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115 result(s) for "Clifford, Gary M."
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Human papillomavirus types from infection to cancer in the anus, according to sex and HIV status: a systematic review and meta-analysis
Data on carcinogenicity of human papillomavirus (HPV) types in the anus are needed to inform anal cancer prevention through vaccination and screening. This is particularly the case for people infected with HIV, who are at an increased risk of anal cancer. We did a systematic review of studies published from January, 1986, to July, 2017, in MEDLINE, Embase, and the Cochrane Library on anal HPV infection, without any language restrictions. Eligible studies reported type-specific HPV prevalence by strata of cytopathological or histopathological anal diagnosis, sex, and HIV status. Data requests were made to authors when necessary. We did a meta-analysis of type-specific HPV prevalence across the full spectrum of anal diagnoses, from normal cytology to anal cancer. We assessed the main outcome of type-specific HPV prevalence ratios [PR], calculated across strata of anal diagnoses, gender, or HIV status, by use of generalised linear models. 95 studies were identified from the search, published between 1992–2017, from which 18 646 individuals fulfilled the criteria for inclusion in the analyses: 8534 people with normal cytology, 5730 with low-grade lesions, 2024 with high-grade lesions, and 2358 with anal cancer. HPV prevalence varied in normal cytology from 42% in HIV-negative women to 76% in HIV-positive men and, for each diagnosis, was higher in individuals who were HIV positive than those who were HIV negative. HPV16 positivity increased with diagnosis severity, being the only HPV type accounting for more HPV infection in anal cancer than normal cytology, both in individuals who were HIV negative (PR 5·0, 95% CI 3·8–6·6, p<0·0001) and those who were HIV positive (2·3, 1·9–2·7, p<0·0001). HPV16 positivity increased even between high-grade lesions and anal cancer, whereas other high-risk HPV types accounted for high proportions of low-grade or high-grade lesions but their prevalence decreased in anal cancer. However, HPV16 was less frequent in HIV-positive than HIV-negative anal cancer, both in men (PR 0·8, 95% CI 0·7–0·9, p<0·0001) and women (0·8, 0·6–1·0, p=0·063), and in HIV-positive versus HIV-negative high-grade lesions in women (0·6, 0·5–0·9, p=0·0077). Type-specific attribution of the non-HPV16 fraction of HIV-positive anal cancer is hindered by a high prevalence of multiple HPV infections. HPV16 is by far the most carcinogenic HPV type in the anus, with enrichment of HPV16 even from high-grade lesions to anal cancer, both in individuals who are HIV negative and those who are HIV positive. Nevertheless, the fraction of anal cancer attributable to HPV16 is smaller in the HIV-positive population. International Agency for Research on Cancer.
Carcinogenicity of Human Papillomavirus (HPV) Types in HIV-Positive Women: A Meta-Analysis From HPV Infection to Cervical Cancer
Background. Data on the relative carcinogenic potential of human papillomavirus (HPV) types among women infected with human immunodeficiency virus (HIV) (WHIV) are needed to inform prevention programs for this population. Methods. A systematic literature review and meta-analysis of high-risk HPV-type distribution in 19 883 HIV-positive women was performed. The women, from 86 studies worldwide, included 11 739 with normal cytological findings; 1784 with atypical squamous cells of undetermined significance (ASCUS); 2173 with low-grade and 1282 with high-grade squamous intraepithelial lesions (HSILs) diagnosed cytologically; 1198 with cervical intraepithelial neoplasia grade 1 (CIN1), 456 with CIN2, and 455 with CIN3 diagnosed histologically; and 796 with invasive cervical cancers (ICCs). A large proportion of WHIV, and almost all with ICCs, were from Africa. Results. In Africa, HPV 16 accounted for 13% of HPV-positive WHIV with normal cytological findings, but this proportion increased through ASCUS, low-grade squamous intraepithelial lesions, CIN1, and CIN2 (18%–25%), up to 41%–47% for CIN3 and ICCs. Only HPV 16, HPV 18, and HPV 45 accounted for a greater proportion of HPV infections in ICCs compared with normal cytological findings (ICC:normal ratios, 3.68, 2.47, and 2.55, respectively). Other high-risk types accounted for important proportions of low- and/or high-grade lesions, but their contribution dropped in ICCs, with ICC:normal ratios in Africa ranging from 0.79 for HPV 33 down to 0.38 for HPV 56. Findings for HPV 16 and HPV 18 in Europe/North America, Asia, and Latin America were compatible with those from Africa. Conclusions. HPV 16 and HPV 18 in particular, but also HPV 45, at least in Africa, warrant special attention in WHIV. Broad consistency of findings with those in HIV-uninfected population would suggest that the risk stratification offered by partial HPV genotyping tests also have relevance for HIV-positive women.
