Clinical evaluation of human papillomavirus 16/18 oncoprotein test for cervical cancer screening and HPV positive women triage

The prognostic role of tumor‐infiltrating tryptase⁺ mast cells in human solid tumors remains controversial. Herein, we conducted a meta‐analysis including 28 published studies with 4224 patients identified from PubMed and EBSCO to assess the prognostic impact of tumor‐infiltrating tryptase⁺ mast cells in human solid tumors. We found that tryptase⁺ mast cell infiltration significantly decreased overall survival (OS) and disease‐free survival (DFS) in all types of solid tumors. In stratified analyses, tryptase⁺ mast cell infiltration was significantly associated with worse OS in non‐small cell lung cancer, hepatocellular carcinoma and 5‐year survival in colorectal cancer. And these cells were inversely associated with DFS in hepatocellular and colorectal cancer. In addition, high density of intratumoral tryptase⁺ mast cells significantly correlated with lymph node metastasis of solid tumor. In conclusion, Tryptase⁺ mast cell infiltration leads to an unfavorable clinical outcome in solid tumors, implicating that it is a valuable biomarker for prognostic prediction for human solid malignances and targeting it may have a potential for effective treatment.     

Human papillomavirus E7 protein detection as a method of triage to colposcopy of HPV positive women,in comparison to genotyping and cytology. Final results of the PIPAVIR study

The objective of the presented cross‐sectional‐evaluation‐screening study is the clinical evaluation of high‐risk(hr)HPVE7‐protein detection as a triage method to colposcopy for hrHPV‐positive women, using a newly developed sandwich‐ELISA‐assay. Between 2013‐2015, 2424 women, 30‐60 years old, were recruited at the Hippokratio Hospital, Thessaloniki/Greece and the Im Mare Klinikum, Kiel/Germany, and provided a cervical sample used for Liquid Based Cytology, HPV DNA genotyping, and E7 detection using five different E7‐assays: “recomWell HPV16/18/45KJhigh”, “recomWell HPV16/18/45KJlow”, “recomWell HPV39/51/56/59”, “recomWell HPV16/31/33/35/52/58” and “recomWell HPVHRscreen” (for 16,18,31,33,35,39,45,51,52,56,58,59 E7), corresponding to different combinations of hrHPVE7‐proteins. Among 1473 women with eligible samples, those positive for cytology (ASCUS+ 7.2%), and/or hrHPV DNA (19.1%) were referred for colposcopy. Cervical Intraepithelial Neoplasia grade 2 or worse (CIN2+) was detected in 27 women (1.8%). For HPV16/18‐positive women with no triage, sensitivity, positive predictive value (PPV) and the number of colposcopies needed to detect one case of CIN2+ were 100.0%, 11.11% and 9.0 respectively. The respective values for E7‐testing as a triage method to colposcopy ranged from 75.0‐100.0%, 16.86‐26.08% and 3.83‐5.93. Sensitivity and PPV for cytology as triage for hrHPV(non16/18)‐positive women were 45.45% and 27.77%; for E7 test the respective values ranged from 72.72‐100.0% and 16.32‐25.0%. Triage of HPV 16/18‐positive women to colposcopy with the E7 test presents better performance than no triage, decreasing the number of colposcopies needed to detect one CIN2+. In addition, triage of hrHPV(non16/18)‐positive women with E7 test presents better sensitivity and slightly worse PPV than cytology, a fact that advocates for a full molecular screening approach.     

