Link between chronic inflammation and human papillomavirus-induced carcinogenesis (Review)

Inflammation is a defense strategy against invading agents and harmful molecules that is activated immediately following a stimulus, and involves the release of cytokines and chemokines, which activate the innate immune response. These mediators act together to increase blood flow and vascular permeability, facilitating recruitment of effector cells to the site of injury. Following resolution of the injury and removal of the stimulus, inflammation is disabled, but if the stimulus persists, inflammation becomes chronic and is strongly associated with cancer. This is likely to be due to the fact that the inflammation leads to a wound that does not heal, requiring a constant renewal of cells, which increases the risk of neoplastic transformation. Debris from phagocytosis, including the reactive species of oxygen and nitrogen that cause damage to DNA already damaged by the leukotrienes and prostaglandins, has an impact on inflammation and various carcinogenic routes. There is an association between chronic inflammation, persistent infection and cancer, where oncogenic action is mediated by autocrine and paracrine signals, causing changes in somatic cells under the influence of the microbial genome or of epigenetic factors. Among the infectious agents associated with cancer, certain genotypes of human papillomavirus (HPV) stand out. HPV is responsible for virtually all cases of cervical cancer and a lower proportion of cancers of the vagina, vulva, anus, penis and a number of extragenital cancers. In the present review, recent advances in the mechanisms involved in the inflammatory response are presented with their participation in the process of carcinogenesis, emphasizing the role of chronic inflammation in the development of HPV-induced cervical cancer.

Assessing the impact of HAART on the incidence of defining and non-defining AIDS cancers among patients with HIV/AIDS: a systematic review

After highly active antiretroviral therapy (HAART) became widespread, several studies demonstrated changes in the incidence of defining and non-defining AIDS cancers among HIV/AIDS patients. We conducted a systematic review of observational studies evaluating the incidence of malignancies before and after the introduction of HAART in people with HIV/AIDS. Eligible studies were searched up to December 2012 in the following databases: Pubmed, Embase, Scielo, Cancerlit and Google Scholar. In this study, we determined the cancer risk ratio by comparing the pre- and post-HAART eras. Twenty-one relevant articles were found, involving more than 600,000 people with HIV/AIDS and 10,891 new cases of cancers. The risk for the development of an AIDS-defining cancer decreased after the introduction of HAART: Kaposi's sarcoma (RR=0.30, 95% CI: 0.28-0.33) and non-Hodgkin's lymphoma (RR=0.52, 95% CI: 0.48-0.56), in contrast to invasive cervical cancer (RR=1.46, 95% CI: 1.09-1.94). Among the non-AIDS-defining cancers, the overall risk increased after the introduction of HAART (RR=2.00, 95% CI: 1.79-2.23). The incidence of AIDS-defining cancers decreased and the incidence of non-AIDS-defining cancers increased after the early use of HAART, probably due to better control of viral replication, increased immunity and increased survival provided by new drugs.

Biology and pathogenesis of human osteosarcoma

Osteosarcoma (OS) is a bone tumor of mesenchymal origin, most frequently occurring during the rapid growth phase of long bones, and usually located in the epiphyseal growth plates of the femur or the tibia. Its most common feature is genome disorganization, aneuploidy with chromosomal alterations, deregulation of tumor suppressor genes and of the cell cycle, and an absence of DNA repair. This suggests the involvement of surveillance failures, DNA repair or apoptosis control during osteogenesis, allowing the survival of cells which have undergone alterations during differentiation. Epigenetic events, including DNA methylation, histone modifications, nucleosome remodeling and expression of non-coding RNAs have been identified as possible risk factors for the tumor. It has been reported that p53 target genes or those genes that have their activity modulated by p53, in addition to other tumor suppressor genes, are silenced in OS-derived cell lines by hypermethylation of their promoters. In osteogenesis, osteoblasts are formed from pluripotent mesenchymal cells, with potential for self-renewal, proliferation and differentiation into various cell types. This involves complex signaling pathways and multiple factors. Any disturbance in this process can cause deregulation of the differentiation and proliferation of these cells, leading to the malignant phenotype. Therefore, the origin of OS seems to be multifactorial, involving the deregulation of differentiation of mesenchymal cells and tumor suppressor genes, activation of oncogenes, epigenetic events and the production of cytokines.

