人乳头瘤病毒16型早基因E6/E7编码区序列变异研究

目的获取人乳头瘤病毒16型早基因E6/E7的编码区序列并进行变异分析,为新型分子诊断方法的研发提供目标序列。方法通过导流杂交基因芯片技术获取人乳头瘤病毒16型感染宫颈脱落细胞。设计特异性引物,扩增人乳头瘤病毒16型早基因E6/E7的编码区序列,克隆后测序并对序列进行变异分析。结果通过导流杂交基因芯片技术进行宫颈脱落细胞的分型检测,获得了人乳头瘤病毒16型感染阳性标本;选择其中3份阳性标本核酸为模板,通过特异性引物均成功扩增出大小介于750 bp和1 000 bp之间的目的序列;分别克隆到T载体上并测序,得到3条人乳头瘤病毒16型早表达基因E6/E7的编码区序列,克隆并测序后向GenBank核酸数据库提交获收录,登录号分别为EU869316、EU869317和EU869318;经BLAST分析,3条序列与GenBank序列PPH16（Accession：K02718）的E6/E7编码区序列一致性均为99%,且存在8种碱基置换,其中4种为同义突变,另4种则可引起所编码的相应氨基酸残基改变。结论本研究得到了与HPV高危型16型PPH16高度相似的E6/E7编码序列,为HPV致病机制和新型分子检测方法研究奠定了基础。     

HPV16 E6/E7基因及蛋白表达与宫颈癌的相关性研究

目的研究人乳头状瘤病毒16型（HPV16）E6／E7基因及其蛋白表达在宫颈疾病及其癌变中的作用。方法运用PCR技术检测51例宫颈癌（癌症组）、20例富颈上皮瘤变（CIN）Ⅱ～Ⅲ级（CIN组）、20例宫颈炎（炎症组）患者病变组织中HPV16 E6／E7基因，并运用免疫组化SP法检测癌症组癌组织中HPV16E6、E7的表达情况。结果癌症组、CIN组、炎症组HPV16 E6检出率分别为5％、35％、45％．后两者明显高于前者（P〈0．05），HPV16 E7检出率分别为65％、75％、68．6％，P均〉0．05；癌症组45例HPV16 E6和42例E7蛋白阳性表达（88．2％、82．3％）。HPV16 E6蛋白表达与临床分期、肿瘤分化程度和淋巴结有无转移均无相关性（P〉0．05），HPV16 E7蛋白表达与临床分期和淋巴结有无转移相关（P〈0．05），与肿瘤分化程度无相关性（P〉0．05）。结论HPV16 E6／E7基因与宫颈疾病及其癌变的关系密切。     

宫颈细胞 HPV E6／E7 mRNA 检测在宫颈病变诊断中的价值

目的：评价高危型人乳头状瘤病毒（ HPV） E6/E7 mRNA检测对宫颈病变的诊断价值。方法520例患者采用b-DNA技术检测HPV E6/E7 mRNA,并用宫颈液基细胞学（ TCT）行宫颈细胞学检查,对其中任何一项阳性者做阴道镜下宫颈活组织检查,以组织病理为金标准,计算HPV E6/E7 mRNA阳性对高级别宫颈上皮内瘤样病变（ CIN）、宫颈浸润癌诊断的灵敏度、特异度、阳性预测值、阴性预测值,并与TCT检查进行比较。结果520例患者中HPV E6/E7 mRNA阳性158例, TCT异常222例。 TCT 异常者中HPV E6/E7 mRNA阳性率较TCT 正常者中HPV E6/E7 mRNA阳性率高（P＜0．05）。146例慢性宫颈炎、CINⅠ级患者与124例高级别CIN、宫颈浸润癌患者中HPV E6/E7 mRNA阳性率比较,P＜0．05。 HPV E6/E7 mRNA阳性对高级别CIN及宫颈浸润癌诊断的灵敏度、特异度、阳性预测值、阴性预测值分别为74．19％、83．33％、58．23％、71．43％,TCT 检查分别为81．53％、69．44％、81．45％、92．28％,两者特异度及阳性预测值比较, P均＜0．05。结论在宫颈癌筛查中检测高危型HPV E6/E7 mRNA对预测高级别CIN,尤其对评估癌症风险有重要的临床价值。     

