The analysis of carcinomas of the vagina for human papillomavirus DNA

The Role of MicroRNAs in the Metastatic Process of High-Risk HPV-Induced Cancers

High-risk human papillomavirus (HPV)-driven cancers represent a major health concern worldwide. Despite the constant effort to develop and promote vaccination against HPVs, there is still a high percentage of non-vaccinated population. Furthermore, secondary prevention programs are not ubiquitous worldwide and not widely followed. Metastatic disease is the cause of the great majority of cancer-associated deaths, making it essential to determine its underlying mechanisms and to identify actionable anti-metastatic targets. Within certain types of cancer (e.g., head and neck), HPV-positive tumors show different dissemination patterns when compared with their HPV-negative counterparts, implicating HPV-related factors in the metastatic process. Among the many groups of biomolecules dysregulated by HPV, microRNAs have recently emerged as key regulators of carcinogenesis, able to control complex processes like cancer metastization. In this review, we present recent data on the role of microRNAs in the metastization of HPV-related cancers and on their possible clinical relevance as biomarkers of metastatic disease and/or as therapeutic targets.

Human papillomavirus genotype prevalence in invasive vaginal cancer from a registry-based population

OBJECTIVE

To describe the human papillomavirus (HPV) genotype distribution in invasive vaginal cancers diagnosed before the introduction of the HPV vaccine and evaluate if survival differed by HPV status.

METHODS

Four population-based registries and three residual tissue repositories provided formalin-fixed, paraffin-embedded tissue from microscopically confirmed primary vaginal cancer cases diagnosed between 1994 and 2005 that were tested by L1 consensus polymerase chain reaction with type-specific hybridization in a central laboratory. Clinical, demographic, and all-cause survival data were assessed by HPV status.

RESULTS

Sixty cases of invasive vaginal cancer were included. Human papillomavirus was detected in 75% (45) and 25% (15) were HPV-negative. HPV 16 was most frequently detected (55% [33/60]) followed by HPV 33 (18.3% [11/60]). Only one case was positive for HPV 18 (1.7%) Multiple types were detected in 15% of the cases. Vaginal cancers in women younger than 60 years were more likely to be HPV 16- or HPV 18-positive (HPV 16 and 18) than older women, 77.3% compared with 44.7% (P=.038). The median age at diagnosis was younger in the HPV 16 and 18 (59 years) group compared with other HPV-positive (68 years) and no HPV (77 years) (P=.003). The HPV distribution did not significantly vary by race or ethnicity or place of residence. The 5-year unadjusted all-cause survival was 57.4% for women with HPV-positive vaginal cancers compared with 35.7% among those with HPV-negative tumors (P=.243).

CONCLUSION

Three fourths of all vaginal cancers in the United States had HPV detected, much higher than previously found, and 57% could be prevented by current HPV vaccines.

Vaginal cells of smokers are more resistant to human papillomavirus infection than that of non-smokers

To evaluate effect of HPV and smoking on DNA double-strand breaks in vaginal samples, vaginal specimens collected from participants (n=76) were classified based on HPV and smoking status, and DNA double-strand breaks measured using comet assay. Mean tail length (31.2±18.7μm) and tail moment (2.4±2.8 arbitrary units) for HPV-positive patients were lower (p<0.001) compared with HPV-negative patients (61.7±22.6μm; 8.7±4.9AU). Never-smokers were found to have a higher level (p<0.001) of double-strand breaks (57.7±24.5μm, 7.5±5.5AU) compared with ever smokers (35.3±21.9μm; 3.4±3.7AU). Among HPV infected patients, never-smokers have more double-strand breaks compared to smokers (p<0.001) which correlated with age (p<0.001). Highly differentiated vaginal epithelium may be resistant to DNA damage associated with HPV infection and smoking, which may be attributed to adoptive survival mechanisms of vaginal epithelium.

