Detection and typing of human papillomavirus by e6 nested multiplex PCR

Prevalence of human papillomavirus infection in pregnant versus non-pregnant women in Brazil

PURPOSE

To investigate the prevalence of human papillomavirus (HPV) in cervical samples of pregnant and non-pregnant women in South-Brazil.

METHODS

A prospective study of 91 pregnant and 92 non-pregnant women with no previous history of cervical dysplasia or cancer was carried out. Cervical samples for HPV testing and cytology were collected in each trimester of pregnancy and in the puerperium for pregnant women and at matched intervals for the non-pregnant women. All samples were analyzed through PCR with consensus primers GP5+/GP6+. Genotyping was performed using specific primers. To control for confounding factors, the analysis of multivariate logistic regression was applied. The measure of odds ratio (OR) and the 95 % confidence interval (95 % CI) were used. The level of statistical significance was set at 5 % (P ≤ 0.05).

RESULTS

HPV DNA was detected in 23/91 (25.3 %) cervical samples from the pregnant women and in 12/92 (13 %) cervical samples from non-pregnant women (P = 0.035). There was a significant association among cervical HPV infection and young age, number of lifetime sexual partners, and the presence of abnormal cervical cytology. HPV16 and HPV18 were the viral types more frequently detected. Out of the 23 HPV-positive pregnant women, 17 (73.9 %) had normal cervical cytology.

CONCLUSION

Our results suggest a higher prevalence of HPV infection in pregnant vs. non-pregnant women. This finding may be related to the relative immunosuppression observed in pregnant women, outlining the importance of the appropriate monitoring of the viral infection in this specific population.

Sites of disruption within E1 and E2 genes of HPV16 and association with cervical dysplasia

Integration of HPV16 DNA into the host chromosome usually disrupts the E1 and/or E2 genes. The present study investigated the disruption of E1, E2 genes in a total of eighty four HPV16-positive precancerous and cervical cancer specimens derived from Greek women (seventeen paraffin-embedded cervical biopsies and sixty seven Thin Prep samples). Complete E2 and E1 genes were amplified using three and nine overlapping primer sets respectively, in order to define the sites of disruption. Extensive mapping analysis revealed that disruption/deletion events within E2 gene occurred in high grade and cervical cancer samples (x(2) test, P < 0.01), while no evidence of E2 gene disruption was documented among low grade cervical intraepithelial neoplasias. In addition, disruptions within the E1 gene occur both in high and low grade cervical intraepithelial neoplasia. This leads to the assumption that in low grade cervical intraepithelial neoplasias only E1 gene disruption was involved (Fisher's exact test, P < 0.05), while in high grade malignancies and cervical cancer cases deletions in both E1 and E2 genes occurred. Furthermore, the most prevalent site of disruption of E1 gene was located between nucleotides 1059 and 1323, while the most prevalent deleted region of the E2 gene was located between nucleotides 3172 and 3649 (E2 hinge region). Therefore, it is proposed that each population has its own profile of frequencies and sites of disruptions and extensive mapping analysis of E1 and E2 genes is mandatory in order to determine suitable markers for HPV16 DNA integration analysis in distinct populations.

Transcript profiling distinguishes complete treatment responders with locally advanced cervical cancer

Cervical cancer (CC) mortality is a major public health concern since it is the second cause of cancer-related deaths among women. Patients diagnosed with locally advanced CC (LACC) have an important rate of recurrence and treatment failure. Conventional treatment for LACC is based on chemotherapy and radiotherapy; however, up to 40% of patients will not respond to conventional treatment; hence, we searched for a prognostic gene signature able to discriminate patients who do not respond to the conventional treatment employed to treat LACC. Tumor biopsies were profiled with genome-wide high-density expression microarrays. Class prediction was performed in tumor tissues and the resultant gene signature was validated by quantitative reverse transcription–polymerase chain reaction. A 27-predictive gene profile was identified through its association with pathologic response. The 27-gene profile was validated in an independent set of patients and was able to distinguish between patients diagnosed as no response versus complete response. Gene expression analysis revealed two distinct groups of tumors diagnosed as LACC. Our findings could provide a strategy to select patients who would benefit from neoadjuvant radiochemotherapy-based treatment.

Dysregulated microRNAs involved in the progression of cervical neoplasm

PURPOSE

MicroRNAs (miRNAs) exhibit dysregulated expression in human cancer and play an important role in carcinogenesis. The aim of this study was to identify a distinct miRNA expression signature for cervical cancer and cervical intraepithelial neoplasia (CIN) and to investigate the function of deregulated miRNAs in cervical carcinoma.

METHODS

A miRNA microarray was used to compare miRNA expression profiles in cervical cancer, CIN and normal cervical tissues. Real-time RT-PCR was used to validate the expression of 9 miRNAs in 103 cervical tissues. Bioinformatics programs were used to predict potential target genes and their function. Functional studies were performed to characterize the effect on cervical cancer cells by overexpression of miR-218 and miR-21.

RESULTS

We identified deregulated miRNAs in cervical cancer and high-grade squamous intraepithelial lesions (HSIL). MiR-218 was the most downregulated (0.175-fold decrease) miRNA, and miR-21 was the most upregulated (5.67-fold increase) miRNA. In addition, the expression patterns of 9 miRNAs were validated by real-time RT-PCR. Bioinformatics analyses and functional studies indicated that miR-218 and miR-21 may be involved in cancer invasion and metastasis.

CONCLUSION

Our study demonstrated that miRNAs are aberrantly expressed in cervical cancer and cervical preneoplastic lesions. These miRNAs may be involved in the progression of cervical neoplasm as potential tumor suppressor genes or oncogenes.

Epidemiology of oral HPV in the oral mucosa in women without signs of oral disease from Yucatan, Mexico

High-risk human papillomaviruses (HR-HPV) are considered necessary for the development of cervical cancer. Furthermore, there is no doubt that some types of oral squamous cell carcinoma are associated with HR-HPV. The epidemiology of oral HPV infections in healthy subjects remains unclear due to a lack of knowledge. The objective of this study was to investigate the epidemiology of human papillomavirus infections of the oral mucosa without pathology. A cross-sectional study was performed; samples from 390 women seeking prenatal care, Pap smears, family planning or gynecological diseases were studied. Oral cells were collected by direct swab sampling. Information regarding sociodemographic status, sexual behavior, infectious diseases, contraceptive history and tobacco and alcohol consumption were obtained through direct interviews. HPV and genotypes were detected by type-specific polymerase chain reaction. Our results revealed that 14% of the women studied had an oral HPV infection. Women ≤ 20 years of age had the highest HPV prevalence (24.5%). In total, seven genotypes were identified, including the high-risk genotypes 16, 18, 58 and 59 and the low-risk genotypes 6, 81 and 13, the latter of which is a type exclusive to oral mucosa. Sexual behavior was not associated with the presence of genital HPV types in the oral mucosa. Genital HPV types were present in the oral mucosa of women without associated clinical manifestations; however, sexual behavior was not associated with infection, and therefore others routes of transmission should be explored.

Genetic characterization and clinical implications of human papillomavirus type 16 (HPV16) variants from northeastern Argentina

BACKGROUND

Human papillomavirus type 16 (HPV16) plays a central role in the development of cervical cancer. Worldwide studies indicate the existence of HPV16 variants that show different geographic distributions and oncogenic potential.

OBJECTIVE

Our goal was to describe the genetic variation of HPV16 isolates identified in urban women with different grades of cervical lesions living in northeastern Argentina.