宫颈癌组织中HPV16型E6/E7序列突变分析

目的：分析泉州地区宫颈癌患者HPV16型E6/E7序列突变情况,探讨其与宫颈癌发生的相关性。方法：取35例HPV16阳性的宫颈癌组织标本,采用PCR法扩增E6、E7全长基因。PCR产物直接测序,并与野生型序列进行比对。分析E6、E7基因的变异情况。结果：E6、E7基因的突变率分别为91.4%和89.2%。E6基因中有10个位点为错义突变, 2个位点为无义突变。氨基酸突变频率最高的是D25E（77.1%）。E7基因中共发现5个突变位点,有2个位点为错义突变,3个位点为无义突变,突变频率最高是N29S和无义突变T846C（均为75.0%）。结论：HPV16 E6、E7基因中最常见突变位点D25E、N29S和T846C可能与宫颈癌的发生密切相关,可为研究针对中国人群的HPV疫苗提供一定的线索。     

Identification of High-Risk Human Papillomavirus DNA,p16, and E6/E7 Oncoproteins in Laryngeal and Hypopharyngeal Squamous Cell Carcinomas

Human papillomavirus (HPV) was proven to play a significant role in cancer development in the oropharynx. However, its role in the development of laryngeal (LSCC) and hypopharyngeal squamous cell carcinoma (HPSCC) remains to be clarified. High-risk HPV (HR-HPV) viral proteins E6 and E7 are considered to be pertinent to HPV-related carcinogenesis. Hence, our aim was to estimate LSCC and HPSCC for HR-HPV DNA, p16, and E6/E7 oncoprotein status by using molecular virology and immunohistochemistry methods. The prevalence of HPV16 infection was 22/41 (53.7%) and 20/31 (64.5%) for LSCC and HPSCC, accordingly. The majority of HPV16+ tumor samples were stage III or IV. In most samples, the presence of either HPV16 E6 or HPV16 E7 viral protein in dysplastic or tumor cells was confirmed using immunohistochemistry. Our results suggest a high prevalence of HPV16 as a primary HR-HPV type in LSCC and HPSCC. The lack of HPV E6/E7 oncoproteins in some tumor samples may suggest either the absence of viral integration or the presence of other mechanisms of tumorigenesis. The utilization of p16 IHC as a surrogate marker of HR-HPV infection is impractical in LSCC and HPSCC.     

The Subcellular Localisation of the Human Papillomavirus (HPV) 16 E7 Protein in Cervical Cancer Cells and Its Perturbation by RNA Aptamers

Human papillomavirus (HPV) is the most common viral infection of the reproductive tract, affecting both men and women. High-risk oncogenic types are responsible for almost 90% of anogenital and oropharyngeal cancers including cervical cancer. Some of the HPV “early” genes, particularly E6 and E7, are known to act as oncogenes that promote tumour growth and malignant transformation. Most notably, HPV-16 E7 interacts with the tumour suppressor protein pRb, promoting its degradation, leading to cell cycle dysregulation in infected cells. We have previously shown that an RNA aptamer (termed A2) selectively binds to HPV16 E7 and is able to induce apoptosis in HPV16-transformed cervical carcinoma cell lines (SiHa) through reduction of E7 levels. In this study, we investigated the effects of the A2 aptamer on E7 localisation in order to define its effects on E7 activity. We demonstrate for the first time that E7 localised to the plasma membrane. In addition, we show that A2 enhanced E7 localisation in the ER and that the A2-mediated reduction of E7 was not associated with proteasomal degradation. These data suggest that A2 perturbs normal E7 trafficking through promoting E7 ER retention.     

