Changes in type‐specific human papillomavirus load predict progression to cervical cancer

Persistent high-risk human papillomavirus (HPV) infection is strongly associated with the development of high-grade cervical intraepithelial neoplasia or cancer (CIN3+). However, HPV infection is common and usually transient. Viral load measured at a single time-point is a poor predictor of the natural history of HPV infection. The profile of viral load evolution over time could distinguish HPV infections with carcinogenic potential from infections that regress. A case-cohort natural history study was set-up using a Belgian laboratory database processing more than 100,000 liquid cytology specimens annually. All cytology leftovers were submitted to real-time PCR testing identifying E6/E7 genes of 17 HPV types, with viral load expressed as HPV copies/cell. Samples from untreated women who developed CIN3+ (n = 138) and women with transient HPV infection (n = 601) who contributed at least three viral load measurements were studied. Only single-type HPV infections were selected. The changes in viral load over time were assessed by the linear regression slope for the productive and/or clearing phase of infection in women developing CIN3+ and women with transient infection respectively. Transient HPV infections generated similar increasing (0.21 copies/cell/day) and decreasing (−0.28 copies/cell/day) viral load slopes. In HPV infections leading to CIN3+, the viral load increased almost linearly with a slope of 0.0028 copies/cell/day. Difference in slopes between transient infections and infections leading to CIN3+ was highly significant (P < .0001). Serial type-specific viral load measurements predict the natural history of HPV infections and could be used to triage women in HPV-based cervical cancer screening.     

Human papillomavirus and tar hypothesis for squamous cell cervical cancer

Cervical cancer is the second most common life-threatening cancer among women worldwide, with incidence rates ranging from 4.8 per 100,000 in the Middle East to 44.3 per 100,000 in East Africa. Human papillomavirus (HPV) infection, especially HPV-16 and HPV-18, plays a major role in the etiology of cervical cancer, but HPV alone is not sufficient to induce cancer. We propose that squamous cell cervical cancer is caused by an interaction of oncogenic viruses and cervical tar exposures. Cervical tar exposures occur from cigarette smoking, use of tar-based vaginal douche products (TBD), and long years of inhaling smoke from wood- and coal-burning stoves in poorly ventilated kitchens.     

人乳头瘤病毒感染与宫颈癌的研究进展

人乳头瘤病毒(Human Papillomavirus HPV)感染是导致性传播疾病的常见原因,上世纪八十年代初,首次报道生殖器HPV感染与宫颈癌之间的联系,认为HPV感染是95%以上宫颈癌变的高危因素。随着分子生物学技术的发展,对HPV致癌机制的研究不断深入,取得大量有价值的成果,现就HPV的致癌途径与协同因素探讨宫颈癌的发病机制以及对HPV检测方法等方面的研究进行综述。     

一氧化氮、人乳头瘤病毒和宫颈癌之间相互关系的研究进展

人乳头瘤病毒感染是宫颈癌发生的重要始动原因,从HPV感染到宫颈癌发生,需要许多共刺激因子的参与。这些共刺激因子均可引起宫颈局部一氧化氮浓度的增高。而一氧化氮既可影响HPV的转录和翻译,又在肿瘤发生过程中具有重要调节作用。深入研究一氧化氮、人乳头瘤病毒感染及宫颈癌之间的关系,可为宫颈癌的防治提供新的重要理论基础和药物研制实验平台,通过使用一氧化氮合酶抑制剂降低宫颈局部NO浓度将为全面有效防治宫颈癌带来新的希望。     

