Human papillomavirus infection and cervical carcinoma

Locally advanced squamous cervical carcinoma (M0): management and emerging therapeutic options in the precision radiotherapy era

Squamous cervical carcinoma (SCC) requires particular attention in diagnostic and clinical management. New diagnostic tools, such as (positron emission tomography-magnetic resonance imaging) PET-MRI, consent to ameliorate clinical staging accuracy. The availability of new technologies in radiation therapy permits to deliver higher dose lowering toxicities. In this clinical scenario, new surgical concepts could aid in general management. Lastly, new targeted therapies and immunotherapy will have more room in this setting. The aim of this narrative review is to focus both on clinical management and new therapies in the precision radiotherapy era.

Economic and humanistic burden of external genital warts

External genital warts (EGW) are a sexually transmitted infection caused by various strains of human papillomavirus (HPV). Several studies have described the direct and indirect costs of EGW, while others have reported on the burden of EGW in terms of the impact on the quality of life (QOL) of patients. The arrival of a quadrivalent HPV vaccine that protects against both cervical cancer and EGW requires a proper understanding of the impact of vaccines on costs and QOL. Using pre-defined search terms and inclusion/exclusion criteria, we performed a systematic review of the economic and humanistic burden of EGW. The focus of our review was on literature describing the direct and indirect costs of EGW per episode of care (EoC) or per year, as well as the impact of EGW on disease-specific, generic, or preference-based QOL measures. We also reviewed the literature on the national economic burden of EGW from the perspectives of different countries. Other aspects of EGW management that can inform economic modelling studies, such as length of EoC, number of physician visits and indirect costs, were also explored. Our review sheds light on the high economic and humanistic burden of EGW and important differences in the costs between men and women, as well as the differences in health resource utilization and costs across countries. Our study also highlights the dearth of information on the impact of EGW on the QOL and productivity of patients.

Immunization with a poly (lactide co-glycolide) encapsulated plasmid DNA expressing antigenic regions of HPV 16 and 18 results in an increase in the precursor frequency of T cells that respond to epitopes from HPV 16, 18, 6 and 11

A phase II trial was conducted in subjects with human papillomavirus (HPV) associated high-grade cervical dysplasia testing the safety and efficacy of a microparticle encapsulated pDNA vaccine. Amolimogene expresses T cell epitopes from E6 and E7 proteins of HPV types 16 and 18. An analysis was performed on a subset of HLA-A2+ subjects to test whether CD8+ T cells specific to HPV 16, 18, 6 and 11 were increased in response to amolimogene immunization. Of the 21 subjects receiving amolimogene, 11 had elevated CD8+ T cell responses to HPV 16 and/or 18 peptides and seven of these also had increases to corresponding HPV 6 and/or 11 peptides. In addition, T cells primed and expanded in vitro with an HPV 18 peptide demonstrated cross-reactivity to the corresponding HPV 11 peptide. These data demonstrate that treatment with amolimogene elicits T cell responses to HPV 16, 18, 6 and 11.

[Human papillomavirus and cervical neoplasia]

Human papillomavirus (HPV) has been established as an important etiological factor for the development of cervical cancer. This DNA virus primarily infects the epithelium and can induce benign and malignant lesions of the mucous membranes and skin. Some HPVs are considered high risk due to their role in malignant progression of cervical tumors. Genital HPV infections are common and usually transient among young sexually active women. Only a small fraction of infected women develop cervical cancer, implying the involvement of environmental and genetic cofactors in cervical carcinogenesis. Classification, virology, pathology, natural history, epidemiological features of genital HPV infection, and future prospects for cervical cancer prevention with HPV vaccines will be reviewed here.

Immunohistochemical expression of p16 and p53 in vulvar intraepithelial neoplasia and squamous cell carcinoma of the vulva

This study was undertaken to examine the expression of p16 and p53 in vulvar intraepithelial neoplasia (VIN) and squamous cell carcinoma (SCC) of the vulva. We also analyzed the relationship between p16 and p53 immunoexpression in women younger vs. older than 55 years of age. Seventyseven histologic samples of vulvar tissue, treated surgically between June 2000 and November 2004 at the Complexo Hospitalar Santa Casa (Porto Alegre, Brazil), were investigated. We analyzed 28 cases of VIN, 37 cases of SCC and 12 normal vulvar tissues. The percentage of immunohistochemical positivity for p16 had the following distribution across the groups: VIN: 21.4% (6/28), cancer: 24.3% (9/37) and control: absent (p=0.202). p53 expression showed the following percentages: VIN: 60.7% (17/28), cancer: 18.9% (7/37) and control: 8.3% (1/12) (p=0.01). p16 expression in the cancer group (mean age: 63.4 years) was positive in 6 and 3 cases of women younger or older than 55 years, respectively (54.5% vs. 11.5%, p=0.01). p53 expression was not detected in young females with cancer, while it was expressed in 7/26 (26.9%) cases of the group of females older than 55 years of age (p=0.08). Our results suggest an increase in the immunohistochemical expression of p16 protein in young women with squamous cell carcinoma of the vulva, and a possible association with a low expression of p53.