HPV16/18E6和P53基因蛋白在喉鳞癌中的表达及其相关性研究

目的探讨人乳头瘤病毒16/18型早期蛋白E6(HPV16/18 E6)、P^53基因蛋白在喉鳞癌(LSCC)中的表达及其相关性.方法免疫组化SABC法检测HPV16/18E6和P^53基因蛋白在LSCC及声带息肉中的表达.结果 HPV16/18E6在声带息肉中未见表达,在LSCC中的表达率为40.0%,差异有显著性(P＜0.05). P^53基因蛋白在声带息肉与LSCC中的表达率分别为6.66%和66.2%,差异有显著性(P＜0.05).HPV16/18E6及 P^53基因蛋白的表达与LSCC临床分期、淋巴结转移有关.二者的表达无明显相关性.结论 HPV16/18型感染和P^53基因异常与LSCC发生、发展有关.HPV16/18E6与P^53基因功能异常无明显相关性.     

新疆哈萨克族食管癌组织中乳头瘤病毒16型E6E7基因的研究

为了解HPV16感染后E6E7基因变化在哈萨克族食管癌发病中的作用 ,以及HPV16E6E7基因与食管癌病理组织分级的关系 ,采用聚合酶链 (PCR)技术 ,检测 82例食管癌及癌旁正常食管粘膜组织中HPV 16E6E7基因差别。食管癌、癌旁正常粘膜组HPV16E6E7基因的检出率分别为 3 4. 15 % ( 14 /4 1)和 19. 5 1% ( 8/4 1) ,63 . 41% ( 2 6/4 1)和48. 78% ( 2 0 /4 1) ,差别均无显著性 (P >0 . 0 5 )。然而 ,在食管癌组织的高分化组、中低分化组中HPV16E6E7的检出率分别为 7. 69% ( 1/13 )和 46. 43 % ( 13 /2 8) ,3 8. 46% ( 5 /13 )和 75 % ( 2 1/2 8) ,差别均有统计学意义 (P <0 .0 5 )。提示HPV16E6E7基因与哈萨克族食管癌的发生及癌组织分级密切相关。     

Human papillomavirus 16 E6 expression disrupts the p53-mediated cellular response to DNA damage.

Infection with certain types of human papillomaviruses (HPV) is highly associated with carcinomas of the human uterine cervix. However, HPV infection alone does not appear to be sufficient for the process of malignant transformation, suggesting the requirement of additional cellular events. After DNA damage, normal mammalian cells exhibit G1 cell-cycle arrest and inhibition of replicative DNA synthesis. This mechanism, which requires wild-type p53, presumably allows cells to undertake DNA repair and avoid the fixation of mutations. We directly tested whether the normal response of cervical epithelial cells to DNA damage may be undermined by interactions between the E6 protein expressed by oncogenic HPV types and wild-type p53. We treated primary keratinocytes with the DNA-damaging agent actinomycin D and demonstrated inhibition of replicative DNA synthesis and a significant increase in p53 protein levels. In contrast, inhibition of DNA synthesis and increases in p53 protein did not occur after actinomycin D treatment of keratinocytes immortalized with HPV16 E6/E7 or in cervical carcinoma cell lines containing HPV16, HPV18, or mutant p53 alone. To test the effects of E6 alone on the cellular response to DNA damage, HPV16 E6 was expressed in the carcinoma cell line RKO, resulting in undetectable baseline levels of p53 protein and loss of the G1 arrest that normally occurs in these cells after DNA damage. These findings demonstrate that oncogenic E6 can disrupt an important cellular response to DNA damage mediated by p53 and may contribute to the subsequent accumulation of genetic changes associated with cervical tumorigenesis.     

