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Concept: Human papillomavirus

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BackgroundThe American Cancer Society (ACS), the Centers for Disease Control and Prevention (CDC), the National Cancer Institute (NCI), and the North American Association of Central Cancer Registries (NAACCR) collaborate annually to provide updates on cancer incidence and death rates and trends in these outcomes for the United States. This year’s report includes incidence trends for human papillomavirus (HPV)-associated cancers and HPV vaccination (recommended for adolescents aged 11-12 years).MethodsData on cancer incidence were obtained from the CDC, NCI, and NAACCR, and data on mortality were obtained from the CDC. Long- (1975/1992-2009) and short-term (2000-2009) trends in age-standardized incidence and death rates for all cancers combined and for the leading cancers among men and among women were examined by joinpoint analysis. Prevalence of HPV vaccination coverage during 2008 and 2010 and of Papanicolaou (Pap) testing during 2010 were obtained from national surveys.ResultsDeath rates continued to decline for all cancers combined for men and women of all major racial and ethnic groups and for most major cancer sites; rates for both sexes combined decreased by 1.5% per year from 2000 to 2009. Overall incidence rates decreased in men but stabilized in women. Incidence rates increased for two HPV-associated cancers (oropharynx, anus) and some cancers not associated with HPV (eg, liver, kidney, thyroid). Nationally, 32.0% (95% confidence interval [CI] = 30.3% to 33.6%) of girls aged 13 to 17 years in 2010 had received three doses of the HPV vaccine, and coverage was statistically significantly lower among the uninsured (14.1%, 95% CI = 9.4% to 20.6%) and in some Southern states (eg, 20.0% in Alabama [95% CI = 13.9% to 27.9%] and Mississippi [95% CI = 13.8% to 28.2%]), where cervical cancer rates were highest and recent Pap testing prevalence was the lowest.ConclusionsThe overall trends in declining cancer death rates continue. However, increases in incidence rates for some HPV-associated cancers and low vaccination coverage among adolescents underscore the need for additional prevention efforts for HPV-associated cancers, including efforts to increase vaccination coverage.

Concepts: American Cancer Society, Papillomavirus, Gardasil, Cervical cancer, Anal cancer, Cancer, HPV vaccine, Human papillomavirus

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Cervical cancer is one of the leading causes of cancer death in women worldwide. The causative agents of cervical cancers, high-risk human papillomaviruses (HPVs), cause cancer through the action of two oncoproteins, E6 and E7. The E6 oncoprotein cooperates with an E3 ubiquitin ligase (UBE3A) to target the p53 tumour suppressor and important polarity and junctional PDZ proteins for proteasomal degradation, activities that are believed to contribute towards malignancy. However, the causative link between degradation of PDZ proteins and E6-mediated malignancy is largely unknown. We have developed an in vivo model of HPV E6-mediated cellular transformation using the genetic model organism, Drosophila melanogaster. Co-expression of E6 and human UBE3A in wing and eye epithelia results in severe morphological abnormalities. Furthermore, E6, via its PDZ-binding motif and in cooperation with UBE3A, targets a suite of PDZ proteins that are conserved in human and Drosophila, including Magi, Dlg and Scribble. Similar to human epithelia, Drosophila Magi is a major degradation target. Magi overexpression rescues the cellular abnormalities caused by E6+UBE3A coexpression and this activity of Magi is PDZ domain-dependent. Drosophila p53 was not targeted by E6+UBE3A, and E6+UBE3A activity alone is not sufficient to induce tumorigenesis, which only occurs when E6+UBE3A are expressed in conjunction with activated/oncogenic forms of Ras or Notch. Finally, through a genetic screen we have identified the insulin receptor signaling pathway as being required for E6+UBE3A induced hyperplasia. Our results suggest a highly conserved mechanism of HPV E6 mediated cellular transformation, and establish a powerful genetic model to identify and understand the cellular mechanisms that underlie HPV E6-induced malignancy.

Concepts: Oncology, Drosophila, Proteasome, Cervical cancer, Model organism, Drosophila melanogaster, Human papillomavirus, Cancer

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Purpose: The purpose of this study was to assess ordering of human papillomavirus (HPV) testing for normal cervical cytology among low-risk women aged 30 to 65 years.

