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Root-associated fungi could play a role in determining both the positive relationship between plant diversity and productivity in experimental grasslands, and its strengthening over time. This hypothesis assumes that specialized pathogenic and mutualistic fungal communities gradually assemble over time, enhancing plant growth more in species-rich than in species-poor plots. To test this hypothesis, we used high-throughput amplicon sequencing to characterize root-associated fungal communities in experimental grasslands of 1 and 15 years of age with varying levels of plant species richness. Specifically, we tested whether the relationship between fungal communities and plant richness and productivity becomes stronger with the age of the experimental plots. Our results showed that fungal diversity increased with plant diversity, but this relationship weakened rather than strengthened over the two time points. Contrastingly, fungal community composition showed increasing associations with plant diversity over time, suggesting a gradual build-up of specific fungal assemblages. Analyses of different fungal guilds showed that these changes were particularly marked in pathogenic fungi, whose shifts in relative abundance are consistent with the pathogen dilution hypothesis in diverse plant communities. Our results suggest that root-associated fungal pathogens play more specific roles in determining the diversity-productivity relationship than other root-associated plant symbionts.
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Micobioma , Micobioma/genética , Raíces de Plantas/microbiología , Hongos/genética , Plantas , Simbiosis/genética , Microbiología del SueloRESUMEN
Per- and polyfluoroalkyl substances (PFAS) are environmentally persistent organic pollutants detectable in the serum of most U.S. adults. Some studies of highly-exposed individuals have suggested an association between PFAS and prostate cancer, but evidence from population-based studies is limited. We investigated the association between pre-diagnostic serum PFAS concentrations and aggressive prostate cancer risk in a large prospective study. We measured pre-diagnostic serum concentrations of eight PFAS, including perfluorooctanoate (PFOA), for 750 aggressive prostate cancer cases and 750 individually matched controls within the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. We assessed the reproducibility of PFAS concentrations in serial samples collected up to six years apart among 60 controls using intraclass correlation coefficients (ICCs). Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association with prostate cancer, adjusting for other PFAS and potential confounders. Concentrations of most PFAS were consistent (ICC>0.7) across the serial samples over time. We observed an inverse association between PFOA and aggressive prostate cancer (ORcontinuous = 0.79, 95% CI = 0.63, 0.99), but the association was limited to cases diagnosed ≤3 years after blood collection and became statistically non-significant for cases diagnosed with later follow-up (>3 years, ORcontinuous = 0.90, 95% CI = 0.79, 1.03). Other PFAS were not associated with aggressive prostate cancer risk. Although we cannot rule out an increased risk at higher levels, our findings from a population with PFAS serum concentrations comparable to the general population do not support an association with increased risk of aggressive prostate cancer.
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Ácidos Alcanesulfónicos , Contaminantes Ambientales , Fluorocarburos , Neoplasias de la Próstata , Adulto , Masculino , Humanos , Estudios Prospectivos , Estudios de Casos y Controles , Reproducibilidad de los Resultados , Neoplasias de la Próstata/inducido químicamente , Neoplasias de la Próstata/epidemiologíaRESUMEN
Feedback between plants and soil microbial communities can be a powerful driver of vegetation dynamics. Plants elicit changes in the soil microbiome that either promote or suppress conspecifics at the same location, thereby regulating population density-dependence and species co-existence. Such effects are often attributed to the accumulation of host-specific antagonistic or beneficial microbiota in the rhizosphere. However, the identity and host-specificity of the microbial taxa involved are rarely empirically assessed. Here we review the evidence for host-specificity in plant-associated microbes and propose that specific plant-soil feedbacks can also be driven by generalists. We outline the potential mechanisms by which generalist microbial pathogens, mutualists and decomposers can generate differential effects on plant hosts and synthesize existing evidence to predict these effects as a function of plant investments into defence, microbial mutualists and dispersal. Importantly, the capacity of generalist microbiota to drive plant-soil feedbacks depends not only on the traits of individual plants but also on the phylogenetic and functional diversity of plant communities. Identifying factors that promote specialization or generalism in plant-microbial interactions and thereby modulate the impact of microbiota on plant performance will advance our understanding of the mechanisms underlying plant-soil feedback and the ways it contributes to plant co-existence.