Lower cost strategies for triage of human papillomavirus DNA‐positive women

Using human papillomavirus (HPV) testing for cervical cancer screening in lower‐resource settings (LRS) will result in a significant number of screen‐positive women. This analysis compares different triage strategies for detecting cervical precancer and cancer among HPV‐positive women in LRS. This was a population‐based study of women aged 25–65 years living in China (n = 7,541). Each woman provided a self‐collected and two clinician‐collected specimens. The self‐collected and one clinician‐collected specimen were tested by two HPV DNA tests—careHPV? and Hybrid Capture 2; the other clinician‐collected specimen was tested for HPV16/18/45 E6 protein. CareHPV?‐positive specimens were tested for HPV16/18/45 DNA. HPV DNA‐positive women underwent visual inspection with acetic acid (VIA) and then colposcopic evaluation with biopsies. The performance for detection of cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) among HPV DNA‐positive women was assessed for different triage strategies: HPV16/18/45 E6 or DNA detection, VIA, colposcopic impression, or higher signal strength (≥10 relative light units/positive control [rlu/pc]). The percent triage positive ranges were 14.8–17.4% for VIA, 17.8–20.9% for an abnormal colposcopic impression; 7.9–10.5% for HPV16/18/45 E6; 23.4–28.4% for HPV16/18/45 DNA; and 48.0–62.6% for higher signal strength (≥10 rlu/pc), depending on the HPV test/specimen combination. The positivity for all triage tests increased with severity of diagnosis. HPV16/18/45 DNA detection was approximately 70% sensitive and had positive predictive values (PPV) of approximately 25% for CIN3+. HPV16/18/45 E6 detection was approximately 50% sensitive with a PPV of nearly 50% for CIN3+. Different triage strategies for HPV DNA‐positive women provide important tradeoffs in colposcopy or treatment referral percentages and sensitivity for prevalent CIN3+.     

高危型HPV E6/E7 mRNA检测对宫颈高级别病变的预警分流价值

目的:通过比较检测HPV E6/E7 mRNA和HPV DNA两种HPV检测方法对宫颈高级别病变的检出能力,探讨HPV E6/E7 mRNA检测在宫颈癌筛查中的预警分流价值。方法:采集2016年7月至2017年6月就诊于我院接受宫颈癌筛查的1 515例女性宫颈脱落细胞,利用转录介导扩增法检测高危型HPV E6/E7 mRNA（n=505）和PCR+膜杂交法检测HPV DNA（n=1 010）,以组织病理学诊断为金标准,比较两种检测方法对宫颈高级别病变检出率。结果:利用HPV E6/E7 mRNA检测组阴道镜转诊率32.69%（17/52）、HPV DNA检测组阴道镜转诊率10.62%（12/113）,差异有统计学意义（P＝0.001）;HPV E6/E7 mRNA检测组CIN2+的检出率42.42%;HPV DNA组 CIN2+的检出率28.16%,差异有统计学意义（P＝0.034）。结论:与HPV DNA检测方法相比,HPV E6/E7 mRNA检测对CIN2+病变预警分流价值较高。     

Evaluation of a validated methylation triage signature for human papillomavirus positive women in the HPV FOCAL cervical cancer screening trial

Human papillomavirus (HPV)-based cervical cancer screening requires triage of HPV positive women to identify those at risk of cervical intraepithelial neoplasia grade 2 (CIN2) or worse. We conducted a blinded case–control study within the HPV FOCAL randomized cervical cancer screening trial of women aged 25–65 to examine whether baseline methylation testing using the S5 classifier provided triage performance similar to an algorithm relying on cytology and HPV genotyping. Groups were randomly selected from women with known HPV/cytology results and pathology outcomes. Group 1: 104 HPV positive (HPV+), abnormal cytology (54 CIN2/3; 50 <CIN2); Group 2: 103 HPV+, normal cytology with HPV persistence at 12 mo. (53 CIN2/3; 50 <CIN2); Group 3: 50 HPV+, normal cytology with HPV clearance at 12 mo. (assumed <CIN2), total n=257. For the combined groups, S5 risk score CIN2/3 relative sensitivity, specificity and positive predictive value (PPV) were compared with other triage approaches. Methylation showed a highly significant increasing trend with disease severity. For CIN3, S5 relative sensitivity and specificity were: 93.2% (95%CI: 81.4–98.0) and 41.8% (35.2–48.8), compared to 86.4% (75.0–95.7) and 49.8% (43.1–56.6) respectively for combined abnormal cytology/HPV16/18 positivity (differences not statistically significant at 5% level); adjusted PPVs were 18.2% (16.2–20.4) and 19.3% (16.6–22.2) respectively. S5 was also positive in baseline specimens from eight cancers detected during or after trial participation. The S5 methylation score had high sensitivity and PPV for CIN3, compatible with US and European thresholds for colposcopy referral. Methylation signatures can identify most HPV positive women at increased risk of cervical cancer from their baseline screening specimens.     

