人乳头瘤病毒疫苗预防宫颈癌的应用

宫颈癌严重危害女性健康,现已明确人乳头瘤病毒(HPV)感染是其主要致病因素。HPV通过机体的细微损伤入侵,HPV E6和E7癌蛋白中的1种或2种持续表达是高危型HPV感染致瘤的关键所在,检测高危型HPV感染及病毒癌蛋白仍不能有效预防宫颈癌。研究者们正着手研制针对HPV的病毒疫苗,从源头预防HPV感染,以期实现宫颈癌的一级预防。目前已有针对HPV16/18型的二价疫苗Cervarix和针对HPV16/18/11/6型的四价疫苗Gardasil的认证上市,预防性HPV疫苗已在全球范围内推广使用并取得显著效果。新一代预防性HPV疫苗在解决疫苗的成本、持久性和广谱免疫问题上取得突破性进展,宫颈癌有望成为人类抗肿瘤史上第一个可以预防的癌症。综述近年HPV的生物学特性、致病机制及预防性HPV疫苗的应用研究与现状。     

宫颈癌HPV预防性疫苗的研究进展

人乳头瘤病毒（HPV）感染是常见的性传播疾病之一。高危人乳头瘤病毒（hrHPV）持续感染是宫颈癌前病变及宫颈癌的主要危险因素。HPV16和HPV18型导致全球大约70%的宫颈癌。宫颈癌普查可减少宫颈癌发生的危险,但不能阻止HPV的感染。很多报道表明,有效的HPV疫苗可以减少HPV相关的宫颈癌、生殖道疣状物的发病率和死亡率。因此,为了有效预防这类疾病,全世界开展了HPV预防性疫苗的研究。目前临床应用的HPV疫苗有HPV 2价疫苗、4价疫苗及9价疫苗,它们可以有效预防相应HPV类型的感染,从而大量减少与此相关的宫颈病变及宫颈癌的发病率和死亡率。本文就HPV、宫颈癌及这3类HPV疫苗的免疫原性、接种剂量的数量和临床应用进行综述。     

HPV疫苗防治宫颈癌的研究进展

宫颈癌是仅次于乳腺癌的女性恶性肿瘤,如何有效防治是全世界研究的热点,HPV感染与宫颈癌有直接关系已经明确,因此,应用HPV预防性疫苗、治疗性疫苗以及兼预防和治疗作用的疫苗来防治宫颈癌成了各国学者的研究方向,并获得了显著的效果。     

HPV疫苗的策略及前景

生殖道人乳头瘤病毒(HPV)感染与生殖道肿瘤密切相关，HPV感染是95％宫颈癌原发因素。HPV疫苗在预防方面前景可观；目前治疗性疫苗的研究集中在修饰的DNA疫苗、多肽疫苗及联合疫苗；而预防性疫苗则主要集中在病毒颗粒的外壳蛋白上，VLP疫苗是最理想的预防性疫苗。预防性疫苗将逐步走向临床。     

香港HPV疫苗接种现状以及对我国内地宫颈癌一级预防的借鉴作用

人乳头瘤病毒(HPV)是引起生殖道感染最常见的病毒之一,高危型HPV持续感染可诱发宫颈癌及癌前病变,预防性接种HPV疫苗是宫颈癌一级预防的重要措施。HPV疫苗早在10年前便于我国香港注册上市,其在香港地区的推广过程中所面临的安全性问题、接受度问题及其所采取的推广方式对于HPV疫苗刚上市的我国内地具有重要的借鉴作用。未来在HPV疫苗的推广过程中,重视HPV疫苗宣传内容,HPV疫苗接种计划,开展宫颈癌筛查联合HPV疫苗接种,以及加快国产疫苗研发及上市是利于其推广的有效手段。     

HPV持续感染与子宫颈上皮内瘤变2级及更严重病变的相关性

宫颈癌严重危害人类的健康,许多研究已充分证明其是由人乳头瘤病毒（HPV）感染引起[1]。由于从HPV感染发展到宫颈癌的进程长达10-20年,其中宫颈上皮内瘤变2级（CIN2）及更严重病变是发展为宫颈癌所经历的癌前阶段。出于伦理,目前已经上市的预防HPV感染的宫颈癌疫苗（二价和四价HPV疫苗）,     

人乳头瘤病毒防治疫苗的应用研究进展

预防性疫苗以人乳头瘤病毒(HPV)晚期结构蛋白L1、L2诱导引发特异性抗体来抵抗HPV感染,治疗性疫苗通过早期HPV基因编码蛋白的抗原表位来产生免疫反应.研发预防性HPV疫苗是防治宫颈癌的一个重要里程碑,其能对抗特定的致癌性HPV型的最初感染,治疗性疫苗对治疗HPV感染相关的宫颈恶性病变带来了契机,但其安全性及远期疗效仍需深入研究.作者探讨了有关HPV感染与宫颈癌流行病学关系、HPV感染与机体免疫反应等妇科肿瘤学的基本问题,着重对HPV防治性疫苗作用机制、生物学特性及其应用现状等作一阐述.     