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Microbiología del Suelo , Suelo , Retroalimentación , Filogenia , Raíces de Plantas/fisiología , Plantas , Rizosfera , SimbiosisRESUMEN
Grazing and global change (e.g., warming, nitrogen deposition, and altered precipitation) both contribute to biodiversity loss and alter ecosystem structure and functioning. However, how grazing and global change interactively influence plant diversity and ecosystem productivity, and their relationship remains unclear at the global scale. Here, we synthesized 73 field studies to quantify the individual and/or interactive effects of grazing and global change factors on biodiversity-productivity relationship in grasslands. Our results showed that grazing significantly reduced plant richness by 3.7% and aboveground net primary productivity (ANPP) by 29.1%, but increased belowground net primary productivity (BNPP) by 9.3%. Global change factors, however, decreased richness by 8.0% but increased ANPP and BNPP by 13.4% and 14.9%, respectively. Interestingly, the strength of the change in biodiversity in response to grazing was positively correlated with the strength of the change in BNPP. Yet, global change flipped these relationships from positive to negative even when combined with grazing. These results indicate that the impacts of global change factors are more dominant than grazing on the belowground biodiversity-productivity relationship, which is contrary to the pattern of aboveground one. Therefore, incorporating global change factors with herbivore grazing into Earth system models is necessary to accurately predict climate-grassland carbon cycle feedbacks in the Anthropocene.
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Ecosistema , Pradera , Biodiversidad , Ciclo del Carbono , Cambio Climático , PlantasRESUMEN
Community composition is a primary determinant of how biodiversity change influences ecosystem functioning and, therefore, the relationship between biodiversity and ecosystem functioning (BEF). We examine the consequences of community composition across six structurally realistic plant community models. We find that a positive correlation between species' functioning in monoculture versus their dominance in mixture with regard to a specific function (the "function-dominance correlation") generates a positive relationship between realised diversity and ecosystem functioning across species richness treatments. However, because realised diversity declines when few species dominate, a positive function-dominance correlation generates a negative relationship between realised diversity and ecosystem functioning within species richness treatments. Removing seed inflow strengthens the link between the function-dominance correlation and BEF relationships across species richness treatments but weakens it within them. These results suggest that changes in species' identities in a local species pool may more strongly affect ecosystem functioning than changes in species richness.
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Biodiversidad , EcosistemaRESUMEN
BACKGROUND: Studying the differential impact of aspirin and other nonsteroidal anti-inflammatory drugs across the stages of colorectal neoplasia from early adenoma to cancer is critical for understanding the benefits of these widely used drugs. METHODS: With 13 years of follow-up, the authors prospectively evaluated the association between aspirin and ibuprofen use and incident distal adenoma (1221 cases), recurrent adenoma (862 cases), and incident colorectal cancer (CRC; 2826 cases) among men and women in the population-based Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. With multivariable-adjusted models, odds ratio (ORs) and 95% confidence intervals (CIs) for adenoma incidence and recurrence and hazard ratios (HRs) and 95% CIs for incident CRC were determined. RESULTS: The authors observed a significantly reduced risk of incident adenoma with ibuprofen use (≥30 vs <4 pills per month: OR, 0.76 [95% CI, 0.60-0.95]; Ptrend = .04), particularly advanced adenoma (OR, 0.48 [95% CI, 0.28-0.83]; Ptrend = .005). Among those with a previous adenoma detected through screening, aspirin use was associated with a decreased risk of advanced recurrent adenoma (≥30 vs <4 pills per month: OR, 0.56 [95% CI, 0.36-0.87]; Ptrend = 0.006). Both aspirin (HR, 0.88 [95% CI, 0.81-0.96]; Ptrend <.0001) and ibuprofen use (HR, 0.81 [95% CI, 0.70-0.93); Ptrend = 0.003) ≥30 versus <4 pills per month were significantly associated with reduced CRC risk. CONCLUSIONS: In this large prospective study with long-term follow-up, a beneficial role for not only aspirin, but also ibuprofen, in preventing advanced adenoma and curbing progression to recurrence and cancer among older adults was observed.