The role of HPV-induced epigenetic changes in cervical carcinogenesis (Review)

Cervical cancer is associated with infection by certain types of human papillomaviruses (HPVs), and this affects women worldwide. Despite the improvements in prevention and cure of HPV-induced cervical cancer, it remains the second most common type of cancer in women in the least developed regions of the world. Epigenetic modifications are stable long-term changes that occur in the DNA, and are part of a natural evolutionary process of necessary adaptations to the environment. They do not result in changes in the DNA sequence, but do affect gene expression and genomic stability. Epigenetic changes are important in several biological processes. The effects of the environment on gene expression can contribute to the development of numerous diseases. Epigenetic modifications may serve a critical role in cancer cells, by silencing tumor suppressor genes, activating oncogenes, and exacerbating defects in DNA repair mechanisms. Although cervical cancer is directly related to a persistent high-risk HPV infection, several epigenetic changes have been identified in both the viral DNA and the genome of the infected cells: DNA methylation, histone modification and gene silencing by non-coding RNAs, which initiate and sustain epigenetic changes. In the present review, recent advances in the role of epigenetic changes in cervical cancer are summarized.

Chikungunya fever: a threat to global public health

Chikungunya fever is an emerging arbovirus infection, representing a serious public health problem. Its etiological agent is the Chikungunya virus (CHIKV). Transmission of this virus is mainly vector by mosquitoes of the genus Aedes, although transmission by blood transfusions and vertical transmission has also been reported. The disease presents high morbidity caused mainly by the arthralgia and arthritis generated. Cardiovascular and neurological manifestations have also been reported. The severity of the infection seems to be directly associated with the action of the virus, but also with the decompensation of preexisting comorbidities. Currently, there are no therapeutic products neither vaccines licensed to the infection CHIKV control, although several vaccine candidates are being evaluated and human polyvalent immunoglobulins anti-CHIKV had been tested. Antibodies can protect against the infection, but in sub-neutralizing concentrations can augment virus infection and exacerbate disease severity. So, the prevention still depends on the use of personal protection measures and vector control, which are only minimally effective.

No association between SNP309 promoter polymorphism in the MDM2 and cervical cancer in a study from northeastern Brazil

BACKGROUND

A functional variant in the MDM2 promoter (a T/G substitution, SNP309) was found to be associated with increased expression of MDM2 gene products and at significantly earlier age onset of tumors in both hereditary Li-Fraumeni individuals and sporadic cancer patients. We tested the hypothesis that this functional variant was associated with either risk or early age diagnosis of cervical cancer in a Brazilian population.

METHODS

A primer-introduced restriction analysis PCR assay was used to genotype the MDM2 SNP309 of 72 cervical carcinoma patients and 100 healthy women.

RESULTS

No statistically significant association was observed between SNP309 and cervical cancer. We did not find allele or genotype frequency differences between the group of patients with cancer diagnosis at an early age (younger than 40 years old) and the group of older patients.

CONCLUSIONS

Our findings suggest that SNP309 MDM2 may not be a risk factor for cervical cancer.