STUDY DESIGN

We analyzed 116 HPV16-positive cervical samples (16 NLIM, 62 L-SIL, 16 H-SIL and 22 cervical cancer) from patients attending health centers in Misiones (Argentina) during 2006-13. HPV16 isolates were genetically characterized through PCR amplification and direct sequencing of 364 bp within the long control region, and the resulting sequences classified into variants based on phylogenetic analysis (lineages A, B, C and D). A potential association between HPV16 variants and lesion grade was evaluated through an odds ratio (OR) test. A temporal framework for the origin of HPV16 variants was assessed through coalescence analysis (BEAST v 1.7.5).

RESULTS

Phylogenetic analysis of HPV16 sequences showed that 92.1% of the samples clustered with lineage A, and 6.9% to lineage D. HPV16 variants from lineage D were more frequently associated with high-grade lesions and cancer (HSIL+) than lineage A variants at an OR of 13.8 (1.6-117.0). The time to most common recent ancestor (tMCRA) of all variants was 119,103 years before present (HPD 95%=48,486-197,239), a date consistent with the time frame for modern human evolution.

CONCLUSION

Our results suggest that HPV16 variants from lineage D may represent an additional risk factor for the development of cervical cancer in women living in northeastern Argentina. This study provides new information about viral isolates present in Argentina that will contribute to the monitoring of HPV16 infection in the vaccine era.

Determination of human papillomavirus 16 physical status through E1/E6 and E2/E6 ratio analysis

Human papillomavirus (HPV) 16 genome integration into the host chromosome is a crucial event during the life cycle of the virus and a major step towards carcinogenesis. The integration of HPV16 DNA promotes a constitutive high expression level of E6 and E7 oncoproteins, resulting in the extensive proliferation of the infected epithelial cells. In the present report the physical status of the HPV16 genome was studied, through determination of E1/E6 and E2/E6 DNA copy number ratios in 61 cervical samples of low- and high-grade malignancy and 8 cervical cancer samples, all of them associated with HPV16 infection. The selection of E1, E2 and E6 amplification target regions was performed according to the most prevalent deleted/disrupted sites of E1 and E2 genes. For this target selection we also considered the most conserved regions of E1, E2 and E6 genes among the same HPV16 isolates that were recently reported by our group. The analysis of HPV16 DNA form revealed a significant association among the mixed DNA forms in low-grade and high-grade malignancies, (χ2, P<0.01). The comparative analysis of E1/E6 and E2/E6 in the same cervical samples provides an accurate picture of HPV16 DNA form and may reveal whether different HPV16 DNA integrants coexist in the same cervical sample or not. This study proposes that E1/E6 and E2/E6 ratios determine with accuracy the HPV16 DNA integration pattern and may predict multiple integration events in the examined sample, thus providing significant information about the progression of cervical dysplasia.

Duplex Real-time PCR assay and SYBR green I melting curve analysis for molecular identification of HPV genotypes 16, 18, 31, 35, 51 and 66

Long-term infection with high-risk HPV genotypes is the leading cause of cervical cancer. In the present study a Duplex Real-time PCR assay was developed in order to identify HPV types 16, 18, 31, 35, 51 and 66 in three reactions, through SYBR green I melting curve analysis. The method utilizes type-specific primer sets that allowed the amplification of highly conserved regions of L1 gene. Reconstitution experiments were conducted by using HPV DNA plasmids in order to determine the sensitivity of the assay. The newly designed assay has a limit of detection of 10 copies per reaction. The most prevalent HPV genotype in single and in multiple HPV infections was HPV16 followed by HPV18, HPV51, HPV31, HPV35 and HPV66. The proposed method is a simple, specific, sensitive and cost-effective assay that can be easily incorporated in small and medium size laboratories for the rapid identification of the most clinically important HPV genotypes.

Human papillomavirus among women with atypical squamous cells of undetermined significance in southern Brazil

OBJECTIVE

To determine the prevalence of atypical squamous cells of undetermined significance (ASCUS) and human papillomavirus (HPV) genotypes in a population in southern Brazil.

METHODS

In a retrospective cross-sectional study, the prevalence of ASCUS was determined among women aged 20-60 years who were referred to a private medical center in Caxias do Sul by a gynecologist for assessment of a cervical condition between January 1, 2010, and September 30, 2011. Histologic and cytologic samples were tested for HPV, and polymerase chain reaction (PCR) was used to genotype any HPV DNA identified.

RESULTS

Among the 250 included women, 25 (10.0%) had ASCUS. HPV DNA was found in 15 (60.0%) women with ASCUS and 115 (51.1%) of the 225 without ASCUS. Viral typing showed that 7 (46.7%) HPV-positive women with ASCUS had multiple infections with up to five different genotypes. Both low- and high-risk HPV genotypes were found in ASCUS samples; the most prevalent genotypes were HPV6/HPV11 (affecting 10 [66.7%] women), HPV51 (6 [40.0%]), and HPV16 (6 [40.0%]).

CONCLUSION

ASCUS is not an indication of HPV infection. HPV screening and genotyping would benefit women with ASCUS, because treatment can be planned according to risk of carcinogenesis.

Viral infections and colorectal cancer: a systematic review of epidemiological studies

Numerous studies have found the presence of viral DNA in colorectal tumor tissues. However, whether viral infections contribute to the risk of colorectal cancer (CRC) is still under debate. We aimed to provide an overview of published epidemiological studies on the association between viral infections and CRC. A systematic literature search was performed in PubMed to find relevant studies published until 8 May 2014. Information collected included study population, sample type, laboratory method and prevalence of viral infection in cancer or precancer patients and controls. We found 41 studies that fulfilled the selection criteria, all of which had cross-sectional or case-control designs, and most of which were of small to moderate size. Viral infections included human papillomaviruses (HPV), human polyomaviruses, human herpesviruses, human bocavirus and Inoue-Melnick virus. Inconsistent results were observed across studies. Many studies reported higher viral DNA prevalence in tumor tissues than in normal noncancerous tissues either in the same patients or in CRC-free controls. However, potential contamination or temporal sequence of the infection and cancer development were often unclear. Seroprevalence studies assessing antibody titers indicative of viral infections did not find statistically significant differences between CRC cases and healthy controls. Overall published evidence on the role of viral infections in CRC etiology remains limited. Given the potential importance of viral infections and their implication for prevention, there is a strong need for large, methodologically rigorous epidemiological studies.

Tumor evolution and intratumor heterogeneity of an oropharyngeal squamous cell carcinoma revealed by whole-genome sequencing

Head and neck squamous cell carcinoma (HNSCC) is characterized by significant genomic instability that could lead to clonal diversity. Intratumor clonal heterogeneity has been proposed as a major attribute underlying tumor evolution, progression, and resistance to chemotherapy and radiation. Understanding genetic heterogeneity could lead to treatments specific to resistant and metastatic tumor cells. To characterize the degree of intratumor genetic heterogeneity within a single tumor, we performed whole-genome sequencing on three separate regions of an human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma and two separate regions from one corresponding cervical lymph node metastasis. This approach achieved coverage of approximately 97.9% of the genome across all samples. In total, 5701 somatic point mutations (SPMs) and 4347 small somatic insertions and deletions (indels)were detected in at least one sample. Ninety-two percent of SPMs and 77% of indels were validated in a second set of samples adjacent to the discovery set. All five tumor samples shared 41% of SPMs, 57% of the 1805 genes with SPMs, and 34 of 55 cancer genes. The distribution of SPMs allowed phylogenetic reconstruction of this tumor's evolutionary pathway and showed that the metastatic samples arose as a late event. The degree of intratumor heterogeneity showed that a single biopsy may not represent the entire mutational landscape of HNSCC tumors. This approach may be used to further characterize intratumor heterogeneity in more patients, and their sample-to-sample variations could reveal the evolutionary process of cancer cells, facilitate our understanding of tumorigenesis, and enable the development of novel targeted therapies.