Risk stratification and long‐term risk prediction of E6 oncoprotein in a prospective screening cohort in China

E6 oncoprotein is a necessary agent of HPV driven oncogenic transformation. This study is aimed at evaluating the risk stratification potency of HPV 16/18 E6 oncoprotein (E6) as a triage method for HPV positivity. Moreover, it also acts as a predictor of cervical intraepithelial neoplasia grade 3 or worse (CIN3+). The screening cohort of 1,997 women was followed for a 15 year period in approximate five‐year intervals. Participants were concurrently screened by HPV DNA testing (HC2), liquid based cytology (LBC), visual inspection with acetic acid (VIA) and were referred to colposcopy and biopsy if any tests reflected positive. E6 was performed on cervical samples collected from this cohort in 2005 and 2014. The ability of E6 to predict CIN3+ risk after the five‐ and ten‐year interval was evaluated. Among HPV positive women in 2005, E6 indicated the lowest positive rate (9.9%) compared to LBC (48.4%) and VIA (28.0%), however, a higher prevalence rate (10.3%) and 10‐year cumulative incidence rate (53.0%) of CIN3+ were detected among women who were E6 positive. Meanwhile, only 4.2% and 2.9% of women with abnormal LBC and positive VIA were diagnosed as prevalent CIN3+ in 2005, 23.0% and 16.5% developed to CIN3+ after year 10, respectively. Strong associations were found between precedent and subsequent HPV persistence and E6 oncoprotein expression (OR_adjusted = 40.0 and 21.2, respectively). E6 oncoprotein could serve as a low‐cost, highly specific, strongly indicative point‐of‐care method in the triage and treatment of HPV positive women.     

The human papillomavirus E6 and E7 inducible oncogene, hWAPL, exhibits potential as a therapeutic target

Here we show that human papillomavirus (HPV) E6 and E7 oncoproteins induce hWAPL expression. In addition, small interfering RNA (siRNA) of hWAPL suppressed the growth of tumours derived from SiHa cells in nude mice. Thus, hWAPL may be one of the effective targets of uterine cervical cancer therapy.     

Selective suppression of monocyte chemoattractant protein-1 expression by human papillomavirus E6 and E7 oncoproteins in human cervical epithelial and epidermal cells

Infection of cervical keratinocytes by high-risk HPV is involved in the etiology of cervical carcinoma. Since viral products are immunogenic, development of cancer may require suppression of immune responses directed against infected epithelial cells. Many markers of host immune effector responses decrease as cervical intraepithelial neoplasia progresses. Among these is epithelial cell expression of the chemokine MCP-1, though the mechanism for its suppression is unclear. Here, we show that the E6 and E7 viral oncogenes from high-risk HPV, individually and together, suppress MCP-1 expression in primary epithelial cells derived from the female genital tract. This is not a consequence of global suppression of chemokine expression since other chemokines, including IP-10, IL-8 and RANTES, were less affected. Furthermore, 4 of 6 HPV-positive cervical carcinoma cell lines did not express MCP-1. Our data indicate that suppression of MCP-1 expression is part of the program of high-risk HPV E6/E7-induced transformation of primary epithelial cells. These observations are consistent with a model in which MCP-1 expression by infected keratinocytes, which would stimulate an immune attack on HPV-transformed cells, is suppressed for invasive cervical cancer to appear.     

