HPV16 变异体在新疆地区宫颈癌及癌前病变中的分布研究

目的:研究新疆地区HPV16 E6、E7、LCR基因突变情况,分析HPV16变异体在宫颈癌及癌前病变发生发展中的作用。方法:选择HPV16阳性的宫颈癌及癌前病变患者,提取基因组DNA,利用PCR扩增HPV16 DNA E6、E7基因及LCR区核苷酸片段,正反向测序。与HPV16基因序列分析比对,分析核苷酸突变位点。结果:E6基因突变率为80.00%(92/115)主要突变位点T350G(59.78%)、T178G(18.47%);E7突变率为54.78%(63/115),主要突变位点A647G(33.33%)、T846C(26.98%);LCR突变率为23.48%(27/115),主要突变位点为C24T(74.07%)、C13T(25.92%)。维吾尔族T350G突变率较汉族妇女显著升高,而汉族A647G、T846C、C24T突变率显著高于维吾尔族,差异具有统计学意义(P0.05)。维吾尔族宫颈癌组T350G突变率显著高于炎症组(P0.05),且随病变严重程度增加突变率上升,汉族T350G、A647G、T846C、C24T突变率炎症组、宫颈病变组显著高于宫颈癌组(P0.05),维吾尔族C24T突变率炎症组显著高于宫颈癌组(P0.05),差异均具有统计学意义(P0.05)。结论:HPV16E6、E7突变可能与宫颈病变进展有关,T350G突变可能是维吾尔族宫颈癌高发的原因之一。     

北京地区宫颈癌HPV16上游调控序列、E6、E7癌基因序列初步分析

为检测HPV16上游调控序列(Upstream regulatory region, URR)、E6、E7癌基因变异在北京地区宫颈癌患者癌组织中的分布特征, 探讨该地区宫颈癌发生同HPV16变异株间的相关性, 文章以提取的31例HPV16检测阳性宫颈癌组织DNA为模板, 设计针对性引物扩增URR、E6、E7 3个目的片段, PCR产物直接测序并通过GenBank对比分析变异和分支鉴定情况。在所分析的宫颈癌组织中, URR是突变频率最高的片段, 其次为E7, 最保守的序列为E6。共发现热突变位点8个, 分别为URR序列上G7521A(100%)、C7435G(96.77%)、C24T(45.16%)、A7729C(45.16%)、G7839A(45.16%); E6序列上T178G(41.94%); E7序列上A647G(45.16%)、T846C(45.16%)。HPV16分支分布频率最广的是As型(54.84%), 其次为E型(45.16%)。研究结果提示, HPV16URR序列上G7521A、A7729C、G7839A, E6序列上T178G、T350G, E7序列上A647G、G658A等位点的变异可能与病毒致癌潜能及宫颈癌的发生相关。北京地区宫颈癌患者中As和E型可能是两种最主要的HPV16分支, 这有可能会为HPV疫苗的研制和感染治疗提供有价值的信息。As型和E型病毒在不同年龄组和不同肿瘤分期组的患者中分布频率有差异, 这可能会为揭示宫颈癌年轻化趋势提供新的线索。     

宫颈癌组织人乳头瘤病毒的荧光偏振基因分型

采用荧光偏振人乳头瘤病毒(human papillomavirus,HPV)分型新方法探讨了8种常见型别HPV在陕西宫颈癌患者中的流行情况。首先,用HPV GP5 ／GP6 通用引物PCR扩增65例早期宫颈癌(Ⅱa期内)和72例慢性宫颈炎病变组织DNA粗提物,继之将模板指导的末端延伸反应与荧光偏振检测技术结合(TDI-FP),用GP5 ／GP6 扩增区内的HPV6、11、16、18、31、33、35和58型特异性探针与PCR产物杂交后,荧光素标记的特异碱基(TAMRA-ddTTP或R110-ddGTP)在GP5 ／GP6 产物中相应的模板指导下,掺入延伸至相应探针末端,致使对应的TAMRA或R110 FP值升高,从而对扩增的HPV阳性产物进行HPV分型。65例宫颈癌患者中检出HPV57例,阳性率87．69％,72例慢性宫颈炎患者中检出HPV28例,阳性率38．89％,两组间HPV阳性率有显著性差异。宫颈癌与慢性宫颈炎患者中4种最常见的HPV型别分别是HPV 16(45．6％)、HPV 18(22．8％)、HPV 58(17．5％)、HPV 31(7．02％)和HPV 16(35．7％)、HPV 11(32．1％)、HPV 6(21．4％)、HPV 18(10．7％)。慢性宫颈炎患者中检出的HPV型别57．14％属高危型。HPV 16在两组中均最为多见。中国陕西宫颈疾病患者中HPV感染有其特点,世界范围内少见的HPV 58在陕西宫颈癌与慢性宫颈炎患者中均较为多见,在进行HPV新诊断方法及疫苗研制时应考虑到这种特点。     