Concepts: Harald zur Hausen, Cervarix, Cervical intraepithelial neoplasia, Gardasil, HPV vaccine, Papillomavirus, Cervical cancer, Human papillomavirus

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Tumorigenesis is a clonal evolution process that is initiated from single cells within otherwise histologically normal tissue. It is unclear how single, sporadic mutant cells that have sustained oncogenic alterations evolve within a tightly regulated tissue environment. Here we investigated the effects of inducing oncogene expression in single cells in organotypic mammary acini as a model to elucidate the processes by which oncogenic alterations initiate clonal progression from organized epithelial environments. Sporadic cells induced to overexpress oncogenes that specifically perturb cell-cycle checkpoints (for example, E7 from human papilloma virus 16, and cyclin D1), deregulate Myc transcription or activate AKT signalling remained quiescent within growth-arrested acini. By contrast, single cells that overexpress ERBB2 initiated a cellular cascade involving cell translocation from the epithelial layer, as well as luminal outgrowth that is characteristic of neoplastic progression in early-stage epithelial tumours. In addition, ERBB2-mediated cell translocation to the lumen was found to depend on extracellular-regulated kinase and matrix metalloproteinase activities, and genetic alterations that perturb local cell-matrix adhesion drove cell translocation. We also provide evidence that luminal cell translocation may drive clonal selection by promoting either the death or the expansion of quiescent oncogene-expressing cells, depending on whether the pre-existing alterations allow anchorage-independent survival and growth. Our data show that the initial outgrowth of single oncogene-expressing cells from organized epithelial structures is a highly regulated process, and we propose that a cell translocation mechanism allows sporadic mutant cells to evade suppressive micro-environments and elicits clonal selection for survival and proliferative expansion outside the native niches of these cells.

Concepts: Transcription factor, Chromosome, Gene, Oncogene, Gene expression, Human papillomavirus, Genetics, Cancer

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BACKGROUND: The human papillomavirus (HPV) vaccine offers an opportunity to reduce health inequalities associated with cervical cancer provided the vaccine is delivered equitably at population level.Method We reviewed evidence of inequalities in HPV vaccine uptake in young women after undertaking a comprehensive search of databases from inception to March 2012. Studies that compared HPV vaccination initiation and/or completion by at least one ethnicity or socioeconomic-related variable in adolescent young women were included. There were no language restrictions. Data were extracted by two reviewers and pooled in a meta-analysis using a random-effects model; sub-analyses and meta-regression were undertaken to investigate sources of heterogeneity. RESULTS: In all, 29 publications related to 27 studies were included in the review. Black young women were less likely to initiate HPV vaccination compared with White young women (combined OR: 0.89, 95% CI: 0.82-0.97). In the USA, young women without healthcare insurance were less likely to initiate (combined OR: 0.56, 95% CI: 0.40-0.78). There was no strong evidence that lower family income (combined OR: 1.16, 95% CI: 1.00-1.34) or lower parental education (combined OR 1.06, 95% CI: 0.92-1.22) influenced HPV vaccination initiation. CONCLUSIONS: We found strong evidence for differences in HPV vaccination initiation by ethnicity and healthcare coverage, but did not find a strong association with parental education or family income variables. The majority of studies originated from the USA. Population-based studies reporting both initiation and completion of the HPV vaccination programme are required to establish patterns of uptake in different healthcare contexts.

Concepts: Anal cancer, Papillomavirus, Gardasil, Cervical cancer, Human papillomavirus, HPV vaccine

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BACKGROUND: Oropharyngeal cancers are increasingly associated with human papillomavirus (HPV). Little is known about the experience of patients receiving this diagnosis. METHODS: Semistructured interviews were conducted with ten survivors of HPV-related oropharyngeal cancer. The interviews were transcribed, and recurring themes were identified. RESULTS: Physicians were a trusted source of information regarding HPV. Framing the diagnosis in terms of prognosis resonated with patients. The uncertainty about transmission, latency, and communicability colored the dialogue about HPV. Despite some understanding of prevalence and transmission, patients worried about their partner’s risk. Patients sought information about HPV on the Internet, but it was not easily navigable. Emotional reactions to the diagnosis remained mostly cancer-centric rather than HPV-centric. A patient-education handout was developed in response to patient questions. CONCLUSIONS: Additional educational resources explaining the facts about HPV in HNSCC in a consistent way including content of highest priority to patients may improve understanding of HPV. © 2012 Wiley Periodicals, Inc. Head Neck, 2012.

Concepts: Anal cancer, Head and neck, Physician, Head and neck anatomy, Lung cancer, Head and neck cancer, Cancer, Human papillomavirus