Biologia molecular do câncer cervical

A carcinogênese é um processo de múltiplas etapas. Alterações no equilíbrio citogenético ocorrem na transformação do epitélio normal a câncer cervical. Numerosos estudos apoiam a hipótese de que a infecção por HPV está associada com o desenvolvimento de alterações malignas e pré-malignas do trato genital inferior. Neste trabalho são apresentadas as bases para a compreensão da oncogênese cervical. O ciclo celular é controlado por proto-oncogenes e genes supressores. Quando ocorrem mutações, proto-oncogenes tornam-se oncogenes, que são carcinogênicos e causam multiplicação celular excessiva. A perda da ação de genes supressores funcionais pode levar a célula ao crescimento inadequado. O ciclo celular também pode ser alterado pela ação de vírus, entre eles o HPV (Human Papiloma Virus), de especial interesse na oncogênese cervical. Os tipos de HPV 16 e 18 são os de maior interesse, freqüentemente associados a câncer cervical e anal. O conhecimento das bases moleculares que estão envolvidas na oncogênese cervical tem sido possível devido a utilização de técnicas avançadas de biologia molecular. A associação destas técnicas aos métodos diagnósticos clássicos, poderão levar a uma melhor avaliação das neoplasias cervicais e auxiliar no desenvolvimento de novas terapias, talvez menos invasivas e mais efetivas.

Effects of human papillomavirus type 16 E7 protein on the growth of cervical carcinoma cells and immuno-escape through the TGF-beta1 signaling pathway

OBJECTIVE

E7 is regarded as one of the main oncoproteins of high-risk human papillomaviruses (HPVs). It may affect the transforming growth factor beta 1 (TGF-beta1) signaling pathway. In this study, the relationship between HPV-16 infection and the functions of three critical factors of the TGF-beta1/Smads pathway was explored to assess the possible role of E7 in the development of cervical cancer.

METHODS

The expression of E7, TGF-beta1, TbetaR-II and Smad4 was detected by immunohistochemistry in paraffin-embedded cervical samples, and by RT-PCR and Western blotting in cervical cancer cell lines. The effect of TGF-beta1 on the growth of cervical cancer cells were tested by methyl thiazolyl tetrazolium (MTT), and the effects of HPV-16 E7 protein on normal and malignant cervical cells were investigated by flow cytometry.

RESULTS

During the progression from benign to malignant lesions, the expression levels of TGF-beta1 and Smad4 increased significantly in cervical carcinoma tissues. The expression of TGF-beta1 was positively correlated with E7 expression. In vitro experiments showed that TGF-beta1 could not inhibit the proliferation of several cervical carcinoma cell lines in long-term regulation, but could inhibit immunologic reactions of peripheral blood mononuclear cells (PBMCs). Blocking E7 expression could lower the expression level of TGF-beta1 and induce cells to enter apoptosis.

CONCLUSIONS

Our data indicate that HPV-16 E7 protein plays an important role during the development of cervical cancer by immuno-inhibition and stimulation of tumor cell proliferation through the TGF-beta1/Smads signaling pathway.

Human papillomavirus (HPV) genotyping by HPV DNA chip in cervical cancer and precancerous lesions

OBJECTIVES

The human papillomavirus (HPV) is a well-known cause of cervical cancer. HPV tests are used as an adjunct test to decrease the false-negative rate of cytological screening. However, attempts are being made to replace the cytological screening with HPV tests. Therefore, this study was performed to examine the possibility of using HPV tests as screening test.

MATERIALS AND METHODS

The results of the tests that were performed at the same time including the ThinPrep cytology, the high-risk group hybrid capture II (HC-II) test, the HPV DNA chip (HD-C) test, and a punch biopsy were compared in 400 women who were referred to us due to abnormal cytology or cervicogram. The accuracy of each test was then evaluated, and the type of virus was investigated using a HD-C test.

RESULTS

The positive predictive values detected by the high-risk group HC-II test and HD-C test according to the histological diagnosis outcomes were 56.8 and 53.8%, respectively, for cervicitis; 91.5 and 91.5%, respectively, for cervical intraepithelial neoplasia I (CIN I); 88.1% and 81.0%, respectively, for CIN II; 88.6 and 84.2%, respectively, for CIN III, and 92.5 and 88.7%, respectively, for cancer (in 53 patients). The most prevalent types of HPV according to the HPV tests were types 16, 58, 18, and 52 in which type 16 was detected in the more advanced lesions. The sensitivity was 88.4% for the ThinPrep cytology, 89.9% for the HC-II for the high-risk group, and 86.2% for the HD-C test.

CONCLUSION

These results suggest the possibility of using the HC-II and HD-C tests as screening tests, which have a similar sensitivity as the ThinPrep cytology. Nonetheless, randomized controlled trials will be needed before the actual application of the HPV tests as screening tests. Despite the fact that the importance of HPV type 16 in cancer development was confirmed, the prevalence of types 58 and 52 were relatively high compared with those found in other studies, showing a need for further studies on this subject. These HPV types need to be considered in vaccine development.

