoplakia in HPV non-infected samples

Background:  One of the mechanisms in human papillomavirus (HPV)-related carcinogenesis is inhibition of DNA repair by HPV oncoprotein. In this study, we investigated whether polymorphisms at XRCC1 , one of the DNA repair loci, could modulate the risk of tobacco-related leukoplakia and cancer in HPV-infected individuals.
Methods:  Tissue DNA from 83 oral cancer, 91 leukoplakia and 100 healthy controls were screened for HPV 16/18 infection and polymorphisms at XRCC1 by PCR–RFLP to estimate the risk of diseases independently and jointly.
Results:  Human papillomavirus infection was significantly associated with increased risk of leukoplakia and cancer (OR = 2.8, 95% CI = 1.2–6.5 and OR = 5.5, 95% CI = 1.6–19, respectively). Independently, genotypes at three polymorphic sites on XRCC1 did not modulate the risk of diseases but pooled variant haplotypes increased the risk of leukoplakia in overall and HPV non-infected (OR = 1.8, 95% CI = 1.2–2.8; OR = 2.2, 95% CI = 1.2–4.0, respectively) samples but not that of cancer.
Conclusion:  The association between variant haplotypes at XRCC1 and risk of leukoplakia is pronounced in non-infected individuals since HPV oncoprotein could inhibit directly the DNA repair activity of XRCC1. But more samples of leukoplakia and cancer are essential to validate these results.     

16型人乳头状瘤病毒E6、E7诱导的人永生化口腔上皮细胞系的建立

目的：建立16型人乳头状瘤病毒（human papiloavirus,HPV16)E6,E7诱导的永生化口腔上皮细胞系，方法：正常口腔上皮细胞转染pLXSNHPV16E6,E7,G418筛选阳性细胞，连续培养建系；Western blot检测细胞HPV16E6，E7蛋白表达；生物学特性检测。集落实验；成瘤实验，结果：细胞连续培养达18个月余，命名为永生化口腔上皮细胞（human immortalized oral epithelial cell,HIOEC) ,HIOEC表达HPV16E6，E7蛋白，角蛋白阳性，透射电镜观察细胞有丰富的张力原纤维，细胞之间形成桥粒，克隆形成率0．77％，裸鼠未成瘤。结论：成功建立了HPV16E6，E7诱导的人永生化口腔上皮细胞系。     

HPV16 E6/E7对永生化口腔上皮细胞p53、p21表达的影响

目的：为了探讨人乳头状瘤病毒(HPV)转化口腔上皮细胞的作用机制，研究HPV16 E6、E7对永生化口腔上皮细胞细胞周期调节因子p53、p21表达的影响。方法：免疫细胞化学法检测HPV16 E6、E7诱导的永生化口腔上皮细胞HIOEC中野生型和突变型p53的表达；Westem印迹检测HIOEC HPV16 E6、E7、p53、p21蛋白表达，并以正常口腔上皮细胞和转染空白载体的口腔上皮细胞为对照。结果：HIOEC细胞表达HPV16 E6、E7蛋白．野生型p53和p21表达水平高于正常口腔上皮细胞和转染空白载体的口腔上皮细胞。结论：p53的失活可能不是HPV16 E6、E7诱导口腔上皮细胞永生化的主要原因。     

Detection of human papilloma virus type 16 DNA in oral squames from normal young adults

We have employed the polymerase chain reaction (PCR) to detect Human Papillomavirus (HPV) type 16 in oral squames and mononuclear cells from 62 healthy young adult volunteers. Two groups were screened for the presence of this virus, but in not all cases was DNA obtained from the scrapes. In the first (n = 30), the results show that 43% of normal individuals harbour HPV 16 (a genital type) in their buccal mucosa, epithelium of dorsum of tongue and hard palate. In the second group (n = 18), 44% of individuals were positive for HPV 16 in their oral epithelial scrapes, while only 6% were positive for the same virus in mononuclear cells. Interestingly, in 2 cases, peripheral blood lymphocyte DNA gave a positive reaction with the HPV 16 primers. To investigate possible HPV infection of lymphocytes, a further 42 lymphocyte samples, taken from the same age group as the epithelial study group, were analysed. None of these lymphocytes were positive for the presence of HPV 16 DNA.     

口腔鳞状细胞癌及白斑人乳头瘤病毒16型感染的临床研究

目的:探讨口腔鳞状细胞癌(OSCC)和白斑(LK)患者人乳头瘤病毒16型(HPV-16)感染和临床病理参数之间的相关性。方法:收集30例OSCC和5例LK患者的组织切片,所有病例均经病理学确诊,提取组织DNA,通过巢式PCR检测HPV-16感染情况。结果:HPV-16与TNM分级之间未见相关性,60岁以下女性患者的HPV-16感染率高于60岁以上女性患者(P=0.024),而男性患者未见HPV-16感染和年龄存在相关性(P=0.649)。结论:60岁以下女性OSCC及LK患者中出现较高的HPV-16感染率,提示这可能是新的致癌危险因子。