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OBJECTIVE: Human papillomavirus (HPV) infections remain a leading cause of mortality worldwide. In the U.S. strategies via screening and vaccination prevent HPV-associated cervical neoplasms, but consumes immense healthcare costs. The spice component curcumin has potent anticancer and antiviral properties, which have been difficult to harness as a treatment, due to its poor systemic bioavailability. This project tests the possibility of developing a curcumin-based therapy for cervical cancer. METHODS: Using four HPV(+) cervical cancer cell lines and normal fibroblasts we first tested the selectivity and potency of curcumin in eliminating HPV(+) cells. Subsequently, we developed a curcumin-based cervical cream and tested its efficacy in eliminating apposed HPV(+) cells and also its possible side effects on the vaginal epithelium of healthy mice. RESULTS: Curcumin selectively eliminates a variety of HPV(+) cervical cancer cells (HeLa, ME-180, SiHa, and SW756), suppresses the transforming antigen E6, dramatically inhibits the expression of the pro-cancer protein epidermal growth factor receptor (EGFR), and concomitantly induces p53. Additionally, Vacurin, a uniform colloidal solution of curcumin in a clinically used amphipathic vaginal cream, eliminates apposed HeLa cells while suppressing the expression of EGFR. In mice, daily intravaginal application of Vacurin for three weeks produced no change in body weight and when the mice were sacrificed, the vaginal tract epithelium showed no Vacurin-evoked adverse effects. CONCLUSION: We have developed a curcumin-based vaginal cream, which effectively eradicates HPV(+) cancer cells and does not affect non-cancerous tissue. Our preclinical data support a novel approach for the treatment of cervical HPV infection.

Concepts: Epidermal growth factor receptor, Lung cancer, P53, HPV vaccine, Cervical cancer, Human papillomavirus, Cancer, Immune system

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BACKGROUND: Clinical studies have demonstrated that HPV induced tumors constitute a specific subclass of cancer with a better response to radiation treatment. The purpose of this study was to investigate meaning of viral E2-gene for radiosensitivity. METHODS: W12 cells contain episomal HPV 16 genomes, whereas S12 cells, which derive from the W12 line, contain HPV DNA as integrated copies. Clonogenic survival was analyzed using 96-well in vitro test. Using flow cytometry cell cycle analyses were performed. Expression of pRb and p53 were analyzed using intracellular staining. RESULTS: W12 cells (intact E2 gene) showed a lower survival fraction than S12 cells. W12 cells developed a G2/M block 24 h after irradiation with 2 Gy whereas S12 showed no G2/M bloc. After irradiation S12 cells developed polyploidy and pRb-positive cells decreased. W12 cells showed no change of pRb-positive cells. CONCLUSIONS: Depending on E2 gene status differences in cell cycle regulation might cause radioresistance. The E2/E7/pRb pathway seems to influence HPV-induced radiosensitivity. Our experiments demonstrated an effect of HPV on radiosensitivity of cervical keratinocytes via viral transcription regulator E2 pathway.

Concepts: Genetics, Chromosome, Cell nucleus, Human papillomavirus, Gene, DNA, Cancer, Gene expression

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Cervical cancer is the third most common cancer affecting women worldwide and it is an important cause of death, especially in developing countries. Cervical cancer is caused by human papillomavirus (HPV) and can be prevented by HPV vaccine. The challenge is to expand vaccine availability to countries where it is most needed. In 2008 Peru’s Ministry of Health implemented a demonstration project involving 5(th) grade girls in primary schools in the Piura region. We designed and conducted a qualitative study of the decision-making process among parents of girls, and developed a conceptual model describing the process of HPV vaccine acceptance.

Concepts: Cervarix, Cervical intraepithelial neoplasia, Anal cancer, Papillomavirus, Gardasil, Cervical cancer, HPV vaccine, Human papillomavirus

169

SELDI-TOF mass spectrometer’s compact size and automated, high throughput design have been attractive to clinical researchers, and the platform has seen steady-use in biomarker studies. Despite new algorithms and preprocessing pipelines that have been developed to address reproducibility issues, visual inspection of the results of SELDI spectra preprocessing by the best algorithms still shows miscalled peaks and systematic sources of error. This suggests that there continues to be problems with SELDI preprocessing. In this work, we study the preprocessing of SELDI in detail and introduce improvements. While many algorithms, including the vendor supplied software, can identify peak clusters of specific mass (or m/z) in groups of spectra with high specificity and low false discover rate (FDR), the algorithms tend to underperform estimating the exact prevalence and intensity of peaks in those clusters. Thus group differences that at first appear very strong are shown, after careful and laborious hand inspection of the spectra, to be less than significant. Here we introduce a wavelet/neural network based algorithm which mimics what a team of expert, human users would call for peaks in each of several hundred spectra in a typical SELDI clinical study. The wavelet denoising part of the algorithm optimally smoothes the signal in each spectrum according to an improved suite of signal processing algorithms previously reported (the LibSELDI toolbox under development). The neural network part of the algorithm combines those results with the raw signal and a training dataset of expertly called peaks, to call peaks in a test set of spectra with approximately 95% accuracy. The new method was applied to data collected from a study of cervical mucus for the early detection of cervical cancer in HPV infected women. The method shows promise in addressing the ongoing SELDI reproducibility issues.

Concepts: Clinical research, Mass spectrometry software, Mass-to-charge ratio, Cervical cancer, Human papillomavirus, Ion source, Soft laser desorption, Mass spectrometry