Innate immune response in patients with acute Zika virus infection

Innate immunity receptors (Toll-like receptors/TLRs and RIG-like receptors/RLRs) are important for the initial recognition of Zika virus (ZIKV), modulation of protective immune response, and IFN-α and IFN-β production. Immunological mechanisms involved in protection or pathology during ZIKV infection have not yet been determined. In this study, we evaluated the mRNA expression of innate immune receptors (TLR3, TLR7, TLR8, TLR9, melanoma differentiation-associated protein 5/MDA-5, and retinoic acid inducible gene/RIG-1), its adapter molecules (Myeloid Differentiation Primary Response Gene 88/Myd88, Toll/IL-1 Receptor Domain-Containing Adaptor-Inducing IFN-β/TRIF), and cytokines (IL-6, IL-12, TNF-α, IFN-α, IFN-β, and IFN-γ) in the acute phase of patients infected by ZIKV using real-time PCR in peripheral blood. Patients with acute ZIKV infection had high expression of TLR3, IFN-α, IFN-β, and IFN-γ when compared to healthy controls. In addition, there was a positive correlation between TLR3 expression compared to IFN-α and IFN-β. Moreover, viral load is positively correlated with TLR8, RIG-1, MDA-5, IFN-α, and IFN-β. On the other hand, patients infected by ZIKV showed reduced expression of RIG-1, TLR8, Myd88, and TNF-α molecules, which are also involved in antiviral immunity. Similar expressions of TLR7, TLR9, MDA-5, TRIF, IL-6, and IL-12 were observed between the group of patients infected with ZIKV and control subjects. Our results indicate that acute infection (up to 5 days after the onset of symptoms) by ZIKV in patients induces the high mRNA expression of TLR3 correlated to high expression of IFN-γ, IFN-α, and IFN-β, even though the high viral load is correlated to high expression of TLR8, RIG-1, MDA-5, IFN-α, and IFN-β in ZIKV patients.

Knowledge, attitudes, and practices related to Pap test by women, Northeastern Brazil

OBJECTIVE

To assess the knowledge, attitudes and practices of women related to the Pap test and the association between these behaviors and sociodemographic characteristics.

METHODS

A household survey with quantitative approach was conducted. A total of 267 women aged 15 to 69 years, randomly selected in a stratified manner, living in the city of São José de Mipibu, Northeastern Brazil, were interviewed in 2007. A questionnaire consisting of pre-coded open questions was administered and answers were described and analyzed, as for adequacy of knowledge, attitudes, and practices of women regarding the Pap test. Tests of association were carried out between sociodemographic characteristics and behaviors studied at a 5% significance level.

RESULTS

Although 46.1% of the women interviewed showed adequate knowledge about the Pap test, a significantly higher proportion of adequacy was seen regarding attitudes and practices, 63.3% and 64.4%, respectively. Higher schooling was associated with adequacy of knowledge, attitudes, and practices. The main barriers to the Pap test were negligence, non-requesting by their physicians, and shame.

CONCLUSIONS

The physician is the main source of information about the Pap test. However, women who more often attend medical visits, despite their good practice, show low adequacy of knowledge and attitudes related to the Pap test, which indicates that they are not receiving appropriate information on the test's purpose, advantages and benefits to women's health.

Th17 response in patients with cervical cancer

Persistent infection by high-risk human papillomavirus (HR-HPV) is the main risk factor for uterine cervical cancer (UCC). However, viral infection alone is not sufficient for the development and progression of premalignant cervical lesions for cancer. In previous years it has been suggested that the adaptive immune response triggered by the differentiation of naïve helper T cells in Th17 cells may serve an important role in disease development. It has been hypothesized that Th17 cells may be involved in the promotion of UCC, as high levels of interleukin 17 (IL17) expression have been detected in the mucosa of the uterine cervix of patients affected by the disease. However, the role of Th17 cells in the tumor development and progression remains unclear. It is believed that the immune response of the Th17 type during persistent infection of the genital tract with HR-HPV triggers chronic inflammation with a long duration with the production of IL17 and other pro-inflammatory cytokines, creating a favorable environment for tumor development. These cytokines are produced by immune system cells in addition to tumor cells and appear to function by modulating the host immune system, resulting in an immunosuppressive response as opposed to inducing an effective protective immune response, thus contributing to the growth and progression of the tumor. In the present review, the latest advances are presented about the function of Th17 cells and the cytokines produced by them in the development and progression of UCC.

