Development Of Cervical Intraepithelial Neoplasia Research Articles

Up-Regulation of 14-3-3σ (Stratifin) Is Associated With High-Grade CIN and High-Risk Human Papillomavirus (HPV) at Baseline but Does Not Predict Outcomes of HR-HPV Infections or Incident CIN in the LAMS Study

To assess whether the potentially high-risk (HR) human papillomavirus (HPV)-related up-regulation of 14-3-3sigma (stratifin) has implications in the outcome of HPV infections or cervical intraepithelial neoplasia (CIN) lesions, cervical biopsy specimens from 225 women in the Latin American Screening Study were analyzed for 14-3-3sigma expression using immunohistochemical analysis. We assessed its associations with CIN grade and HR HPV at baseline and value in predicting outcomes of HR-HPV infections and the development of incident CIN 1+ and CIN 2+. Expression of 14-3-3sigma increased in parallel with the lesion grade. Up-regulation was also significantly related to HR-HPV detection (P = .004; odds ratio, 2.71; 95% confidence interval, 1.37-5.35) and showed a linear relationship to HR-HPV loads (P = .003). 14-3-3sigma expression was of no value in predicting the outcomes (incident, persistent, clearance) of HR-HPV infections or incident CIN 1+ and CIN 2+. 14-3-3sigma is not inactivated in cervical carcinoma and CIN but is up-regulated on transition from CIN 2 to CIN 3. Its normal functions in controlling G(1)/S and G(2)/M checkpoints are being bypassed by HR HPV.

Up-Regulation of Plasminogen Activator Inhibitor-2 Is Associated With High-Risk HPV and Grade of Cervical Lesion at Baseline but Does Not Predict Outcomes of High-Risk HPV Infections or Incident CIN

Protease inhibitor serpin-B2 (plasminogen activator inhibitor-2 [PAI-2]) protects pRb from degradation in human papillomavirus (HPV)-18+ HeLa cells. Our objective was to assess whether the pRb-mediated HPV-suppressive effect of PAI-2 in cancer cell lines has implications in the outcome of HPV infections. Cervical biopsy specimens from 225 women were analyzed for PAI-2 expression to assess its value as a predictor of cervical intraepithelial neoplasia (CIN) grade, high-risk (HR) HPV at baseline, outcomes of HR-HPV infections, and the development of incident CIN. PAI-2 expression increased in parallel with lesion grade. Nuclear PAI-2 expression was significantly related to HR-HPV detection and had a linear relationship with HR-HPV load. PAI-2 expression was of no value in predicting the outcomes of HR-HPV infections. The same was true for PAI-2 as a predictor of surrogate end points (incident CIN 1+, CIN 2+) of progressive disease. PAI-2 expression is up-regulated on transition from CIN 2 to CIN 3. The HR-HPV suppressive effects of PAI-2 were not related to more favorable outcomes of HR-HPV infections or lower risk of disease progression to CIN.

Natural history of persistent high-risk human papillomavirus infections in Korean women

ObjectiveThis prospective study was performed to evaluate the clearance of high-risk human papillomavirus (HPV) infection and incidence of cytologic abnormality and cervical intraepithelial neoplasia (CIN) during the follow-up of persistent infection in Korean women. MethodsA total of 4170 women who were screened for cervical cancer, were aged 30 years or older, had no abnormal last Pap smear results for 3 years, had no history of treatment for cervical neoplastic disease, and were not pregnant were analyzed for high-risk HPV prevalence using the Hybrid capture (HC) II assay. The 224 women with normal cytology but positive for high-risk HPV DNA using the HC-II assay were analyzed for their clearance of HPV infection. ResultsThe median time to clearance in women with initially normal cytology was 7.5 months from initial detection (95% CI, 5.2–9.8 months). There were significant differences in the median time to clearance (4.5 vs. 14.5 months, p <0.001) of high-risk HPV infection between women with the initial relative light unit/ cutoff (RLU/CO) ratio values <10.0 and ≥10.0, as determined by the HC-II assay. In Kaplan–Meier analysis, probability of development of cytologic abnormalities, CIN and high-grade CIN was 38.2%, 21.7% and 8.5% respectively at 24 months of persistent high-risk HPV infection. ConclusionThe prevalence and clearance of high-risk infection in Korean women was similar to that in Western countries. Persistent high-risk HPV infection was associated with high viral load.