Human papillomavirus as a favorable prognostic biomarker in squamous cell carcinomas of the vagina

OBJECTIVE

Recent evidence has confirmed two independent pathways in the development of vaginal squamous cell carcinoma (VaSCC): one related to and the other independent of human papillomavirus (HPV). The aim of our study was to evaluate whether HPV status has prognostic significance in this neoplasm.

METHODS

All confirmed primary VaSCCs diagnosed and treated from 1995 to 2009 in two institutions were retrospectively evaluated (n=57). HPV infection was detected by PCR using SPF-10 primers and typed with the INNO-LIPA HPV assay and p16(INK4a) expression by immunohistochemistry. Disease-free and overall survival (DFS and OS) were analyzed by Kaplan-Meier analysis with the log-rank test and a multivariate Cox proportional hazard's model.

RESULTS

HR-HPV DNA was detected in 70.2% patients. HPV16 was the most prevalent genotype (67.5% of cases). p16(INK4a) was positive in 97.5% HPV-positive and 17.6% HPV-negative tumors (p<.001). FIGO stage was associated with DFS (p=.042) and OS (p=.008). HPV-positive tumors showed better DFS (p=.042) and OS (p=.035) than HPV-negative tumors. Multivariate analysis confirmed better DFS and OS of HPV-positive patients independent of age and stage. This reduced risk of progression and mortality in HPV-positive patients was limited to women with FIGO stages I and II tumors (HR=0.26; 95% CI 0.10-0.69; p=0.006).

CONCLUSIONS

HPV-positive early stage (FIGO I and II) VaSCCs have a better prognosis than early HPV-negative tumors. HPV detection and/or p16(INK4a) immunostaining can be easily implemented in routine pathology and should be considered as valuable prognostic biomarkers in the study of patients with VaSCC.

Association of human papillomavirus with vulvar and vaginal intraepithelial disease: opportunities for prevention

While the majority of studies regarding the health benefits from human papillomavirus (HPV) vaccination have focused on cervical neoplasia and cancer, few have investigated how the epidemiology of vaginal and vulvar disease may be affected. To better understand how occurrence rates for vaginal and vulvar neoplasias and carcinomas may change in the future, we must have an understanding of the overall disease prevalence within a given population, the efficacy of vaccination and the proportion of cases attributable to HPV types administered in the vaccine. In this review, we will examine basic HPV epidemiology and prevalence, the molecular transformation events carried out by HPV oncoproteins, and clinical trials monitoring HPV-induced disease of the female genital tract. While precise projections of exactly how vaginal and vulvar disease prevalence will change with vaccination will require more studies, the preliminary data are promising.

HPV DNA detection and genotyping in 21 cases of primary invasive squamous cell carcinoma of the vagina

Primary invasive squamous cell carcinoma of the vagina is rare, and the role of human papilloma virus in its pathogenesis remains unclear. The aims of our study were to determine the distribution of human papilloma virus genotypes in 21 cases of primary invasive squamous cell carcinoma of the vagina and to correlate human papilloma virus genotype with histological subtypes. Patients' clinical records were reviewed for demographic data and the stage of the disease. Tumors (n=21) were classified according to the World Health Organization criteria. Human papilloma virus genotyping (INNO-LiPA HPV Genotyping) was performed in the whole series, and statistical analysis was performed with Fisher's Exact Test and with Student's t-test. The patients' age ranged from 36 to 88 (mean 65) years. Six cases were keratinizing squamous cell carcinoma, and 15 cases were non-keratinizing squamous cell carcinoma (seven non-keratinizing not otherwise specified, three basaloid, and five warty types). The median age of patients with keratinizing squamous cell carcinoma was 73.8 years and that of non-keratinizing squamous cell carcinoma patients was 61.5 years (P=0.08). Human papilloma virus DNA was detected in 17 cases (81%): 13 non-keratinizing squamous cell carcinoma (87%) and four keratinizing squamous cell carcinoma (67%) (P=0.31). The human papilloma virus genotypes identified were: 6, 11, 16, 18, 31, 33, 35, 40, and 58, with human papilloma virus 16 DNA the most prevalent (33%). Invasive squamous cell carcinoma of the vagina is frequently associated with human papilloma virus infection, and human papilloma virus 16 is the most common genotype. Although without statistical significance, keratinizing squamous cell carcinoma is more frequent in older patients, whereas non-keratinizing squamous cell carcinoma more frequently affects younger women. All studied histological subtypes are strongly associated with human papilloma virus infection.