广州东部HPV基因型分布及其优势基因型E6／E7核酸序列分析

目的研究广州东部人乳头瘤病毒基因型分布特征,并获取优势基因型早基因E6／E7的核酸序列,进行变异分析,为本课题组下一步新型分子诊断方法的研发提供目标序列。方法通过导流杂交基因芯片技术进行宫颈脱落细胞标本的人乳头瘤病毒基因分型检测,分析本地区基因型分布特征,确定优势基因型;根据GenBank序列设计特异性引物,用于扩增优势基因型的早基因E6／E7的编码区序列,克隆后测序并对序列进行变异分析。结果通过导流杂交基因芯片技术进行宫颈脱落细胞标本的分型检测,检测了536份宫颈脱落细胞标本,HPV阳性占27.2％（146／536）,其中多基因型感染占29.5％（43／146）,高危型感染中52型为优势基因型,频数达23.3％（37／159）。HPV感染与52型HPV感染的年龄分布显示低年龄组（即A组,≤25岁）妇女最高。3份52型HPV感染阳性标本的核酸模板,通过特异性引物均成功扩增出大小接近750bp的目的序列;分别克隆到T载体上并测序,得到3条人乳头瘤病毒52型早表达基因E6／E7的编码区序列,克隆后测序并对序列进行变异分析;3条序列经BLAST分析,与GenBank数据库HPV52型序列（Accession：X74481）的E6／E7编码区序列一致性均为99％,三条序列（EU924143、EU924144、EU924145）存在6种碱基置换,其中2种可引起所编码的相应氨基酸残基改变。结论本研究可确认广州东部地区妇女宫颈感染HPV中A组（17-25岁）具有最高的感染率;宫颈感染HPV的优势基因型为52型;我们通过克隆策略得到了与HPV高危型52型X74481高度相似的E6／E7编码序列,为课题组后续进行的HPV致病机制和新型分子检测方法研究提供了重要基础。     

Prevalence of anal infection due to high-risk human papillomavirus and analysis of E2 gene integrity among women with cervical abnormalities

Background

High-risk human papillomaviruses (HR-HPV) infection has been associated with 90% of anal cancer cases. Women with abnormal cytology are a high-risk group to develop anal neoplasia. The aim of this study is to describe the prevalence and epidemiology of HR-HPV 16, 18, 45, and 58 anal infections in women with cervical abnormalities, as well as to assess E2 gene integrity.

Non-Metabolic Functions of PKM2 Contribute to Cervical Cancer Cell Proliferation Induced by the HPV16 E7 Oncoprotein

Pyruvate kinase M2 (PKM2) mainly catalyzes glycolysis, but it also exerts non-glycolytic functions in several cancers. While it has been shown to interact with the human papillomavirus 16 (HPV16) E7 oncoprotein, the functional significance of PKM2 in HPV-associated cervical cancer has been elusive. Here, we show that HPV16 E7 increased the expression of PKM2 in cervical cancer cells. TCGA data analyses revealed a higher level of PKM2 in HPV⁺ than HPV⁻ cervical cancers and a worse prognosis for patients with high PKM2 expression. Functionally, we demonstrate that shRNA-mediated PKM2 knockdown decreased the proliferation of HPV⁺ SiHa cervical cancer cells. PKM2 knockdown also inhibited the E7-induced proliferation of cervical cancer cells. ML265 activating the pyruvate kinase function of PKM2 inhibited cell cycle progression and colony formation. ML265 treatments decreased phosphorylation of PKM2 at the Y105 position that has been associated with non-glycolytic functions. On the contrary, HPV16 E7 increased the PKM2 phosphorylation. Our results indicate that E7 increases PKM2 expression and activates a non-glycolytic function of PKM2 to promote cervical cancer cell proliferation.     