부산지역 유흥업소 종사여성으로부터 분리된 HPV16형의 발암유전자(E6/E7) 돌연변이 유형 분석

HPV-16형의 염기배열 변이는 지역적, 인종적으로 특징적인 차이가 있으며 특히 HPV-16형 E6/E7 유전자의 특정 염기 서열변이는 자궁경부암 및 자궁상피내 신생종양물의 발생을 일으키는 고위험 요인으로 알려져 있다. 본 연구는 2007년 부산지역 유흥업소 종사여성으로 분리된 HPV-16형 19건을 대상으로 E6/E7 유전자 영역(nt 34-880)을 표적으로 지역적 염기 서열 변이를 조사하였다. nucleotide 수준에서 HPV16형 E6 유전자는 T178G (n=11), T178A (n=1), T350G (n=4), A442C (n=2), A104T, A111G, C116T, G145T, T183G, C335T, G522C 등 11종의 변이주가 발견되었고, E7 유전자는 A647G (n=12), A645C, A777C, G663A, T732C, T760C, A775T, T789C, T795G 등 9종의 변이주가 발견되었다. 아미노산 수준에서는 HPV-16형 E6 단백질의 경우 D25E (n=12), L83V (n=4), E113D (n=2), MIL, Q3R, P5S, Q14H, D25N, 127R, H78Y, C140S 등 11종의 변이주를, HPV16형 E7 단백질의 경우 N29S (n=12), L28F, T72S 등 3종의 변이주를 관찰할 수 있었다. 본 연구 결과, 부산지역의 HPV-16형 E6/E7 우점 돌연변이주는 E6 D25E (75%), E7 N29S (78%)로 각각 나타났다. 앞으로 자궁경부암 환자 및 일반여성을 포함한 더 많은 모집 단을 대상으로 HPV-16형 E6/E7의 intratypic variants를 비교 조사하여 실제 HPV-16형 E6/E7 어떤 변이주가 자궁경부암 유발 위험성과의 관련성은 더 많이 연구되어져야 할 것으로 사료된다. Recent studies have reported that the distribution of HPV-16 sequence variation differs geographically, and more specifically that HPV-16 E6/E7 intratypic variants might carry a high risk for development of ICC (invasive cervical cancer) and CIN (cervical intraepithelial neoplasia) in a given population. To investigate the genetic diversities of HPV-16 E6/E7 oncogene by region, we collected nineteen HPV-16 isolates from sexually high-risk women in Busan, and analyzed the HPV-16 E6/E7 coding regions (nt 34 to 880) with HPV-16 E6/E7 specific PCR amplification. At the nucleotide levet eleven variants of the E6 genes and nine variants of the E7 genes were identified as follows: E6 T178G (n=l1), E6 T178A (n=l), E6 T350G (n=3), E6 A442C (n=2), E6 AI04T, E6 All1G, E6 C116T, E6 G145T, E6 T183G, E6 C335T, E6 G522C and E7 A647G (n=12), E7 A645C, E7 A777C, E7 G663A, E7 T732C, E7 T760C, E7 A775T, E7 T789C and E7 T795G, respectively. At the amino acid levet the isolated HPV-16 E6 and E7 genes showed eleven E6 variants: E6 D25E (n=12), E6 L83V (n=4), E6 E113D (n=2), E6 MIL, E6 Q3R, E6 P5S, E6 Q14H, E6 D25N, E6 127R, E6 H78Y, E6 C140S and three E7 variants: N29S (n=12), L28F, T72S. HPV16 E6 L83V, the dominant variant in the Caucasian population, showed relatively low frequencies in our study population. We elucidated that the dominant HPV-16 E6/E7 variants were HPV-16 E6 D25E (63.2%) and HPV-16 E7 N29S (63.2%), which were phylogenetically included in Asian lineage. Further study is needed to evaluate the risk of cervical cancer related HPV-16 E6/E7 intratypic variants in the Korean population.

