J Mass Spectrom 2006 May 22; (Read article online)

Shin HS, Ahn HS

A gas chromatography-mass spectrometry method was developed for the determination of the propylene oxide (PO)-hemoglobin adduct. The adduct was identified as hydroxy propyl valine (HPV), and released from globin by the modified Edman degradation and extracted with ethyl ether. HPV and deuterated HPV (d(6)-HPV) were synthesized for identification and quality control. d(6)-HPV was used as an internal reference standard. The dried extract was completely derivatized with N-methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA). The method detection limit (MDL) of the assay was 10 pmole/g for HPV, based on assayed hemoglobin of 0.1 g. The method was applied to the determination of the PO-hemoglobin adduct formed in young female Sprague-Dawley rats after treatment for 4 and 5 weeks with 5 and 10 mM PO via drinking water. HPV was detected by the proposed procedure. After 4 weeks, the concentration of HPV was 6.75 nmole/g hemoglobin during treatment with 5 mM, and 80.26 nmole/g hemoglobin during treatment with 10 mM. The adduct level in 5 weeks increased up to about 51.47 nmole/g during treatment with 5 mM PO in the drinking water and up to about 120.27 nmole/g during treatment with 10 mM PO. This method was also applied to determine the concentrations of HPV in the blood of 20 persons living near the Ulsan petroleum industrial complex in Korea. As a result, HPV-hemoglobin adduct was detected in the concentration range 0-1100 pmol/g in the human blood samples. Copyright (c) 2006 John Wiley & Sons, Ltd.

Pharmacology 2006 May 23; 77(3): 122-129 (Read article online)

Uzun O, Demiryurek AT

The aim of this study was to investigate the effect of hypoxia on and the role of nitric oxide (NO) and cyclooxgenase inhibition in hypoxia-induced vasoconstriction in sheep isolated pulmonary veins. We used the potent pulmonary vasoconstrictor U46619, a thromboxane analog, as a precontractile agent. Our results showed that hypoxia caused a vasoconstriction both under resting tone and in U46619 (10(-6) mol/l) precontracted pulmonary veins. In the presence of the nonselective NO synthase inhibitior Nomega-nitro-L-arginine methyl ester (L-NAME; 3 x 10(-5) mol/l), the hypoxic pulmonary vasoconstriction (HPV) was significantly increased in veins under resting force. However, there was a decrease in HPV in pulmonary veins precontracted with U46619 in the presence of L-NAME. Moreover, L-NAME markedly augmented the U46619-induced pulmonary contractions under normoxic conditions. Cyclooxygenase inhibition with indomethacin (10(-5) mol/l) significantly reduced the HPV both under resting tone and in precontracted veins. Indomethacin also significantly decreased the U46619-induced pulmonary contractions prior to the induction of hypoxia. Our findings suggest that NO and prostaglandins can act as a modulators of the hypoxic vasoconstriction in isolated pulmonary veins. Copyright (c) 2006 S. Karger AG, Basel.

Biochemistry 2006 May 30; 45(21): 6551-6560 (Read article online)

Cicero DO, Nadra AD, Eliseo T, Dellarole M, Paci M, de Prat-Gay G

Strain 16 of the human papillomavirus is responsible for the largest number of cases of cervical cancers linked to this virus, and the E2 protein is the transcriptional regulator of all viral genes. We present the first structure for the DNA binding domain of HPV16 E2 bound to DNA, and in particular, to a natural cognate sequence. The NMR structure of the protein backbone reveals that the overall conformation remains virtually unchanged, and chemical shift analysis of the protein bound to a shorter DNA duplex uncovered a contact out of the minimal E2 DNA binding site, made by lysine 349. This contact was confirmed by titration calorimetry and mutagenesis, with a contribution of 1.0 kcal mol(-)(1) to binding energy. HPV16 E2 has the highest DNA binding affinity and exerts a strict transcriptional control, translated into the repression of the E6 and E7 oncogenes. These novel features provide the structural and thermodynamic basis for this tight transcriptional control, the loss of which correlates with carcinogenesis.