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Adenoma , Neoplasias Colorrectales , Adenoma/diagnóstico , Adenoma/epidemiología , Adenoma/prevención & control , Anciano , Aspirina/uso terapéutico , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/prevención & control , Detección Precoz del Cáncer , Femenino , Humanos , Ibuprofeno/uso terapéutico , Incidencia , Masculino , Estudios ProspectivosRESUMEN
BACKGROUND: N-nitroso compounds are hypothesized human bladder carcinogens. We investigated ingestion of N-nitroso compound precursors nitrate and nitrite from drinking water and diet and bladder cancer in the New England Bladder Cancer Study. METHODS: Using historical nitrate measurements for public water supplies and measured and modeled values for private wells, as well as self-reported water intake, we estimated average nitrate concentrations (mg/L NO3-N) and average daily nitrate intake (mg/d) from 1970 to diagnosis/reference date (987 cases and 1,180 controls). We estimated overall and source-specific dietary nitrate and nitrite intakes using a food frequency questionnaire (1,037 cases and 1,225 controls). We used unconditional logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI). We evaluated interactions with factors that may affect N-nitroso compound formation (i.e., red meat, vitamin C, smoking), and with water intake. RESULTS: Average drinking water nitrate concentration above the 95th percentile (>2.07 mg/L) compared with the lowest quartile (≤0.21 mg/L) was associated with bladder cancer (OR = 1.5, 95% CI = 0.97, 2.3; P trend = 0.01); the association was similar for average daily drinking water nitrate intake. We observed positive associations for dietary nitrate and nitrite intakes from processed meat (highest versus lowest quintile OR for nitrate = 1.4, 95% CI = 1.0, 2.0; P trend = 0.04; OR for nitrite = 1.5, 95% CI = 1.0, 2.1; P trend = 0.04, respectively), but not other dietary sources. We observed positive interactions between drinking water nitrate and red meat (P-interaction 0.05) and processed red meat (0.07). CONCLUSIONS: Our results suggest the importance of both drinking water and dietary nitrate sources as risk factors for bladder cancer.
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Dieta , Agua Potable , Nitratos , Nitritos , Neoplasias de la Vejiga Urinaria , Adulto , Anciano , Dieta/efectos adversos , Encuestas sobre Dietas , Agua Potable/efectos adversos , Agua Potable/química , Femenino , Humanos , Masculino , Persona de Mediana Edad , New England/epidemiología , Nitratos/efectos adversos , Nitratos/análisis , Nitritos/efectos adversos , Nitritos/análisis , Carne Roja/efectos adversos , Factores de Riesgo , Neoplasias de la Vejiga Urinaria/inducido químicamente , Neoplasias de la Vejiga Urinaria/epidemiologíaRESUMEN
BACKGROUND: Chromosome 8q24 has emerged as an important genetic susceptibility region for several cancers, including prostate cancer; however, little is known about the contribution of DNA methylation in this region to risk. METHODS: We prospectively evaluated DNA methylation at 8q24 in relation to prostate cancer using pre-diagnostic blood samples from 694 prostate cancer cases (including 172 aggressive cases) and 703 controls in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. We used logistic regression to estimate odds ratios and 95% confidence intervals. RESULTS: Although none remained significant after adjustment for multiple testing (q>0.05), of the 50 CpG sites meeting quality control, we identified 8 sites that were nominally associated with prostate cancer (Ptrend<0.05), including 6 correlated (Spearman ρ: 0.20-0.52) sites in POU5F1B and 2 intergenic sites (most significant site: Chr8:128428897 in POU5F1B, Ptrend=0.01). We also identified two correlated (ρ=0.39) sites in MYC (Chr8:128753187 and Chr8:128753154) that were associated with aggressive (Ptrend=0.02 and 0.03), but not non-aggressive disease (Ptrend=0.70 and 0.20; Pheterogeneity=0.01 and 4.6 × 10-3). These findings persisted after adjustment for the top 8q24 prostate cancer variants in our study. CONCLUSIONS: Although requiring replication, our findings provide some evidence that 8q24 DNA methylation levels may be associated with prostate cancer risk.