局部细胞中HPVl6基因表达量及突变与其宫颈持续感染的关系

目的探讨宫颈脱落细胞中人乳头瘤病毒（HPV）16基因的表达量及突变与其宫颈持续感染的关系。方法选取96例HPVl6感染患者,其中33例宫颈脱落细胞HPVl6持续阳性（持续感染组）,63例6个月后复查转为阴性（非持续感染组）。采用半定量PCR技术检测两组（宫颈脱落细胞中）HPVl6E5、E6、E7及长控制区（LCR）基因表达量,基因测序法检测HPVl6E5、E6、E7及LCR基因突变。结果持续感染组HP~16E5、E6、E7、LCR基因表达量分别为0．20±0．02、0．30±0．02、0．19±0．01、0．53±0．02,非持续感染组分别为0．17±0．02、0．27±0．03、0．16±O．06、0．504-0．04,两组比较P均〉0．05。持续感染组与非持续感染组3978A→c（144L）位点突变例数分别为33、63例,4041A→G（165V）位点突变例数分别为33、63例,4076A—T（同义突变）位点突变例数分别为28、31例;两组4076A→T突变例数比较,P〈0．01。持续感染组与非持续感染组E6基因178T→G（D25E）位点突变例数分别为10、4例,两组比较,P〈0．05;持续感染组与非持续感染组E7基因647A→G（N29S）与846T→c（同义突变）联合突变例数分别为9、8例,两组比较,P〉0．05;持续感染组与非持续感染组7761c→T位点突变例数分别为33、63例,P〉0．05;7727A→c位点突变例数分别为14、4例,两组比较,P〈0．01。结论宫颈脱落细胞中HPVl6基因表达量与持续性感染无密切关系,HPVl6E5、E6、LCR基因突变与宫颈持续性感染有关,其中HPVl6E54076A→T（同义突变）、E6178T→G（D25E）与LCR7727A→c突变点可能是导致HPVl6持续感染的关键突变位点。     

Dendritic cell-based tumor vaccine for cervical cancer I: in vitro stimulation with recombinant protein-pulsed dendritic cells induces specific T cells to HPV16 E7 or HPV18 E7

Purpose Human papillomavirus (HPV) type 16 and 18 are the most prevalent genotypes in cervical cancers. The viral oncoproteins E6 and E7 are considered to be tumor-specific targets for immunotherapy. HPV E7 antigen-loaded dendritic cells (DC) were evaluated as cellular tumor vaccine.Methods Autologous monocyte-derived DCs loaded with recombinant HPV16 or HPV18 E7 oncoprotein were used to induce in vitro a specific T cell response. Specificities of activated T cells were determined.Results E7-specific T cells could be identified in 18/20 T cell lines from healthy blood donors. CD4⁺ T cell responses (13/16) were found by proliferation assay. CD8⁺ CTLs (12/18) were detectable by interferon-gamma (IFN-) ELISpot analysis. Seven donors reacted in both assays and only 2/20 T cell lines did not react in any assay. Thus, specific T cells could be activated in >80% of healthy individuals. T cell lines from suitable donors were specific for HLA-A*0201-restricted epitopes. Furthermore, HPV E7 antigen-loaded DC stimulated specific responses in freshly isolated tumor infiltrating lymphocyte (TIL) populations of cervical cancer patients.Conclusion Autologous dendritic cells loaded with HPV E7 protein can induce T cell responses in healthy individuals by in vitro stimulation and evoke responses in TIL from cervical cancer biopsies. Since there are no limitations with respect to specific HLA-haplotypes, these findings may be a basis for the development of a therapeutic protein-based DC tumor vaccine against cervical cancer for HPV16- and HPV18-positive patients.Abbreviations B-LCL B lymphoblastoid cell line - CTL Cytotoxic T lymphocyte - DC Dendritic cell - IFN- Interferon-gamma - IL Interleukin - GM-CSF Granulocyte/macrophage-colony stimulating factor - HPV Human Papillomavirus - HSA human serum albumin - PBL Peripheral blood lymphocytes - PBMC Peripheral blood mononuclear cells - SD standart deviation - TIL Tumor infiltrating lymphocytes - TNF- Tumor necrosis factor-alpha