J Biol Chem 2006 May 22; (Read article online)

Tomai E, Butz K, Lohrey C, von Weizsäcker F, Zentgraf H, Hoppe-Seyler F

Peptide aptamers (PAs) can be employed to block the intracellular function of target proteins. Little is known about the mechanism of PA-mediated protein inhibition. Here, we generated PAs which specifically bound to the duck hepatitis B virus (DHBV) core protein. Among them, PA34 strongly blocked DHBV replication by inhibiting viral capsid formation. We found that PA34 led to a dramatic intracellular redistribution of its target protein into perinuclear inclusion bodies, which exhibit the typical characteristics of aggresomes. As a result, the core protein is efficiently removed from the viral life cycle. Corresponding findings were obtained for bioactive PAs which bind to the hepatitis B virus (HBV) core protein or to the human papillomavirus-16 (HPV16) E6 protein, respectively. The observation that PAs induce the specific sequestration of bound proteins into aggresomes defines a novel mechanism as to how this new class of intracellular inhibitors blocks the function of their target proteins.

Cancer Cell Int 2006 May 22; 6(1): 14 (Read article online)

Kingsley K, Johnson D, O'malley S

ABSTRACT: BACKGROUND: Human papillomavirus has been implicated in virtually all cervical cancers and is believed to be the primary etiological factor that transforms cervical epithelia. The presence of HPV in oral cancers suggests that HPV may play a similar role in transforming the oral epithelia. The prevalence of HPV in oral cancers is highly variable, however, presenting problematic issues regarding the etiology of oral cancers, which must be investigated more thoroughly. Past analyses of HPV in cancers of the oral cavity have largely been confined to retrospective studies of cancer patients. The purpose of this study was to examine the potential for HPV16 infection to alter the proliferative phenotype of oral squamous cell carcinoma in vitro. RESULTS: This study found that the oral squamous cell carcinoma cell line, CAL27, transfected with HPV16, exhibited significantly increased proliferation, compared with non-transfected CAL27. The increased proliferation was observed under low density conditions, even in the absence of serum. Moreover, these effects were specific to proliferation, adhesion, and morphology, while cell viability was not affected. CONCLUSION: This study represents one of the first investigations of the effects of HPV16 infection on the proliferation, adhesion, and morphology of an oral squamous cell carcinoma cell line in vitro. The finding that HPV16 has the ability to measurably alter adhesion and proliferative potential is significant, indicating that HPV may have multiple influences on precancerous and cancerous lesions and should be explored as a risk factor and mediator of cancer phenotypes. These measurements and observations will be of benefit to researchers interested in elucidating the mechanisms of oral cancer transformation and the factors governing carcinogenesis and progression.

Gynecol Obstet Invest 2006 May 24; 62(3): 173-180 (Read article online)

Kliucinskas M, Nadisauskiene RJ, Minkauskiene M

Aims: To investigate the prevalence, persistence and risk factors of high oncogenic risk human papillomavirus (HPV) among urban and rural women of reproductive age coming to consult a gynaecologist. Methods: A prospective cohort study in urban (Kaunas) and rural (Marijampole) regions of Lithuania. The data were collected in 8 healthcare institutions from women seeking consultation of gynaecologists using a questionnaire for finding out demographic, social, behavioural and biomedical factors. HPV DNA was determined by molecular hybridization method (hybrid capture version II) determining HPV of high oncogenic risk. Result: 1,120 women participated in the study. The prevalence of high-risk HPV among the studied women was 25.1%. It was higher among the urban women than among the rural women. The prevalence of high-risk HPV was increased if the subjects had 2 or more sexual partners during the last 12 months (OR 2.81; 95% CI 1.83-4.32), were 19 years of age or younger (OR 2.68; 95% CI 1.47-4.91), were smoking (OR 1.81; 95% CI 1.16-2.81), and had secondary or lower education level (OR 1.43; 95% CI 1.01-2.04). This infection was obviously associated with high- and low-grade squamous intraepithelial changes of the cervix (OR 1.66, 95% CI = 1.08-2.53). Conclusion: The incidence rate for cervical cancer in Lithuania is one of the highest in comparison with other European countries. HPV infection was also particularly common in the studied population. About one-fourth of the women were infected with high-risk HPV infection. Young and less educated women were found to be the group that was most exposed to HPV, and therefore public health interventions and education seem to be essential in programs aimed at reducing the incidence of cervical cancer. Copyright (c) 2006 S. Karger AG, Basel.