Prediction of Human Papillomavirus 16 E6 Gene Expression and Cervical Intraepithelial Neoplasia Progression by Methylation Status

Human papillomavirus (HPV) infection represents the most important risk factor for the development of cervical intraepithelial neoplasia (CIN) and cervical cancer. We aimed to analyze the consequences of methylation of the E6 gene promoter in distinct stages of HPV-16-induced cellular transformation to assess its importance for disease progression. Human papillomavirus 16 was detected by sensitive polymerase chain reaction (PCR). Determination of E6 gene promoter methylation was analyzed by digestion with specific restriction endonuclease McrBC followed by PCR amplification. Expression of the E6 gene was determined by quantitative real-time PCR. Of 103 cervical smears from asymptomatic women with no cytological and colposcopic abnormalities, 20.4% were HPV-16-positive. Human papillomavirus 16 was present in 44.4% of 18 patients with CIN I, in 62.2% of 143 patients with CIN II/III, and in 74.2% of 31 cervix carcinoma specimens. The incidence of HPV-16 in all lesions compared with asymptomatic women was statistically significant (P < 0.001, Pearson chi test). Methylation was detected in 81% (n = 21) of HPV-16-positive asymptomatic smears compared with 62.5% in CIN I (n = 8), 31.5% (n = 89) in CIN II/III, and 43.4% (n = 23) in carcinomas; a statistical significance between lesions and healthy women was found (P < 0.001, Pearson chi test). Expression of E6 mRNA correlated with methylation status (P = 0.010, Mann-Whitney U test). We conclude that methylation of the E6 gene promoter in HPV-16 genome is a predictive biomarker for cervical cancer progression by regulating the expression of the E6 oncogene.

Immunological's host profile for HPV and Chlamydia trachomatis, a cervical cancer cofactor

Over 100 different genotypes of human papillomavirus (HPV) have been isolated to date, while Chlamydia trachomatis is the most common bacterial sexually-transmitted pathogen. This review considers evidence that C. trachomatis infection became a cofactor for HPV establishment and the development of cervical intraepithelial neoplasia.

Diminished IFN‐γ and IL‐10 and elevated Foxp3 mRNA expression in the cervix are associated with CIN 2 or 3

Cervical mucosal expression of cytokines involved in mediating cellular immunity is believed to influence the persistence of human papillomavirus (HPV) infection, a necessary prerequisite for the development of cervical intraepithelial neoplasia (CIN). Additionally, regulatory T (Treg) cells are increasingly understood to be important modulators of cellular immunity. Using quantitative RT-PCR, we measured, in cross-sectional design, the cervical mRNA expression of IFN-gamma, IL-10, and IL-12, as well as the Treg transcription factor Forkhead box P3 (Foxp3), in a cohort of young women representing CIN 1, 2, and 3, as well as benign histology. Higher levels of IFN-gamma and IL-10 were significantly (p <or= 0.05) associated with decreased odds of having high-grade cervical disease (CIN 2 or 3) in multivariate logistic regression models. In contrast, higher levels of mucosal Foxp3 expression were associated with increased odds of having CIN 2 or 3 (p = 0.004). In a multivariate model including cervical infection with HPV16 and/or another high-risk HPV type, Foxp3 remained higher in the CIN 2/3 group, but the difference was notably less significant (p = 0.05). These findings support a model in which diminished cellular immunity in the cervical mucosa and mucosal enrichment of Treg cells both contribute to the development of high-grade lesions.