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Cromosomas Humanos Par 8 , Metilación de ADN , ADN/sangre , Genes myc , Proteínas de Homeodominio/genética , Neoplasias de la Próstata/genética , Anciano , Estudios de Casos y Controles , Islas de CpG , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Estudios Prospectivos , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/diagnóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Factores de RiesgoRESUMEN
Plant diversity influences many ecosystem functions including root decomposition. However, due to the presence of multiple pathways via which plant diversity may affect root decomposition, our mechanistic understanding of their relationships is limited. In a grassland biodiversity experiment, we simultaneously assessed the effects of three pathways-root litter quality, soil biota, and soil abiotic conditions-on the relationships between plant diversity (in terms of species richness and the presence/absence of grasses and legumes) and root decomposition using structural equation modeling. Our final structural equation model explained 70% of the variation in root mass loss. However, different measures of plant diversity included in our model operated via different pathways to alter root mass loss. Plant species richness had a negative effect on root mass loss. This was partially due to increased Oribatida abundance, but was weakened by enhanced root potassium (K) concentration in more diverse mixtures. Equally, grass presence negatively affected root mass loss. This effect of grasses was mostly mediated via increased root lignin concentration and supported via increased Oribatida abundance and decreased root K concentration. In contrast, legume presence showed a net positive effect on root mass loss via decreased root lignin concentration and increased root magnesium concentration, both of which led to enhanced root mass loss. Overall, the different measures of plant diversity had contrasting effects on root decomposition. Furthermore, we found that root chemistry and soil biota but not root morphology or soil abiotic conditions mediated these effects of plant diversity on root decomposition.
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Biodiversidad , Fabaceae/fisiología , Raíces de Plantas/química , Poaceae/fisiología , Suelo/química , Ecosistema , Microbiología del SueloRESUMEN
BACKGROUND: Evidence suggests that global blood DNA methylation levels may be associated with the risk of various cancers, but no studies have evaluated this relationship for prostate cancer. METHODS: We used pyrosequencing to quantify DNA methylation levels at the long interspersed nuclear element 1 (LINE-1) and Alu repetitive elements in pre-diagnostic blood samples from 694 prostate cancer cases and 703 controls from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. We evaluated prostate cancer risk associated with the mean methylation level for each element using logistic regression, adjusting for potential confounders. RESULTS: We did not observe a significant association with prostate cancer for LINE-1 [odds ratio (OR) for the highest compared to the lowest quartile = 1.01, 95% confidence interval (CI): 0.73-1.39, Ptrend = 0.99] or Alu (OR = 0.94, 95% CI: 0.68-1.29, Ptrend = 0.69) methylation levels overall. However, for Alu, we observed that higher DNA methylation levels were associated with a significant increased risk for those diagnosed 4 or more years after blood draw (OR = 2.26, 95% CI: 1.27-4.00, Ptrend = 4.4 × 10(-3) ). In contrast, there was no association for those diagnosed 2 (OR = 1.13, 95% CI: 0.67-1.90, Ptrend = 0.64) or 3 years after draw (OR = 1.22, 95% CI: 0.71-2.07, Ptrend = 0.32), and a decreased risk for those diagnosed less than 2 years after draw (OR = 0.40, 95% CI: 0.25-0.65, Ptrend = 3.8 × 10(-5) ; Pheterogeneity = 5.3 × 10(-6) ). CONCLUSIONS: Although LINE-1 DNA methylation levels were not associated with prostate cancer, we observed an association for Alu that varied by time from blood draw to diagnosis. Our study suggests that elevated Alu blood DNA methylation levels several years before diagnosis may be associated with an increased prostate cancer risk.
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Elementos Alu/genética , Metilación de ADN , Elementos de Nucleótido Esparcido Largo/genética , Neoplasias de la Próstata/genética , Anciano , Estudios de Casos y Controles , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/patología , RiesgoRESUMEN
Plant species leave a chemical signature in the soils below them, generating fine-scale spatial variation that drives ecological processes. Since the publication of a seminal paper on plant-mediated soil heterogeneity by Paul Zinke in 1962, a robust literature has developed examining effects of individual plants on their local environments (individual plant effects). Here, we synthesize this work using meta-analysis to show that plant effects are strong and pervasive across ecosystems on six continents. Overall, soil properties beneath individual plants differ from those of neighbours by an average of 41%. Although the magnitudes of individual plant effects exhibit weak relationships with climate and latitude, they are significantly stronger in deserts and tundra than forests, and weaker in intensively managed ecosystems. The ubiquitous effects of plant individuals and species on local soil properties imply that individual plant effects have a role in plant-soil feedbacks, linking individual plants with biogeochemical processes at the ecosystem scale.