子宫颈癌疫苗的研究进展

子宫颈癌是妇科常见的恶性肿瘤之一.人乳头状瘤病毒(1auman papiUoma virus,HPV)的持续感染与子宫颈癌的发生密切相关.HPV疫苗在预防和治疗宫颈癌方面备受关注.HPV疫苗能激发机体的细胞和体液免疫应答,有效的预防和控制HPV感染,在预防和治疗宫颈癌方面发挥作用.新型预防性HPV疫苗已在多个国家已经上市;多肽疫苗、蛋白疫苗、病毒载体疫苗、DNA疫苗等治疗性疫苗的研究也有新的进展.现对HPV疫苗在预防和治疗子宫颈癌方面的最新研究进展做一综述.     

子宫颈癌疫苗的研究进展

子宫颈癌是妇科常见的恶性肿瘤之一。人乳头状瘤病毒（human papilloma virus,HPV）的持续感染与子宫颈癌的发生密切相关。HPV疫苗在预防和治疗宫颈癌方面备受关注。HPV疫苗能激发机体的细胞和体液免疫应答,有效的预防和控制HPV感染,在预防和治疗宫颈癌方面发挥作用。新型预防性HPV疫苗已在多个国家已经上市;多肽疫苗、蛋白疫苗、病毒载体疫苗、DNA疫苗等治疗性疫苗的研究也有新的进展。现对HPV疫苗在预防和治疗子宫颈癌方面的最新研究进展做一综述。     

宫颈癌治疗性HPV疫苗的研究进展

人乳头瘤状病毒(HPV)感染与宫颈癌发生密切相关,是宫颈癌发生的最主要危险因素。HPV治疗性疫苗的研发备受关注,目前治疗性疫苗的类型很多,但因其机制较复杂,大多仍处在实验阶段。本文现就宫颈癌治疗性HPV疫苗的最新进展做一综述。     

HPV vaccination: principles, results and future perspectives

Human papillomavirus (HPV) are responsible of an important morbidity and mortality. HPV is a significant source of morbidity and mortality. HPV is the most common sexually transmitted infection: adolescents are at high-risk for HPV acquisition. Biologic and epidemiologic studies have demonstrated that HPV infection is a necessary but non-sufficient cause of cervical cancer and genital warts. The vast majority of cervical cancers contain high-risk HPV type and approximately 70% contain HPV types 16 or 18. HPV types 6 or 11 are responsible for approximately 90% of genital warts. Thus, a vaccine that could prevent. Prophylactic vaccines based on the use of virus-like particles (VLPs) obtained by auto-assembly of L1 are under clinical trials. Two vaccines are currently evaluated: Cervarix (GlaxoSmithKline Biologics), a bivalent vaccine against HPV 16 and 18, and Gardasil (Merck & Co) a quadrivalent vaccine against HPV 16, 18, 6, and 11. Phase I, II and III studies have demonstrated that both vaccines are well tolerated and provide an excellent immunogenicity. With approximately 5-year follow-up, both vaccines have been effective in preventing persistent infection with targeted HPV types and in preventing cervical intraepithelial lesions. The optimal target for vaccination is probably 12-year-old girls.     

Prophylactic HPV vaccines

Infection with human papillomavirus (HPV), in particular HPV 16 and HPV 18, is the main cause of cervical cancer. Two prophylactic vaccines against types 6, 11, 16 and 18 have shown great promise in clinical trials, with recent results demonstrating 100% efficacy against persistent HPV infection and development of CIN up to five years of follow-up. One of these (Gardasil, recently licensed) contains all four HPV types, offering protection against genital warts (types 6 and 11) as well as cervical cancer. The other (Cervarix) contains types 16 and 18, targeting cervical cancer alone. Recent data suggest a degree of cross-protection, against types 31 and 45; this could significantly increase the level of protection afforded by the vaccines. It is envisaged that girls between 11 and 12 will be the target, and this is what has been recommended in the United States. There is still debate about the issue of vaccinating boys. A fundamental issue is the lack of education of both the public and health professionals about HPV. In theory, an HPV vaccine could prevent almost all cervical cancer, eventually removing the need for cervical smears. However, there is at least one whole generation of women for whom the vaccine will come too late, and who will continue to require screening.     