LINEAR ARRAY Human Papillomavirus Genotyping Test Amenable to Automation by Implementation of GT-Blot 48 - A Pilot Study

Objectives: Persistent infection with high-risk human papillomavirus is associated with the development of cervical intraepithelial neoplasia and a key factor in progression to invasive cancer. The Linear Array HPV genotyping test (LA) is a valuable diagnostic tool enabling type-specific detection of DNA from 37 anogenital high- and low-risk HPV genotypes. Its value, however, is hampered by the underlying labour-intensive manual line blot technology. This study was designed to improve the suitability of LA in routine use by implementing the GT-Blot 48 instrument as an alternative instead of using the proposed manual detection protocol.

Association between human papillomavirus DNA load and development of cervical intraepithelial neoplasia and cervical cancer

The aim of the present study was to evaluate the relationship between human papillomavirus (HPV) viral load and risk of cervical intraepithelial neoplasia (CIN) and cervical cancer. HPV viral load was tested by hybrid capture (HC) II method in 69 normal women, 202 with CIN, and 236 with squamous cervical cancer (SCC). A significant difference in viral load was found between CIN I and CIN II + III. The risk of developing CIN and SCC estimated by OR (odds ratio) increased with elevated viral load (medium viral load: 13.6 for CIN and 54.6 for SCC, high viral load: 10.8 for CIN and 34.8 for SCC, respectively), with correspondent ORs (medium viral load: 11.3 for CIN and 69.4 for SCC, high viral load: 9.8 for CIN and 39.9 for SCC, respectively) after adjusted cofactors such as age, pregnancy, and so on. Hence, HPV viral load detected by HC II might be a useful predictor for women with high risk of development of CIN and cervical cancer.

Characterization of global transcription profile of normal and HPV-immortalized keratinocytes and their response to TNF treatment.

BackgroundPersistent infection by high risk HPV types (e.g. HPV-16, -18, -31, and -45) is the main risk factor for development of cervical intraepithelial neoplasia and cervical cancer. Tumor necrosis factor (TNF) is a key mediator of epithelial cell inflammatory response and exerts a potent cytostatic effect on normal or HPV16, but not on HPV18 immortalized keratinocytes. Moreover, several cervical carcinoma-derived cell lines are resistant to TNF anti-proliferative effect suggesting that the acquisition of TNF-resistance may constitute an important step in HPV-mediated carcinogenesis. In the present study, we compared the gene expression profiles of normal and HPV16 or 18 immortalized human keratinocytes before and after treatment with TNF for 3 or 60 hours.MethodsIn this study, we determined the transcriptional changes 3 and 60 hours after TNF treatment of normal, HPV16 and HPV18 immortalized keratinocytes by microarray analysis. The expression pattern of two genes observed by microarray was confirmed by Northern Blot. NF-κB activation was also determined by electrophoretic mobility shift assay (EMSA) using specific oligonucleotides and nuclear protein extracts.ResultsWe observed the differential expression of a common set of genes in two TNF-sensitive cell lines that differs from those modulated in TNF-resistant ones. This information was used to define genes whose differential expression could be associated with the differential response to TNF, such as: KLK7 (kallikrein 7), SOD2 (superoxide dismutase 2), 100P (S100 calcium binding protein P), PI3 (protease inhibitor 3, skin-derived), CSTA (cystatin A), RARRES1 (retinoic acid receptor responder 1), and LXN (latexin). The differential expression of the KLK7 and SOD2 transcripts was confirmed by Northern blot. Moreover, we observed that SOD2 expression correlates with the differential NF-κB activation exhibited by TNF-sensitive and TNF-resistant cells.ConclusionThis is the first in depth analysis of the differential effect of TNF on normal and HPV16 or HPV18 immortalized keratinocytes. Our findings may be useful for the identification of genes involved in TNF resistance acquisition and candidate genes which deregulated expression may be associated with cervical disease establishment and/or progression.