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Ecosistema , Fenómenos Fisiológicos de las Plantas , Suelo/químicaRESUMEN
Many pharmaceuticals and personal care products (PPCPs) have been shown to be biotransformed in water treatment systems. However, little research exists on the effect of initial PPCP concentration on PPCP biotransformation or on the microbial communities treating impacted water. In this study, biological PPCP removal at various concentrations was assessed using laboratory columns inoculated with wastewater treatment plant effluent. Pyrosequencing was used to examine microbial communities in the columns and in soil from a soil aquifer treatment (SAT; a method of water treatment prior to reuse) site. Laboratory columns were supplied with different concentrations (0.25, 10, 100, or 1,000 µg liter(-1)) of each of 15 PPCPs. Five PPCPs (4-isopropyl-3-methylphenol [biosol], p-chloro-m-xylenol, gemfibrozil, ketoprofen, and phenytoin) were not removed at any tested concentrations. Two PPCPs (naproxen and triclosan) exhibited removals independent of PPCP concentration. PPCP removal efficiencies were dependent on initial concentrations for biphenylol, p-chloro-m-cresol, chlorophene, diclofenac, 5-fluorouracil, ibuprofen, and valproic acid, showing that PPCP concentration can affect biotransformation. Biofilms from sand samples collected from the 0.25- and 10-µg liter(-1) PPCP columns were pyrosequenced along with SAT soil samples collected on three consecutive days of a wetting and drying cycle to enable comparison of these two communities exposed to PPCPs. SAT communities were similar to column communities in taxonomy and phylotype composition, and both were found to contain close relatives of known PPCP degraders. The efficiency of biological removal of PPCPs was found to be dependent on the concentration at which the contamination occurs for some, but not all, PPCPs.
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Biota , Cosméticos/metabolismo , Preparaciones Farmacéuticas/metabolismo , Reciclaje , Microbiología del Suelo , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua , BiotransformaciónRESUMEN
CONTEXT: There has been a dramatic increase in the use of prostate magnetic resonance imaging (MRI) in the diagnostic workup. With prostate volume calculated from MRI, prostate-specific antigen density (PSAD) now is a ready-to-use parameter for prostate cancer (PCa) risk stratification before prostate biopsy, especially among patients with negative MRI or equivocal lesions. OBJECTIVE: In this review, we aimed to evaluate the diagnostic performance of PSAD for clinically significant prostate cancer (CSPCa) among patients who received MRI before prostate biopsy. EVIDENCE ACQUISITION: Two investigators performed a systematic review according of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) criteria. Studies (published between January 1, 2012, and December 31, 2021) reporting the diagnostic performance (outcomes) of PSAD (intervention) for CSPCa among men who received prebiopsy prostate MRI and subsequent prostate biopsy (patients), using biopsy pathology as the gold standard (comparison), were eligible for inclusion. EVIDENCE SYNTHESIS: A total of 1536 papers were identified in PubMed, Scopus, and Embase. Of these, 248 studies were reviewed in detail and 39 were qualified. The pooled sensitivity (SENS) and specificity (SPEC) for diagnosing CSPCa among patients with positive MRI were, respectively, 0.87 and 0.35 for PSAD of 0.1 ng/ml/ml, 0.74 and 0.61 for PSAD of 0.15 ng/ml/ml, and 0.51 and 0.81 for PSAD of 0.2 ng/ml/ml. The pooled SENS and SPEC for diagnosing CSPCa among patients with negative MRI were, respectively, 0.85 and 0.36 for PSAD of 0.1 ng/ml/ml, 0.60 and 0.66 for PSAD of 0.15 ng/ml/ml, and 0.33 and 0.84 for PSAD of 0.2 ng/ml/ml. The pooled SENS and SPEC among patients with Prostate Imaging Reporting and Data System (PI-RADS) 3 or Likert 3 lesions were, respectively, 0.87 and 0.39 for PSAD of 0.1 ng/ml/ml, 0.61 and 0.69 for PSAD of 0.15 ng/ml/ml, and 0.42 and 0.82 for PSAD of 0.2 ng/ml/ml. The post-test probability for CSPCa among patients with negative MRI was 6% if PSAD was <0.15 ng/ml/ml and dropped to 4% if PSAD was <0.10 ng/ml/ml. CONCLUSIONS: In this systematic review, we quantitatively evaluated the diagnosis performance of PSAD for CSPCa in combination with prostate MRI. It demonstrated a complementary performance and predictive value, especially among patients with negative MRI and PI-RADS 3 or Likert 3 lesions. Integration of PSAD into decision-making for prostate biopsy may facilitate improved risk-adjusted care. PATIENT SUMMARY: Prostate-specific antigen density is a ready-to-use parameter in the era of increased magnetic resonance imaging (MRI) use in clinically significant prostate cancer (CSPCa) diagnosis. Findings suggest that the chance of having CSPCa was very low (4% or 6% for those with negative prebiopsy MRI or Prostate Imaging Reporting and Data System (Likert) score 3 lesion, respectively, if the PSAD was <0.10 ng/ml/ml), which may lower the need for biopsy in these patients.