[Prevalence of serologic markers of hepatitis B virus in hospital personnel]

OBJECTIVE

To verify the prevalence of the anti-HBc, anti-HBs and HBsAg markers of hepatitis B virus, and to identify the risk factors determining occupational infection with this virus among hospital personnel.

METHODS

Samples of serum from 210 persons both male and female who work in different occupations at a hospital university, were analysed. The technique employed was the immunoenzymatic assay using commercial kits.

RESULTS

As a control group, samples of serum from 45 volunteer blood donors were utilized. It was verified that 20.5% of the hospital personnel presented a positive reaction to at least one of the markers songht, as against 6.6% of the control group. The prevalence of each marker separately was: anti-HBc 8.1%, anti-HBs 5.2%, and HBsAg 2.9% in the hospital personnel; and 4.4%, 2.2% and 0.0% in the control group. The simultaneous presence of the anti-HBc and anti-HBs markers was detected in 4.3% of the workers. In the control group, the presence of the anti-HBc and anti-HBs markers was detected, isolately, with respective prevalences of 4.4% and 2.2%. Those who presented the highest rates of positivite reaction were: laboratory technicians 24.0%, nurses 23.6%, physicians 20.8%, and cleaning personnel 18.2%.

CONCLUSIONS

The findings suggest that direct contact with patients and handling of blood and other body fluids are risk factors related to occupational infection with HBV. Therefore, it is recommended that hospital personnel be vaccinated against hepatitis B.

Socioeconomic and demographic characteristics of sickle cell disease patients from a low-income region of northeastern Brazil

OBJECTIVE

To characterize the socioeconomic and demographic aspects of sickle cell disease patients from the state of Rio Grande do Norte (RN), Northeast Brazil, and their adherence to the recommended treatment.

METHODS

This cross-sectional descriptive study was performed at referral centers for the treatment of hematological diseases. One hundred and fifty-five unrelated individuals with sickle cell disease who went to these centers for outpatient visits were analyzed. All the patients, or their caregivers, were informed about the research procedures and objectives, and answered a standardized questionnaire.

RESULTS

The patients were predominantly younger than 12 years old, self-declared as mulatto, lived in small towns fairly distant from the referral center, and had low education and socioeconomic levels. Individuals who were ten or younger were diagnosed at an earlier age. Almost 50% of the patients were taking hydroxyurea, 91.4% reported having received pneumococcal/meningococcal vaccinations and 76.1% received penicillin as antibiotic prophylaxis. However, the majority of them reported having difficulties following the recommendations of the physicians, mainly in respect to attaining the prescribed medications and transportation to the referral centers.

CONCLUSION

These individuals have a vulnerable socioeconomic situation that can lead to an aggravation of their general health and thus deserve special attention from the medical and psychosocial perspectives. Thus, it is necessary to improve public policies that provide Brazilian sickle cell disease patients with better access to medical treatment, living conditions, and integration into society.

Genital tract infection with Chlamydia trachomatis in women attended at a cervical cancer screening program in Northeastern from Brazil

PURPOSE

This cross-sectional study aimed to estimate the prevalence of Chlamydia trachomatis (CT) infection alone and in combination with human papillomavirus (HPV). Furthermore, the study investigates whether the CT infection increases the risk of contracting HPV and whether the presence of both pathogens is associated with a higher prevalence of cervical lesions.

METHODS

Cervical samples of 1,134 asymptomatic women enrolled in a screening program for cervical cancer were analyzed. Two cervical specimens were collected from each patient, one for cytologic examination and the other for detection of CT by polymerase chain reaction (PCR), using a primer pair which amplifies a specific sequence of the DNA plasmid.