Strategies against human papillomavirus infection and cervical cancer

Papillomaviruses infect a wide variety of animals, including humans. The human papillomavirus (HPV), in particular, is one of the most common causes of sexually transmitted disease. More than 200 types of HPV have been identified by DNA sequence data, and 85 HPV genotypes have been well characterized to date. HPV can infect the basal epithelial cells of the skin or inner tissue linings, and are, accordingly, categorized as either cutaneous or mucosal type. HPV is associated with a panoply of clinical conditions, ranging from innocuous lesions to cervical cancer. In the early 1980s, studies first reported a link between cervical cancer and genital HPV infection. Genital HPV infections are now recognized to be a major risk factor in at least 95% of cervical cancers. 30 different HPV genotypes have been identified as causative of sexually transmitted diseases, most of which induce lesions in the cervix, vagina, vulva, penis, and anus, as the result of sexual contact. There is also direct evidence demonstrating that at least four of these genotypes are prerequisite factors in cervical cancer. The main aim of this review was to evaluate the current literature regarding the pathovirology, diagnostics, vaccines, therapy, risk groups, and further therapeutic directions for HPV infections. In addition, we reviewed the current status of HPV infections in South Korean women, as evidenced by our data.     

Characterization and high‐yield production of non‐N‐glycosylated recombinant human BCMA‐Fc in Pichia pastoris

B‐cell maturation antigen (BCMA) fused at the C‐terminus to the Fc portion of human IgG1 (BCMA‐Fc) blocks B‐cell activating factor (BAFF) and proliferation‐inducing ligand (APRIL)‐mediated B‐cell activation, leading to immune disorders. The fusion protein has been cloned and produced by several engineering cell lines. To reduce cost and enhance production, we attempted to express recombinant human BCMA‐Fc (rhBCMA‐Fc) in Pichia pastoris under the control of the AOX1 methanol‐inducible promoter. To produce the target protein with uniform molecular weight and reduced immunogenicity, we mutated two predicted N‐linked glycosylation sites. The secretory yield was improved by codon optimization of the target gene sequence. After fed‐batch fermentation under optimized conditions, the highest yield (207 mg/L) of rhBCMA‐Fc was obtained with high productivity (3.45 mg/L/h). The purified functional rhBCMA‐Fc possessed high‐binding affinity to APRIL and dose‐dependent inhibition of APRIL‐induced proliferative activity in vitro through three‐step purification. Thus, this yeast‐derived expression method could be a low‐cost and effective alternative to the production of rhBCMA‐Fc in mammalian cell lines.     

Prevalence of human papillomavirus genotypes in cervical cancer and precursor lesions

There are no data obtained in biopsy material on the prevalence of human papillomavirus (HPV) and HPV genotypes in Croatian women with cervical carcinoma and precursor lesions. Therefore, the prevalence of HPVand HPVgenotypes was investigated in archival material of cervical carcinoma and precursor lesions kept at Department of Pathology, School of Medicine, University of Rijeka. DNA was isolated from formalin fixed, paraffin embedded tissue, histologically classified as cervical intraepithelial neoplasia (CIN) III (n =43), squamous cell carcinoma (SCC) (n =54) and adenocarcinoma (ADC) (n =40). HPV testing was performed bypolimerase chain reaction (PCR) using generic and genotype specific primers. The prevalence of HPV DNA was 93.02%, 92.59%, and 92.5% in CIN III, SCC and ADC, respectively. In CIN III and SCC, HPV-16 was the most common high-risk genotype, identified in 65% and 52%, followed by HPV-18 in 22.5% and 28% of cases, respectively. HPV-18 showed a statistically significant prevalence in ADC (67.6%) as compared with SCC (chi(2)=9.924; p_ 0.01). Study results revealed a high prevalence of HPV-DNA in examined cervical lesions (>90%). HPV-16 predominated in SCC and HPV-18 in ADC. Single infection was more frequently present than multiple infections in all three histological groups.     