新疆维吾尔族妇女宫颈癌组织中乳头瘤病毒16型E6基因的克隆和序列分析

为了分析新疆南部地区维吾尔族妇女宫颈癌组织中HPV16型E6基因结构特点，从中国新疆南部地区维吾尔族妇女宫颈癌活检组织标本中提取DNA，以宫颈癌活检组织标本DNA为模板进行PCR扩增，获得HPV16 E6基因，将其克隆到pUCm-T载体上，并对其进行基因全序列分析.PCR检测结果显示宫颈癌组织中HPV16 E6阳性率为82.35%（14/17）；测序结果显示，新疆株HPV16 E6基因全长456 bp，大小与德国标准株一致.E6基因的第247位碱基发生T→G突变，并由此引起所编码的氨基酸亦发生改变.上述结果表明，中国新疆南部地区维吾尔族妇女宫颈癌患者组织中HPV16 E6的基因结构与德国标准株HPV16 E6基因之间存在差异.     

云南HPV-16型E6、E7基因的突变分析

人乳头瘤病毒(Human papillomavirus,HPV)16型(HPV-16)是引起宫颈癌的一种主要高危型病毒,其2个致癌基因E6和E7的核酸序列变异可能会影响其对宿主细胞的致癌性,已有研究表明其序列突变呈现地域差异性。因此,研究不同地域HPV-16这2个基因的变化情况是宫颈癌流行病学调研的主要内容,也可为研究E6和E7的致癌性积累数据。研究以NCBI登录号为NC_001526.2的HPV-16型病毒的序列为参照,采用Neighbor-joining方法对云南地区74例HPV-16样本的E6、E7的DNA序列构建进化树,结果显示:只有亚洲和欧洲变异亚型,而没有发现非洲1、非洲2、亚-美洲和北美洲这4种变异亚型。DNA序列分析显示:E6的碱基突变以T178G(D25E,59.46%)和T350G(L83V,8.11%)为主,E7的碱基突变主要以A647G(N29S,59.46%)和T846C(同义突变,60.81%)为主。发现E6的新突变有A95G(同义突变,1.35%)和A135G(K11R,1.35%);E7的新突变有C625T(L22F,1.35%)、C627T(同义突变,12.16%)、G689A(G43E,1.35%)、T748G(S63A,1.35%)。此外还发现有一个共突变现象:T178G(D25E,59.46%)-A647G(N29S,59.46%)-T843C(同义突变,21.62%)-T846C(同义突变,60.81%)。     

中国湖北地区HPV16型E6和E7基因变异和进化发生学研究

研究中国湖北地区宫颈癌患者的人乳头瘤病毒16型E6和E7的变异以及HPV16变异体的分布。从宫颈癌患者手术切除标本提取组织DNA,用HPV16 E6和E7特异性引物进行PCR扩增,对扩增的部分E6和E7产物片段进行测序分析。在80例宫颈癌组织DNA中有41例发生E6基因178位核苷酸的突变,突变频率58.75%,相应核苷酸改变为Asp-Glu,E7 647在31例测序样品中有22例发生核苷酸序列A到G改变,使29位氨基酸由Asn变为Ser,突变频率70.97%,结果显示在E6和E7基因的178位和647位核苷酸存在高频率的碱基变异。对E6和E7基因的进化树分析表明,中国湖北地区流行的HPV16病毒株主要为亚洲型变异体(As),其次为欧洲型(E),没有发现非洲-1型(Af-1),非洲-2型(Af-2)和亚洲美洲型(AA)HPV16变异体,中国湖北地区流行的As变异体是否有更高的致宫颈癌的风险还有待于进一步对不同阶段CIN和正常宫颈上皮样品的E6和E7基因进行序列分析和对变异体蛋白进行功能研究。     