液基细胞学联合 HPV mRNA 检测对宫颈癌的诊断价值

目的：探索高危型 HPV E6／E7 mRNA 和 HPV E6／E7 DNA 两种检测方法分别联合宫颈薄层液基细胞学检查（TCT）应用于宫颈癌早期诊断的临床意义。方法：选择2013年1月至2014年12月我院妇科门诊就诊行 TCT 检查的259例检测标本,对高危型 HPV E6／E7 mRNA 和 HPV E6／E7 DNA 进行检测,结合 xb 细胞病理学分级和组织病理学诊断进行统计分析。结果：纳入研究的259例患者中 HPV E6／E7 mRNA 检测阳性率为35．1％（91／259）,HPV E6／E7 DNA 检测阳性率为52．1％（135／259）。NILM、ASCUS、LSIL、HSIL 四种细胞病理学分级 HPV E6／E7 mRNA 和 HPV E6／E7 DNA 检出率分别为23．5％、29．4％、64．3％、66．7％和32．4％、52．5％、61．9％、83．3％。对于正常组织,HPV E6／E7 mRNA 的敏感度、准确度和阳性预测值均低于HPV E6／E7 DNA（P ＜0．05）,但特异度和阴性预测值高于 HPV E6／E7 DNA（P ＜0．001）。对于 CIN1组织, HPV E6／E7 mRNA 的敏感度、特异度和阳性预测值均低于 HPV E6／E7 DNA（P ＜0．05）,但准确度和阴性预测值高于 HPV E6／E7 DNA（P ＜0．001）。在 CIN2和 CIN3组织中,HPV E6／E7 mRNA 的准确度和阴性预测值均高于 HPV E6／E7 DNA（P ＜0．001）,HPV E6／E7 mRNA 的敏感度、特异度、阳性预测值与 HPV E6／E7 DNA 无统计学差异（P ＞0．05）。结论：高危型 HPV E6／E7 mRNA 检测能更准确地反映病毒感染后的活化状态,HPV宫颈薄层液基细胞学检查联合高危型 HPV E6／E7 mRNA 检测可提高宫颈癌早期筛查的准确性。     

HPV E6/E7 mRNA和HPV DNA检测技术在宫颈上皮内瘤变中的诊断价值分析

目的比较人乳头瘤病毒(HPV)E6/E7 mRNA和HPV DNA检测技术对宫颈上皮内瘤变(CIN)2级及以上(CIN2+)患者的诊断价值,并评价HPV E6/E7 mRNA检测结果在不同实验室间的一致性。方法采用HPV E6/E7 mRNA和HPV DNA检测技术对212例门诊体检的健康者和住院的宫颈病变患者的宫颈脱落细胞学标本进行检测。以病理诊断结果为金标准,评价两种检测技术诊断CIN2+的灵敏度和特异度。北京市迪安中心实验室和北京市怀柔妇幼保健院实验室均采用HPV E6/E7 m RNA检测技术检测同一批标本,评价实验室间检测的一致性。结果HPV E6/E7 m RNA检测的阳性率为38.7%,与HPV DNA的阳性率43.9%比较,差异无统计学意义(P﹥0.05)。HPV E6/E7 mRNA和HPV DNA的检测阳性率均随着病理分级的升高而增加(P<0.01)。HPV E6/E7mRNA检测CIN2+的灵敏度为92.96%,与HPV DNA的90.14%相比,差异无统计学意义(P﹥0.05),而HPV E6/E7mRNA检测CIN2+的特异度为88.65%,高于HPV DNA的79.43%,差异有统计学意义(P<0.05)。两个实验室采用HPV E6/E7 m RNA检测阳性一致的标本例数为78,阴性一致的标本例数为121,总一致率为93.87%,Kappa=0.872,一致性较好。结论与HPV DNA检测技术相比,HPV E6/E7 mRNA检测宫颈病变的特异度更具优势,实验室间重复性检测的一致率较高,有望成为中国宫颈癌HPV筛查的首选方法。     

人乳头瘤病毒E6与宫颈癌

宫颈癌的病因与持续感染人乳头瘤病毒(human papillomavirus,HPV)相关.最近的研究表明,HPV E6在宫颈癌的发生过程中发挥重要作用.本文就HPV E6宫颈癌的发生机制及HPV E6蛋白的表达与宫颈癌的临床意义进行综述.     