Primary carcinoma of the vagina: factors influencing the age at diagnosis. The Radiumhemmet series 1956-96

The objective to this retrospective study of 341 cases of primary carcinoma of vagina (PCV) diagnosed between 1956 and 1996 was to find whether epidemiological, clinical, and histopathological variables were related to the age at diagnosis of patients with PCV. The univariate statistical analysis showed that younger age at diagnosis significantly correlated with a history of cervical dysplasia, hysterectomy, gynecological infections, and tumors located in the upper part of the vagina, whereas older age at diagnosis significantly correlated with late menarche and exophytically growing tumors. In the multivariate regression analysis, the remaining independent predictors were a history of cervical dysplasia and age at menarche. Further, parity >/=4 as well as nulliparity, smoking, and unstable marital status were more common among patients with PCV than among those in the general Swedish female population. This study indicates that the etiology of vaginal carcinoma may be age related. In young patients, the disease seems to be etiologically related to cervical neoplasia and thus human papillomavirus (HPV) dependent. However, in the most common age group, the older patients, there might be another (probably non-HPV-related) etiology associated with hormonal factors and trauma to the vagina.

A comparative analysis of human papillomavirus types 16 and 18 and expression of p53 gene and Ki-67 in cervical, vaginal, and vulvar carcinomas

This study aimed to investigate the correlation between HPV positivity, p53 overexpression, and cell proliferative activity in cervical, vaginal, and vulvar squamous cell carcinoma.

METHODS

Sixteen vaginal and 31 vulvar squamous cell carcinomas were examined retrospectively for overexpression of p53 gene and Ki67 antigen by immunohistochemistry and for the presence of HPV types 16 and 18 DNA using a polymerase chain reaction (PCR) method. The results were compared with those obtained from 40 cervical squamous cell carcinomas.

RESULTS

HPV type 16 or 18 DNA was detected in 21 (52.8%) of 40 cases of cervical carcinomas and p53 overexpression in one (2.5%), while HPV DNA sequences were detected in seven (43.7%) of 16 cases of vaginal carcinoma and p53 overexpression in three (18.7%). With regard to vulvar carcinoma, HPV was harbored in four (12.8%) of 31 cases and p53 overexpression in 19 (61.2%). These results indicated statistically significant inverse correlations between HPV positivity and p53 overexpression (R = -0.999, P < 0.0001). Overexpression of Ki-67 was detected in 28 (70.0%) of 40, 12 (75.0%) of 16, and 21 (67.7%) of 31, cervical, vaginal, and vulvar carcinomas, respectively. There was no significant difference among the three groups.

CONCLUSIONS

In cervical carcinoma, HPV types 16 and 18 might play a common causal role, and in vulvar carcinoma, p53 gene mutations might be a main causal factor for carcinogenesis. Vaginal carcinoma, on the other hand, is considered to have transitional characteristics between cervical and vulvar carcinoma.

A population-based study of squamous cell vaginal cancer: HPV and cofactors

BACKGROUND

Little is known about the etiology of in situ or invasive squamous cell cancer of the vagina. It is thought that some vaginal cancers may have the same etiology as cervical cancer. It is also not known whether in situ and invasive vaginal cancer share the same etiologic factors. We conducted a study to evaluate risk factors for in situ and invasive vaginal cancer and their potential relationship to prior exposure to human papillomaviruses (HPV).