RESULTS

The overall prevalence rate infection was 10.9%, being 10% in the women with normal cytology, 13.8% in those with atypical squamous cells of undetermined significance (ASC-US), and 25% with low-grade squamous intraepithelial lesion (LSIL). The infection by CT did not increase the risk of acquiring HPV infection. The higher prevalence of LSIL in women co-infected with HPV and CT is possibly due to HPV.

CONCLUSION

CT infection was more prevalent in younger women aged up to 32 years, who had an early onset of reproductive activity and a history of having had multiple sexual partners lifelong may be at a greater risk of acquiring infection of the genital tract by C. trachomatis.

Knowledge, attitudes and practices regarding the Pap test among women in Northeastern Brazil

CONTEXT AND OBJECTIVE

The Papanicolaou (Pap) test has been shown to be effective in preventing cervical cancer. However, both the national and international literature shows that Pap testing has not reached the level of coverage desired. The objective of this study was to assess women's knowledge, attitudes and practices regarding the Pap test and to investigate whether there are any associations between these three factors and the women's sociodemographic characteristics.

DESIGN AND SETTING

Cross-sectional descriptive study conducted in Floriano, Piauí.

METHODS

The study was conducted among 493 women between November 2009 and December 2010. A questionnaire with precoded questions was sed, and the responses were analyzed in terms of appropriateness in relation to the Pap test.

RESULTS

The degrees of adequacy of knowledge, attitudes and practices regarding the Pap test were 36.7%, 67.2% and 69.6%, respectively. Among the main barriers against testing, absence of symptoms and a sense of embarrassment were the most notable.

CONCLUSIONS

Women who visit doctors periodically had the most appropriate practices regarding the Pap test, but their knowledge of the procedure was poor. This suggests that these women were not receiving adequate information about the benefits of periodic testing.

Chemical composition and evaluation of the antibacterial and Cytotoxic activities of the essential oil from the leaves of Myracrodruon urundeuva

BACKGROUND

This study evaluated the in vitro activity of essential oil extracted from the leaves of Myracrodruon urundeuva.

METHODS

The oil was obtained by hydro-distillation and characterized by Gas Chromatography coupled to Mass Spectrometry (GC-MS) and Gas Chromatography with Flame Ionization Detector (GC-FID). The antibacterial activity was evaluated by the broth microdilution technique and the MIF was determined by using growth indicator CTT (2,3,5-triphenyl-tetrazolium) and CBM in BHI agar. The oil's cytotoxicity was evaluated in HeLa, HEK-293, and Vero E6 cells using MTT, 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyl tetrazolium.

RESULTS

The oil showed chemical markers, including α-pinene (87.85%), trans-caryophyllene (1.57%), limonene (1.49%) and β -pinene (1.42%), and activity against all strains: Staphylococcus aureus (MIC = MBC = 0.22 mg/mL), Staphylococcus epidermidis (MIC = 0.11 mg/mL and MBC = 0.22 mg/mL), Escherichia coli (MIC = 0.88 mg/mL and MBC = 1.75 mg/mL), Pseudomonas aeruginosa (MIC = MBC = 7 mg/mL) and Salmonella Enteritidis (MIC = MBC = 0.44 mg/mL). In vitro cytotoxicity tests showed that the oil is not toxic and has slight antitumor activity.

CONCLUSIONS

We conclude that the M. urundeuva oil results are promising, with prospects of being pharmacologically viable.