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Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Imagen por Resonancia Magnética/métodos , Antígeno Prostático Específico , Estudios Retrospectivos , Espectroscopía de Resonancia MagnéticaRESUMEN
With advances in the early detection and treatment of cancer, the incidence of multiple primary cancers (MPC) or second primary cancers has increased over time. Characterization of etiologic risk factors, including family history of cancer, within the general population is critical for assessing MPC risk in patients. We examined the association between family history of cancer among first-degree relatives and MPC risk in a prospective study of 139,958 participants from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Cox proportional hazard models were used to calculate HRs and 95% confidence intervals (95% CI), adjusting for potential confounders. Over a median follow-up of 16 years (IQR: 11-19 years), 6,170 participants were diagnosed with MPC. Having a family history of cancer increased the risk of MPC by 18% (HR, 1.18; 95% CI, 1.12-1.24). A positive linear trend was observed between the reported number of cancers in the family history and MPC risk with HRs (95% CI) of 1.13 (1.07-1.20), 1.23 (1.14-1.33), 1.29 (1.15-1.45), and 1.42 (1.20-1.70) for one, two, three, and four or more cancers among first-degree relatives, respectively (Ptrend = 2.36 × 10-13). No significant differences were observed by cancer histology or specific cancer types reported in the family history. Our study demonstrates that the family history of cancer is an important risk factor for the development of MPCs and that a comprehensive assessment of the number of cancers reported among first-degree relatives may identify those at higher risk who may benefit from targeted cancer prevention and screening strategies. Prevention Relevance: Our study makes a substantial contribution to the understanding of risk factors for MPCs in the general population. It demonstrates that individuals with a strong family history of cancer are at higher risk for MPCs and may benefit from more targeted cancer prevention and screening interventions.
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With advances in the early detection and treatment of cancer, the incidence of multiple primary cancers (MPC), or second primary cancers, has risen over time. Characterization of etiologic risk factors, including family history of cancer, within the general population is critical for assessing MPC risk in patients. We examined the association between family history of cancer among first-degree relatives and MPC risk in a prospective study of 139,958 participants from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Cox proportional hazard models were used to calculate hazard ratios (HR) and 95% confidence intervals (95%CI), adjusting for potential confounders. Over a median follow-up of 16 years (interquartile range: 11-19 years), 6,170 participants were diagnosed with MPC. Having a family history of cancer increased the risk of MPC by 18% (HR=1.18, 95%CI: 1.12-1.24). A positive linear trend was observed between the reported number of cancers in the family history and MPC risk with HRs (95%CI) of 1.13 (1.07-1.20), 1.23 (1.14-1.33), 1.29 (1.15-1.45), and 1.42 (1.20-1.70) for 1, 2, 3, and 4+ cancers among first-degree relatives, respectively (Ptrend=2.36x10-13). No significant differences were observed by cancer histology or specific types of cancer reported in the family history. Our study demonstrates that family history of cancer is an important risk factor for the development of multiple primary cancers and that a comprehensive of assessment of the number of cancers reported among first-degree relatives may identify those at higher risk who may benefit from targeted cancer prevention and screening strategies.