Cervical cancer prevention: the impact of HPV vaccination

Cervical cancer remains a critical public health problem that is second only to breast cancer in overall disease burden for women throughout the world. In spite of the success of cervical cancer screening, Pap cytology screening is yet to be effectively implemented or has failed to reduce cervical cancer rates to an appreciable extent. Screening appears to benefit only a small fraction of women although a much larger percentage endures the inconvenience of the Pap test in order to avoid cervical cancer. The establishment of Human Papillomavirus (HPV) infection as the necessary cause of cervical precancers and cancers provides a tremendous opportunity for cervical cancer prevention through vaccination. HPV 16 and 18 which cause 70% of cervical cancers worldwide. Thus a prophylactic vaccine to prevent HPV related precancerous lesions and cancers would save lives, reduce the need for costly medical procedures and provide both women and communities throughout the world with substantial benefits. Based on the induction of neutralizing antibodies by non infectious Virus Like Particles (VLP) of L1 capside protein, prophylactic HPV vaccines have consistently induced high titter of neutralizing antibodies with minimal side effects and induce more than 90% protection from persistent HPV 16-18 infection and HPV 16 and 18 associated high-grade Cervical Intraepithelial Neoplasia (CIN) in proof of concept efficacy trials. HPV 16-18 vaccination will prevent HPV16-18 incident infection, and subsequently decrease in 90% the frequency of abnormal Pap attributable to these types and in about 50% overall abnormal Pap. HPV vaccination will reduce the number of women who require colposcopy, biopsy and cervical treatment for precancerous cervical lesions. The level of protection from death due to cervical cancer could exceed 95%. Three large phases prophylactic HPV VLP trials are now in progress and will form the basis for licensing of candidate vaccines in 2006. HPV vaccination targeting young female adolescents, aged 11 to 16 years, with a catch-up of those aged 17-25 years, would be a strategy to be addressed. Cervical cancer screening strategies, that will be cost-effective for the proper surveillance of women protected by HPV vaccination, are under analysis.     

New advances in vaccine technology and improved cervical cancer prevention

Cervical cancer, which is caused by oncogenic types of the human papillomavirus (HPV), is the second most common cancer in women, responsible for 274,000 deaths worldwide in 2002. Approximately 70% of all cervical cancers are caused by the two most common oncogenic HPV types, HPV-16 and HPV-18; another 10% are caused by the next most common types, HPV-45 and HPV-31. Therefore, vaccines designed to prevent infection with oncogenic HPV types have the potential to decrease morbidity and mortality associated with cervical cancer and precancerous lesions. Vaccinology research recently has developed tools that may be used to improve the safety and efficacy of vaccines, and several of these tools have been used in the development of HPV vaccines. These advances include new insight into antigen selection, inclusion of adjuvants designed to enhance the immunogenicity of vaccines, and investigation into alternative routes of administration. Clinical studies of HPV vaccines that take advantage of these technological advances have reported excellent safety, immunogenicity, and efficacy results for prevention of HPV infection and incidence of associated cytopathologic abnormalities.     

Human papillomavirus prophylactic vaccines: stakes and perspectives

Human Papillomavirus (HPV) infection is established as the necessary cause of cervical precancers and cancers. To date, more than 120 genotypes are known, but only high risk oncogen genotypes could induce a cancer. HPV 16 and 18 are implied in nearly 70% of cervical cancer around the world. Although some persistent HPV infections progress to cervical cancer, host immunity is generally able to clear most HPV infections providing an opportunity for cervical cancer prevention through vaccination. Candidate prophylactic vaccines based on papillomavirus L1 virus-like particles (VLPs) are currently on human clinical trials: one targeting cervical cancer with a bivalent VLP L1 vaccine containing the two genotypes most frequently involved in cervical cancer (type 16 and 18) and the other, protecting against warts as well as cervical cancer, with a quadrivalent HPV VLP L1 vaccine containing genotypes 6, 11, 16 and 18. The first clinical trials revealed the satisfactory tolerance and excellent immunogenicity of these vaccines inducing high serum antibody titers with minimal side effects. After more than three years, both clinical trials on women 15 to 25 years old have shown that vaccines are able to type specifically protect against nearly 90% of infection and all cervical intra-epithelial neoplasia. The vaccinal strategy defined to date targets preadolescents and adolescent young females (11-13 years) before the first sexual course but some questions are still not resolved concerning the prescriber, the actors of the vaccination and the duration of the protection. Nevertheless cervical cancer screening should be carried on for many years, even if a large vaccinal strategy is decided. Such a vaccine would save lives and reduce the need for costly medical procedures and the psychological stress induced by this cancer.     