宫颈癌组织中人乳头瘤病毒16型E5基因的变异

探讨了HPV16 E5基因突变与宫颈癌发病的关系.应用银染聚合酶链反应-单链构象多态性(PCR-SSCP)分析对50份人宫颈癌活检标本进行基因突变的筛查.PCR检测显示,50例宫颈癌组织中HPV16 E5的检出率为30%(15/50),其中6例宫颈癌HPV16 E5扩增片段在行SSCP分析时发现有泳动变位,突变率为40%(6/15).可见HPV16 E5基因的突变在宫颈癌的发生过程中具有重要作用.     

HLA-Ⅰ表达与维吾尔族妇女宫颈癌前病变及HPV16感染的关系研究

目的:现察人白细胞相关抗原Ⅰ(human leukocyte antigen class Ⅰ, HLA-Ⅰ)表达与维吾尔族妇女宫颈癌前病变进程及高危型HPV16的关系.方法:收集维吾尔族妇女宫颈炎、宫颈内上皮瘤样病(cervical intraepithelial neoplasia, CIN)和宫颈鳞癌患者的石蜡包埋组织标本共148例,提取组织DNA,应用PCR的方法检测HPV阳性及HPV16型别;同时采用免疫组织化学SP法检测HLA-Ⅰ蛋白表达水平.结果:(1)在维吾尔族妇女中HLA-Ⅰ抗原在宫颈炎、CIN Ⅰ-Ⅱ、CIN Ⅲ、SCC组中阳性表达逐渐减少,差异有统计学意义(P<0.001).(2)HLA-Ⅰ的阳性表达下降趋势与宫颈癌临床分期、组织分化程度和淋巴结转移密切相关.(3)HPV在宫颈炎、CIN Ⅰ-Ⅱ、CIN Ⅲ、宫颈癌中的感染率分别为13%、46%、82%、95%,差异有统计学(P<0.001).(4)HPV16在宫颈炎、CIN Ⅰ-Ⅱ、CINⅢ、宫颈癌中的感染率分别为4%、30%、68%、85%,差异有统计学(P<0.001).(5)在HPV 16阳性标本中,存在HLA-Ⅰ表达缺失的占71%(58/82),HPV16感染与HLA-Ⅰ表达呈负相关(r=-0.625,P<0.001).结论:(1)HLA-Ⅰ表达缺陷可能是宫颈病变进展的重要标志,对宫颈癌的预测预警提供依据.(2)HPV16感染在宫颈病变的发展过程中起到了极大的促进作用,是一个很强的致癌因素.(3)HPV16感染与HLA-Ⅰ表达之间的关系对揭示宫颈癌发病机制提供了客观依据.     

HLA-I表达与维吾尔族妇女宫颈癌前病变及HPV16感染的关系研究

目的：观察人白细胞相关抗原I（human leukocyte antigen class I,HLA-I）表达与维吾尔族妇女宫颈癌前病变进程及高危型HPV16的关系。方法：收集维吾尔族妇女宫颈炎、宫颈内上皮瘤样病变（cervical intraepithelial neoplasia,CIN）和宫颈鳞癌患者的石蜡包埋组织标本共148例,提取组织DNA,应用PCR的方法检测HPV阳性及HPV16型别;同时采用免疫组织化学SP法检测HLA-I蛋白表达水平。结果：（1）在维吾尔族妇女中HLA-I抗原在宫颈炎、CINI-II、CINIII、SCC组中阳性表达逐渐减少,差异有统计学意义（P〈0.001）。（2）HLA-I的阳性表达下降趋势与宫颈癌临床分期、组织分化程度和淋巴结转移密切相关。（3）HPV在宫颈炎、CINI-II、CINIII、宫颈癌中的感染率分别为13%、46%、82%、95%,差异有统计学（P〈0.001）。（4）HPV16在宫颈炎、CINI-II、CINIII、宫颈癌中的感染率分别为4%、30%、68%、85%,差异有统计学（P〈0.001）。（5）在HPV16阳性标本中,存在HLA-I表达缺失的占71%（58/82）,HPV16感染与HLA-I表达呈负相关（r=-0.625,P〈0.001）。结论：（1）HLA-I表达缺陷可能是宫颈病变进展的重要标志,对宫颈癌的预测预警提供依据。（2）HPV16感染在宫颈病变的发展过程中起到了极大的促进作用,是一个很强的致癌因素。（3）HPV16感染与HLA-I表达之间的关系对揭示宫颈癌发病机制提供了客观依据。     

