Human papillomavirus genotype as a prognostic factor in carcinoma of the uterine cervix

Prediction of carcinogenic human papillomavirus types in cervical cancer from multiparametric magnetic resonance images with machine learning-based radiomics models

PURPOSE

This study aimed to evaluate the potential of machine learning-based models for predicting carcinogenic human papillomavirus (HPV) oncogene types using radiomics features from magnetic resonance imaging (MRI).

METHODS

Pre-treatment MRI images of patients with cervical cancer were collected retrospectively. An HPV DNA oncogene analysis was performed based on cervical biopsy specimens. Radiomics features were extracted from contrast-enhanced T1-weighted images (CE-T1) and T2-weighted images (T2WI). A third feature subset was created as a combined group by concatenating the CE-T1 and T2WI subsets. Feature selection was performed using Pearson's correlation coefficient and wrapper- based sequential-feature selection. Two models were built with each feature subset, using support vector machine (SVM) and logistic regression (LR) classifiers. The models were validated using a five-fold cross-validation technique and compared using Wilcoxon's signed rank and Friedman's tests.

RESULTS

Forty-one patients were enrolled in the study (26 were positive for carcinogenic HPV oncogenes, and 15 were negative). A total of 851 features were extracted from each imaging sequence. After feature selection, 5, 17, and 20 features remained in the CE-T1, T2WI, and combined groups, respectively. The SVM models showed 83%, 95%, and 95% accuracy scores, and the LR models revealed 83%, 81%, and 92.5% accuracy scores in the CE-T1, T2WI, and combined groups, respectively. The SVM algorithm performed better than the LR algorithm in the T2WI feature subset (P = 0.005), and the feature sets in the T2WI and the combined group performed better than CE-T1 in the SVM model (P = 0.033 and 0.006, respectively). The combined group feature subset performed better than T2WI in the LR model (P = 0.023).

CONCLUSION

Machine learning-based radiomics models based on pre-treatment MRI can detect carcinogenic HPV status with discriminative accuracy.

Enhanced disease progression due to persistent HPV-16/58 infections in Korean women: a systematic review and the Korea HPV cohort study

BACKGROUND

Persistent human papillomavirus (HPV) infection is a key factor for the development and progression of cervical cancer. We sought to identify the type-specific HPV prevalence by cervical cytology and assess disease progression risk based on high-risk persistent HPV infection in South Korea.

METHODS

To investigate the HPV prevalence by Pap results, we searched seven literature databases without any language or date restrictions until July 17, 2019. To estimate the risk of disease progression by HPV type, we used the Korea HPV Cohort study data. The search included the terms "HPV" and "Genotype" and "Korea." Studies on Korean women, type-specific HPV distribution by cytological findings, and detailed methodological description of the detection assay were included. We assessed the risk of disease progression according to the high-risk HPV type related to the nonavalent vaccine and associated persistent infections in 686 HPV-positive women with atypical squamous cells of uncertain significance or low-grade squamous intraepithelial lesions from the Korea HPV Cohort Study. Type-specific HPV prevalence was the proportion of women positive for a specific HPV genotype among all HPV-positive women tested for that genotype in the systematic review.

RESULTS

We included 23 studies in our review. HPV-16 was the most prevalent, followed by HPV-58, -53, -70, -18, and -68. In women with high-grade squamous intraepithelial lesions, including cancer, HPV-16, -18, and -58 were the most prevalent. In the longitudinal cohort study, the adjusted hazard ratio of disease progression from atypical squamous cells of uncertain significance to high-grade squamous intraepithelial lesions was significantly higher among those with persistent HPV-58 (increase in risk: 3.54-5.84) and HPV-16 (2.64-5.04) infections.

CONCLUSIONS

While HPV-16 was the most prevalent, persistent infections of HPV-16/58 increased the risk of disease progression to high-grade squamous intraepithelial lesions. Therefore, persistent infections of HPV-16 and -58 are critical risk factors for cervical disease progression in Korea. Our results suggest that equal attention should be paid to HPV-58 and -16 infections and provide important evidence to assist in planning the National Immunization Program in Korea.