Eur J Obstet Gynecol Reprod Biol 2006 May 17; (Read article online)

Ait Menguellet S, Collinet P, Debarge VH, Nayama M, Vinatier D, Leroy JL

OBJECTIVES: To report management and outcome of multicentric lesions of the lower genital tract. To define risk factors of recurrence. STUDY DESIGN: Retrospective review of multicentric dysplasias treated in our colposcopic clinic between 1996 and 2003. Multicentric dysplasias included CIN with VAIN and/or VIN. After primary treatment, follow-up was colposcopic, cytologic and virologic. RESULTS: Forty-four patients presented multicentric lesions out of 998 patients referred for CIN (4.4%). The average age was 36.8 years. Immunologic disorders were present in 20.4%. Ninety-one percent had cervicovaginal or cervicovulvar lesions, only 9% had three sites of genital dysplasia. 53.3% of lesions were concomitant. 79.5% of CIN were high grade, 62.5% of VAIN low grade and 62.5% of VIN high grade. Therapeutic modalities were as follows: conization for CIN (70.4%), CO2 laser for VAIN (33.3%) and surgery for VIN (41.7%). Forty patients were followed and had at least one post-treatment cytologic control; 55% of them had residual disease. Out of the 23 patients with at least two negative controls after treatment, 43.5% presented recurrence. Risk of recurrence was not statistically bound to such parameters as tabagism, immunologic disorder, high grade lesions, non-surgical treatment, and persistence of HPV infection after treatment. CONCLUSION: Multicentric dysplasias are associated with high rate of residual lesion and recurrence. Management of these lesions require long term follow-up.

J Clin Pathol 2006 May 19; (Read article online)

van Seters M, Ten Kate FJ, van Beurden M, Verheijen RH, Meijer CJ, Burger MP, Helmerhorst TJ

BACKGROUND: Differentiated vulvar intraepithelial neoplasia (VIN) is considered the presumable precursor of invasive squamous cell carcinoma (SCC) of the vulva. It is commonly assumed that differentiated VIN is related to lichen sclerosus (LS). However, argumentation for this is limited to a small number of studies describing epithelial alterations adjacent to vulvar SCC. AIM: To study the histology and human papillomavirus (HPV) status in patients with a history of both LS and VIN without coexistent SCC. METHODS: Original biopsies and surgical specimens of patients retrieved from the pathology files were revised for the presence of LS, VIN and (early) invasive SCC, specifically focused on the two different types of VIN: differentiated and undifferentiated. Thereafter, VIN-lesions were tested for the presence of HPV DNA. RESULTS: Twenty-seven patients fulfilled the criteria for LS and VIN without SCC. In all 27 patients we found LS related to undifferentiated VIN. Grading resulted in VIN 1 (n=10), VIN 2 (n=11) and VIN 3 (n=6). Additionally, VIN lesions from 26 patients could be tested for the presence of HPV DNA. In eight of them (31%) HPV DNA was present, predominantly type 16. Seven of these eight patients had VIN 2 or 3. During follow-up three patients progressed to (early) invasive carcinoma. In two of these patients, differentiated VIN was observed overlying early invasive SCC. CONCLUSIONS: VIN related to LS without coexisting SCC is likely to be undifferentiated, unlike what was previously thought. HPV DNA was demonstrated in 31% and strongly related to high-grade VIN.

Vaccine 2006 May 2; (Read article online)

Li Y, Subjeck J, Yang G, Repasky E, Wang XY

In this study, we explored the protective anti-tumor potency of mouse (self) Hsp70 or Hsp110-based DNA vaccination approach targeting a tumor-associated antigen, human papilloma virus (HPV) type 16 E7 protein. Linkage of E7 to the N-terminus of the mouse Hsp70 not only elicits an E7-specific cytotoxic T cell (CTL) response, but also protects mice against challenge with E7 expressing tumors. CD8(+) T-cells are crucial in both priming and effector phases for the induction of tumor immunity, whereas CD4(+) T-cells and NK cells do not appear to play a major role. Furthermore, the ATP-binding domain deletion mutant Hsp70(382-641), when fused to E7, was immunologically effective, suggesting that the peptide-binding region, not the ATPase domain of Hsp70, is required for the vaccine activity of the E7-Hsp70 DNA. This study demonstrates that autologous Hsp70 is highly potent in enhancing antigen-specific immune responses. Functional domain mapping and orientation of the E7 and Hsp70 in the fusion gene may have clinical implications for the design and optimization of Hsp70-based DNA vaccines.

