A dietary pattern associated with LINE-1 methylation alters the risk of developing cervical intraepithelial neoplasia

There is a paucity of research examining the relationships between dietary patterns and risk of developing precancerous lesions as well as biomarkers associated with such dietary patterns. The purpose of the current study was to identify dietary patterns that are associated with higher grades of cervical intraepithelial neoplasia (CIN 2+) and to determine whether these dietary patterns are associated with the degree of DNA methylation in the long interspersed nucleotide elements (L1s) of peripheral blood mononuclear cells (PBMCs), a biomarker associated with risk of developing CIN 2+. Study population consisted of 319 child-bearing age women. Dietary patterns were derived by factor analysis. The degree of PBMC L1 methylation was assessed by pyrosequencing. Logistic regression models were used to evaluate the associations between dietary patterns and CIN 2+. Similar models were used to evaluate the associations between dietary patterns and degree of PBMC L1 methylation in women free of CIN 2+. Women with the unhealthiest dietary pattern were 3.5 times more likely to be diagnosed with CIN 2+ than women with the healthiest dietary pattern [OR = 3.5; 95% confidence interval (CI), 1.2-10.1; P = 0.02]. Women at risk for developing CIN 2+ with the healthiest dietary pattern were 3.3 times more likely to have higher PBMC L1 methylation than women with the unhealthiest dietary pattern (OR = 3.3; 95% CI, 1.0-10.6; P = 0.04). Our findings suggest that human papilloma virus associated risk of developing CIN 2+ may be reduced by improving dietary patterns. The degree of PBMC L1 methylation may serve as a biomarker for monitoring the effectiveness of dietary modifications needed for reducing the risk of CIN 2+.