HPV Status and Individual Characteristics of Human Papillomavirus Infection as Predictors for Clinical Outcome of Locally Advanced Cervical Cancer

This study is aimed at searching for an informative predictor of the clinical outcome of cervical cancer (CC) patients. The study included 135 patients with locally advanced cervical cancer (FIGO stage II-III) associated with human papillomavirus (HPV) 16/18 types or negative status of HPV infection. Using logistic regression, we analyzed the influence of the treatment method, clinical and morphological characteristics, and the molecular genetic parameters of HPV on the disease free survival (DFS) of patients treated with radiotherapy or chemoradiotherapy. Multivariate analysis revealed three factors that have prognostic significance for DFS, i.e., HPV-related biomarker (HPV-negativity or HPV DNA integration into the cell genome) (OR = 9.67, p = 1.2 × 10^-4), stage of the disease (OR = 4.69, p = 0.001) and age (OR = 0.61, p = 0.025). The predictive model has a high statistical significance (p = 5.0 × 10^-8; Nagelkirk's R² = 0.336), as well as sensitivity (Se = 0.74) and specificity (Sp = 0.75). Thus, simultaneous accounting for the clinical and molecular genetic predictors (stage of the disease, patient age and HPV-related biomarker) makes it possible to effectively differentiate patients with prognostically favorable and unfavorable outcome of the disease.

Peritoneal HPV-DNA test in cervical cancer (PIONEER study): A proof of concept

The aim of this study was to investigate the prevalence of peritoneal human papillomavirus (HPV) infection in different clinical cervical cancer (CC) settings, and its association with potential clinical and/or histological factors. This is a single-center, prospective, observational study. Consecutive patients with newly diagnosed or recurrent/persistent CC, between March 2019 and April 2020, were included. A group of patients undergoing surgery for benign gynecological conditions was included as control group. All patients underwent HPV-DNA test in the cervix and in the peritoneal cavity simultaneously at time of surgery. Two-hundred seventy-two patients had cervical and peritoneal HPV test analyzed. Cervical and peritoneal HPV positivity (PHP) was found in 235 (88.0%) and 78 (28.7%) patients, respectively; the prevalence of PHP was 17.7% in early stage, 28.8% in locally advanced cervical cancer (LACC) and 46.6% in the metastatic/persistent/recurrent setting (P = .001). No control patient was found to have peritoneal HPV infection. Higher frequency of PHP was documented in patients with larger tumor size (P = .003), presence of cervical HPV 16/18 genotypes (P < .001), higher number of cervical high-risk (HR)-HPV per patient (P = .018) and peritoneal carcinomatosis (P < .001). Multivariate analysis demonstrated that lack of preoperative cervical conization in early stages (P = .030), while higher International Federation of Gynecology and Obstetrics (FIGO) stage (P = .021) and presence of cervical HPV 16/18 (P = .001) in LACC, was associated with PHP. This is a proof-of-concept study. A number of potential clinical implications, including prognosis, could be obtained by further studies.

Differential effect of GLUT1 overexpression on survival and tumor immune microenvironment of human papilloma virus type 16-positive and -negative cervical cancer

Glucose transporter-1 (GLUT1) has been proposed as a prognosticator in various cancers associated with therapeutic resistance and immune evasion; however little data is available on the role of GLUT1 in cervical cancer. Most cervical cancers are caused by human papilloma virus (HPV), but studies on the treatment response and prognosis depending on the HPV subtype, are conflicting. This hypothesis-generating study aims to investigate the prognostic impact of GLUT1 in cervical cancer, in conjunction with HPV subtype. Clinicopathologic factors, along with mRNA expression data were obtained using The Cancer Genome Atlas database. Tumor HPV status and immune cell scores were extracted from previous publications. In total, 298 patients were analyzed. High GLUT1 expression was associated with old age, squamous cell carcinoma, high tumor stage, pelvic lymph node metastases, and low hysterectomy rate. Multivariate survival analysis revealed that high GLUT1 expression (Hazard ratio (HR) 2.57, p = 0.002) and HPV16 subtype (HR 0.56, p = 0.033) were independent prognostic factors for overall survival. In the subgroup analysis, poor prognostic impact of high GLUT1 expression was maintained in HPV16-positive group (p < 0.001), but not in HPV16-negative group (p = 0.495). Decreased immune cell scores of CD8⁺ T cells, B cells, and Th1 cells by high GLUT1 expression were observed only in HPV16-positive group. In conclusion, these results suggested that GLUT1 expression and HPV16 subtype might have an independent prognostic value in cervical cancer. GLUT1-mediated immunomodulation might be an important cause of treatment failure, especially in HPV16-positive group.