J Clin Pathol 2006 May 19; (Read article online)

Borbély AA, Murvai M, Szarka K, Kónya J, Gergely L, Hernádi Z, Veress G

AIMS: Survivin, a novel member of the inhibitor of apoptosis (IAP) family, plays an important role in cell cycle regulation. A common polymorphism at the survivin gene promoter (G/C at nt -31) was shown to be correlated with survivin gene expression in cancer cell lines. Our aim was to investigate whether this polymorphism could be involved in the development of HPV associated cervical carcinoma. METHODS: Survivin promoter polymorphism was detected in patients with cervical cancer, patients with equivocal cytologic atypia and in a control population using PCR-RFLP (restriction fragment length polymorphism) and PCR-SSCP (single strand conformation polymorphism) analysis. HPV was typed in cervical cancer and cytologic atypia patients using PCR-RFLP. RESULTS: We could not find any statistically significant differences in the genotype distributions of the survivin promoter variants among our study groups. CONCLUSIONS: Our findings suggest that the survivin promoter polymorphism at nt -31 may not represent an increased risk for the development of cervical cancer, at least in the population studied here.

Arch Dermatol Res 2006 Jul; 298(2): 64-72 (Read article online)

Zhao KJ, Cheng H, Zhu KJ, Xu Y, Chen ML, Zhang X, Song T, Ye J, Wang Q, Chen DF

Calreticulin (CRT) has been reported to have an effect of upregulating MHC class I presentation as well as inhibiting angiogenesis in vitro and in vivo. Combination of dual mechanisms of enhanced immunogenicity of human papillomavirus (HPV) 6bE7 antigen and antiangiogenesis may be introduced in the strategy of vaccines against condyloma acuminatum (CA) resulting from HPV infection. Therefore, we constructed DNA vaccines by employing different lengths of CRT chimerically linked to a model antigen HPV6bE7 and investigated the immunological and antiangiogenic effects of these vaccines in a B16 melanoma model that express HPV6bE7 antigen. Our results showed that vaccination with CRT180/HPV6bE7 or CRT120/HPV6bE7 enhanced the presence of CD8(+) T cells and TCRgammadelta T cells in vivo, increased the specific lysis activity against E7-expressing cells and secretion levels of IL-2 and IFN-gamma by activating T cells in vitro significantly. Moreover, recombined CRT180 or CRT120 with HPV6bE7 vaccines could elicit a more efficient E7-specific immune response than HPV6bE7 alone. The similarity of immunological enhancement of CRT180/HPV6bE7 and CRT120/HPV6bE7 implies that the immunologically active region mainly exist in fragment 1-120 aa. Furthermore, CRT180/HPV6bE7 and CRT180 displayed remarkable superiority over CRT120/HPV6bE7 in vivo angiogenesis assay, suggesting that the antiangiogenic activity of CRT resides in a domain between aa 120 and 180. Vaccination with CRT180/HPV6bE7 generated the best protective effect of delaying tumor formation and reduction of tumor size in tumor growth inhibition experiment among all DNA constructs. Therefore, CRT180/HPV6bE7 vaccine may enhance the immunological response to HPV6bE7 and inhibit angiogenesis. This construct may be useful in preventing HPV-associated dermatosis and may be developed as a promising strategy to control CA.

J Clin Immunol 2006 May 16; (Read article online)

Scott ME, Ma Y, Farhat S, Shiboski S, Moscicki AB

Measurements of mucosal immune parameters in the uterine cervix are potentially influenced by numerous factors, including infections, endogenous and exogenous hormones, semen, and nicotine and its metabolites in cervical mucus. The objective of this study was to examine correlates of immunoregulatory cytokine mRNA expression in cervical cytology samples in a cross-sectional design. Samples, collected at study entry by cervical cytology brush from 368 women aged 13-21 enrolled in a longitudinal study of the natural history of human papillomavirus (HPV) infection, were tested by quantitative RT-PCR for expression of IFN-gamma, IL-4, IL-10, and IL-12. In a multivariate analysis, elevated levels of IFN-gamma, IL-10, and IL-12 were significantly (p < 0.05) associated with several variables, including current C. trachomatis infection, recent intercourse, and current oral contraceptive pill use. Suppressed IL-4 and IL-10 levels were associated with cigarette smoking within the last 24 h. Time since last menstrual period did not affect any of the cytokines; in a substudy of weekly cytokine variability, however, IL-10 showed a non-significant trend toward higher levels around the time of menstruation.