人乳头瘤病毒16/18型与宫颈癌

人乳头瘤病毒（HPV）16/18型和宫颈癌的关系密切,在宫颈癌发生发展中起重要作用。HPV16最易导致宫颈鳞癌,HPV18最易导致宫颈腺癌。HPV16/18致癌机制主要是通过病毒基因组中致癌蛋白E6,E7与抑癌基因p53和pRb结合,E6抑制p53的活性,E7灭活Rb基因的活性,致肿瘤发生。常用的HPV检测方法有原位杂交法（ISH）、第二代杂交捕获试验（HCⅡ）、聚合酶链反应（PCR）等。针对HPV16/18的预防和治疗性疫苗成为研究热点。综述HPV16/18型和宫颈癌关系研究进展。     

Human papillomavirus vaccines and adolescents

PURPOSE OF REVIEW: This review will describe human papillomavirus (HPV) vaccines in development, summarize data regarding safety and efficacy of these vaccines, and discuss key issues related to HPV vaccine implementation. RECENT FINDINGS: Evidence from epidemiologic and genetic studies has confirmed that HPV infection is a necessary cause of cervical cancer and contributes to the development of other cancers. HPV infection also may cause nonmalignant conditions such as external genital warts and recurrent respiratory papillomatosis. Over the past decade, several vaccines that target common HPV types have entered clinical trials. These vaccines are classified as prophylactic or therapeutic. The goal of prophylactic vaccines is to prevent primary or persistent HPV infections, and thus prevent cervical cancer and/or genital warts. Recent evidence indicates that prophylactic vaccines are well tolerated, highly immunogenic and effective in preventing persistent HPV infection and cervical intraepithelial neoplasia (CIN). Questions remain, however, concerning vaccine efficacy against HPV-related diseases other than cervical cancer, the duration of protection, vaccine acceptability and feasibility of vaccine delivery in the developing world. The goal of therapeutic vaccines is to prevent progression of HPV infection, induce regression of CIN or condylomata, or eradicate residual cervical cancer. Although therapeutic vaccines appear to induce both humoral and cell-mediated immunity, they have not consistently demonstrated clinical efficacy. SUMMARY: HPV vaccines in development have the potential to reduce the substantial morbidity and mortality associated with cervical cancer and other HPV-associated diseases. Large-scale efficacy studies that are planned or underway will provide additional information about vaccine tolerance and efficacy.     

Vacunas contra el virus del papiloma humano

Persistent infection by human papilloma virus (HPV) is considered to be the main cause of cervical cancer and other ano-genital cancers. Of more than 30 genotypes able to infect the anogenital tract, it is estimated that, worldwide, HPV 16 and 18 cause 70% of cervical cancers and that HPV 6 and 11 cause more than 90% of genital warts. In the last few years, the morbidity and mortality and health costs associated with cervical cancer and its precursor lesions have stimulated intense research activity to achieve primary prevention of this disease through prophylactic vaccines.     

Prophylactic and therapeutic vaccination against human papillomavirus

Human papillomavirus is a necessary cause for the development of cervical cancer. Cervical cancer is attributed to 15 high-risk oncogenic HPV among the 120 genotypes present in human. The infection affects about 3 out of 4 women and is often transient thanks to immunological modulators leading to viral clearance. This characteristic made it possible to develop vaccines. Prophylactic vaccines are made of virus-like particles L1, non infectious, well tolerated and highly immunogenic. They prevent from viral infection by producing antibodies, which are secreted throughout the genital mucosa (humoral immunity). High-risk oncogenic HPV-16 and 18, responsible for 70% of cervical cancer, are included in Gardasil and Cervarix. Both vaccines prevent from HPV infection and related cervical and perineal lesions in more than 90% of the cases. Therapeutic vaccines are made of epitope peptides, recombinant proteins and bacteria, plasmid DNA or dendritic cells. All sensitize immunocompetent cells (cellular immunity). Ineffective in cervical cancers, they induce the regression of cervical dysplasia in about 50% of the cases. They are still under research and development, in opposition to prophylactic vaccines, which are available.