Human papillomavirus genotype and prognosis of cervical cancer: Favorable survival of patients with HPV16-positive tumors

The prognostic impact of human papillomavirus (HPV) type on invasive cervical cancer (ICC) was analyzed for 137 women treated for ICC at a single institution between 1999 and 2007. The study subjects were divided into three groups according to HPV genotype: HPV16-positive (n = 59), HPV18-positive (n = 33), and HPV16/18-negative ICC (non-HPV16/18, n = 45). The median follow-up time was 102.5 months (range, 5–179). The 10-year overall survival (10y-OS) rates in women with FIGO stage I/II disease were similar among HPV genotypes: 94.7% for HPV16 (n = 39), 95.2% for HPV18 (n = 26), and 96.4% for non-HPV16/18 (n = 29). However, the 10y-OS rates in women with FIGO stage III/IV tumors were 73.7% for HPV16 (n = 20), 45.7% for HPV18 (n = 7), and 35.7% for other types (n = 16), with significantly higher survival in HPV16-positive compared with HPV16-negative ICC (10y-OS; 73.7% vs. 39.5%, P = 0.04). This difference in FIGO stage III/IV tumors remained significant after adjusting for age and histology (hazard ratio 0.30, 95% confidence interval 0.09–0.86, P = 0.02). These results suggest that detection of HPV16 DNA may be associated with a favorable prognosis in patients with FIGO stage III/IV ICC. Given that most women with FIGO stage III/IV tumors received concurrent chemoradiotherapy, this finding may imply that HPV16-positive tumors are more chemoradiosensitive.

Comparison of Siriraj liquid-based solution and standard transport media for the detection of high-risk human papillomavirus in cervical specimens

PURPOSE

To evaluate the performance of Siriraj liquid-based solution for human papillomavirus (HPV) DNA testing compared with standard transport media.

METHODS

This cross-sectional study enrolled 217 women aged 30 years or older who attended for cervical cancer screening or had abnormal cervical cytology, or were diagnosed with cervical cancer at the Department of Obstetrics-Gynecology, Siriraj Hospital from March 2015 to January 2016. We excluded patients with a history of any cervical procedures, hysterectomy, or previous treatment with pelvic irradiation or chemotherapy. Two cervical specimens were collected from each participant. The standard Cervi-Collect Specimen Collection Kit was used to preserve the first sample, and Siriraj liquid-based solution was used for the second one. All samples were sent for HPV DNA testing using the same standard high-risk HPV assay. HPV test results were recorded and statistically analyzed.

RESULTS

The results showed agreement between standard transport media and Siriraj liquid-based solution for HPV DNA testing, at a kappa value of 0.935 (P < 0.001). We found no discorrelation for the detection of HPV 16, which accounts for approximately 50% of cervical cancers. The relative sensitivity of Siriraj liquid-based solution and standard transport media in patients with high-grade cervical intraepithelial neoplasia or worse (CIN2+) is 98% (50/51). The relative specificity of Siriraj liquid-based solution and standard transport media in patients with non-CIN2+ is 98.1% (102/104).

CONCLUSION

Siriraj liquid-based solution showed almost perfect agreement with the standard transport media for HPV DNA testing. This solution, costing 2 to 3 times less than the commercially available standard media, may be an alternative option for HPV DNA testing.

Population-Based Assessment of HPV Genotype-Specific Cervical Cancer Survival: CDC Cancer Registry Sentinel Surveillance System

Background

Human papillomavirus (HPV) genotype influences the development of invasive cervical cancer (ICC); however, there is uncertainty regarding the association of HPV genotype with survival among ICC patients.

Methods

Follow-up data were collected from 693 previously selected and HPV-typed ICC cases that were part of the Centers for Disease Control and Prevention Cancer Registry Surveillance System. Cases were diagnosed between 1994 and 2005. The Kaplan-Meier method was used to estimate five-year all-cause survival. A multivariable Cox proportional hazards model was used to estimate the effect of HPV genotype on survival after adjusting for demographic, tumor, and treatment characteristics.

