IL6 and breast cancer: We found stronger associations between BC and FVC among individuals with higher methylation at one of five CpG sites measured in F3. Similarly, we found stronger associations between CO and FVC among men with higher methylation at one of two CpG sites evaluated in IL6. IL6 encodes a protein that may act as both pro- and antiinflammatory cytokine and previous results in our cohort did not find any association of IL6 with lung function (Litonjua et al. 2003).