Glutathione-S-transferase M1 and T1 and cytochrome P1A1 genetic polymorphisms and susceptibility to cervical intraepithelial neoplasia in Greek women

The aim of the study was to determine the importance of genetic polymorphisms of glutathione-S-transferase T1 and M1 and cytochrome P1A1 genes in the development of cervical intraepithelial neoplasia in Greek women. This was a prospective, case-control study conducted by the Cervical Pathology and Colposcopy Unit of a University Ob/Gyn Department from 1999 to 2003. Cervical smears from 114 controls without any cytological and/or colposcopical evidence of cervical pathology and from 166 women with history of cervical intraepithelial neoplasia (56 CIN I, 54 CIN II and 56 CIN III) were examined with polymerase chain reaction for the above-mentioned genetic polymorphisms, taking also in mind their smoking attitudes. Statistical analysis was performed to detect any association between the null genotype of GSTM1 and GSTT1 genes and the CYP1A1 m1 polymorphism and the severity of cervical intraepithelial neoplasia. The distributions of the GSTT1 and GSTM1 wild-type genotypes were 57.48 and 39.75%, respectively. No woman with homozygous GSTT1 and GSTM1 null/null genotype was identified. CYP1A1 m1 polymorphism frequency was 24.49%. No woman with homozygous CYP1A1 m1/m1 genotype was detected as well. No significant difference in the frequencies of the GSTM1 and GSTT1 null alleles, and the CYP1A1 m1 polymorphism, was found between cases and controls. After application of Mantel-Haenszel chi procedure, there was no linear severity of the lesion and the frequency of these polymorphisms. According to our results, glutathione-S-transferase T1 and M1 and cytochrome P1A1 genetic polymporphisms do not appear to be a risk factor for cervical disease irrespective of smoking habits.

Association between human papillomavirus DNA load and development of cervical intraepithelial neoplasia and cervical cancer

The aim of the present study was to evaluate the relationship between human papillomavirus (HPV) viral load and risk of cervical intraepithelial neoplasia (CIN) and cervical cancer. HPV viral load was tested by hybrid capture (HC) II method in 69 normal women, 202 with CIN, and 236 with squamous cervical cancer (SCC). A significant difference in viral load was found between CIN I and CIN II + III. The risk of developing CIN and SCC estimated by OR (odds ratio) increased with elevated viral load (medium viral load: 13.6 for CIN and 54.6 for SCC, high viral load: 10.8 for CIN and 34.8 for SCC, respectively), with correspondent ORs (medium viral load: 11.3 for CIN and 69.4 for SCC, high viral load: 9.8 for CIN and 39.9 for SCC, respectively) after adjusted cofactors such as age, pregnancy, and so on. Hence, HPV viral load detected by HC II might be a useful predictor for women with high risk of development of CIN and cervical cancer.

Immune factors involved in the cervical immune response in the HIV/HPV co-infection

Aims:Immune factors influencing the progression of cervical intraepithelial neoplasia (CIN) to cancer remain poorly defined. This study investigates the expression of RANTES, MIP1α, COX1, COX2, STAT3, TGFβRI, IL10R, TNFαRII and...

Urethral cytology and penioscopy as screening tests for male consorts of females with human papilloma virus infection

Human Papilloma virus (HPV) infection of uterine cervix is known to be a very important risk factor for the development of cervical intraepithelial neoplasia and invasive cancer. This infection, that affects partners, is presently being investigated mostly in females. This study utilized a simple technique of urethral cytology and penioscopy to screen 38 male consorts of women with HPV infection of uterine cervix. A simple naked eye examination and examination under magnification of the male genitalia i.e.Penioscopy was performed. A cytologic smear was obtained from the urethra using a cytobrush. Five percent acetic acid was then applied and acetowhite areas, if any, were noted. Smears were studied for features indicative of HPV infection. 10 male consorts, all of whom were asymptomatic, showed evidence of HPV infection.