DNA methylation markers as a triage test for identification of cervical lesions in a high risk human papillomavirus positive screening cohort

Objective triage strategies are required to prevent unnecessary referrals for colposcopy in population-based screening programs using primary high-risk human papillomavirus (hrHPV) testing. We have identified several DNA methylation markers with high sensitivity and specificity for detection of high-grade cervical intraepithelial neoplasia or worse (CIN2+) in women referred for colposcopy. Our study assessed diagnostic potential of these methylation markers in a hrHPV-positive screening cohort. All six markers (JAM3, EPB41L3, C13orf18, ANKRD18CP, ZSCAN1 and SOX1) showed similar association across histology in the hrHPV-positive cohort when compared to the Dutch cohort (each p > 0.15). Sensitivity for CIN2+ was higher using methylation panel C13orf18/EPB41L3/JAM3 compared to the other 2 panels (80% vs. 60% (ANKRD18CP/C13orf18/JAM3) and 63% (SOX1/ZSCAN1), p = 0.01). For CIN3+ all three methylation panels showed comparable sensitivity ranging from 68% (13/19) to 95% (18/19). Specificity of SOX1/ZSCAN1 panel (84%, 167/200) was considerably higher compared to ANKRD18CP/C13orf18/JAM3 (68%, 136/200, p = 2 × 10⁻⁵) and C13orf18/EPB41L3/JAM3 (66%, 132/200, p = 2 × 10⁻⁷). High negative predictive value (NPV) (91–95% and 96–99%) was observed for CIN2+ and CIN3+, for all three methylation panels, while positive predictive value (PPV) varied from 25 to 40% for CIN2+ and 15–27% for CIN3+. Interestingly, 118/235 samples were negative for all six markers (including 106 controls (89.8%), 6 CIN1 (5.1%), 5 CIN2 (4.2%) and 1 CIN3 (0.8%)). Methylation results from both independent cohorts were comparable as well as high sensitivity for detection of cervical cancer and its high-grade precursors in hrHPV-positive population. Our study therefore validates these methylation marker panels as triage test either in hrHPV-based or abnormal cytology-based screening programs.     

高危型人乳头瘤病毒癌基因E6和E7调节细胞作用靶点的研究进展

高危型人乳头瘤病毒(human papillomavirus,HPV)的感染与多种人类癌症密切相关,其中最典型的是宫颈癌.高危型HPV最重要的两个病毒癌基因为E6和E7,病毒基因组整合到宿主基因组是病毒癌基因E6和E7实现持续表达的一种方式.HPV癌基因E6和E7能够靶向宿主细胞途径,通过这些相互作用,导致HPV发挥其...     

Cytotoxic T Lymphocytes Elicited by Dendritic Cell-Targeted Delivery of Human Papillomavirus Type-16 E6/E7 Fusion Gene Exert Lethal Effects on CaSki Cells

Human papillomavirus (HPV) is the primary etiologic agent of cervical cancer. Consideration of safety andnon human leukocyte antigen restriction, protein vaccine has become the most likely form of HPV therapeuticvaccine, although none have so far been reported as effective. Since tumor cells consistently express the twoproteins E6 and E7, most therapeutic vaccines target one or both of them. In this study, we fabricated DCvaccines by transducing replication-defective recombinant adenoviruses expressing E6/E7 fusion gene ofHPV-16, to investigate the lethal effects of specific cytotoxic T lymphocytes (CTL) against CaSki cells in vitro.Mouse immature dendritic cells (DC) were generated from bone marrow, and transfected with pAd-E6/E7 toprepare a DC vaccine and to induce specific CTL. The surface expression of CD40, CD68, MHC II and CD11cwas assessed by flow cytometry (FCM), and the lethal effects of CTL against CaSki cells were determined byDAPI, FCM and CCK-8 methods. Immature mouse DC was successfully transfected by pAd-E6/E7 in vitro,and the transfecting efficiency was 40%-50%. A DC vaccine was successfully prepared and was used to inducespecific CTL. Experimental results showed that the percentage of apoptosis and killing rate of CaSki cells weresignificantly increased by coculturing with the specific CTL (p <0.05). These results illustrated that a DC vaccinemodified by HPV-16 E6/E7 gene can induce apoptosis of CaSki cells by inducing CTL, which may be used as anew strategy for biological treatment of cervical cancer.     

