A high and increasing HPV prevalence in tonsillar cancers in Eastern Denmark, 2000–2010: The largest registry‐based study to date

The aim was to explore whether the incidence of tonsillar squamous cell carcinomas (TSCCs) increased in Eastern Denmark, 2000–2010, and whether human papillomavirus (HPV) could explain the increase, and to assess the association of HPV prevalence with gender, age, and origin (i.e., the certainty of tonsillar tumor origin). We applied HPV DNA PCR and p16 immunohistochemistry to all TSCCs registered in the Danish Head and Neck Cancer Group (DAHANCA) and in the Danish Pathology Data Bank (n = 632). Pathologists reviewed and subdivided the tumors into two groups: specified and nonspecified TSCCs. Approximately 10% of HPV‐positive tumors was genotyped by amplicon next‐generation sequencing. The overall crude incidence of TSCCs increased significantly (2.7% per year) and was explained by an increasing incidence of HPV‐positive TSCCs (4.9% per year). The overall HPV prevalence was 58%, with HPV16 being the predominant HPV type. In multivariate analysis, the HPV prevalence was associated with age (<55 vs. >60 years) (OR, 1.72; 95% CI 1.13–2.63) and origin (nonspecified vs. specified TSCCs) (OR, 0.15; 95% CI 0.11–0.22). The association of HPV prevalence with origin increased over time in specified TSCCs (OR per year, 1.10; 95% CI 1.01–1.19), whereas no change over time was observed among nonspecified TSCCs (OR per year, 0.99; 95% CI 0.90–1.08). In conclusion, the observed increase in the number of HPV‐positive TSCCs can explain the increasing number of TSCCs in Eastern Denmark, 2000–2010. HPV prevalence was associated with younger age (<55 years) and a high certainty of tonsillar tumor origin.     

Heritable variation in telomere length predicts mortality in Soay sheep

Telomere length (TL) is considered an important biomarker of whole-organism health and aging. Across humans and other vertebrates, short telomeres are associated with increased subsequent mortality risk, but the processes responsible for this correlation remain uncertain. A key unanswered question is whether TL–mortality associations arise due to positive effects of genes or early-life environment on both an individual’s average lifetime TL and their longevity, or due to more immediate effects of environmental stressors on within-individual TL loss and increased mortality risk. Addressing this question requires longitudinal TL and life history data across the entire lifetimes of many individuals, which are difficult to obtain for long-lived species like humans. Using longitudinal data and samples collected over nearly two decades, as part of a long-term study of wild Soay sheep, we dissected an observed positive association between TL and subsequent survival using multivariate quantitative genetic models. We found no evidence that telomere attrition was associated with increased mortality risk, suggesting that TL is not an important marker of biological aging or exposure to environmental stress in our study system. Instead, we find that among-individual differences in average TL are associated with increased lifespan. Our analyses suggest that this correlation between an individual’s average TL and lifespan has a genetic basis. This demonstrates that TL has the potential to evolve under natural conditions, and suggests an important role of genetics underlying the widespread observation that short telomeres predict mortality.