Human papillomavirus infection in women attended at a cervical cancer screening service in Natal, Brazil

We analyzed cervical specimens of 202 women, aged 15 to 64 years, attended at Luis Antonio Hospital, Natal, Brazil, to determine the prevalence of HPV and identify the more frequent genotypes and risk factors for HPV infection in women attended at a cervical cancer screening service. Two specimens were collected from each patient: one for cytological examination and the other to detect HPV DNA by PCR, and typing by dot blot hybridization. A total of 54.5% of the sample had normal cytology and 45.5% had cytological alterations. HPV was detected in 24.5% of the cytologically normal women and in 59.8% of those with altered cytology. Both single and double HPV infection increased the likelihood of cytological alterations. Thirteen types of HPV were identified, most of which were high risk. HPV 16 was the most prevalent single-type infection, followed by HPV 58. The most frequent double infection was the association between HPV 56 and 57. The prevalence of HPV in cytologically normal women was greater than that reported for countries on all the continents except Africa. The inverse was observed in women with cytological alterations. The distribution of HPV types was similar to that described for the Americas, with some differences. Multiple sexual partners was the only risk factor showing an association with the presence of HPV infection.

Genital infection with herpes simplex virus types 1 and 2 in women from natal, Brazil

Objective. To evaluate the prevalence of HSV-1 and HSV-2 in pregnant and nonpregnant women, testing the correlation between DNA of the viruses with colposcopic and/or cytological changes, and evaluate association with sociodemographic characteristics and sexual activity. Methods. Included in this study were 106 pregnant and 130 nonpregnant women treated at primary health care units of Natal, Brazil, in the period 2010-2011. The patients were examined by colposcopy, and two cervical specimens were collected: one for cytology examination and another for analysis by PCR for detection of HSV-1 and HSV-2. Results. HSV-1 alone was detected in 16.0% of pregnant and 30.0% of nonpregnant women. For HSV-2, these rates were 12.3% and 15.5%, respectively. HSV-2 had a higher correlation with cytology and/or colposcopy changes than HSV-1 did. Genital HSV-1 infection was not associated with any of the variables tested, whereas HSV-2 infection was associated with ethnicity, marital status, and number of sexual partners. Conclusions. The prevalence of HSV-1 was higher than that observed for HSV-2 in both pregnant and nonpregnant women. The genital infection by HSV-2 was higher in women with changed colposcopy and/or cytology, and it was associated with ethnicity, marital status, and number of sexual partners.

Epidemiologic and clinical investigations during a chikungunya outbreak in Rio Grande do Norte State, Brazil

The first autochthonous case of chikungunya virus (CHIKV) infection in Brazil was in September 2014 in the State of Amapá, and from there it rapidly spread across the country. The present study was conducted in 2016 in the state of Rio Grande do Norte, and the aims were to describe the epidemiological and the clinical aspects of the CHIKV outbreak. Biological samples from 284 chikungunya suspected cases were screened for CHIKV and Flavivirus (FV) RNA using qRT-PCR. Negative PCR samples were also screened for anti-CHIKV and anti-FVIgM by ELISA. CHIKV RNA were detected in 125 samples mostly occurring from January through March (46%), mainly affecting adults and older adults. We found a gradual decrease in viral RNA over the disease time. Anti-CHIKV IgM was found in 47.5% after negative CHIKV qRT-PCR. Interestingly, 45.0% simultaneously had positive results for CHIKV and FV IgM, suggesting the occurrence of virus co-circulation. The most frequent symptom was fever (91%). Women presented more chance to develop nausea and abdominal pain compared to men. Our data described and allows us to better understand the clinical and epidemiological aspects of the 2016 chikungunya outbreak in Rio Grande do Norte and can help in the early clinical diagnosis of the virus.

Strength training improves body composition, muscle strength and increases CD4+ T lymphocyte levels in people living with HIV/AIDS

The establishment of physical training programs for people living with HIV/AIDS (PLWHA) has several benefits. The study aimed to analyze the effect of resistance training using prediction of intensity by subjective perception of effort (SPE) on body composition, muscle strength, and TCD4⁺ lymphocyte levels in PLWHA. This a randomized controlled trial study. Participants (11 men and 8 women), were divided in two groups: exercise group (EG) and control group (CG). The EG was submitted to 12 weeks of a resistance-training program based in the prediction of intensity by SPE. Body mass percentages were evaluated using tetrapolar bioelectrical impedance and skinfold methods. We used Flow Cytometry to quantify CD4+ T lymphocytes. Patients showed significant changes in Body Fat Percentage (Δ%=-6.23%), Lean Body Mass (Δ%=2.45%), and CD4T lymphocytes levels (Δ%=15.77%). They also showed significant increase in muscular strength presented in the test for one repetition maximum in all the evaluated exercises. Our data suggest that exercising program prescribed by SPE is capable of improving immune function, body composition, and muscular strength in PLWHA.