Results

Five-year all-cause survival rates varied by HPV status (HPV 16: 66.9%, HPV 18: 65.7%, HPV 31/33/45/52/58: 70.8%, other oncogenic HPV genotypes: 79.0%, nononcogenic HPV: 69.3%, HPV-negative: 54.0%). Following multivariable adjustment, no statistically significant survival differences were found for ICC patients with HPV 16-positive tumors compared with women with tumors positive for HPV 18, other oncogenic HPV types, or HPV-negative tumors. Women with detectable HPV 31/33/33/45/52/58 had a statistically significant 40% reduced hazard of death at five years (95% confidence interval [CI] = 0.38 to 0.95), and women who tested positive for nononcogenic HPV genotypes had a statistically significant 57% reduced hazard of death at five years (95% CI = 0.19 to 0.96) compared with women with HPV 16 tumors. Few statistically significant differences in HPV positivity, tumor characteristics, treatment, or survival were found by race/ethnicity.

Conclusions

HPV genotype statistically significantly influenced five-year survival rates among women with ICC; however, screening and HPV vaccination remain the most important factors to improve patient prognosis and prevent future cases.

Multiple HPV genotype infection impact on invasive cervical cancer presentation and survival

Background

Invasive cervical cancer (ICC) is the third most common malignant neoplasm affecting Brazilian women. Little is known about the impact of specific HPV genotypes in the prognosis of ICC. We hypothesized that HPV genotype would impact ICC clinical presentation and survival.

Methods

Women diagnosed with ICC at the Instituto do Câncer do Estado de São Paulo (ICESP) between May 2008 and June 2012 were included in the study and were followed until December 2015. HPV genotype was detected from formalin-fixed paraffin-embedded (FFPE) tumor tissue samples using Onclarity™ system (BD Viper™ LT automated system).

Results

292 patients aged 50±14 years were analyzed. HPVDNA was detected in 84% of patients. The HPV genotypes studied were: HPV16 (64%), HPV18 (10%), HPV33-58 (7%), HPV45 (5%), HPV31 (4%) and other high-risk HPV genotypes (11%). HPV genotypes showed different distributions regarding histological type and clinical stage. Patients were followed for 35±21 months. The overall survival at 5 years after diagnosis of cervical cancer was 54%. Age, clinical staging, histological type and multiple HPV genotypes infection detected in the same tumor specimen were associated with poorer overall survival on multivariate Cox proportional hazard analysis (p<0.05). No specific HPV genotype affected survival.

Conclusion

Multiple HPV genotype infection was associated with poorer ICC survival in our study, compared with single genotype infection. HPV genotyping from FFPE tumor tissue using an automated assay such as the Onclarity BD™ assay provides a simpler alternative for routine clinical use.

Impact

This is the largest study employing an automated HPV genotyping assay using FFPE of ICC. Multiple HPV genotype infection adversely influenced survival.

Prognostic value of HPV DNA status in cervical cancer before treatment: a systematic review and meta-analysis

Background

Human papillomavirus (HPV), has been recognized as an vital preliminary event in the oncogenesis of cervical cancer. But the prognostic value is not well defined, because of past studies showing conflicting results. So we conducted this meta-analysis to evaluate whether HPV DNA status was associated with prognosis in cervical cancer.

Materials and Methods

A total of 17 previously published eligible studies including 2,838 cases were identified and included in this meta-analysis. Positive HPV DNA was associated with good prognosis in patients with cervical cancer (overall survival [OS]: pooled hazard ratio (HR) = 0.610, 95% confidence interval (CI) = 0.457−0.814, P = 0.001; disease free survival [DFS]: pooled HR = 0.362, 95% CI = 0.252−0.519, P < 0.001). Furthermore, in subgroup analysis, the results revealed that the association between HPV DNA positive cervical cancers and better OS (pooled HR = 0.534, 95 % CI = 0.355–0.804, P = 0.003) in Mongoloid patients. Similarly, it existed in good OS (pooled HR = 0.628, 95 % CI 0.429−0.922, P = 0.017) and DFS (pooled HR = 0.355, 95% CI = 0.226−0.559, P < 0.001) in Caucasian patients.