HLA-DQB1基因多态和HPV16E7蛋白表达与宫颈癌妇女阴道微生态改变相关性研究

目的 分析HLA-DQB1基因多态和HPV16E7蛋白表达与宫颈癌妇女阴道微生态改变的相关性。方法 选择2020年1月—2020年12月于我院妇科就诊及住院的宫颈炎患者100例和宫颈鳞癌患者100例，宫颈炎及宫颈鳞癌组织均经病理学证实。分析HLA-DQB1基因多态和HPV16E7蛋白表达与宫颈癌妇女阴道微生态改变的相关性。结果 相较于宫颈炎组，宫颈癌患者的pH值异常、菌群密集度、菌群多样性以及BV阳性率均明显升高，差异具有统计学意义(P<0.05)，而TV阳性率和VVC阳性率则无明显差异(P>0.05)。相较于低表达组，HPV16E7蛋白高表达组患者的pH值异常、菌群密集度、菌群多样性、BV阳性率、TV阳性率和VVC阳性率均明显升高，差异具有统计学意义(P<0.05)。相较于宫颈炎患者，宫颈癌组的HLA-DQB1^*04、HLA-DQB1^*06和HLA-DQB1^*09等位基因的携带率存在明显差异(P<0.05)。其中宫颈癌患者HLA-DQB1^*04携带率明显升高，而HLA-DQ...     

Human papillomavirus type 16 E7 peptide-directed CD8+ T cells from patients with cervical cancer are cross-reactive with the coronavirus NS2 protein

Human papillomavirus type 16 (HPV16) E6 and E7 oncoproteins are required for cellular transformation and represent candidate targets for HPV-specific and major histocompatibility complex class I-restricted CD8(+)-T-cell responses in patients with cervical cancer. Recent evidence suggests that cross-reactivity represents the inherent nature of the T-cell repertoire. We identified HLA-A2 binding HPV16 E7 variant peptides from human, bacterial, or viral origin which are able to drive CD8(+)-T-cell responses directed against wild-type HPV16 E7 amino acid 11 to 19/20 (E7(11-19/20)) epitope YMLDLQPET(T) in vitro. CD8(+) T cells reacting to the HLA-A2-presented peptide from HPV16 E7(11-19(20)) recognized also the HLA-A2 binding peptide TMLDIQPED (amino acids 52 to 60) from the human coronavirus OC43 NS2 gene product. Establishment of coronavirus NS2-specific, HLA-A2-restricted CD8(+)-T-cell clones and ex vivo analysis of HPV16 E7 specific T cells obtained by HLA-A2 tetramer-guided sorting from PBL or tumor-infiltrating lymphocytes obtained from patients with cervical cancer showed that cross-reactivity with HPV16 E7(11-19(20)) and coronavirus NS2(52-60) represents a common feature of this antiviral immune response defined by cytokine production. Zero of 10 patients with carcinoma in situ neoplasia and 3 of 18 patients with cervical cancer showed > or =0.1% HPV16 E7-reactive T cells in CD8(+) peripheral blood lymphocytes. In vivo priming with HPV16 was confirmed in patients with cervical cancer or preinvasive HPV16-positive lesions using HLA-A2 tetramer complexes loaded with the E6-derived epitope KLPQLCTEL. In contrast, we could not detect E6-reactive T cells in healthy individuals. These data imply that the measurement of the HPV16 E7(11-19(20)) CD8(+)-T-cell response may reflect cross-reactivity with a common pathogen and that variant peptides may be employed to drive an effective cellular immune response against HPV.     