Cancer Epidemiol Biomarkers Prev 2006 May; 15(5): 908-14 (Read article online)

Kreimer AR, Guido RS, Solomon D, Schiffman M, Wacholder S, Jeronimo J, Wheeler CM, Castle PE

BACKGROUND: Loop electrosurgical excision procedure (LEEP) is the predominant treatment for cervical intraepithelial neoplasia grade 2 or 3 (CIN2+) in the United States, yet following treatment approximately 10% of women are diagnosed again with CIN2+, necessitating close follow-up of such patients. METHODS: Surveillance strategies using cytology and/or human papillomavirus (HPV) testing were compared among women who underwent LEEP (n = 610) in the Atypical Squamous Cells of Undetermined Significance (ASCUS) Low-Grade Squamous Intraepithelial Lesion (LSIL) Triage Study. Cervical specimens, collected at 6-month visits for 2 years, were used for cytology, Hybrid Capture 2 (HC2) detection of carcinogenic HPVs, and PCR for genotyping of carcinogenic and noncarcinogenic HPV types. At exit, women had colposcopy for safety and disease ascertainment. RESULTS: At the visit post-LEEP (median time: 4.5 months after LEEP), 36.9% [95% confidence interval (95% CI), 32.7-41.1%] of women were positive for carcinogenic HPV by PCR and 33.7% (95% CI, 29.7-37.9) had ASCUS or more severe (ASCUS+) cytology. The overall 2-year cumulative incidence of histologically confirmed posttreatment CIN2+ was 7.0%; this could be further stratified by the HPV risk category detected at the 6-month visit after LEEP. The 2-year risk associated with HPV16 positivity was 37.0%, significantly higher than for other carcinogenic HPV types (10.8%, P < 0.001), noncarcinogenic types (1.5%, P < 0.001), or testing HPV negative (0%). Post-LEEP cytology (using a positive threshold of ASCUS+) was 78.1% (95% CI, 60.0-90.7%) sensitive for detection of posttreatment CIN2+. By comparison, PCR for carcinogenic HPV and combination testing (using a positive result from carcinogenic HPV testing or cytology as the test threshold with HPV-negative ASCUS not referred) were significantly more sensitive (96.9% for each, P = 0.03); HC2 alone was nonsignificantly more sensitive (90.6%, P = 0.3). Specificity was similar for ASCUS+ cytology (69.1%, 95% CI, 64.6-73.3%) and PCR for carcinogenic HPV (67.1%, P = 0.5), yet was lower for HC2 (63.8%, P = 0.048) and combination testing (62.9%, P = 0.02). CONCLUSION: Women who tested positive after LEEP for carcinogenic HPV types, especially HPV16, had high risk of subsequent CIN2+. HPV-based detection methods, alone or in combination with cytology, may be useful to incorporate in post-LEEP management strategies. (Cancer Epidemiol Biomarkers Prev 2006;15(5):908-14).

Clin Oncol (R Coll Radiol) 2006 May; 18(4): 300-5 (Read article online)

Katori H, Nozawat A, Tsukuda M

AIMS: To identify the relationship between p21 and p53 expression, human papilloma virus (HPV) infection and malignant transformation in sinonasal-inverted papilloma. MATERIAL AND METHODS: Nasal tissues, exophytic papilloma, inverted papilloma (IP) with dysplasia, IP with carcinoma and invasive squamous cell carcinoma (SCC) were stained with the monoclonal antibodies p21 and p53. In-situ hybridisation for HPV DNA was also carried out for types 6/11, 16/18 and 31/33. RESULTS: Significant increased staining of p21 and p53 was observed in IP with severe dysplasia, IP with carcinoma and invasive carcinoma compared with control nasal mucosa. A significant increase of dysplasia was observed in IP in the HPV 6/11 and 16/18-positive group, compared with the HPV 6/11 and 16/18-negative group. Significant decrease in expression of p21 and p53 was observed in HPV 16/18-positive IP compared with HPV 16/18-negative IP. CONCLUSIONS: Our data raise the possibility that testing for p21, p53 and HPV may help to screen out papilloma lesions with a potential for dysplasia or carcinoma.