Plasma concentrations of coenzyme Q10 and tocopherols in cervical intraepithelial neoplasia and cervical cancer

Cervical intraepithelial neoplasia (CIN) may, at times, unpredictably progress to invasive carcinoma of the cervix. Epidemiological nutritional studies suggest that higher dietary consumption and circulating levels of certain micronutrients may be protective against cervical cancer. However, a preventive role of dietary antioxidants in CIN is not well established. The purpose of this cross-sectional study was to investigate the comparative plasma concentrations of three potent antioxidants, coenzyme Q(10,) alpha-tocopherol and gamma-tocopherol, in women with normal Pap smears and patients with a biopsy-confirmed histopathological lesion diagnosed as CIN or cervical cancer. Plasma concentrations of coenzyme Q(10,) alpha-tocopherol and gamma-tocopherol were measured by high-pressure liquid chromatography in both normal women without any history of abnormal Pap smears (n=48), and patients with histopathologically confirmed diagnoses of: (a) CIN I, n=98; (b) CIN II, n=49; (c) CIN III, n=10; and (d) cervical cancer, n=25. The mean plasma levels of coenzyme Q(10), alpha-tocopherol and gamma-tocopherol were significantly lower (P<0.001,<0.001, and<0.001, respectively by Kruskal-Wallis test) in patients with various grades of CIN and cervical cancer compared with controls. After controlling for age and smoking, an inverse association between histological grades of epithelial lesions and both plasma coenzyme Q(10) and alpha-tocopherol concentrations was observed. The low plasma concentrations of coenzyme Q(10) may be due to deficient dietary intake or a decrease in endogenous coenzyme Q(10) biosynthesis that may reflect increased utilization as a result of free radical reactive oxygen species induced oxidative stress. Further molecular studies on the mechanistic role of antioxidants in women with precancer cervical lesions are needed.

FTIR microspectroscopy of malignant fibroblasts transformed by mouse sarcoma virus

Fourier transform infrared microspectroscopy (FTIR-MSP), which is based on the characteristic molecular vibrational spectra of cells, was used to investigate spectral differences between normal primary rabbit bone marrow (BM) cells and bone marrow cells transformed (BMT) by murine sarcoma virus (MuSV). Primary cells, rather than cell lines, were used for this research because primary cells are similar to normal tissue cells in most of their characteristics. Our results showed dramatic changes in absorbance between the control cells and MuSV124-transformed cells. Various biological markers, such as the phosphate level and the RNA/DNA obtained, based on the analysis of the FTIR-MSP spectra, also displayed significant differences between the control and transformed cells. Preliminary results suggested that the cluster analysis performed on the FTIR-MSP spectra yielded 100% accuracy in classifying both types of cells.

Role of the human papilloma virus in the development of cervical intraepithelial neoplasia and malignancy

Human papilloma virus (HPV) is a public health problem as a sexually transmitted disease and as a critical factor in the pathogenesis of various cancers. The clinical manifestations, epidemiology, and virology that are critical to understanding the process of cervical dysplasia and neoplasia are reviewed. A discussion of the cervical transformation zone and the classification of cervical dysplasia and neoplasia leads into the importance of the Papanicolaou smear in prevention of potentially devastating sequelae of this virus. The role of the immune system in the progression of the disease and how it relates to vaccines, as well as treatment and prevention of HPV, are reviewed.

Human papillomavirus typing in HIV-positive women

OBJECTIVE

Human papillomavirus (HPV) is the major cause of cervical carcinoma and cervical intraepithelial neoplasia worldwide. Certain HPV types have a strong association with and probably a causative role in the pathogenesis of premalignant cervical lesions. Epidemiologic studies in women infected by the human immunodeficiency virus (HIV) have shown an increased incidence of squamous intraepithelial lesions (SILs), which were predominantly high-grade. Six to 30 per cent of women diagnosed with atypical squamous cells of undetermined significance (ASCUS) on a Papanicolaou (Pap) smear harbor SIL in normal screening populations. This study was undertaken to determine the presence of low-and high-risk HPV types in women infected by HIV and to correlate the results to those of the Pap smear.

STUDY DESIGN

HPV DNA typing (low- and high-risk) by Digene (Digene Corporation, Gathesburg, MD) hybrid capture methodology was performed on cervical swabs from 209 HIV-positive women. The results of HPV typing were correlated with those of the Pap smear in a retrospective analysis.

RESULTS

One hundred and one women (48%) tested positive for HPV subtypes by DNA typing by the hybrid capture method. Of these, 64 patients (63%) had Pap smears which were read as being normal, having benign cellular changes, or having ASCUS (favor reactive process). Of these, 19 patients tested positive for both high-risk and low-risk subtypes, 32 patients tested positive only for high-risk subtypes, and 13 patients tested positive only for low-risk subtypes.

CONCLUSION

HPV subtyping identifies a significant group of HIV-positive women who are at risk for developing cervical intraepithelial neoplasia, although they may not show significant abnormalities on their Pap smears.