Telomeres are repetitive sequences of noncoding DNA found at the terminal ends of linear chromosomes, and they play an important role in maintaining DNA stability and integrity (1–3). Telomeres shorten during cell replication and in response to oxidative stress (4, 5), and cellular senescence and apoptosis is triggered once telomeres reach a critically short threshold (2). The important role of telomeres in cellular senescence has led to telomere shortening being considered as one of nine “hallmarks of aging,” and average telomere length (TL) as an important biomarker of whole-organism health and biological aging (6). In humans, relatively short leukocyte telomeres have been linked to a range of age-related diseases such as diabetes, cancer, and cardiovascular disease (7–9) and increased subsequent mortality risk (10–12). A recent metaanalysis suggests this pattern may generalize beyond humans: Across studies from 20 nonmodel vertebrate species (predominantly birds), there was an overall positive association between TL and subsequent survival (13). Although evidence for a causal role for telomeres in whole-organism aging and longevity remains weak (14), these findings highlight the potential significance of TL as a biomarker of human and animal health (15, 16) and for our understanding of life history evolution (17, 18).Studies in humans and other vertebrates have found evidence for consistent differences in TL among individuals over multiple measurements (19, 20). Such repeatable among-individual differences in any trait may result from the trait being under genetic influence, from long-term effects of the early-life environment, and/or environmental conditions that persist across the lifetime. There is good evidence that variation in average TL in blood cells has a genetic basis in humans and other vertebrates, although estimates of the heritability (the proportion of variation attributed to additive genetic effects) of TL are variable (21, 22). Recent studies of wild vertebrates have also revealed considerable variation in adult TL among birth cohorts, suggesting persistent impacts of early-life environment (23, 24). At the same time, there is growing evidence that TL is highly dynamic across an individual’s lifetime, and metaanalyses of human and nonhuman animal studies show that experience of diverse forms of environmental stress are predictive of shorter TL (25–27). Indeed, some studies using longitudinal TL data have found that telomere shortening over successive measurements rather than TL per se is predictive of mortality (28–30). Thus, the emerging picture from studies in humans and other vertebrates is that shorter TL generally predicts increased risk of subsequent mortality, and that variation in TL is under the influence of both genetics and environmental stressors.The observation that shorter TL measurements predict increased mortality risk could be underpinned by two nonmutually exclusive processes operating across the lifetimes of individuals. Firstly, individuals may differ in their average TL across life, and individuals with shorter TL may be shorter lived. This pattern is referred to as the “selective disappearance” of individuals with shorter telomeres, and it implies that TL reflects constitutive differences among individuals (for example, due to genetics or differences in early-life environment) which shape their longevity (31, 32). Secondly, individuals may differ in their pattern of TL change over time, and individuals showing the greatest telomere loss across successive measurements are more likely to die subsequently. This pattern is consistent with the idea that within-individual telomere dynamics reflect recent and cumulative experiences of environmental stress and physiological deterioration that also predict mortality. Neither pattern necessarily implies a causal role for telomeres in driving the mortality risk of an organism, because associations between TL and survival could result from both traits being correlated with underlying, unmeasured variables which causally impact survival (14, 18). Nevertheless, unraveling the contribution of genetics, early-life environment, and more immediate telomere shortening to the observed association between TL and survival is essential for our understanding of TL as a biomarker of health and aging (19).To our knowledge, no study to date has assessed the relative importance of the different processes underlying the relationship between TL and mortality risk across the entire lifespan. To do so demands repeated measurements from across life to characterize among- and within-individual variation in TL, a population pedigree or genomic information to separate genetic and environmental sources of variation, and detailed information on individual health and fitness outcomes over the lifetime. Here, we use a multivariate mixed-effects modeling approach to analyze extensive, longitudinal data from a long-term study of wild Soay sheep living on St Kilda, Scotland, to distinguish between possible models of why shorter TL predicts increased mortality risk. We find that the observed positive association between TL and mortality in this system is underpinned by selective disappearance of individuals with shorter average TL. Importantly, our results suggest this is largely driven by genetically based differences in both TL and longevity.     

Host Cell Entry and Neutralization Sensitivity of SARS-CoV-2 Lineages B.1.620 and R.1

The spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) facilitates viral entry into host cells and is the key target for neutralizing antibodies. The SARS-CoV-2 lineage B.1.620 carries fifteen mutations in the S protein and is spread in Africa, the US and Europe, while lineage R.1 harbors four mutations in S and infections were observed in several countries, particularly Japan and the US. However, the impact of the mutations in B.1.620 and R.1 S proteins on antibody-mediated neutralization and host cell entry are largely unknown. Here, we report that these mutations are compatible with robust ACE2 binding and entry into cell lines, and they markedly reduce neutralization by vaccine-induced antibodies. Our results reveal evasion of neutralizing antibodies by B.1.620 and R.1, which might have contributed to the spread of these lineages.     

Zur Analyse der hydrophilen Kolloide in den Kolonien von Paratyphus B

Ohne ZusammenfassungMit 1 Textabbildung.     

Die Staphylokokkenesterase und ihre Beziehung zum Hämolysin

Ohne Zusammenfassung