Niche adaptation and viral transmission of human papillomaviruses from archaic hominins to modern humans
Recent discoveries on the origins of modern humans from multiple archaic hominin populations and the diversity of human papillomaviruses (HPVs) suggest a complex scenario of virus-host evolution. To evaluate the origin of HPV pathogenesis, we estimated the phylogeny, timing, and dispersal of HPV16 variants using a Bayesian Markov Chain Monte Carlo framework. To increase precision, we identified and characterized non-human primate papillomaviruses from New and Old World monkeys to set molecular clock models. We demonstrate specific host niche adaptation of primate papillomaviruses with subsequent coevolution with their primate hosts for at least 40 million years. Analyses of 212 HPV16 complete genomes and 3582 partial sequences estimated ancient divergence of HPV16 variants (between A and BCD lineages) from their most recent common ancestors around half a million years ago, roughly coinciding with the timing of the split between archaic Neanderthals and modern Homo sapiens, and nearly three times longer than divergence times of modern Homo sapiens. HPV16 A lineage variants were significantly underrepresented in present African populations, whereas the A sublineages were highly prevalent in European (A1-3) and Asian (A4) populations, indicative of viral sexual transmission from Neanderthals to modern non-African humans through multiple interbreeding events in the past 80 thousand years. Remarkably, the human leukocyte antigen B*07:02 and C*07:02 alleles associated with increased risk in cervix cancer represent introgressed regions from Neanderthals in present-day Eurasians. The archaic hominin-host-switch model was also supported by other HPV variants. Niche adaptation and virus-host codivergence appear to influence the pathogenesis of papillomaviruses.
Causal attribution of human papillomavirus genotypes to invasive cervical cancer worldwide: a systematic analysis of the global literature
Understanding the proportion of invasive cervical cancer (ICC) caused by different human papillomavirus (HPV) genotypes can inform primary (ie, vaccination) and secondary (ie, screening) prevention efforts that target specific HPV genotypes. However, using the global literature to estimate population attributable fractions (AFs) requires a methodological framework to address HPV genotype-specific causality from aggregated data. We aimed to estimate the proportion of ICC caused by different HPV genotypes at the global, regional, and national level. This systematic review identified studies reporting HPV genotype-specific prevalence in ICC or people with normal cervical cytology. We searched PubMed, Embase, Scopus, and Web of Science up to Feb 29, 2024, using the search terms “cervix” and “HPV”, with no language restrictions. Odds ratios (ORs) were estimated by comparing HPV genotype-specific prevalence between HPV-positive ICC and normal cervical cytology with logistic regression models, adjusting for region, year of paper publication, and HPV primer or test. HPV genotypes with a lower bound to the 95% CI of the OR greater than 1·0 were judged as causal to ICC. Corresponding regional genotype-specific AFs were calculated as regional HPV prevalence in ICC multiplied by (1 – [1 / OR]) and were proportionally adjusted to total 100%. Global AFs were calculated from regional AFs weighted by number of regional ICC cases in 2022 (GLOBOCAN). The systematic review identified 1174 studies with 111 902 cases of HPV-positive ICC and 2 755 734 of normal cervical cytology. 17 HPV genotypes were considered causal to ICC, with ORs ranging widely from 48·3 (95% CI 45·7–50·9) for HPV16 to 1·4 (1·2–1·7) for HPV51. HPV16 had the highest global AF (61·7%), followed by HPV18 (15·3%), HPV45 (4·8%), HPV33 (3·8%), HPV58 (3·5%), HPV31 (2·8%), and HPV52 (2·8%). Remaining causal genotypes (HPV35, 59, 39, 56, 51, 68, 73, 26, 69, and 82) had a combined global AF of 5·3%. AFs for HPV16 and 18 and HPV16, 18, 31, 33, 45, 52, and 58 combined were lowest in Africa (71·9% and 92·1%, respectively) and highest in central, western, and southern Asia (83·2% and 95·9%, respectively). HPV35 had a higher AF in Africa (3·6%) than other regions (0·6–1·6%). This study provides a comprehensive global picture of HPV genotype-specific AFs in ICC, before the influence of HPV vaccination. These data can inform HPV genotype-specific vaccination and screening strategies to reduce the burden of ICC. EU Horizon 2020 Research and Innovation Programme.