Prevalence of human papillomavirus genotypes associated with cervical and breast cancers in iran

Cancer is a multi-step disease, and infection with a DNA virus could play a role in one or more of the steps in this pathogenic process. High-risk human papillomaviruses (HPV) are the causative agent of several cancers. In this study, we determined the prevalence and genotype distribution of HPV infection among Iranian patients with cervix lesions (CL) and breast cancer (BC). The study group consisted of postoperative tissues from patients diagnosed with cervix lesions and breast cancer. We analyzed 250 formalin-fixed, paraffin-embedded tissue blocks from 100 cervix lesions and 150 breast cancer samples. Verification of each cancer reported in a relative was sought through the pathology reports of the hospital records. Cervix lesions were collected from 100 patients with squamous metaplasia (SM, n=50), cervical intraepithelial neoplasia (CINI, n=18, CINII or III, n=8), and cervical carcinoma (CC, n=24). In this study we evaluated the prevalence of HPV by multiplex PCR in cervix lesions and breast cancer. For paraffin-embedded tissues, DNA extracted by the simple boiling method yielded higher proportions of successful gene amplification (99%) for b-actin gene. Overall prevalence of HPV infection was 6% in the SM group, 34.61% in the CIN group, 75% in the CC group, and 34.66% in the BC group. Furthermore, MY09/11 consensus PCR failed to detect 44 (55.69%) of all HPV infections and interestingly, the predominant genotype detected in all cancers was the oncogenic variant HPV16/18; about 34% of women aged 24 to 54 were infected with at least one type of HPV. Our results demonstrate that DNA derived from archival tissues that archived for less than 8 years could be used successfully for HPV genotyping by multiplex PCR. Infection with HPV was prevalent among Iranian women with CC and BC. The results indicate a likely causal role for high-risk HPV in CC and BC, and also offer the possibility of primary prevention of these cancers by vaccination against HPV in Iran.

Integrative and comparative genomic analysis of HPV-positive and HPV-negative head and neck squamous cell carcinomas

PURPOSE

The genetic differences between human papilloma virus (HPV)-positive and -negative head and neck squamous cell carcinomas (HNSCC) remain largely unknown. To identify differential biology and novel therapeutic targets for both entities, we determined mutations and copy-number aberrations in a large cohort of locoregionally advanced HNSCC.

EXPERIMENTAL DESIGN

We performed massively parallel sequencing of 617 cancer-associated genes in 120 matched tumor/normal samples (42.5% HPV-positive). Mutations and copy-number aberrations were determined and results validated with a secondary method.

RESULTS

The overall mutational burden in HPV-negative and HPV-positive HNSCC was similar with an average of 15.2 versus 14.4 somatic exonic mutations in the targeted cancer-associated genes. HPV-negative tumors showed a mutational spectrum concordant with published lung squamous cell carcinoma analyses with enrichment for mutations in TP53, CDKN2A, MLL2, CUL3, NSD1, PIK3CA, and NOTCH genes. HPV-positive tumors showed unique mutations in DDX3X, FGFR2/3 and aberrations in PIK3CA, KRAS, MLL2/3, and NOTCH1 were enriched in HPV-positive tumors. Currently targetable genomic alterations were identified in FGFR1, DDR2, EGFR, FGFR2/3, EPHA2, and PIK3CA. EGFR, CCND1, and FGFR1 amplifications occurred in HPV-negative tumors, whereas 17.6% of HPV-positive tumors harbored mutations in fibroblast growth factor receptor genes (FGFR2/3), including six recurrent FGFR3 S249C mutations. HPV-positive tumors showed a 5.8% incidence of KRAS mutations, and DNA-repair gene aberrations, including 7.8% BRCA1/2 mutations, were identified.

CONCLUSIONS

The mutational makeup of HPV-positive and HPV-negative HNSCC differs significantly, including targetable genes. HNSCC harbors multiple therapeutically important genetic aberrations, including frequent aberrations in the FGFR and PI3K pathway genes. See related commentary by Krigsfeld and Chung, p. 495.

Immunologic and metabolic characteristics of HPV-negative and HPV-positive head and neck squamous cell carcinomas are strikingly different

An HPV infection is involved in the etiology of about 25 % of head and neck squamous cell carcinomas (HNSCC). It has been postulated that a strong antitumoral immune response in HPV-positive tumors represents an important underlying mechanism for their good response to therapy. Recently, the Warburg phenomenon has returned to the center of attention because it affects antitumoral immune response and response to therapy. Accumulation of tumor cell-derived lactate inhibits cytotoxic T cells, as these, analogous to cancer cells, depend on glycolysis and lactate secretion for fulfillment of energy needs. Sparse information exists on the Warburg effect in HNSCC. This study aimed to characterize the metabolic and immunological features of HPV-negative and HPV-positive HNSCC. An immunohistochemical analysis of oropharyngeal carcinomas showed an enhanced antitumoral immune response (CD8/CD4 ratio) together with increased levels of proteins involved in transmembranous metabolite transportation (GLUT1 and CD147) and respiratory metabolism (COX5B) in HPV-positive tumors as compared to HPV-negative tumors. mRNA and Western blot analyses of an HPV-positive and HPV-negative HNSCC cell line revealed metabolic characteristics similar to the in vivo situation. Additionally, the HPV-negative cell line showed stronger extracellular lactate accumulation. In contrast, the HPV-positive cell line presented with better adaption to lactic acidosis suggesting an ability to metabolize lactate. Our results indicate that HPV-positive and HPV-negative carcinomas do not only differ in terms of tumor immune microenvironment, but also in terms of tumor metabolism, characterized by an increased glucose and respiratory metabolism together with decreased lactate accumulation in HPV-positive HNSCC. Therefore, targeting metabolic pathways could represent a promising adjunct in the therapy of HPV-positive HNSCC.

Impact of human papillomavirus coinfections on the risk of high-grade squamous intraepithelial lesion and cervical cancer

OBJECTIVE

The molecular and epidemiologic effect of human papillomavirus (HPV) coinfections in the risk of developing cervical cancer is yet unclear. The aim of this study was to determine the frequency HPV coinfections at different stages of cervical lesions in the development of cervical cancer and the impact of HPV specific type interactions on high-grade squamous intraepithelial lesions (HSIL) and invasive cervical cancer (ICC) risk.

METHODS

HPV testing was performed in 931 cervical samples diagnosed as: negative for intraepithelial lesion or malignancy (NILM); low-grade squamous intraepithelial lesion (LSIL); HSIL; and ICC. For HPV detection and typing two sets of primers from the L1 region were used in the polymerase chain reaction method (PCR) (MY09/MY11/HMB01 and L1C1/L1C2.1/L1C2.2) and HPV type was determined by PCR product sequence. To look for multiple HPV infections, the E6 nested multiplex PCR method was performed in all DNA samples. Odds ratios were calculated as indexes of the strength of the association between the sample category (LSIL/NILM or ICC/HSIL) and the presence of a given viral combination.