Identification of chromosomal alterations important in the development of cervical intraepithelial neoplasia and invasive carcinoma using alignment of DNA microarray data

Objective. To use microarray data to reveal regions of potential chromosomal loss or gain important in cervical intraepithelial neoplasia (CIN) and invasive cervical cancer by identifying mRNA expression biases in contiguous chromosomal regions. Methods. Data from three RNA expression microarray experiments were used: one primary experiment using cDNA arrays profiling gene expression in cervical epithelium from viral cytopathic effect to invasive cancer, one experiment using Affymetrix arrays profiling gene expression in invasive cancerous cervical epithelium, and one experiment using Affymetrix arrays profiling gene expression in CIN cervical biopsy specimens. Gene expression was aligned along chromosomes to reveal regions of significant chromosomal imbalance. Regions showing significant gain or loss and verified in more than one experiment are presented here. RT-PCR was performed to validate expression of one gene in a region. Results. Gain of 3q was detected from the CIN II ( P = 0.018), CIN III ( P = 0.005), and invasive cancer ( P = 0.0002) cDNA arrays, and gain of 12q was detected from the CIN ( P = 0.05) and invasive cancer ( P = 0.05) Affymetrix arrays. Loss of 6p was detected from the CIN III ( P = 0.004) cDNA arrays and invasive cancer ( P = 0.05) Affymetrix arrays. Loss of 4q was detected from the invasive cancer ( P = 0.04) cDNA arrays and invasive cancer ( P = 0.05) Affymetrix arrays. RAN, located in the region of gain on 12q24.3, was overexpressed in CIN and invasive cancer. Conclusions. Alignment of microarray expression data by chromosomes can be used to estimate regions of potential chromosomal aberration and identify differentially expressed genes important in the development of CIN and invasive cancer.

Human Papillomavirus Testing Before Elective Supracervical Hysterectomy

A case of cervical intraepithelial neoplasia (CIN) of the cervical stump is presented. Human papillomavirus DNA testing before elective supracervical hysterectomy may identify patients with increased risk for future development of CIN and aid in preoperative counseling for the type of surgical procedure performed.

T-cell responses to human papillomavirus type 16 among women with different grades of cervical neoplasia

Infection with high-risk genital human papillomavirus (HPV) types is a major risk factor for the development of cervical intraepithelial neoplasia (CIN) and invasive cervical carcinoma. The design of effective immunotherapies requires a greater understanding of how HPV-specific T-cell responses are involved in disease clearance and/or progression. Here, we have investigated T-cell responses to five HPV16 proteins (E6, E7, E4, L1 and L2) in women with CIN or cervical carcinoma directly ex vivo. T-cell responses were observed in the majority (78%) of samples. The frequency of CD4+ responders was far lower among those with progressive disease, indicating that the CD4+ T-cell response might be important in HPV clearance. CD8+ reactivity to E6 peptides was dominant across all disease grades, inferring that E6-specific CD8+ T cells are not vitally involved in disease clearance. T-cell responses were demonstrated in the majority (80%) of cervical cancer patients, but are obviously ineffective. Our study reveals significant differences in HPV16 immunity during progressive CIN. We conclude that the HPV-specific CD4+ T-cell response should be an important consideration in immunotherapy design, which should aim to target preinvasive disease.

Vaginal progesterone in the treatment of cervical dysplasia grade I: A phase II trial