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Effects of plant diversity on grassland productivity, or overyielding, are found to be robust to nutrient enrichment. However, the impact of cumulative nitrogen (N) addition (total N added over time) on overyielding and its drivers are underexplored. Synthesizing data from 15 multi-year grassland biodiversity experiments with N addition, we found that N addition decreases complementarity effects and increases selection effects proportionately, resulting in no overall change in overyielding regardless of N addition rate. However, we observed a convex relationship between overyielding and cumulative N addition, driven by a shift from complementarity to selection effects. This shift suggests diminishing positive interactions and an increasing contribution of a few dominant species with increasing N accumulation. Recognizing the importance of cumulative N addition is vital for understanding its impacts on grassland overyielding, contributing essential insights for biodiversity conservation and ecosystem resilience in the face of increasing N deposition.
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Ecosistema , Pradera , Nitrógeno , Biodiversidad , PlantasRESUMEN
Importance: African American men experience greater prostate cancer incidence and mortality than White men. Growing literature supports associations of neighborhood disadvantage, which disproportionately affects African American men, with aggressive prostate cancer; chronic stress and downstream biological impacts (eg, increased inflammation) may contribute to these associations. Objective: To examine whether several neighborhood disadvantage metrics are associated with prostate tumor RNA expression of stress-related genes. Design, Setting, and Participants: This cross-sectional study leveraged prostate tumor transcriptomic data for African American and White men with prostate cancer who received radical prostatectomy at the University of Maryland Medical Center between August 1992 and January 2021. Data were analyzed from May 2023 to April 2024. Exposures: Using addresses at diagnosis, 2 neighborhood deprivation metrics (Area Deprivation Index [ADI] and validated bayesian Neighborhood Deprivation Index) as well as the Racial Isolation Index (RI) and historical redlining were applied to participants' addresses. Self-reported race was determined using electronic medical records. Main Outcomes and Measures: A total of 105 stress-related genes were evaluated with each neighborhood metric using linear regression, adjusting for race, age, and year of surgery. Genes in the Conserved Transcriptional Response to Adversity (CTRA) and stress-related signaling genes were included. Results: A total of 218 men (168 [77%] African American, 50 [23%] White) with a median (IQR) age of 58 (53-63) years were included. African American participants experienced greater neighborhood disadvantage than White participants (median [IQR] ADI, 115 [100-130] vs 92 [83-104]; median [IQR] RI, 0.68 [0.34-0.87] vs 0.11 [0.06-0.14]). ADI was positively associated with expression for 11 genes; HTR6 (serotonin pathway) remained significant after multiple-comparison adjustment (ß = 0.003; SE, 0.001; P < .001; Benjamini-Hochberg q value = .01). Several genes, including HTR6, were associated with multiple metrics. We observed higher expression of 5 proinflammatory genes in the CTRA with greater neighborhood disadvantage (eg, CXCL8 and ADI, ß = 0.008; SE, 0.003; P = .01; q value = .21). Conclusions and Relevance: In this cross-sectional study, the expression of several stress-related genes in prostate tumors was higher among men residing in disadvantaged neighborhoods. This study is one of the first to suggest associations of neighborhood disadvantage with prostate tumor RNA expression. Additional research is needed in larger studies to replicate findings and further investigate interrelationships of neighborhood factors, tumor biology, and aggressive prostate cancer to inform interventions to reduce disparities.