RESULTS

In HPV positive samples, coinfections are as common in ICC/HSIL as in LSIL/NILM (47.12% and 40.17%, respectively). There is an increased risk to ICC/HSIL when multiple high-risk HPV types are present. The coinfection of HPV68 with HPV16 increases the risk of ICC/HSIL (OR=14.54, P=0.012, after multivariate adjustment), related to the presence of HPV16 or HPV68 alone.

CONCLUSIONS

These results sustain that specific HPV coinfections confer an increased risk to develop ICC/HSIL.

Gene chip technology used in the detection of HPV infection in esophageal cancer of Kazakh Chinese in Xinjiang Province

This study was aimed to screen human papillomavirus (HPV) types associated with esophageal squamous cell carcinoma of Kazakh in Xinjiang using the gene chip technique and study the clinical significance of this application. The DNAs were collected from esophageal squamous cell carcinoma tissues and healthy esophageal mucosa of Kazakh adults in Xinjiang, and amplified firstly using HPV MY09/11 and then using HPV G5+/6+ to screen positive HPV specimens. These positive specimens were further detected by the gene chip technique to screen highly pathogenic HPV types. After determination with nested PCR amplification with HPV MY09/11 and G5+/6+, the infection rate of HPV was 66.67% in the esophageal squamous cell carcinoma group and 12.12% in the healthy control group. By testing the positive HPV specimens from the esophageal squamous cell carcinoma group, the infection rate of HPV16 was 97.72% and the co-infection rate of HPV16 and HPV18 was 2.27%. HPV16 infection may be involved in the development of esophageal squamous cell carcinoma in Xinjiang Hazakh adults.

A case of recurrent respiratory papillomatosis with malignant transformation, HPV11 DNAemia, high L1 antibody titre and a fatal papillary endocardial lesion

Background

Recurrent respiratory papillomatosis (RRP) is a rare disease, which is characterised by the growth of papillomavirus-induced papillomas within the respiratory tract. Malignant transformation occurs in less than 1% of the cases.

Case presentation

We report a case of human papillomavirus (HPV) type 11-associated juvenile-onset RRP (JORRP) initially diagnosed at the age of two years. Remarkably high copy numbers of HPV11 DNA and antibody titres targeting the capsid protein L1 were detected in the patient’s serum. The patient developed squamous cell carcinomas in both lungs and extraordinarily an HPV11 DNA-positive papillary endocardial lesion in the left atrium of the heart, which caused thromboembolic events leading to the patient’s death at 19 years old.

Conclusion

We here report a severe case of JORRP hallmarked by HPV11 DNAemia and very high antibody titres directed against the major viral capsid protein L1. Furthermore, the extent of malignant transformation and the discovery of a very rare fatal endocardial lesion highlight the unpredictability of JORRP and the complexity of its clinical management.

Nested Multiplex (NMPCR) Detection of Human Papillomavirus (HPV) 16 and 18 in Pre-invasive Lesions and its Implication in Screening of Carcinoma Cervix (CaCx)

INTRODUCTION

Carcinoma cervix (CaCx) is a preventable disease and is caused by certain high risk Papillomaviruses. In the present study, our aim was to investigate the utility of Nested Multiplex Polymerase Chain Reaction (NMPCR) in detecting Human Papillomavirus (HPV) 16 and 18 in cervical scrapes/biopsy samples and to correlate with cervical cytology/ histopathology findings.

METHODS

A total of 119 females were subjected for Papanicolaou smear examination of cervical scrapes and/or histopathological examination of cervical tissues. These samples were also subjected to nested multiplex PCR targeting HPV 16/ 18 specific E6/7 gene sequences.

RESULTS

HPV 16/18 were detected in 33.6% (40/119) cases included in the study. The overall HPV 16/ 18 positivity among cases with Negative for Intraepithelial Lesion or Malignancy, Low grade Squamous Intraepithelial Lesion, and High grade Squamous Intraepithelial Lesion was observed to be 20.8%, 44%, and 66.7% respectively. Positivity for HPV 16 in cases with Squamous Cell Carcinoma (SCC) was found to be 80%. HPV positivity among subjects reported with reactive cellular changes, a sub category of Negative for Intraepithelial Lesion or Malignancy, was observed to be 26.6%.

CONCLUSION

HPV 16 and 18 positivity in cases reported with different stages of pre invasive lesions of CaCx, particularly in the subcategory reactive cellular changes of Negative for Intraepithelial Lesion or Malignancy, indicates that NMPCR detection of HPV 16/ 18 may be used as a screening tool for CaCx in conjunction with Papanicolaou smear examination.

High-risk human papillomavirus infection in different histological subtypes of renal cell carcinoma

Limited data exist regarding whether a high-risk human papillomavirus (HR-HPV) infection increases the risk of developing renal cell carcinoma. The aim of this study was to investigate whether HPV infection has a role in the pathogenesis or development of a certain histological subtype of renal cell carcinoma. Formalin-fixed paraffin-embedded (FFPE) specimens of 122 patients with histopathologically proven renal cell carcinoma and their respective peritumoral tissues were examined. The presence of HPV-DNA was determined by a combination of MY/GP+ consensus primers and HPV-16/18 type specific nested PCRs followed by direct sequencing. Catalyzed signal-amplified colorimetric in situ hybridization (CSAC-ISH) technique was applied to determine the physical status of viral genome. The expression of p16INK4a and HPV L1 capsid proteins was evaluated using immunohistochemistry. HPV genome was detected in 37 (30.3%) tumor specimens and their four (4.1%) corresponding peritumoral tissues. HPV-18 was the most common viral type identified followed by HPV-16 and 58. Immunoexpression of p16INK4a was detected in 24 (20.3%) cases. Data analysis showed a significant correlation between p16INK4a expression and the presence of HR-HPV DNA (P < 0.001). CSAC-ISH analysis confirmed HR-HPV infection in 45% of tumors, which were previously tested positive for HPV-DNA. Diffuse signal pattern was identified in 15 (83.3%) samples whereas a mixed pattern of diffuse and punctate signals was only detectable in three cases. The results indicate an association of HR-HPV types with renal cell carcinoma. It is proposed that HPV infection in high-grade tumors might precede disease progression in a number of tumors, particularly of the papillary subtype.

Absence of human papillomavirus infection and activation of PI3K-AKT pathway in cervical clear cell carcinoma

OBJECTIVE

Cervical cancer is the second most common cancer in females worldwide, and the majority of squamous cell carcinomas and adenocarcinomas are associated with high-risk human papillomavirus (HPV) infection. However, the relationship between clear cell carcinoma of the cervix (CCCC) and HPV is unclear. In this study, we sought to determine if HPV infection is associated with CCCC and to elucidate the signaling pathways involved.

METHODS

We collected samples from 13 CCCC patients and collated the relevant clinicopathologic data. We then evaluated the presence of HPV types 16, 18, 31, 33, 35, 52, and 58 by broad-spectrum amplification by polymerase chain reaction and HPV types 39, 45, 51, 56, 59, and 68 by nested polymerase chain reaction assay that combines degenerate E6/E7 consensus primers and type-specific primers from extracted genomic DNA. Immunohistochemistry was used to analyze the expression of EGFR (epidermal growth factor receptor), HER2, PTEN (phosphatase and tensin homolog), phospho-AKT, phospho-mTOR (mammalian target of rapamycin), p16, and p53. EGFR and HER2 gene amplification was determined by fluorescence in situ hybridization.