Association of human papillomavirus and Chlamydia infections with incidence cervical neoplasia

Incidence cervical neoplasia is defined as disease that becomes manifest during a given period of observation. Association with preceding genital infections having characteristic cytologic findings would seem to be more likely for incidence than for prevalence cases since the usual long latency period of carcinoma in situ (CIS) could allow resolution of infectious processes. For this reason, it was elected to examine the preceding Papanicolaou smears from patients with tissue-confirmed incidence CIS or invasive epidermoid carcinoma. There were 67 women with biopsy-proven CIS or invasive carcinoma of the uterine cervix identified in the files of the University of New Mexico Cytopathology Laboratory from 1966 to 1982 who had two initial negative smears as well as smears at intervals of three years or less. All cytologic smears prior to tissue diagnosis were rescreened for confirmation of cytologic atypia or its absence as well as for morphologic evidence of human papillomavirus (HPV) or chlamydial infections. Control cases matched for age, gravidity, ethnicity and number of smears were reviewed in an identical manner. Koilocytes indicative of HPV infection were found in 17 index cases (25%) and 5 controls (7%) (p = 0.005). Chlamydial infections were identified in 18 index cases (27%) and in 4 controls (6%) (p = 0.001). The times required for conversion from smear negativity to malignancy were determined for each incidence case. The results showed great variability but suggest that the progression to malignancy is not hastened in women with antecedent HPV or chlamydial infections. Our results indicate that the presence of koilocytes and/or chlamydial inclusions in cervical smears serves to identify a group of women with a significantly increased risk of developing cervical carcinoma, even in the absence of concurrent dysplasia.     

Heterografts of human cervical cancer. Characterization of papillomavirus genomes

Three new human cervical carcinoma xenografts was established from clinical tumor specimens of patients with I-II stages of disease. Growth characteristics of models are writing. Xenografts designated CC 9, 24 and 25 contain integrated DNA HPV, complemented DNA HPV-16. DNA CC 5 contain neither DNA HPV-16, nor DNA HPV-18.     

HPV检测早期筛查宫颈癌的临床意义——附妇科门诊2761例宫颈拭子HPV分析

目的探讨女性HPV DNA检测在宫颈癌防治方面的意义。方法应用DNA杂交技术对2 761例妇科门诊就诊者基因分型检测。结果 2 761例样本中,HPV感染有768例,阳性率27.82%,HPV感染人次972人次。检测高危型HPV（16,18,31,33,35,39,45,51,52,56,58,59,68）813人次,占感染总人次的83.64%;检出低危型HPV（6,11,42,43,44）73人次,占感染总人次7.51%;中国人群常见型HPV（53,66,CP8304）86人次,占感染总人次的8.85%。165例样本中包含了25种亚型的感染。结论 DNA杂交技术检测HPV基因分型,可一次检测多种亚型,有利于对HPV多重感染的诊断和宫颈癌的防治,可作为宫颈癌筛查的手段。     

AgNOR technique could be useful for differential diagnosis of squamous carcinomatous cells and atypical cells related to human papillomavirus in cervical smears

The human papillomavirus (HPV)-associated effect can mimic invasive squamous cell carcinoma. Measurements of the argyrophilic nucleolar organizer region (AgNOR) area of cells from smears with HPV infection of the cervix with marked atypia were carried out to differentiate this pathology from keratinizing carcinomas. After destaining, the smears were incubated in the dark for 25 min with a mixture of silver nitrate and gelatin in formic acid. After washing with deionized water and sodium thiosulfate, the slides were dehydrated and mounted with Canada balsam. The average AgNOR area was determined by image cytometry using the immersion oil objective and selecting 100 cells in each smear. Twenty-three patients with a mean AgNOR area of 1.32 µm² among their samples showed normal colposcopies and cervical smears after 18 months. In four patients, whose samples were diagnosed as atypical squamous cells of undetermined significance with viral atypia, the average AgNOR area was 7.70 µm²; biopsies showed keratinizing squamous carcinomas in three of these cases and moderately differentiated squamous carcinoma in one of them. We propose a cutoff of 2.2 µm² for the AgNOR area of cells from smears with HPV infection of the cervix with marked atypia to differentiate this group from keratinizing carcinomas.