Assessment of polygenic architecture and risk prediction based on common variants across fourteen cancers.

Genome-wide association studies (GWAS) have led to the identification of hundreds of susceptibility loci across cancers, but the impact of further studies remains uncertain. Here we analyse summary-level data from GWAS of European ancestry across fourteen cancer sites to estimate the number of common susceptibility variants (polygenicity) and underlying effect-size distribution. All cancers show a high degree of polygenicity, involving at a minimum of thousands of loci. We project that sample sizes required to explain 80% of GWAS heritability vary from 60,000 cases for testicular to over 1,000,000 cases for lung cancer. The maximum relative risk achievable for subjects at the 99th risk percentile of underlying polygenic risk scores (PRS), compared to average risk, ranges from 12 for testicular to 2.5 for ovarian cancer. We show that PRS have potential for risk stratification for cancers of breast, colon and prostate, but less so for others because of modest heritability and lower incidence.

Dissecting racial disparities in multiple myeloma.

Multiple myeloma (MM) is a fatal plasma cell dyscrasia with a median overall survival of 5 to 10 years. MM progresses from the more common but often subclinical precursor states of monoclonal gammopathy of undetermined significance (MGUS), and smoldering multiple myeloma (SMM) to overt MM. There are large racial disparities in all stages of the disease. Compared with Whites, Blacks have an increased MGUS and MM risk and higher mortality rate, and have not experienced the same survival gains over time. The roots of this disparity are likely multifactorial in nature. Comparisons of Black and White MGUS and MM patients suggest that differences in risk factors, biology, and clinical characteristics exist by race or ancestry, which may explain some of the observed disparity in MM. However, poor accrual of Black MGUS and MM patients in clinical and epidemiological studies has limited our understanding of this disparity and hindered its elimination. Disparities in MM survival also exist but appear to stem from inferior treatment utilization and access rather than underlying pathogenesis. Innovative and multidisciplinary approaches are urgently needed to enhance our understanding of disparities that exist at each stage of the MM disease continuum and facilitate their elimination.

Serologic assessment of type 1 and type 2 immunity in healthy Japanese adults.

We assessed the informativeness of several serologic biomarkers of immune function using serum specimens collected in the Miyazaki Cohort Study from subjects who were seronegative for anti-human T-cell lymphotrophic virus I and anti-hepatitis C virus. To broadly characterize type 1 immune status, we measured EBV antibody titers, because titer profiles associated with cellular immune suppression are well described. We also tested for three type 2 biomarkers: total serum IgE, soluble CD23, and soluble CD30. Nonreactivity to a tuberculin purified protein derivative (PPD) skin test is indicative of diminished delayed-type hypersensitivity (type 1) responsiveness in the study population due to a history of tuberculosis exposure or Bacillus Calmette-Guérin vaccination. We therefore evaluated the serologic markers as predictors of PPD nonreactivity using logistic regression. Subjects whose EBV antibody profiles were consistent with deficient type 1 immunity were more than thrice as likely to be PPD nonreactive as persons with "normal" antibody titers. Elevated total IgE was also strongly associated with PPD nonreactivity (odds ratio 3.4, 95% confidence interval 1.2-9.9); elevated soluble CD23 had a weaker, but positive, odds ratio, whereas soluble CD30 levels were not predictive of PPD status. Therefore, PPD nonreactivity is associated, in this population, with a pattern of serum biomarkers that is indicative of diminished type 1 and elevated type 2 immunity. We conclude that, with the exception of soluble CD30, the serologic markers are informative for the characterization of type 1/type 2 immune status using archived sera from study populations of healthy adults.