5174 Background: Cervical intraepithelial neoplasia (CIN) grade I is a frequent HPV associated disease. The development of CIN was linked to a decrease of apoptosis and Langerhans’ cell (LC) count in the cervical epithelium, as well as to an increase in the expression of various adhesion molecules. Preliminary studies show that vaginally administered progesterone locally increases apoptosis and the number of LCs, and decreases the expression of various adhesion molecules. We hypothesized that vaginal progesterone increases the regression rate of CIN I. Methods: We are performing a prospective, non-randomized, open phase II trial with vaginal progesterone as treatment of CIN I. As of 12/5/2004, 18 patients are receiving vaginal micronized progesterone 400mg 1x daily for 10 days/month from menstrual cycle day 16–25 for 6 months. After 3 and 6 months patients are examined for possible regression, persistence, or progression of disease and treated accordingly. A total of 40 patients will be included in the study. Regression rates are compared with 40 controls managed expectantly. Results: Of the 40 controls, 14 lesions regressed within a mean observation time of 194 days. HPV status at inclusion (p=0.01), but not age, number of sexual partners, parity, smoking habits, use of contraceptive devices, and social status were associated with the regression rate. During the study period, 23 women were screened and asked to participate. Of those, only 5 refused to participate. Of the 18 progesterone treated women, already 6 had their 3-month examination. Regression was ascertained in 2 women during a mean follow-up of 103 (SD=11.1) days. Patients’ compliance is excellent, no side effects were noted. As of 12/05/04, we did not ascertain any statistical difference between women with and without progesterone treatment due to the low number of women enrolled in the active treatment arm to date. Conclusions: Vaginal progesterone is a well-established treatment option in gynecology. In women with CIN I, the participation rate and compliance is high and no side effects of the applied treatment were reproted. We expect to present more comprehensive data on the efficacy of vaginal progesterone with respect to CIN I regression rates in a few months. No significant financial relationships to disclose.

Human papillomavirus, cytomegalovirus, and adeno-associated virus infections in pregnant and nonpregnant women with cervical intraepithelial neoplasia.

Two hundred eight cervical specimens from two groups of subjects, 165 nonpregnant women and 53 pregnant women with cervical intraepithelial neoplasia (CIN) of grades I to III, were positive by PCR analyses for human papillomaviruses (HPVs), adeno-associated virus type 2 (AAV 2), and human cytomegalovirus (HCMV) in 67, 6, and 4.1% of the cases, respectively. The presence of AAV 2 infection was more frequently associated with pregnancy (17 versus 2.4%) and HPV-positive cervices (odds ratio = 6.358) than HCMV was. Increased HPV infection was strongly associated (P < 0.001) with a higher CIN grade, but there is no evidence that AAV 2 and HCMV infections have any impact on CIN development.

Efficient expression of modified human papillomavirus 16 e6/e7 fusion protein and the antitumor efficacy in a mouse model.

Infection with human papillomavirus, particularly type 16 (HPV16), is highly associated with the development of cervical intraepithelial neoplasia and cervical cancer. The two early viral oncogenes, E6 and E7, are selectively retained and constitutively expressed in tumor cells and are therefore attractive immunotherapeutic targets. Thus a vaccine strategy based on recombinant HPV16 E6/E7 fusion protein represents an efficient approach against HPV16-associated tumors. Although the expression level of HPV16 E6/E7 fusion protein was presumed to be low, direct experimental proof in vivo was lacking. To enhance the expression level and investigate its antitumor efficacy in vivo, we constructed a modified HPV16 E6/E7 fusion gene with three point-mutations and expressed it in Escherichia coli. The encoded protein, denoted mE6(1-120)/mE7(1-60), comprises 120 N-terminus amino acids of E6 and 60 N-terminus amino acids of E7 plus a histine tag, was purified on an affinity column, and subsequently characterized by Western blotting. Immunization of mice with mE6(1-120)/mE7(1-60) completely protected them against subsequent challenge and rechallenge with TC-1 tumor cells expressing HPV16 E6 and E7 proteins. In the therapeutic experiments, most mice eliminated the preexisting tumors and had a long-term protection. Consistent with the results of in vivo experiments, the splenocytes from immunized mice elicited cytotoxic T lymphocytes and specifically lysed TC-1 cells in vitro. More importantly, the expression level of mE6(1-120)/mE7(1-60) was significantly improved, meeting the necessary quantity required for a vaccine clinical trial. In conclusion, these data provide a scientific basis for the use of modified mE6(1-120)/mE7(1-60) in future human trials.