RESULTS

Patients with stage IB CCCC had a better 3-year overall survival rate compared with those with advanced-stage cancer (100% vs 44%; P = 0.014). High-risk HPVs were not detected in any of the cases examined. EGFR immunostaining was observed in 9 (75%) of 12 patients, HER2 in 3 (25%) of 12, PTEN in 6 (50%) of 12, and phospho-AKT in 7 (58%) of 12, and phospho-mTOR in 6 (50%) of 12. EGFR amplification could not be detected, but HER2 amplification was identified in 1 of (12.5%) 8 cases.

CONCLUSIONS

Patients with stage I CCCC demonstrated good overall survival and rare recurrence. Clear cell carcinoma of the cervix is unrelated to high-risk HPV infection; hence, current vaccines will not prevent the incidence of CCCC. However, increased EGFR or HER2 expression or activation of AKT or mTOR was observed in all cases, indicating that inhibitors of tyrosine kinases or the AKT-mTOR pathway may be suitable treatment regimens for CCCC.

Cervical clear cell adenocarcinoma infected with human papillomavirus type 18 in an adolescent

BACKGROUND

Cervical clear cell carcinoma is one of the rare subtypes of cervical adenocarcinomas. Few cases of cervical clear cell carcinoma have been reported in adolescents.

CASE

We present here a case of a 14-year-old adolescent female diagnosed with a stage II cervical clear cell carcinoma. The patient had no sexual history or diethylstilbestrol-exposure in utero. Polymerase chain reaction identified in the tumor the presence of human papillomavirus type 18, a high-risk genotype for cervical cancer development. The ovaries were retained during surgery and the patient was still alive without recurrence after 9 years.

SUMMARY AND CONCLUSION

Positivity of HPV18 nucleic acids suggests an association between high risk HPV infection and cervical clear cell carcinoma in the case. Furthermore, in the treatment of young patients with cervical carcinoma, the risks associated with loss of ovarian function should be weighed against that of potential ovarian metastasis.

Detection and pathological value of papillomavirus DNA and p16INK4A and p53 protein expression in cervical intraepithelial neoplasia

The aim of the present study was to investigate human papillomavirus (HPV) infection and p16^INK4A and p53 protein expression, to evaluate their roles in the pathological diagnosis and grading for cervical intraepithelial neoplasia (CIN). The detection of HPV DNA and p16^INK4A and p53 protein expression were examined in a panel of clinical tissue samples using polymerase chain reaction or immunohistochemistry. In 104 cases, HPV16/18 DNA was identified in 49.0% and HPV6/11 DNA in 9.6% of cases. While in 203 cases, 74.4% positively expressed p16^INK4A and 47.3% positively expressed p53. The expression of p16^INK4A exhibited a significantly higher rate in the CIN I group than in the squamous metaplasia coupled with hyperplasia group (SMH; P<0.0001) and the CIN II–III group (P=0.005). A marked correlation was revealed between the band-like staining pattern of p16^INK4A and HPV16/18 infection. On the contrary, p53 expression was not found to significantly correlate with CIN grade or the HPV16/18 infection status. These results suggested that p16^INK4A expression correlates with a higher grade of CIN and may be used as a diagnostic marker to distinguish between CIN I and SMH, as well as between CIN I and CIN II–III.

The small splice variant of HPV16 E6, E6, reduces tumor formation in cervical carcinoma xenografts

High-risk types of human papillomavirus (HPV) cause nearly all cases of cervical cancer. The E6 oncoprotein is produced as a full-length variant (E6) as well as several shorter isoforms (E6). E6 inhibits certain oncogenic activities of E6, suggesting that it might play an anti-oncogenic role in vivo. To test this, we created E6-expressing SiHa (HPV(+)) and C33A (HPV(-)) cells, then examined the ability of both the parental and E6-expressing cells to form tumors in nude mice. We found that over-expression of E6 indeed decreased the growth of tumors derived from both SiHa and C33A cells, with the reduction greatest in tumors derived from E6-expressing SiHa cells. These findings point to multiple anti-oncogenic characteristics of E6, some of which likely involve down-regulation of the full-length isoform, and others that are independent of HPV. These data represent the first demonstration of biologically-relevant E6 activities distinct from those of the full-length isoform in vivo.

KCNH1 potassium channels are expressed in cervical cytologies from pregnant patients and are regulated by progesterone

Potassium voltage-gated channel, subfamily H (eag-related), member 1 (KCNH1) potassium channels are potential tumour markers and cancer therapeutic targets and are up-regulated by oestrogens and human papilloma virus (HPV) oncogenes. However, the role of KCNH1 in normal tissues is poorly understood, and its expression in pregnancy is unknown. We wondered whether KCNH1 channels are expressed in cervical cells from pregnant patients and whether progesterone (P4) regulates KCNH1. The association with HPV was also investigated. KCNH1 protein expression was studied by immunocytochemistry in liquid-based cervical cytologies; 93 samples were obtained from pregnant patients at different trimesters, and 15 samples were obtained from non-pregnant women (controls). The presence ofHPVwas studied by PCR with direct sequencing and nested multiplex PCR. HeLa cervical cancer cells were transfected with human progesterone receptor-B (PR-B) and treated with P4.KCNH1mRNA expression in these cultures was studied by real-time PCR. KCNH1 protein was detected in 100% of the pregnancy samples and in 26% of the controls. We found 18 pregnant patients infected with HPV and detected 14 types ofHPV. There was no association between the percentage of cells expressing KCNH1 and either the presence or type of HPV. P4induced KCNH1 mRNA and protein expression in cells transfected with human PR-B. No regulation of KCNH1 by P4was observed in non-transfected cells. We show for the first time the expression of an ion channel during human pregnancy at different trimesters and KCNH1 regulation by P4in human cells. These data raise a new research field for KCNH1 channels in human tissues.

Cervical intraepithelial neoplasia grade 2 or worse in Galicia, Spain: HPV 16 prevalence and vaccination impact

INTRODUCTION

The etiology of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) can influence the efficacy of Public Health preventive strategies. This study aimed to determine the high-risk papillomavirus (HR-HPV) prevalence in CIN2+ cases in unvaccinated women in Galicia (Spain), the expected impact of bivalent vaccination, and the distribution of HPV 16 in squamous lesions.

MATERIAL AND METHODS

Ninety-four histologically confirmed cases of CIN2+ (2009-2010) were retrospectively studied: 23 CIN2, 58 CIN3- squamous carcinoma in situ (CIN3-CIS), 5 adenocarcinoma in situ (AIS), and 8 invasive squamous cervical cancer (SCC). Linear Array HPV Genotyping Test (Roche Diagnostics, Mannheim, Germany) was performed on the cervical specimens. Bivalent vaccination impact was calculated, based on regional vaccination coverage data, local HR-HPV prevalence, and reported efficacy (direct and cross-protection) of the vaccine.

RESULTS

HR-HPV prevalence was 96.8%. The most frequent genotypes were HPV 16 (48.8-58.2%) and HPV 31 (9.3%-12.1%), considering single infections or single-multiple infections, respectively (hierarchical attribution). In squamous lesions, HPV 16 prevalence in women younger than 45 years of age increased in severe lesions (CIN3-CIS/SCC, OR 4.2), and was higher than in older women (OR 5.5). The vaccine could reduce the cumulative incidence of CIN2+ by 50.6% (direct protection), or by 62.7% (direct and cross-protection).

CONCLUSION

HPV vaccination could have a great impact in women younger than 45 years of age due to the high prevalence of HPV 16 in their lesions.

