The feasibility of SOMAscan, a multiplex, high sensitivity proteomics platform, for use in studies using archived plasma samples has not yet been assessed. We quantified 1,305 proteins from plasma samples donated by 16 Nurses’ Health Study (NHS) participants, 40 NHSII participants, and 12 local volunteers. We assessed assay reproducibility using coefficients of variation (CV) from duplicate samples and intra-class correlation coefficients (ICC) and Spearman correlation coefficients (r) of samples processed (i.e., centrifuged and aliquoted into separate components) immediately, 24, and 48 hours after collection, as well as those of samples collected from the same individuals 1 year apart. CVs were <20% for 99% of proteins overall and <10% for 92% of proteins in heparin samples compared to 66% for EDTA samples. We observed ICC or Spearman r (comparing immediate vs. 24-hour delayed processing) ≥0.75 for 61% of proteins, with some variation by anticoagulant (56% for heparin and 70% for EDTA) and protein class (ranging from 49% among kinases to 83% among hormones). Within-person stability over 1 year was good (ICC or Spearman r ≥ 0.4) for 91% of proteins. These results demonstrate the feasibility of SOMAscan for analyses of archived plasma samples.

While the association between exposure to secondhand smoke and lung cancer risk is well established, few studies with sufficient power have examined the association by histological type. In this study, we evaluated the secondhand smoke-lung cancer relationship by histological type based on pooled data from 18 case-control studies in the International Lung Cancer Consortium (ILCCO), including 2,504 cases and 7,276 controls who were never smokers and 10,184 cases and 7,176 controls who were ever smokers. We used multivariable logistic regression, adjusting for age, sex, race/ethnicity, smoking status, pack-years of smoking, and study. Among never smokers, the odds ratios (OR) comparing those ever exposed to secondhand smoke with those never exposed were 1.31 (95% CI: 1.17–1.45) for all histological types combined, 1.26 (95% CI: 1.10–1.44) for adenocarcinoma, 1.41 (95% CI: 0.99–1.99) for squamous cell carcinoma, 1.48 (95% CI: 0.89–2.45) for large cell lung cancer, and 3.09 (95% CI: 1.62–5.89) for small cell lung cancer. The estimated association with secondhand smoke exposure was greater for small cell lung cancer than for non-small cell lung cancers (OR=2.11, 95% CI: 1.11–4.04). This analysis is the largest to date investigating the relation between exposure to secondhand smoke and lung cancer. Our study provides more precise estimates of the impact of secondhand smoke on the major histological types of lung cancer, indicates the association with secondhand smoke is stronger for small cell lung cancer than for the other histological types, and suggests the importance of intervention against exposure to secondhand smoke in lung cancer prevention.

Objective: Cancer is a major public health burden both globally and in China. The most common cancer-related deaths in China are attributable to cancers of the lung, liver, stomach, and esophagus. Previous epidemiologic studies on cancer in China have often been limited by small sample sizes, inconsistent measurements, and lack of precise and accurate data. The Jiangsu Four Cancers (JFC) Study is a population-based case-control study conducted in an effort to obtain consistent and high quality data to investigate the life style, behavioral, environmental, and genetic factors associated with the four major cancers in China. The objective of this paper is to describe the overall design of the JFC Study and report selected findings on the major risk factors of cancers. Methods: Epidemiologic data were collected from 2003 to 2010 through in-person interviews using a structured questionnaire, and blood samples were drawn. Unconditional logistic regression was used to estimate the associations of putative risk factors with risks of cancers of the lung, liver, stomach, and esophagus. Results: The Study included 2,871 lung cancer cases, 2,018 liver cancer cases, 2,969 esophageal cancer cases, 2,216 stomach cancer cases, and 8,019 community controls. Low educational level, low income level, tobacco smoking, alcohol drinking, and family history of cancer were confirmed as risk factors of these major cancers. Conclusions: The JFC Study is one of the largest case-control studies of cancers in the Chinese population and will serve as a rich resource for future research on the four major cancers in China.