Conclusions

HPV DNA status in cervical cancer may be a useful prognostic biomarker before carcinomas are treated. However, larger sample sizes and more comprehensive studies are required in the future studies to verify our findings.

Independent prognostic role of human papillomavirus genotype in cervical cancer

Background

Although the correlation of HPV genotype with cervical precursor lesions and invasive cancer has been confirmed, the role of HPV genotype in cervical cancer prognosis is less conclusive. This study aims to systematically investigate the independent prognostic role of HPV genotype in cervical cancer.

Methods

A total of 306 eligible patients provided cervical cell specimens for HPV genotyping before therapy and had a median follow-up time of 54 months after diagnosis. Survival times were measured from the date of diagnosis to the date of cervical cancer-related death (overall survival, OS) and from the date of diagnosis to the date of recurrence or metastasis (disease free survival, DFS). Log-rank tests and Cox proportional hazard models were performed to evaluate the association between HPV genotype and survival times.

Results

A total of 12 types of high-risk HPV were detected and the leading ten types belong to two species: alpha-9 and alpha-7. HPV16 and 18 were the two most common types, with the prevalence of 60.8% and 8.8%, respectively. In the univariate analysis, HPV16-positive cases were associated with better OS (P = 0.037) and HPV16-related species alpha-9 predicted better OS and DFS (both P < 0.01). After adjusting for age, FIGO stage, and therapy, HPV16 showed a hazard ratio (HR) of 0.36 (95% CI: 0.18, 0.74; P = 0.005) for OS, and alpha-9 resulted in a HR of 0.17 (95% CI: 0.08, 0.37; P < 0.001) for OS and 0.32 (95% CI: 0.17, 0.59; P < 0.001) for DFS.

Conclusions

HPV genotype poses differential prognoses for cervical cancer patients. The presence of HPV16 and its related species alpha-9 indicates an improved survival.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2465-y) contains supplementary material, which is available to authorized users.

Prognostic implication of human papillomavirus types and species in cervical cancer patients undergoing primary treatment

High-risk human papillomavirus (HPV) types are associated with cervical cancer. It is well established that individual HPV types vary in oncogenicity, but current data on their prognostic implication remain controversial. We examined the association between HPV types/species and the survival of 236 Chinese women aged 26–87 (mean 54.4) years after receiving primary treatment for cervical cancer. Overall, 45.8% were of FIGO stage I, 41.9% stage II, and 12.3% stage III. The four most prevalent types found were HPV-16 (60.2%), HPV-18 (21.6%), HPV-52 (11.9%), and HPV-58 (9.3%). Overall, 19.5% of patients had multiple-type infections, 78.4% harboured one or more alpha-9 species, and 28.8% harboured one or more alpha-7 species. After a median follow-up of 8.0 years, 156 (66.1%) patients survived. The 3-year overall survival rate was 75.5%. Factors independently associated with a poorer 3-year overall survival were age >60 years, tumour size >4 cm, lymph node involvement and treatment with radiotherapy+/-chemotherapy. Univariate analysis showed HPV-16 single-type infection was associated with a marginally poorer disease-specific survival (71.6% vs. 87.0%, HR: 1.71, 95% CI = 1.01–2.90), whereas non-HPV-16 alpha-9 species was associated with a better disease-specific survival (90.0% vs. 76.2%, HR: 0.36, 95% CI = 0.16–0.79). However, on multivariate analysis, HPV infection status irrespective of different grouping methods, including individual types, species, single-type or co-infection, did not carry any significant prognostic significance. In conclusion, we did not observe any association between infection with a particular HPV type/species and survival. An HPV type-based stratification in treatment and follow-up plan could not be recommended.

Influence of HPV type on prognosis in patients diagnosed with invasive cervical cancer