Potential impact of a nine-valent vaccine in human papillomavirus related cervical disease
Background Information on human papillomavirus (HPV) type distribution is necessary to evaluate the potential impact of current and future HPV vaccines. We estimated the relative contribution (RC) to invasive cervical cancer (ICC) and precancerous cervical lesions of the nine HPV types (HPV 6/11/16/18/31/33/45/52/58) included in an HPV vaccine currently under development. Methods Estimations on ICC were based on an international study of 8,977 HPV positive cases and estimations on precancerous cervical lesions were extracted from a published meta-analysis including 115,789 HPV positive women. Globocan 2008 and 2010 World Population Prospects were used to estimate current and future projections of new ICC cases. Results RC of the 9 HPV types in ICC was 89.4%, with 18.5% of cases positive for HPV 31/33/45/52/58. Regional variations were observed. RCs varied by histology, ranging between 89.1% in squamous cell carcinomas (SCC) and 95.5% in adenocarcinomas (ADC). HPV 16/18/45 were detected in 94.2% of ADC. RC of the 9 types altogether decreased with age (trend test p < 0.0001), driven by the decrease in older ages of HPV 16/18/45. In contrast, the RC of HPV 31/33/52/58 increased with age. Due to population growth alone, projected estimates of ICC cases attributable to the 9 types are expected to rise from 493,770 new cases in 2012 to 560,887 new cases in 2025. The RCs of individual high risk HPV types varied by cytological and histological grades of HPV-positive precancerous cervical lesions, and there was an under representation of HPV 18 and 45 compared to ICC. Conclusions The addition of HPV 31/33/45/52/58 to HPV types included in current vaccines could prevent almost 90% of ICC cases worldwide. If the nine-valent vaccine achieves the same degree of efficacy than previous vaccines, world incidence rates could be substantially reduced.
Impact of Human Papillomavirus Vaccination, Rwanda and Bhutan
Rwanda and Bhutan, 2 low- and middle-income countries, implemented primarily school-based national human papillomavirus (HPV) vaccination in 2011 (Rwanda) and 2010 (Bhutan). We estimated vaccination effectiveness through urine-based HPV prevalence surveys in schools in 2013-2014 and 2017. In Rwanda, 912 participants from baseline surveys and 1,087 from repeat surveys were included, and in Bhutan, 973 participants from baseline surveys and 909 from repeat surveys were included. The overall effectiveness against vaccine-targeted HPV types (i.e., HPV-6/11/16/18) was 78% (95% CI 51%-90%) in Rwanda, and 88% (6%-99%) in Bhutan and against other α-9 types was 58% (21-78) in Rwanda and 63% (27-82) in Bhutan. No effect against other HPV types was detectable. Prevalence of vaccine-targeted HPV types decreased significantly, as well as that of other α-9 types, suggesting cross-protection. These findings provide direct evidence from low- and middle-income countries of the marked effectiveness of high-coverage school-based, national HPV vaccination programs.