食管鳞癌中人乳头瘤病毒16型E6、E7和细胞特异性增强子片段的检测

目的:检测食管鳞癌组织中人乳头瘤病毒(HPV)16 E6、E7基因和细胞特异性增强子片段(CTSE).方法:采用聚合酶链反应法(PCR)检测40例食管鳞癌和20例正常食管黏膜中HPV16 E6、E7基因和病毒长控制区内(long control region,LCR)的细胞型特异性增强子(cell type specific enhancer,CTSE).结果:在40例食管鳞癌中,HPV16 的E6、E7基因和CTSE片段的检出率分别是37.5%(15/40)、42.5%(17/40)和40%(16/40),20例正常食管黏膜中E6、E7和CTSE的检出率分别为0%(0/20)、0%(0/20)和5%(1/20),两者均存在显著性差异(P<0.05).CTSE片段分别与E6和E7 基因有明显相关性(P<0.05).食管鳞癌中E6 、E7基因及CTSE的检出率在患者不同性别、年龄、肿瘤浸润程度、淋巴结转移和组织学分级肿瘤中差异均无显著性(P>0.05). 结论:E6和E7基因与CTSE 片段共存于HPV16感染的食管鳞癌组织中,三者可能与食管鳞癌的发生和发展有关.     

HPV16型E6、E7变异与宫颈癌发生发展的研究进展

宫颈癌是全球15 ～44岁女性中第二常见的恶性肿瘤,每年的死亡人数约为265 653人,在中国,宫颈癌的发生率及死亡率仍较高.高危型人乳头状瘤病毒(HPV)持续感染是宫颈癌前病变及宫颈癌发生的必要条件,HPV16是最常见的高危人乳头瘤病毒.HPV16编码的E6和E7蛋白在HPV相关的肿瘤中起关键作用.近年来的研究揭示了HPV16 E6、E7基因的变异引起氨基酸变化可影响E6、E7蛋白与p53、pRb 的结合,进而与宿主细胞恶性转化相关.本文将对近年来HPV16 E6、E7变异在宫颈癌发生发展中的作用作一综述.     

Human papillomavirus type 16 E7 oncoprotein mediates CCNA1 promoter methylation

Human papillomavirus (HPV) oncoproteins drive distinctive promoter methylation patterns in cancer. However, the underlying mechanism remains to be elucidated. Cyclin A1 (CCNA1) promoter methylation is strongly associated with HPV‐associated cancer. CCNA1 methylation is found in HPV‐associated cervical cancers, as well as in head and neck squamous cell cancer. Numerous pieces of evidence suggest that E7 may drive CCNA1 methylation. First, the CCNA1 promoter is methylated in HPV‐positive epithelial lesions after transformation. Second, the CCNA1 promoter is methylated at a high level when HPV is integrated into the human genome. Finally, E7 has been shown to interact with DNA methyltransferase 1 (Dnmt1). Here, we sought to determine the mechanism by which E7 increases methylation in cervical cancer by using CCNA1 as a gene model. We investigated whether E7 induces CCNA1 promoter methylation, resulting in the loss of expression. Using both E7 knockdown and overexpression approaches in SiHa and C33a cells, our data showed that CCNA1 promoter methylation decreases with a corresponding increase in expression in E7 siRNA‐transfected cells. By contrast, CCNA1 promoter methylation was augmented with a corresponding reduction in expression in E7‐overexpressing cells. To confirm whether the binding of the E7–Dnmt1 complex to the CCNA1 promoter induced methylation and loss of expression, ChIP assays were carried out in E7‐, del CR3‐E7 and vector control‐overexpressing C33a cells. The data showed that E7 induced CCNA1 methylation by forming a complex with Dnmt1 at the CCNA1 promoter, resulting in the subsequent reduction of expression in cancers. It is interesting to further explore the genome‐wide mechanism of E7 oncoprotein‐mediated DNA methylation.     