While much is known about the influence of HPV type on the progression of pre-invasive cervical lesions, the impact of HPV type on cervical cancer prognosis is less evidenced. Thus, we assessed the impact of HPV type on the survival of women diagnosed with cervical cancer. A total of 370 cases of cervical cancer were assessed. Univariate analysis is presented using Kaplan-Meier survival curves and log-rank statistics and multivariable Cox proportional hazard models were generated using age group, socio-economic deprivation, FIGO stage, differentiation and HPV type. HPV grouping was considered in a number of ways with particular reference to the presence or absence of HPV 16 and/or 18. In the univariate analysis, FIGO, age at diagnosis and treatment were associated with poorer survival (p < 0.0001) as was absence of HPV 16 and/or 18 (p = 0.0460). The 25% mortality time in the non-HPV 16/18 vs. HPV16/18 positive group was 615 days and 1,307 days respectively. An unadjusted Cox PH model based HPV16/18 vs. no HPV 16/18 resulted in a hazard ratio of 0.669 (0.450, 0.995). Adjusting for deprivation, FIGO and age group resulted in a hazard ratio of 0.609 (0.395, 0.941) p = 0.025. These data indicate that cancers associated with HPV 16 and/or 18 do not confer worse survival compared to cancers associated with other types, and may indicate improved survival. Consequently, although HPV vaccine is likely to reduce the incidence of cervical cancer it may not indirectly improve cervical cancer survival by reducing the burden of those cancers caused by HPV16/18.

Distribution of human papillomavirus genotypes in sardinian patients with oral squamous cell carcinoma

Human papillomaviruses (HPVs) seem to play an important role in the pathogenesis of gynecological carcinomas and in head and neck carcinomas. The aim of this study was to detect and genotype HPVs in fresh oral squamous cell carcinoma (OSCC) from a Sardinian population, and to determine whether HPV presence was significantly associated with the development of OSCC.

The oral mucosa tissues were obtained from 120 samples (68 OSCC and 52 control samples) taken from a Sardinian population seen at the Dental Clinic of the Department of Surgery and Odontostomatological Sciences, University of Cagliari (Italy) and the “ Ospedale SS Trinità”, Cagliari (A.S.L. 8) between 2007 and 2008. PCR was used for the detection of HPV DNA and the genotype was determined by DNA sequencing. The frequency of HPV infection was evaluated in relation to age, sex, smoking and alcohol use. Statistical analysis was performed using the SPSS 11.5 software.

The results showed the presence of HPV-DNA in 60.3% of OSCC with HPV-16 (51.2%) being the most frequent genotype. In these Sardinian OSCC patients, HPV-DNA was detected more in males (65.8%) than in females (34.1%) while controls show a 0% of HPV presence. HPV positive was highly associated with OSCC among subjects with a history of heavy tobacco and alcohol use and among those with no such history.

A greater frequency of high risk HPV presence was observed in patients with OSCC compared to health control patients. In addition these results suggested that oral HPV presence could be associated in OSCC subjects. Our results need more analyses to detect the HPV-DNA integration into tumoral cells.

Establishment of the 1st World Health Organization international standards for human papillomavirus type 16 DNA and type 18 DNA

A World Health Organization collaborative study was conducted to evaluate candidate international standards for human papillomavirus (HPV) Type 16 DNA (NIBSC code 06/202) and HPV Type 18 DNA (NIBSC code 06/206) for use in the amplification and detection steps of nucleic acid-based assays. The freeze-dried candidate international standards were prepared from bulk preparations of cloned plasmid containing full-length HPV-16 or HPV-18 genomic DNA. Nineteen laboratories from 13 countries participated in the study using a variety of commercial and in-house quantitative and qualitative assays. The data presented here indicate that, upon freeze-drying, there is no significant loss in potency for the candidate HPV-18 DNA and a slight loss in potency for the candidate HPV-16 DNA; although this is likely not scientifically relevant when assay precision is considered. In general, the individual laboratory mean estimates for each study sample were grouped +/- approximately 2 log(10) around the theoretical HPV DNA concentration of the reconstituted ampoule (1 x 10(7) HPV genome equivalents/mL). The agreement between laboratories is improved when potencies are made relative to the candidate international standards, demonstrating their utility in harmonizing amplification and detection steps of HPV-16 and -18 DNA assays. Degradation studies indicate that the candidate international standards are extremely stable and suitable for long-term use. Based on these findings, the candidate standards were established as the 1st WHO international standards for HPV-16 DNA and HPV-18 DNA, each with a potency of 5 x 10(6) international units (IU) per ampoule or 1 x 10(7) IU mL(-1) when reconstituted as directed.