METHODS

A population-based case-control study included 156 women with squamous cell in situ or invasive vaginal cancer diagnosed between January 1981 and June 1998 and 2041 control women identified through random-digit dialing in western Washington state. Cases and controls were interviewed in person and provided blood samples; archival tumor tissue was retrieved for cases. Blood samples were tested for antibodies to HPV, and tumor tissue was tested for HPV DNA.

RESULTS

Women with vaginal cancer were more likely to have five or more lifetime sexual partners (OR = 3.1, 95% CI 1.9 to 4.9), to have an early age at first intercourse (<17 years OR = 2.0, 95% CI 1.2 to 3.5), and to be current smokers at diagnosis (OR = 2.1, 95% CI 1.4 to 3.1) than control women. Approximately 30% of all cases had been treated for a prior anogenital tumor, most often of the cervix. Prior hysterectomy was a risk factor only among women who had no history of prior anogenital cancer (OR = 3.9 95% CI 2.5 to 6.1). Antibodies to HPV16 L1 were strongly related to risk of vaginal cancer (OR = 4.3, 95% CI 3.0 to 6.2). We detected HPV DNA in tumor blocks from over 80% of the patients with in situ and 60% of the patients with invasive cancers.

CONCLUSIONS

In situ and invasive vaginal neoplasia have many of the same risk factors as cervical cancer, including a strong relationship to HPV infection. Women who have been treated for a prior anogenital cancer, particularly of the cervix, have a high relative risk, although low absolute risk, of being diagnosed with vaginal cancer.

Isolation of two keratinocyte cell lines derived from HPV-positive dysplastic vaginal lesions

Explant cultures were started from human papillomavirus (HPV)-infected genital lesions in order to isolate and propagate abnormally differentiating cells from squamous intraepithelial neoplasia. A medium with high calcium concentration was used to induce terminal differentiation of cells from surrounding normal epithelium. Two cell lines with extended life-spans were established. The UT-DEC-1 cell line was derived from an HPV-33-positive mild vaginal dysplasia (VAIN I). In cultured UT-DEC-1 cells, HPV 33 DNA was detected with Southern-blot hybridization and the polymerase chain reaction (PCR) technique. The restriction pattern of HPV 33 changed during early passages and flow cytometric analysis detected a decrease in chromosomal DNA content. HPV 33 RNA from the E6-E7 region could be amplified by PCR at late passage. UT-DEC-2 cell line was derived from an HPV-16-positive moderate vaginal dysplasia (VAIN II). HPV 16 DNA was also detected in cultured cells by the PCR technique. The senescence of normal keratinocytes and growth selection in favor of aneuploid cells was observed by flow cytometric analysis at subsequent passages. Karyotype analysis showed clonal chromosomal abnormalities in both cell lines. To date, UT-DEC-1 cells have undergone 40 and UT-DEC-2 cells 25 passages. This study shows that the isolation of HPV-infected dysplastic cells can be achieved by culturing the cells in a medium with high calcium concentration. The cell lines presented provide the opportunity of evaluating the early stages of squamous-cell carcinogenesis.

A rhesus monkey model for sexual transmission of a papillomavirus isolated from a squamous cell carcinoma

Recently we molecularly cloned and characterized a papillomavirus from a lymph node metastasis of a primary penile carcinoma found in a rhesus monkey; this virus species, rhesus papillomavirus type 1 (RhPV-1), is similar to oncogenic human papillomaviruses (HPVs), such as HPV-16 or HPV-18, in that the RhPV-1 DNA was found to be integrated in the tumor cell DNA. To compare the sexual transmission and oncogenic nature of RhPV-1 with these HPVs, we undertook an extensive retrospective study of a group of rhesus monkeys whose sexual mating and offspring histories were known. These animals had mated directly with the index male mentioned above or were secondarily exposed to this virus through intermediate sexual partners. This study combines cytological, histopathological, and several complementary hybridization and DNA amplification techniques on multiple tissue samples to demonstrate the sexually transmitted nature of RhPV-1. The oncogenic potential of RhPV-1 is suggested in several of the infected animals by the presence of various degrees of neoplasia including squamous cell cancer of the cervix.