Global improvement in genotyping of human papillomavirus DNA: the 2011 HPV LabNet International Proficiency Study

Accurate and internationally comparable human papillomavirus (HPV) DNA genotyping is essential for HPV vaccine research and for HPV surveillance. The HPV Laboratory Network (LabNet) has designed international proficiency studies that can be issued regularly and in a reproducible manner. The 2011 HPV genotyping proficiency panel contained 43 coded samples composed of purified plasmids of 16 HPV types (HPV6, -11, -16, -18, -31, -33, -35, -39, -45, -51, -52, -56, -58, -59, -66, -68a, and -68b) and 3 extraction controls. Tests that detected 50 IU of HPV16 and HPV18 and 500 genome equivalents for the other 14 HPV types in both single and multiple infections were considered proficient. Ninety-six laboratories worldwide submitted 134 data sets. Twenty-five different HPV genotyping assay methods were used, including the Linear Array, line blot/INNO-LiPA, PapilloCheck, and PCR Luminex assays. The major oncogenic HPV types, HPV16 and HPV18, were proficiently detected in 97.0% (113/116) and 87.0% (103/118) of the data sets, respectively. In 2011, 51 data sets (39%) were 100% proficient for the detection of at least one HPV type, and 37 data sets (28%) were proficient for all 16 HPV types; this was an improvement over the panel results from the 2008 and 2010 studies, when <25 data sets (23% and 19% for 2008 and 2010, respectively) were fully proficient. The improvement was also evident for the 54 laboratories that had also participated in the previous proficiency studies. In conclusion, a continuing global proficiency program has documented worldwide improvement in the comparability and reliability of HPV genotyping assay performances.

Human papillomavirus genotyping and integration in ovarian cancer Saudi patients

Background

Human papillomavirus (HPV) is associated with different malignancies but its role in the pathogenesis of ovarian cancer is controversial. This study investigated the prevalence, genotyping and physical state of HPV in ovarian cancer Saudi patients.

Methods

Hundred formalin fixed paraffin embedded (FFPE) ovarian carcinoma tissues and their normal adjacent tissues (NAT) were included in the study. HPV was detected by nested polymerase chain reaction (PCR) using degenerated HPVL1 consensus primer pairs MY09/MY11 and GP5+/GP6 + to amplify a broad spectrum of HPV genotypes in a single reaction. The HPV positive samples were further genotyped using DNA sequencing. The physical state of the virus was identified using Amplification of Papillomavirus Oncogene Transcripts (APOT) assay in the samples positive for HPV16 and/or HPV18.

Results

High percentage of HPV (42%) was observed in ovarian carcinoma compared to 8% in the NAT. The high-risk HPV types 16, 18 and 45 were highly associated with the advanced stages of tumor, while low-risk types 6 and 11 were present in NAT. In malignant tissues, HPV-16 was the most predominant genotype followed by HPV-18 and -45. The percentage of viral integration into the host genome was significantly high (61.1%) compared to 38.9% episomal in HPV positive tumors tissues. In HPV18 genotype the percentage of viral integration was 54.5% compared to 45.5% episomal.

Conclusion

The high risk HPV genotypes in ovarian cancer may indicate its role in ovarian carcinogenesis. The HPV vaccination is highly recommended to reduce this type of cancer.

Molecular and evolutionary analysis of HPV16 E6 and E7 genes in Greek women

Human papillomavirus type 16 (HPV16) non-European variants have been associated with persistent infection and cervical cancer development, while the L83V variant of the E6 gene has been correlated with the progression of cervical malignancy. The present study investigated the presence of the HPV16 L83V variant in Greek women. Molecular evolutionary analysis of the HPV16 E6 and E7 oncogenes was conducted in order to estimate the evolution of the HPV16 genome in the Greek population. The E6 L83V variant was found in 78.2 % of high- and 64.28 % of low-grade specimens. Moreover, the prototype and E6 L83V variants were both prevalent in high- and low-grade malignancies in Greek women. Selective pressure analysis of the individual amino acid residues of HPV16 sequences from the Greek population indicates that codon 83 of the E6 protein, as well as codon 85 of the E7 protein, are undergoing positive selection. Novel sequence variations were recorded within the E6 and E7 genes in cervical samples, characterized as (T350G) European variants. However, no signal of intratypic recombination event was identified within the E6–E7 region. Molecular and evolutionary analyses of HPV16 genomes from distinct geographical locations might provide valuable information about viral evolution and oncogenecity.

Clinical and molecular characteristics of HNSCC patients with brain metastases: a retrospective study

Among the metastasis patterns of head and neck squamous cell carcinoma (HNSCC), intracranial spread is a rare but dreaded event. To date only very few cases have been reported and clinical and molecular data are sparse. We screened our archives for HNSCC patients from 1992 to 2005 who were diagnosed with brain metastases (BM). For retrospective analysis, all clinico-pathological data including disease-free survival (DFS), local progression-free survival (LPFS), and overall survival (OS) were compiled. Additionally, we assessed the mutational status of the TP53 gene and the prevalence of HPV serotypes by PCR and Sanger sequencing. Immunohistochemistry was applied to detect p16INK4A expression levels as surrogate marker for HPV infection. The prevalence rate of BM in our cohort comprising 193 patients with advanced HNSCC was 5.7%. Of 11 patients with BM, 3 were female and 9 were male. Seven of the primary tumors were of oropharyngeal origin (OPSCC). LPFS of the cohort was 11.8 months, DFS was 12.1 months and OS was 36.0 months. After the diagnosis of BM, survival was 10.5 months. Five tumors showed a mutation in the TP53 gene, while five of the seven OPSCC tumors had a positive HPV status displaying infection with serotype 16 in all cases. Compared with patients who harbored TP53wt/HPV-positive tumors, patients with TP53 mutations showed a poor prognosis. Compared with the whole cohort, the interval between diagnosis of the primary and the detection of BM was prolonged in the HPV-infected OPSCC subgroup (26.4 vs. 45.6 months). The prognosis of HNSCC patients with BM is poor. In our cohort, most tumors were OPSCC with the majority being HPV positive. Our study points toward a putatively unusual metastatic behavior of HPV-positive OPSCC.

Classical molecular tests using urine samples as a potential screening tool for human papillomavirus detection in human immunodeficiency virus-infected women

Human papillomavirus (HPV) is the main risk factor associated with the development of cervical cancer (CC); however, there are other factors, such as immunosuppression caused by the human immunodeficiency virus (HIV), that favor progression of the illness. This study was thus aimed at evaluating the functionality of classical PCR-based molecular tests for the generic identification of HPV DNA (GP5+/GP6+, MY09/MY11, and pU1M/2R primers, individually or in combination) using cervical and urine samples from 194 HIV-positive women. Infected samples were tested with type-specific primers for six high-risk types (HPV-16, -18, -31, -33, -45, and -58) and two low-risk types (HPV-6 and -11). HPV infection prevalence rates were 70.1% for the cervical samples and 63.9% for the urine samples. HPV-16 was the most prevalent viral type in the cervical and urine samples, with higher rates of multiple infections than single infections detected in such samples. HPV DNA detection by PCR (mainly with the pU1M/2R primer set) in urine samples was positively associated with abnormal cytological findings (atypical squamous cells of undetermined significance/squamous intraepithelial lesions [ASCUS/SIL]). It was determined that the operative characteristics for detection of cytological abnormalities were similar for cervical and urine samples. This suggested using PCR for the detection of HPV DNA in urine samples as a potential screening strategy for CC prevention in future prevention and control programs along with currently implemented strategies for reducing the impact of the disease, i.e., urine samples are economical, are easy to collect, have wide acceptability among women, and have operative characteristics similar to those of cervical samples.