Impact of human papillomavirus genotype on response to treatment and survival in patients receiving radiotherapy for squamous cell carcinoma of the cervix

To determine the clinical implications and prognostic value of the human papillomavirus (HPV) genotype, we evaluated the various HPV types in patients receiving radiotherapy for squamous cell carcinoma of the cervix. The study population included 113 invasive squamous cell carcinoma patients treated with radiation or chemoradiation between 1993 and 2002. The median age of the patients was 61 years. Tumors were classified by the International Federation of Gynecology and Obstetrics staging as stage IB in 11 patients, stage II in 39, stage III in 57 and stage IVA in 6 patients. To investigate HPV infection and its genotypes in the tumor specimens, L1 consensus PCR was performed followed by the direct nucleotide sequencing of the PCR products. Ninety-five samples (84.1%) were positive for HPV DNA. The most prevalent type was HPV-16 (34.7%). Poorer response to radiotherapy was observed in the patients with the HPV-16 genotype, in which 7 of the 33 patients had persistent disease. Only 1 of the 10 patients with HPV-58, 1 of the 5 with HPV-31 and 5 of the 10 patients with HPV-33 had a recurrence. The 5-year survival rate was 90, 80, 69.4 and 39% in the HPV-58, HPV-31, HPV-16 and HPV-33 type groups, respectively. Patients with HPV-31 and HPV-58 types were found to have better survival, whereas patients with the HPV-33 type experienced a higher risk of death. HPV genotyping may serve as a potential biomarker of response to radiation and prognosis in cervical carcinoma patients undergoing radio- or chemoradiotherapy.

Microarray analysis identifies differentially expressed genes induced by human papillomavirus type 18 E6 silencing RNA

The oncoprotein E6 of high-risk human papillomavirus (HPV) types promotes cell proliferation and contributes to carcinogenesis of HPV-positive cervical cancer cells. In this study, we used small interfering RNA (siRNA) technology to silence the E6 gene in HPV-18-transformed human cervical cell line HeLa and determined the effects of E6 gene knockdown on the cell by using microarray-based gene expression profiling coupled with gene functional classification with bioinformatics methods. Silencing RNA prepared by siRNA expression cassettes against HPV-18 E6 gene could significantly inhibit E6 gene expression and induce HeLa cells to apoptosis. The microarray analysis identified 359 differentially expressed genes containing 307 up-regulated and 52 down-regulated genes. We analyzed the gene functions and cellular pathways in detail, including cell cycle-related genes, CCNG1 and p21; apoptosis-related genes, CASP4, CASP6, IGFBP3, and DFFA; ubiquitin proteolysis pathway-related genes, UBE3A and UBE2C; keratinocyte differentiation-related genes, KRT4, KRT6E, and KRT18; and antioncogenes, RECK and VEL. In addition, it can be concluded that cellular apoptosis induced by HPV-18 E6 siRNA mainly depends on the P53 and ubiquitin proteolysis pathway to regulate gene expression, consequently inhibiting cell proliferation and promoting cell apoptosis. Meanwhile, activation of antioncogene and upper regulation of immunization-related genes signified the degression of the malignant extent of tumor cells after E6 inhibition. Our approach, which combines the use of siRNA-mediated gene silencing, microarray screening, and functional classification of differential genes, can be used in functional genomics study to elucidate the role of E6 oncogene in the carcinogenesis of HPV-18 and provide some possible targets for clinical treatment and drug development of cervical cancer.

Central European Vaccination Advisory Group (CEVAG) guidance statement on recommendations for the introduction of HPV vaccines

Vaccines against human papillomavirus (HPV), the primary causative agent in cervical cancer, are licensed. This paper contains the Central European Vaccination Advisory Group (CEVAG) guidance statement on the introduction of HPV vaccines in central Europe. Eight countries currently have medical representatives on CEVAG: the Czech Republic, Estonia, Hungary, Lithuania, Poland, Romania, Slovakia and Turkey. By raising awareness and disseminating information, CEVAG aims to promote the efficient and safe use of vaccines to prevent, control and if possible eliminate infectious diseases. In January 2008, the European Centre for Disease Prevention and Control published a report entitled Guidance for the Introduction of HPV Vaccines in EU Countries. Members of CEVAG have taken the information relevant to their countries from this report and, with consideration of local issues, produced these guidance recommendations for the introduction of HPV vaccines in the CEVAG region, which may be adapted for use in individual countries.