Human papillomavirus, sexually transmitted infections, and antimicrobial resistance in West Africa: Estimating population burden and understanding exposures to accelerate vaccine impact and drive new interventions: The PHASE survey protocol
Human papillomavirus (HPV) infection is a primary cause of preventable deaths from cervical cancer, a condition of profound inequality with approximately 90% of deaths occurring in low- and middle-income countries, particularly in sub-Saharan Africa. In May 2018, the WHO Director-General declared a Joint Global Commitment to Cervical Cancer Elimination, highlighting the critical role of HPV vaccines in achieving this goal. However, there is a lack of systemically collected data on HPV prevalence in The Gambia, and impact data from high-income countries may not be reliably extrapolated to West African settings due to geographical variation in HPV types and distinct behavioural, biological, and sociodemographic exposures. The Gambia introduced a two-dose HPV vaccination schedule in 2019, but coverage has been very low, interrupted mainly by the COVID-19 pandemic. This presents a key opportunity to generate vital baseline data on HPV prevalence in the population before potential scale-up of vaccination efforts. The PHASE survey, a multi-stage cluster survey, aims to establish the baseline, population prevalence estimates of high-risk and low-risk, vaccine-type and non-vaccine-type HPV infection in 15- to 49-year-old females in The Gambia by measuring urinary HPV-DNA. The survey will also quantify the effects of various exposures on HPV prevalence, including sexual behaviour, the presence of other sexually-transmitted infections (STIs) - Neisseria gonorrhoea (NG), Chlamydia trachomatis (CT), Trichomonas vaginalis (TV), Mycoplasma genitalium (MG), syphilis, as well as blood borne viruses, human immunodeficiency virus (HIV), hepatitis B and hepatitis C; obstetric history, socio-demographic characteristics, and cervical cancer screening and/or treatment. Additionally, the study will provide important antimicrobial resistance (AMR) data for NG and MG in sub-Saharan Africa, a region poorly represented in global surveillance programs. This data is needed to guide regional treatment guidelines and advocate for new solutions, including gonococcal vaccines. The AMR data are expected to immediately influence recommendations regarding the appropriate choice of antibiotics for syndromic STI management in West Africa and hence to address an important driver of AMR in the sub-region. Leveraging on the Medical Research Council Unit The Gambia funded Health Demographic Surveillance system (HDSS) as its sampling frame, the survey will utilize validated diagnostic assays and culturally sensitive data collection methods, to ensure both scientific rigor and local relevance. Tools such as Audio Computer-Assisted Self-Interviewing (ACASI) technology, developed in consultation with local community advisory boards, are included to reduce social desirability bias in reporting sexual behaviour. This approach aims to maximize both the reliability and cultural appropriateness of the findings. This study directly addresses the critical need for baseline epidemiological data on HPV in a West African setting to accelerate vaccine impact and drive new interventions towards cervical cancer elimination. By understanding other factors that influence HPV (like other STIs, sexual behaviour, etc.), the study aims to ensure that, when the vaccine’s impact is measured later, changes in other confounding factors that may impact on HPV prevalence can be accounted for. The study will also establish the population prevalence of the measured STIs and their relationship to common symptoms and other adverse health outcomes related to STIs.
Global evaluation of lineage-specific human papillomavirus capsid antigenicity using antibodies elicited by natural infection
Human Papillomavirus (HPV) type variants have been classified into lineages and sublineages based upon their whole genome sequence. Here we have examined the specificity of antibodies generated following natural infection with lineage variants of oncogenic types (HPV16, 18, 31, 33, 45, 52 and 58) by testing serum samples assembled from existing archives from women residing in Africa, The Americas, Asia or Europe against representative lineage-specific pseudoviruses for each genotype. We have subjected the resulting neutralizing antibody data to antigenic clustering methods and created relational antigenic profiles for each genotype to inform the delineation of lineage-specific serotypes. For most genotypes, there was evidence of differential recognition of lineage-specific antigens and in some cases of a sufficient magnitude to suggest that some lineages should be considered antigenically distinct within their respective genotypes. These data provide compelling evidence for a degree of lineage specificity within the humoral immune response following natural infection with oncogenic HPV. Human Papillomaviruses (HPV) are classified in lineages based on their sequence. Here, the authors test neutralizing activity of sera from naturally infected women against vaccine-preventable HPV variants, delineating lineage-specific antibody responses.