Human papillomavirus infection and spontaneous abortion: a case-control study performed in Mexico

OBJECTIVE

To investigate if HPV cervical infection is associated with spontaneous abortion in a Mexican population.

STUDY DESIGN

Case control study including 281 women from two Social Security Hospitals in Merida, Mexico. Cases were women with spontaneous abortion attending for curettage, and controls were pregnant women at term who attended for delivery. HPV molecular detection and typing of HPV 16, 18, 58 and 6/11 was performed on cervical samples, and TORCH serology IgM tests (against T. gondii, CMV, HSV) were performed on cases. Data were analyzed using Chi square, odds ratio and linear regression tests.

RESULTS

HPV global prevalence was 19.8% (24.4% in cases and 15.2% in controls). HPV types 16 and 58 were the most frequently detected in both groups. Multiple HPV types concurrent infection were found in 31.4% of typified samples. Amongst cases 27.3% of HPV positive women reported at least one previous pregnancy loss; compared to 17.43% amongst HPV negative women. Nevertheless, HPV was not significantly associated with spontaneous or to repetitive abortion. Cases were 60.2% positive to any TORCH agent, although it was not significantly associated to referred miscarriage history. Spontaneous abortion was associated to a previous pregnancy loss and to women's age older than 35 years old. HPV infection was significantly associated to alcohol intake before pregnancy and to multiple sexual partners.

CONCLUSION

HPV cervical infection was not associated with spontaneous abortion. HPV in spontaneous abortion and other adverse pregnancy outcomes merits further study.

Nucleotide polymorphisms of the human papillomavirus 16 E1 gene

The E1 ORF is one of the most conserved regions in the human papillomavirus (HPV) genome. The complete E1 gene of the HPV16 genome was amplified with four overlapping primer sets in 16 high-grade (CIN II, III) and 13 low-grade cervical (CIN I) intraepithelial neoplasias as well as in one cervical cancer case. Sequence analysis of the E6 and E7 genes was also carried out in the same cervical samples in order to confirm the association between nucleotide sequence variations in the HPV16 E1 ORF and HPV16 variant lineages. Analysis of the E1 ORF revealed 27 nucleotide changes, and these changes were correlated with those found in HPV16 Asian American and African type II variants. Of these nucleotide variations, A1668G, G2073A, T2169C, T2189C, A2453T, C2454T, A2587T and G2650A were identified only in high-grade dysplasia cases. A phylogenetic tree of the E1 ORF and nucleotide sequence analysis of the E1, E6 and E7 genes revealed that intratypic nucleotide sequence polymorphisms located in the E1 ORF can be used to identify the major phylogenetic branch to which a HPV16 genome belongs. Moreover, amplification of the E1 ORF revealed a disruption between nucleotides 878 and 1523 in five high- and two low-grade cervical cases, indicating that integration of HPV DNA occurs at an early stage of viral infection.

HPV involvement in OSCC: Correlation of PCR results with light microscopic features

OBJECTIVES

The study evaluated pathognomic histopathological features with the help of light microscopy for detecting the integration of human papillomavirus (HPV) (type 16 and 18) in oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

Forty-five histopathologically diagnosed cases of OSCC were evaluated for the presence of E6/E7 protein of HPV (16 + 18) with the help of nested multiplex polymerase chain reaction. Both HPV-positive and -negative cases were evaluated for four histological features: Koilocytes, dyskeratosis, invasion, and alteration of collagen.

RESULTS

Fischer's exact test showed significant difference (P < 0.01%) for the presence of koilocytes and dyskeratosis, whereas no difference was observed for invasion and alteration in collagen between HPV-positive and -negative OSCC.

CONCLUSION

The presence of koilocytes and dyskeratosis at light microscopic level can be used as a marker for the presence of HPV (type 16 and 18) in OSCC.

HPV-related methylation signature predicts survival in oropharyngeal squamous cell carcinomas

High-risk types of human papilloma virus (HPV) are increasingly associated with oropharyngeal squamous cell carcinoma (OPSCC). Strikingly, patients with HPV-positive OPSCC are highly curable with ionizing radiation and have better survival compared with HPV-negative patients, but the underlying molecular mechanisms remain poorly understood. We applied an array-based approach to monitor global changes in CpG island hypermethylation between HPV-negative and HPV-positive OPSCCs and identified a specific pattern of differentially methylated regions that critically depends on the presence of viral transcripts. HPV-related alterations were confirmed for the majority of candidate gene promoters by mass spectrometric, quantitative methylation analysis. There was a significant inverse correlation between promoter hypermethylation of ALDH1A2, OSR2, GATA4, GRIA4, and IRX4 and transcript levels. Interestingly, Kaplan-Meier analysis revealed that a combined promoter methylation pattern of low methylation levels in ALDH1A2 and OSR2 promoters and high methylation levels in GATA4, GRIA4, and IRX4 promoters was significantly correlated with improved survival in 3 independent patient cohorts. ALDH1A2 protein levels, determined by immunohistochemistry on tissue microarrays, confirmed the association with clinical outcome. In summary, our study highlights specific alterations in global gene promoter methylation in HPV-driven OPSCCs and identifies a signature that predicts the clinical outcome in OPSCCs.

Presence of human papilloma virus in a series of breast carcinoma from Argentina

Background

The etiology and the molecular mechanisms related to breast carcinogenesis remain poorly understood. Some recent reports have examined the role of Human Papillomavirus (HPV) in this disease. The purpose of this study was to determine the prevalence of HPV in breast cancer.

Methods

Sixty one fresh frozen breast cancers samples were analyzed. Samples were tested for HPV by PCR, and products were automatically sequenced. Findings were correlated with clinical and pathological characteristics.

Results

The HPV DNA prevalence in the breast cancer samples was 26% (16/61). Clinical parameters were not statistically associated with HPV presence (p>0.05 χ² test). Sequence analysis in a subgroup of cases indicates the prevalence of low risk HPV11, followed by high risk HPV16. We found no HPV transcriptional activity.

Conclusion

The present study demonstrated for the first time in Argentina the presence of HPV in a proportion of the malignant breast tissues. This finding suggests that HPV may have a biological significance in breast carcinogenesis.

Frequency and genotype distribution of multiple human papillomavirus infections in cancer of the head and neck in a Mexican population

OBJECTIVE

The aim of this study was to determine the frequency and genotype distribution of single and multiple human papillomavirus (HPV) infections in head and neck squamous cell carcinomas (HNSCCs) in a Mexican population and to assess their associations with smoking and drinking habits and clinicopathologic characteristics.

STUDY DESIGN

A cross-sectional study was performed on a sample of patients diagnosed with HNSCCs. Tumor DNA was amplified using polymerase chain reaction with HPV consensus and multiplex primers. The associations among HPV status, survival, and clinical characteristics were analyzed.

RESULTS

Sixteen of the 43 HNSCCs were HPV positive. HPV16 was the most prevalent type, with single infections present in 5 cases, whereas another 5 cases were combined with HPV56 infection. There was a significant association between HPV infection and oropharyngeal cancers. HPV positivity was associated with overall survival at a nearly significant P level of 0.06.

CONCLUSIONS

Our data support the importance of HPV infection in oropharyngeal cancer, with a trend toward higher survival in HPV-positive cases.