Aust N Z J Obstet Gynaecol 2006 Jun; 46(3): 180-5 (Read article online)

Giles M, Garland S

Abstract Human papillomavirus (HPV) infection is common and causes a wide spectrum of disease. With recent advances in the development of prophylactic HPV vaccines, it is likely that these will be licensed for use in the near future. This review focuses on the science behind HPV vaccines, published clinical trial results for both prophylactic and therapeutic HPV vaccines, important issues relevant to implementation and cost-effectiveness models of HPV vaccination programs. It may be that an HPV vaccine that protects against the complications of HPV infection such as cervical cancer will be one of the most significant public health initiatives of this decade.

Pathol Int 2006 Jun; 56(6): 301-8 (Read article online)

Ogura K, Ishi K, Matsumoto T, Kina K, Nojima M, Suda K

Many studies have suggested that human papillomavirus (HPV) infection plays an important role in the carcinogenesis of the cervical adenocarcinoma. However, the prevalence of HPV infection in cervical adenocarcinoma and adenosquamous carcinoma varies among the studies. Cervical adenocarcinoma (24 cases) and adenosquamous carcinoma (16 cases), including the underlying non-neoplastic epithelium were examined for HPV-DNA using in situ polymerase chain reaction (PCR), which enabled visualization of the localization on a glass slide. In adenocarcinoma, HPV-DNA was found in 13 cases (54%) and in eight cases in underlying non-neoplastic epithelium, resulting in a total of 21 positive cases (88%). In adenosquamous carcinoma, HPV-DNA was detected in 12 cases (75%) and and the HPV-DNA localization of each component was pure adenocarcinoma, 28.6%; mixed, 54.5%; and pure squamous cell carcinoma, 83.3%. In the underlying non-neoplastic epithelium, HPV-DNA was found more frequently in the squamous epithelium (73.3%) than the cervical glands (6.3%). In conclusion, HPV-DNA was detected in 54% of adenocarcinoma, and the rate was elevated by HPV localization in the underlying non-neoplastic epithelium. HPV infection in the underlying squamous epithelium might be related to the carcinogenesis, even in cervical adenocarcinoma. HPV-DNA localization was different in each component of adenosquamous carcinoma.

Cancer Epidemiol Biomarkers Prev 2006 May; 15(5): 915-20 (Read article online)

Wiley DJ, Wiesmeier E, Masongsong E, Gylys KH, Koutsky LA, Ferris DG, Barr E, Yu Rao J

OBJECTIVE: To determine the association between tobacco smoking and serologic evidence of human papillomavirus type 16 (HPV16)-specific antibodies among HPV16 DNA-positive women. Design, Setting, and Participants: Baseline health history, physical examination, and laboratory data for 205 HPV16 DNA-positive women with no prior cytologic evidence of squamous intraepithelial lesions who were enrolled subsequently in a randomized clinical trial. Main Outcome Measure: HPV16-L1 antibody (anti-HPV16 antibody) detected from serum using RIA or ELISA. RESULTS: Eighty-seven percent (179 of 205) of women tested positive for HPV16 DNA using cervicovaginal swabs or lavage specimens, and 26 women showed similar results using swab specimens of external genitalia alone. HPV16-infected women who reported increasingly greater levels of daily cigarette smoking were less likely to test positive for anti-HPV16 antibodies than nonsmoking women (P = 0.02). Smokers were twice as likely as nonsmokers to test negative for anti-HPV16 antibodies, even after controlling for the effects of other covariates in the analyses (adjusted odds ratio, 0.5; 95% confidence limits, 0.2-0.9). Although Papanicolaou test findings and smoking characteristics were poorly correlated (r(2) = 0.01), women who showed atypical cells of unknown significance or squamous intraepithelial lesion were twice as likely to test anti-HPV16 antibody positive as women who showed normal Papanicolaou tests (adjusted odds ratio, 2.0; 95% confidence limits, 1.1-3.7). CONCLUSION: These data suggest that smoking may influence the long-term risk for cancer by perturbing early immune responses to the virus and may increase the likelihood of persistent infection. Patient education messages should alert women to this additional risk of smoking. A clinical trial of smoking cessation should be explored as a therapeutic intervention for primary HPV16 infection. (Cancer Epidemiol Biomarkers Prev 2006;15(5):915-20).