Apoptosis induced by an antagonist peptide against HPV16 E7 in vitro and in vivo via restoration of p53

Human papilloma virus type 16 (HPV16) E7 is a viral oncoprotein that is believed to play a major role in cervical neoplasia. A novel antagonist peptide against HPV16 E7 was previously selected by phage display screening and the selected peptide was found to have anti-tumor efficacy against HPV16-positive cervical carcinoma through induction of cell cycle arrest. In the current study, to further elucidate the mechanisms of the antagonist peptide, the effects of the peptide on apoptosis are investigated by RT-PCR, Western blotting, MTT assay, TUNEL staining, Annexin V apoptosis assay, flow cytometry, and animal experiments. The antagonist peptide showed obvious anti-tumor efficacy through apoptosis induction, both in HPV16-positive cervical cancer cell lines and tumor xenografts. Our results also revealed that the peptide induced accumulation of cellular p53 and p21, and led to HPV16 E7 protein degradation. In the case of mRNA levels, it resulted in unaltered p53 and HPV16 E7 expression, but increased expression of p21. In contrast, the induction of apoptosis and p53 reactivation effects by the selected peptide were abolished after E7 knocked down with siRNA. These results demonstrate that the selected peptide can induce E7 degradation and lead to marked apoptosis in HPV16-related cancer cells by activating cellular p53 and its target genes, such as p21. Furthermore, the evident therapeutic efficacy obtained from the subcutaneous tumor model experiments in nude mice suggests a therapeutic potential for HPV16-related cancers of the selected peptide. Therefore, this specific peptide may be used to create specific biotherapies for the treatment of HPV 16-positive cervical cancers.     

Expressions of E2 and E7-HPV16 proteins in pre-malignant and malignant lesions of the uterine cervix

Continuous production of the E7 protein from different types of high risk human papilloma virus (HPV) is required for progression of malignancy. We developed antibodies against HPV type 16 E7 and E2 proteins to evaluate their utility as markers for diagnosis during early stages of cervical cancer. Forty biopsies from uterine cervices were diagnosed as low grade intraepithelial lesion (LSIL), high grade intraepithelial lesion (HSIL), squamous carcinoma (SC), in situ adenocarcinoma (ISA) and invasive adenocarcinoma (AC), all of which were infected with HPV 16. Immunohistochemistry was used to investigate the expressions of E7 and E2 (both from HPV 16) and p16. P16 was expressed in eight of 12 LSILs, in all HSILs, in 16 of 18 SC and in all ACs. E2 was expressed in six of 12 LSILs. E7 was positive in eight of 12 LSILs and in all HSIL and carcinomas. The expressions of E2 and E7 of HPV16 related to p16 expression confirmed the value of the viral oncogenic proteins as complementary to histology and support the carcinogenic model of the uterine cervix, because HPVDNA integration into cellular DNA implies the destruction of the gene encoding E2, which suppresses the expression of the E6 and E7 oncoproteins. E2 from HPV16 could be marker for LSILs, while E7 could be a marker for progression of LSILs to HSILs in patients infected by HPV16, because viral typing has little positive predictive value.     

Genetic Variation of Human Papillomavirus Type 16 in Individual Clinical Specimens Revealed by Deep Sequencing

Viral genetic diversity within infected cells or tissues, called viral quasispecies, has been mostly studied for RNA viruses, but has also been described among DNA viruses, including human papillomavirus type 16 (HPV16) present in cervical precancerous lesions. However, the extent of HPV genetic variation in cervical specimens, and its involvement in HPV-induced carcinogenesis, remains unclear. Here, we employ deep sequencing to comprehensively analyze genetic variation in the HPV16 genome isolated from individual clinical specimens. Through overlapping full-circle PCR, approximately 8-kb DNA fragments covering the whole HPV16 genome were amplified from HPV16-positive cervical exfoliated cells collected from patients with either low-grade squamous intraepithelial lesion (LSIL) or invasive cervical cancer (ICC). Deep sequencing of the amplified HPV16 DNA enabled de novo assembly of the full-length HPV16 genome sequence for each of 7 specimens (5 LSIL and 2 ICC samples). Subsequent alignment of read sequences to the assembled HPV16 sequence revealed that 2 LSILs and 1 ICC contained nucleotide variations within E6, E1 and the non-coding region between E5 and L2 with mutation frequencies of 0.60% to 5.42%. In transient replication assays, a novel E1 mutant found in ICC, E1 Q381E, showed reduced ability to support HPV16 origin-dependent replication. In addition, partially deleted E2 genes were detected in 1 LSIL sample in a mixed state with the intact E2 gene. Thus, the methods used in this study provide a fundamental framework for investigating the influence of HPV somatic genetic variation on cervical carcinogenesis.