Human papillomavirus detection from human immunodeficiency virus-infected Colombian women's paired urine and cervical samples

Infection, coinfection and type-specific human papillomavirus (HPV) distribution was evaluated in human immunodeficiency virus (HIV)-positive women from paired cervical and urine samples. Paired cervical and urine samples (n = 204) were taken from HIV-positive women for identifying HPV-DNA presence by using polymerase chain reaction (PCR) with three generic primer sets (GP5+/6+, MY09/11 and pU1M/2R). HPV-positive samples were typed for six high-risk HPV (HR-HPV) (HPV-16, -18, -31, -33, -45 and -58) and two low-risk (LR-HPV) (HPV-6/11) types. Agreement between paired sample results and diagnostic performance was evaluated. HPV infection prevalence was 70.6% in cervical and 63.2% in urine samples. HPV-16 was the most prevalent HPV type in both types of sample (66.7% in cervical samples and 62.0% in urine) followed by HPV-31(47.2%) in cervical samples and HPV-58 (35.7%) in urine samples. There was 55.4% coinfection (infection by more than one type of HPV) in cervical samples and 40.2% in urine samples. Abnormal Papanicolau smears were observed in 25.3% of the women, presenting significant association with HPV-DNA being identified in urine samples. There was poor agreement of cervical and urine sample results in generic and type-specific detection of HPV. Urine samples provided the best diagnosis when taking cytological findings as reference. In conclusion including urine samples could be a good strategy for ensuring adherence to screening programs aimed at reducing the impact of cervical cancer, since this sample is easy to obtain and showed good diagnostic performance.

High-risk human papillomavirus genotype detection by electrochemical DNA chip method

High-risk human papillomavirus (HPV) genotypes are the major cause of cervical cancer. Hence, HPV genotype detection is a helpful preventive measure to combat cervical cancer. Recently, several HPV detection methods have been developed, each with different sensitivities and specificities. The objective of this study was to compare HPV high risk genotype detection by an electrochemical DNA chip system, a line probe assay (INNO- LiPA) and sequencing of the L1, E1 regions. A total of 361 cervical smears with different cytological findings were subjected to polymerase chain reaction-sequencing and electrochemical DNA chip assessment. Multiple infections were found in 21.9% (79/361) of the specimens, most prevalently in 20-29-year olds while the highest prevalence of HPV infection was found in the 30-39-year age group. The most prevalent genotype was HPV 16 at 28.2% (138/489) followed by HPV 52 at 9.6% (47/489), with the other types occurring at less than 9.0%. The electrochemical DNA chip results were compared with INNO-LiPA and sequencing (E1 and L1 regions) based on random selection of 273 specimens. The results obtained by the three methods were in agreement except for three cases. Direct sequencing detected only one predominant genotype including low risk HPV genotypes. INNO-LiPA identified multiple infections with various specific genotypes including some unclassified-risk genotypes. The electrochemical DNA chip was highly accurate, suitable for detection of single and multiple infections, allowed rapid detection, was less time-consuming and was easier to perform when compared with the other methods. It is concluded that for clinical and epidemiological studies, all genotyping methods are perfectly suitable and provide comparable results.

Case-control study of HLA-G promoter methylation status, HPV infection and cervical neoplasia in Curitiba, Brazil: a pilot analysis

Background

The causal association between persistent human papillomavirus (HPV) infection and cervical cancer has been established, but the mechanisms that favor HPV persistence in cervical cells are still unknown. The diminished capability of the immune system to control and resolve HPV infection is one of several hypotheses. The tolerogenic protein HLA-G has shown aberrant expression in a variety of cancers, which has been suggested as a mechanism for tumor escape from immunosurveillance. In the present study we evaluate the role of epigenetic modification (promoter de-methylation) of the HLA-G gene on susceptibility to HPV infection and development of high-grade cervical lesions.

Methods

A case–control study was carried out in Curitiba, Brazil, between February and June 2010. A total of 789 women aged 15–47 years were recruited: 510 controls with normal cervical cytology, and 279 cases with histologically confirmed cervical intraepithelial neoplasia grade 2 (CIN2, N = 150) or grade 3 (CIN3, N = 129). All women were administered a questionnaire by interview, which collected information on demographic and lifestyle factors, and a cervical sample was collected. HPV DNA detection was performed by GP5+/GP6+ primer-mediated PCR. HPV-positive samples were genotyped by multiplex PCR. A pilot analysis of HLA-G promoter methylation was carried out in a subset of the study population (96 cases and 76 controls) by pyrosequencing. HLA-G methylation and HPV infection status of cases and controls were compared, and confounding factors were computed by t Student and non-parametric Wilcoxon tests. Comparison of HLA-G methylation between cases and controls was assessed by the Bonferroni correction. The association of HLA-G methylation with CIN2/3 was evaluated by logistic regression.

Results

HPV prevalence was 19.6% in controls and 94.3% in CIN2/3 cases. HPV16, 31, 33, 35 and 18 were the most prevalent types. Methylation analysis of seven CpGs in the HLA-G promoter did not reveal any spontaneous de-methylation events in CIN2/3 cases (mean proportion of methylation: 75.8%) with respect to controls (mean 73.7%; odds ratio 1.01, 95% confidence interval 0.96, 1.07).

Conclusions

This study did not support the hypothesis that spontaneous de-methylation events in the HLA-G promoter play a primary role in promoting escape from immunosurveillance in the development of precancerous cervical lesions.

Identification of novel E6-E7 sequence variants of human papillomavirus 16

The rate of evolution of the human papillomavirus 16 (HPV16) genome is low. However, the ability of the E6 oncoprotein to interact with distinct p53 variants causes selective pressure on the E6 gene. In addition, intratypic recombination events in the HPV16 E6 and E7 genes have been characterized as extraordinary phenomena during the evolutionary history of virus. In the present study, we identified two new sequence variants through nucleotide analysis of the E6-E7 region of the HPV16 genome. Maximum-likelihood and empirical Bayesian methods were used in order to identify positive selection at particular residues of the E6 and E7 genes. Using the single recombination breakpoint (SBP) method, we found evidence of recombination events in the E6 ORF. Nucleotide sequence analysis showed that the new sequence variants are phylogenetically distant from the other members of the population. Our results indicate that new evolutionary intermediates of HPV16 might be formed either though positive selective pressure or through recombination events by multiple infections with distinct HPV16 variants.

Lack of evidence for an association between seminoma and human papillomavirus infection using GP5+/GP6+ consensus primers

Testicular germ cell tumors account for about 1% of all cancers. The incidence of these tumors is increasing and they represent the most common solid malignancies of young men aged 15-40 years with seminoma being one of the most common histotype. Pathogenesis of testicular germ cell tumors remains unknown and, although cryptorchidism is considered the main risk factor, there is evidence of an association with environmental and genetic risk factors. Human papillomaviruses (HPV) are a family of DNA viruses and represent a major risk factor for cervical cancer. In addition, they have been associated with other human non-malignant and malignant diseases, including breast and head and neck cancer. HPV sequences have been detected throughout the male lower genitourinary tract as well as in seminal fluid and an increased testicular tumorigenesis has been reported in HPV transgenic mice. Aim of this study was to evaluate the potential involvement of HPV in human testicular tumorigenesis. Real-time PCR employing GP5+/GP6+ consensus HPV primers was used to examine the presence of HPV sequences in a subset of human seminoma (n = 61) and normal testicles (n = 23). None of the specimens tested displayed the presence of HPV DNA. These findings do not support an association between HPV and human seminoma and warrant further studies to assess definitively the role of these viruses in human testicular tumorigenesis.