Comparison of human papillomavirus genotyping and cytology triage,COMPACT Study: Design,methods and baseline results in 14 642 women

Although cytology‐based screening programs have significantly reduced mortality and morbidity from cervical cancer, the global consensus is that primary human papillomavirus (HPV) testing for cervical screening increases detection of high‐grade cervical intraepithelial neoplasia (CIN) and invasive cancer. However, the optimal triage strategy for HPV‐positive women to avoid over‐referral to colposcopy may be setting specific. As Japan requires data that have been generated domestically to modify screening guidelines, we conducted a 3‐year prospective study, COMparison of HPV genotyping And Cytology Triage (COMPACT), to evaluate the potential role of HPV16/18 partial genotyping and cytology for primary HPV screening. In total, 14 642 women aged 20 to 69 years undergoing routine screening at 3 centers in Hokkaido were enrolled. Conventional cytology and HPV testing were carried out. Women with abnormal cytology or HPV16/18 positivity underwent colposcopy. Those with 12 other high‐risk (hr) HPV types underwent repeat cytology after 6 months. Primary study endpoints were detection of high‐grade cervical disease defined as CIN2/CIN3 or greater as determined by consensus pathology. Prevalence of cytological abnormalities was 2.4%. hrHPV, HPV 16, and HPV 18 were detected in 4.6%, 0.9%, and 0.3% of women, respectively. HPV16/18 were detected in all (8/8) invasive cervical cancers and in all (2/2) adenocarcinomas in situ. Both cytological abnormalities and hrHPV positivity declined with increasing age. This is the first Japanese study to investigate the role of partial genotyping and cytology in an HPV‐based screening program. Results should help policy‐makers develop guidelines for future cervical screening programs and management of cervical abnormalities based on HPV genotype.     

Identification of novel immunogenic human leukocyte antigen-A 2402-binding epitopes of human papillomavirus type 16 E7 for immunotherapy against human cervical cancer

BACKGROUND:

A study was undertaken to identify new immunogenic human leukocyte antigen (HLA)‐A*2402‐restricted epitopes from human papillomavirus (HPV) type 16 E7 protein for immunotherapy against cervical cancer.

METHODS:

Synthetic overlapping peptides were screened by measuring the frequency of CD8⁺ cytotoxic T lymphocytes (CTLs) producing intracellular interferon‐γ (IFN‐γ) using flow cytometry and were validated in SiHa cells with a Cr release cytotoxicity assay. In vivo antitumor effects of peptide‐sensitized peripheral blood mononuclear cells (PBMCs) and isolated CD8⁺ CTLs were evaluated using BALB/c nude mice with SiHa cell xenotransplants.

RESULTS:

Among 14 overlapping 15‐amino acid peptides, E7_61‐75(CDSTLRLCVQSTHVD) and E7_67‐81(LCVQSTHVDIRTLED) induced significantly higher IFN‐γ production (P < .05) and showed higher in vitro cytotoxicity against SiHa cells than did cells sensitized with the negative control. To determine the exact HLA‐A*2402‐restricted epitopes, a total of 25 overlapping 9‐ or 10‐amino acid peptides spanning E7_61‐75 and E7_67‐81 were synthesized. E7_61‐69(CDSTLRLCV) and E7_67‐76(LCVQSTHVDI) induced significantly greater IFN‐γ production as well as increased in vitro cytotoxicity against SiHa cells compared with those of other peptides and the negative control (P < .01), and the antitumor effects of these peptide‐sensitized PBMCs were induced by CD8⁺ CTLs. E7_61‐69‐sensitized and E7_67‐76‐sensitized PBMCs and isolated CD8⁺ CTLs showed a much greater suppression of tumor growth in vivo compared with that of control groups treated with PBS (P < .01). The authors also confirmed the synergistic antitumor effect of cisplatin followed by E7_67‐76‐sensitized PBMCs in vivo.

CONCLUSIONS:

E7_61‐69 and E7_67‐76 were identified as novel HPV type 16 E7 epitopes for HLA‐A*2402, which could be used for immunotherapy against cervical cancer. Cancer 2012. © 2011 American Cancer Society.