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Negro o Afroamericano , Neoplasias de la Próstata , Blanco , Anciano , Humanos , Masculino , Persona de Mediana Edad , Negro o Afroamericano/estadística & datos numéricos , Negro o Afroamericano/genética , Estudios Transversales , Maryland/epidemiología , Características del Vecindario , Prostatectomía/estadística & datos numéricos , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/cirugía , Características de la Residencia/estadística & datos numéricos , Estrés Psicológico/genética , Blanco/genética , Blanco/estadística & datos numéricosRESUMEN
INTRODUCTION: Men with African ancestry have the highest incidence and mortality rates of prostate cancer (PCa) worldwide. METHODS: This study aimed to identify differentially methylated genes between tumor vs. adjacent normal and aggressive vs. indolent PCa in 121 African American patients. Epigenome-wide DNA methylation patterns in tumor DNA were assessed using the human Illumina Methylation EPIC V1 array. RESULTS: Around 5,139 differentially methylated CpG-sites (q < 0.01, lΔßl > 0.2) were identified when comparing normal vs. tumor, with an overall trend of hypermethylation in prostate tumors. Multiple representative differentially methylated regions (DMRs), including immune-related genes, such as CD40, Galectin3, OX40L, and STING, were detected in prostate tumors when compared to adjacent normal tissues. Based on an epigenetic clock model, we observed that tumors' total number of stem cell divisions and the stem cell division rate were significantly higher than adjacent normal tissues. Regarding PCa aggressiveness, 2,061 differentially methylated CpG-sites (q < 0.05, lΔßl > .05) were identified when the grade group (GG)1 was compared with GG4/5. Among these 2,061 CpG sites, 155 probes were consistently significant in more than one comparison. Among these genes, several immune system genes, such as COL18A1, S100A2, ITGA4, HLA-C, and ADCYAP1, have previously been linked to tumor progression in PCa. CONCLUSION: Several differentially methylated genes involved in immune-oncologic pathways associated with disease risk or aggressiveness were identified. In addition, 261 African American-specific differentially methylated genes related to the risk of PCa were identified. These results can shedlight on potential mechanisms contributing to PCa disparities in the African American Population.
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Negro o Afroamericano , Metilación de ADN , Estudio de Asociación del Genoma Completo , Neoplasias de la Próstata , Humanos , Masculino , Negro o Afroamericano/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/etnología , Persona de Mediana Edad , Anciano , Epigenoma , Islas de CpG , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Biomarcadores de Tumor/genéticaRESUMEN
Plant diversity effects on community productivity often increase over time. Whether the strengthening of diversity effects is caused by temporal shifts in species-level overyielding (i.e., higher species-level productivity in diverse communities compared with monocultures) remains unclear. Here, using data from 65 grassland and forest biodiversity experiments, we show that the temporal strength of diversity effects at the community scale is underpinned by temporal changes in the species that yield. These temporal trends of species-level overyielding are shaped by plant ecological strategies, which can be quantitatively delimited by functional traits. In grasslands, the temporal strengthening of biodiversity effects on community productivity was associated with increasing biomass overyielding of resource-conservative species increasing over time, and with overyielding of species characterized by fast resource acquisition either decreasing or increasing. In forests, temporal trends in species overyielding differ when considering above- versus belowground resource acquisition strategies. Overyielding in stem growth decreased for species with high light capture capacity but increased for those with high soil resource acquisition capacity. Our results imply that a diversity of species with different, and potentially complementary, ecological strategies is beneficial for maintaining community productivity over time in both grassland and forest ecosystems.
Asunto(s)
Biodiversidad , Ecosistema , Plantas , Biomasa , Bosques , PraderaRESUMEN
Because pesticides may operate through different mechanisms, the authors studied the risk of prostate cancer associated with specific pesticides in the Agricultural Health Study (1993-2007). With 1,962 incident cases, including 919 aggressive prostate cancers among 54,412 applicators, this is the largest study to date. Rate ratios and 95% confidence intervals were calculated by using Poisson regression to evaluate lifetime use of 48 pesticides and prostate cancer incidence. Three organophosphate insecticides were significantly associated with aggressive prostate cancer: fonofos (rate ratio (RR) for the highest quartile of exposure (Q4) vs. nonexposed = 1.63, 95% confidence interval (CI): 1.22, 2.17; P(trend) < 0.001); malathion (RR for Q4 vs. nonexposed = 1.43, 95% CI: 1.08, 1.88; P(trend) = 0.04); and terbufos (RR for Q4 vs. nonexposed = 1.29, 95% CI: 1.02, 1.64; P(trend) = 0.03). The organochlorine insecticide aldrin was also associated with increased risk of aggressive prostate cancer (RR for Q4 vs. nonexposed = 1.49, 95% CI: 1.03, 2.18; P(trend) = 0.02). This analysis has overcome several limitations of previous studies with the inclusion of a large number of cases with relevant exposure and detailed information on use of specific pesticides at 2 points in time. Furthermore, this is the first time specific pesticides are implicated as risk factors for aggressive prostate cancer.