Type-Specific Anal Human Papillomavirus Prevalence Among Men, According to Sexual Preference and HIV Status
A systematic literature review and meta-analysis on type-specific anal HPV prevalence identified sexual preference and HIV infection to be independent and similarly strong determinants of male anal HPV16 infection, confirming HIV-positive MSM as priorities for anal cancer prevention. Abstract Background Anal human papillomavirus (HPV) infection, most notably HPV16, the central cause of anal cancer, is increased by anal sexual intercourse and worsened by human immunodeficiency virus (HIV)-positivity. Methods A systematic review and meta-analysis of type-specific anal HPV prevalence in men, compared according to sexual preference, HIV status, and, when available, anal cytopathology. Results Seventy-nine eligible studies included: 1805 HIV-negative men who have sex with women (MSW), 924 HIV-positive MSW, 8213 HIV-negative men who have sex with men (MSM), and 12758 HIV-positive MSM. Irrespective of anal cytopathology, HPV16 prevalence was significantly higher in MSM than MSW, both among HIV-negative (14% vs 3%; prevalence ratio (PR) 4.7; 95% confidence interval [CI] 2.5–8.9) and HIV-positive men (30% vs 11%; PR = 2.8; 95% CI, 1.9–4.1). Likewise, HPV16 was significantly higher in HIV-positive than HIV-negative men, both among MSW (PR = 3.5; 95% CI, 1.6–7.7) and MSM (PR = 2.1; 95% CI, 1.8–2.5). Anal HPV16 prevalence was similar between HIV-positive MSW and HIV-negative MSM. For MSM, anal HPV16 prevalence was significantly higher from studies with anal cytopathology, suggesting population sampling effects. Conclusion Sexual preference and HIV infection are independent strong determinants of male anal HPV16 infection, confirming HIV-positive MSM as priorities for anal cancer prevention.
Genome-wide association meta-analysis identifies pleiotropic risk loci for aerodigestive squamous cell cancers
Squamous cell carcinomas (SqCC) of the aerodigestive tract have similar etiological risk factors. Although genetic risk variants for individual cancers have been identified, an agnostic, genome-wide search for shared genetic susceptibility has not been performed. To identify novel and pleotropic SqCC risk variants, we performed a meta-analysis of GWAS data on lung SqCC (LuSqCC), oro/pharyngeal SqCC (OSqCC), laryngeal SqCC (LaSqCC) and esophageal SqCC (ESqCC) cancers, totaling 13,887 cases and 61,961 controls of European ancestry. We identified one novel genome-wide significant ( P meta <5x10 -8 ) aerodigestive SqCC susceptibility loci in the 2q33.1 region (rs56321285, TMEM273 ). Additionally, three previously unknown loci reached suggestive significance ( P meta <5x10 -7 ): 1q32.1 (rs12133735, near MDM4 ), 5q31.2 (rs13181561, TMEM173 ) and 19p13.11 (rs61494113, ABHD8) . Multiple previously identified loci for aerodigestive SqCC also showed evidence of pleiotropy in at least another SqCC site, these include: 4q23 ( ADH1B ), 6p21.33 ( STK19 ), 6p21.32 ( HLA-DQB1 ), 9p21.33 ( CDKN2B-AS1 ) and 13q13.1( BRCA2 ). Gene-based association and gene set enrichment identified a set of 48 SqCC-related genes rel to DNA damage and epigenetic regulation pathways. Our study highlights the importance of cross-cancer analyses to identify pleiotropic risk loci of histology-related cancers arising at distinct anatomical sites.