Int J Cancer 2006 May 17; (Read article online)

Vaccarella S, Lazcano-Ponce E, Castro-Garduño JA, Cruz-Valdez A, Díaz V, Schiavon R, Hernández P, Kornegay JR, Hernández-Avila M, Franceschi S

Large studies of genital human papillomavirus (HPV) infection in men are few and mainly include high-risk groups. We interviewed 779 men who requested a vasectomy in 27 public clinics in 14 states of Mexico. Exfoliated cells were obtained from the scrotum, the shaft of the penis, the top of the penis including the coronal sulcus, the glans and the opening of the meatus. HPV testing was performed using biotinylated L1 consensus primers and reverse line blot. Unconditional logistic regression was used to estimate odds ratios (ORs) of being HPV-positive and corresponding 95% confidence intervals (CIs). The prevalence of any type of HPV was 8.7%. HPV positivity was highest among men below age 25 (13.6%), and lowest among men aged 40 years or older (6.0%). The most commonly found HPV types were, in decreasing order, HPV59, 51, 6, 16 and 58. Lifetime number of sexual partners was associated with HPV positivity (OR for >/=4 vs. 1 partner = 3.7, 95% CI: 2.0-6.8), mainly on account of the strong association with number of occasional and sex-worker partners. Condom use with both regular (OR = 0.4, 95% CI: 0.1-1.0) and sex-worker (OR = 0.1, 95% CI: 0.0-0.3) partners and circumcision (OR = 0.2, 95% CI: 0.1-0.4) were inversely associated with HPV positivity. HPV prevalence in Mexican men was similar to the prevalence found in Mexican women of the same age groups. The association between HPV positivity and lifetime number of sexual partners in the present low-risk male population is one of the strongest ever reported in studies in men. Condom use and circumcision were associated with a strong reduction in HPV prevalence. (c) 2006 Wiley-Liss, Inc.

Arch Virol 2006 May 19; (Read article online)

Habig M, Smola H, Dole VS, Derynck R, Pfister H, Smola-Hess S

Human papillomaviruses (HPV) infect keratinocytes of skin and mucosa. Persistent infection can lead to the formation of benign tumors. In cases of high-risk HPV, such as HPV16 or 18, these may further progress to cancer. In order to support viral replication in suprabasal keratinocytes, the HPV E7 protein employs various strategies to keep keratinocytes in cycle and counteracts anti-proliferative signals from outside. HPV16 E7 can directly interfere with transforming growth factor-beta (TGF-beta) signalling by binding to Smad proteins mediating growth arrest. It has been speculated that this property of HPV16 E7 contributes to HPV-associated carcinogenesis. Here, we show that E7 proteins from different low- and high-risk HPV types bind to Smad 1 to 4. The E7 protein from HPV1, a low-risk HPV causing plantar warts, efficiently inhibited Smad 3-induced transcription. Our data strongly indicate that the Smad-binding capacity of E7 proteins from different HPVs may preserve keratinocyte proliferation required for the productive viral life cycle rather than promoting carcinogenesis.

Int J Cancer 2006 May 17; (Read article online)

James MA, Lee JH, Klingelhutz AJ

The E6 oncoprotein from high-risk HPV types activates human telomerase reverse transcriptase (hTERT) transcription in human keratinocytes. Studies on how E6 regulates hTERT have implicated E-box or X-box elements in the hTERT promoter (Veldman et al., Proc Natl Acad Sci USA 2003;100:8211-14; Oh et al., J Virol 2001;75:5559-66; Gewin et al., Genes Dev 2004;18:2269-82), but the mechanism of activation by E6 is still controversial and not well defined. Here, we demonstrate that induction of both hTERT expression and telomerase activity by HPV-16 E6 in early passage keratinocytes is associated with acetylation of histone H3 at the hTERT promoter, is dependent on the E6 associated protein (E6AP) and is not exclusively reliant on E-box or X-box elements. Further increases in histone acetylation of the hTERT promoter and hTERT transcriptional activity in E6 expressing cells that had been passaged extensively in culture were found to occur only with the endogenous promoter and not with an exogenously introduced hTERT promoter construct. Telomerase activity at both early and late passages, however, was dependent on E6AP expression, implying a continued reliance on E6 function for telomerase activity. Our results demonstrate that E6 induces hTERT promoter acetylation, but that further increases in telomerase activity and histone acetylation in later passage E6 expressing cells are independent of E6 activation of the core hTERT promoter. We also provide evidence that the transcription factor p300 is a potential repressor of telomerase activation and histone acetylation in the context of E6 expression. These studies give insight into how immortalization by HPV results in upregulation of hTERT and furthers our understanding of how telomerase is activated during the process of malignant transformation. (c) 2006 Wiley-Liss, Inc.