[Rotavirus detection in feces of children with acute diarrhea]

OBJECTIVE: To determine the prevalence of rotavirus in the etiology of acute diarrhea in children from Natal city, RN, Brazil and investigate the existence or not of a seasonal distribution of this pathogen in our environment.METHODS: Fecal samples from 1,903 children (boys and girls) with ages ranging from 1 month to 10 years, living in Natal-RN, who presented acute diarrhea episodes in a period from January 1996 to December 1998, were analyzed. We searched viral particles directly in the feces by a passive agglutination reaction using anti-rotavirus specific-group monoclonal antibodies coated latex particles.RESULTS: 151 children (7.9%) of the studied population presented a positive reaction, revealing the presence of rotavirus particles in feces. Considering, however, only the children (ages from 1 to 24 months) who are more susceptible to rotavirus infection, we verified that from 1,065 examined children, 136 of them (12.8%) presented positive reaction for rotavirus, and the great majority of all children with positive reaction (96.3%) had ages ranging from 6 to 24 months. Analysis of the distribution of the cases of rotavirus infection in the three year revealed that the incidence of infection was higher in July, August, and September.CONCLUSIONS: The results indicated rotavirus infections have an important role in the etiology of acute diarrhea cases. The majority of the acute diarrhea cases positive for rotavirus occurred during the first two years of life, reaching mainly children from 6 to 24 months, with the highest incidence of infection during the months of July, August, and September.

Human papillomavirus prevalence in women with normal cytology and with cervical cancer in Natal, Brazil

This study analyzed the prevalence of human papillomavirus (HPV) in cervical specimens obtained from women with normal cytology and with cervical cancer, in order to evaluate their correlation with health status and demographic characteristics, as well as sexual and reproductive activity in women treated at a cancer reference hospital in Natal, Northeast Brazil. A total of 158 women were divided into 2 groups according to their health status: group I comprised 110 women with normal cytology, and group II comprised 48 women with cervical cancer. Cervical smears were analyzed by cytological or histopathological examination for the detection of cytological alterations, and by PCR for HPV DNA detection using MY09/11 primers, followed by HPV genotyping by dot blot hybridization. Results showed overall HPV prevalence to be 24.5% in group I, with 19.1% of patients having single infection and 5.4% double infection. The HPV prevalence in group II was 85.4%, with 79.2% of patients having single and 6.2% double infection. We identified 10 different HPV genotypes, most with high oncogenic potential. HPV 16 was the most prevalent genotype in the two studied groups, followed by HPV 58 and HPV 18. High-risk HPV genital infection, chronological age, ethnicity, early onset of sexual and reproductive activities, multiple sexual partners and smoking increased the risk for cervical cancer.

A seminested PCR assay for detection and typing of human papillomavirus based on E1 gene sequences

HPV infection is considered one of the leading causes of cervical cancer in the world. To date, more than 180 types of HPV have been described and viral typing is critical for defining the prognosis of cancer. In this work, a seminested PCR which allow fast and inexpensively detection and typing of HPV is presented. The system is based on the amplification of a variable length region within the viral gene E1, using three primers that potentially anneal in all HPV genomes. The amplicons produced in the first step can be identified by high resolution electrophoresis or direct sequencing. The seminested step includes nine specific primers which can be used in multiplex or individual reactions to discriminate the main types of HPV by amplicon size differentiation using agarose electrophoresis, reducing the time spent and cost per analysis.